[linux-2.6-block.git] / drivers / input / touchscreen / ti_am335x_tsc.c

/*
 * TI Touch Screen driver
 *
 * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation version 2.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 * kind, whether express or implied; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */


#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/input.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/sort.h>
#include <linux/pm_wakeirq.h>

#include <linux/mfd/ti_am335x_tscadc.h>

#define ADCFSM_STEPID		0x10
#define SEQ_SETTLE		275
#define MAX_12BIT		((1 << 12) - 1)

#define TSC_IRQENB_MASK		(IRQENB_FIFO0THRES | IRQENB_EOS | IRQENB_HW_PEN)

static const int config_pins[] = {
	STEPCONFIG_XPP,
	STEPCONFIG_XNN,
	STEPCONFIG_YPP,
	STEPCONFIG_YNN,
};

struct titsc {
	struct input_dev	*input;
	struct ti_tscadc_dev	*mfd_tscadc;
	struct device		*dev;
	unsigned int		irq;
	unsigned int		wires;
	unsigned int		x_plate_resistance;
	bool			pen_down;
	int			coordinate_readouts;
	u32			config_inp[4];
	u32			bit_xp, bit_xn, bit_yp, bit_yn;
	u32			inp_xp, inp_xn, inp_yp, inp_yn;
	u32			step_mask;
	u32			charge_delay;
};

static unsigned int titsc_readl(struct titsc *ts, unsigned int reg)
{
	return readl(ts->mfd_tscadc->tscadc_base + reg);
}

static void titsc_writel(struct titsc *tsc, unsigned int reg,
					unsigned int val)
{
	writel(val, tsc->mfd_tscadc->tscadc_base + reg);
}

static int titsc_config_wires(struct titsc *ts_dev)
{
	u32 analog_line[4];
	u32 wire_order[4];
	int i, bit_cfg;

	for (i = 0; i < 4; i++) {
		/*
		 * Get the order in which TSC wires are attached
		 * w.r.t. each of the analog input lines on the EVM.
		 */
		analog_line[i] = (ts_dev->config_inp[i] & 0xF0) >> 4;
		wire_order[i] = ts_dev->config_inp[i] & 0x0F;
		if (WARN_ON(analog_line[i] > 7))
			return -EINVAL;
		if (WARN_ON(wire_order[i] > ARRAY_SIZE(config_pins)))
			return -EINVAL;
	}

	for (i = 0; i < 4; i++) {
		int an_line;
		int wi_order;

		an_line = analog_line[i];
		wi_order = wire_order[i];
		bit_cfg = config_pins[wi_order];
		if (bit_cfg == 0)
			return -EINVAL;
		switch (wi_order) {
		case 0:
			ts_dev->bit_xp = bit_cfg;
			ts_dev->inp_xp = an_line;
			break;

		case 1:
			ts_dev->bit_xn = bit_cfg;
			ts_dev->inp_xn = an_line;
			break;

		case 2:
			ts_dev->bit_yp = bit_cfg;
			ts_dev->inp_yp = an_line;
			break;
		case 3:
			ts_dev->bit_yn = bit_cfg;
			ts_dev->inp_yn = an_line;
			break;
		}
	}
	return 0;
}

static void titsc_step_config(struct titsc *ts_dev)
{
	unsigned int	config;
	int i, n;
	int end_step, first_step, tsc_steps;
	u32 stepenable;

	config = STEPCONFIG_MODE_HWSYNC |
			STEPCONFIG_AVG_16 | ts_dev->bit_xp |
			STEPCONFIG_INM_ADCREFM;
	switch (ts_dev->wires) {
	case 4:
		config |= STEPCONFIG_INP(ts_dev->inp_yp) | ts_dev->bit_xn;
		break;
	case 5:
		config |= ts_dev->bit_yn |
				STEPCONFIG_INP_AN4 | ts_dev->bit_xn |
				ts_dev->bit_yp;
		break;
	case 8:
		config |= STEPCONFIG_INP(ts_dev->inp_yp) | ts_dev->bit_xn;
		break;
	}

	tsc_steps = ts_dev->coordinate_readouts * 2 + 2;
	first_step = TOTAL_STEPS - tsc_steps;
	/* Steps 16 to 16-coordinate_readouts is for X */
	end_step = first_step + tsc_steps;
	n = 0;
	for (i = end_step - ts_dev->coordinate_readouts; i < end_step; i++) {
		titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
		titsc_writel(ts_dev, REG_STEPDELAY(i),
			     n++ == 0 ? STEPCONFIG_OPENDLY : 0);
	}

	config = STEPCONFIG_MODE_HWSYNC |
			STEPCONFIG_AVG_16 | ts_dev->bit_yn |
			STEPCONFIG_INM_ADCREFM;
	switch (ts_dev->wires) {
	case 4:
		config |= ts_dev->bit_yp | STEPCONFIG_INP(ts_dev->inp_xp);
		break;
	case 5:
		config |= ts_dev->bit_xp | STEPCONFIG_INP_AN4 |
				STEPCONFIG_XNP | STEPCONFIG_YPN;
		break;
	case 8:
		config |= ts_dev->bit_yp | STEPCONFIG_INP(ts_dev->inp_xp);
		break;
	}

	/* 1 ... coordinate_readouts is for Y */
	end_step = first_step + ts_dev->coordinate_readouts;
	n = 0;
	for (i = first_step; i < end_step; i++) {
		titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
		titsc_writel(ts_dev, REG_STEPDELAY(i),
			     n++ == 0 ? STEPCONFIG_OPENDLY : 0);
	}

	/* Make CHARGECONFIG same as IDLECONFIG */

	config = titsc_readl(ts_dev, REG_IDLECONFIG);
	titsc_writel(ts_dev, REG_CHARGECONFIG, config);
	titsc_writel(ts_dev, REG_CHARGEDELAY, ts_dev->charge_delay);

