Subject: [PATCH 4/6] Staging/iio/adc/touchscreen/MXS: add i.MX23 support to the LRADC touchscreen driver

From: [email-masked] (Jonathan Cameron)
Date: Sun, 15 Sep 2013 11:50:09 +0100

On 09/11/13 09:18, Juergen Beisert wrote:
> Distinguish i.MX23 and i.MX28 at runtime and do the same for both SoC at least
> for the 4 wire touchscreen.
> 
> Note: support for the remaining LRADC channels is not tested on an
> i.MX23 yet.
An ominous comment. Are you likely to test them soon?

Minor code layout comment inline but otherwise I'm just looking for an
ack from Marek.
> 
> Signed-off-by: Juergen Beisert <[email-masked]>
> CC: linux-arm-kernel at lists.infradead.org
> CC: devel at driverdev.osuosl.org
> CC: Marek Vasut <[email-masked]>
> CC: Fabio Estevam <[email-masked]>
> CC: Jonathan Cameron <[email-masked]>
> ---
>  drivers/staging/iio/adc/mxs-lradc.c | 45 +++++++++++++++++++++++++++++++++----
>  1 file changed, 41 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/staging/iio/adc/mxs-lradc.c b/drivers/staging/iio/adc/mxs-lradc.c
> index 4317fee..c81b186 100644
> --- a/drivers/staging/iio/adc/mxs-lradc.c
> +++ b/drivers/staging/iio/adc/mxs-lradc.c
> @@ -188,20 +188,33 @@ struct mxs_lradc {
>  # define LRADC_CTRL0_MX28_XNPSW	/* XM */	(1 << 17)
>  # define LRADC_CTRL0_MX28_XPPSW	/* XP */	(1 << 16)
>  
> +# define LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE	(1 << 20)
> +# define LRADC_CTRL0_MX23_YM			(1 << 19)
> +# define LRADC_CTRL0_MX23_XM			(1 << 18)
> +# define LRADC_CTRL0_MX23_YP			(1 << 17)
> +# define LRADC_CTRL0_MX23_XP			(1 << 16)
> +
>  # define LRADC_CTRL0_MX28_PLATE_MASK \
>  		(LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE | \
>  		LRADC_CTRL0_MX28_YNNSW | LRADC_CTRL0_MX28_YPNSW | \
>  		LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW | \
>  		LRADC_CTRL0_MX28_XNPSW | LRADC_CTRL0_MX28_XPPSW)
>  
> +# define LRADC_CTRL0_MX23_PLATE_MASK \
> +		(LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE | \
> +		LRADC_CTRL0_MX23_YM | LRADC_CTRL0_MX23_XM | \
> +		LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_XP)
> +
>  #define	LRADC_CTRL1				0x10
>  #define	LRADC_CTRL1_TOUCH_DETECT_IRQ_EN		(1 << 24)
>  #define	LRADC_CTRL1_LRADC_IRQ_EN(n)		(1 << ((n) + 16))
>  #define	LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK	(0x1fff << 16)
> +#define	LRADC_CTRL1_MX23_LRADC_IRQ_EN_MASK	(0x01ff << 16)
>  #define	LRADC_CTRL1_LRADC_IRQ_EN_OFFSET		16
>  #define	LRADC_CTRL1_TOUCH_DETECT_IRQ		(1 << 8)
>  #define	LRADC_CTRL1_LRADC_IRQ(n)		(1 << (n))
>  #define	LRADC_CTRL1_MX28_LRADC_IRQ_MASK		0x1fff
> +#define	LRADC_CTRL1_MX23_LRADC_IRQ_MASK		0x01ff
>  #define	LRADC_CTRL1_LRADC_IRQ_OFFSET		0
>  
>  #define	LRADC_CTRL2				0x20
> @@ -252,36 +265,50 @@ static void mxs_lradc_reg(struct mxs_lradc *lradc, u32 val, u32 reg)
>  
>  static u32 mxs_lradc_plate_mask(struct mxs_lradc *lradc)
>  {
> +	if (lradc->soc == IMX23_LRADC)
> +		return LRADC_CTRL0_MX23_PLATE_MASK;
>  	return LRADC_CTRL0_MX28_PLATE_MASK;
>  }
>  
>  static u32 mxs_lradc_irq_en_mask(struct mxs_lradc *lradc)
>  {
> +	if (lradc->soc == IMX23_LRADC)
> +		return LRADC_CTRL1_MX23_LRADC_IRQ_EN_MASK;
>  	return LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK;
>  }
>  
>  static u32 mxs_lradc_irq_mask(struct mxs_lradc *lradc)
>  {
> +	if (lradc->soc == IMX23_LRADC)
> +		return LRADC_CTRL1_MX23_LRADC_IRQ_MASK;
>  	return LRADC_CTRL1_MX28_LRADC_IRQ_MASK;
>  }
>  
>  static u32 mxs_lradc_touch_detect_bit(struct mxs_lradc *lradc)
>  {
> +	if (lradc->soc == IMX23_LRADC)
> +		return LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE;
>  	return LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE;
>  }
>  
>  static u32 mxs_lradc_drive_x_plate(struct mxs_lradc *lradc)
>  {
> +	if (lradc->soc == IMX23_LRADC)
> +		return LRADC_CTRL0_MX23_XP | LRADC_CTRL0_MX23_XM;
>  	return LRADC_CTRL0_MX28_XPPSW | LRADC_CTRL0_MX28_XNNSW;
>  }
>  
>  static u32 mxs_lradc_drive_y_plate(struct mxs_lradc *lradc)
>  {
> +	if (lradc->soc == IMX23_LRADC)
> +		return LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_YM;
>  	return LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_YNNSW;
>  }
>  
>  static u32 mxs_lradc_drive_pressure(struct mxs_lradc *lradc)
>  {
> +	if (lradc->soc == IMX23_LRADC)
> +		return LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_XM;
>  	return LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW;
Whilst it obviously doesn't actually matter, having an else
in there would make the code more consistent so personally
I would prefer it to be there.

