Wireless chipmaker Qualcomm ( QCOM ) swung to a quarterly profit and announced upbeat earnings estimates for next year, fueled by positive business developments in China and South Korea. The company posted a fourth-quarter net profit of $190 million, or 23 cents a diluted share, compared with a loss of $75 million, or 10 cents a share, in the year-earlier period. Sales rose 34% to $874 million from $651 million last year. Excluding charges related to amortization, goodwill and losses on Brazilian investments, Qualcomm's earnings jumped 63% to $250 million, or 31 cents a share, from $155 million, or 19 cents a share, last year. Pro forma sales were $840 million, up from $651 million. Wall Street analysts expected the firm to earn 27 cents a share on revenue of $811 million, on a pro forma basis.