	/* coordinate_readouts + 1 ... coordinate_readouts + 2 is for Z */
	config = STEPCONFIG_MODE_HWSYNC |
			STEPCONFIG_AVG_16 | ts_dev->bit_yp |
			ts_dev->bit_xn | STEPCONFIG_INM_ADCREFM |
			STEPCONFIG_INP(ts_dev->inp_xp);
	titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
	titsc_writel(ts_dev, REG_STEPDELAY(end_step),
			STEPCONFIG_OPENDLY);

	end_step++;
	config = STEPCONFIG_MODE_HWSYNC |
			STEPCONFIG_AVG_16 | ts_dev->bit_yp |
			ts_dev->bit_xn | STEPCONFIG_INM_ADCREFM |
			STEPCONFIG_INP(ts_dev->inp_yn);
	titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
	titsc_writel(ts_dev, REG_STEPDELAY(end_step),
			STEPCONFIG_OPENDLY);

	/* The steps end ... end - readouts * 2 + 2 and bit 0 for TS_Charge */
	stepenable = 1;
	for (i = 0; i < tsc_steps; i++)
		stepenable |= 1 << (first_step + i + 1);

	ts_dev->step_mask = stepenable;
	am335x_tsc_se_set_cache(ts_dev->mfd_tscadc, ts_dev->step_mask);
}

static int titsc_cmp_coord(const void *a, const void *b)
{
	return *(int *)a - *(int *)b;
}

static void titsc_read_coordinates(struct titsc *ts_dev,
		u32 *x, u32 *y, u32 *z1, u32 *z2)
{
	unsigned int yvals[7], xvals[7];
	unsigned int i, xsum = 0, ysum = 0;
	unsigned int creads = ts_dev->coordinate_readouts;

	for (i = 0; i < creads; i++) {
		yvals[i] = titsc_readl(ts_dev, REG_FIFO0);
		yvals[i] &= 0xfff;
	}

	*z1 = titsc_readl(ts_dev, REG_FIFO0);
	*z1 &= 0xfff;
	*z2 = titsc_readl(ts_dev, REG_FIFO0);
	*z2 &= 0xfff;

	for (i = 0; i < creads; i++) {
		xvals[i] = titsc_readl(ts_dev, REG_FIFO0);
		xvals[i] &= 0xfff;
	}

	/*
	 * If co-ordinates readouts is less than 4 then
	 * report the average. In case of 4 or more
	 * readouts, sort the co-ordinate samples, drop
	 * min and max values and report the average of
	 * remaining values.
	 */
	if (creads <=  3) {
		for (i = 0; i < creads; i++) {
			ysum += yvals[i];
			xsum += xvals[i];
		}
		ysum /= creads;
		xsum /= creads;
	} else {
		sort(yvals, creads, sizeof(unsigned int),
		     titsc_cmp_coord, NULL);
		sort(xvals, creads, sizeof(unsigned int),
		     titsc_cmp_coord, NULL);
		for (i = 1; i < creads - 1; i++) {
			ysum += yvals[i];
			xsum += xvals[i];
		}
		ysum /= creads - 2;
		xsum /= creads - 2;
	}
	*y = ysum;
	*x = xsum;
}

static irqreturn_t titsc_irq(int irq, void *dev)
{
	struct titsc *ts_dev = dev;
	struct input_dev *input_dev = ts_dev->input;
	unsigned int fsm, status, irqclr = 0;
	unsigned int x = 0, y = 0;
	unsigned int z1, z2, z;

	status = titsc_readl(ts_dev, REG_RAWIRQSTATUS);
	if (status & IRQENB_HW_PEN) {
		ts_dev->pen_down = true;
		irqclr |= IRQENB_HW_PEN;
		pm_stay_awake(ts_dev->dev);
	}

	if (status & IRQENB_PENUP) {
		fsm = titsc_readl(ts_dev, REG_ADCFSM);
		if (fsm == ADCFSM_STEPID) {
			ts_dev->pen_down = false;
			input_report_key(input_dev, BTN_TOUCH, 0);
			input_report_abs(input_dev, ABS_PRESSURE, 0);
			input_sync(input_dev);
			pm_relax(ts_dev->dev);
		} else {
			ts_dev->pen_down = true;
		}
		irqclr |= IRQENB_PENUP;
	}

	if (status & IRQENB_EOS)
		irqclr |= IRQENB_EOS;

	/*
	 * ADC and touchscreen share the IRQ line.
	 * FIFO1 interrupts are used by ADC. Handle FIFO0 IRQs here only
	 */
	if (status & IRQENB_FIFO0THRES) {

		titsc_read_coordinates(ts_dev, &x, &y, &z1, &z2);

		if (ts_dev->pen_down && z1 != 0 && z2 != 0) {
			/*
			 * Calculate pressure using formula
			 * Resistance(touch) = x plate resistance *
			 * x position/4096 * ((z2 / z1) - 1)
			 */
			z = z1 - z2;
			z *= x;
			z *= ts_dev->x_plate_resistance;
			z /= z2;
			z = (z + 2047) >> 12;

			if (z <= MAX_12BIT) {
				input_report_abs(input_dev, ABS_X, x);
				input_report_abs(input_dev, ABS_Y, y);
				input_report_abs(input_dev, ABS_PRESSURE, z);
				input_report_key(input_dev, BTN_TOUCH, 1);
				input_sync(input_dev);
			}
		}
		irqclr |= IRQENB_FIFO0THRES;
	}
	if (irqclr) {
		titsc_writel(ts_dev, REG_IRQSTATUS, irqclr);
		if (status & IRQENB_EOS)
			am335x_tsc_se_set_cache(ts_dev->mfd_tscadc,
						ts_dev->step_mask);
		return IRQ_HANDLED;
	}
	return IRQ_NONE;
}

static int titsc_parse_dt(struct platform_device *pdev,
					struct titsc *ts_dev)
{
	struct device_node *node = pdev->dev.of_node;
	int err;

	if (!node)
		return -EINVAL;

	err = of_property_read_u32(node, "ti,wires", &ts_dev->wires);
	if (err < 0)
		return err;
	switch (ts_dev->wires) {
	case 4:
	case 5:
	case 8:
		break;
	default:
		return -EINVAL;
	}

	err = of_property_read_u32(node, "ti,x-plate-resistance",
			&ts_dev->x_plate_resistance);
	if (err < 0)
		return err;

