/*
 * http://www.cascoda.com/products/ca-821x/
 * Copyright (c) 2016, Cascoda, Ltd.
 * All rights reserved.
 *
 * This code is dual-licensed under both GPLv2 and 3-clause BSD. What follows is
 * the license notice for both respectively.
 *
 *******************************************************************************
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 *******************************************************************************
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * 3. Neither the name of the copyright holder nor the names of its contributors
 * may be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <linux/cdev.h>
#include <linux/clk-provider.h>
#include <linux/debugfs.h>
#include <linux/delay.h>
#include <linux/gpio.h>
#include <linux/ieee802154.h>
#include <linux/io.h>
#include <linux/kfifo.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_gpio.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/poll.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/workqueue.h>
#include <linux/interrupt.h>

#include <net/ieee802154_netdev.h>
#include <net/mac802154.h>

#define DRIVER_NAME "ca8210"

/* external clock frequencies */
#define ONE_MHZ      1000000
#define TWO_MHZ      (2 * ONE_MHZ)
#define FOUR_MHZ     (4 * ONE_MHZ)
#define EIGHT_MHZ    (8 * ONE_MHZ)
#define SIXTEEN_MHZ  (16 * ONE_MHZ)

/* spi constants */
#define CA8210_SPI_BUF_SIZE 256
#define CA8210_SYNC_TIMEOUT 1000     /* Timeout for synchronous commands [ms] */

/* test interface constants */
#define CA8210_TEST_INT_FILE_NAME "ca8210_test"
#define CA8210_TEST_INT_FIFO_SIZE 256

/* HWME attribute IDs */
#define HWME_EDTHRESHOLD       (0x04)
#define HWME_EDVALUE           (0x06)
#define HWME_SYSCLKOUT         (0x0F)
#define HWME_LQILIMIT          (0x11)

/* TDME attribute IDs */
#define TDME_CHANNEL          (0x00)
#define TDME_ATM_CONFIG       (0x06)

#define MAX_HWME_ATTRIBUTE_SIZE  16
#define MAX_TDME_ATTRIBUTE_SIZE  2

/* PHY/MAC PIB Attribute Enumerations */
#define PHY_CURRENT_CHANNEL               (0x00)
#define PHY_TRANSMIT_POWER                (0x02)
#define PHY_CCA_MODE                      (0x03)
#define MAC_ASSOCIATION_PERMIT            (0x41)
#define MAC_AUTO_REQUEST                  (0x42)
#define MAC_BATT_LIFE_EXT                 (0x43)
#define MAC_BATT_LIFE_EXT_PERIODS         (0x44)
#define MAC_BEACON_PAYLOAD                (0x45)
#define MAC_BEACON_PAYLOAD_LENGTH         (0x46)
#define MAC_BEACON_ORDER                  (0x47)
#define MAC_GTS_PERMIT                    (0x4d)
#define MAC_MAX_CSMA_BACKOFFS             (0x4e)
#define MAC_MIN_BE                        (0x4f)
#define MAC_PAN_ID                        (0x50)
#define MAC_PROMISCUOUS_MODE              (0x51)
#define MAC_RX_ON_WHEN_IDLE               (0x52)
#define MAC_SHORT_ADDRESS                 (0x53)
#define MAC_SUPERFRAME_ORDER              (0x54)
#define MAC_ASSOCIATED_PAN_COORD          (0x56)
#define MAC_MAX_BE                        (0x57)
#define MAC_MAX_FRAME_RETRIES             (0x59)
#define MAC_RESPONSE_WAIT_TIME            (0x5A)
#define MAC_SECURITY_ENABLED              (0x5D)

#define MAC_AUTO_REQUEST_SECURITY_LEVEL   (0x78)
#define MAC_AUTO_REQUEST_KEY_ID_MODE      (0x79)

#define NS_IEEE_ADDRESS                   (0xFF) /* Non-standard IEEE address */

/* MAC Address Mode Definitions */
#define MAC_MODE_NO_ADDR                (0x00)
#define MAC_MODE_SHORT_ADDR             (0x02)
#define MAC_MODE_LONG_ADDR              (0x03)

/* MAC constants */
#define MAX_BEACON_OVERHEAD        (75)
#define MAX_BEACON_PAYLOAD_LENGTH  (IEEE802154_MTU - MAX_BEACON_OVERHEAD)

#define MAX_ATTRIBUTE_SIZE              (122)
#define MAX_DATA_SIZE                   (114)

#define CA8210_VALID_CHANNELS                 (0x07FFF800)

/* MAC workarounds for V1.1 and MPW silicon (V0.x) */
#define CA8210_MAC_WORKAROUNDS (0)
#define CA8210_MAC_MPW         (0)

/* memory manipulation macros */
#define LS_BYTE(x)     ((u8)((x) & 0xFF))
#define MS_BYTE(x)     ((u8)(((x) >> 8) & 0xFF))

/* message ID codes in SPI commands */
/* downstream */
#define MCPS_DATA_REQUEST                     (0x00)
#define MLME_ASSOCIATE_REQUEST                (0x02)
#define MLME_ASSOCIATE_RESPONSE               (0x03)
#define MLME_DISASSOCIATE_REQUEST             (0x04)
#define MLME_GET_REQUEST                      (0x05)
#define MLME_ORPHAN_RESPONSE                  (0x06)
#define MLME_RESET_REQUEST                    (0x07)
#define MLME_RX_ENABLE_REQUEST                (0x08)
#define MLME_SCAN_REQUEST                     (0x09)
#define MLME_SET_REQUEST                      (0x0A)
#define MLME_START_REQUEST                    (0x0B)
#define MLME_POLL_REQUEST                     (0x0D)
#define HWME_SET_REQUEST                      (0x0E)
#define HWME_GET_REQUEST                      (0x0F)
#define TDME_SETSFR_REQUEST                   (0x11)
#define TDME_GETSFR_REQUEST                   (0x12)
#define TDME_SET_REQUEST                      (0x14)
/* upstream */
#define MCPS_DATA_INDICATION                  (0x00)
#define MCPS_DATA_CONFIRM                     (0x01)
#define MLME_RESET_CONFIRM                    (0x0A)
#define MLME_SET_CONFIRM                      (0x0E)
#define MLME_START_CONFIRM                    (0x0F)
#define HWME_SET_CONFIRM                      (0x12)
#define HWME_GET_CONFIRM                      (0x13)
#define HWME_WAKEUP_INDICATION		      (0x15)
#define TDME_SETSFR_CONFIRM                   (0x17)

/* SPI command IDs */
/* bit indicating a confirm or indication from slave to master */
#define SPI_S2M                            (0x20)
/* bit indicating a synchronous message */
#define SPI_SYN                            (0x40)

/* SPI command definitions */
#define SPI_IDLE                           (0xFF)
#define SPI_NACK                           (0xF0)

#define SPI_MCPS_DATA_REQUEST          (MCPS_DATA_REQUEST)
#define SPI_MCPS_DATA_INDICATION       (MCPS_DATA_INDICATION + SPI_S2M)
#define SPI_MCPS_DATA_CONFIRM          (MCPS_DATA_CONFIRM + SPI_S2M)

#define SPI_MLME_ASSOCIATE_REQUEST     (MLME_ASSOCIATE_REQUEST)
#define SPI_MLME_RESET_REQUEST         (MLME_RESET_REQUEST + SPI_SYN)
#define SPI_MLME_SET_REQUEST           (MLME_SET_REQUEST + SPI_SYN)
#define SPI_MLME_START_REQUEST         (MLME_START_REQUEST + SPI_SYN)
#define SPI_MLME_RESET_CONFIRM         (MLME_RESET_CONFIRM + SPI_S2M + SPI_SYN)
#define SPI_MLME_SET_CONFIRM           (MLME_SET_CONFIRM + SPI_S2M + SPI_SYN)
#define SPI_MLME_START_CONFIRM         (MLME_START_CONFIRM + SPI_S2M + SPI_SYN)

#define SPI_HWME_SET_REQUEST           (HWME_SET_REQUEST + SPI_SYN)
#define SPI_HWME_GET_REQUEST           (HWME_GET_REQUEST + SPI_SYN)
#define SPI_HWME_SET_CONFIRM           (HWME_SET_CONFIRM + SPI_S2M + SPI_SYN)
#define SPI_HWME_GET_CONFIRM           (HWME_GET_CONFIRM + SPI_S2M + SPI_SYN)
#define SPI_HWME_WAKEUP_INDICATION     (HWME_WAKEUP_INDICATION + SPI_S2M)

#define SPI_TDME_SETSFR_REQUEST        (TDME_SETSFR_REQUEST + SPI_SYN)
#define SPI_TDME_SET_REQUEST           (TDME_SET_REQUEST + SPI_SYN)
#define SPI_TDME_SETSFR_CONFIRM        (TDME_SETSFR_CONFIRM + SPI_S2M + SPI_SYN)

/* TDME SFR addresses */
/* Page 0 */
#define CA8210_SFR_PACFG                   (0xB1)
#define CA8210_SFR_MACCON                  (0xD8)
#define CA8210_SFR_PACFGIB                 (0xFE)
/* Page 1 */
#define CA8210_SFR_LOTXCAL                 (0xBF)
#define CA8210_SFR_PTHRH                   (0xD1)
#define CA8210_SFR_PRECFG                  (0xD3)
#define CA8210_SFR_LNAGX40                 (0xE1)
#define CA8210_SFR_LNAGX41                 (0xE2)
#define CA8210_SFR_LNAGX42                 (0xE3)
#define CA8210_SFR_LNAGX43                 (0xE4)
#define CA8210_SFR_LNAGX44                 (0xE5)
#define CA8210_SFR_LNAGX45                 (0xE6)
#define CA8210_SFR_LNAGX46                 (0xE7)
#define CA8210_SFR_LNAGX47                 (0xE9)

#define PACFGIB_DEFAULT_CURRENT            (0x3F)
#define PTHRH_DEFAULT_THRESHOLD            (0x5A)
#define LNAGX40_DEFAULT_GAIN               (0x29) /* 10dB */
#define LNAGX41_DEFAULT_GAIN               (0x54) /* 21dB */
#define LNAGX42_DEFAULT_GAIN               (0x6C) /* 27dB */
#define LNAGX43_DEFAULT_GAIN               (0x7A) /* 30dB */
#define LNAGX44_DEFAULT_GAIN               (0x84) /* 33dB */
#define LNAGX45_DEFAULT_GAIN               (0x8B) /* 34dB */
#define LNAGX46_DEFAULT_GAIN               (0x92) /* 36dB */
#define LNAGX47_DEFAULT_GAIN               (0x96) /* 37dB */

#define CA8210_IOCTL_HARD_RESET            (0x00)

/* Structs/Enums */

/**
 * struct cas_control - spi transfer structure
 * @msg:                  spi_message for each exchange
 * @transfer:             spi_transfer for each exchange
 * @tx_buf:               source array for transmission
 * @tx_in_buf:            array storing bytes received during transmission
 * @priv:                 pointer to private data
 *
 * This structure stores all the necessary data passed around during a single
 * spi exchange.
 */
struct cas_control {
	struct spi_message msg;
	struct spi_transfer transfer;

	u8 tx_buf[CA8210_SPI_BUF_SIZE];
	u8 tx_in_buf[CA8210_SPI_BUF_SIZE];

	struct ca8210_priv *priv;
};

/**
 * struct ca8210_test - ca8210 test interface structure
 * @ca8210_dfs_spi_int: pointer to the entry in the debug fs for this device
 * @up_fifo:            fifo for upstream messages
 * @readq:              read wait queue
 *
 * This structure stores all the data pertaining to the debug interface
 */
struct ca8210_test {
	struct dentry *ca8210_dfs_spi_int;
	struct kfifo up_fifo;
	wait_queue_head_t readq;
};

/**
 * struct ca8210_priv - ca8210 private data structure
 * @spi:                    pointer to the ca8210 spi device object
 * @hw:                     pointer to the ca8210 ieee802154_hw object
 * @hw_registered:          true if hw has been registered with ieee802154
 * @lock:                   spinlock protecting the private data area
 * @mlme_workqueue:           workqueue for triggering MLME Reset
 * @irq_workqueue:          workqueue for irq processing
 * @tx_skb:                 current socket buffer to transmit
 * @nextmsduhandle:         msdu handle to pass to the 15.4 MAC layer for the
 *                           next transmission
 * @clk:                    external clock provided by the ca8210
 * @last_dsn:               sequence number of last data packet received, for
 *                           resend detection
 * @test:                   test interface data section for this instance
 * @async_tx_pending:       true if an asynchronous transmission was started and
 *                           is not complete
 * @sync_command_response:  pointer to buffer to fill with sync response
 * @ca8210_is_awake:        nonzero if ca8210 is initialised, ready for comms
 * @sync_down:              counts number of downstream synchronous commands
 * @sync_up:                counts number of upstream synchronous commands
 * @spi_transfer_complete:  completion object for a single spi_transfer
 * @sync_exchange_complete: completion object for a complete synchronous API
 *                          exchange
 * @promiscuous:            whether the ca8210 is in promiscuous mode or not
 * @retries:                records how many times the current pending spi
 *                          transfer has been retried
 */
struct ca8210_priv {
	struct spi_device *spi;
	struct ieee802154_hw *hw;
	bool hw_registered;
	spinlock_t lock;
	struct workqueue_struct *mlme_workqueue;
	struct workqueue_struct *irq_workqueue;
	struct sk_buff *tx_skb;
	u8 nextmsduhandle;
	struct clk *clk;
	int last_dsn;
	struct ca8210_test test;
	bool async_tx_pending;
	u8 *sync_command_response;
	struct completion ca8210_is_awake;
	int sync_down, sync_up;
	struct completion spi_transfer_complete, sync_exchange_complete;
	bool promiscuous;
	int retries;
};

