[deliverable/linux.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/of_device.h>
#include <linux/sort.h>

#include <linux/mfd/ti_am335x_tscadc.h>

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

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;
	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;
	int end_step, first_step, tsc_steps;
	u32 stepenable;

	config = STEPCONFIG_MODE_HWSYNC |
			STEPCONFIG_AVG_16 | ts_dev->bit_xp;
	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;
	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), STEPCONFIG_OPENDLY);
	}

	config = 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 |
				ts_dev->bit_xn | ts_dev->bit_yp;
		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;
	for (i = first_step; i < end_step; i++) {
		titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
		titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
	}

	/* 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_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;
		titsc_writel(ts_dev, REG_IRQWAKEUP, 0x00);
		titsc_writel(ts_dev, REG_IRQCLR, IRQENB_HW_PEN);
		irqclr |= IRQENB_HW_PEN;
	}

	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);
		} 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 postion/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(struct titsc), 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;

	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;
	}

	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:
	free_irq(ts_dev->irq, ts_dev);
err_free_mem:
	input_free_device(input_dev);
	kfree(ts_dev);
	return err;
}

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

	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);
	return 0;
}

#ifdef CONFIG_PM
static int titsc_suspend(struct device *dev)
{
	struct titsc *ts_dev = dev_get_drvdata(dev);
	struct ti_tscadc_dev *tscadc_dev;
	unsigned int idle;

	tscadc_dev = ti_tscadc_dev_get(to_platform_device(dev));
	if (device_may_wakeup(tscadc_dev->dev)) {
		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);
	struct ti_tscadc_dev *tscadc_dev;

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

static const struct dev_pm_ops titsc_pm_ops = {
	.suspend = titsc_suspend,
	.resume  = titsc_resume,
};
#define TITSC_PM_OPS (&titsc_pm_ops)
#else
#define TITSC_PM_OPS NULL
#endif

