[PATCH 1/2] spi: atmel: convert to dma_request_slave_channel_compat()
Yang Wenyou
wenyou.yang at atmel.com
Mon Jun 3 22:43:15 EDT 2013
Richard Genoud wrote:
> Use generic DMA DT helper.
> Platforms booting with or without DT populated are both supported.
>
> Based on Ludovic Desroches <ludovic.desroches at atmel.com> patchset
> "ARM: at91: move to generic DMA device tree binding"
>
> Signed-off-by: Richard Genoud <richard.genoud at gmail.com>
> ---
> drivers/spi/spi-atmel.c | 42 +++++++++++++++++++++++++++---------------
> 1 file changed, 27 insertions(+), 15 deletions(-)
>
> rebased on linux-next next-20130531
>
Tested on at91sam9g25ek,
Based on linux-next, next-20130603
plus Ludovic Desroches' patch "ARM: at91: dt: add header to define
at_hdmac configuration"
Tested-by: Wenyou Yang<wenyou.yang at atmel.com>
> diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
> index 31cfc87..ea1ec00 100644
> --- a/drivers/spi/spi-atmel.c
> +++ b/drivers/spi/spi-atmel.c
> @@ -424,10 +424,15 @@ static int atmel_spi_dma_slave_config(struct atmel_spi *as,
> return err;
> }
>
> -static bool filter(struct dma_chan *chan, void *slave)
> +static bool filter(struct dma_chan *chan, void *pdata)
> {
> - struct at_dma_slave *sl = slave;
> + struct atmel_spi_dma *sl_pdata = pdata;
> + struct at_dma_slave *sl;
>
> + if (!sl_pdata)
> + return false;
> +
> + sl = &sl_pdata->dma_slave;
> if (sl->dma_dev == chan->device->dev) {
> chan->private = sl;
> return true;
> @@ -438,24 +443,31 @@ static bool filter(struct dma_chan *chan, void *slave)
>
> static int atmel_spi_configure_dma(struct atmel_spi *as)
> {
> - struct at_dma_slave *sdata = &as->dma.dma_slave;
> struct dma_slave_config slave_config;
> + struct device *dev = &as->pdev->dev;
> int err;
>
> - if (sdata && sdata->dma_dev) {
> - dma_cap_mask_t mask;
> + dma_cap_mask_t mask;
> + dma_cap_zero(mask);
> + dma_cap_set(DMA_SLAVE, mask);
>
> - /* Try to grab two DMA channels */
> - dma_cap_zero(mask);
> - dma_cap_set(DMA_SLAVE, mask);
> - as->dma.chan_tx = dma_request_channel(mask, filter, sdata);
> - if (as->dma.chan_tx)
> - as->dma.chan_rx =
> - dma_request_channel(mask, filter, sdata);
> + as->dma.chan_tx = dma_request_slave_channel_compat(mask, filter,
> + &as->dma,
> + dev, "tx");
> + if (!as->dma.chan_tx) {
> + dev_err(dev,
> + "DMA TX channel not available, SPI unable to use DMA\n");
> + err = -EBUSY;
> + goto error;
> }
> - if (!as->dma.chan_rx || !as->dma.chan_tx) {
> - dev_err(&as->pdev->dev,
> - "DMA channel not available, SPI unable to use DMA\n");
> +
> + as->dma.chan_rx = dma_request_slave_channel_compat(mask, filter,
> + &as->dma,
> + dev, "rx");
> +
> + if (!as->dma.chan_rx) {
> + dev_err(dev,
> + "DMA RX channel not available, SPI unable to use DMA\n");
> err = -EBUSY;
> goto error;
> }
>
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