>  }
>  
> @@ -319,7 +346,8 @@ static int mxs_lradc_read_raw(struct iio_dev *iio_dev,
>  	 * Virtual channel 0 is always used here as the others are always not
>  	 * used if doing raw sampling.
>  	 */
> -	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK,
> +	if (lradc->soc == IMX28_LRADC)
> +		mxs_lradc_reg_clear(lradc, LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK,
>  			LRADC_CTRL1);
>  	mxs_lradc_reg_clear(lradc, 0xff, LRADC_CTRL0);
>  
> @@ -767,7 +795,8 @@ static int mxs_lradc_buffer_preenable(struct iio_dev *iio)
>  	if (ret < 0)
>  		goto err_buf;
>  
> -	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK,
> +	if (lradc->soc == IMX28_LRADC)
> +		mxs_lradc_reg_clear(lradc, LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK,
>  							LRADC_CTRL1);
>  	mxs_lradc_reg_clear(lradc, 0xff, LRADC_CTRL0);
>  
> @@ -805,7 +834,8 @@ static int mxs_lradc_buffer_postdisable(struct iio_dev *iio)
>  					LRADC_DELAY_KICK, LRADC_DELAY(0));
>  
>  	mxs_lradc_reg_clear(lradc, 0xff, LRADC_CTRL0);
> -	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK,
> +	if (lradc->soc == IMX28_LRADC)
> +		mxs_lradc_reg_clear(lradc, LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK,
>  					LRADC_CTRL1);
>  
>  	kfree(lradc->buffer);
> @@ -909,7 +939,8 @@ static int mxs_lradc_hw_init(struct mxs_lradc *lradc)
>  	mxs_lradc_reg(lradc, 0, LRADC_DELAY(3));
>  
>  	/* Configure the touchscreen type */
> -	mxs_lradc_reg_clear(lradc, LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,
> +	if (lradc->soc == IMX28_LRADC) {
> +		mxs_lradc_reg_clear(lradc, LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,
>  							LRADC_CTRL0);
>  
>  	if (lradc->use_touchscreen == MXS_LRADC_TOUCHSCREEN_5WIRE)
> @@ -987,6 +1018,12 @@ static int mxs_lradc_probe(struct platform_device *pdev)
>  		dev_warn(dev, "Unsupported number of touchscreen wires (%d)\n",
>  				ts_wires);
>  
> +	if ((lradc->soc == IMX23_LRADC) && (ts_wires == 5)) {
> +		dev_warn(dev, "No support for 5 wire touches on i.MX23\n");
> +		dev_warn(dev, "Falling back to 4 wire\n");
> +		ts_wires = 4;
> +	}
> +
>  	/* Grab all IRQ sources */
>  	for (i = 0; i < of_cfg->irq_count; i++) {
>  		lradc->irq[i] = platform_get_irq(pdev, i);
>