From mboxrd@z Thu Jan 1 00:00:00 1970 From: wenyou.yang@atmel.com (Wenyou Yang) Date: Tue, 19 Mar 2013 15:47:59 +0800 Subject: [PATCH v7 09/14] spi/spi-atmel: correct 16 bits transfers using PIO In-Reply-To: <1363678866-3567-1-git-send-email-wenyou.yang@atmel.com> References: <1363678866-3567-1-git-send-email-wenyou.yang@atmel.com> Message-ID: <1363679279-4045-1-git-send-email-wenyou.yang@atmel.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Richard Genoud Signed-off-by: Richard Genoud Cc: spi-devel-general at lists.sourceforge.net Cc: linux-kernel at vger.kernel.org [wenyou.yang at atmel.com: submit the patch] Signed-off-by: Wenyou Yang --- drivers/spi/spi-atmel.c | 47 ++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 38 insertions(+), 9 deletions(-) diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c index d724c03..3aa3809 100644 --- a/drivers/spi/spi-atmel.c +++ b/drivers/spi/spi-atmel.c @@ -520,13 +520,17 @@ static void atmel_spi_next_xfer_pio(struct spi_master *master, } if (xfer->tx_buf) - spi_writel(as, TDR, *(u8 *)(xfer->tx_buf)); + if (xfer->bits_per_word > 8) + spi_writel(as, TDR, *(u16 *)(xfer->tx_buf)); + else + spi_writel(as, TDR, *(u8 *)(xfer->tx_buf)); else spi_writel(as, TDR, 0); dev_dbg(master->dev.parent, - " start pio xfer %p: len %u tx %p rx %p\n", - xfer, xfer->len, xfer->tx_buf, xfer->rx_buf); + " start pio xfer %p: len %u tx %p rx %p bitpw %d\n", + xfer, xfer->len, xfer->tx_buf, xfer->rx_buf, + xfer->bits_per_word); /* Enable relevant interrupts */ spi_writel(as, IER, SPI_BIT(RDRF) | SPI_BIT(OVRES)); @@ -945,21 +949,39 @@ atmel_spi_pump_pio_data(struct atmel_spi *as, struct spi_transfer *xfer) { u8 *txp; u8 *rxp; + u16 *txp16; + u16 *rxp16; unsigned long xfer_pos = xfer->len - as->current_remaining_bytes; if (xfer->rx_buf) { - rxp = ((u8 *)xfer->rx_buf) + xfer_pos; - *rxp = spi_readl(as, RDR); + if (xfer->bits_per_word > 8) { + rxp16 = (u16 *)(((u8 *)xfer->rx_buf) + xfer_pos); + *rxp16 = spi_readl(as, RDR); + } else { + rxp = ((u8 *)xfer->rx_buf) + xfer_pos; + *rxp = spi_readl(as, RDR); + } } else { spi_readl(as, RDR); } - - as->current_remaining_bytes--; + if (xfer->bits_per_word > 8) { + as->current_remaining_bytes -= 2; + if (as->current_remaining_bytes < 0) + as->current_remaining_bytes = 0; + } else { + as->current_remaining_bytes--; + } if (as->current_remaining_bytes) { if (xfer->tx_buf) { - txp = ((u8 *)xfer->tx_buf) + xfer_pos + 1; - spi_writel(as, TDR, *txp); + if (xfer->bits_per_word > 8) { + txp16 = (u16 *)(((u8 *)xfer->tx_buf) + + xfer_pos + 2); + spi_writel(as, TDR, *txp16); + } else { + txp = ((u8 *)xfer->tx_buf) + xfer_pos + 1; + spi_writel(as, TDR, *txp); + } } else { spi_writel(as, TDR, 0); } @@ -1373,6 +1395,13 @@ static int atmel_spi_transfer(struct spi_device *spi, struct spi_message *msg) } } + if (xfer->bits_per_word > 8) { + if (xfer->len % 2) { + dev_dbg(&spi->dev, "buffer len should be 16 bits aligned\n"); + return -EINVAL; + } + } + /* FIXME implement these protocol options!! */ if (xfer->speed_hz < spi->max_speed_hz) { dev_dbg(&spi->dev, "can't change speed in transfer\n"); -- 1.7.9.5