	/*
	 * Try with the new binding first. If it fails, try again with
	 * bogus, miss-spelled version.
	 */
	err = of_property_read_u32(node, "ti,coordinate-readouts",
			&ts_dev->coordinate_readouts);
	if (err < 0) {
		dev_warn(&pdev->dev, "please use 'ti,coordinate-readouts' instead\n");
		err = of_property_read_u32(node, "ti,coordiante-readouts",
				&ts_dev->coordinate_readouts);
	}

	if (err < 0)
		return err;

	if (ts_dev->coordinate_readouts <= 0) {
		dev_warn(&pdev->dev,
			 "invalid co-ordinate readouts, resetting it to 5\n");
		ts_dev->coordinate_readouts = 5;
	}

	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");
	}

	return of_property_read_u32_array(node, "ti,wire-config",
			ts_dev->config_inp, ARRAY_SIZE(ts_dev->config_inp));
}

/*
 * The functions for inserting/removing driver as a module.
 */

static int titsc_probe(struct platform_device *pdev)
{
	struct titsc *ts_dev;
	struct input_dev *input_dev;
	struct ti_tscadc_dev *tscadc_dev = ti_tscadc_dev_get(pdev);
	int err;

	/* Allocate memory for device */
	ts_dev = kzalloc(sizeof(*ts_dev), GFP_KERNEL);
	input_dev = input_allocate_device();
	if (!ts_dev || !input_dev) {
		dev_err(&pdev->dev, "failed to allocate memory.\n");
		err = -ENOMEM;
		goto err_free_mem;
	}

	tscadc_dev->tsc = ts_dev;
	ts_dev->mfd_tscadc = tscadc_dev;
	ts_dev->input = input_dev;
	ts_dev->irq = tscadc_dev->irq;
	ts_dev->dev = &pdev->dev;

	err = titsc_parse_dt(pdev, ts_dev);
	if (err) {
		dev_err(&pdev->dev, "Could not find valid DT data.\n");
		goto err_free_mem;
	}

	err = request_irq(ts_dev->irq, titsc_irq,
			  IRQF_SHARED, pdev->dev.driver->name, ts_dev);
	if (err) {
		dev_err(&pdev->dev, "failed to allocate irq.\n");
		goto err_free_mem;
	}

	device_init_wakeup(&pdev->dev, true);
	err = dev_pm_set_wake_irq(&pdev->dev, ts_dev->irq);
	if (err)
		dev_err(&pdev->dev, "irq wake enable failed.\n");

	titsc_writel(ts_dev, REG_IRQSTATUS, TSC_IRQENB_MASK);
	titsc_writel(ts_dev, REG_IRQENABLE, IRQENB_FIFO0THRES);
	titsc_writel(ts_dev, REG_IRQENABLE, IRQENB_EOS);
	err = titsc_config_wires(ts_dev);
	if (err) {
		dev_err(&pdev->dev, "wrong i/p wire configuration\n");
		goto err_free_irq;
	}
	titsc_step_config(ts_dev);
	titsc_writel(ts_dev, REG_FIFO0THR,
			ts_dev->coordinate_readouts * 2 + 2 - 1);

	input_dev->name = "ti-tsc";
	input_dev->dev.parent = &pdev->dev;

	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
	input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);

	input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, 0, 0);
	input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0);
	input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT, 0, 0);

	/* register to the input system */
	err = input_register_device(input_dev);
	if (err)
		goto err_free_irq;

	platform_set_drvdata(pdev, ts_dev);
	return 0;

err_free_irq:
	dev_pm_clear_wake_irq(&pdev->dev);
	device_init_wakeup(&pdev->dev, false);
	free_irq(ts_dev->irq, ts_dev);
err_free_mem:
	input_free_device(input_dev);
	kfree(ts_dev);
	return err;
}

static void titsc_remove(struct platform_device *pdev)
{
	struct titsc *ts_dev = platform_get_drvdata(pdev);
	u32 steps;

	dev_pm_clear_wake_irq(&pdev->dev);
	device_init_wakeup(&pdev->dev, false);
	free_irq(ts_dev->irq, ts_dev);

	/* total steps followed by the enable mask */
	steps = 2 * ts_dev->coordinate_readouts + 2;
	steps = (1 << steps) - 1;
	am335x_tsc_se_clr(ts_dev->mfd_tscadc, steps);

	input_unregister_device(ts_dev->input);

	kfree(ts_dev);
}

static int titsc_suspend(struct device *dev)
{
	struct titsc *ts_dev = dev_get_drvdata(dev);
	unsigned int idle;

	if (device_may_wakeup(dev)) {
		titsc_writel(ts_dev, REG_IRQSTATUS, TSC_IRQENB_MASK);
		idle = titsc_readl(ts_dev, REG_IRQENABLE);
		titsc_writel(ts_dev, REG_IRQENABLE,
				(idle | IRQENB_HW_PEN));
		titsc_writel(ts_dev, REG_IRQWAKEUP, IRQWKUP_ENB);
	}
	return 0;
}