/**
 * struct work_priv_container - link between a work object and the relevant
 *                              device's private data
 * @work: work object being executed
 * @priv: device's private data section
 *
 */
struct work_priv_container {
	struct work_struct work;
	struct ca8210_priv *priv;
};

/**
 * struct ca8210_platform_data - ca8210 platform data structure
 * @extclockenable: true if the external clock is to be enabled
 * @extclockfreq:   frequency of the external clock
 * @extclockgpio:   ca8210 output gpio of the external clock
 * @gpio_reset:     gpio number of ca8210 reset line
 * @gpio_irq:       gpio number of ca8210 interrupt line
 * @irq_id:         identifier for the ca8210 irq
 *
 */
struct ca8210_platform_data {
	bool extclockenable;
	unsigned int extclockfreq;
	unsigned int extclockgpio;
	int gpio_reset;
	int gpio_irq;
	int irq_id;
};

/**
 * struct fulladdr - full MAC addressing information structure
 * @mode:    address mode (none, short, extended)
 * @pan_id:  16-bit LE pan id
 * @address: LE address, variable length as specified by mode
 *
 */
struct fulladdr {
	u8         mode;
	u8         pan_id[2];
	u8         address[8];
};

/**
 * union macaddr: generic MAC address container
 * @short_address: 16-bit short address
 * @ieee_address:  64-bit extended address as LE byte array
 *
 */
union macaddr {
	u16        short_address;
	u8         ieee_address[8];
};

/**
 * struct secspec: security specification for SAP commands
 * @security_level: 0-7, controls level of authentication & encryption
 * @key_id_mode:    0-3, specifies how to obtain key
 * @key_source:     extended key retrieval data
 * @key_index:      single-byte key identifier
 *
 */
struct secspec {
	u8         security_level;
	u8         key_id_mode;
	u8         key_source[8];
	u8         key_index;
};

/* downlink functions parameter set definitions */
struct mcps_data_request_pset {
	u8              src_addr_mode;
	struct fulladdr dst;
	u8              msdu_length;
	u8              msdu_handle;
	u8              tx_options;
	u8              msdu[MAX_DATA_SIZE];
};

struct mlme_set_request_pset {
	u8         pib_attribute;
	u8         pib_attribute_index;
	u8         pib_attribute_length;
	u8         pib_attribute_value[MAX_ATTRIBUTE_SIZE];
};

struct hwme_set_request_pset {
	u8         hw_attribute;
	u8         hw_attribute_length;
	u8         hw_attribute_value[MAX_HWME_ATTRIBUTE_SIZE];
};

struct hwme_get_request_pset {
	u8         hw_attribute;
};

struct tdme_setsfr_request_pset {
	u8         sfr_page;
	u8         sfr_address;
	u8         sfr_value;
};

/* uplink functions parameter set definitions */
struct hwme_set_confirm_pset {
	u8         status;
	u8         hw_attribute;
};

struct hwme_get_confirm_pset {
	u8         status;
	u8         hw_attribute;
	u8         hw_attribute_length;
	u8         hw_attribute_value[MAX_HWME_ATTRIBUTE_SIZE];
};

struct tdme_setsfr_confirm_pset {
	u8         status;
	u8         sfr_page;
	u8         sfr_address;
};

struct mac_message {
	u8      command_id;
	u8      length;
	union {
		struct mcps_data_request_pset       data_req;
		struct mlme_set_request_pset        set_req;
		struct hwme_set_request_pset        hwme_set_req;
		struct hwme_get_request_pset        hwme_get_req;
		struct tdme_setsfr_request_pset     tdme_set_sfr_req;
		struct hwme_set_confirm_pset        hwme_set_cnf;
		struct hwme_get_confirm_pset        hwme_get_cnf;
		struct tdme_setsfr_confirm_pset     tdme_set_sfr_cnf;
		u8                                  u8param;
		u8                                  status;
		u8                                  payload[148];
	} pdata;
};

union pa_cfg_sfr {
	struct {
		u8 bias_current_trim     : 3;
		u8 /* reserved */        : 1;
		u8 buffer_capacitor_trim : 3;
		u8 boost                 : 1;
	};
	u8 paib;
};

struct preamble_cfg_sfr {
	u8 timeout_symbols      : 3;
	u8 acquisition_symbols  : 3;
	u8 search_symbols       : 2;
};

static int (*cascoda_api_upstream)(
	const u8 *buf,
	size_t len,
	void *device_ref
);

/**
 * link_to_linux_err() - Translates an 802.15.4 return code into the closest
 *                       linux error
 * @link_status:  802.15.4 status code
 *
 * Return: 0 or Linux error code
 */
static int link_to_linux_err(int link_status)
{
	if (link_status < 0) {
		/* status is already a Linux code */
		return link_status;
	}
	switch (link_status) {
	case IEEE802154_SUCCESS:
	case IEEE802154_REALIGNMENT:
		return 0;
	case IEEE802154_IMPROPER_KEY_TYPE:
		return -EKEYREJECTED;
	case IEEE802154_IMPROPER_SECURITY_LEVEL:
	case IEEE802154_UNSUPPORTED_LEGACY:
	case IEEE802154_DENIED:
		return -EACCES;
	case IEEE802154_BEACON_LOST:
	case IEEE802154_NO_ACK:
	case IEEE802154_NO_BEACON:
		return -ENETUNREACH;
	case IEEE802154_CHANNEL_ACCESS_FAILURE:
	case IEEE802154_TX_ACTIVE:
	case IEEE802154_SCAN_IN_PROGRESS:
		return -EBUSY;
	case IEEE802154_DISABLE_TRX_FAILURE:
	case IEEE802154_OUT_OF_CAP:
		return -EAGAIN;
	case IEEE802154_FRAME_TOO_LONG:
		return -EMSGSIZE;
	case IEEE802154_INVALID_GTS:
	case IEEE802154_PAST_TIME:
		return -EBADSLT;
	case IEEE802154_INVALID_HANDLE:
		return -EBADMSG;
	case IEEE802154_INVALID_PARAMETER:
	case IEEE802154_UNSUPPORTED_ATTRIBUTE:
	case IEEE802154_ON_TIME_TOO_LONG:
	case IEEE802154_INVALID_INDEX:
		return -EINVAL;
	case IEEE802154_NO_DATA:
		return -ENODATA;
	case IEEE802154_NO_SHORT_ADDRESS:
		return -EFAULT;
	case IEEE802154_PAN_ID_CONFLICT:
		return -EADDRINUSE;
	case IEEE802154_TRANSACTION_EXPIRED:
		return -ETIME;
	case IEEE802154_TRANSACTION_OVERFLOW:
		return -ENOBUFS;
	case IEEE802154_UNAVAILABLE_KEY:
		return -ENOKEY;
	case IEEE802154_INVALID_ADDRESS:
		return -ENXIO;
	case IEEE802154_TRACKING_OFF:
	case IEEE802154_SUPERFRAME_OVERLAP:
		return -EREMOTEIO;
	case IEEE802154_LIMIT_REACHED:
		return -EDQUOT;
	case IEEE802154_READ_ONLY:
		return -EROFS;
	default:
		return -EPROTO;
	}
}

/**
 * ca8210_test_int_driver_write() - Writes a message to the test interface to be
 *                                  read by the userspace
 * @buf:  Buffer containing upstream message
 * @len:  length of message to write
 * @spi:  SPI device of message originator
 *
 * Return: 0 or linux error code
 */
static int ca8210_test_int_driver_write(
	const u8       *buf,
	size_t          len,
	void           *spi
)
{
	struct ca8210_priv *priv = spi_get_drvdata(spi);
	struct ca8210_test *test = &priv->test;
	char *fifo_buffer;
	int i;

	dev_dbg(
		&priv->spi->dev,
		"test_interface: Buffering upstream message:\n"
	);
	for (i = 0; i < len; i++)
		dev_dbg(&priv->spi->dev, "%#03x\n", buf[i]);

	fifo_buffer = kmemdup(buf, len, GFP_KERNEL);
	if (!fifo_buffer)
		return -ENOMEM;
	kfifo_in(&test->up_fifo, &fifo_buffer, 4);
	wake_up_interruptible(&priv->test.readq);

	return 0;
}

/* SPI Operation */

static int ca8210_net_rx(
	struct ieee802154_hw  *hw,
	u8                    *command,
	size_t                 len
);
static u8 mlme_reset_request_sync(
	u8       set_default_pib,
	void    *device_ref
);
static int ca8210_spi_transfer(
	struct spi_device *spi,
	const u8          *buf,
	size_t             len
);

/**
 * ca8210_reset_send() - Hard resets the ca8210 for a given time
 * @spi:  Pointer to target ca8210 spi device
 * @ms:   Milliseconds to hold the reset line low for
 */
static void ca8210_reset_send(struct spi_device *spi, unsigned int ms)
{
	struct ca8210_platform_data *pdata = spi->dev.platform_data;
	struct ca8210_priv *priv = spi_get_drvdata(spi);
	long status;

	gpio_set_value(pdata->gpio_reset, 0);
	reinit_completion(&priv->ca8210_is_awake);
	msleep(ms);
	gpio_set_value(pdata->gpio_reset, 1);
	priv->promiscuous = false;

	/* Wait until wakeup indication seen */
	status = wait_for_completion_interruptible_timeout(
		&priv->ca8210_is_awake,
		msecs_to_jiffies(CA8210_SYNC_TIMEOUT)
	);
	if (status == 0) {
		dev_crit(
			&spi->dev,
			"Fatal: No wakeup from ca8210 after reset!\n"
		);
	}

	dev_dbg(&spi->dev, "Reset the device\n");
}

/**
 * ca8210_mlme_reset_worker() - Resets the MLME, Called when the MAC OVERFLOW
 *                              condition happens.
 * @work:  Pointer to work being executed
 */
static void ca8210_mlme_reset_worker(struct work_struct *work)
{
	struct work_priv_container *wpc = container_of(
		work,
		struct work_priv_container,
		work
	);
	struct ca8210_priv *priv = wpc->priv;

	mlme_reset_request_sync(0, priv->spi);
	kfree(wpc);
}

/**
 * ca8210_rx_done() - Calls various message dispatches responding to a received
 *                    command
 * @cas_ctl: Pointer to the cas_control object for the relevant spi transfer
 *
 * Presents a received SAP command from the ca8210 to the Cascoda EVBME, test
 * interface and network driver.
 */
static void ca8210_rx_done(struct cas_control *cas_ctl)
{
	u8 *buf;
	unsigned int len;
	struct work_priv_container *mlme_reset_wpc;
	struct ca8210_priv *priv = cas_ctl->priv;

	buf = cas_ctl->tx_in_buf;
	len = buf[1] + 2;
	if (len > CA8210_SPI_BUF_SIZE) {
		dev_crit(
			&priv->spi->dev,
			"Received packet len (%u) erroneously long\n",
			len
		);
		goto finish;
	}

	if (buf[0] & SPI_SYN) {
		if (priv->sync_command_response) {
			memcpy(priv->sync_command_response, buf, len);
			complete(&priv->sync_exchange_complete);
		} else {
			if (cascoda_api_upstream)
				cascoda_api_upstream(buf, len, priv->spi);
			priv->sync_up++;
		}
	} else {
		if (cascoda_api_upstream)
			cascoda_api_upstream(buf, len, priv->spi);
	}

	ca8210_net_rx(priv->hw, buf, len);
	if (buf[0] == SPI_MCPS_DATA_CONFIRM) {
		if (buf[3] == IEEE802154_TRANSACTION_OVERFLOW) {
			dev_info(
				&priv->spi->dev,
				"Waiting for transaction overflow to stabilise...\n");
			msleep(2000);
			dev_info(
				&priv->spi->dev,
				"Resetting MAC...\n");

			mlme_reset_wpc = kmalloc(sizeof(*mlme_reset_wpc),
						 GFP_KERNEL);
			if (!mlme_reset_wpc)
				goto finish;
			INIT_WORK(
				&mlme_reset_wpc->work,
				ca8210_mlme_reset_worker
			);
			mlme_reset_wpc->priv = priv;
			queue_work(priv->mlme_workqueue, &mlme_reset_wpc->work);
		}
	} else if (buf[0] == SPI_HWME_WAKEUP_INDICATION) {
		dev_notice(
			&priv->spi->dev,
			"Wakeup indication received, reason:\n"
		);
		switch (buf[2]) {
		case 0:
			dev_notice(
				&priv->spi->dev,
				"Transceiver woken up from Power Up / System Reset\n"
			);
			break;
		case 1:
			dev_notice(
				&priv->spi->dev,
				"Watchdog Timer Time-Out\n"
			);
			break;
		case 2:
			dev_notice(
				&priv->spi->dev,
				"Transceiver woken up from Power-Off by Sleep Timer Time-Out\n");
			break;
		case 3:
			dev_notice(
				&priv->spi->dev,
				"Transceiver woken up from Power-Off by GPIO Activity\n"
			);
			break;
		case 4:
			dev_notice(
				&priv->spi->dev,
				"Transceiver woken up from Standby by Sleep Timer Time-Out\n"
			);
			break;
		case 5:
			dev_notice(
				&priv->spi->dev,
				"Transceiver woken up from Standby by GPIO Activity\n"
			);
			break;
		case 6:
			dev_notice(
				&priv->spi->dev,
				"Sleep-Timer Time-Out in Active Mode\n"
			);
			break;
		default:
			dev_warn(&priv->spi->dev, "Wakeup reason unknown\n");
			break;
		}
		complete(&priv->ca8210_is_awake);
	}

finish:;
}

static void ca8210_remove(struct spi_device *spi_device);

