The patch spi: imx: use PIO mode if size is small has been applied to the spi tree at https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark >From 133eb8e38b02c6c63a039523fca12737009a6686 Mon Sep 17 00:00:00 2001 From: Robin Gong <yibin.gong@xxxxxxx> Date: Wed, 10 Oct 2018 10:32:48 +0000 Subject: [PATCH] spi: imx: use PIO mode if size is small Use PIO mode instead if size is smaller than fifo size, since dma may be less efficient. Signed-off-by: Robin Gong <yibin.gong@xxxxxxx> Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> --- drivers/spi/spi-imx.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index 037abbb852a4..dd1ce12aa386 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -224,6 +224,9 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi, if (spi_imx->slave_mode) return false; + if (transfer->len < spi_imx->devtype_data->fifo_size) + return false; + spi_imx->dynamic_burst = 0; return true; -- 2.19.0