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 5.15-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-5.15 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
@@ -378,8 +378,7 @@ 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);
@@ -675,7 +674,7 @@ 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-5.15/tty-serial-samsung_tty-set-dma-burst_size-to-1.patch