static int titsc_resume(struct device *dev)
{
	struct titsc *ts_dev = dev_get_drvdata(dev);

	if (device_may_wakeup(dev)) {
		titsc_writel(ts_dev, REG_IRQWAKEUP,
				0x00);
		titsc_writel(ts_dev, REG_IRQCLR, IRQENB_HW_PEN);
		pm_relax(dev);
	}
	titsc_step_config(ts_dev);
	titsc_writel(ts_dev, REG_FIFO0THR,
			ts_dev->coordinate_readouts * 2 + 2 - 1);
	return 0;
}

static DEFINE_SIMPLE_DEV_PM_OPS(titsc_pm_ops, titsc_suspend, titsc_resume);

static const struct of_device_id ti_tsc_dt_ids[] = {
	{ .compatible = "ti,am3359-tsc", },
	{ }
};
MODULE_DEVICE_TABLE(of, ti_tsc_dt_ids);

static struct platform_driver ti_tsc_driver = {
	.probe	= titsc_probe,
	.remove	= titsc_remove,
	.driver	= {
		.name	= "TI-am335x-tsc",
		.pm	= pm_sleep_ptr(&titsc_pm_ops),
		.of_match_table = ti_tsc_dt_ids,
	},
};
module_platform_driver(ti_tsc_driver);