/**
 * ca8210_spi_transfer_complete() - Called when a single spi transfer has
 *                                  completed
 * @context:  Pointer to the cas_control object for the finished transfer
 */
static void ca8210_spi_transfer_complete(void *context)
{
	struct cas_control *cas_ctl = context;
	struct ca8210_priv *priv = cas_ctl->priv;
	bool duplex_rx = false;
	int i;
	u8 retry_buffer[CA8210_SPI_BUF_SIZE];

	if (
		cas_ctl->tx_in_buf[0] == SPI_NACK ||
		(cas_ctl->tx_in_buf[0] == SPI_IDLE &&
		cas_ctl->tx_in_buf[1] == SPI_NACK)
	) {
		/* ca8210 is busy */
		dev_info(&priv->spi->dev, "ca8210 was busy during attempted write\n");
		if (cas_ctl->tx_buf[0] == SPI_IDLE) {
			dev_warn(
				&priv->spi->dev,
				"IRQ servicing NACKd, dropping transfer\n"
			);
			kfree(cas_ctl);
			return;
		}
		if (priv->retries > 3) {
			dev_err(&priv->spi->dev, "too many retries!\n");
			kfree(cas_ctl);
			ca8210_remove(priv->spi);
			return;
		}
		memcpy(retry_buffer, cas_ctl->tx_buf, CA8210_SPI_BUF_SIZE);
		kfree(cas_ctl);
		ca8210_spi_transfer(
			priv->spi,
			retry_buffer,
			CA8210_SPI_BUF_SIZE
		);
		priv->retries++;
		dev_info(&priv->spi->dev, "retried spi write\n");
		return;
	} else if (
			cas_ctl->tx_in_buf[0] != SPI_IDLE &&
			cas_ctl->tx_in_buf[0] != SPI_NACK
		) {
		duplex_rx = true;
	}

	if (duplex_rx) {
		dev_dbg(&priv->spi->dev, "READ CMD DURING TX\n");
		for (i = 0; i < cas_ctl->tx_in_buf[1] + 2; i++)
			dev_dbg(
				&priv->spi->dev,
				"%#03x\n",
				cas_ctl->tx_in_buf[i]
			);
		ca8210_rx_done(cas_ctl);
	}
	complete(&priv->spi_transfer_complete);
	kfree(cas_ctl);
	priv->retries = 0;
}

/**
 * ca8210_spi_transfer() - Initiate duplex spi transfer with ca8210
 * @spi: Pointer to spi device for transfer
 * @buf: Octet array to send
 * @len: length of the buffer being sent
 *
 * Return: 0 or linux error code
 */
static int ca8210_spi_transfer(
	struct spi_device  *spi,
	const u8           *buf,
	size_t              len
)
{
	int i, status = 0;
	struct ca8210_priv *priv;
	struct cas_control *cas_ctl;

	if (!spi) {
		pr_crit("NULL spi device passed to %s\n", __func__);
		return -ENODEV;
	}

	priv = spi_get_drvdata(spi);
	reinit_completion(&priv->spi_transfer_complete);

	dev_dbg(&spi->dev, "%s called\n", __func__);

	cas_ctl = kzalloc(sizeof(*cas_ctl), GFP_ATOMIC);
	if (!cas_ctl)
		return -ENOMEM;

	cas_ctl->priv = priv;
	memset(cas_ctl->tx_buf, SPI_IDLE, CA8210_SPI_BUF_SIZE);
	memset(cas_ctl->tx_in_buf, SPI_IDLE, CA8210_SPI_BUF_SIZE);
	memcpy(cas_ctl->tx_buf, buf, len);

	for (i = 0; i < len; i++)
		dev_dbg(&spi->dev, "%#03x\n", cas_ctl->tx_buf[i]);

	spi_message_init(&cas_ctl->msg);

	cas_ctl->transfer.tx_nbits = 1; /* 1 MOSI line */
	cas_ctl->transfer.rx_nbits = 1; /* 1 MISO line */
	cas_ctl->transfer.speed_hz = 0; /* Use device setting */
	cas_ctl->transfer.bits_per_word = 0; /* Use device setting */
	cas_ctl->transfer.tx_buf = cas_ctl->tx_buf;
	cas_ctl->transfer.rx_buf = cas_ctl->tx_in_buf;
	cas_ctl->transfer.delay.value = 0;
	cas_ctl->transfer.delay.unit = SPI_DELAY_UNIT_USECS;
	cas_ctl->transfer.cs_change = 0;
	cas_ctl->transfer.len = sizeof(struct mac_message);
	cas_ctl->msg.complete = ca8210_spi_transfer_complete;
	cas_ctl->msg.context = cas_ctl;

	spi_message_add_tail(
		&cas_ctl->transfer,
		&cas_ctl->msg
	);

	status = spi_async(spi, &cas_ctl->msg);
	if (status < 0) {
		dev_crit(
			&spi->dev,
			"status %d from spi_sync in write\n",
			status
		);
	}

	return status;
}

/**
 * ca8210_spi_exchange() - Exchange API/SAP commands with the radio
 * @buf:         Octet array of command being sent downstream
 * @len:         length of buf
 * @response:    buffer for storing synchronous response
 * @device_ref:  spi_device pointer for ca8210
 *
 * Effectively calls ca8210_spi_transfer to write buf[] to the spi, then for
 * synchronous commands waits for the corresponding response to be read from
 * the spi before returning. The response is written to the response parameter.
 *
 * Return: 0 or linux error code
 */
static int ca8210_spi_exchange(
	const u8 *buf,
	size_t len,
	u8 *response,
	void *device_ref
)
{
	int status = 0;
	struct spi_device *spi = device_ref;
	struct ca8210_priv *priv = spi->dev.driver_data;
	long wait_remaining;

	if ((buf[0] & SPI_SYN) && response) { /* if sync wait for confirm */
		reinit_completion(&priv->sync_exchange_complete);
		priv->sync_command_response = response;
	}

	do {
		reinit_completion(&priv->spi_transfer_complete);
		status = ca8210_spi_transfer(priv->spi, buf, len);
		if (status) {
			dev_warn(
				&spi->dev,
				"spi write failed, returned %d\n",
				status
			);
			if (status == -EBUSY)
				continue;
			if (((buf[0] & SPI_SYN) && response))
				complete(&priv->sync_exchange_complete);
			goto cleanup;
		}

		wait_remaining = wait_for_completion_interruptible_timeout(
			&priv->spi_transfer_complete,
			msecs_to_jiffies(1000)
		);
		if (wait_remaining == -ERESTARTSYS) {
			status = -ERESTARTSYS;
		} else if (wait_remaining == 0) {
			dev_err(
				&spi->dev,
				"SPI downstream transfer timed out!\n"
			);
			status = -ETIME;
			goto cleanup;
		}
	} while (status < 0);

	if (!((buf[0] & SPI_SYN) && response))
		goto cleanup;

	wait_remaining = wait_for_completion_interruptible_timeout(
		&priv->sync_exchange_complete,
		msecs_to_jiffies(CA8210_SYNC_TIMEOUT)
	);
	if (wait_remaining == -ERESTARTSYS) {
		status = -ERESTARTSYS;
	} else if (wait_remaining == 0) {
		dev_err(
			&spi->dev,
			"Synchronous confirm timeout\n"
		);
		status = -ETIME;
	}

cleanup:
	priv->sync_command_response = NULL;
	return status;
}

/**
 * ca8210_interrupt_handler() - Called when an irq is received from the ca8210
 * @irq:     Id of the irq being handled
 * @dev_id:  Pointer passed by the system, pointing to the ca8210's private data
 *
 * This function is called when the irq line from the ca8210 is asserted,
 * signifying that the ca8210 has a message to send upstream to us. Starts the
 * asynchronous spi read.
 *
 * Return: irq return code
 */
static irqreturn_t ca8210_interrupt_handler(int irq, void *dev_id)
{
	struct ca8210_priv *priv = dev_id;
	int status;

	dev_dbg(&priv->spi->dev, "irq: Interrupt occurred\n");
	do {
		status = ca8210_spi_transfer(priv->spi, NULL, 0);
		if (status && (status != -EBUSY)) {
			dev_warn(
				&priv->spi->dev,
				"spi read failed, returned %d\n",
				status
			);
		}
	} while (status == -EBUSY);
	return IRQ_HANDLED;
}

static int (*cascoda_api_downstream)(
	const u8 *buf,
	size_t len,
	u8 *response,
	void *device_ref
) = ca8210_spi_exchange;

/* Cascoda API / 15.4 SAP Primitives */

/**
 * tdme_setsfr_request_sync() - TDME_SETSFR_request/confirm according to API
 * @sfr_page:    SFR Page
 * @sfr_address: SFR Address
 * @sfr_value:   SFR Value
 * @device_ref:  Nondescript pointer to target device
 *
 * Return: 802.15.4 status code of TDME-SETSFR.confirm
 */
static u8 tdme_setsfr_request_sync(
	u8            sfr_page,
	u8            sfr_address,
	u8            sfr_value,
	void         *device_ref
)
{
	int ret;
	struct mac_message command, response;
	struct spi_device *spi = device_ref;

	command.command_id = SPI_TDME_SETSFR_REQUEST;
	command.length = 3;
	command.pdata.tdme_set_sfr_req.sfr_page    = sfr_page;
	command.pdata.tdme_set_sfr_req.sfr_address = sfr_address;
	command.pdata.tdme_set_sfr_req.sfr_value   = sfr_value;
	response.command_id = SPI_IDLE;
	ret = cascoda_api_downstream(
		&command.command_id,
		command.length + 2,
		&response.command_id,
		device_ref
	);
	if (ret) {
		dev_crit(&spi->dev, "cascoda_api_downstream returned %d", ret);
		return IEEE802154_SYSTEM_ERROR;
	}

	if (response.command_id != SPI_TDME_SETSFR_CONFIRM) {
		dev_crit(
			&spi->dev,
			"sync response to SPI_TDME_SETSFR_REQUEST was not SPI_TDME_SETSFR_CONFIRM, it was %d\n",
			response.command_id
		);
		return IEEE802154_SYSTEM_ERROR;
	}

