Messages in this thread | | | From | Andy Shevchenko <> | Date | Sat, 15 Jun 2019 14:43:09 +0300 | Subject | Re: [PATCH] i2c: mux-gpio: Use "mux" con_id to find channel GPIOs |
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On Sat, Jun 15, 2019 at 12:51 AM Serge Semin <fancer.lancer@gmail.com> wrote: > > Recent patch - ("i2c: mux/i801: Switch to use descriptor passing") > altered the i2c-mux-gpio driver to use the GPIO-descriptor > based interface to find and request the GPIOs then being utilized > to select and deselect the channels of GPIO-driven i2c-muxes. Even > though the proposed modification was correct for the platform_data-based > systems, it was invalid for the OF-based ones and caused the kernel > to crash at the driver probe procedure. There were two problems with > that modification. First of all the gpiod_count() and gpiod_get_index() > were called with NULL con_id.
I always thought that this means "count me all GPIO's for this device despite their names" and "get me GPIO by index despite it's name". What's went wrong?
> Due to this the methods couldn't find > the "mux-gpios" OF-properties and returned the -ENOENT error. Secondly > the return value of gpiod_count() wasn't checked for being negative, > which in case of an error caused the driver to crash. This patch > is intended to fix the described problems.
-- With Best Regards, Andy Shevchenko
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