[PATCH V4 12/14] spi/s3c64xx: Add support DMA engine API

[vkoul@infradead.org (Vinod Koul)]

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@samsung.com>
> Cc: Grant Likely <grant.likely@secretlab.ca>
> Signed-off-by: Kukjin Kim <kgene.kim@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.