From 6f98f25247b7ef03fb89030a3af6c0eb08132104 Mon Sep 17 00:00:00 2001 From: Alain Volmat Date: Mon, 18 Dec 2023 16:57:13 +0100 Subject: [PATCH] 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: Alain Volmat Link: https://msgid.link/r/20231218155721.359198-2-alain.volmat@foss.st.com Signed-off-by: Mark Brown --- drivers/spi/spi-stm32.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c index f48e4dcc29fc..af0c27d8d704 100644 --- a/drivers/spi/spi-stm32.c +++ b/drivers/spi/spi-stm32.c @@ -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( -- 2.20.1