[PATCH 2/3] spi: Add the use of DMA config operation
Kukjin Kim
kgene.kim at samsung.com
Tue Jun 19 04:47:56 EDT 2012
Boojin Kim wrote:
>
> Config operation is separated from request operation in DMA common
> operation.
> Because spi driver can change the DMA config for every transfer.
> So this patch is using the separated DMA config operation.
>
> Signed-off-by: Boojin Kim <boojin.kim at samsung.com>
> Signed-off-by: Kyoungil Kim <ki0351.kim at samsung.com>
> ---
> drivers/spi/spi-s3c64xx.c | 33 +++++++++++++++++++--------------
> 1 files changed, 19 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
> index 15f864d..f4e2341 100644
> --- a/drivers/spi/spi-s3c64xx.c
> +++ b/drivers/spi/spi-s3c64xx.c
> @@ -262,14 +262,24 @@ static void prepare_dma(struct s3c64xx_spi_dma_data
> *dma,
> unsigned len, dma_addr_t buf)
> {
> struct s3c64xx_spi_driver_data *sdd;
> - struct samsung_dma_prep_info info;
> + struct samsung_dma_prep info;
> + struct samsung_dma_config config;
>
> - if (dma->direction == DMA_DEV_TO_MEM)
> + if (dma->direction == DMA_DEV_TO_MEM) {
> sdd = container_of((void *)dma,
> struct s3c64xx_spi_driver_data, rx_dma);
> - else
> + config.direction = sdd->rx_dma.direction;
> + config.fifo = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
> + config.width = sdd->cur_bpw / 8;
> + sdd->ops->config(sdd->rx_dma.ch, &config);
> + } else {
> sdd = container_of((void *)dma,
> struct s3c64xx_spi_driver_data, tx_dma);
> + config.direction = sdd->tx_dma.direction;
> + config.fifo = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
> + config.width = sdd->cur_bpw / 8;
> + sdd->ops->config(sdd->tx_dma.ch, &config);
> + }
>
> info.cap = DMA_SLAVE;
> info.len = len;
> @@ -284,20 +294,15 @@ static void prepare_dma(struct s3c64xx_spi_dma_data
> *dma,
>
> static int acquire_dma(struct s3c64xx_spi_driver_data *sdd)
> {
> - struct samsung_dma_info info;
> + struct samsung_dma_req req;
>
> sdd->ops = samsung_dma_get_ops();
>
> - info.cap = DMA_SLAVE;
> - info.client = &s3c64xx_spi_dma_client;
> - info.width = sdd->cur_bpw / 8;
> -
> - info.direction = sdd->rx_dma.direction;
> - info.fifo = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
> - sdd->rx_dma.ch = sdd->ops->request(sdd->rx_dma.dmach, &info);
> - info.direction = sdd->tx_dma.direction;
> - info.fifo = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
> - sdd->tx_dma.ch = sdd->ops->request(sdd->tx_dma.dmach, &info);
> + req.cap = DMA_SLAVE;
> + req.client = &s3c64xx_spi_dma_client;
> +
> + sdd->rx_dma.ch = sdd->ops->request(sdd->rx_dma.dmach, &req);
> + sdd->tx_dma.ch = sdd->ops->request(sdd->tx_dma.dmach, &req);
>
> return 1;
> }
> --
> 1.7.1
Hi Grant,
I think, this is needed to support Samsung SPI with DMA and this has
dependency with other patches in this series.
If you're ok on this, please reply with your ack :) so that I can take this
series together.
Thanks.
Best regards,
Kgene.
--
Kukjin Kim <kgene.kim at samsung.com>, Senior Engineer,
SW Solution Development Team, Samsung Electronics Co., Ltd.
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