iio: adc: at91_adc: Add support for touchscreens without TSMR (84882b06) · Commits · e / devices / android_kernel_fairphone_FP4

arch/arm/mach-at91/include/mach/at91_adc.h

+13 −0

Original line number	Original line	Diff line number	Diff line
	@@ -20,6 +20,9 @@
	#define AT91_ADC_START (1 << 1) /* Start Conversion */		#define AT91_ADC_START (1 << 1) /* Start Conversion */

	#define AT91_ADC_MR 0x04 /* Mode Register */		#define AT91_ADC_MR 0x04 /* Mode Register */
			#define AT91_ADC_TSAMOD (3 << 0) /* ADC mode */
			#define AT91_ADC_TSAMOD_ADC_ONLY_MODE (0 << 0) /* ADC Mode */
			#define AT91_ADC_TSAMOD_TS_ONLY_MODE (1 << 0) /* Touch Screen Only Mode */
	#define AT91_ADC_TRGEN (1 << 0) /* Trigger Enable */		#define AT91_ADC_TRGEN (1 << 0) /* Trigger Enable */
	#define AT91_ADC_TRGSEL (7 << 1) /* Trigger Selection */		#define AT91_ADC_TRGSEL (7 << 1) /* Trigger Selection */
	#define AT91_ADC_TRGSEL_TC0 (0 << 1)		#define AT91_ADC_TRGSEL_TC0 (0 << 1)
	@@ -28,6 +31,7 @@
	#define AT91_ADC_TRGSEL_EXTERNAL (6 << 1)		#define AT91_ADC_TRGSEL_EXTERNAL (6 << 1)
	#define AT91_ADC_LOWRES (1 << 4) /* Low Resolution */		#define AT91_ADC_LOWRES (1 << 4) /* Low Resolution */
	#define AT91_ADC_SLEEP (1 << 5) /* Sleep Mode */		#define AT91_ADC_SLEEP (1 << 5) /* Sleep Mode */
			#define AT91_ADC_PENDET (1 << 6) /* Pen contact detection enable */
	#define AT91_ADC_PRESCAL_9260 (0x3f << 8) /* Prescalar Rate Selection */		#define AT91_ADC_PRESCAL_9260 (0x3f << 8) /* Prescalar Rate Selection */
	#define AT91_ADC_PRESCAL_9G45 (0xff << 8)		#define AT91_ADC_PRESCAL_9G45 (0xff << 8)
	#define AT91_ADC_PRESCAL_(x) ((x) << 8)		#define AT91_ADC_PRESCAL_(x) ((x) << 8)
	@@ -37,6 +41,12 @@
	#define AT91_ADC_STARTUP_(x) ((x) << 16)		#define AT91_ADC_STARTUP_(x) ((x) << 16)
	#define AT91_ADC_SHTIM (0xf << 24) /* Sample & Hold Time */		#define AT91_ADC_SHTIM (0xf << 24) /* Sample & Hold Time */
	#define AT91_ADC_SHTIM_(x) ((x) << 24)		#define AT91_ADC_SHTIM_(x) ((x) << 24)
			#define AT91_ADC_PENDBC (0x0f << 28) /* Pen Debounce time */
			#define AT91_ADC_PENDBC_(x) ((x) << 28)

			#define AT91_ADC_TSR 0x0C
			#define AT91_ADC_TSR_SHTIM (0xf << 24) /* Sample & Hold Time */
			#define AT91_ADC_TSR_SHTIM_(x) ((x) << 24)

