[resend][PATCH v3 6/6] iio: at91: introduce touch screen support in iio adc driver

Josh Wu josh.wu at atmel.com
Fri Sep 13 05:32:21 EDT 2013


Dear Dmitry Torokhov

Could you have any comments for this patch?

Best Regards,
Josh Wu

On 8/28/2013 3:45 PM, Josh Wu wrote:
> AT91 ADC hardware integrate touch screen support. So this patch add touch
> screen support for at91 adc iio driver.
> To enable touch screen support in adc, you need to add the dt parameters:
>    1. which type of touch are used? (4 or 5 wires), sample period time.
>    2. correct pressure detect threshold value.
>
> In the meantime, since touch screen will use a interal period trigger of adc,
> so it is conflict to other hardware triggers. Driver will disable the hardware
> trigger support if touch screen is enabled.
>
> This driver has been tested in AT91SAM9X5-EK and SAMA5D3x-EK.
>
> Signed-off-by: Josh Wu <josh.wu at atmel.com>
> Cc: Dmitry Torokhov <dmitry.torokhov at gmail.com>
> CC: devicetree at vger.kernel.org
> ---
> resend v3:
>    Since [v3 5/6] is resended for compiling error fix. So rebase this patch
>
> v2 --> v3:
>    1. fix according to Dmitry's suggestion.
>
> v1 --> v2:
>    1. use the multiple compatible string for different IPs.
>    2. hide the driver configuration in driver code instead of exposing them in dt.
>       Such like sample period, pen detect debounce time and etc.
>    3. add a new dt parameter: ts-pressure-threshold. this value is much related
>       with different chips and boards.
>
>   .../devicetree/bindings/arm/atmel-adc.txt          |    7 +
>   arch/arm/mach-at91/include/mach/at91_adc.h         |   34 ++
>   drivers/iio/adc/at91_adc.c                         |  388 ++++++++++++++++++--
>   3 files changed, 405 insertions(+), 24 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/arm/atmel-adc.txt b/Documentation/devicetree/bindings/arm/atmel-adc.txt
> index 0e65e01..d106146 100644
> --- a/Documentation/devicetree/bindings/arm/atmel-adc.txt
> +++ b/Documentation/devicetree/bindings/arm/atmel-adc.txt
> @@ -23,6 +23,13 @@ Optional properties:
>   		       resolution will be used.
>     - atmel,adc-sleep-mode: Boolean to enable sleep mode when no conversion
>     - atmel,adc-sample-hold-time: Sample and Hold Time in microseconds
> +  - atmel,adc-ts-wires: Number of touch screen wires. Should be 4 or 5. If this
> +                        value is set, then adc driver will enable touch screen
> +                        support.
> +    NOTE: when adc touch screen enabled, the adc hardware trigger will be
> +          disabled. Since touch screen will occupied the trigger register.
> +  - atmel,adc-ts-pressure-threshold: a pressure threshold for touchscreen. It
> +                                     make touch detect more precision.
>    
>   Optional trigger Nodes:
>     - Required properties:
> diff --git a/arch/arm/mach-at91/include/mach/at91_adc.h b/arch/arm/mach-at91/include/mach/at91_adc.h
> index 048a57f..c287307 100644
> --- a/arch/arm/mach-at91/include/mach/at91_adc.h
> +++ b/arch/arm/mach-at91/include/mach/at91_adc.h
