Unverified Commit 6f98f252 authored by Alain Volmat's avatar Alain Volmat Committed by Mark Brown
Browse files

spi: stm32: use dma_get_slave_caps prior to configuring dma channel 



First check the dma channel capabilities (max burst) before
configuring the dma channel.

Signed-off-by: default avatarAlain Volmat <alain.volmat@foss.st.com>
Link: https://msgid.link/r/20231218155721.359198-2-alain.volmat@foss.st.com


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 15009a1b

drivers/spi/spi-stm32.c

+11 −2
Original line number Diff line number Diff line
@@ -1157,15 +1157,19 @@ static void stm32_spi_dma_rx_cb(void *data) 
 * stm32_spi_dma_config - configure dma slave channel depending on current

 *			  transfer bits_per_word.

 * @spi: pointer to the spi controller data structure

 * @dma_chan: pointer to the DMA channel

 * @dma_conf: pointer to the dma_slave_config structure

 * @dir: direction of the dma transfer

 */

static void stm32_spi_dma_config(struct stm32_spi *spi,

				 struct dma_chan *dma_chan,

				 struct dma_slave_config *dma_conf,

				 enum dma_transfer_direction dir)

{

	enum dma_slave_buswidth buswidth;

	struct dma_slave_caps caps;

	u32 maxburst;

	int ret;



	if (spi->cur_bpw <= 8)

		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
@@ -1184,6 +1188,11 @@ static void stm32_spi_dma_config(struct stm32_spi *spi, 
		maxburst = 1;

	}



	/* Get the DMA channel caps, and adjust maxburst if possible */

	ret = dma_get_slave_caps(dma_chan, &caps);

	if (!ret)

		maxburst = min(maxburst, caps.max_burst);



	memset(dma_conf, 0, sizeof(struct dma_slave_config));

	dma_conf->direction = dir;

	if (dma_conf->direction == DMA_DEV_TO_MEM) { /* RX */
@@ -1366,7 +1375,7 @@ static int stm32_spi_transfer_one_dma(struct stm32_spi *spi, 


	rx_dma_desc = NULL;

	if (spi->rx_buf && spi->dma_rx) {

		stm32_spi_dma_config(spi, &rx_dma_conf, DMA_DEV_TO_MEM);

		stm32_spi_dma_config(spi, spi->dma_rx, &rx_dma_conf, DMA_DEV_TO_MEM);

		dmaengine_slave_config(spi->dma_rx, &rx_dma_conf);



		/* Enable Rx DMA request */
@@ -1382,7 +1391,7 @@ static int stm32_spi_transfer_one_dma(struct stm32_spi *spi, 


	tx_dma_desc = NULL;

	if (spi->tx_buf && spi->dma_tx) {

		stm32_spi_dma_config(spi, &tx_dma_conf, DMA_MEM_TO_DEV);

		stm32_spi_dma_config(spi, spi->dma_tx, &tx_dma_conf, DMA_MEM_TO_DEV);

		dmaengine_slave_config(spi->dma_tx, &tx_dma_conf);



		tx_dma_desc = dmaengine_prep_slave_sg(