	#define AT91_ADC_CHER 0x10 /* Channel Enable Register */		#define AT91_ADC_CHER 0x10 /* Channel Enable Register */
	#define AT91_ADC_CHDR 0x14 /* Channel Disable Register */		#define AT91_ADC_CHDR 0x14 /* Channel Disable Register */
	@@ -60,6 +70,8 @@
	#define AT91_ADC_IER 0x24 /* Interrupt Enable Register */		#define AT91_ADC_IER 0x24 /* Interrupt Enable Register */
	#define AT91_ADC_IDR 0x28 /* Interrupt Disable Register */		#define AT91_ADC_IDR 0x28 /* Interrupt Disable Register */
	#define AT91_ADC_IMR 0x2C /* Interrupt Mask Register */		#define AT91_ADC_IMR 0x2C /* Interrupt Mask Register */
			#define AT91RL_ADC_IER_PEN (1 << 20)
			#define AT91RL_ADC_IER_NOPEN (1 << 21)
	#define AT91_ADC_IER_PEN (1 << 29)		#define AT91_ADC_IER_PEN (1 << 29)
	#define AT91_ADC_IER_NOPEN (1 << 30)		#define AT91_ADC_IER_NOPEN (1 << 30)
	#define AT91_ADC_IER_XRDY (1 << 20)		#define AT91_ADC_IER_XRDY (1 << 20)
	@@ -102,6 +114,7 @@
	#define AT91_ADC_TRGR_TRGPER (0xffff << 16)		#define AT91_ADC_TRGR_TRGPER (0xffff << 16)
	#define AT91_ADC_TRGR_TRGPER_(x) ((x) << 16)		#define AT91_ADC_TRGR_TRGPER_(x) ((x) << 16)
	#define AT91_ADC_TRGR_TRGMOD (0x7 << 0)		#define AT91_ADC_TRGR_TRGMOD (0x7 << 0)
			#define AT91_ADC_TRGR_NONE (0 << 0)
	#define AT91_ADC_TRGR_MOD_PERIOD_TRIG (5 << 0)		#define AT91_ADC_TRGR_MOD_PERIOD_TRIG (5 << 0)

	#endif		#endif

drivers/iio/adc/at91_adc.c

+153 −47

Original line number	Original line	Diff line number	Diff line
	@@ -46,6 +46,10 @@
	#define TOUCH_SAMPLE_PERIOD_US 2000 /* 2ms */		#define TOUCH_SAMPLE_PERIOD_US 2000 /* 2ms */
	#define TOUCH_PEN_DETECT_DEBOUNCE_US 200		#define TOUCH_PEN_DETECT_DEBOUNCE_US 200

			#define MAX_RLPOS_BITS 10
			#define TOUCH_SAMPLE_PERIOD_US_RL 10000 /* 10ms, the SoC can't keep up with 2ms */
			#define TOUCH_SHTIM 0xa

	/**		/**
	* struct at91_adc_reg_desc - Various informations relative to registers		* struct at91_adc_reg_desc - Various informations relative to registers
	* @channel_base: Base offset for the channel data registers		* @channel_base: Base offset for the channel data registers
	@@ -83,12 +87,6 @@ struct at91_adc_caps {
	struct at91_adc_reg_desc registers;		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 at91_adc_state {
	struct clk *adc_clk;		struct clk *adc_clk;
	u16 *buffer;		u16 *buffer;
	@@ -133,6 +131,11 @@ struct at91_adc_state {

	u16 ts_sample_period_val;		u16 ts_sample_period_val;
	u32 ts_pressure_threshold;		u32 ts_pressure_threshold;
			u16 ts_pendbc;

			bool ts_bufferedmeasure;
			u32 ts_prev_absx;
			u32 ts_prev_absy;
	};		};

	static irqreturn_t at91_adc_trigger_handler(int irq, void *p)		static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
	@@ -239,7 +242,72 @@ static int at91_ts_sample(struct at91_adc_state *st)
	return 0;		return 0;
	}		}

	static irqreturn_t at91_adc_interrupt(int irq, void *private)		static irqreturn_t at91_adc_rl_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);
			unsigned int reg;

			status &= at91_adc_readl(st, AT91_ADC_IMR);
			if (status & st->registers->drdy_mask)
			handle_adc_eoc_trigger(irq, idev);

			if (status & AT91RL_ADC_IER_PEN) {
			/* Disabling pen debounce is required to get a NOPEN irq */
			reg = at91_adc_readl(st, AT91_ADC_MR);
			reg &= ~AT91_ADC_PENDBC;
			at91_adc_writel(st, AT91_ADC_MR, reg);

			at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_PEN);
			at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_NOPEN
			\| AT91_ADC_EOC(3));
			/* 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 & AT91RL_ADC_IER_NOPEN) {
			reg = at91_adc_readl(st, AT91_ADC_MR);
			reg \|= AT91_ADC_PENDBC_(st->ts_pendbc) & AT91_ADC_PENDBC;
			at91_adc_writel(st, AT91_ADC_MR, reg);
			at91_adc_writel(st, st->registers->trigger_register,
			AT91_ADC_TRGR_NONE);