MODULE_DESCRIPTION("TI touchscreen controller driver");
MODULE_AUTHOR("Rachna Patil <rachna@ti.com>");
MODULE_LICENSE("GPL");
Commit	Line	Data
1b8be32e RP	1	/*
	2	* TI Touch Screen driver
	3	*
	4	* Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License as
	8	* published by the Free Software Foundation version 2.
	9	*
	10	* This program is distributed "as is" WITHOUT ANY WARRANTY of any
	11	* kind, whether express or implied; without even the implied warranty
	12	* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	* GNU General Public License for more details.
	14	*/
	15
	16
1b8be32e RP	17	#include <linux/kernel.h>
	18	#include <linux/err.h>
	19	#include <linux/module.h>
	20	#include <linux/input.h>
	21	#include <linux/slab.h>
	22	#include <linux/interrupt.h>
	23	#include <linux/clk.h>
	24	#include <linux/platform_device.h>
	25	#include <linux/io.h>
1b8be32e	26	#include <linux/delay.h>
0396310b	27	#include <linux/of.h>
83edfdf3	28	#include <linux/sort.h>
7a39915b	29	#include <linux/pm_wakeirq.h>
1b8be32e	30
2b99bafa	31	#include <linux/mfd/ti_am335x_tscadc.h>
33f5cc60 PR	32
33f5cc60 PR	33	#define ADCFSM_STEPID 0x10
1b8be32e	34	#define SEQ_SETTLE 275
1b8be32e	35	#define MAX_12BIT ((1 << 12) - 1)
1b8be32e	36
46850420 GS	37	#define TSC_IRQENB_MASK (IRQENB_FIFO0THRES \| IRQENB_EOS \| IRQENB_HW_PEN)
46850420 GS	38
bb76dc09 PR	39	static const int config_pins[] = {
	40	STEPCONFIG_XPP,
	41	STEPCONFIG_XNN,
	42	STEPCONFIG_YPP,
	43	STEPCONFIG_YNN,
	44	};
	45
55c04de5	46	struct titsc {
1b8be32e	47	struct input_dev *input;
2b99bafa	48	struct ti_tscadc_dev *mfd_tscadc;
333e07ec	49	struct device *dev;
1b8be32e RP	50	unsigned int irq;
	51	unsigned int wires;
	52	unsigned int x_plate_resistance;
	53	bool pen_down;
0396310b	54	int coordinate_readouts;
bb76dc09 PR	55	u32 config_inp[4];
	56	u32 bit_xp, bit_xn, bit_yp, bit_yn;
	57	u32 inp_xp, inp_xn, inp_yp, inp_yn;
baee5399	58	u32 step_mask;
bf223612	59	u32 charge_delay;
1b8be32e RP	60	};
1b8be32e RP	61
55c04de5	62	static unsigned int titsc_readl(struct titsc *ts, unsigned int reg)
1b8be32e	63	{
2b99bafa	64	return readl(ts->mfd_tscadc->tscadc_base + reg);
1b8be32e RP	65	}
1b8be32e RP	66
55c04de5	67	static void titsc_writel(struct titsc *tsc, unsigned int reg,
1b8be32e RP	68	unsigned int val)
1b8be32e RP	69	{
2b99bafa	70	writel(val, tsc->mfd_tscadc->tscadc_base + reg);
1b8be32e RP	71	}
1b8be32e RP	72
bb76dc09 PR	73	static int titsc_config_wires(struct titsc *ts_dev)
	74	{
	75	u32 analog_line[4];
	76	u32 wire_order[4];
	77	int i, bit_cfg;
	78
	79	for (i = 0; i < 4; i++) {
	80	/*
	81	* Get the order in which TSC wires are attached
	82	* w.r.t. each of the analog input lines on the EVM.
	83	*/
	84	analog_line[i] = (ts_dev->config_inp[i] & 0xF0) >> 4;
	85	wire_order[i] = ts_dev->config_inp[i] & 0x0F;
	86	if (WARN_ON(analog_line[i] > 7))
	87	return -EINVAL;
	88	if (WARN_ON(wire_order[i] > ARRAY_SIZE(config_pins)))
	89	return -EINVAL;
	90	}
	91
	92	for (i = 0; i < 4; i++) {
	93	int an_line;
	94	int wi_order;
	95
	96	an_line = analog_line[i];
	97	wi_order = wire_order[i];
	98	bit_cfg = config_pins[wi_order];
	99	if (bit_cfg == 0)
	100	return -EINVAL;
	101	switch (wi_order) {
	102	case 0:
	103	ts_dev->bit_xp = bit_cfg;
	104	ts_dev->inp_xp = an_line;
	105	break;
	106
	107	case 1:
	108	ts_dev->bit_xn = bit_cfg;
	109	ts_dev->inp_xn = an_line;
	110	break;
	111
	112	case 2:
	113	ts_dev->bit_yp = bit_cfg;
	114	ts_dev->inp_yp = an_line;
	115	break;
	116	case 3:
	117	ts_dev->bit_yn = bit_cfg;
	118	ts_dev->inp_yn = an_line;
	119	break;
	120	}
	121	}
	122	return 0;
	123	}
	124
55c04de5	125	static void titsc_step_config(struct titsc *ts_dev)
1b8be32e RP	126	{
1b8be32e RP	127	unsigned int config;
23dee6c6	128	int i, n;
3a59684c	129	int end_step, first_step, tsc_steps;
8c896308	130	u32 stepenable;
1b8be32e RP	131
1b8be32e RP	132	config = STEPCONFIG_MODE_HWSYNC \|
73cca71a DB	133	STEPCONFIG_AVG_16 \| ts_dev->bit_xp \|
73cca71a DB	134	STEPCONFIG_INM_ADCREFM;
1b8be32e RP	135	switch (ts_dev->wires) {
1b8be32e RP	136	case 4:
bb76dc09	137	config \|= STEPCONFIG_INP(ts_dev->inp_yp) \| ts_dev->bit_xn;
1b8be32e RP	138	break;
1b8be32e RP	139	case 5:
bb76dc09 PR	140	config \|= ts_dev->bit_yn \|
	141	STEPCONFIG_INP_AN4 \| ts_dev->bit_xn \|
	142	ts_dev->bit_yp;
1b8be32e RP	143	break;
1b8be32e RP	144	case 8:
bb76dc09	145	config \|= STEPCONFIG_INP(ts_dev->inp_yp) \| ts_dev->bit_xn;
1b8be32e RP	146	break;
	147	}
	148
3a59684c BG	149	tsc_steps = ts_dev->coordinate_readouts * 2 + 2;
	150	first_step = TOTAL_STEPS - tsc_steps;
	151	/* Steps 16 to 16-coordinate_readouts is for X */
	152	end_step = first_step + tsc_steps;
23dee6c6	153	n = 0;
3a59684c	154	for (i = end_step - ts_dev->coordinate_readouts; i < end_step; i++) {
