This is a note to let you know that I've just added the patch titled spi: imx: correct wml as the last sg length to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: spi-imx-correct-wml-as-the-last-sg-length.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 27dc9c921f14e759f83577ff923313fa05f6d032 Author: Robin Gong <yibin.gong@xxxxxxx> Date: Wed Oct 10 10:32:45 2018 +0000 spi: imx: correct wml as the last sg length [ Upstream commit 5ba5a3730639caddf42af11c60f3f3d99d9a5f00 ] Correct wml as the last rx sg length instead of the whole transfer length. Otherwise, mtd_stresstest will be failed as below: insmod mtd_stresstest.ko dev=0 ================================================= mtd_stresstest: MTD device: 0 mtd_stresstest: not NAND flash, assume page size is 512 bytes. mtd_stresstest: MTD device size 4194304, eraseblock size 65536, page size 512, count of eraseblocks 64, pa0 mtd_stresstest: doing operations mtd_stresstest: 0 operations done mtd_test: mtd_read from 1ff532, size 880 mtd_test: mtd_read from 20c267, size 64998 spi_master spi0: I/O Error in DMA RX m25p80 spi0.0: SPI transfer failed: -110 spi_master spi0: failed to transfer one message from queue mtd_test: error: read failed at 0x20c267 mtd_stresstest: error -110 occurred ================================================= insmod: ERROR: could not insert module mtd_stresstest.ko: Connection timed out Signed-off-by: Robin Gong <yibin.gong@xxxxxxx> Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> Stable-dep-of: 00b80ac93553 ("spi: imx: mx51-ecspi: Move some initialisation to prepare_message hook.") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index 686251e05edfe..139127e27a147 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -218,7 +218,6 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi, struct spi_transfer *transfer) { struct spi_imx_data *spi_imx = spi_master_get_devdata(master); - unsigned int bytes_per_word, i; if (!master->dma_rx) return false; @@ -226,14 +225,6 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi, if (spi_imx->slave_mode) return false; - bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word); - - for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) { - if (!(transfer->len % (i * bytes_per_word))) - break; - } - - spi_imx->wml = i; spi_imx->dynamic_burst = 0; return true; @@ -612,7 +603,7 @@ static void mx51_setup_wml(struct spi_imx_data *spi_imx) * and enable DMA request. */ - writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml) | + writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) | MX51_ECSPI_DMA_TX_WML(spi_imx->wml) | MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) | MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN | @@ -1330,12 +1321,30 @@ static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx, unsigned long timeout; struct spi_master *master = spi_imx->bitbang.master; struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg; + struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents); + unsigned int bytes_per_word, i; int ret; + /* Get the right burst length from the last sg to ensure no tail data */ + bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word); + for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) { + if (!(sg_dma_len(last_sg) % (i * bytes_per_word))) + break; + } + /* Use 1 as wml in case no available burst length got */ + if (i == 0) + i = 1; + + spi_imx->wml = i; + ret = spi_imx_dma_configure(master); if (ret) return ret; + if (!spi_imx->devtype_data->setup_wml) { + dev_err(spi_imx->dev, "No setup_wml()?\n"); + return -EINVAL; + } spi_imx->devtype_data->setup_wml(spi_imx); /*