Re: [PATCH v3 3/3] ARM: dts: use syscon in cygnus touchscreen dt node

From: Raveendra Padasalagi
Date: Mon Feb 22 2016 - 03:10:13 EST


On Mon, Feb 22, 2016 at 1:19 PM, Raveendra Padasalagi
<raveendra.padasalagi@xxxxxxxxxxxx> wrote:
> In Cygnus SOC touch screen controller registers are shared
> with ADC and flex timer. Using readl/writel could lead to
> race condition. So in such case register access is handled
> through syscon framework API's in the touch screen driver.
> This feature is enabled if "brcm,iproc-touchscreen-syscon"
> compatible string is selected in touchscreen dt node.
>
> So this patch enables syscon support in touchscreen driver
> by adding necessary properties in touchscreen dt node.
>
> Signed-off-by: Raveendra Padasalagi <raveendra.padasalagi@xxxxxxxxxxxx>
> Reviewed-by: Ray Jui <ray.jui@xxxxxxxxxxxx>
> Reviewed-by: Scott Branden <scott.branden@xxxxxxxxxxxx>
> ---
> arch/arm/boot/dts/bcm-cygnus.dtsi | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm/boot/dts/bcm-cygnus.dtsi b/arch/arm/boot/dts/bcm-cygnus.dtsi
> index 3878793..1704dc0 100644
> --- a/arch/arm/boot/dts/bcm-cygnus.dtsi
> +++ b/arch/arm/boot/dts/bcm-cygnus.dtsi
> @@ -351,9 +351,16 @@
> <&pinctrl 142 10 1>;
> };
>
> + ts_adc_syscon: ts_adc_syscon@180a6000 {
> + compatible = "brcm,iproc-ts-adc-syscon","syscon";
> + reg = <0x180a6000 0xc30>;
> + };
> +
> touchscreen: tsc@180a6000 {
> - compatible = "brcm,iproc-touchscreen";
> - reg = <0x180a6000 0x40>;
> + compatible = "brcm,iproc-touchscreen-syscon";

Hi Rob,
In patchset V2 you had a comment as to have only "syscon" support,
Since having "syscon" only support breaks the dt backward compatibility
as the existing driver has support for "reg". So in patchset V3 I have
not addressed this comment yet. Waiting for your opinion on whether
to proceed with "syscon" only support.

-Raveendra
> + #address-cells = <1>;
> + #size-cells = <1>;
> + ts_syscon = <&ts_adc_syscon>;
> clocks = <&asiu_clks BCM_CYGNUS_ASIU_ADC_CLK>;
> clock-names = "tsc_clk";
> interrupts = <GIC_SPI 164 IRQ_TYPE_LEVEL_HIGH>;
> --
> 1.9.1
>