	return response.pdata.tdme_set_sfr_cnf.status;
}

/**
 * tdme_chipinit() - TDME Chip Register Default Initialisation Macro
 * @device_ref: Nondescript pointer to target device
 *
 * Return: 802.15.4 status code of API calls
 */
static u8 tdme_chipinit(void *device_ref)
{
	u8 status = IEEE802154_SUCCESS;
	u8 sfr_address;
	struct spi_device *spi = device_ref;
	struct preamble_cfg_sfr pre_cfg_value = {
		.timeout_symbols     = 3,
		.acquisition_symbols = 3,
		.search_symbols      = 1,
	};
	/* LNA Gain Settings */
	status = tdme_setsfr_request_sync(
		1, (sfr_address = CA8210_SFR_LNAGX40),
		LNAGX40_DEFAULT_GAIN, device_ref);
	if (status)
		goto finish;
	status = tdme_setsfr_request_sync(
		1, (sfr_address = CA8210_SFR_LNAGX41),
		LNAGX41_DEFAULT_GAIN, device_ref);
	if (status)
		goto finish;
	status = tdme_setsfr_request_sync(
		1, (sfr_address = CA8210_SFR_LNAGX42),
		LNAGX42_DEFAULT_GAIN, device_ref);
	if (status)
		goto finish;
	status = tdme_setsfr_request_sync(
		1, (sfr_address = CA8210_SFR_LNAGX43),
		LNAGX43_DEFAULT_GAIN, device_ref);
	if (status)
		goto finish;
	status = tdme_setsfr_request_sync(
		1, (sfr_address = CA8210_SFR_LNAGX44),
		LNAGX44_DEFAULT_GAIN, device_ref);
	if (status)
		goto finish;
	status = tdme_setsfr_request_sync(
		1, (sfr_address = CA8210_SFR_LNAGX45),
		LNAGX45_DEFAULT_GAIN, device_ref);
	if (status)
		goto finish;
	status = tdme_setsfr_request_sync(
		1, (sfr_address = CA8210_SFR_LNAGX46),
		LNAGX46_DEFAULT_GAIN, device_ref);
	if (status)
		goto finish;
	status = tdme_setsfr_request_sync(
		1, (sfr_address = CA8210_SFR_LNAGX47),
		LNAGX47_DEFAULT_GAIN, device_ref);
	if (status)
		goto finish;
	/* Preamble Timing Config */
	status = tdme_setsfr_request_sync(
		1, (sfr_address = CA8210_SFR_PRECFG),
		*((u8 *)&pre_cfg_value), device_ref);
	if (status)
		goto finish;
	/* Preamble Threshold High */
	status = tdme_setsfr_request_sync(
		1, (sfr_address = CA8210_SFR_PTHRH),
		PTHRH_DEFAULT_THRESHOLD, device_ref);
	if (status)
		goto finish;
	/* Tx Output Power 8 dBm */
	status = tdme_setsfr_request_sync(
		0, (sfr_address = CA8210_SFR_PACFGIB),
		PACFGIB_DEFAULT_CURRENT, device_ref);
	if (status)
		goto finish;

finish:
	if (status != IEEE802154_SUCCESS) {
		dev_err(
			&spi->dev,
			"failed to set sfr at %#03x, status = %#03x\n",
			sfr_address,
			status
		);
	}
	return status;
}

/**
 * tdme_channelinit() - TDME Channel Register Default Initialisation Macro (Tx)
 * @channel:    802.15.4 channel to initialise chip for
 * @device_ref: Nondescript pointer to target device
 *
 * Return: 802.15.4 status code of API calls
 */
static u8 tdme_channelinit(u8 channel, void *device_ref)
{
	/* Transceiver front-end local oscillator tx two-point calibration
	 * value. Tuned for the hardware.
	 */
	u8 txcalval;

	if (channel >= 25)
		txcalval = 0xA7;
	else if (channel >= 23)
		txcalval = 0xA8;
	else if (channel >= 22)
		txcalval = 0xA9;
	else if (channel >= 20)
		txcalval = 0xAA;
	else if (channel >= 17)
		txcalval = 0xAB;
	else if (channel >= 16)
		txcalval = 0xAC;
	else if (channel >= 14)
		txcalval = 0xAD;
	else if (channel >= 12)
		txcalval = 0xAE;
	else
		txcalval = 0xAF;

	return tdme_setsfr_request_sync(
		1,
		CA8210_SFR_LOTXCAL,
		txcalval,
		device_ref
	);  /* LO Tx Cal */
}

/**
 * tdme_checkpibattribute() - Checks Attribute Values that are not checked in
 *                            MAC
 * @pib_attribute:        Attribute Number
 * @pib_attribute_length: Attribute length
 * @pib_attribute_value:  Pointer to Attribute Value
 *
 * Return: 802.15.4 status code of checks
 */
static u8 tdme_checkpibattribute(
	u8            pib_attribute,
	u8            pib_attribute_length,
	const void   *pib_attribute_value
)
{
	u8 status = IEEE802154_SUCCESS;
	u8 value;

	value  = *((u8 *)pib_attribute_value);

	switch (pib_attribute) {
	/* PHY */
	case PHY_TRANSMIT_POWER:
		if (value > 0x3F)
			status = IEEE802154_INVALID_PARAMETER;
		break;
	case PHY_CCA_MODE:
		if (value > 0x03)
			status = IEEE802154_INVALID_PARAMETER;
		break;
	/* MAC */
	case MAC_BATT_LIFE_EXT_PERIODS:
		if (value < 6 || value > 41)
			status = IEEE802154_INVALID_PARAMETER;
		break;
	case MAC_BEACON_PAYLOAD:
		if (pib_attribute_length > MAX_BEACON_PAYLOAD_LENGTH)
			status = IEEE802154_INVALID_PARAMETER;
		break;
	case MAC_BEACON_PAYLOAD_LENGTH:
		if (value > MAX_BEACON_PAYLOAD_LENGTH)
			status = IEEE802154_INVALID_PARAMETER;
		break;
	case MAC_BEACON_ORDER:
		if (value > 15)
			status = IEEE802154_INVALID_PARAMETER;
		break;
	case MAC_MAX_BE:
		if (value < 3 || value > 8)
			status = IEEE802154_INVALID_PARAMETER;
		break;
	case MAC_MAX_CSMA_BACKOFFS:
		if (value > 5)
			status = IEEE802154_INVALID_PARAMETER;
		break;
	case MAC_MAX_FRAME_RETRIES:
		if (value > 7)
			status = IEEE802154_INVALID_PARAMETER;
		break;
	case MAC_MIN_BE:
		if (value > 8)
			status = IEEE802154_INVALID_PARAMETER;
		break;
	case MAC_RESPONSE_WAIT_TIME:
		if (value < 2 || value > 64)
			status = IEEE802154_INVALID_PARAMETER;
		break;
	case MAC_SUPERFRAME_ORDER:
		if (value > 15)
			status = IEEE802154_INVALID_PARAMETER;
		break;
	/* boolean */
	case MAC_ASSOCIATED_PAN_COORD:
	case MAC_ASSOCIATION_PERMIT:
	case MAC_AUTO_REQUEST:
	case MAC_BATT_LIFE_EXT:
	case MAC_GTS_PERMIT:
	case MAC_PROMISCUOUS_MODE:
	case MAC_RX_ON_WHEN_IDLE:
	case MAC_SECURITY_ENABLED:
		if (value > 1)
			status = IEEE802154_INVALID_PARAMETER;
		break;
	/* MAC SEC */
	case MAC_AUTO_REQUEST_SECURITY_LEVEL:
		if (value > 7)
			status = IEEE802154_INVALID_PARAMETER;
		break;
	case MAC_AUTO_REQUEST_KEY_ID_MODE:
		if (value > 3)
			status = IEEE802154_INVALID_PARAMETER;
		break;
	default:
		break;
	}

	return status;
}

/**
 * tdme_settxpower() - Sets the tx power for MLME_SET phyTransmitPower
 * @txp:        Transmit Power
 * @device_ref: Nondescript pointer to target device
 *
 * Normalised to 802.15.4 Definition (6-bit, signed):
 * Bit 7-6: not used
 * Bit 5-0: tx power (-32 - +31 dB)
 *
 * Return: 802.15.4 status code of api calls
 */
static u8 tdme_settxpower(u8 txp, void *device_ref)
{
	u8 status;
	s8 txp_val;
	u8 txp_ext;
	union pa_cfg_sfr pa_cfg_val;

	/* extend from 6 to 8 bit */
	txp_ext = 0x3F & txp;
	if (txp_ext & 0x20)
		txp_ext += 0xC0;
	txp_val = (s8)txp_ext;

	if (CA8210_MAC_MPW) {
		if (txp_val > 0) {
			/* 8 dBm: ptrim = 5, itrim = +3 => +4 dBm */
			pa_cfg_val.bias_current_trim     = 3;
			pa_cfg_val.buffer_capacitor_trim = 5;
			pa_cfg_val.boost                 = 1;
		} else {
			/* 0 dBm: ptrim = 7, itrim = +3 => -6 dBm */
			pa_cfg_val.bias_current_trim     = 3;
			pa_cfg_val.buffer_capacitor_trim = 7;
			pa_cfg_val.boost                 = 0;
		}
		/* write PACFG */
		status = tdme_setsfr_request_sync(
			0,
			CA8210_SFR_PACFG,
			pa_cfg_val.paib,
			device_ref
		);
	} else {
		/* Look-Up Table for Setting Current and Frequency Trim values
		 * for desired Output Power
		 */
		if (txp_val > 8) {
			pa_cfg_val.paib = 0x3F;
		} else if (txp_val == 8) {
			pa_cfg_val.paib = 0x32;
		} else if (txp_val == 7) {
			pa_cfg_val.paib = 0x22;
		} else if (txp_val == 6) {
			pa_cfg_val.paib = 0x18;
		} else if (txp_val == 5) {
			pa_cfg_val.paib = 0x10;
		} else if (txp_val == 4) {
			pa_cfg_val.paib = 0x0C;
		} else if (txp_val == 3) {
			pa_cfg_val.paib = 0x08;
		} else if (txp_val == 2) {
			pa_cfg_val.paib = 0x05;
		} else if (txp_val == 1) {
			pa_cfg_val.paib = 0x03;
		} else if (txp_val == 0) {
			pa_cfg_val.paib = 0x01;
		} else { /* < 0 */
			pa_cfg_val.paib = 0x00;
		}
		/* write PACFGIB */
		status = tdme_setsfr_request_sync(
			0,
			CA8210_SFR_PACFGIB,
			pa_cfg_val.paib,
			device_ref
		);
	}

	return status;
}

/**
 * mcps_data_request() - mcps_data_request (Send Data) according to API Spec
 * @src_addr_mode:    Source Addressing Mode
 * @dst_address_mode: Destination Addressing Mode
 * @dst_pan_id:       Destination PAN ID
 * @dst_addr:         Pointer to Destination Address
 * @msdu_length:      length of Data
 * @msdu:             Pointer to Data
 * @msdu_handle:      Handle of Data
 * @tx_options:       Tx Options Bit Field
 * @security:         Pointer to Security Structure or NULL
 * @device_ref:       Nondescript pointer to target device
 *
 * Return: 802.15.4 status code of action
 */
static u8 mcps_data_request(
	u8               src_addr_mode,
	u8               dst_address_mode,
	u16              dst_pan_id,
	union macaddr   *dst_addr,
	u8               msdu_length,
	u8              *msdu,
	u8               msdu_handle,
	u8               tx_options,
	struct secspec  *security,
	void            *device_ref
)
{
	struct secspec *psec;
	struct mac_message command;

	command.command_id = SPI_MCPS_DATA_REQUEST;
	command.pdata.data_req.src_addr_mode = src_addr_mode;
	command.pdata.data_req.dst.mode = dst_address_mode;
	if (dst_address_mode != MAC_MODE_NO_ADDR) {
		command.pdata.data_req.dst.pan_id[0] = LS_BYTE(dst_pan_id);
		command.pdata.data_req.dst.pan_id[1] = MS_BYTE(dst_pan_id);
		if (dst_address_mode == MAC_MODE_SHORT_ADDR) {
			command.pdata.data_req.dst.address[0] = LS_BYTE(
				dst_addr->short_address
			);
			command.pdata.data_req.dst.address[1] = MS_BYTE(
				dst_addr->short_address
			);
		} else {   /* MAC_MODE_LONG_ADDR*/
			memcpy(
				command.pdata.data_req.dst.address,
				dst_addr->ieee_address,
				8
			);
		}
	}
	command.pdata.data_req.msdu_length = msdu_length;
	command.pdata.data_req.msdu_handle = msdu_handle;
	command.pdata.data_req.tx_options = tx_options;
	memcpy(command.pdata.data_req.msdu, msdu, msdu_length);
	psec = (struct secspec *)(command.pdata.data_req.msdu + msdu_length);
	command.length = sizeof(struct mcps_data_request_pset) -
		MAX_DATA_SIZE + msdu_length;
	if (!security || security->security_level == 0) {
		psec->security_level = 0;
		command.length += 1;
	} else {
		*psec = *security;
		command.length += sizeof(struct secspec);
	}

	if (ca8210_spi_transfer(device_ref, &command.command_id,
				command.length + 2))
		return IEEE802154_SYSTEM_ERROR;

	return IEEE802154_SUCCESS;
}

/**
 * mlme_reset_request_sync() - MLME_RESET_request/confirm according to API Spec
 * @set_default_pib: Set defaults in PIB
 * @device_ref:      Nondescript pointer to target device
 *
 * Return: 802.15.4 status code of MLME-RESET.confirm
 */
static u8 mlme_reset_request_sync(
	u8    set_default_pib,
	void *device_ref
)
{
	u8 status;
	struct mac_message command, response;
	struct spi_device *spi = device_ref;

	command.command_id = SPI_MLME_RESET_REQUEST;
	command.length = 1;
	command.pdata.u8param = set_default_pib;

	if (cascoda_api_downstream(
		&command.command_id,
		command.length + 2,
		&response.command_id,
		device_ref)) {
		dev_err(&spi->dev, "cascoda_api_downstream failed\n");
		return IEEE802154_SYSTEM_ERROR;
	}

	if (response.command_id != SPI_MLME_RESET_CONFIRM)
		return IEEE802154_SYSTEM_ERROR;

	status = response.pdata.status;

