[Letux-kernel] [PATCH] ARM: dts: am33xx-l4: Add missing touchscreen clock properties

H. Nikolaus Schaller hns at goldelico.com
Mon Mar 7 20:19:48 CET 2022


Hi Miquel,
some tiny typos...

> Am 07.03.2022 um 12:14 schrieb Miquel Raynal <miquel.raynal at bootlin.com>:
> 
> When adding support for TI magadc, the MFD driver (common to the

"magadc"?

> touchscreen and the ADC) got updated to ease the insertion of a new DT
> node for the ADC, with its own compatible, clocks, etc. Commit
> 235a96e92c16 ("mfd: ti_am335x_tscadc: Don't search the tree for our
> clock") removed one compatible specific information which was the clock
> name, because the clock was looked up from scratch in the DT while this
> hardware block was only fed by a single clock, already defined and
> properly filled in the DT.
> 
> Problem is, this change was only validated with an am437x-based board,
> where the clocks are effectively correctly defined and referenced. But
> on am33xx, the ADC clock is also correctly defined but is not referenced
> with a clock phandle as it out to be.

maybe you mean "ought to be"?

> 
> The touchscreen bindings clearly state that the clocks/clock-names
> properties are mandatory, but they have been forgotten in one DTSI. This
> was probably not noticed in the first place because of the clock
> actually existing and the clk_get() call going through all the tree
> anyway.
> 
> Add the missing clock phandles in the am33xx touchscreen description.

Yes, makes touch on BeagleBoard Black with Chipsee 4"3 panel work again!

> 
> Reported-by: H. Nikolaus Schaller <hns at goldelico.com>
> Fixes: 235a96e92c16 ("mfd: ti_am335x_tscadc: Don't search the tree for our clock")
Tested-by: H. Nikolaus Schaller <hns at goldelico.com>
> 
> Signed-off-by: Miquel Raynal <miquel.raynal at bootlin.com>
> ---
> 
> Hello Nikolaus, as I told you I don't have the relevant hardware to
> verify that this actually fixes your situation but I am rather
> confident. Could you please give this a try?
> Thanks! Miquel

> 
> arch/arm/boot/dts/am33xx-l4.dtsi | 2 ++
> 1 file changed, 2 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/am33xx-l4.dtsi b/arch/arm/boot/dts/am33xx-l4.dtsi
> index c9629cb5ccd1..7da42a5b959c 100644
> --- a/arch/arm/boot/dts/am33xx-l4.dtsi
> +++ b/arch/arm/boot/dts/am33xx-l4.dtsi
> @@ -263,6 +263,8 @@ tscadc: tscadc at 0 {
> 				compatible = "ti,am3359-tscadc";
> 				reg = <0x0 0x1000>;
> 				interrupts = <16>;
> +				clocks = <&adc_tsc_fck>;
> +				clock-names = "fck";
> 				status = "disabled";
> 				dmas = <&edma 53 0>, <&edma 57 0>;
> 				dma-names = "fifo0", "fifo1";
> -- 
> 2.27.0
> 

BR and thanks,
Nikolaus




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