> @@ -60,14 +60,48 @@
>   #define AT91_ADC_IER		0x24		/* Interrupt Enable Register */
>   #define AT91_ADC_IDR		0x28		/* Interrupt Disable Register */
>   #define AT91_ADC_IMR		0x2C		/* Interrupt Mask Register */
> +#define		AT91_ADC_IER_PEN	(1 << 29)
> +#define		AT91_ADC_IER_NOPEN	(1 << 30)
> +#define		AT91_ADC_IER_XRDY	(1 << 20)
> +#define		AT91_ADC_IER_YRDY	(1 << 21)
> +#define		AT91_ADC_IER_PRDY	(1 << 22)
> +#define		AT91_ADC_ISR_PENS	(1 << 31)
>   
>   #define AT91_ADC_CHR(n)		(0x30 + ((n) * 4))	/* Channel Data Register N */
>   #define		AT91_ADC_DATA		(0x3ff)
>   
>   #define AT91_ADC_CDR0_9X5	(0x50)			/* Channel Data Register 0 for 9X5 */
>   
> +#define AT91_ADC_ACR		0x94	/* Analog Control Register */
> +#define		AT91_ADC_ACR_PENDETSENS	(0x3 << 0)	/* pull-up resistor */
> +
> +#define AT91_ADC_TSMR		0xB0
> +#define		AT91_ADC_TSMR_TSMODE	(3 << 0)	/* Touch Screen Mode */
> +#define			AT91_ADC_TSMR_TSMODE_NONE		(0 << 0)
> +#define			AT91_ADC_TSMR_TSMODE_4WIRE_NO_PRESS	(1 << 0)
> +#define			AT91_ADC_TSMR_TSMODE_4WIRE_PRESS	(2 << 0)
> +#define			AT91_ADC_TSMR_TSMODE_5WIRE		(3 << 0)
> +#define		AT91_ADC_TSMR_TSAV	(3 << 4)	/* Averages samples */
> +#define			AT91_ADC_TSMR_TSAV_(x)		((x) << 4)
> +#define		AT91_ADC_TSMR_SCTIM	(0x0f << 16)	/* Switch closure time */
> +#define		AT91_ADC_TSMR_PENDBC	(0x0f << 28)	/* Pen Debounce time */
> +#define			AT91_ADC_TSMR_PENDBC_(x)	((x) << 28)
> +#define		AT91_ADC_TSMR_NOTSDMA	(1 << 22)	/* No Touchscreen DMA */
> +#define		AT91_ADC_TSMR_PENDET_DIS	(0 << 24)	/* Pen contact detection disable */
> +#define		AT91_ADC_TSMR_PENDET_ENA	(1 << 24)	/* Pen contact detection enable */
> +
> +#define AT91_ADC_TSXPOSR	0xB4
> +#define AT91_ADC_TSYPOSR	0xB8
> +#define AT91_ADC_TSPRESSR	0xBC
> +
>   #define AT91_ADC_TRGR_9260	AT91_ADC_MR
>   #define AT91_ADC_TRGR_9G45	0x08
>   #define AT91_ADC_TRGR_9X5	0xC0
>   
> +/* Trigger Register bit field */
> +#define		AT91_ADC_TRGR_TRGPER	(0xffff << 16)
> +#define			AT91_ADC_TRGR_TRGPER_(x)	((x) << 16)
> +#define		AT91_ADC_TRGR_TRGMOD	(0x7 << 0)
> +#define			AT91_ADC_TRGR_MOD_PERIOD_TRIG	(5 << 0)
> +
>   #endif
> diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
> index 0f4621a..beec9ae 100644
> --- a/drivers/iio/adc/at91_adc.c
> +++ b/drivers/iio/adc/at91_adc.c
> @@ -11,6 +11,7 @@
>   #include <linux/clk.h>
>   #include <linux/err.h>
>   #include <linux/io.h>
> +#include <linux/input.h>
>   #include <linux/interrupt.h>
>   #include <linux/jiffies.h>
>   #include <linux/kernel.h>
> @@ -39,7 +40,23 @@
>   #define at91_adc_writel(st, reg, val) \
>   	(writel_relaxed(val, st->reg_base + reg))
>   
> +#define DRIVER_NAME		"at91_adc"
> +#define MAX_POS_BITS		12
> +
> +#define TOUCH_SAMPLE_PERIOD_US		2000	/* 2ms */
> +#define TOUCH_PEN_DETECT_DEBOUNCE_US	200
> +
>   struct at91_adc_caps {
> +	bool	has_ts;		/* Support touch screen */
> +	bool	has_tsmr;	/* only at91sam9x5, sama5d3 have TSMR reg */
> +	/*
> +	 * Numbers of sampling data will be averaged. Can be 0~3.
> +	 * Hardware can average (2 ^ ts_filter_average) sample data.
