pwm-bl: regression on all pxa platforms
Robert Jarzmik
robert.jarzmik at free.fr
Sat Sep 26 11:40:26 PDT 2015
Robert Jarzmik <robert.jarzmik at free.fr> writes:
> Hi Thierry,
>
> Since a bit of time, the PWM backlight based pxa platforms are broken.
> All of these platforms rely on a registering such as the one in [1].
>
> At least I think the commit 68feaca0b13e ("backlight: pwm: Handle EPROBE_DEFER
> while requesting the PWM") breaks my platforms because :
> (a) no pwm table is added (legacy platforms)
> (b) in this case, in pwm_get(), pmw_lookup_list is empty, and therefore chosen
> == NULL, and therefore pwm_get() returns NULL, and pwm_get() return
> -EPROBE_DEFER
> (c) as a consequence, this code is unreachable in pwm_bl.c :
> if (IS_ERR(pb->pwm)) {
> ret = PTR_ERR(pb->pwm);
> dev_info(&pdev->dev, "%s:%d(): %d\n", __func__, __LINE__, ret);
> if (ret == -EPROBE_DEFER)
> goto err_alloc;
>
> dev_err(&pdev->dev, "unable to request PWM, trying legacy API\n");
> pb->legacy = true;
> pb->pwm = pwm_request(data->pwm_id, "pwm-backlight");
>
> Could you either revert 68feaca0b13e or find a better solution to repair the
> legacy platorms please ?
Ok, no answer, so I'll post the revert.
Cheers.
--
Robert
More information about the linux-arm-kernel
mailing list