@@ -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(
First check the dma channel capabilities (max burst) before configuring the dma channel. Signed-off-by: Alain Volmat <alain.volmat@foss.st.com> --- drivers/spi/spi-stm32.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-)