[mirror_ubuntu-eoan-kernel.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)

#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;
	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 |
				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;
	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;
		irqclr |= IRQENB_HW_PEN;
		pm_stay_awake(ts_dev->mfd_tscadc->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->mfd_tscadc->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(*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;

	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_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:
	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;
}

static int __maybe_unused 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)) {
		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 __maybe_unused 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);
		pm_relax(ts_dev->mfd_tscadc->dev);
	}
	titsc_step_config(ts_dev);
	titsc_writel(ts_dev, REG_FIFO0THR,
			ts_dev->coordinate_readouts * 2 + 2 - 1);
	return 0;
}

static 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	= &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
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;
1b8be32e RP	49	unsigned int irq;
	50	unsigned int wires;
	51	unsigned int x_plate_resistance;
	52	bool pen_down;
0396310b	53	int coordinate_readouts;
bb76dc09 PR	54	u32 config_inp[4];
	55	u32 bit_xp, bit_xn, bit_yp, bit_yn;
	56	u32 inp_xp, inp_xn, inp_yp, inp_yn;
baee5399	57	u32 step_mask;
bf223612	58	u32 charge_delay;
1b8be32e RP	59	};
1b8be32e RP	60
55c04de5	61	static unsigned int titsc_readl(struct titsc *ts, unsigned int reg)
1b8be32e	62	{
2b99bafa	63	return readl(ts->mfd_tscadc->tscadc_base + reg);
1b8be32e RP	64	}
1b8be32e RP	65
55c04de5	66	static void titsc_writel(struct titsc *tsc, unsigned int reg,
1b8be32e RP	67	unsigned int val)
1b8be32e RP	68	{
2b99bafa	69	writel(val, tsc->mfd_tscadc->tscadc_base + reg);
1b8be32e RP	70	}
1b8be32e RP	71
bb76dc09 PR	72	static int titsc_config_wires(struct titsc *ts_dev)
	73	{
	74	u32 analog_line[4];
	75	u32 wire_order[4];
	76	int i, bit_cfg;
	77
	78	for (i = 0; i < 4; i++) {
	79	/*
	80	* Get the order in which TSC wires are attached
	81	* w.r.t. each of the analog input lines on the EVM.
	82	*/
	83	analog_line[i] = (ts_dev->config_inp[i] & 0xF0) >> 4;
	84	wire_order[i] = ts_dev->config_inp[i] & 0x0F;
	85	if (WARN_ON(analog_line[i] > 7))
	86	return -EINVAL;
	87	if (WARN_ON(wire_order[i] > ARRAY_SIZE(config_pins)))
	88	return -EINVAL;
	89	}
	90
	91	for (i = 0; i < 4; i++) {
	92	int an_line;
	93	int wi_order;
	94
	95	an_line = analog_line[i];
	96	wi_order = wire_order[i];
	97	bit_cfg = config_pins[wi_order];
	98	if (bit_cfg == 0)
	99	return -EINVAL;
	100	switch (wi_order) {
	101	case 0:
	102	ts_dev->bit_xp = bit_cfg;
	103	ts_dev->inp_xp = an_line;
	104	break;
	105
	106	case 1:
	107	ts_dev->bit_xn = bit_cfg;
	108	ts_dev->inp_xn = an_line;
	109	break;
	110
	111	case 2:
	112	ts_dev->bit_yp = bit_cfg;
	113	ts_dev->inp_yp = an_line;
	114	break;
	115	case 3:
	116	ts_dev->bit_yn = bit_cfg;
	117	ts_dev->inp_yn = an_line;
	118	break;