			at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_NOPEN
			\| AT91_ADC_EOC(3));
			at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_PEN);
			st->ts_bufferedmeasure = false;
			input_report_key(st->ts_input, BTN_TOUCH, 0);
			input_sync(st->ts_input);
			} else if (status & AT91_ADC_EOC(3)) {
			/* Conversion finished */
			if (st->ts_bufferedmeasure) {
			/*
			* Last measurement is always discarded, since it can
			* be erroneous.
			* Always report previous measurement
			*/
			input_report_abs(st->ts_input, ABS_X, st->ts_prev_absx);
			input_report_abs(st->ts_input, ABS_Y, st->ts_prev_absy);
			input_report_key(st->ts_input, BTN_TOUCH, 1);
			input_sync(st->ts_input);
			} else
			st->ts_bufferedmeasure = true;

			/* Now make new measurement */
			st->ts_prev_absx = at91_adc_readl(st, AT91_ADC_CHAN(st, 3))
			<< MAX_RLPOS_BITS;
			st->ts_prev_absx /= at91_adc_readl(st, AT91_ADC_CHAN(st, 2));

			st->ts_prev_absy = at91_adc_readl(st, AT91_ADC_CHAN(st, 1))
			<< MAX_RLPOS_BITS;
			st->ts_prev_absy /= at91_adc_readl(st, AT91_ADC_CHAN(st, 0));
			}

			return IRQ_HANDLED;
			}

			static irqreturn_t at91_adc_9x5_interrupt(int irq, void *private)
	{		{
	struct iio_dev *idev = private;		struct iio_dev *idev = private;
	struct at91_adc_state *st = iio_priv(idev);		struct at91_adc_state *st = iio_priv(idev);
	@@ -672,6 +740,8 @@ static int at91_adc_probe_dt_ts(struct device_node *node,
	return -EINVAL;		return -EINVAL;
	}		}

			if (!st->caps->has_tsmr)
			return 0;
	prop = 0;		prop = 0;
	of_property_read_u32(node, "atmel,adc-ts-pressure-threshold", &prop);		of_property_read_u32(node, "atmel,adc-ts-pressure-threshold", &prop);
	st->ts_pressure_threshold = prop;		st->ts_pressure_threshold = prop;
	@@ -795,6 +865,7 @@ static int at91_adc_probe_pdata(struct at91_adc_state *st,
	st->trigger_number = pdata->trigger_number;		st->trigger_number = pdata->trigger_number;
	st->trigger_list = pdata->trigger_list;		st->trigger_list = pdata->trigger_list;
	st->registers = &st->caps->registers;		st->registers = &st->caps->registers;
			st->touchscreen_type = pdata->touchscreen_type;

	return 0;		return 0;
	}		}
	@@ -809,7 +880,10 @@ static int atmel_ts_open(struct input_dev *dev)
	{		{
	struct at91_adc_state *st = input_get_drvdata(dev);		struct at91_adc_state *st = input_get_drvdata(dev);

			if (st->caps->has_tsmr)
	at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_PEN);		at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_PEN);
			else
			at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_PEN);
	return 0;		return 0;
	}		}

	@@ -817,44 +891,60 @@ static void atmel_ts_close(struct input_dev *dev)
	{		{
	struct at91_adc_state *st = input_get_drvdata(dev);		struct at91_adc_state *st = input_get_drvdata(dev);

			if (st->caps->has_tsmr)
	at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_PEN);		at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_PEN);
			else
			at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_PEN);
	}		}

	static int at91_ts_hw_init(struct at91_adc_state *st, u32 adc_clk_khz)		static int at91_ts_hw_init(struct at91_adc_state *st, u32 adc_clk_khz)
	{		{
	u32 reg = 0, pendbc;		u32 reg = 0;
	int i = 0;		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		/* a Pen Detect Debounce Time is necessary for the ADC Touch to avoid
	* pen detect noise.		* pen detect noise.
	* The formula is : Pen Detect Debounce Time = (2 ^ pendbc) / ADCClock		* The formula is : Pen Detect Debounce Time = (2 ^ pendbc) / ADCClock
	*/		*/
	pendbc = round_up(TOUCH_PEN_DETECT_DEBOUNCE_US * adc_clk_khz / 1000, 1);		st->ts_pendbc = round_up(TOUCH_PEN_DETECT_DEBOUNCE_US * adc_clk_khz /
			1000, 1);

