On Wed, Sep 3, 2025 at 12:38 PM Andy Shevchenko <[email protected]> wrote: > > On Wed, Sep 03, 2025 at 12:34:00PM +0200, Bartosz Golaszewski wrote: > > On Wed, Sep 3, 2025 at 12:22 PM Andy Shevchenko > > <[email protected]> wrote: > > > On Wed, Sep 03, 2025 at 09:33:34AM +0200, Bartosz Golaszewski wrote: > > > > On Tue, Sep 2, 2025 at 10:46 PM Andy Shevchenko > > > > <[email protected]> wrote: > > > > > On Tue, Sep 2, 2025 at 8:42 PM Bartosz Golaszewski <[email protected]> > > > > > wrote: > > > > > > On Tue, Sep 2, 2025 at 4:38 PM Andy Shevchenko > > > > > > <[email protected]> wrote: > > > > > > > On Tue, Sep 02, 2025 at 01:59:25PM +0200, Bartosz Golaszewski > > > > > > > wrote: > > ... > > > > > > > > > The strict flag in struct pinmux_ops disallows the usage of the > > > > > > > > same pin > > > > > > > > as a GPIO and for another function. Without it, a rouge > > > > > > > > user-space > > > > > > > > process with enough privileges (or even a buggy driver) can > > > > > > > > request a > > > > > > > > used pin as GPIO and drive it, potentially confusing devices or > > > > > > > > even > > > > > > > > crashing the system. Set it globally for all pinctrl-msm users. > > > > > > > > > > > > > > How does this keep (or allow) I²C generic recovery mechanism to > > > > > > > work? > > > > > > > > Anyway, what is your point? I don't think it has any impact on this. > > > > > > If we have a group of pins that are marked as I²C, and we want to use > > > recovery > > > via GPIOs, would it be still possible to request as GPIO when controller > > > driver > > > is in the strict mode? > > > > Yes, if you mark that function as a "GPIO" function in the pin > > controller driver. > > How would it prevent from requesting from user space? >
It wouldn't, we don't discriminate between user-space and in-kernel GPIO users. A function either is a GPIO or isn't. Can you point me to the driver you're thinking about or is this a purely speculative question? Bartosz