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	= 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 PR	27	#include <linux/of.h>
0396310b PR	28	#include <linux/of_device.h>
83edfdf3	29	#include <linux/sort.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
bb76dc09 PR	37	static const int config_pins[] = {
	38	STEPCONFIG_XPP,
	39	STEPCONFIG_XNN,
	40	STEPCONFIG_YPP,
	41	STEPCONFIG_YNN,
	42	};
	43
55c04de5	44	struct titsc {
1b8be32e	45	struct input_dev *input;
2b99bafa	46	struct ti_tscadc_dev *mfd_tscadc;
1b8be32e RP	47	unsigned int irq;
	48	unsigned int wires;
	49	unsigned int x_plate_resistance;
	50	bool pen_down;
0396310b	51	int coordinate_readouts;
bb76dc09 PR	52	u32 config_inp[4];
	53	u32 bit_xp, bit_xn, bit_yp, bit_yn;
	54	u32 inp_xp, inp_xn, inp_yp, inp_yn;
baee5399	55	u32 step_mask;
bf223612	56	u32 charge_delay;
1b8be32e RP	57	};
1b8be32e RP	58
55c04de5	59	static unsigned int titsc_readl(struct titsc *ts, unsigned int reg)
1b8be32e	60	{
2b99bafa	61	return readl(ts->mfd_tscadc->tscadc_base + reg);
1b8be32e RP	62	}
1b8be32e RP	63
55c04de5	64	static void titsc_writel(struct titsc *tsc, unsigned int reg,
1b8be32e RP	65	unsigned int val)
1b8be32e RP	66	{
2b99bafa	67	writel(val, tsc->mfd_tscadc->tscadc_base + reg);
1b8be32e RP	68	}
1b8be32e RP	69
bb76dc09 PR	70	static int titsc_config_wires(struct titsc *ts_dev)
	71	{
	72	u32 analog_line[4];
	73	u32 wire_order[4];
	74	int i, bit_cfg;
	75
	76	for (i = 0; i < 4; i++) {
	77	/*
	78	* Get the order in which TSC wires are attached
	79	* w.r.t. each of the analog input lines on the EVM.
	80	*/
	81	analog_line[i] = (ts_dev->config_inp[i] & 0xF0) >> 4;
	82	wire_order[i] = ts_dev->config_inp[i] & 0x0F;
	83	if (WARN_ON(analog_line[i] > 7))
	84	return -EINVAL;
	85	if (WARN_ON(wire_order[i] > ARRAY_SIZE(config_pins)))
	86	return -EINVAL;
	87	}
	88
	89	for (i = 0; i < 4; i++) {
	90	int an_line;
	91	int wi_order;
	92
	93	an_line = analog_line[i];
	94	wi_order = wire_order[i];
	95	bit_cfg = config_pins[wi_order];
	96	if (bit_cfg == 0)
	97	return -EINVAL;
	98	switch (wi_order) {
	99	case 0:
	100	ts_dev->bit_xp = bit_cfg;
	101	ts_dev->inp_xp = an_line;
	102	break;
	103
	104	case 1:
	105	ts_dev->bit_xn = bit_cfg;
	106	ts_dev->inp_xn = an_line;
	107	break;
	108
	109	case 2:
	110	ts_dev->bit_yp = bit_cfg;
	111	ts_dev->inp_yp = an_line;
	112	break;
	113	case 3:
	114	ts_dev->bit_yn = bit_cfg;
	115	ts_dev->inp_yn = an_line;
	116	break;
	117	}
	118	}
	119	return 0;
	120	}
	121
55c04de5	122	static void titsc_step_config(struct titsc *ts_dev)
1b8be32e RP	123	{
1b8be32e RP	124	unsigned int config;
8c896308	125	int i;
3a59684c	126	int end_step, first_step, tsc_steps;
8c896308	127	u32 stepenable;
1b8be32e RP	128
1b8be32e RP	129	config = STEPCONFIG_MODE_HWSYNC \|
bb76dc09	130	STEPCONFIG_AVG_16 \| ts_dev->bit_xp;
1b8be32e RP	131	switch (ts_dev->wires) {
1b8be32e RP	132	case 4:
bb76dc09	133	config \|= STEPCONFIG_INP(ts_dev->inp_yp) \| ts_dev->bit_xn;
1b8be32e RP	134	break;
1b8be32e RP	135	case 5:
bb76dc09 PR	136	config \|= ts_dev->bit_yn \|
	137	STEPCONFIG_INP_AN4 \| ts_dev->bit_xn \|
	138	ts_dev->bit_yp;
1b8be32e RP	139	break;
1b8be32e RP	140	case 8:
bb76dc09	141	config \|= STEPCONFIG_INP(ts_dev->inp_yp) \| ts_dev->bit_xn;
1b8be32e RP	142	break;
	143	}
	144
3a59684c BG	145	tsc_steps = ts_dev->coordinate_readouts * 2 + 2;
	146	first_step = TOTAL_STEPS - tsc_steps;
	147	/* Steps 16 to 16-coordinate_readouts is for X */
