Re: [PATCH 25/40] mfd: ti_am335x_tscadc: Add a boolean to clarify the presence of a touchscreen

[Jonathan Cameron <jic23@kernel.org>]

On Wed, 25 Aug 2021 17:25:03 +0200
Miquel Raynal <miquel.raynal@bootlin.com> wrote:

> Just checking the number of wires will soon not be enough, add a boolean
> to indicated the actual use or not of the touchscreen.
> 
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
> ---
>  drivers/mfd/ti_am335x_tscadc.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335x_tscadc.c
> index 2f934fd2154a..30f53cdb41f8 100644
> --- a/drivers/mfd/ti_am335x_tscadc.c
> +++ b/drivers/mfd/ti_am335x_tscadc.c
> @@ -121,6 +121,7 @@ static	int ti_tscadc_probe(struct platform_device *pdev)
>  	const __be32 *cur;
>  	struct clk *clk;
>  	u32 val;
> +	bool use_tsc = false;
>  	int tscmag_wires = 0, adc_channels = 0, readouts = 0, cell_idx = 0;
>  	int total_channels, err;
>  
> @@ -141,6 +142,8 @@ static	int ti_tscadc_probe(struct platform_device *pdev)
>  	node = of_get_child_by_name(pdev->dev.of_node, "tsc");
>  	of_property_read_u32(node, "ti,wires", &tscmag_wires);
>  	of_property_read_u32(node, "ti,coordiante-readouts", &readouts);
> +	if (tscmag_wires)
> +		use_tsc = true;
>  
>  	node = of_get_child_by_name(pdev->dev.of_node, "adc");
>  	of_property_for_each_u32(node, "ti,adc-channels", prop, cur, val) {
> @@ -163,7 +166,7 @@ static	int ti_tscadc_probe(struct platform_device *pdev)
>  		return -EINVAL;
>  	}
>  
> -	if (readouts * 2 + 2 + adc_channels > 16) {
> +	if (use_tsc && (readouts * 2 + 2 + adc_channels > 16)) {

This one is adding a check that wasn't there before.  The description should
mention why it will now be necessary and isn't a bug...

>  		dev_err(&pdev->dev, "Too many step configurations requested\n");
>  		return -EINVAL;
>  	}
> @@ -218,7 +221,7 @@ static	int ti_tscadc_probe(struct platform_device *pdev)
>  	tscadc->ctrl = CNTRLREG_TSC_STEPCONFIGWRT | CNTRLREG_STEPID;
>  	regmap_write(tscadc->regmap, REG_CTRL, tscadc->ctrl);
>  
> -	if (tscmag_wires > 0) {
> +	if (use_tsc) {
>  		tscadc->ctrl |= CNTRLREG_TSC_ENB;
>  		if (tscmag_wires == 5)
>  			tscadc->ctrl |= CNTRLREG_TSC_5WIRE;