[PATCH V4 12/14] spi/s3c64xx: Add support DMA engine API
Vinod Koul
vkoul at infradead.org
Mon Jul 25 07:17:10 EDT 2011
On Mon, 2011-07-25 at 10:28 +0900, Boojin Kim wrote:
> This patch adds to support DMA generic API to transfer raw
> SPI data. Basiclly the spi driver uses DMA generic API if
> architecture supports it. Otherwise, uses Samsung specific
> S3C-PL330 APIs.
>
> Signed-off-by: Boojin Kim <boojin.kim at samsung.com>
> Cc: Grant Likely <grant.likely at secretlab.ca>
> Signed-off-by: Kukjin Kim <kgene.kim at samsung.com>
> ---
> drivers/spi/spi_s3c64xx.c | 141 ++++++++++++++++++++++-----------------------
> 1 files changed, 69 insertions(+), 72 deletions(-)
>
> diff --git a/drivers/spi/spi_s3c64xx.c b/drivers/spi/spi_s3c64xx.c
> index 8945e20..a4cf76a 100644
> --- a/drivers/spi/spi_s3c64xx.c
> +++ b/drivers/spi/spi_s3c64xx.c
> @@ -172,6 +172,9 @@ struct s3c64xx_spi_driver_data {
> unsigned state;
> unsigned cur_mode, cur_bpw;
> unsigned cur_speed;
> + unsigned rx_ch;
> + unsigned tx_ch;
> + struct samsung_dma_ops *ops;
> };
>
> static struct s3c2410_dma_client s3c64xx_spi_dma_client = {
> @@ -227,6 +230,38 @@ static void flush_fifo(struct s3c64xx_spi_driver_data *sdd)
> writel(val, regs + S3C64XX_SPI_CH_CFG);
> }
>
> +static void s3c64xx_spi_dma_rxcb(void *data)
> +{
> + struct s3c64xx_spi_driver_data *sdd
> + = (struct s3c64xx_spi_driver_data *)data;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&sdd->lock, flags);
> +
> + sdd->state &= ~RXBUSY;
> + /* If the other done */
> + if (!(sdd->state & TXBUSY))
> + complete(&sdd->xfer_completion);
> +
> + spin_unlock_irqrestore(&sdd->lock, flags);
> +}
> +
> +static void s3c64xx_spi_dma_txcb(void *data)
> +{
> + struct s3c64xx_spi_driver_data *sdd
> + = (struct s3c64xx_spi_driver_data *)data;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&sdd->lock, flags);
> +
> + sdd->state &= ~TXBUSY;
> + /* If the other done */
> + if (!(sdd->state & RXBUSY))
> + complete(&sdd->xfer_completion);
> +
> + spin_unlock_irqrestore(&sdd->lock, flags);
> +}
I don't see much diff in these two functions and you should be able to
use a generic one which takes care of both TX and RX, does your callback
data know if the channel is for TX or RX? If not then a helper to do
above should take care well and making code simpler
> +
> static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
> struct spi_device *spi,
> struct spi_transfer *xfer, int dma_mode)
> @@ -234,6 +269,7 @@ static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
> struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
> void __iomem *regs = sdd->regs;
> u32 modecfg, chcfg;
> + struct samsung_dma_prep_info info;
>
> modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
> modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
> @@ -259,10 +295,14 @@ static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
> chcfg |= S3C64XX_SPI_CH_TXCH_ON;
> if (dma_mode) {
> modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
> - s3c2410_dma_config(sdd->tx_dmach, sdd->cur_bpw / 8);
> - s3c2410_dma_enqueue(sdd->tx_dmach, (void *)sdd,
> - xfer->tx_dma, xfer->len);
> - s3c2410_dma_ctrl(sdd->tx_dmach, S3C2410_DMAOP_START);
> + info.cap = DMA_SLAVE;
> + info.direction = DMA_TO_DEVICE;
> + info.buf = xfer->tx_dma;
> + info.len = xfer->len;
> + info.fp = s3c64xx_spi_dma_txcb;
> + info.fp_param = sdd;
> + sdd->ops->prepare(sdd->tx_ch, &info);
> + sdd->ops->trigger(sdd->tx_ch);
> } else {
> switch (sdd->cur_bpw) {
> case 32:
> @@ -294,10 +334,14 @@ static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
> writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
> | S3C64XX_SPI_PACKET_CNT_EN,
> regs + S3C64XX_SPI_PACKET_CNT);
> - s3c2410_dma_config(sdd->rx_dmach, sdd->cur_bpw / 8);
> - s3c2410_dma_enqueue(sdd->rx_dmach, (void *)sdd,
> - xfer->rx_dma, xfer->len);
> - s3c2410_dma_ctrl(sdd->rx_dmach, S3C2410_DMAOP_START);