	/* reset COORD Bit for Channel Filtering as Coordinator */
	if (CA8210_MAC_WORKAROUNDS && set_default_pib && !status) {
		status = tdme_setsfr_request_sync(
			0,
			CA8210_SFR_MACCON,
			0,
			device_ref
		);
	}

	return status;
}

/**
 * mlme_set_request_sync() - MLME_SET_request/confirm according to API Spec
 * @pib_attribute:        Attribute Number
 * @pib_attribute_index:  Index within Attribute if an Array
 * @pib_attribute_length: Attribute length
 * @pib_attribute_value:  Pointer to Attribute Value
 * @device_ref:           Nondescript pointer to target device
 *
 * Return: 802.15.4 status code of MLME-SET.confirm
 */
static u8 mlme_set_request_sync(
	u8            pib_attribute,
	u8            pib_attribute_index,
	u8            pib_attribute_length,
	const void   *pib_attribute_value,
	void         *device_ref
)
{
	u8 status;
	struct mac_message command, response;

	/* pre-check the validity of pib_attribute values that are not checked
	 * in MAC
	 */
	if (tdme_checkpibattribute(
		pib_attribute, pib_attribute_length, pib_attribute_value)) {
		return IEEE802154_INVALID_PARAMETER;
	}

	if (pib_attribute == PHY_CURRENT_CHANNEL) {
		status = tdme_channelinit(
			*((u8 *)pib_attribute_value),
			device_ref
		);
		if (status)
			return status;
	}

	if (pib_attribute == PHY_TRANSMIT_POWER) {
		return tdme_settxpower(
			*((u8 *)pib_attribute_value),
			device_ref
		);
	}

	command.command_id = SPI_MLME_SET_REQUEST;
	command.length = sizeof(struct mlme_set_request_pset) -
		MAX_ATTRIBUTE_SIZE + pib_attribute_length;
	command.pdata.set_req.pib_attribute = pib_attribute;
	command.pdata.set_req.pib_attribute_index = pib_attribute_index;
	command.pdata.set_req.pib_attribute_length = pib_attribute_length;
	memcpy(
		command.pdata.set_req.pib_attribute_value,
		pib_attribute_value,
		pib_attribute_length
	);

	if (cascoda_api_downstream(
		&command.command_id,
		command.length + 2,
		&response.command_id,
		device_ref)) {
		return IEEE802154_SYSTEM_ERROR;
	}

	if (response.command_id != SPI_MLME_SET_CONFIRM)
		return IEEE802154_SYSTEM_ERROR;

	return response.pdata.status;
}

/**
 * hwme_set_request_sync() - HWME_SET_request/confirm according to API Spec
 * @hw_attribute:        Attribute Number
 * @hw_attribute_length: Attribute length
 * @hw_attribute_value:  Pointer to Attribute Value
 * @device_ref:          Nondescript pointer to target device
 *
 * Return: 802.15.4 status code of HWME-SET.confirm
 */
static u8 hwme_set_request_sync(
	u8           hw_attribute,
	u8           hw_attribute_length,
	u8          *hw_attribute_value,
	void        *device_ref
)
{
	struct mac_message command, response;

	command.command_id = SPI_HWME_SET_REQUEST;
	command.length = 2 + hw_attribute_length;
	command.pdata.hwme_set_req.hw_attribute = hw_attribute;
	command.pdata.hwme_set_req.hw_attribute_length = hw_attribute_length;
	memcpy(
		command.pdata.hwme_set_req.hw_attribute_value,
		hw_attribute_value,
		hw_attribute_length
	);

	if (cascoda_api_downstream(
		&command.command_id,
		command.length + 2,
		&response.command_id,
		device_ref)) {
		return IEEE802154_SYSTEM_ERROR;
	}

	if (response.command_id != SPI_HWME_SET_CONFIRM)
		return IEEE802154_SYSTEM_ERROR;

	return response.pdata.hwme_set_cnf.status;
}

/**
 * hwme_get_request_sync() - HWME_GET_request/confirm according to API Spec
 * @hw_attribute:        Attribute Number
 * @hw_attribute_length: Attribute length
 * @hw_attribute_value:  Pointer to Attribute Value
 * @device_ref:          Nondescript pointer to target device
 *
 * Return: 802.15.4 status code of HWME-GET.confirm
 */
static u8 hwme_get_request_sync(
	u8           hw_attribute,
	u8          *hw_attribute_length,
	u8          *hw_attribute_value,
	void        *device_ref
)
{
	struct mac_message command, response;

	command.command_id = SPI_HWME_GET_REQUEST;
	command.length = 1;
	command.pdata.hwme_get_req.hw_attribute = hw_attribute;

	if (cascoda_api_downstream(
		&command.command_id,
		command.length + 2,
		&response.command_id,
		device_ref)) {
		return IEEE802154_SYSTEM_ERROR;
	}

	if (response.command_id != SPI_HWME_GET_CONFIRM)
		return IEEE802154_SYSTEM_ERROR;

	if (response.pdata.hwme_get_cnf.status == IEEE802154_SUCCESS) {
		*hw_attribute_length =
			response.pdata.hwme_get_cnf.hw_attribute_length;
		memcpy(
			hw_attribute_value,
			response.pdata.hwme_get_cnf.hw_attribute_value,
			*hw_attribute_length
		);
	}

	return response.pdata.hwme_get_cnf.status;
}

/* Network driver operation */

/**
 * ca8210_async_xmit_complete() - Called to announce that an asynchronous
 *                                transmission has finished
 * @hw:          ieee802154_hw of ca8210 that has finished exchange
 * @msduhandle:  Identifier of transmission that has completed
 * @status:      Returned 802.15.4 status code of the transmission
 *
 * Return: 0 or linux error code
 */
static int ca8210_async_xmit_complete(
	struct ieee802154_hw  *hw,
	u8                     msduhandle,
	u8                     status)
{
	struct ca8210_priv *priv = hw->priv;

	if (priv->nextmsduhandle != msduhandle) {
		dev_err(
			&priv->spi->dev,
			"Unexpected msdu_handle on data confirm, Expected %d, got %d\n",
			priv->nextmsduhandle,
			msduhandle
		);
		return -EIO;
	}

	priv->async_tx_pending = false;
	priv->nextmsduhandle++;

	if (status) {
		dev_err(
			&priv->spi->dev,
			"Link transmission unsuccessful, status = %d\n",
			status
		);
		if (status != IEEE802154_TRANSACTION_OVERFLOW) {
			ieee802154_xmit_error(priv->hw, priv->tx_skb, status);
			return 0;
		}
	}
	ieee802154_xmit_complete(priv->hw, priv->tx_skb, true);

	return 0;
}

/**
 * ca8210_skb_rx() - Contructs a properly framed socket buffer from a received
 *                   MCPS_DATA_indication
 * @hw:        ieee802154_hw that MCPS_DATA_indication was received by
 * @len:       length of MCPS_DATA_indication
 * @data_ind:  Octet array of MCPS_DATA_indication
 *
 * Called by the spi driver whenever a SAP command is received, this function
 * will ascertain whether the command is of interest to the network driver and
 * take necessary action.
 *
 * Return: 0 or linux error code
 */
static int ca8210_skb_rx(
	struct ieee802154_hw  *hw,
	size_t                 len,
	u8                    *data_ind
)
{
	struct ieee802154_hdr hdr;
	int msdulen;
	int hlen;
	u8 mpdulinkquality = data_ind[23];
	struct sk_buff *skb;
	struct ca8210_priv *priv = hw->priv;

	/* Allocate mtu size buffer for every rx packet */
	skb = dev_alloc_skb(IEEE802154_MTU + sizeof(hdr));
	if (!skb)
		return -ENOMEM;

	skb_reserve(skb, sizeof(hdr));

	msdulen = data_ind[22]; /* msdu_length */
	if (msdulen > IEEE802154_MTU) {
		dev_err(
			&priv->spi->dev,
			"received erroneously large msdu length!\n"
		);
		kfree_skb(skb);
		return -EMSGSIZE;
	}
	dev_dbg(&priv->spi->dev, "skb buffer length = %d\n", msdulen);

	if (priv->promiscuous)
		goto copy_payload;

	/* Populate hdr */
	hdr.sec.level = data_ind[29 + msdulen];
	dev_dbg(&priv->spi->dev, "security level: %#03x\n", hdr.sec.level);
	if (hdr.sec.level > 0) {
		hdr.sec.key_id_mode = data_ind[30 + msdulen];
		memcpy(&hdr.sec.extended_src, &data_ind[31 + msdulen], 8);
		hdr.sec.key_id = data_ind[39 + msdulen];
	}
	hdr.source.mode = data_ind[0];
	dev_dbg(&priv->spi->dev, "srcAddrMode: %#03x\n", hdr.source.mode);
	hdr.source.pan_id = *(u16 *)&data_ind[1];
	dev_dbg(&priv->spi->dev, "srcPanId: %#06x\n", hdr.source.pan_id);
	memcpy(&hdr.source.extended_addr, &data_ind[3], 8);
	hdr.dest.mode = data_ind[11];
	dev_dbg(&priv->spi->dev, "dstAddrMode: %#03x\n", hdr.dest.mode);
	hdr.dest.pan_id = *(u16 *)&data_ind[12];
	dev_dbg(&priv->spi->dev, "dstPanId: %#06x\n", hdr.dest.pan_id);
	memcpy(&hdr.dest.extended_addr, &data_ind[14], 8);

	/* Fill in FC implicitly */
	hdr.fc.type = 1; /* Data frame */
	if (hdr.sec.level)
		hdr.fc.security_enabled = 1;
	else
		hdr.fc.security_enabled = 0;
	if (data_ind[1] != data_ind[12] || data_ind[2] != data_ind[13])
		hdr.fc.intra_pan = 1;
	else
		hdr.fc.intra_pan = 0;
	hdr.fc.dest_addr_mode = hdr.dest.mode;
	hdr.fc.source_addr_mode = hdr.source.mode;

	/* Add hdr to front of buffer */
	hlen = ieee802154_hdr_push(skb, &hdr);

	if (hlen < 0) {
		dev_crit(&priv->spi->dev, "failed to push mac hdr onto skb!\n");
		kfree_skb(skb);
		return hlen;
	}

	skb_reset_mac_header(skb);
	skb->mac_len = hlen;

copy_payload:
	/* Add <msdulen> bytes of space to the back of the buffer */
	/* Copy msdu to skb */
	skb_put_data(skb, &data_ind[29], msdulen);

	ieee802154_rx_irqsafe(hw, skb, mpdulinkquality);
	return 0;
}

/**
 * ca8210_net_rx() - Acts upon received SAP commands relevant to the network
 *                   driver
 * @hw:       ieee802154_hw that command was received by
 * @command:  Octet array of received command
 * @len:      length of the received command
 *
 * Called by the spi driver whenever a SAP command is received, this function
 * will ascertain whether the command is of interest to the network driver and
 * take necessary action.
 *
 * Return: 0 or linux error code
 */
static int ca8210_net_rx(struct ieee802154_hw *hw, u8 *command, size_t len)
{
	struct ca8210_priv *priv = hw->priv;
	unsigned long flags;
	u8 status;

	dev_dbg(&priv->spi->dev, "%s: CmdID = %d\n", __func__, command[0]);

	if (command[0] == SPI_MCPS_DATA_INDICATION) {
		/* Received data */
		spin_lock_irqsave(&priv->lock, flags);
		if (command[26] == priv->last_dsn) {
			dev_dbg(
				&priv->spi->dev,
				"DSN %d resend received, ignoring...\n",
				command[26]
			);
			spin_unlock_irqrestore(&priv->lock, flags);
			return 0;
		}
		priv->last_dsn = command[26];
		spin_unlock_irqrestore(&priv->lock, flags);
		return ca8210_skb_rx(hw, len - 2, command + 2);
	} else if (command[0] == SPI_MCPS_DATA_CONFIRM) {
		status = command[3];
		if (priv->async_tx_pending) {
			return ca8210_async_xmit_complete(
				hw,
				command[2],
				status
			);
		}
	}

	return 0;
}

/**
 * ca8210_skb_tx() - Transmits a given socket buffer using the ca8210
 * @skb:         Socket buffer to transmit
 * @msduhandle:  Data identifier to pass to the 802.15.4 MAC
 * @priv:        Pointer to private data section of target ca8210
 *
 * Return: 0 or linux error code
 */
static int ca8210_skb_tx(
	struct sk_buff      *skb,
	u8                   msduhandle,
	struct ca8210_priv  *priv
)
{
	struct ieee802154_hdr header = { };
	struct secspec secspec;
	int mac_len, status;

	dev_dbg(&priv->spi->dev, "%s called\n", __func__);

