github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-27 08:33:17 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

net: dsa: ks8995: Add proper RESET delay

Browse Source 
According to the datasheet we need to wait 100us before accessing
any registers in the KS8995 after a reset de-assertion.

Add this delay, if and only if we obtained a GPIO descriptor,
otherwise it is just a pointless delay.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20250813-ks8995-to-dsa-v1-2-75c359ede3a5@linaro.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Linus Walleij 2025-08-13 23:43:04 +02:00 committed by Jakub Kicinski
parent 60cbe71fdb
commit ccf29cb849
1 changed files with 9 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
drivers/net/dsa/ks8995.c
View File

@ -438,9 +438,15 @@ static int ks8995_probe(struct spi_device *spi)
if (err)
return err;
/* de-assert switch reset */
/* FIXME: this likely requires a delay */
gpiod_set_value_cansleep(ks->reset_gpio, 0);
if (ks->reset_gpio) {
/*
* If a reset line was obtained, wait for 100us after
* de-asserting RESET before accessing any registers, see
* the KS8995MA datasheet, page 44.
*/
gpiod_set_value_cansleep(ks->reset_gpio, 0);
udelay(100);
}
spi_set_drvdata(spi, ks);