> + info.cap = DMA_SLAVE;
> + info.direction = DMA_FROM_DEVICE;
> + info.buf = xfer->rx_dma;
> + info.len = xfer->len;
> + info.fp = s3c64xx_spi_dma_rxcb;
> + info.fp_param = sdd;
> + sdd->ops->prepare(sdd->rx_ch, &info);
> + sdd->ops->trigger(sdd->rx_ch);
> }
> }
>
> @@ -483,46 +527,6 @@ static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
> }
> }
>
> -static void s3c64xx_spi_dma_rxcb(struct s3c2410_dma_chan *chan, void *buf_id,
> - int size, enum s3c2410_dma_buffresult res)
> -{
> - struct s3c64xx_spi_driver_data *sdd = buf_id;
> - unsigned long flags;
> -
> - spin_lock_irqsave(&sdd->lock, flags);
> -
> - if (res == S3C2410_RES_OK)
> - sdd->state &= ~RXBUSY;
> - else
> - dev_err(&sdd->pdev->dev, "DmaAbrtRx-%d\n", size);
> -
> - /* If the other done */
> - if (!(sdd->state & TXBUSY))
> - complete(&sdd->xfer_completion);
> -
> - spin_unlock_irqrestore(&sdd->lock, flags);
> -}
> -
> -static void s3c64xx_spi_dma_txcb(struct s3c2410_dma_chan *chan, void *buf_id,
> - int size, enum s3c2410_dma_buffresult res)
> -{
> - struct s3c64xx_spi_driver_data *sdd = buf_id;
> - unsigned long flags;
> -
> - spin_lock_irqsave(&sdd->lock, flags);
> -
> - if (res == S3C2410_RES_OK)
> - sdd->state &= ~TXBUSY;
> - else
> - dev_err(&sdd->pdev->dev, "DmaAbrtTx-%d \n", size);
> -
> - /* If the other done */
> - if (!(sdd->state & RXBUSY))
> - complete(&sdd->xfer_completion);
> -
> - spin_unlock_irqrestore(&sdd->lock, flags);
> -}
> -
> #define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
>
> static int s3c64xx_spi_map_mssg(struct s3c64xx_spi_driver_data *sdd,
> @@ -697,12 +701,10 @@ static void handle_msg(struct s3c64xx_spi_driver_data *sdd,
> if (use_dma) {
> if (xfer->tx_buf != NULL
> && (sdd->state & TXBUSY))
> - s3c2410_dma_ctrl(sdd->tx_dmach,
> - S3C2410_DMAOP_FLUSH);
> + sdd->ops->stop(sdd->tx_ch);
> if (xfer->rx_buf != NULL
> && (sdd->state & RXBUSY))
> - s3c2410_dma_ctrl(sdd->rx_dmach,
> - S3C2410_DMAOP_FLUSH);
> + sdd->ops->stop(sdd->rx_ch);
> }
>
> goto out;
> @@ -742,24 +744,19 @@ out:
>
> static int acquire_dma(struct s3c64xx_spi_driver_data *sdd)
> {
> - if (s3c2410_dma_request(sdd->rx_dmach,
> - &s3c64xx_spi_dma_client, NULL) < 0) {
> - dev_err(&sdd->pdev->dev, "cannot get RxDMA\n");
> - return 0;
> - }
> - s3c2410_dma_set_buffdone_fn(sdd->rx_dmach, s3c64xx_spi_dma_rxcb);
> - s3c2410_dma_devconfig(sdd->rx_dmach, S3C2410_DMASRC_HW,
> - sdd->sfr_start + S3C64XX_SPI_RX_DATA);
> -
> - if (s3c2410_dma_request(sdd->tx_dmach,
> - &s3c64xx_spi_dma_client, NULL) < 0) {
> - dev_err(&sdd->pdev->dev, "cannot get TxDMA\n");
> - s3c2410_dma_free(sdd->rx_dmach, &s3c64xx_spi_dma_client);
> - return 0;
> - }
> - s3c2410_dma_set_buffdone_fn(sdd->tx_dmach, s3c64xx_spi_dma_txcb);
> - s3c2410_dma_devconfig(sdd->tx_dmach, S3C2410_DMASRC_MEM,
> - sdd->sfr_start + S3C64XX_SPI_TX_DATA);
> +
> + struct samsung_dma_info info;
> + sdd->ops = samsung_dma_get_ops();
> +
> + info.cap = DMA_SLAVE;
> + info.client = &s3c64xx_spi_dma_client;
> + info.direction = DMA_FROM_DEVICE;
> + info.fifo = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
> + info.width = sdd->cur_bpw / 8;
> + sdd->rx_ch = sdd->ops->request(sdd->rx_dmach, &info);
> + info.direction = DMA_TO_DEVICE;
> + info.fifo = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
> + sdd->tx_ch = sdd->ops->request(sdd->tx_dmach, &info);
>
> return 1;
> }
> @@ -800,8 +797,8 @@ static void s3c64xx_spi_work(struct work_struct *work)
> spin_unlock_irqrestore(&sdd->lock, flags);
>
> /* Free DMA channels */
> - s3c2410_dma_free(sdd->tx_dmach, &s3c64xx_spi_dma_client);
> - s3c2410_dma_free(sdd->rx_dmach, &s3c64xx_spi_dma_client);
> + sdd->ops->release(sdd->rx_ch, &s3c64xx_spi_dma_client);
> + sdd->ops->release(sdd->tx_ch, &s3c64xx_spi_dma_client);
> }
>
> static int s3c64xx_spi_transfer(struct spi_device *spi,
--
~Vinod Koul
Intel Corp.
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