	while (pendbc >> ++i)		while (st->ts_pendbc >> ++i)
	; /* Empty! Find the shift offset */		; /* Empty! Find the shift offset */
	if (abs(pendbc - (1 << i)) < abs(pendbc - (1 << (i - 1))))		if (abs(st->ts_pendbc - (1 << i)) < abs(st->ts_pendbc - (1 << (i - 1))))
	pendbc = i;		st->ts_pendbc = i;
	else		else
	pendbc = i - 1;		st->ts_pendbc = i - 1;

			if (!st->caps->has_tsmr) {
			reg = at91_adc_readl(st, AT91_ADC_MR);
			reg \|= AT91_ADC_TSAMOD_TS_ONLY_MODE \| AT91_ADC_PENDET;

			reg \|= AT91_ADC_PENDBC_(st->ts_pendbc) & AT91_ADC_PENDBC;
			at91_adc_writel(st, AT91_ADC_MR, reg);

			reg = AT91_ADC_TSR_SHTIM_(TOUCH_SHTIM) & AT91_ADC_TSR_SHTIM;
			at91_adc_writel(st, AT91_ADC_TSR, reg);

			st->ts_sample_period_val = round_up((TOUCH_SAMPLE_PERIOD_US_RL *
			adc_clk_khz / 1000) - 1, 1);

			return 0;
			}

			if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_4WIRE)
			reg = AT91_ADC_TSMR_TSMODE_4WIRE_PRESS;
			else
			reg = AT91_ADC_TSMR_TSMODE_5WIRE;

	if (st->caps->has_tsmr) {
	reg \|= AT91_ADC_TSMR_TSAV_(st->caps->ts_filter_average)		reg \|= AT91_ADC_TSMR_TSAV_(st->caps->ts_filter_average)
	& AT91_ADC_TSMR_TSAV;		& AT91_ADC_TSMR_TSAV;
	reg \|= AT91_ADC_TSMR_PENDBC_(pendbc) & AT91_ADC_TSMR_PENDBC;		reg \|= AT91_ADC_TSMR_PENDBC_(st->ts_pendbc) & AT91_ADC_TSMR_PENDBC;
	reg \|= AT91_ADC_TSMR_NOTSDMA;		reg \|= AT91_ADC_TSMR_NOTSDMA;
	reg \|= AT91_ADC_TSMR_PENDET_ENA;		reg \|= AT91_ADC_TSMR_PENDET_ENA;
	reg \|= 0x03 << 8; /* TSFREQ, need bigger than TSAV */		reg \|= 0x03 << 8; /* TSFREQ, needs to be bigger than TSAV */

	at91_adc_writel(st, AT91_ADC_TSMR, reg);		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,		/* Change adc internal resistor value for better pen detection,
	* default value is 100 kOhm.		* default value is 100 kOhm.
	@@ -864,7 +954,7 @@ static int at91_ts_hw_init(struct at91_adc_state *st, u32 adc_clk_khz)
	at91_adc_writel(st, AT91_ADC_ACR, st->caps->ts_pen_detect_sensitivity		at91_adc_writel(st, AT91_ADC_ACR, st->caps->ts_pen_detect_sensitivity
	& AT91_ADC_ACR_PENDETSENS);		& AT91_ADC_ACR_PENDETSENS);

	/* Sample Peroid Time = (TRGPER + 1) / ADCClock */		/* Sample Period Time = (TRGPER + 1) / ADCClock */
	st->ts_sample_period_val = round_up((TOUCH_SAMPLE_PERIOD_US *		st->ts_sample_period_val = round_up((TOUCH_SAMPLE_PERIOD_US *
	adc_clk_khz / 1000) - 1, 1);		adc_clk_khz / 1000) - 1, 1);

	@@ -893,18 +983,38 @@ static int at91_ts_register(struct at91_adc_state *st,
	__set_bit(EV_ABS, input->evbit);		__set_bit(EV_ABS, input->evbit);
	__set_bit(EV_KEY, input->evbit);		__set_bit(EV_KEY, input->evbit);
	__set_bit(BTN_TOUCH, input->keybit);		__set_bit(BTN_TOUCH, input->keybit);
	input_set_abs_params(input, ABS_X, 0, (1 << MAX_POS_BITS) - 1, 0, 0);		if (st->caps->has_tsmr) {
	input_set_abs_params(input, ABS_Y, 0, (1 << MAX_POS_BITS) - 1, 0, 0);		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);		input_set_abs_params(input, ABS_PRESSURE, 0, 0xffffff, 0, 0);
			} else {
			if (st->touchscreen_type != ATMEL_ADC_TOUCHSCREEN_4WIRE) {
			dev_err(&pdev->dev,
			"This touchscreen controller only support 4 wires\n");
			ret = -EINVAL;
			goto err;
			}