	119	}
	120	}
	121	return 0;
	122	}
	123
55c04de5	124	static void titsc_step_config(struct titsc *ts_dev)
1b8be32e RP	125	{
1b8be32e RP	126	unsigned int config;
8c896308	127	int i;
3a59684c	128	int end_step, first_step, tsc_steps;
8c896308	129	u32 stepenable;
1b8be32e RP	130
1b8be32e RP	131	config = STEPCONFIG_MODE_HWSYNC \|
bb76dc09	132	STEPCONFIG_AVG_16 \| ts_dev->bit_xp;
1b8be32e RP	133	switch (ts_dev->wires) {
1b8be32e RP	134	case 4:
bb76dc09	135	config \|= STEPCONFIG_INP(ts_dev->inp_yp) \| ts_dev->bit_xn;
1b8be32e RP	136	break;
1b8be32e RP	137	case 5:
bb76dc09 PR	138	config \|= ts_dev->bit_yn \|
	139	STEPCONFIG_INP_AN4 \| ts_dev->bit_xn \|
	140	ts_dev->bit_yp;
1b8be32e RP	141	break;
1b8be32e RP	142	case 8:
bb76dc09	143	config \|= STEPCONFIG_INP(ts_dev->inp_yp) \| ts_dev->bit_xn;
1b8be32e RP	144	break;
	145	}
	146
3a59684c BG	147	tsc_steps = ts_dev->coordinate_readouts * 2 + 2;
	148	first_step = TOTAL_STEPS - tsc_steps;
	149	/* Steps 16 to 16-coordinate_readouts is for X */
	150	end_step = first_step + tsc_steps;
	151	for (i = end_step - ts_dev->coordinate_readouts; i < end_step; i++) {
55c04de5 PR	152	titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
55c04de5 PR	153	titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
1b8be32e RP	154	}
	155
	156	config = 0;
	157	config = STEPCONFIG_MODE_HWSYNC \|
bb76dc09	158	STEPCONFIG_AVG_16 \| ts_dev->bit_yn \|
8c896308	159	STEPCONFIG_INM_ADCREFM;
1b8be32e RP	160	switch (ts_dev->wires) {
1b8be32e RP	161	case 4:
bb76dc09	162	config \|= ts_dev->bit_yp \| STEPCONFIG_INP(ts_dev->inp_xp);
1b8be32e RP	163	break;
1b8be32e RP	164	case 5:
bb76dc09	165	config \|= ts_dev->bit_xp \| STEPCONFIG_INP_AN4 \|
cf5dd489	166	STEPCONFIG_XNP \| STEPCONFIG_YPN;
1b8be32e RP	167	break;
1b8be32e RP	168	case 8:
bb76dc09	169	config \|= ts_dev->bit_yp \| STEPCONFIG_INP(ts_dev->inp_xp);
1b8be32e RP	170	break;
	171	}
	172
3a59684c BG	173	/* 1 ... coordinate_readouts is for Y */
	174	end_step = first_step + ts_dev->coordinate_readouts;
	175	for (i = first_step; i < end_step; i++) {
55c04de5 PR	176	titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
55c04de5 PR	177	titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
1b8be32e RP	178	}
1b8be32e RP	179
344d635b	180	/* Make CHARGECONFIG same as IDLECONFIG */
1b8be32e	181
344d635b	182	config = titsc_readl(ts_dev, REG_IDLECONFIG);
55c04de5	183	titsc_writel(ts_dev, REG_CHARGECONFIG, config);
bf223612	184	titsc_writel(ts_dev, REG_CHARGEDELAY, ts_dev->charge_delay);
1b8be32e	185
3a59684c	186	/* coordinate_readouts + 1 ... coordinate_readouts + 2 is for Z */
1b8be32e	187	config = STEPCONFIG_MODE_HWSYNC \|
bb76dc09 PR	188	STEPCONFIG_AVG_16 \| ts_dev->bit_yp \|
	189	ts_dev->bit_xn \| STEPCONFIG_INM_ADCREFM \|
	190	STEPCONFIG_INP(ts_dev->inp_xp);
8c896308 SAS	191	titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
8c896308 SAS	192	titsc_writel(ts_dev, REG_STEPDELAY(end_step),
d1fb5743	193	STEPCONFIG_OPENDLY);
1b8be32e	194
8c896308 SAS	195	end_step++;
	196	config \|= STEPCONFIG_INP(ts_dev->inp_yn);
	197	titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
	198	titsc_writel(ts_dev, REG_STEPDELAY(end_step),
d1fb5743	199	STEPCONFIG_OPENDLY);
