]> git.ipfire.org Git - thirdparty/linux.git/commit
i2c: muxes: pca954x: Reset if (de)select fails
authorWojciech Siudy <wojciech.siudy@nokia.com>
Tue, 3 Jun 2025 12:47:21 +0000 (14:47 +0200)
committerWolfram Sang <wsa+renesas@sang-engineering.com>
Mon, 11 Aug 2025 18:10:09 +0000 (20:10 +0200)
commit94c29677640312fcfab261bddc1006bc43efe4ba
treef079fd4b59d2dfb22a03d2e1c1c3d48c9e439179
parent690de2902dca98aec96de004428c020ca902f047
i2c: muxes: pca954x: Reset if (de)select fails

If the channel selection or deselection times out, it indicates
a failure in the mux's I2C subsystem. Without sending a reset pulse,
a power-on-reset of the entire device would be required to restore
communication.

The datasheet specifies a minimum hold time of 4 ns for the reset
pulse, but due to the path's capacitance and themux having its own
clock, it is recommended to extend this to approximately 1 us.

Since reset controller is used, there is no need to take care of other
devices sharing the same reset line.

Signed-off-by: Wojciech Siudy <wojciech.siudy@nokia.com>
[wsa: removed superfluous prinout, unneeded braces and fixed indent]
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
drivers/i2c/muxes/i2c-mux-pca954x.c