On Tue, Mar 8, 2016 at 3:03 PM, Dmitry Torokhov <[email protected]> wrote: > On ACPI-based systems ACPI power domain code runtime resumes device before > calling suspend method, which ensures that i2c-hid suspend code starts with > device not in low-power state and with interrupts enabled. > > On other systems, especially if device is not a part of any power domain, > we may end up calling driver's system-level suspend routine while the > device is runtime-suspended (with controller in presumably low power state > and interrupts disabled). This will result in interrupts being essentially > disabled twice, and we will only re-enable them after both system resume > and runtime resume methods complete. Unfortunately i2c_hid_resume() calls > i2c_hid_hwreset() and that only works properly if interrupts are enabled. > > Also if device is runtime-suspended driver's suspend code may fail if it > tries to issue I/O requests. > > Let's fix it by runtime-resuming the device if we need to run HID driver's > suspend code and also disabling interrupts only if device is not already > runtime-suspended. Also on resume we mark the device as running at full > power (since that is what resetting will do to it). > > Signed-off-by: Doug Anderson <[email protected]> > Signed-off-by: Dmitry Torokhov <[email protected]>
Reviewed-by: Benson Leung <[email protected]> > --- > > This is an uprev of a patch that Doug sent a year ago (see > https://patchwork.kernel.org/patch/5970731/), adjusted to the latest > mainline. The change from v2 is that we runtime-resume the device before > calling into HID driver's suspend callback. -- Benson Leung Senior Software Engineer, Chrom* OS [email protected]
