From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wenyou Yang Subject: [v2 PATCH 10/14] spi/atmel_spi: correct 16 bits transfers using PIO Date: Tue, 4 Dec 2012 15:53:56 +0800 Message-ID: <1354607640-13229-11-git-send-email-wenyou.yang@atmel.com> References: <1354607640-13229-1-git-send-email-wenyou.yang@atmel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: richard.genoud-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, JM.Lin-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org, nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org, spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, plagnioj-sclMFOaUSTBWk0Htik3J/w@public.gmane.org To: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org Return-path: In-Reply-To: <1354607640-13229-1-git-send-email-wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: spi-devel-general-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-spi.vger.kernel.org From: Richard Genoud Signed-off-by: Richard Genoud Cc: grant.likely-s3s/WqlpOiPyB63q8FvJNQ@public.gmane.org Cc: spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org --- drivers/spi/spi-atmel.c | 46 +++++++++++++++++++++++++++++++++++++--------- 1 file changed, 37 insertions(+), 9 deletions(-) diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c index 7f624b6..9616fab 100644 --- a/drivers/spi/spi-atmel.c +++ b/drivers/spi/spi-atmel.c @@ -573,13 +573,17 @@ 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)); @@ -997,21 +1001,39 @@ 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); } @@ -1431,6 +1453,12 @@ static int atmel_spi_transfer(struct spi_device *spi, struct spi_message *msg) return -ENOPROTOOPT; } } + 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) { -- 1.7.9.5 ------------------------------------------------------------------------------ LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d