	148	end_step = first_step + tsc_steps;
	149	for (i = end_step - ts_dev->coordinate_readouts; i < end_step; i++) {
55c04de5 PR	150	titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
55c04de5 PR	151	titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
1b8be32e RP	152	}
	153
	154	config = 0;
	155	config = STEPCONFIG_MODE_HWSYNC \|
bb76dc09	156	STEPCONFIG_AVG_16 \| ts_dev->bit_yn \|
8c896308	157	STEPCONFIG_INM_ADCREFM;
1b8be32e RP	158	switch (ts_dev->wires) {
1b8be32e RP	159	case 4:
bb76dc09	160	config \|= ts_dev->bit_yp \| STEPCONFIG_INP(ts_dev->inp_xp);
1b8be32e RP	161	break;
1b8be32e RP	162	case 5:
bb76dc09 PR	163	config \|= ts_dev->bit_xp \| STEPCONFIG_INP_AN4 \|
bb76dc09 PR	164	ts_dev->bit_xn \| ts_dev->bit_yp;
1b8be32e RP	165	break;
1b8be32e RP	166	case 8:
bb76dc09	167	config \|= ts_dev->bit_yp \| STEPCONFIG_INP(ts_dev->inp_xp);
1b8be32e RP	168	break;
	169	}
	170
3a59684c BG	171	/* 1 ... coordinate_readouts is for Y */
	172	end_step = first_step + ts_dev->coordinate_readouts;
	173	for (i = first_step; i < end_step; i++) {
55c04de5 PR	174	titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
55c04de5 PR	175	titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
1b8be32e RP	176	}
1b8be32e RP	177
344d635b	178	/* Make CHARGECONFIG same as IDLECONFIG */
1b8be32e	179
344d635b	180	config = titsc_readl(ts_dev, REG_IDLECONFIG);
55c04de5	181	titsc_writel(ts_dev, REG_CHARGECONFIG, config);
bf223612	182	titsc_writel(ts_dev, REG_CHARGEDELAY, ts_dev->charge_delay);
1b8be32e	183
3a59684c	184	/* coordinate_readouts + 1 ... coordinate_readouts + 2 is for Z */
1b8be32e	185	config = STEPCONFIG_MODE_HWSYNC \|
bb76dc09 PR	186	STEPCONFIG_AVG_16 \| ts_dev->bit_yp \|
	187	ts_dev->bit_xn \| STEPCONFIG_INM_ADCREFM \|
	188	STEPCONFIG_INP(ts_dev->inp_xp);
8c896308 SAS	189	titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
8c896308 SAS	190	titsc_writel(ts_dev, REG_STEPDELAY(end_step),
d1fb5743	191	STEPCONFIG_OPENDLY);
1b8be32e	192
8c896308 SAS	193	end_step++;
	194	config \|= STEPCONFIG_INP(ts_dev->inp_yn);
	195	titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
	196	titsc_writel(ts_dev, REG_STEPDELAY(end_step),
d1fb5743	197	STEPCONFIG_OPENDLY);
1b8be32e	198
3a59684c BG	199	/* The steps end ... end - readouts * 2 + 2 and bit 0 for TS_Charge */
	200	stepenable = 1;
	201	for (i = 0; i < tsc_steps; i++)
	202	stepenable \|= 1 << (first_step + i + 1);
	203
baee5399	204	ts_dev->step_mask = stepenable;
7e170c6e	205	am335x_tsc_se_set_cache(ts_dev->mfd_tscadc, ts_dev->step_mask);
1b8be32e RP	206	}
1b8be32e RP	207
83edfdf3 V	208	static int titsc_cmp_coord(const void a, const void b)
	209	{
	210	return (int )a - (int )b;
	211	}
	212
55c04de5	213	static void titsc_read_coordinates(struct titsc *ts_dev,
8c896308	214	u32 x, u32 y, u32 z1, u32 z2)
1b8be32e	215	{
83edfdf3 V	216	unsigned int yvals[7], xvals[7];
83edfdf3 V	217	unsigned int i, xsum = 0, ysum = 0;
8c896308	218	unsigned int creads = ts_dev->coordinate_readouts;
1b8be32e	219
83edfdf3 V	220	for (i = 0; i < creads; i++) {
	221	yvals[i] = titsc_readl(ts_dev, REG_FIFO0);
	222	yvals[i] &= 0xfff;
	223	}
1b8be32e	224
83edfdf3 V	225	*z1 = titsc_readl(ts_dev, REG_FIFO0);
	226	*z1 &= 0xfff;
	227	*z2 = titsc_readl(ts_dev, REG_FIFO0);
	228	*z2 &= 0xfff;
3a59684c	229
83edfdf3 V	230	for (i = 0; i < creads; i++) {
	231	xvals[i] = titsc_readl(ts_dev, REG_FIFO0);
	232	xvals[i] &= 0xfff;
	233	}
3a59684c	234
83edfdf3 V	235	/*