55c04de5	155	titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
23dee6c6 DB	156	titsc_writel(ts_dev, REG_STEPDELAY(i),
23dee6c6 DB	157	n++ == 0 ? STEPCONFIG_OPENDLY : 0);
1b8be32e RP	158	}
1b8be32e RP	159
1b8be32e	160	config = STEPCONFIG_MODE_HWSYNC \|
bb76dc09	161	STEPCONFIG_AVG_16 \| ts_dev->bit_yn \|
8c896308	162	STEPCONFIG_INM_ADCREFM;
1b8be32e RP	163	switch (ts_dev->wires) {
1b8be32e RP	164	case 4:
bb76dc09	165	config \|= ts_dev->bit_yp \| STEPCONFIG_INP(ts_dev->inp_xp);
1b8be32e RP	166	break;
1b8be32e RP	167	case 5:
bb76dc09	168	config \|= ts_dev->bit_xp \| STEPCONFIG_INP_AN4 \|
cf5dd489	169	STEPCONFIG_XNP \| STEPCONFIG_YPN;
1b8be32e RP	170	break;
1b8be32e RP	171	case 8:
bb76dc09	172	config \|= ts_dev->bit_yp \| STEPCONFIG_INP(ts_dev->inp_xp);
1b8be32e RP	173	break;
	174	}
	175
3a59684c BG	176	/* 1 ... coordinate_readouts is for Y */
3a59684c BG	177	end_step = first_step + ts_dev->coordinate_readouts;
23dee6c6	178	n = 0;
3a59684c	179	for (i = first_step; i < end_step; i++) {
55c04de5	180	titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
23dee6c6 DB	181	titsc_writel(ts_dev, REG_STEPDELAY(i),
23dee6c6 DB	182	n++ == 0 ? STEPCONFIG_OPENDLY : 0);
1b8be32e RP	183	}
1b8be32e RP	184
344d635b	185	/* Make CHARGECONFIG same as IDLECONFIG */
1b8be32e	186
344d635b	187	config = titsc_readl(ts_dev, REG_IDLECONFIG);
55c04de5	188	titsc_writel(ts_dev, REG_CHARGECONFIG, config);
bf223612	189	titsc_writel(ts_dev, REG_CHARGEDELAY, ts_dev->charge_delay);
1b8be32e	190
3a59684c	191	/* coordinate_readouts + 1 ... coordinate_readouts + 2 is for Z */
1b8be32e	192	config = STEPCONFIG_MODE_HWSYNC \|
bb76dc09 PR	193	STEPCONFIG_AVG_16 \| ts_dev->bit_yp \|
	194	ts_dev->bit_xn \| STEPCONFIG_INM_ADCREFM \|
	195	STEPCONFIG_INP(ts_dev->inp_xp);
8c896308 SAS	196	titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
8c896308 SAS	197	titsc_writel(ts_dev, REG_STEPDELAY(end_step),
d1fb5743	198	STEPCONFIG_OPENDLY);
1b8be32e	199
8c896308	200	end_step++;
6bfeb6c2 DB	201	config = STEPCONFIG_MODE_HWSYNC \|
	202	STEPCONFIG_AVG_16 \| ts_dev->bit_yp \|
	203	ts_dev->bit_xn \| STEPCONFIG_INM_ADCREFM \|
	204	STEPCONFIG_INP(ts_dev->inp_yn);
8c896308 SAS	205	titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
8c896308 SAS	206	titsc_writel(ts_dev, REG_STEPDELAY(end_step),
d1fb5743	207	STEPCONFIG_OPENDLY);
1b8be32e	208
3a59684c BG	209	/* The steps end ... end - readouts * 2 + 2 and bit 0 for TS_Charge */
	210	stepenable = 1;
	211	for (i = 0; i < tsc_steps; i++)
	212	stepenable \|= 1 << (first_step + i + 1);
	213
baee5399	214	ts_dev->step_mask = stepenable;
7e170c6e	215	am335x_tsc_se_set_cache(ts_dev->mfd_tscadc, ts_dev->step_mask);
1b8be32e RP	216	}
1b8be32e RP	217
83edfdf3 V	218	static int titsc_cmp_coord(const void a, const void b)
	219	{
	220	return (int )a - (int )b;
	221	}
	222
55c04de5	223	static void titsc_read_coordinates(struct titsc *ts_dev,
8c896308	224	u32 x, u32 y, u32 z1, u32 z2)
1b8be32e	225	{
83edfdf3 V	226	unsigned int yvals[7], xvals[7];
83edfdf3 V	227	unsigned int i, xsum = 0, ysum = 0;
8c896308	228	unsigned int creads = ts_dev->coordinate_readouts;
1b8be32e	229
83edfdf3 V	230	for (i = 0; i < creads; i++) {
	231	yvals[i] = titsc_readl(ts_dev, REG_FIFO0);
	232	yvals[i] &= 0xfff;
	233	}
1b8be32e	234
83edfdf3 V	235	*z1 = titsc_readl(ts_dev, REG_FIFO0);
	236	*z1 &= 0xfff;
	237	*z2 = titsc_readl(ts_dev, REG_FIFO0);
	238	*z2 &= 0xfff;
3a59684c	239
83edfdf3 V	240	for (i = 0; i < creads; i++) {
	241	xvals[i] = titsc_readl(ts_dev, REG_FIFO0);
	242	xvals[i] &= 0xfff;
	243	}
3a59684c	244
83edfdf3 V	245	/*
	246	* If co-ordinates readouts is less than 4 then
	247	* report the average. In case of 4 or more
	248	* readouts, sort the co-ordinate samples, drop
	249	* min and max values and report the average of
	250	* remaining values.
	251	*/
	252	if (creads <= 3) {
	253	for (i = 0; i < creads; i++) {
	254	ysum += yvals[i];
	255	xsum += xvals[i];
1b8be32e	256	}
83edfdf3 V	257	ysum /= creads;
	258	xsum /= creads;
	259	} else {
	260	sort(yvals, creads, sizeof(unsigned int),
	261	titsc_cmp_coord, NULL);
	262	sort(xvals, creads, sizeof(unsigned int),
	263	titsc_cmp_coord, NULL);
	264	for (i = 1; i < creads - 1; i++) {
	265	ysum += yvals[i];
	266	xsum += xvals[i];
	267	}
	268	ysum /= creads - 2;
	269	xsum /= creads - 2;
1b8be32e	270	}
83edfdf3 V	271	*y = ysum;
83edfdf3 V	272	*x = xsum;
1b8be32e RP	273	}
1b8be32e RP	274
55c04de5	275	static irqreturn_t titsc_irq(int irq, void *dev)
1b8be32e	276	{
55c04de5	277	struct titsc *ts_dev = dev;
1b8be32e	278	struct input_dev *input_dev = ts_dev->input;
344d635b	279	unsigned int fsm, status, irqclr = 0;
1b8be32e RP	280	unsigned int x = 0, y = 0;
1b8be32e RP	281	unsigned int z1, z2, z;