1b8be32e	200
3a59684c BG	201	/* The steps end ... end - readouts * 2 + 2 and bit 0 for TS_Charge */
	202	stepenable = 1;
	203	for (i = 0; i < tsc_steps; i++)
	204	stepenable \|= 1 << (first_step + i + 1);
	205
baee5399	206	ts_dev->step_mask = stepenable;
7e170c6e	207	am335x_tsc_se_set_cache(ts_dev->mfd_tscadc, ts_dev->step_mask);
1b8be32e RP	208	}
1b8be32e RP	209
83edfdf3 V	210	static int titsc_cmp_coord(const void a, const void b)
	211	{
	212	return (int )a - (int )b;
	213	}
	214
55c04de5	215	static void titsc_read_coordinates(struct titsc *ts_dev,
8c896308	216	u32 x, u32 y, u32 z1, u32 z2)
1b8be32e	217	{
83edfdf3 V	218	unsigned int yvals[7], xvals[7];
83edfdf3 V	219	unsigned int i, xsum = 0, ysum = 0;
8c896308	220	unsigned int creads = ts_dev->coordinate_readouts;
1b8be32e	221
83edfdf3 V	222	for (i = 0; i < creads; i++) {
	223	yvals[i] = titsc_readl(ts_dev, REG_FIFO0);
	224	yvals[i] &= 0xfff;
	225	}
1b8be32e	226
83edfdf3 V	227	*z1 = titsc_readl(ts_dev, REG_FIFO0);
	228	*z1 &= 0xfff;
	229	*z2 = titsc_readl(ts_dev, REG_FIFO0);
	230	*z2 &= 0xfff;
3a59684c	231
83edfdf3 V	232	for (i = 0; i < creads; i++) {
	233	xvals[i] = titsc_readl(ts_dev, REG_FIFO0);
	234	xvals[i] &= 0xfff;
	235	}
3a59684c	236
83edfdf3 V	237	/*
	238	* If co-ordinates readouts is less than 4 then
	239	* report the average. In case of 4 or more
	240	* readouts, sort the co-ordinate samples, drop
	241	* min and max values and report the average of
	242	* remaining values.
	243	*/
	244	if (creads <= 3) {
	245	for (i = 0; i < creads; i++) {
	246	ysum += yvals[i];
	247	xsum += xvals[i];
1b8be32e	248	}
83edfdf3 V	249	ysum /= creads;
	250	xsum /= creads;
	251	} else {
	252	sort(yvals, creads, sizeof(unsigned int),
	253	titsc_cmp_coord, NULL);
	254	sort(xvals, creads, sizeof(unsigned int),
	255	titsc_cmp_coord, NULL);
	256	for (i = 1; i < creads - 1; i++) {
	257	ysum += yvals[i];
	258	xsum += xvals[i];
	259	}
	260	ysum /= creads - 2;
	261	xsum /= creads - 2;
1b8be32e	262	}
83edfdf3 V	263	*y = ysum;
83edfdf3 V	264	*x = xsum;
1b8be32e RP	265	}
1b8be32e RP	266
55c04de5	267	static irqreturn_t titsc_irq(int irq, void *dev)
1b8be32e	268	{
55c04de5	269	struct titsc *ts_dev = dev;
1b8be32e	270	struct input_dev *input_dev = ts_dev->input;
344d635b	271	unsigned int fsm, status, irqclr = 0;
1b8be32e RP	272	unsigned int x = 0, y = 0;
1b8be32e RP	273	unsigned int z1, z2, z;
1b8be32e	274
344d635b BG	275	status = titsc_readl(ts_dev, REG_RAWIRQSTATUS);
	276	if (status & IRQENB_HW_PEN) {
	277	ts_dev->pen_down = true;
344d635b	278	irqclr \|= IRQENB_HW_PEN;
22a844b8	279	pm_stay_awake(ts_dev->mfd_tscadc->dev);
344d635b BG	280	}
	281
	282	if (status & IRQENB_PENUP) {
	283	fsm = titsc_readl(ts_dev, REG_ADCFSM);
	284	if (fsm == ADCFSM_STEPID) {
	285	ts_dev->pen_down = false;
	286	input_report_key(input_dev, BTN_TOUCH, 0);
	287	input_report_abs(input_dev, ABS_PRESSURE, 0);
	288	input_sync(input_dev);
22a844b8	289	pm_relax(ts_dev->mfd_tscadc->dev);
344d635b BG	290	} else {
	291	ts_dev->pen_down = true;
	292	}
	293	irqclr \|= IRQENB_PENUP;
	294	}
	295
	296	if (status & IRQENB_EOS)
	297	irqclr \|= IRQENB_EOS;
	298
baee5399 ZL	299	/*
	300	* ADC and touchscreen share the IRQ line.