> +	 */
> +	u8	ts_filter_average;
> +	/* Pen Detection input pull-up resistor, can be 0~3 */
> +	u8	ts_pen_detect_sensitivity;
> +
>   	/* startup time calculate function */
>   	u32 (*calc_startup_ticks)(u8 startup_time, u32 adc_clk_khz);
>   
> @@ -47,6 +64,12 @@ struct at91_adc_caps {
>   	struct at91_adc_reg_desc registers;
>   };
>   
> +enum atmel_adc_ts_type {
> +	ATMEL_ADC_TOUCHSCREEN_NONE = 0,
> +	ATMEL_ADC_TOUCHSCREEN_4WIRE = 4,
> +	ATMEL_ADC_TOUCHSCREEN_5WIRE = 5,
> +};
> +
>   struct at91_adc_state {
>   	struct clk		*adc_clk;
>   	u16			*buffer;
> @@ -71,6 +94,26 @@ struct at91_adc_state {
>   	bool			low_res;	/* the resolution corresponds to the lowest one */
>   	wait_queue_head_t	wq_data_avail;
>   	struct at91_adc_caps	*caps;
> +
> +	/*
> +	 * Following ADC channels are shared by touchscreen:
> +	 *
> +	 * CH0 -- Touch screen XP/UL
> +	 * CH1 -- Touch screen XM/UR
> +	 * CH2 -- Touch screen YP/LL
> +	 * CH3 -- Touch screen YM/Sense
> +	 * CH4 -- Touch screen LR(5-wire only)
> +	 *
> +	 * The bitfields below represents the reserved channel in the
> +	 * touchscreen mode.
> +	 */
> +#define CHAN_MASK_TOUCHSCREEN_4WIRE	(0xf << 0)
> +#define CHAN_MASK_TOUCHSCREEN_5WIRE	(0x1f << 0)
> +	enum atmel_adc_ts_type	touchscreen_type;
> +	struct input_dev	*ts_input;
> +
> +	u16			ts_sample_period_val;
> +	u32			ts_pressure_threshold;
>   };
>   
>   static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
> @@ -105,14 +148,10 @@ static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
>   	return IRQ_HANDLED;
>   }
>   
> -static irqreturn_t at91_adc_eoc_trigger(int irq, void *private)
> +/* Handler for classic adc channel eoc trigger */
> +void handle_adc_eoc_trigger(int irq, struct iio_dev *idev)
>   {
> -	struct iio_dev *idev = private;
>   	struct at91_adc_state *st = iio_priv(idev);
> -	u32 status = at91_adc_readl(st, st->registers->status_register);
> -
> -	if (!(status & st->registers->drdy_mask))
> -		return IRQ_HANDLED;
>   
>   	if (iio_buffer_enabled(idev)) {
>   		disable_irq_nosync(irq);
> @@ -122,6 +161,115 @@ static irqreturn_t at91_adc_eoc_trigger(int irq, void *private)
>   		st->done = true;
>   		wake_up_interruptible(&st->wq_data_avail);
>   	}
> +}
> +
> +static int at91_ts_sample(struct at91_adc_state *st)
> +{
> +	unsigned int xscale, yscale, reg, z1, z2;
> +	unsigned int x, y, pres, xpos, ypos;
> +	unsigned int rxp = 1;
> +	unsigned int factor = 1000;
> +	struct iio_dev *idev = iio_priv_to_dev(st);
> +
> +	unsigned int xyz_mask_bits = st->res;
> +	unsigned int xyz_mask = (1 << xyz_mask_bits) - 1;
> +
> +	/* calculate position */
> +	/* x position = (x / xscale) * max, max = 2^MAX_POS_BITS - 1 */
> +	reg = at91_adc_readl(st, AT91_ADC_TSXPOSR);
> +	xpos = reg & xyz_mask;
> +	x = (xpos << MAX_POS_BITS) - xpos;
> +	xscale = (reg >> 16) & xyz_mask;
> +	if (xscale == 0) {
> +		dev_err(&idev->dev, "Error: xscale == 0!\n");
> +		return -1;
> +	}
> +	x /= xscale;
> +
> +	/* y position = (y / yscale) * max, max = 2^MAX_POS_BITS - 1 */
> +	reg = at91_adc_readl(st, AT91_ADC_TSYPOSR);
> +	ypos = reg & xyz_mask;
> +	y = (ypos << MAX_POS_BITS) - ypos;
> +	yscale = (reg >> 16) & xyz_mask;
> +	if (yscale == 0) {
> +		dev_err(&idev->dev, "Error: yscale == 0!\n");
> +		return -1;
> +	}
> +	y /= yscale;
> +
> +	/* calculate the pressure */
> +	reg = at91_adc_readl(st, AT91_ADC_TSPRESSR);
> +	z1 = reg & xyz_mask;
> +	z2 = (reg >> 16) & xyz_mask;
> +
> +	if (z1 != 0)
> +		pres = rxp * (x * factor / 1024) * (z2 * factor / z1 - factor)
> +			/ factor;
> +	else
> +		pres = st->ts_pressure_threshold;	/* no pen contacted */
> +
> +	dev_dbg(&idev->dev, "xpos = %d, xscale = %d, ypos = %d, yscale = %d, z1 = %d, z2 = %d, press = %d\n",
> +				xpos, xscale, ypos, yscale, z1, z2, pres);
> +
> +	if (pres < st->ts_pressure_threshold) {
> +		dev_dbg(&idev->dev, "x = %d, y = %d, pressure = %d\n",
> +					x, y, pres / factor);
> +		input_report_abs(st->ts_input, ABS_X, x);
> +		input_report_abs(st->ts_input, ABS_Y, y);
> +		input_report_abs(st->ts_input, ABS_PRESSURE, pres);
> +		input_report_key(st->ts_input, BTN_TOUCH, 1);
> +		input_sync(st->ts_input);
> +	} else {
> +		dev_dbg(&idev->dev, "pressure too low: not reporting\n");
> +	}
> +
> +	return 0;
> +}
> +
> +static irqreturn_t at91_adc_interrupt(int irq, void *private)
> +{
> +	struct iio_dev *idev = private;
> +	struct at91_adc_state *st = iio_priv(idev);
> +	u32 status = at91_adc_readl(st, st->registers->status_register);
> +	const uint32_t ts_data_irq_mask =
> +		AT91_ADC_IER_XRDY |
> +		AT91_ADC_IER_YRDY |
> +		AT91_ADC_IER_PRDY;
> +
> +	if (status & st->registers->drdy_mask)
> +		handle_adc_eoc_trigger(irq, idev);
> +
> +	if (status & AT91_ADC_IER_PEN) {
> +		at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_PEN);
> +		at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_NOPEN |
> +			ts_data_irq_mask);
> +		/* Set up period trigger for sampling */
> +		at91_adc_writel(st, st->registers->trigger_register,
> +			AT91_ADC_TRGR_MOD_PERIOD_TRIG |
> +			AT91_ADC_TRGR_TRGPER_(st->ts_sample_period_val));
> +	} else if (status & AT91_ADC_IER_NOPEN) {
> +		at91_adc_writel(st, st->registers->trigger_register, 0);
> +		at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_NOPEN |
> +			ts_data_irq_mask);
> +		at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_PEN);
> +
> +		input_report_key(st->ts_input, BTN_TOUCH, 0);
> +		input_sync(st->ts_input);
> +	} else if ((status & ts_data_irq_mask) == ts_data_irq_mask) {
> +		/* Now all touchscreen data is ready */
> +
> +		if (status & AT91_ADC_ISR_PENS) {
> +			/* validate data by pen contact */
> +			at91_ts_sample(st);
> +		} else {
> +			/* triggered by event that is no pen contact, just read
> +			 * them to clean the interrupt and discard all.
> +			 */
> +			at91_adc_readl(st, AT91_ADC_TSXPOSR);
> +			at91_adc_readl(st, AT91_ADC_TSYPOSR);
> +			at91_adc_readl(st, AT91_ADC_TSPRESSR);
> +		}
> +	}
>   
>   	return IRQ_HANDLED;
>   }
> @@ -131,6 +279,16 @@ static int at91_adc_channel_init(struct iio_dev *idev)
>   	struct at91_adc_state *st = iio_priv(idev);
>   	struct iio_chan_spec *chan_array, *timestamp;
>   	int bit, idx = 0;
> +	unsigned long rsvd_mask = 0;
> +
> +	/* If touchscreen is enable, then reserve the adc channels */
> +	if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_4WIRE)
> +		rsvd_mask = CHAN_MASK_TOUCHSCREEN_4WIRE;
> +	else if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_5WIRE)
> +		rsvd_mask = CHAN_MASK_TOUCHSCREEN_5WIRE;
> +
> +	/* set up the channel mask to reserve touchscreen channels */
> +	st->channels_mask &= ~rsvd_mask;
>   
>   	idev->num_channels = bitmap_weight(&st->channels_mask,
>   					   st->num_channels) + 1;
> @@ -479,6 +637,39 @@ static u32 calc_startup_ticks_9x5(u8 startup_time, u32 adc_clk_khz)
>   
>   static const struct of_device_id at91_adc_dt_ids[];
>   
> +static int at91_adc_probe_dt_ts(struct device_node *node,
> +	struct at91_adc_state *st, struct device *dev)
> +{
> +	int ret;
> +	u32 prop;
> +
> +	ret = of_property_read_u32(node, "atmel,adc-ts-wires", &prop);
> +	if (ret) {
> +		dev_info(dev, "ADC Touch screen is disabled.\n");
> +		return 0;
> +	}
> +
> +	switch (prop) {
> +	case 4:
> +	case 5:
> +		st->touchscreen_type = prop;
> +		break;
> +	default:
> +		dev_err(dev, "Unsupported number of touchscreen wires (%d). Should be 4 or 5.\n", prop);
> +		return -EINVAL;
> +	}
> +
> +	prop = 0;
> +	of_property_read_u32(node, "atmel,adc-ts-pressure-threshold", &prop);
> +	st->ts_pressure_threshold = prop;
> +	if (st->ts_pressure_threshold) {
> +		return 0;
> +	} else {
> +		dev_err(dev, "Invalid pressure threshold for the touchscreen\n");
> +		return -EINVAL;
> +	}
> +}
> +
>   static int at91_adc_probe_dt(struct at91_adc_state *st,
>   			     struct platform_device *pdev)
>   {
> @@ -560,6 +751,12 @@ static int at91_adc_probe_dt(struct at91_adc_state *st,
>   		i++;
>   	}
>   
> +	/* Check if touchscreen is supported. */
> +	if (st->caps->has_ts)
> +		return at91_adc_probe_dt_ts(node, st, &idev->dev);
> +	else
> +		dev_info(&idev->dev, "not support touchscreen in the adc compatible string.\n");
> +
>   	return 0;
>   
>   error_ret:
> @@ -591,6 +788,114 @@ static const struct iio_info at91_adc_info = {
>   	.read_raw = &at91_adc_read_raw,
>   };
>   
> +/* Touchscreen related functions */
> +static int atmel_ts_open(struct input_dev *dev)
> +{
> +	struct at91_adc_state *st = input_get_drvdata(dev);
> +
> +	at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_PEN);
> +	return 0;
> +}
> +
> +static void atmel_ts_close(struct input_dev *dev)
> +{
> +	struct at91_adc_state *st = input_get_drvdata(dev);
> +
> +	at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_PEN);
> +}
> +
> +static int at91_ts_hw_init(struct at91_adc_state *st, u32 adc_clk_khz)
> +{
> +	u32 reg = 0, pendbc;
> +	int i = 0;
> +
> +	if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_4WIRE)
> +		reg = AT91_ADC_TSMR_TSMODE_4WIRE_PRESS;
> +	else
> +		reg = AT91_ADC_TSMR_TSMODE_5WIRE;
> +
> +	/* a Pen Detect Debounce Time is necessary for the ADC Touch to avoid
> +	 * pen detect noise.
> +	 * The formula is : Pen Detect Debounce Time = (2 ^ pendbc) / ADCClock
> +	 */
> +	pendbc = round_up(TOUCH_PEN_DETECT_DEBOUNCE_US * adc_clk_khz / 1000, 1);
> +
> +	while (pendbc >> ++i)
> +		;	/* Empty! Find the shift offset */
> +	if (abs(pendbc - (1 << i)) < abs(pendbc - (1 << (i - 1))))
> +		pendbc = i;
> +	else
> +		pendbc = i - 1;
> +
> +	if (st->caps->has_tsmr) {
> +		reg |= AT91_ADC_TSMR_TSAV_(st->caps->ts_filter_average)
> +				& AT91_ADC_TSMR_TSAV;
> +		reg |= AT91_ADC_TSMR_PENDBC_(pendbc) & AT91_ADC_TSMR_PENDBC;
> +		reg |= AT91_ADC_TSMR_NOTSDMA;
> +		reg |= AT91_ADC_TSMR_PENDET_ENA;
> +		reg |= 0x03 << 8;	/* TSFREQ, need bigger than TSAV */
> +
> +		at91_adc_writel(st, AT91_ADC_TSMR, reg);
> +	} else {
> +		/* TODO: for 9g45 which has no TSMR */
> +	}
> +
> +	/* Change adc internal resistor value for better pen detection,
> +	 * default value is 100 kOhm.
> +	 * 0 = 200 kOhm, 1 = 150 kOhm, 2 = 100 kOhm, 3 = 50 kOhm
> +	 * option only available on ES2 and higher
> +	 */
> +	at91_adc_writel(st, AT91_ADC_ACR, st->caps->ts_pen_detect_sensitivity
> +			& AT91_ADC_ACR_PENDETSENS);
> +
> +	/* Sample Peroid Time = (TRGPER + 1) / ADCClock */
> +	st->ts_sample_period_val = round_up((TOUCH_SAMPLE_PERIOD_US *
> +			adc_clk_khz / 1000) - 1, 1);
> +
> +	return 0;
> +}
> +
> +static int at91_ts_register(struct at91_adc_state *st,
> +		struct platform_device *pdev)
> +{
> +	struct input_dev *input;
> +	struct iio_dev *idev = iio_priv_to_dev(st);
> +	int ret;
> +
> +	input = input_allocate_device();
> +	if (!input) {
> +		dev_err(&idev->dev, "Failed to allocate TS device!\n");
> +		return -ENOMEM;
> +	}
> +
> +	input->name = DRIVER_NAME;
> +	input->id.bustype = BUS_HOST;
> +	input->dev.parent = &pdev->dev;
> +	input->open = atmel_ts_open;
> +	input->close = atmel_ts_close;
> +
> +	__set_bit(EV_ABS, input->evbit);
> +	__set_bit(EV_KEY, input->evbit);
> +	__set_bit(BTN_TOUCH, input->keybit);
> +	input_set_abs_params(input, ABS_X, 0, (1 << MAX_POS_BITS) - 1, 0, 0);
> +	input_set_abs_params(input, ABS_Y, 0, (1 << MAX_POS_BITS) - 1, 0, 0);
> +	input_set_abs_params(input, ABS_PRESSURE, 0, 0xffffff, 0, 0);
> +
> +	st->ts_input = input;
> +	input_set_drvdata(input, st);
> +
> +	ret = input_register_device(input);
> +	if (ret)
> +		input_free_device(st->ts_input);
> +
> +	return ret;
> +}
> +
> +static void at91_ts_unregister(struct at91_adc_state *st)
> +{
> +	input_unregister_device(st->ts_input);
> +}
> +
>   static int at91_adc_probe(struct platform_device *pdev)
>   {
>   	unsigned int prsc, mstrclk, ticks, adc_clk, adc_clk_khz, shtim;
> @@ -647,7 +952,7 @@ static int at91_adc_probe(struct platform_device *pdev)
>   	at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_SWRST);
>   	at91_adc_writel(st, AT91_ADC_IDR, 0xFFFFFFFF);
>   	ret = request_irq(st->irq,
> -			  at91_adc_eoc_trigger,
> +			  at91_adc_interrupt,
>   			  0,
>   			  pdev->dev.driver->name,
>   			  idev);
> @@ -692,6 +997,10 @@ static int at91_adc_probe(struct platform_device *pdev)
>   	mstrclk = clk_get_rate(st->clk);
>   	adc_clk = clk_get_rate(st->adc_clk);
>   	adc_clk_khz = adc_clk / 1000;
> +
> +	dev_dbg(&pdev->dev, "Master clock is set as: %d Hz, adc_clk should set as: %d Hz\n",
> +		mstrclk, adc_clk);
> +
>   	prsc = (mstrclk / (2 * adc_clk)) - 1;
>   
>   	if (!st->startup_time) {
> @@ -728,30 +1037,52 @@ static int at91_adc_probe(struct platform_device *pdev)
>   	init_waitqueue_head(&st->wq_data_avail);
>   	mutex_init(&st->lock);
>   
> -	ret = at91_adc_buffer_init(idev);
> -	if (ret < 0) {
> -		dev_err(&pdev->dev, "Couldn't initialize the buffer.\n");
> -		goto error_disable_adc_clk;
> -	}
> +	/*
> +	 * Since touch screen will set trigger register as period trigger. So
> +	 * when touch screen is enabled, then we have to disable hardware
> +	 * trigger for classic adc.
> +	 */
> +	if (!st->touchscreen_type) {
> +		ret = at91_adc_buffer_init(idev);
> +		if (ret < 0) {
> +			dev_err(&pdev->dev, "Couldn't initialize the buffer.\n");
> +			goto error_disable_adc_clk;
> +		}
>   
> -	ret = at91_adc_trigger_init(idev);
> -	if (ret < 0) {
> -		dev_err(&pdev->dev, "Couldn't setup the triggers.\n");
> -		goto error_unregister_buffer;
> +		ret = at91_adc_trigger_init(idev);
> +		if (ret < 0) {
> +			dev_err(&pdev->dev, "Couldn't setup the triggers.\n");
> +			at91_adc_buffer_remove(idev);
> +			goto error_disable_adc_clk;
> +		}
> +	} else {
> +		if (!st->caps->has_tsmr) {
> +			dev_err(&pdev->dev, "We don't support non-TSMR adc\n");
> +			goto error_disable_adc_clk;
> +		}
> +
> +		ret = at91_ts_register(st, pdev);
> +		if (ret)
> +			goto error_disable_adc_clk;
> +
> +		at91_ts_hw_init(st, adc_clk_khz);
>   	}
>   
>   	ret = iio_device_register(idev);
>   	if (ret < 0) {
>   		dev_err(&pdev->dev, "Couldn't register the device.\n");
> -		goto error_remove_triggers;
> +		goto error_iio_device_register;
>   	}
>   
>   	return 0;
>   
> -error_remove_triggers:
> -	at91_adc_trigger_remove(idev);
> -error_unregister_buffer:
> -	at91_adc_buffer_remove(idev);
> +error_iio_device_register:
> +	if (!st->touchscreen_type) {
> +		at91_adc_trigger_remove(idev);
> +		at91_adc_buffer_remove(idev);
> +	} else {
> +		at91_ts_unregister(st);
> +	}
>   error_disable_adc_clk:
>   	clk_disable_unprepare(st->adc_clk);
>   error_disable_clk:
> @@ -770,8 +1101,12 @@ static int at91_adc_remove(struct platform_device *pdev)
>   	struct at91_adc_state *st = iio_priv(idev);
>   
>   	iio_device_unregister(idev);
> -	at91_adc_trigger_remove(idev);
> -	at91_adc_buffer_remove(idev);
> +	if (!st->touchscreen_type) {
> +		at91_adc_trigger_remove(idev);
> +		at91_adc_buffer_remove(idev);
> +	} else {
> +		at91_ts_unregister(st);
> +	}
>   	clk_disable_unprepare(st->adc_clk);
>   	clk_disable_unprepare(st->clk);
>   	free_irq(st->irq, idev);
> @@ -795,6 +1130,7 @@ static struct at91_adc_caps at91sam9260_caps = {
>   };
>   
>   static struct at91_adc_caps at91sam9g45_caps = {
> +	.has_ts = true,
>   	.calc_startup_ticks = calc_startup_ticks_9260,	/* same as 9260 */
>   	.num_channels = 8,
>   	.registers = {
> @@ -808,6 +1144,10 @@ static struct at91_adc_caps at91sam9g45_caps = {
>   };
>   
>   static struct at91_adc_caps at91sam9x5_caps = {
> +	.has_ts = true,
> +	.has_tsmr = true,
> +	.ts_filter_average = 3,
> +	.ts_pen_detect_sensitivity = 2,
>   	.calc_startup_ticks = calc_startup_ticks_9x5,
>   	.num_channels = 12,
>   	.registers = {
> @@ -834,7 +1174,7 @@ static struct platform_driver at91_adc_driver = {
>   	.probe = at91_adc_probe,
>   	.remove = at91_adc_remove,
>   	.driver = {
> -		   .name = "at91_adc",
> +		   .name = DRIVER_NAME,
>   		   .of_match_table = of_match_ptr(at91_adc_dt_ids),
>   	},
>   };




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