1b8be32e	282
344d635b BG	283	status = titsc_readl(ts_dev, REG_RAWIRQSTATUS);
	284	if (status & IRQENB_HW_PEN) {
	285	ts_dev->pen_down = true;
344d635b	286	irqclr \|= IRQENB_HW_PEN;
333e07ec	287	pm_stay_awake(ts_dev->dev);
344d635b BG	288	}
	289
	290	if (status & IRQENB_PENUP) {
	291	fsm = titsc_readl(ts_dev, REG_ADCFSM);
	292	if (fsm == ADCFSM_STEPID) {
	293	ts_dev->pen_down = false;
	294	input_report_key(input_dev, BTN_TOUCH, 0);
	295	input_report_abs(input_dev, ABS_PRESSURE, 0);
	296	input_sync(input_dev);
333e07ec	297	pm_relax(ts_dev->dev);
344d635b BG	298	} else {
	299	ts_dev->pen_down = true;
	300	}
	301	irqclr \|= IRQENB_PENUP;
	302	}
	303
	304	if (status & IRQENB_EOS)
	305	irqclr \|= IRQENB_EOS;
	306
baee5399 ZL	307	/*
	308	* ADC and touchscreen share the IRQ line.
	309	* FIFO1 interrupts are used by ADC. Handle FIFO0 IRQs here only
	310	*/
30af55f9	311	if (status & IRQENB_FIFO0THRES) {
1b8be32e	312
8c896308	313	titsc_read_coordinates(ts_dev, &x, &y, &z1, &z2);
2b99bafa	314
1b8be32e RP	315	if (ts_dev->pen_down && z1 != 0 && z2 != 0) {
	316	/*
	317	* Calculate pressure using formula
	318	* Resistance(touch) = x plate resistance *
b6e43ddd	319	* x position/4096 * ((z2 / z1) - 1)
1b8be32e	320	*/
8c896308	321	z = z1 - z2;
1b8be32e RP	322	z *= x;
1b8be32e RP	323	z *= ts_dev->x_plate_resistance;
8c896308	324	z /= z2;
1b8be32e RP	325	z = (z + 2047) >> 12;
	326
	327	if (z <= MAX_12BIT) {
	328	input_report_abs(input_dev, ABS_X, x);
	329	input_report_abs(input_dev, ABS_Y, y);
	330	input_report_abs(input_dev, ABS_PRESSURE, z);
	331	input_report_key(input_dev, BTN_TOUCH, 1);
	332	input_sync(input_dev);
	333	}
	334	}
30af55f9	335	irqclr \|= IRQENB_FIFO0THRES;
1b8be32e	336	}
9a28b883 SAS	337	if (irqclr) {
9a28b883 SAS	338	titsc_writel(ts_dev, REG_IRQSTATUS, irqclr);
344d635b BG	339	if (status & IRQENB_EOS)
	340	am335x_tsc_se_set_cache(ts_dev->mfd_tscadc,
	341	ts_dev->step_mask);
9a28b883 SAS	342	return IRQ_HANDLED;
	343	}
	344	return IRQ_NONE;
1b8be32e RP	345	}
1b8be32e RP	346
0396310b PR	347	static int titsc_parse_dt(struct platform_device *pdev,
	348	struct titsc *ts_dev)
	349	{
	350	struct device_node *node = pdev->dev.of_node;
	351	int err;
	352
	353	if (!node)
	354	return -EINVAL;
	355
	356	err = of_property_read_u32(node, "ti,wires", &ts_dev->wires);
	357	if (err < 0)
	358	return err;
	359	switch (ts_dev->wires) {
	360	case 4:
	361	case 5:
	362	case 8:
	363	break;
	364	default:
	365	return -EINVAL;
	366	}
	367
	368	err = of_property_read_u32(node, "ti,x-plate-resistance",
	369	&ts_dev->x_plate_resistance);
	370	if (err < 0)
	371	return err;
	372
c9aeb249 FB	373	/*
	374	* Try with the new binding first. If it fails, try again with
	375	* bogus, miss-spelled version.
	376	*/
	377	err = of_property_read_u32(node, "ti,coordinate-readouts",
0396310b	378	&ts_dev->coordinate_readouts);
31972f6e FB	379	if (err < 0) {
31972f6e FB	380	dev_warn(&pdev->dev, "please use 'ti,coordinate-readouts' instead\n");
c9aeb249 FB	381	err = of_property_read_u32(node, "ti,coordiante-readouts",
c9aeb249 FB	382	&ts_dev->coordinate_readouts);
31972f6e FB	383	}
31972f6e FB	384
0396310b PR	385	if (err < 0)
	386	return err;
	387
83edfdf3 V	388	if (ts_dev->coordinate_readouts <= 0) {
	389	dev_warn(&pdev->dev,
	390	"invalid co-ordinate readouts, resetting it to 5\n");
	391	ts_dev->coordinate_readouts = 5;
	392	}
	393
bf223612 V	394	err = of_property_read_u32(node, "ti,charge-delay",
	395	&ts_dev->charge_delay);
	396	/*
	397	* If ti,charge-delay value is not specified, then use
	398	* CHARGEDLY_OPENDLY as the default value.
	399	*/
	400	if (err < 0) {
	401	ts_dev->charge_delay = CHARGEDLY_OPENDLY;
	402	dev_warn(&pdev->dev, "ti,charge-delay not specified\n");
	403	}
	404
0396310b PR	405	return of_property_read_u32_array(node, "ti,wire-config",
0396310b PR	406	ts_dev->config_inp, ARRAY_SIZE(ts_dev->config_inp));
1b8be32e RP	407	}
	408
	409	/*
	410	* The functions for inserting/removing driver as a module.
	411	*/
	412
31564cbd	413	static int titsc_probe(struct platform_device *pdev)
1b8be32e	414	{
55c04de5	415	struct titsc *ts_dev;
1b8be32e	416	struct input_dev *input_dev;
a9bce1b0	417	struct ti_tscadc_dev *tscadc_dev = ti_tscadc_dev_get(pdev);
1b8be32e	418	int err;
1b8be32e	419
1b8be32e	420	/* Allocate memory for device */
520d8267	421	ts_dev = kzalloc(sizeof(*ts_dev), GFP_KERNEL);
1b8be32e RP	422	input_dev = input_allocate_device();
	423	if (!ts_dev \|\| !input_dev) {
	424	dev_err(&pdev->dev, "failed to allocate memory.\n");
	425	err = -ENOMEM;
	426	goto err_free_mem;
	427	}
	428
2b99bafa PR	429	tscadc_dev->tsc = ts_dev;
2b99bafa PR	430	ts_dev->mfd_tscadc = tscadc_dev;
1b8be32e	431	ts_dev->input = input_dev;
2b99bafa	432	ts_dev->irq = tscadc_dev->irq;