	301	* FIFO1 interrupts are used by ADC. Handle FIFO0 IRQs here only
	302	*/
30af55f9	303	if (status & IRQENB_FIFO0THRES) {
1b8be32e	304
8c896308	305	titsc_read_coordinates(ts_dev, &x, &y, &z1, &z2);
2b99bafa	306
1b8be32e RP	307	if (ts_dev->pen_down && z1 != 0 && z2 != 0) {
	308	/*
	309	* Calculate pressure using formula
	310	* Resistance(touch) = x plate resistance *
	311	* x postion/4096 * ((z2 / z1) - 1)
	312	*/
8c896308	313	z = z1 - z2;
1b8be32e RP	314	z *= x;
1b8be32e RP	315	z *= ts_dev->x_plate_resistance;
8c896308	316	z /= z2;
1b8be32e RP	317	z = (z + 2047) >> 12;
	318
	319	if (z <= MAX_12BIT) {
	320	input_report_abs(input_dev, ABS_X, x);
	321	input_report_abs(input_dev, ABS_Y, y);
	322	input_report_abs(input_dev, ABS_PRESSURE, z);
	323	input_report_key(input_dev, BTN_TOUCH, 1);
	324	input_sync(input_dev);
	325	}
	326	}
30af55f9	327	irqclr \|= IRQENB_FIFO0THRES;
1b8be32e	328	}
9a28b883 SAS	329	if (irqclr) {
9a28b883 SAS	330	titsc_writel(ts_dev, REG_IRQSTATUS, irqclr);
344d635b BG	331	if (status & IRQENB_EOS)
	332	am335x_tsc_se_set_cache(ts_dev->mfd_tscadc,
	333	ts_dev->step_mask);
9a28b883 SAS	334	return IRQ_HANDLED;
	335	}
	336	return IRQ_NONE;
1b8be32e RP	337	}
1b8be32e RP	338
0396310b PR	339	static int titsc_parse_dt(struct platform_device *pdev,
	340	struct titsc *ts_dev)
	341	{
	342	struct device_node *node = pdev->dev.of_node;
	343	int err;
	344
	345	if (!node)
	346	return -EINVAL;
	347
	348	err = of_property_read_u32(node, "ti,wires", &ts_dev->wires);
	349	if (err < 0)
	350	return err;
	351	switch (ts_dev->wires) {
	352	case 4:
	353	case 5:
	354	case 8:
	355	break;
	356	default:
	357	return -EINVAL;
	358	}
	359
	360	err = of_property_read_u32(node, "ti,x-plate-resistance",
	361	&ts_dev->x_plate_resistance);
	362	if (err < 0)
	363	return err;
	364
c9aeb249 FB	365	/*
	366	* Try with the new binding first. If it fails, try again with
	367	* bogus, miss-spelled version.
