Re: [PATCH v2] spi: pic32: Retire dma_request_slave_channel_compat()

From: Peter Ujfalusi
Date: Thu Nov 21 2019 - 04:15:46 EST




On 21/11/2019 11.14, Peter Ujfalusi wrote:
> There is no reason to use the dma_request_slave_channel_compat() as no
> filter function and parameter is provided.
>
> Switch the driver to use dma_request_chan() instead and add support for
> deferred probing against DMA channel.
>
> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
> ---
> Hi,
>
> Changes since v1:
> - Handle deferred probing against DMA channel request.
>
> Trying to crack down on the use of dma_request_slave_channel_compat() in the
> tree...
>
> Only compile tested!
>
> Regards,
> Peter
>
> drivers/spi/spi-pic32.c | 46 +++++++++++++++++++++++++++--------------
> 1 file changed, 30 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/spi/spi-pic32.c b/drivers/spi/spi-pic32.c
> index 69f517ec59c6..bb6a6643bcd3 100644
> --- a/drivers/spi/spi-pic32.c
> +++ b/drivers/spi/spi-pic32.c
> @@ -606,25 +606,30 @@ static void pic32_spi_cleanup(struct spi_device *spi)
> gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
> }
>
> -static void pic32_spi_dma_prep(struct pic32_spi *pic32s, struct device *dev)
> +static int pic32_spi_dma_prep(struct pic32_spi *pic32s, struct device *dev)
> {
> struct spi_master *master = pic32s->master;
> - dma_cap_mask_t mask;
> + int ret = 0;
>
> - dma_cap_zero(mask);
> - dma_cap_set(DMA_SLAVE, mask);
> + master->dma_rx = dma_request_chan(dev, "spi-rx");
> + if (IS_ERR(master->dma_rx)) {
> + if (PTR_ERR(master->dma_rx) == -EPROBE_DEFER)
> + ret = -EPROBE_DEFER;
> + else
> + dev_warn(dev, "RX channel not found.\n");
>
> - master->dma_rx = dma_request_slave_channel_compat(mask, NULL, NULL,
> - dev, "spi-rx");
> - if (!master->dma_rx) {
> - dev_warn(dev, "RX channel not found.\n");
> + master->dma_rx = NULL;
> goto out_err;
> }
>
> - master->dma_tx = dma_request_slave_channel_compat(mask, NULL, NULL,
> - dev, "spi-tx");
> - if (!master->dma_tx) {
> - dev_warn(dev, "TX channel not found.\n");
> + master->dma_tx = dma_request_chan(dev, "spi-tx");
> + if (IS_ERR(master->dma_tx)) {
> + if (PTR_ERR(master->dma_tx) == -EPROBE_DEFER)
> + ret = -EPROBE_DEFER;
> + else
> + dev_warn(dev, "RX channel not found.\n");

Sigh, copy-paste :(
s/RX/TX

> +
> + master->dma_tx = NULL;
> goto out_err;
> }
>
> @@ -634,14 +639,20 @@ static void pic32_spi_dma_prep(struct pic32_spi *pic32s, struct device *dev)
> /* DMA chnls allocated and prepared */
> set_bit(PIC32F_DMA_PREP, &pic32s->flags);
>
> - return;
> + return 0;
>
> out_err:
> - if (master->dma_rx)
> + if (master->dma_rx) {
> dma_release_channel(master->dma_rx);
> + master->dma_rx = NULL;
> + }
>
> - if (master->dma_tx)
> + if (master->dma_tx) {
> dma_release_channel(master->dma_tx);
> + master->dma_tx = NULL;
> + }
> +
> + return ret;
> }
>
> static void pic32_spi_dma_unprep(struct pic32_spi *pic32s)
> @@ -776,7 +787,10 @@ static int pic32_spi_probe(struct platform_device *pdev)
> master->unprepare_transfer_hardware = pic32_spi_unprepare_hardware;
>
> /* optional DMA support */
> - pic32_spi_dma_prep(pic32s, &pdev->dev);
> + ret = pic32_spi_dma_prep(pic32s, &pdev->dev);
> + if (ret)
> + goto err_bailout;
> +
> if (test_bit(PIC32F_DMA_PREP, &pic32s->flags))
> master->can_dma = pic32_spi_can_dma;
>
>

- PÃter

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