[PATCH 12/15] spi/s3c64xx: Add support DMA engine API
Jassi Brar
jassisinghbrar at gmail.com
Mon Aug 8 13:47:58 EDT 2011
On Wed, Jul 27, 2011 at 11:01 AM, Boojin Kim <boojin.kim at samsung.com> 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>
> Acked-by: 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;
void* doesn't need typecasting (same for all such occurances)
IIRC someone already pointed it out?
> + 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);
> +}
> +
> 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);
> }
Btw, this spi driver is for S3C64xx(with pl080) and S5P(with pl330)
series, both of which
have DMAENGINE drivers. May be it could be directly switched to using
those, rather than
via Samsung's wrapper driver.
Or am I overlooking something ?
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