	236	* If co-ordinates readouts is less than 4 then
	237	* report the average. In case of 4 or more
	238	* readouts, sort the co-ordinate samples, drop
	239	* min and max values and report the average of
	240	* remaining values.
	241	*/
	242	if (creads <= 3) {
	243	for (i = 0; i < creads; i++) {
	244	ysum += yvals[i];
	245	xsum += xvals[i];
1b8be32e	246	}
83edfdf3 V	247	ysum /= creads;
	248	xsum /= creads;
	249	} else {
	250	sort(yvals, creads, sizeof(unsigned int),
	251	titsc_cmp_coord, NULL);
	252	sort(xvals, creads, sizeof(unsigned int),
	253	titsc_cmp_coord, NULL);
	254	for (i = 1; i < creads - 1; i++) {
	255	ysum += yvals[i];
	256	xsum += xvals[i];
	257	}
	258	ysum /= creads - 2;
	259	xsum /= creads - 2;
1b8be32e	260	}
83edfdf3 V	261	*y = ysum;
83edfdf3 V	262	*x = xsum;
1b8be32e RP	263	}
1b8be32e RP	264
55c04de5	265	static irqreturn_t titsc_irq(int irq, void *dev)
1b8be32e	266	{
55c04de5	267	struct titsc *ts_dev = dev;
1b8be32e	268	struct input_dev *input_dev = ts_dev->input;
344d635b	269	unsigned int fsm, status, irqclr = 0;
1b8be32e RP	270	unsigned int x = 0, y = 0;
1b8be32e RP	271	unsigned int z1, z2, z;
1b8be32e	272
344d635b BG	273	status = titsc_readl(ts_dev, REG_RAWIRQSTATUS);
	274	if (status & IRQENB_HW_PEN) {
	275	ts_dev->pen_down = true;
	276	titsc_writel(ts_dev, REG_IRQWAKEUP, 0x00);
	277	titsc_writel(ts_dev, REG_IRQCLR, IRQENB_HW_PEN);
	278	irqclr \|= IRQENB_HW_PEN;
	279	}
	280
	281	if (status & IRQENB_PENUP) {
	282	fsm = titsc_readl(ts_dev, REG_ADCFSM);
	283	if (fsm == ADCFSM_STEPID) {
	284	ts_dev->pen_down = false;
	285	input_report_key(input_dev, BTN_TOUCH, 0);
	286	input_report_abs(input_dev, ABS_PRESSURE, 0);
	287	input_sync(input_dev);
	288	} else {
	289	ts_dev->pen_down = true;
	290	}
	291	irqclr \|= IRQENB_PENUP;
	292	}
	293
	294	if (status & IRQENB_EOS)
	295	irqclr \|= IRQENB_EOS;
	296
baee5399 ZL	297	/*
	298	* ADC and touchscreen share the IRQ line.
	299	* FIFO1 interrupts are used by ADC. Handle FIFO0 IRQs here only
	300	*/
30af55f9	301	if (status & IRQENB_FIFO0THRES) {
1b8be32e	302
8c896308	303	titsc_read_coordinates(ts_dev, &x, &y, &z1, &z2);
2b99bafa	304
1b8be32e RP	305	if (ts_dev->pen_down && z1 != 0 && z2 != 0) {
	306	/*
	307	* Calculate pressure using formula
	308	* Resistance(touch) = x plate resistance *
	309	* x postion/4096 * ((z2 / z1) - 1)
	310	*/
8c896308	311	z = z1 - z2;
1b8be32e RP	312	z *= x;
1b8be32e RP	313	z *= ts_dev->x_plate_resistance;
8c896308	314	z /= z2;
1b8be32e RP	315	z = (z + 2047) >> 12;
	316
	317	if (z <= MAX_12BIT) {
	318	input_report_abs(input_dev, ABS_X, x);
	319	input_report_abs(input_dev, ABS_Y, y);
	320	input_report_abs(input_dev, ABS_PRESSURE, z);
	321	input_report_key(input_dev, BTN_TOUCH, 1);
	322	input_sync(input_dev);
	323	}
	324	}
30af55f9	325	irqclr \|= IRQENB_FIFO0THRES;
1b8be32e	326	}
9a28b883 SAS	327	if (irqclr) {
9a28b883 SAS	328	titsc_writel(ts_dev, REG_IRQSTATUS, irqclr);
344d635b BG	329	if (status & IRQENB_EOS)
	330	am335x_tsc_se_set_cache(ts_dev->mfd_tscadc,
	331	ts_dev->step_mask);
9a28b883 SAS	332	return IRQ_HANDLED;
	333	}
	334	return IRQ_NONE;
1b8be32e RP	335	}
1b8be32e RP	336
0396310b PR	337	static int titsc_parse_dt(struct platform_device *pdev,
	338	struct titsc *ts_dev)
	339	{
	340	struct device_node *node = pdev->dev.of_node;
	341	int err;
	342
	343	if (!node)
	344	return -EINVAL;
	345
	346	err = of_property_read_u32(node, "ti,wires", &ts_dev->wires);
	347	if (err < 0)
	348	return err;