			input_set_abs_params(input, ABS_X, 0, (1 << MAX_RLPOS_BITS) - 1,
			0, 0);
			input_set_abs_params(input, ABS_Y, 0, (1 << MAX_RLPOS_BITS) - 1,
			0, 0);
			}

	st->ts_input = input;		st->ts_input = input;
	input_set_drvdata(input, st);		input_set_drvdata(input, st);

	ret = input_register_device(input);		ret = input_register_device(input);
	if (ret)		if (ret)
	input_free_device(st->ts_input);		goto err;

	return ret;		return ret;

			err:
			input_free_device(st->ts_input);
			return ret;
	}		}

	static void at91_ts_unregister(struct at91_adc_state *st)		static void at91_ts_unregister(struct at91_adc_state *st)
	@@ -962,11 +1072,13 @@ 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_CR, AT91_ADC_SWRST);
	at91_adc_writel(st, AT91_ADC_IDR, 0xFFFFFFFF);		at91_adc_writel(st, AT91_ADC_IDR, 0xFFFFFFFF);
	ret = request_irq(st->irq,
	at91_adc_interrupt,		if (st->caps->has_tsmr)
	0,		ret = request_irq(st->irq, at91_adc_9x5_interrupt, 0,
	pdev->dev.driver->name,		pdev->dev.driver->name, idev);
	idev);		else
			ret = request_irq(st->irq, at91_adc_rl_interrupt, 0,
			pdev->dev.driver->name, idev);
	if (ret) {		if (ret) {
	dev_err(&pdev->dev, "Failed to allocate IRQ.\n");		dev_err(&pdev->dev, "Failed to allocate IRQ.\n");
	return ret;		return ret;
	@@ -1070,12 +1182,6 @@ static int at91_adc_probe(struct platform_device *pdev)
	goto error_disable_adc_clk;		goto error_disable_adc_clk;
	}		}
	} else {		} else {
	if (!st->caps->has_tsmr) {
	dev_err(&pdev->dev, "We don't support non-TSMR adc\n");
	ret = -ENODEV;
	goto error_disable_adc_clk;
	}

	ret = at91_ts_register(st, pdev);		ret = at91_ts_register(st, pdev);
	if (ret)		if (ret)
	goto error_disable_adc_clk;		goto error_disable_adc_clk;

include/linux/platform_data/at91_adc.h

+8 −0

Original line number	Original line	Diff line number	Diff line
	@@ -7,6 +7,12 @@
	#ifndef _AT91_ADC_H_		#ifndef _AT91_ADC_H_
	#define _AT91_ADC_H_		#define _AT91_ADC_H_

			enum atmel_adc_ts_type {
			ATMEL_ADC_TOUCHSCREEN_NONE = 0,
			ATMEL_ADC_TOUCHSCREEN_4WIRE = 4,
			ATMEL_ADC_TOUCHSCREEN_5WIRE = 5,
			};

	/**		/**
	* struct at91_adc_trigger - description of triggers		* struct at91_adc_trigger - description of triggers
	* @name: name of the trigger advertised to the user		* @name: name of the trigger advertised to the user
	@@ -28,6 +34,7 @@ struct at91_adc_trigger {
	* @trigger_number: Number of triggers available in the ADC		* @trigger_number: Number of triggers available in the ADC
	* @use_external_triggers: does the board has external triggers availables		* @use_external_triggers: does the board has external triggers availables
	* @vref: Reference voltage for the ADC in millivolts		* @vref: Reference voltage for the ADC in millivolts
			* @touchscreen_type: If a touchscreen is connected, its type (4 or 5 wires)
	*/		*/
	struct at91_adc_data {		struct at91_adc_data {
	unsigned long channels_used;		unsigned long channels_used;
	@@ -36,6 +43,7 @@ struct at91_adc_data {
	u8 trigger_number;		u8 trigger_number;
	bool use_external_triggers;		bool use_external_triggers;
	u16 vref;		u16 vref;
			enum atmel_adc_ts_type touchscreen_type;
	};		};

	extern void __init at91_add_device_adc(struct at91_adc_data *data);		extern void __init at91_add_device_adc(struct at91_adc_data *data);