Re: [PATCH 2/4] ARM: dts: omap: omap4-epson-embt2ws: wire up regulators

From: Andreas Kemnade
Date: Fri Oct 04 2024 - 05:01:30 EST


Am Fri, 4 Oct 2024 10:38:22 +0300
schrieb Roger Quadros <rogerq@xxxxxxxxxx>:

> On 01/10/2024 00:30, Andreas Kemnade wrote:
> > Wire up the regulators where usage is plausible. Do not
> > wire them if purpose/usage is unclear like 5V for
> > many things requiring lower voltages.
> >
> > Signed-off-by: Andreas Kemnade <andreas@xxxxxxxxxxxx>
> > ---
> > arch/arm/boot/dts/ti/omap/omap4-epson-embt2ws.dts | 11 ++++-------
> > 1 file changed, 4 insertions(+), 7 deletions(-)
> >
> > diff --git a/arch/arm/boot/dts/ti/omap/omap4-epson-embt2ws.dts
> > b/arch/arm/boot/dts/ti/omap/omap4-epson-embt2ws.dts index
> > d6b0abba19f6..cc1b6080bf95 100644 ---
> > a/arch/arm/boot/dts/ti/omap/omap4-epson-embt2ws.dts +++
> > b/arch/arm/boot/dts/ti/omap/omap4-epson-embt2ws.dts @@ -20,13
> > +20,13 @@ memory@80000000 { backlight-left {
> > compatible = "pwm-backlight";
> > pwms = <&twl_pwm 1 7812500>;
> > - power-supply = <&unknown_supply>;
> > + power-supply = <&lb_v50>;
>
> This is probably wrong. I noticed this while reviewing patch 3.
>
> you probably want to wire this to blc_l?
>
No idea was blc_l is. I did not find any code handling blc_l.
looking at the vendor kernel:

$ grep -R BLC_L_GPIO *
arch/arm/mach-omap2/board-bt2ws.c:#define BLC_L_GPIO
16 /* LB LED GPIO */ arch/arm/mach-omap2/board-bt2ws.c:
{BLC_L_GPIO, GPIOF_OUT_INIT_LOW, "gpio_blc_l" },
arch/arm/mach-omap2/board-bt2ws.c: gpio_export(BLC_L_GPIO, 0);
arch/arm/mach-omap2/board-bt2ts.c:#define BLC_L_GPIO
16 /* LB LED GPIO */ arch/arm/mach-omap2/board-bt2ts.c:
{BLC_L_GPIO, GPIOF_OUT_INIT_LOW, "gpio_blc_l" },
arch/arm/mach-omap2/board-bt2ts.c: gpio_export(BLC_L_GPIO, 0);

These two gpios are exported. But they seem not to influence
backlight in any way. I just tested again to make sure. Maybe it is just
a leftover from earlier board revisions.

> > };
> >
> > backlight-right {
> > compatible = "pwm-backlight";
> > pwms = <&twl_pwm 0 7812500>;
> > - power-supply = <&unknown_supply>;
> > + power-supply = <&lb_v50>;
>
> this one should be wired to blc_r?
>
Same as with blc_l.
$ grep -R BLC_R_GPIO *
arch/arm/mach-omap2/board-bt2ws.c:#define BLC_R_GPIO
17 /* LB LED GPIO */ arch/arm/mach-omap2/board-bt2ws.c:
{BLC_R_GPIO, GPIOF_OUT_INIT_LOW, "gpio_blc_r" },
arch/arm/mach-omap2/board-bt2ws.c: gpio_export(BLC_R_GPIO, 0);
arch/arm/mach-omap2/board-bt2ts.c:#define BLC_R_GPIO
17 /* LB LED GPIO */ arch/arm/mach-omap2/board-bt2ts.c:
{BLC_R_GPIO, GPIOF_OUT_INIT_LOW, "gpio_blc_r" },
arch/arm/mach-omap2/board-bt2ts.c: gpio_export(BLC_R_GPIO, 0);

Regards,
Andreas