	349	switch (ts_dev->wires) {
	350	case 4:
	351	case 5:
	352	case 8:
	353	break;
	354	default:
	355	return -EINVAL;
	356	}
	357
	358	err = of_property_read_u32(node, "ti,x-plate-resistance",
	359	&ts_dev->x_plate_resistance);
	360	if (err < 0)
	361	return err;
	362
c9aeb249 FB	363	/*
	364	* Try with the new binding first. If it fails, try again with
	365	* bogus, miss-spelled version.
	366	*/
	367	err = of_property_read_u32(node, "ti,coordinate-readouts",
0396310b	368	&ts_dev->coordinate_readouts);
31972f6e FB	369	if (err < 0) {
31972f6e FB	370	dev_warn(&pdev->dev, "please use 'ti,coordinate-readouts' instead\n");
c9aeb249 FB	371	err = of_property_read_u32(node, "ti,coordiante-readouts",
c9aeb249 FB	372	&ts_dev->coordinate_readouts);
31972f6e FB	373	}
31972f6e FB	374
0396310b PR	375	if (err < 0)
	376	return err;
	377
83edfdf3 V	378	if (ts_dev->coordinate_readouts <= 0) {
	379	dev_warn(&pdev->dev,
	380	"invalid co-ordinate readouts, resetting it to 5\n");
	381	ts_dev->coordinate_readouts = 5;
	382	}
	383
bf223612 V	384	err = of_property_read_u32(node, "ti,charge-delay",
	385	&ts_dev->charge_delay);
	386	/*
	387	* If ti,charge-delay value is not specified, then use
	388	* CHARGEDLY_OPENDLY as the default value.
	389	*/
	390	if (err < 0) {
	391	ts_dev->charge_delay = CHARGEDLY_OPENDLY;
	392	dev_warn(&pdev->dev, "ti,charge-delay not specified\n");
	393	}
	394
0396310b PR	395	return of_property_read_u32_array(node, "ti,wire-config",
0396310b PR	396	ts_dev->config_inp, ARRAY_SIZE(ts_dev->config_inp));
1b8be32e RP	397	}
	398
	399	/*
	400	* The functions for inserting/removing driver as a module.
	401	*/
	402
31564cbd	403	static int titsc_probe(struct platform_device *pdev)
1b8be32e	404	{
55c04de5	405	struct titsc *ts_dev;
1b8be32e	406	struct input_dev *input_dev;
a9bce1b0	407	struct ti_tscadc_dev *tscadc_dev = ti_tscadc_dev_get(pdev);
1b8be32e	408	int err;
1b8be32e	409
1b8be32e	410	/* Allocate memory for device */
55c04de5	411	ts_dev = kzalloc(sizeof(struct titsc), GFP_KERNEL);
1b8be32e RP	412	input_dev = input_allocate_device();
	413	if (!ts_dev \|\| !input_dev) {
	414	dev_err(&pdev->dev, "failed to allocate memory.\n");
	415	err = -ENOMEM;
	416	goto err_free_mem;
	417	}
	418
2b99bafa PR	419	tscadc_dev->tsc = ts_dev;
2b99bafa PR	420	ts_dev->mfd_tscadc = tscadc_dev;
1b8be32e	421	ts_dev->input = input_dev;
2b99bafa	422	ts_dev->irq = tscadc_dev->irq;
0396310b	423
b9194fdf	424	err = titsc_parse_dt(pdev, ts_dev);
0396310b PR	425	if (err) {
	426	dev_err(&pdev->dev, "Could not find valid DT data.\n");
	427	goto err_free_mem;
	428	}
1b8be32e	429
55c04de5	430	err = request_irq(ts_dev->irq, titsc_irq,
baee5399	431	IRQF_SHARED, pdev->dev.driver->name, ts_dev);
1b8be32e RP	432	if (err) {
1b8be32e RP	433	dev_err(&pdev->dev, "failed to allocate irq.\n");
2b99bafa	434	goto err_free_mem;
1b8be32e	435	}
1b8be32e	436
55c04de5	437	titsc_writel(ts_dev, REG_IRQENABLE, IRQENB_FIFO0THRES);
344d635b	438	titsc_writel(ts_dev, REG_IRQENABLE, IRQENB_EOS);
bb76dc09 PR	439	err = titsc_config_wires(ts_dev);
	440	if (err) {
	441	dev_err(&pdev->dev, "wrong i/p wire configuration\n");
	442	goto err_free_irq;
	443	}
55c04de5	444	titsc_step_config(ts_dev);
8c896308 SAS	445	titsc_writel(ts_dev, REG_FIFO0THR,
8c896308 SAS	446	ts_dev->coordinate_readouts * 2 + 2 - 1);
1b8be32e	447
2b99bafa	448	input_dev->name = "ti-tsc";
1b8be32e RP	449	input_dev->dev.parent = &pdev->dev;
	450
