From 3e7f335689ebfa0a68814dfe9f0588076fb9ad01 Mon Sep 17 00:00:00 2001 From: "Mark A. Greer" Date: Tue, 2 Sep 2014 15:12:18 -0700 Subject: [PATCH] NFC: trf7970a: Use spi_sync() instead of spi_write_then_read() To more efficiently handle long continuous reads, use spi_sync() instead of spi_write_then_read(). Signed-off-by: Mark A. Greer Signed-off-by: Samuel Ortiz --- drivers/nfc/trf7970a.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c index 159b0a3f965b..badd2c7ffa92 100644 --- a/drivers/nfc/trf7970a.c +++ b/drivers/nfc/trf7970a.c @@ -393,15 +393,28 @@ static int trf7970a_read(struct trf7970a *trf, u8 reg, u8 *val) return ret; } -static int trf7970a_read_cont(struct trf7970a *trf, u8 reg, - u8 *buf, size_t len) +static int trf7970a_read_cont(struct trf7970a *trf, u8 reg, u8 *buf, size_t len) { u8 addr = reg | TRF7970A_CMD_BIT_RW | TRF7970A_CMD_BIT_CONTINUOUS; + struct spi_transfer t[2]; + struct spi_message m; int ret; dev_dbg(trf->dev, "read_cont(0x%x, %zd)\n", addr, len); - ret = spi_write_then_read(trf->spi, &addr, 1, buf, len); + spi_message_init(&m); + + memset(&t, 0, sizeof(t)); + + t[0].tx_buf = &addr; + t[0].len = sizeof(addr); + spi_message_add_tail(&t[0], &m); + + t[1].rx_buf = buf; + t[1].len = len; + spi_message_add_tail(&t[1], &m); + + ret = spi_sync(trf->spi, &m); if (ret) dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr, ret); -- 2.20.1