diff options
| author |   Sven Eckelmann <sven@narfation.org> | 2025-08-10 20:05:15 +0200 |
|---|---|---|
| committer |   Andi Shyti <andi.shyti@kernel.org> | 2025-08-19 20:20:02 -0100 |
| commit | ceee7776c010c5f09d30985c9e5223b363a6172a (patch) | |
| tree | de300e780993b07e1aa6bcef1aee26ac1326883c | |
| parent | i2c: rtl9300: Fix multi-byte I2C write (diff) | |
| download | wireguard-linux-ceee7776c010c5f09d30985c9e5223b363a6172a.tar.xz wireguard-linux-ceee7776c010c5f09d30985c9e5223b363a6172a.zip | |
i2c: rtl9300: Increase timeout for transfer polling
The timeout for transfers was only set to 2ms. Because of this relatively
low limit, 12-byte read operations to the frontend MCU of a RTL8239 POE PSE
chip cluster was consistently resulting in a timeout.
The original OpenWrt downstream driver [1] was not using any timeout limit
at all. This is also possible by setting the timeout_us parameter of
regmap_read_poll_timeout() to 0. But since the driver currently implements
the ETIMEDOUT error, it is more sensible to increase the timeout in such a
way that communication with the (quite common) Realtek I2C-connected POE
management solution is possible.
[1] https://git.openwrt.org/?p=openwrt/openwrt.git;a=blob;f=target/linux/realtek/files-6.12/drivers/i2c/busses/i2c-rtl9300.c;h=c4d973195ef39dc56d6207e665d279745525fcac#l202
Fixes: c366be720235 ("i2c: Add driver for the RTL9300 I2C controller")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Cc: <stable@vger.kernel.org> # v6.13+
Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Tested-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20250810-i2c-rtl9300-multi-byte-v5-3-cd9dca0db722@narfation.org
| -rw-r--r-- | drivers/i2c/busses/i2c-rtl9300.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/i2c/busses/i2c-rtl9300.c b/drivers/i2c/busses/i2c-rtl9300.c index 4a538b266080..4a282d57e2c1 100644 --- a/drivers/i2c/busses/i2c-rtl9300.c +++ b/drivers/i2c/busses/i2c-rtl9300.c @@ -175,7 +175,7 @@ static int rtl9300_i2c_execute_xfer(struct rtl9300_i2c *i2c, char read_write, return ret; ret = regmap_read_poll_timeout(i2c->regmap, i2c->reg_base + RTL9300_I2C_MST_CTRL1, - val, !(val & RTL9300_I2C_MST_CTRL1_I2C_TRIG), 100, 2000); + val, !(val & RTL9300_I2C_MST_CTRL1_I2C_TRIG), 100, 100000); if (ret) return ret; |