This is a note to let you know that I've just added the patch titled tty: serial: samsung_tty: set dma burst_size to 1 to the 5.10-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: tty-serial-samsung_tty-set-dma-burst_size-to-1.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From f7e35e4bf1e8dc2c8cbd5e0955dc1bd58558dae0 Mon Sep 17 00:00:00 2001 From: Chanho Park <chanho61.park@xxxxxxxxxxx> Date: Mon, 27 Jun 2022 15:51:13 +0900 Subject: tty: serial: samsung_tty: set dma burst_size to 1 From: Chanho Park <chanho61.park@xxxxxxxxxxx> commit f7e35e4bf1e8dc2c8cbd5e0955dc1bd58558dae0 upstream. The src_maxburst and dst_maxburst have been changed to 1 but the settings of the UCON register aren't changed yet. They should be changed as well according to the dmaengine slave config. Fixes: aa2f80e752c7 ("serial: samsung: fix maxburst parameter for DMA transactions") Cc: stable <stable@xxxxxxxxxx> Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> Signed-off-by: Chanho Park <chanho61.park@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20220627065113.139520-1-chanho61.park@xxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/tty/serial/samsung_tty.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) --- a/drivers/tty/serial/samsung_tty.c +++ b/drivers/tty/serial/samsung_tty.c @@ -361,8 +361,7 @@ static void enable_tx_dma(struct s3c24xx /* Enable tx dma mode */ ucon = rd_regl(port, S3C2410_UCON); ucon &= ~(S3C64XX_UCON_TXBURST_MASK | S3C64XX_UCON_TXMODE_MASK); - ucon |= (dma_get_cache_alignment() >= 16) ? - S3C64XX_UCON_TXBURST_16 : S3C64XX_UCON_TXBURST_1; + ucon |= S3C64XX_UCON_TXBURST_1; ucon |= S3C64XX_UCON_TXMODE_DMA; wr_regl(port, S3C2410_UCON, ucon); @@ -634,7 +633,7 @@ static void enable_rx_dma(struct s3c24xx S3C64XX_UCON_DMASUS_EN | S3C64XX_UCON_TIMEOUT_EN | S3C64XX_UCON_RXMODE_MASK); - ucon |= S3C64XX_UCON_RXBURST_16 | + ucon |= S3C64XX_UCON_RXBURST_1 | 0xf << S3C64XX_UCON_TIMEOUT_SHIFT | S3C64XX_UCON_EMPTYINT_EN | S3C64XX_UCON_TIMEOUT_EN | Patches currently in stable-queue which might be from chanho61.park@xxxxxxxxxxx are queue-5.10/tty-serial-samsung_tty-set-dma-burst_size-to-1.patch