	/* Get addressing info from skb - ieee802154 layer creates a full
	 * packet
	 */
	mac_len = ieee802154_hdr_peek_addrs(skb, &header);
	if (mac_len < 0)
		return mac_len;

	secspec.security_level = header.sec.level;
	secspec.key_id_mode = header.sec.key_id_mode;
	if (secspec.key_id_mode == 2)
		memcpy(secspec.key_source, &header.sec.short_src, 4);
	else if (secspec.key_id_mode == 3)
		memcpy(secspec.key_source, &header.sec.extended_src, 8);
	secspec.key_index = header.sec.key_id;

	/* Pass to Cascoda API */
	status =  mcps_data_request(
		header.source.mode,
		header.dest.mode,
		header.dest.pan_id,
		(union macaddr *)&header.dest.extended_addr,
		skb->len - mac_len,
		&skb->data[mac_len],
		msduhandle,
		header.fc.ack_request,
		&secspec,
		priv->spi
	);
	return link_to_linux_err(status);
}

/**
 * ca8210_start() - Starts the network driver
 * @hw:  ieee802154_hw of ca8210 being started
 *
 * Return: 0 or linux error code
 */
static int ca8210_start(struct ieee802154_hw *hw)
{
	int status;
	u8 rx_on_when_idle;
	u8 lqi_threshold = 0;
	struct ca8210_priv *priv = hw->priv;

	priv->last_dsn = -1;
	/* Turn receiver on when idle for now just to test rx */
	rx_on_when_idle = 1;
	status = mlme_set_request_sync(
		MAC_RX_ON_WHEN_IDLE,
		0,
		1,
		&rx_on_when_idle,
		priv->spi
	);
	if (status) {
		dev_crit(
			&priv->spi->dev,
			"Setting rx_on_when_idle failed, status = %d\n",
			status
		);
		return link_to_linux_err(status);
	}
	status = hwme_set_request_sync(
		HWME_LQILIMIT,
		1,
		&lqi_threshold,
		priv->spi
	);
	if (status) {
		dev_crit(
			&priv->spi->dev,
			"Setting lqilimit failed, status = %d\n",
			status
		);
		return link_to_linux_err(status);
	}

	return 0;
}

/**
 * ca8210_stop() - Stops the network driver
 * @hw:  ieee802154_hw of ca8210 being stopped
 *
 * Return: 0 or linux error code
 */
static void ca8210_stop(struct ieee802154_hw *hw)
{
}

/**
 * ca8210_xmit_async() - Asynchronously transmits a given socket buffer using
 *                       the ca8210
 * @hw:   ieee802154_hw of ca8210 to transmit from
 * @skb:  Socket buffer to transmit
 *
 * Return: 0 or linux error code
 */
static int ca8210_xmit_async(struct ieee802154_hw *hw, struct sk_buff *skb)
{
	struct ca8210_priv *priv = hw->priv;
	int status;

	dev_dbg(&priv->spi->dev, "calling %s\n", __func__);

	priv->tx_skb = skb;
	priv->async_tx_pending = true;
	status = ca8210_skb_tx(skb, priv->nextmsduhandle, priv);
	return status;
}

/**
 * ca8210_get_ed() - Returns the measured energy on the current channel at this
 *                   instant in time
 * @hw:     ieee802154_hw of target ca8210
 * @level:  Measured Energy Detect level
 *
 * Return: 0 or linux error code
 */
static int ca8210_get_ed(struct ieee802154_hw *hw, u8 *level)
{
	u8 lenvar;
	struct ca8210_priv *priv = hw->priv;

	return link_to_linux_err(
		hwme_get_request_sync(HWME_EDVALUE, &lenvar, level, priv->spi)
	);
}

/**
 * ca8210_set_channel() - Sets the current operating 802.15.4 channel of the
 *                        ca8210
 * @hw:       ieee802154_hw of target ca8210
 * @page:     Channel page to set
 * @channel:  Channel number to set
 *
 * Return: 0 or linux error code
 */
static int ca8210_set_channel(
	struct ieee802154_hw  *hw,
	u8                     page,
	u8                     channel
)
{
	u8 status;
	struct ca8210_priv *priv = hw->priv;

	status = mlme_set_request_sync(
		PHY_CURRENT_CHANNEL,
		0,
		1,
		&channel,
		priv->spi
	);
	if (status) {
		dev_err(
			&priv->spi->dev,
			"error setting channel, MLME-SET.confirm status = %d\n",
			status
		);
	}
	return link_to_linux_err(status);
}

/**
 * ca8210_set_hw_addr_filt() - Sets the address filtering parameters of the
 *                             ca8210
 * @hw:       ieee802154_hw of target ca8210
 * @filt:     Filtering parameters
 * @changed:  Bitmap representing which parameters to change
 *
 * Effectively just sets the actual addressing information identifying this node
 * as all filtering is performed by the ca8210 as detailed in the IEEE 802.15.4
 * 2006 specification.
 *
 * Return: 0 or linux error code
 */
static int ca8210_set_hw_addr_filt(
	struct ieee802154_hw            *hw,
	struct ieee802154_hw_addr_filt  *filt,
	unsigned long                    changed
)
{
	u8 status = 0;
	struct ca8210_priv *priv = hw->priv;

	if (changed & IEEE802154_AFILT_PANID_CHANGED) {
		status = mlme_set_request_sync(
			MAC_PAN_ID,
			0,
			2,
			&filt->pan_id, priv->spi
		);
		if (status) {
			dev_err(
				&priv->spi->dev,
				"error setting pan id, MLME-SET.confirm status = %d",
				status
			);
			return link_to_linux_err(status);
		}
	}
	if (changed & IEEE802154_AFILT_SADDR_CHANGED) {
		status = mlme_set_request_sync(
			MAC_SHORT_ADDRESS,
			0,
			2,
			&filt->short_addr, priv->spi
		);
		if (status) {
			dev_err(
				&priv->spi->dev,
				"error setting short address, MLME-SET.confirm status = %d",
				status
			);
			return link_to_linux_err(status);
		}
	}
	if (changed & IEEE802154_AFILT_IEEEADDR_CHANGED) {
		status = mlme_set_request_sync(
			NS_IEEE_ADDRESS,
			0,
			8,
			&filt->ieee_addr,
			priv->spi
		);
		if (status) {
			dev_err(
				&priv->spi->dev,
				"error setting ieee address, MLME-SET.confirm status = %d",
				status
			);
			return link_to_linux_err(status);
		}
	}
	/* TODO: Should use MLME_START to set coord bit? */
	return 0;
}

/**
 * ca8210_set_tx_power() - Sets the transmit power of the ca8210
 * @hw:   ieee802154_hw of target ca8210
 * @mbm:  Transmit power in mBm (dBm*100)
 *
 * Return: 0 or linux error code
 */
static int ca8210_set_tx_power(struct ieee802154_hw *hw, s32 mbm)
{
	struct ca8210_priv *priv = hw->priv;

	mbm /= 100;
	return link_to_linux_err(
		mlme_set_request_sync(PHY_TRANSMIT_POWER, 0, 1, &mbm, priv->spi)
	);
}

/**
 * ca8210_set_cca_mode() - Sets the clear channel assessment mode of the ca8210
 * @hw:   ieee802154_hw of target ca8210
 * @cca:  CCA mode to set
 *
 * Return: 0 or linux error code
 */
static int ca8210_set_cca_mode(
	struct ieee802154_hw       *hw,
	const struct wpan_phy_cca  *cca
)
{
	u8 status;
	u8 cca_mode;
	struct ca8210_priv *priv = hw->priv;

	cca_mode = cca->mode & 3;
	if (cca_mode == 3 && cca->opt == NL802154_CCA_OPT_ENERGY_CARRIER_OR) {
		/* cca_mode 0 == CS OR ED, 3 == CS AND ED */
		cca_mode = 0;
	}
	status = mlme_set_request_sync(
		PHY_CCA_MODE,
		0,
		1,
		&cca_mode,
		priv->spi
	);
	if (status) {
		dev_err(
			&priv->spi->dev,
			"error setting cca mode, MLME-SET.confirm status = %d",
			status
		);
	}
	return link_to_linux_err(status);
}

/**
 * ca8210_set_cca_ed_level() - Sets the CCA ED level of the ca8210
 * @hw:     ieee802154_hw of target ca8210
 * @level:  ED level to set (in mbm)
 *
 * Sets the minimum threshold of measured energy above which the ca8210 will
 * back off and retry a transmission.
 *
 * Return: 0 or linux error code
 */
static int ca8210_set_cca_ed_level(struct ieee802154_hw *hw, s32 level)
{
	u8 status;
	u8 ed_threshold = (level / 100) * 2 + 256;
	struct ca8210_priv *priv = hw->priv;

	status = hwme_set_request_sync(
		HWME_EDTHRESHOLD,
		1,
		&ed_threshold,
		priv->spi
	);
	if (status) {
		dev_err(
			&priv->spi->dev,
			"error setting ed threshold, HWME-SET.confirm status = %d",
			status
		);
	}
	return link_to_linux_err(status);
}

/**
 * ca8210_set_csma_params() - Sets the CSMA parameters of the ca8210
 * @hw:       ieee802154_hw of target ca8210
 * @min_be:   Minimum backoff exponent when backing off a transmission
 * @max_be:   Maximum backoff exponent when backing off a transmission
 * @retries:  Number of times to retry after backing off
 *
 * Return: 0 or linux error code
 */
static int ca8210_set_csma_params(
	struct ieee802154_hw  *hw,
	u8                     min_be,
	u8                     max_be,
	u8                     retries
)
{
	u8 status;
	struct ca8210_priv *priv = hw->priv;

	status = mlme_set_request_sync(MAC_MIN_BE, 0, 1, &min_be, priv->spi);
	if (status) {
		dev_err(
			&priv->spi->dev,
			"error setting min be, MLME-SET.confirm status = %d",
			status
		);
		return link_to_linux_err(status);
	}
	status = mlme_set_request_sync(MAC_MAX_BE, 0, 1, &max_be, priv->spi);
	if (status) {
		dev_err(
			&priv->spi->dev,
			"error setting max be, MLME-SET.confirm status = %d",
			status
		);
		return link_to_linux_err(status);
	}
	status = mlme_set_request_sync(
		MAC_MAX_CSMA_BACKOFFS,
		0,
		1,
		&retries,
		priv->spi
	);
	if (status) {
		dev_err(
			&priv->spi->dev,
			"error setting max csma backoffs, MLME-SET.confirm status = %d",
			status
		);
	}
	return link_to_linux_err(status);
}

/**
 * ca8210_set_frame_retries() - Sets the maximum frame retries of the ca8210
 * @hw:       ieee802154_hw of target ca8210
 * @retries:  Number of retries
 *
 * Sets the number of times to retry a transmission if no acknowledgment was
 * received from the other end when one was requested.
 *
 * Return: 0 or linux error code
 */
static int ca8210_set_frame_retries(struct ieee802154_hw *hw, s8 retries)
{
	u8 status;
	struct ca8210_priv *priv = hw->priv;

	status = mlme_set_request_sync(
		MAC_MAX_FRAME_RETRIES,
		0,
		1,
		&retries,
		priv->spi
	);
	if (status) {
		dev_err(
			&priv->spi->dev,
			"error setting frame retries, MLME-SET.confirm status = %d",
			status
		);
	}
	return link_to_linux_err(status);
}

static int ca8210_set_promiscuous_mode(struct ieee802154_hw *hw, const bool on)
{
	u8 status;
	struct ca8210_priv *priv = hw->priv;

	status = mlme_set_request_sync(
		MAC_PROMISCUOUS_MODE,
		0,
		1,
		(const void *)&on,
		priv->spi
	);
	if (status) {
		dev_err(
			&priv->spi->dev,
			"error setting promiscuous mode, MLME-SET.confirm status = %d",
			status
		);
	} else {
		priv->promiscuous = on;
	}
	return link_to_linux_err(status);
}

static const struct ieee802154_ops ca8210_phy_ops = {
	.start = ca8210_start,
	.stop = ca8210_stop,
	.xmit_async = ca8210_xmit_async,
	.ed = ca8210_get_ed,
	.set_channel = ca8210_set_channel,
	.set_hw_addr_filt = ca8210_set_hw_addr_filt,
	.set_txpower = ca8210_set_tx_power,
	.set_cca_mode = ca8210_set_cca_mode,
	.set_cca_ed_level = ca8210_set_cca_ed_level,
	.set_csma_params = ca8210_set_csma_params,
	.set_frame_retries = ca8210_set_frame_retries,
	.set_promiscuous_mode = ca8210_set_promiscuous_mode
};

