[PATCH 7/9] drm/simplekms: Acquire regulators from DT device node

[Geert Uytterhoeven]

Hi Thomas,

On Thu, Jun 25, 2020 at 2:00 PM Thomas Zimmermann <tzimmermann at suse.de> wrote:
> Make sure required hardware regulators are enabled while the firmware
> framebuffer is in use.
>
> The basic code has been taken from the simplefb driver and adapted
> to DRM. Regulators are released automatically via devres helpers.
>
> Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>

Thanks for your patch!

> --- a/drivers/gpu/drm/tiny/simplekms.c
> +++ b/drivers/gpu/drm/tiny/simplekms.c
> @@ -4,6 +4,7 @@
>  #include <linux/of_clk.h>
>  #include <linux/platform_data/simplefb.h>
>  #include <linux/platform_device.h>
> +#include <linux/regulator/consumer.h>
>
>  #include <drm/drm_atomic_state_helper.h>
>  #include <drm/drm_connector.h>
> @@ -198,6 +199,11 @@ struct simplekms_device {
>         unsigned int clk_count;
>         struct clk **clks;
>  #endif
> +       /* regulators */
> +#if defined CONFIG_OF && defined CONFIG_REGULATOR
> +       unsigned int regulator_count;
> +       struct regulator **regulators;
> +#endif
>
>         /* simplefb settings */
>         struct drm_display_mode mode;
> @@ -315,6 +321,125 @@ static int simplekms_device_init_clocks(struct simplekms_device *sdev)
>  }
>  #endif
>
> +#if defined CONFIG_OF && defined CONFIG_REGULATOR
> +
> +#define SUPPLY_SUFFIX "-supply"
> +
> +/*
> + * Regulator handling code.
> + *
> + * Here we handle the num-supplies and vin*-supply properties of our
> + * "simple-framebuffer" dt node. This is necessary so that we can make sure
> + * that any regulators needed by the display hardware that the bootloader
> + * set up for us (and for which it provided a simplefb dt node), stay up,
> + * for the life of the simplefb driver.

Looks like there's a bulk regulator API, too?

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds