| Message ID | 20180112113802.3888-1-hdegoede@redhat.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | pwm: lpss-platform: Cleanly exit probe on boards without resources | expand |
+Cc: Mika On Fri, 2018-01-12 at 12:38 +0100, Hans de Goede wrote: > Some boards which do not use the pwm-controller have an empty or > invalid > resource-table in ACPI the for pwm-controller. Currently this causes > these > error messages to get logged: > [ 3.281966] pwm-lpss 80862288:00: invalid resource > [ 3.287098] pwm-lpss: probe of 80862288:00 failed with error -22 > > This commit silences these error messages on these boards by cleanly > exiting pwm_lpss_probe_platform() if there is no memory resource. > I don't see anything wrong with message per se. > + > + /* > + * Some boards which don't use the pwm controller have an > empty > + * resources table, so if we cannot get the resource, return > -ENODEV. > + */ > r = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + if (!r) > + return -ENODEV; But this one looks like a quirk for some platforms when other can survive without. Can we actually check this in acpi_lpss.c and prevent platform device registration at all?
Hi, On 12-01-18 14:04, Andy Shevchenko wrote: > +Cc: Mika > > On Fri, 2018-01-12 at 12:38 +0100, Hans de Goede wrote: >> Some boards which do not use the pwm-controller have an empty or >> invalid >> resource-table in ACPI the for pwm-controller. Currently this causes >> these >> error messages to get logged: >> [ 3.281966] pwm-lpss 80862288:00: invalid resource >> [ 3.287098] pwm-lpss: probe of 80862288:00 failed with error -22 >> >> This commit silences these error messages on these boards by cleanly >> exiting pwm_lpss_probe_platform() if there is no memory resource. >> > > I don't see anything wrong with message per se. Given all the effort distros have done with splash-screens to give users a nice clean boot experience, we really want dmesg --level=err to not print anything unless there is a real problem with either the hardware or the kernel. (Note that plymouth will drop back to text-mode when kernel errors do show up.) >> + >> + /* >> + * Some boards which don't use the pwm controller have an >> empty >> + * resources table, so if we cannot get the resource, return >> -ENODEV. >> + */ >> r = platform_get_resource(pdev, IORESOURCE_MEM, 0); >> + if (!r) >> + return -ENODEV; > > But this one looks like a quirk for some platforms when other can > survive without. Right, this is something platform specific, but on platforms which have a proper resource for the PWM this patch is a no-op, so there is no need to do a quirk table for this, we can just silence the error and be done with it. > Can we actually check this in acpi_lpss.c and prevent platform device > registration at all? That is a good idea, it was not entirely trivial to achieve this but I've come up with a patch which does that. If that is deemed acceptable then we can go with that patch instead. Regards, Hans -- To unsubscribe from this list: send the line "unsubscribe linux-pwm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/pwm/pwm-lpss-platform.c b/drivers/pwm/pwm-lpss-platform.c index 5d6ed1507d29..5e5f4d018178 100644 --- a/drivers/pwm/pwm-lpss-platform.c +++ b/drivers/pwm/pwm-lpss-platform.c @@ -52,7 +52,14 @@ static int pwm_lpss_probe_platform(struct platform_device *pdev) return -ENODEV; info = (const struct pwm_lpss_boardinfo *)id->driver_data; + + /* + * Some boards which don't use the pwm controller have an empty + * resources table, so if we cannot get the resource, return -ENODEV. + */ r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!r) + return -ENODEV; lpwm = pwm_lpss_probe(&pdev->dev, r, info); if (IS_ERR(lpwm))
Some boards which do not use the pwm-controller have an empty or invalid resource-table in ACPI the for pwm-controller. Currently this causes these error messages to get logged: [ 3.281966] pwm-lpss 80862288:00: invalid resource [ 3.287098] pwm-lpss: probe of 80862288:00 failed with error -22 This commit silences these error messages on these boards by cleanly exiting pwm_lpss_probe_platform() if there is no memory resource. Signed-off-by: Hans de Goede <hdegoede@redhat.com> --- drivers/pwm/pwm-lpss-platform.c | 7 +++++++ 1 file changed, 7 insertions(+)