/* Test/EVBME Interface */

/**
 * ca8210_test_int_open() - Opens the test interface to the userspace
 * @inodp:  inode representation of file interface
 * @filp:   file interface
 *
 * Return: 0 or linux error code
 */
static int ca8210_test_int_open(struct inode *inodp, struct file *filp)
{
	struct ca8210_priv *priv = inodp->i_private;

	filp->private_data = priv;
	return 0;
}

/**
 * ca8210_test_check_upstream() - Checks a command received from the upstream
 *                                testing interface for required action
 * @buf:        Buffer containing command to check
 * @device_ref: Nondescript pointer to target device
 *
 * Return: 0 or linux error code
 */
static int ca8210_test_check_upstream(u8 *buf, void *device_ref)
{
	int ret;
	u8 response[CA8210_SPI_BUF_SIZE];

	if (buf[0] == SPI_MLME_SET_REQUEST) {
		ret = tdme_checkpibattribute(buf[2], buf[4], buf + 5);
		if (ret) {
			response[0]  = SPI_MLME_SET_CONFIRM;
			response[1] = 3;
			response[2] = IEEE802154_INVALID_PARAMETER;
			response[3] = buf[2];
			response[4] = buf[3];
			if (cascoda_api_upstream)
				cascoda_api_upstream(response, 5, device_ref);
			return ret;
		}
	}
	if (buf[0] == SPI_MLME_ASSOCIATE_REQUEST) {
		return tdme_channelinit(buf[2], device_ref);
	} else if (buf[0] == SPI_MLME_START_REQUEST) {
		return tdme_channelinit(buf[4], device_ref);
	} else if (
		(buf[0] == SPI_MLME_SET_REQUEST) &&
		(buf[2] == PHY_CURRENT_CHANNEL)
	) {
		return tdme_channelinit(buf[5], device_ref);
	} else if (
		(buf[0] == SPI_TDME_SET_REQUEST) &&
		(buf[2] == TDME_CHANNEL)
	) {
		return tdme_channelinit(buf[4], device_ref);
	} else if (
		(CA8210_MAC_WORKAROUNDS) &&
		(buf[0] == SPI_MLME_RESET_REQUEST) &&
		(buf[2] == 1)
	) {
		/* reset COORD Bit for Channel Filtering as Coordinator */
		return tdme_setsfr_request_sync(
			0,
			CA8210_SFR_MACCON,
			0,
			device_ref
		);
	}
	return 0;
} /* End of EVBMECheckSerialCommand() */

/**
 * ca8210_test_int_user_write() - Called by a process in userspace to send a
 *                                message to the ca8210 drivers
 * @filp:    file interface
 * @in_buf:  Buffer containing message to write
 * @len:     length of message
 * @off:     file offset
 *
 * Return: 0 or linux error code
 */
static ssize_t ca8210_test_int_user_write(
	struct file        *filp,
	const char __user  *in_buf,
	size_t              len,
	loff_t             *off
)
{
	int ret;
	struct ca8210_priv *priv = filp->private_data;
	u8 command[CA8210_SPI_BUF_SIZE];

	memset(command, SPI_IDLE, 6);
	if (len > CA8210_SPI_BUF_SIZE || len < 2) {
		dev_warn(
			&priv->spi->dev,
			"userspace requested erroneous write length (%zu)\n",
			len
		);
		return -EBADE;
	}

	ret = copy_from_user(command, in_buf, len);
	if (ret) {
		dev_err(
			&priv->spi->dev,
			"%d bytes could not be copied from userspace\n",
			ret
		);
		return -EIO;
	}
	if (len != command[1] + 2) {
		dev_err(
			&priv->spi->dev,
			"write len does not match packet length field\n"
		);
		return -EBADE;
	}

	ret = ca8210_test_check_upstream(command, priv->spi);
	if (ret == 0) {
		ret = ca8210_spi_exchange(
			command,
			command[1] + 2,
			NULL,
			priv->spi
		);
		if (ret < 0) {
			/* effectively 0 bytes were written successfully */
			dev_err(
				&priv->spi->dev,
				"spi exchange failed\n"
			);
			return ret;
		}
		if (command[0] & SPI_SYN)
			priv->sync_down++;
	}

	return len;
}

/**
 * ca8210_test_int_user_read() - Called by a process in userspace to read a
 *                               message from the ca8210 drivers
 * @filp:  file interface
 * @buf:   Buffer to write message to
 * @len:   length of message to read (ignored)
 * @offp:  file offset
 *
 * If the O_NONBLOCK flag was set when opening the file then this function will
 * not block, i.e. it will return if the fifo is empty. Otherwise the function
 * will block, i.e. wait until new data arrives.
 *
 * Return: number of bytes read
 */
static ssize_t ca8210_test_int_user_read(
	struct file  *filp,
	char __user  *buf,
	size_t        len,
	loff_t       *offp
)
{
	int i, cmdlen;
	struct ca8210_priv *priv = filp->private_data;
	unsigned char *fifo_buffer;
	unsigned long bytes_not_copied;

	if (filp->f_flags & O_NONBLOCK) {
		/* Non-blocking mode */
		if (kfifo_is_empty(&priv->test.up_fifo))
			return 0;
	} else {
		/* Blocking mode */
		wait_event_interruptible(
			priv->test.readq,
			!kfifo_is_empty(&priv->test.up_fifo)
		);
	}

	if (kfifo_out(&priv->test.up_fifo, &fifo_buffer, 4) != 4) {
		dev_err(
			&priv->spi->dev,
			"test_interface: Wrong number of elements popped from upstream fifo\n"
		);
		return 0;
	}
	cmdlen = fifo_buffer[1];
	bytes_not_copied = cmdlen + 2;

	bytes_not_copied = copy_to_user(buf, fifo_buffer, bytes_not_copied);
	if (bytes_not_copied > 0) {
		dev_err(
			&priv->spi->dev,
			"%lu bytes could not be copied to user space!\n",
			bytes_not_copied
		);
	}

	dev_dbg(&priv->spi->dev, "test_interface: Cmd len = %d\n", cmdlen);

	dev_dbg(&priv->spi->dev, "test_interface: Read\n");
	for (i = 0; i < cmdlen + 2; i++)
		dev_dbg(&priv->spi->dev, "%#03x\n", fifo_buffer[i]);

	kfree(fifo_buffer);

	return cmdlen + 2;
}

/**
 * ca8210_test_int_ioctl() - Called by a process in userspace to enact an
 *                           arbitrary action
 * @filp:        file interface
 * @ioctl_num:   which action to enact
 * @ioctl_param: arbitrary parameter for the action
 *
 * Return: status
 */
static long ca8210_test_int_ioctl(
	struct file *filp,
	unsigned int ioctl_num,
	unsigned long ioctl_param
)
{
	struct ca8210_priv *priv = filp->private_data;

	switch (ioctl_num) {
	case CA8210_IOCTL_HARD_RESET:
		ca8210_reset_send(priv->spi, ioctl_param);
		break;
	default:
		break;
	}
	return 0;
}

/**
 * ca8210_test_int_poll() - Called by a process in userspace to determine which
 *                          actions are currently possible for the file
 * @filp:   file interface
 * @ptable: poll table
 *
 * Return: set of poll return flags
 */
static __poll_t ca8210_test_int_poll(
	struct file *filp,
	struct poll_table_struct *ptable
)
{
	__poll_t return_flags = 0;
	struct ca8210_priv *priv = filp->private_data;

	poll_wait(filp, &priv->test.readq, ptable);
	if (!kfifo_is_empty(&priv->test.up_fifo))
		return_flags |= (EPOLLIN | EPOLLRDNORM);
	if (wait_event_interruptible(
		priv->test.readq,
		!kfifo_is_empty(&priv->test.up_fifo))) {
		return EPOLLERR;
	}
	return return_flags;
}

static const struct file_operations test_int_fops = {
	.read =           ca8210_test_int_user_read,
	.write =          ca8210_test_int_user_write,
	.open =           ca8210_test_int_open,
	.release =        NULL,
	.unlocked_ioctl = ca8210_test_int_ioctl,
	.poll =           ca8210_test_int_poll
};

/* Init/Deinit */

/**
 * ca8210_get_platform_data() - Populate a ca8210_platform_data object
 * @spi_device:  Pointer to ca8210 spi device object to get data for
 * @pdata:       Pointer to ca8210_platform_data object to populate
 *
 * Return: 0 or linux error code
 */
static int ca8210_get_platform_data(
	struct spi_device *spi_device,
	struct ca8210_platform_data *pdata
)
{
	int ret = 0;

	if (!spi_device->dev.of_node)
		return -EINVAL;

	pdata->extclockenable = of_property_read_bool(
		spi_device->dev.of_node,
		"extclock-enable"
	);
	if (pdata->extclockenable) {
		ret = of_property_read_u32(
			spi_device->dev.of_node,
			"extclock-freq",
			&pdata->extclockfreq
		);
		if (ret < 0)
			return ret;

		ret = of_property_read_u32(
			spi_device->dev.of_node,
			"extclock-gpio",
			&pdata->extclockgpio
		);
	}

	return ret;
}

/**
 * ca8210_config_extern_clk() - Configure the external clock provided by the
 *                              ca8210
 * @pdata:  Pointer to ca8210_platform_data containing clock parameters
 * @spi:    Pointer to target ca8210 spi device
 * @on:	    True to turn the clock on, false to turn off
 *
 * The external clock is configured with a frequency and output pin taken from
 * the platform data.
 *
 * Return: 0 or linux error code
 */
static int ca8210_config_extern_clk(
	struct ca8210_platform_data *pdata,
	struct spi_device *spi,
	bool on
)
{
	u8 clkparam[2];

	if (on) {
		dev_info(&spi->dev, "Switching external clock on\n");
		switch (pdata->extclockfreq) {
		case SIXTEEN_MHZ:
			clkparam[0] = 1;
			break;
		case EIGHT_MHZ:
			clkparam[0] = 2;
			break;
		case FOUR_MHZ:
			clkparam[0] = 3;
			break;
		case TWO_MHZ:
			clkparam[0] = 4;
			break;
		case ONE_MHZ:
			clkparam[0] = 5;
			break;
		default:
			dev_crit(&spi->dev, "Invalid extclock-freq\n");
			return -EINVAL;
		}
		clkparam[1] = pdata->extclockgpio;
	} else {
		dev_info(&spi->dev, "Switching external clock off\n");
		clkparam[0] = 0; /* off */
		clkparam[1] = 0;
	}
	return link_to_linux_err(
		hwme_set_request_sync(HWME_SYSCLKOUT, 2, clkparam, spi)
	);
}

/**
 * ca8210_register_ext_clock() - Register ca8210's external clock with kernel
 * @spi:  Pointer to target ca8210 spi device
 *
 * Return: 0 or linux error code
 */
static int ca8210_register_ext_clock(struct spi_device *spi)
{
	struct device_node *np = spi->dev.of_node;
	struct ca8210_priv *priv = spi_get_drvdata(spi);
	struct ca8210_platform_data *pdata = spi->dev.platform_data;
	int ret = 0;

	if (!np)
		return -EFAULT;

	priv->clk = clk_register_fixed_rate(
		&spi->dev,
		np->name,
		NULL,
		0,
		pdata->extclockfreq
	);

	if (IS_ERR(priv->clk)) {
		dev_crit(&spi->dev, "Failed to register external clk\n");
		return PTR_ERR(priv->clk);
	}
	ret = of_clk_add_provider(np, of_clk_src_simple_get, priv->clk);
	if (ret) {
		clk_unregister(priv->clk);
		dev_crit(
			&spi->dev,
			"Failed to register external clock as clock provider\n"
		);
	} else {
		dev_info(&spi->dev, "External clock set as clock provider\n");
	}

	return ret;
}

/**
 * ca8210_unregister_ext_clock() - Unregister ca8210's external clock with
 *                                 kernel
 * @spi:  Pointer to target ca8210 spi device
 */
static void ca8210_unregister_ext_clock(struct spi_device *spi)
{
	struct ca8210_priv *priv = spi_get_drvdata(spi);

	if (!priv->clk)
		return

	of_clk_del_provider(spi->dev.of_node);
	clk_unregister(priv->clk);
	dev_info(&spi->dev, "External clock unregistered\n");
}

