From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Sascha Hauer , Mark Brown , Kamal Mostafa Subject: [PATCH 3.19.y-ckt 048/130] spi: imx: Fix small DMA transfers Date: Thu, 27 Aug 2015 15:10:39 -0700 Message-Id: <1440713521-5906-49-git-send-email-kamal@canonical.com> In-Reply-To: <1440713521-5906-1-git-send-email-kamal@canonical.com> References: <1440713521-5906-1-git-send-email-kamal@canonical.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.19.8-ckt6 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Sascha Hauer commit f6ee9b582d2db652497b73c1f117591dfb6d3a90 upstream. DMA transfers must be greater than the watermark level size. spi_imx->rx_wml and spi_imx->tx_wml contain the watermark level in 32bit words whereas struct spi_transfer contains the transfer len in bytes. Fix the check if DMA is possible for a transfer accordingly. This fixes transfers with sizes between 33 and 128 bytes for which previously was claimed that DMA is possible. Fixes: f62caccd12c17e4 (spi: spi-imx: add DMA support) Signed-off-by: Sascha Hauer Signed-off-by: Mark Brown Signed-off-by: Kamal Mostafa --- drivers/spi/spi-imx.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index 308c2d3..b9046f7 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -202,8 +202,9 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi, { struct spi_imx_data *spi_imx = spi_master_get_devdata(master); - if (spi_imx->dma_is_inited && (transfer->len > spi_imx->rx_wml) - && (transfer->len > spi_imx->tx_wml)) + if (spi_imx->dma_is_inited + && transfer->len > spi_imx->rx_wml * sizeof(u32) + && transfer->len > spi_imx->tx_wml * sizeof(u32)) return true; return false; } -- 1.9.1