333e07ec	433	ts_dev->dev = &pdev->dev;
0396310b	434
b9194fdf	435	err = titsc_parse_dt(pdev, ts_dev);
0396310b PR	436	if (err) {
	437	dev_err(&pdev->dev, "Could not find valid DT data.\n");
	438	goto err_free_mem;
	439	}
1b8be32e	440
55c04de5	441	err = request_irq(ts_dev->irq, titsc_irq,
baee5399	442	IRQF_SHARED, pdev->dev.driver->name, ts_dev);
1b8be32e RP	443	if (err) {
1b8be32e RP	444	dev_err(&pdev->dev, "failed to allocate irq.\n");
2b99bafa	445	goto err_free_mem;
1b8be32e	446	}
1b8be32e	447
333e07ec	448	device_init_wakeup(&pdev->dev, true);
7a39915b V	449	err = dev_pm_set_wake_irq(&pdev->dev, ts_dev->irq);
	450	if (err)
	451	dev_err(&pdev->dev, "irq wake enable failed.\n");
333e07ec	452
46850420	453	titsc_writel(ts_dev, REG_IRQSTATUS, TSC_IRQENB_MASK);
55c04de5	454	titsc_writel(ts_dev, REG_IRQENABLE, IRQENB_FIFO0THRES);
344d635b	455	titsc_writel(ts_dev, REG_IRQENABLE, IRQENB_EOS);
bb76dc09 PR	456	err = titsc_config_wires(ts_dev);
	457	if (err) {
	458	dev_err(&pdev->dev, "wrong i/p wire configuration\n");
	459	goto err_free_irq;
	460	}
55c04de5	461	titsc_step_config(ts_dev);
8c896308 SAS	462	titsc_writel(ts_dev, REG_FIFO0THR,
8c896308 SAS	463	ts_dev->coordinate_readouts * 2 + 2 - 1);
1b8be32e	464
2b99bafa	465	input_dev->name = "ti-tsc";
1b8be32e RP	466	input_dev->dev.parent = &pdev->dev;
	467
	468	input_dev->evbit[0] = BIT_MASK(EV_KEY) \| BIT_MASK(EV_ABS);
	469	input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
	470
	471	input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, 0, 0);
	472	input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0);
	473	input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT, 0, 0);
	474
	475	/* register to the input system */
	476	err = input_register_device(input_dev);
	477	if (err)
2b99bafa	478	goto err_free_irq;
1b8be32e RP	479
	480	platform_set_drvdata(pdev, ts_dev);
	481	return 0;
	482
1b8be32e	483	err_free_irq:
7a39915b	484	dev_pm_clear_wake_irq(&pdev->dev);
333e07ec	485	device_init_wakeup(&pdev->dev, false);
1b8be32e	486	free_irq(ts_dev->irq, ts_dev);
1b8be32e RP	487	err_free_mem:
	488	input_free_device(input_dev);
	489	kfree(ts_dev);
	490	return err;
	491	}
	492
d722a702	493	static void titsc_remove(struct platform_device *pdev)
1b8be32e	494	{
a9bce1b0 SAS	495	struct titsc *ts_dev = platform_get_drvdata(pdev);
a9bce1b0 SAS	496	u32 steps;
1b8be32e	497
7a39915b	498	dev_pm_clear_wake_irq(&pdev->dev);
333e07ec	499	device_init_wakeup(&pdev->dev, false);
1b8be32e RP	500	free_irq(ts_dev->irq, ts_dev);
1b8be32e RP	501
abeccee4	502	/* total steps followed by the enable mask */
0396310b	503	steps = 2 * ts_dev->coordinate_readouts + 2;
abeccee4 PR	504	steps = (1 << steps) - 1;
	505	am335x_tsc_se_clr(ts_dev->mfd_tscadc, steps);
	506
1b8be32e RP	507	input_unregister_device(ts_dev->input);
1b8be32e RP	508
2b99bafa	509	kfree(ts_dev);
2b99bafa	510	}
1b8be32e	511
f8401643	512	static int titsc_suspend(struct device *dev)
2b99bafa	513	{
a9bce1b0	514	struct titsc *ts_dev = dev_get_drvdata(dev);
2b99bafa PR	515	unsigned int idle;
2b99bafa PR	516
333e07ec	517	if (device_may_wakeup(dev)) {
46850420	518	titsc_writel(ts_dev, REG_IRQSTATUS, TSC_IRQENB_MASK);
2b99bafa PR	519	idle = titsc_readl(ts_dev, REG_IRQENABLE);
	520	titsc_writel(ts_dev, REG_IRQENABLE,
	521	(idle \| IRQENB_HW_PEN));
	522	titsc_writel(ts_dev, REG_IRQWAKEUP, IRQWKUP_ENB);
	523	}
	524	return 0;
	525	}
1b8be32e	526
f8401643	527	static int titsc_resume(struct device *dev)
2b99bafa	528	{
a9bce1b0	529	struct titsc *ts_dev = dev_get_drvdata(dev);
1b8be32e	530
333e07ec	531	if (device_may_wakeup(dev)) {
2b99bafa PR	532	titsc_writel(ts_dev, REG_IRQWAKEUP,
	533	0x00);
	534	titsc_writel(ts_dev, REG_IRQCLR, IRQENB_HW_PEN);
333e07ec	535	pm_relax(dev);
2b99bafa PR	536	}
	537	titsc_step_config(ts_dev);
	538	titsc_writel(ts_dev, REG_FIFO0THR,
8c896308	539	ts_dev->coordinate_readouts * 2 + 2 - 1);
1b8be32e RP	540	return 0;
	541	}
	542
f8401643	543	static DEFINE_SIMPLE_DEV_PM_OPS(titsc_pm_ops, titsc_suspend, titsc_resume);
2b99bafa	544
0396310b PR	545	static const struct of_device_id ti_tsc_dt_ids[] = {
	546	{ .compatible = "ti,am3359-tsc", },
	547	{ }
	548	};
	549	MODULE_DEVICE_TABLE(of, ti_tsc_dt_ids);
	550
1b8be32e	551	static struct platform_driver ti_tsc_driver = {
55c04de5	552	.probe = titsc_probe,
2c19d015	553	.remove = titsc_remove,
1b8be32e	554	.driver = {
2c19d015	555	.name = "TI-am335x-tsc",
f8401643	556	.pm = pm_sleep_ptr(&titsc_pm_ops),
8e6146bf	557	.of_match_table = ti_tsc_dt_ids,
1b8be32e RP	558	},
	559	};
	560	module_platform_driver(ti_tsc_driver);
	561
	562	MODULE_DESCRIPTION("TI touchscreen controller driver");
	563	MODULE_AUTHOR("Rachna Patil <rachna@ti.com>");
	564	MODULE_LICENSE("GPL");