/**
 * ca8210_reset_init() - Initialise the reset input to the ca8210
 * @spi:  Pointer to target ca8210 spi device
 *
 * Return: 0 or linux error code
 */
static int ca8210_reset_init(struct spi_device *spi)
{
	int ret;
	struct ca8210_platform_data *pdata = spi->dev.platform_data;

	pdata->gpio_reset = of_get_named_gpio(
		spi->dev.of_node,
		"reset-gpio",
		0
	);

	ret = gpio_direction_output(pdata->gpio_reset, 1);
	if (ret < 0) {
		dev_crit(
			&spi->dev,
			"Reset GPIO %d did not set to output mode\n",
			pdata->gpio_reset
		);
	}

	return ret;
}

/**
 * ca8210_interrupt_init() - Initialise the irq output from the ca8210
 * @spi:  Pointer to target ca8210 spi device
 *
 * Return: 0 or linux error code
 */
static int ca8210_interrupt_init(struct spi_device *spi)
{
	int ret;
	struct ca8210_platform_data *pdata = spi->dev.platform_data;

	pdata->gpio_irq = of_get_named_gpio(
		spi->dev.of_node,
		"irq-gpio",
		0
	);

	pdata->irq_id = gpio_to_irq(pdata->gpio_irq);
	if (pdata->irq_id < 0) {
		dev_crit(
			&spi->dev,
			"Could not get irq for gpio pin %d\n",
			pdata->gpio_irq
		);
		gpio_free(pdata->gpio_irq);
		return pdata->irq_id;
	}

	ret = request_irq(
		pdata->irq_id,
		ca8210_interrupt_handler,
		IRQF_TRIGGER_FALLING,
		"ca8210-irq",
		spi_get_drvdata(spi)
	);
	if (ret) {
		dev_crit(&spi->dev, "request_irq %d failed\n", pdata->irq_id);
		gpio_unexport(pdata->gpio_irq);
		gpio_free(pdata->gpio_irq);
	}

	return ret;
}

/**
 * ca8210_dev_com_init() - Initialise the spi communication component
 * @priv:  Pointer to private data structure
 *
 * Return: 0 or linux error code
 */
static int ca8210_dev_com_init(struct ca8210_priv *priv)
{
	priv->mlme_workqueue = alloc_ordered_workqueue(
		"MLME work queue",
		WQ_UNBOUND
	);
	if (!priv->mlme_workqueue) {
		dev_crit(&priv->spi->dev, "alloc of mlme_workqueue failed!\n");
		return -ENOMEM;
	}

	priv->irq_workqueue = alloc_ordered_workqueue(
		"ca8210 irq worker",
		WQ_UNBOUND
	);
	if (!priv->irq_workqueue) {
		dev_crit(&priv->spi->dev, "alloc of irq_workqueue failed!\n");
		destroy_workqueue(priv->mlme_workqueue);
		return -ENOMEM;
	}

	return 0;
}

/**
 * ca8210_dev_com_clear() - Deinitialise the spi communication component
 * @priv:  Pointer to private data structure
 */
static void ca8210_dev_com_clear(struct ca8210_priv *priv)
{
	destroy_workqueue(priv->mlme_workqueue);
	destroy_workqueue(priv->irq_workqueue);
}

#define CA8210_MAX_TX_POWERS (9)
static const s32 ca8210_tx_powers[CA8210_MAX_TX_POWERS] = {
	800, 700, 600, 500, 400, 300, 200, 100, 0
};

#define CA8210_MAX_ED_LEVELS (21)
static const s32 ca8210_ed_levels[CA8210_MAX_ED_LEVELS] = {
	-10300, -10250, -10200, -10150, -10100, -10050, -10000, -9950, -9900,
	-9850, -9800, -9750, -9700, -9650, -9600, -9550, -9500, -9450, -9400,
	-9350, -9300
};

/**
 * ca8210_hw_setup() - Populate the ieee802154_hw phy attributes with the
 *                     ca8210's defaults
 * @ca8210_hw:  Pointer to ieee802154_hw to populate
 */
static void ca8210_hw_setup(struct ieee802154_hw *ca8210_hw)
{
	/* Support channels 11-26 */
	ca8210_hw->phy->supported.channels[0] = CA8210_VALID_CHANNELS;
	ca8210_hw->phy->supported.tx_powers_size = CA8210_MAX_TX_POWERS;
	ca8210_hw->phy->supported.tx_powers = ca8210_tx_powers;
	ca8210_hw->phy->supported.cca_ed_levels_size = CA8210_MAX_ED_LEVELS;
	ca8210_hw->phy->supported.cca_ed_levels = ca8210_ed_levels;
	ca8210_hw->phy->current_channel = 18;
	ca8210_hw->phy->current_page = 0;
	ca8210_hw->phy->transmit_power = 800;
	ca8210_hw->phy->cca.mode = NL802154_CCA_ENERGY_CARRIER;
	ca8210_hw->phy->cca.opt = NL802154_CCA_OPT_ENERGY_CARRIER_AND;
	ca8210_hw->phy->cca_ed_level = -9800;
	ca8210_hw->phy->symbol_duration = 16;
	ca8210_hw->phy->lifs_period = 40 * ca8210_hw->phy->symbol_duration;
	ca8210_hw->phy->sifs_period = 12 * ca8210_hw->phy->symbol_duration;
	ca8210_hw->flags =
		IEEE802154_HW_AFILT |
		IEEE802154_HW_OMIT_CKSUM |
		IEEE802154_HW_FRAME_RETRIES |
		IEEE802154_HW_PROMISCUOUS |
		IEEE802154_HW_CSMA_PARAMS;
	ca8210_hw->phy->flags =
		WPAN_PHY_FLAG_TXPOWER |
		WPAN_PHY_FLAG_CCA_ED_LEVEL |
		WPAN_PHY_FLAG_CCA_MODE;
}

/**
 * ca8210_test_interface_init() - Initialise the test file interface
 * @priv:  Pointer to private data structure
 *
 * Provided as an alternative to the standard linux network interface, the test
 * interface exposes a file in the filesystem (ca8210_test) that allows
 * 802.15.4 SAP Commands and Cascoda EVBME commands to be sent directly to
 * the stack.
 *
 * Return: 0 or linux error code
 */
static int ca8210_test_interface_init(struct ca8210_priv *priv)
{
	struct ca8210_test *test = &priv->test;
	char node_name[32];

	snprintf(
		node_name,
		sizeof(node_name),
		"ca8210@%d_%d",
		priv->spi->master->bus_num,
		priv->spi->chip_select
	);

	test->ca8210_dfs_spi_int = debugfs_create_file(
		node_name,
		0600, /* S_IRUSR | S_IWUSR */
		NULL,
		priv,
		&test_int_fops
	);

	debugfs_create_symlink("ca8210", NULL, node_name);
	init_waitqueue_head(&test->readq);
	return kfifo_alloc(
		&test->up_fifo,
		CA8210_TEST_INT_FIFO_SIZE,
		GFP_KERNEL
	);
}

/**
 * ca8210_test_interface_clear() - Deinitialise the test file interface
 * @priv:  Pointer to private data structure
 */
static void ca8210_test_interface_clear(struct ca8210_priv *priv)
{
	struct ca8210_test *test = &priv->test;

	debugfs_remove(test->ca8210_dfs_spi_int);
	kfifo_free(&test->up_fifo);
	dev_info(&priv->spi->dev, "Test interface removed\n");
}

/**
 * ca8210_remove() - Shut down a ca8210 upon being disconnected
 * @spi_device:  Pointer to spi device data structure
 *
 * Return: 0 or linux error code
 */
static void ca8210_remove(struct spi_device *spi_device)
{
	struct ca8210_priv *priv;
	struct ca8210_platform_data *pdata;

	dev_info(&spi_device->dev, "Removing ca8210\n");

	pdata = spi_device->dev.platform_data;
	if (pdata) {
		if (pdata->extclockenable) {
			ca8210_unregister_ext_clock(spi_device);
			ca8210_config_extern_clk(pdata, spi_device, 0);
		}
		free_irq(pdata->irq_id, spi_device->dev.driver_data);
		kfree(pdata);
		spi_device->dev.platform_data = NULL;
	}
	/* get spi_device private data */
	priv = spi_get_drvdata(spi_device);
	if (priv) {
		dev_info(
			&spi_device->dev,
			"sync_down = %d, sync_up = %d\n",
			priv->sync_down,
			priv->sync_up
		);
		ca8210_dev_com_clear(spi_device->dev.driver_data);
		if (priv->hw) {
			if (priv->hw_registered)
				ieee802154_unregister_hw(priv->hw);
			ieee802154_free_hw(priv->hw);
			priv->hw = NULL;
			dev_info(
				&spi_device->dev,
				"Unregistered & freed ieee802154_hw.\n"
			);
		}
		if (IS_ENABLED(CONFIG_IEEE802154_CA8210_DEBUGFS))
			ca8210_test_interface_clear(priv);
	}
}

/**
 * ca8210_probe() - Set up a connected ca8210 upon being detected by the system
 * @spi_device:  Pointer to spi device data structure
 *
 * Return: 0 or linux error code
 */
static int ca8210_probe(struct spi_device *spi_device)
{
	struct ca8210_priv *priv;
	struct ieee802154_hw *hw;
	struct ca8210_platform_data *pdata;
	int ret;

	dev_info(&spi_device->dev, "Inserting ca8210\n");

	/* allocate ieee802154_hw and private data */
	hw = ieee802154_alloc_hw(sizeof(struct ca8210_priv), &ca8210_phy_ops);
	if (!hw) {
		dev_crit(&spi_device->dev, "ieee802154_alloc_hw failed\n");
		ret = -ENOMEM;
		goto error;
	}

	priv = hw->priv;
	priv->hw = hw;
	priv->spi = spi_device;
	hw->parent = &spi_device->dev;
	spin_lock_init(&priv->lock);
	priv->async_tx_pending = false;
	priv->hw_registered = false;
	priv->sync_up = 0;
	priv->sync_down = 0;
	priv->promiscuous = false;
	priv->retries = 0;
	init_completion(&priv->ca8210_is_awake);
	init_completion(&priv->spi_transfer_complete);
	init_completion(&priv->sync_exchange_complete);
	spi_set_drvdata(priv->spi, priv);
	if (IS_ENABLED(CONFIG_IEEE802154_CA8210_DEBUGFS)) {
		cascoda_api_upstream = ca8210_test_int_driver_write;
		ca8210_test_interface_init(priv);
	} else {
		cascoda_api_upstream = NULL;
	}
	ca8210_hw_setup(hw);
	ieee802154_random_extended_addr(&hw->phy->perm_extended_addr);

	pdata = kmalloc(sizeof(*pdata), GFP_KERNEL);
	if (!pdata) {
		ret = -ENOMEM;
		goto error;
	}

	priv->spi->dev.platform_data = pdata;
	ret = ca8210_get_platform_data(priv->spi, pdata);
	if (ret) {
		dev_crit(&spi_device->dev, "ca8210_get_platform_data failed\n");
		goto error;
	}

	ret = ca8210_dev_com_init(priv);
	if (ret) {
		dev_crit(&spi_device->dev, "ca8210_dev_com_init failed\n");
		goto error;
	}
	ret = ca8210_reset_init(priv->spi);
	if (ret) {
		dev_crit(&spi_device->dev, "ca8210_reset_init failed\n");
		goto error;
	}

	ret = ca8210_interrupt_init(priv->spi);
	if (ret) {
		dev_crit(&spi_device->dev, "ca8210_interrupt_init failed\n");
		goto error;
	}

	msleep(100);

	ca8210_reset_send(priv->spi, 1);

	ret = tdme_chipinit(priv->spi);
	if (ret) {
		dev_crit(&spi_device->dev, "tdme_chipinit failed\n");
		goto error;
	}

	if (pdata->extclockenable) {
		ret = ca8210_config_extern_clk(pdata, priv->spi, 1);
		if (ret) {
			dev_crit(
				&spi_device->dev,
				"ca8210_config_extern_clk failed\n"
			);
			goto error;
		}
		ret = ca8210_register_ext_clock(priv->spi);
		if (ret) {
			dev_crit(
				&spi_device->dev,
				"ca8210_register_ext_clock failed\n"
			);
			goto error;
		}
	}

	ret = ieee802154_register_hw(hw);
	if (ret) {
		dev_crit(&spi_device->dev, "ieee802154_register_hw failed\n");
		goto error;
	}
	priv->hw_registered = true;

	return 0;
error:
	msleep(100); /* wait for pending spi transfers to complete */
	ca8210_remove(spi_device);
	return link_to_linux_err(ret);
}

static const struct of_device_id ca8210_of_ids[] = {
	{.compatible = "cascoda,ca8210", },
	{},
};
MODULE_DEVICE_TABLE(of, ca8210_of_ids);

static struct spi_driver ca8210_spi_driver = {
	.driver = {
		.name =                 DRIVER_NAME,
		.owner =                THIS_MODULE,
		.of_match_table =       of_match_ptr(ca8210_of_ids),
	},
	.probe  =                       ca8210_probe,
	.remove =                       ca8210_remove
};

module_spi_driver(ca8210_spi_driver);

MODULE_AUTHOR("Harry Morris <h.morris@cascoda.com>");
MODULE_DESCRIPTION("CA-8210 SoftMAC driver");
MODULE_LICENSE("Dual BSD/GPL");
MODULE_VERSION("1.0");
