Re: [PATCH v2 2/3] Input: ti_am335x_tsc: Add support for ti,charge-delay-ns

[Dmitry Torokhov]

On Fri, Nov 11, 2016 at 01:28:19PM +0530, Mugunthan V N wrote:
> ti,charge-delay will be deprecated as it represents number of
> clock cycles and the DT entries are done in assumption of 3MHz
> TSCADC clock, but clock can be set upto 24MHz. So driver add
> support for ti,charge-delay-ns and do not drop support for
> ti,charge-delay to support old dtbs and it will be assumed that
> it is for 3MHz TSCADC clock and will be calculated as per current
> clock speed.
> 
> Signed-off-by: Mugunthan V N <mugunthanvnm@xxxxxx>

Acked-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>

> ---
>  drivers/input/touchscreen/ti_am335x_tsc.c | 31 +++++++++++++++++++++++--------
>  1 file changed, 23 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/input/touchscreen/ti_am335x_tsc.c b/drivers/input/touchscreen/ti_am335x_tsc.c
> index 7953381d939a..104b3640f728 100644
> --- a/drivers/input/touchscreen/ti_am335x_tsc.c
> +++ b/drivers/input/touchscreen/ti_am335x_tsc.c
> @@ -379,15 +379,30 @@ static int titsc_parse_dt(struct platform_device *pdev,
>  		ts_dev->coordinate_readouts = 5;
>  	}
>  
> -	err = of_property_read_u32(node, "ti,charge-delay",
> +	err = of_property_read_u32(node, "ti,charge-delay-ns",
>  				   &ts_dev->charge_delay);
> -	/*
> -	 * If ti,charge-delay value is not specified, then use
> -	 * CHARGEDLY_OPENDLY as the default value.
> -	 */
> -	if (err < 0) {
> -		ts_dev->charge_delay = CHARGEDLY_OPENDLY;
> -		dev_warn(&pdev->dev, "ti,charge-delay not specified\n");
> +	if (err >= 0) {
> +		u64 charge_delay = ts_dev->charge_delay;
> +
> +		charge_delay *= ADC_CLK;
> +		do_div(charge_delay, 1E9);
> +		ts_dev->charge_delay = (u32)charge_delay;
> +	} else {
> +		err = of_property_read_u32(node, "ti,charge-delay",
> +					   &ts_dev->charge_delay);
> +		/*
> +		 * If ti,charge-delay value is not specified, then use
> +		 * CHARGEDLY_OPENDLY as the default value.
> +		 */
> +		if (err < 0) {
> +			ts_dev->charge_delay = CHARGEDLY_OPENDLY;
> +			dev_warn(&pdev->dev, "ti,charge-delay not specified\n");
> +		}
> +		/*
> +		 * ti,charge-delay is specified with referrence to 3MHz,
> +		 * so convert it to in referrence to current clock
> +		 */
> +		ts_dev->charge_delay *= ADC_CLK / 3000000;
>  	}
>  
>  	return of_property_read_u32_array(node, "ti,wire-config",
> -- 
> 2.11.0.rc0.7.gbe5a750
> 

-- 
Dmitry