	451	input_dev->evbit[0] = BIT_MASK(EV_KEY) \| BIT_MASK(EV_ABS);
	452	input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
	453
	454	input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, 0, 0);
	455	input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0);
	456	input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT, 0, 0);
	457
	458	/* register to the input system */
	459	err = input_register_device(input_dev);
	460	if (err)
2b99bafa	461	goto err_free_irq;
1b8be32e RP	462
	463	platform_set_drvdata(pdev, ts_dev);
	464	return 0;
	465
1b8be32e RP	466	err_free_irq:
1b8be32e RP	467	free_irq(ts_dev->irq, ts_dev);
1b8be32e RP	468	err_free_mem:
	469	input_free_device(input_dev);
	470	kfree(ts_dev);
	471	return err;
	472	}
	473
31564cbd	474	static int titsc_remove(struct platform_device *pdev)
1b8be32e	475	{
a9bce1b0 SAS	476	struct titsc *ts_dev = platform_get_drvdata(pdev);
a9bce1b0 SAS	477	u32 steps;
1b8be32e RP	478
	479	free_irq(ts_dev->irq, ts_dev);
	480
abeccee4	481	/* total steps followed by the enable mask */
0396310b	482	steps = 2 * ts_dev->coordinate_readouts + 2;
abeccee4 PR	483	steps = (1 << steps) - 1;
	484	am335x_tsc_se_clr(ts_dev->mfd_tscadc, steps);
	485
1b8be32e RP	486	input_unregister_device(ts_dev->input);
1b8be32e RP	487
2b99bafa PR	488	kfree(ts_dev);
	489	return 0;
	490	}
1b8be32e	491
2b99bafa PR	492	#ifdef CONFIG_PM
	493	static int titsc_suspend(struct device *dev)
	494	{
a9bce1b0 SAS	495	struct titsc *ts_dev = dev_get_drvdata(dev);
a9bce1b0 SAS	496	struct ti_tscadc_dev *tscadc_dev;
2b99bafa PR	497	unsigned int idle;
2b99bafa PR	498
a9bce1b0	499	tscadc_dev = ti_tscadc_dev_get(to_platform_device(dev));
2b99bafa PR	500	if (device_may_wakeup(tscadc_dev->dev)) {
	501	idle = titsc_readl(ts_dev, REG_IRQENABLE);
	502	titsc_writel(ts_dev, REG_IRQENABLE,
	503	(idle \| IRQENB_HW_PEN));
	504	titsc_writel(ts_dev, REG_IRQWAKEUP, IRQWKUP_ENB);
	505	}
	506	return 0;
	507	}
1b8be32e	508
2b99bafa PR	509	static int titsc_resume(struct device *dev)
2b99bafa PR	510	{
a9bce1b0 SAS	511	struct titsc *ts_dev = dev_get_drvdata(dev);
a9bce1b0 SAS	512	struct ti_tscadc_dev *tscadc_dev;
1b8be32e	513
a9bce1b0	514	tscadc_dev = ti_tscadc_dev_get(to_platform_device(dev));
2b99bafa PR	515	if (device_may_wakeup(tscadc_dev->dev)) {
	516	titsc_writel(ts_dev, REG_IRQWAKEUP,
	517	0x00);
	518	titsc_writel(ts_dev, REG_IRQCLR, IRQENB_HW_PEN);
	519	}
	520	titsc_step_config(ts_dev);
	521	titsc_writel(ts_dev, REG_FIFO0THR,
8c896308	522	ts_dev->coordinate_readouts * 2 + 2 - 1);
1b8be32e RP	523	return 0;
	524	}
	525
2b99bafa PR	526	static const struct dev_pm_ops titsc_pm_ops = {
	527	.suspend = titsc_suspend,
	528	.resume = titsc_resume,
	529	};
	530	#define TITSC_PM_OPS (&titsc_pm_ops)
	531	#else
	532	#define TITSC_PM_OPS NULL
	533	#endif
	534
0396310b PR	535	static const struct of_device_id ti_tsc_dt_ids[] = {
	536	{ .compatible = "ti,am3359-tsc", },
	537	{ }
	538	};
	539	MODULE_DEVICE_TABLE(of, ti_tsc_dt_ids);
	540
1b8be32e	541	static struct platform_driver ti_tsc_driver = {
55c04de5	542	.probe = titsc_probe,
31564cbd	543	.remove = titsc_remove,
1b8be32e	544	.driver = {
5f184e63	545	.name = "TI-am335x-tsc",
2b99bafa	546	.pm = TITSC_PM_OPS,
8e6146bf	547	.of_match_table = ti_tsc_dt_ids,
1b8be32e RP	548	},
	549	};
	550	module_platform_driver(ti_tsc_driver);
	551
	552	MODULE_DESCRIPTION("TI touchscreen controller driver");
	553	MODULE_AUTHOR("Rachna Patil <rachna@ti.com>");
	554	MODULE_LICENSE("GPL");