	368	*/
	369	err = of_property_read_u32(node, "ti,coordinate-readouts",
0396310b	370	&ts_dev->coordinate_readouts);
31972f6e FB	371	if (err < 0) {
31972f6e FB	372	dev_warn(&pdev->dev, "please use 'ti,coordinate-readouts' instead\n");
c9aeb249 FB	373	err = of_property_read_u32(node, "ti,coordiante-readouts",
c9aeb249 FB	374	&ts_dev->coordinate_readouts);
31972f6e FB	375	}
31972f6e FB	376
0396310b PR	377	if (err < 0)
	378	return err;
	379
83edfdf3 V	380	if (ts_dev->coordinate_readouts <= 0) {
	381	dev_warn(&pdev->dev,
	382	"invalid co-ordinate readouts, resetting it to 5\n");
	383	ts_dev->coordinate_readouts = 5;
	384	}
	385
bf223612 V	386	err = of_property_read_u32(node, "ti,charge-delay",
	387	&ts_dev->charge_delay);
	388	/*
	389	* If ti,charge-delay value is not specified, then use
	390	* CHARGEDLY_OPENDLY as the default value.
	391	*/
	392	if (err < 0) {
	393	ts_dev->charge_delay = CHARGEDLY_OPENDLY;
	394	dev_warn(&pdev->dev, "ti,charge-delay not specified\n");
	395	}
	396
0396310b PR	397	return of_property_read_u32_array(node, "ti,wire-config",
0396310b PR	398	ts_dev->config_inp, ARRAY_SIZE(ts_dev->config_inp));
1b8be32e RP	399	}
	400
	401	/*
	402	* The functions for inserting/removing driver as a module.
	403	*/
	404
31564cbd	405	static int titsc_probe(struct platform_device *pdev)
1b8be32e	406	{
55c04de5	407	struct titsc *ts_dev;
1b8be32e	408	struct input_dev *input_dev;
a9bce1b0	409	struct ti_tscadc_dev *tscadc_dev = ti_tscadc_dev_get(pdev);
1b8be32e	410	int err;
1b8be32e	411
1b8be32e	412	/* Allocate memory for device */
520d8267	413	ts_dev = kzalloc(sizeof(*ts_dev), GFP_KERNEL);
1b8be32e RP	414	input_dev = input_allocate_device();
	415	if (!ts_dev \|\| !input_dev) {
	416	dev_err(&pdev->dev, "failed to allocate memory.\n");
	417	err = -ENOMEM;
	418	goto err_free_mem;
	419	}
	420
2b99bafa PR	421	tscadc_dev->tsc = ts_dev;
2b99bafa PR	422	ts_dev->mfd_tscadc = tscadc_dev;
1b8be32e	423	ts_dev->input = input_dev;
2b99bafa	424	ts_dev->irq = tscadc_dev->irq;
0396310b	425
b9194fdf	426	err = titsc_parse_dt(pdev, ts_dev);
0396310b PR	427	if (err) {
	428	dev_err(&pdev->dev, "Could not find valid DT data.\n");
	429	goto err_free_mem;
	430	}
1b8be32e	431
55c04de5	432	err = request_irq(ts_dev->irq, titsc_irq,
baee5399	433	IRQF_SHARED, pdev->dev.driver->name, ts_dev);
1b8be32e RP	434	if (err) {
1b8be32e RP	435	dev_err(&pdev->dev, "failed to allocate irq.\n");
2b99bafa	436	goto err_free_mem;
1b8be32e	437	}
1b8be32e	438
46850420	439	titsc_writel(ts_dev, REG_IRQSTATUS, TSC_IRQENB_MASK);
55c04de5	440	titsc_writel(ts_dev, REG_IRQENABLE, IRQENB_FIFO0THRES);
344d635b	441	titsc_writel(ts_dev, REG_IRQENABLE, IRQENB_EOS);
bb76dc09 PR	442	err = titsc_config_wires(ts_dev);
	443	if (err) {
	444	dev_err(&pdev->dev, "wrong i/p wire configuration\n");
	445	goto err_free_irq;
	446	}
55c04de5	447	titsc_step_config(ts_dev);
8c896308 SAS	448	titsc_writel(ts_dev, REG_FIFO0THR,
8c896308 SAS	449	ts_dev->coordinate_readouts * 2 + 2 - 1);
1b8be32e	450
2b99bafa	451	input_dev->name = "ti-tsc";
1b8be32e RP	452	input_dev->dev.parent = &pdev->dev;
	453
	454	input_dev->evbit[0] = BIT_MASK(EV_KEY) \| BIT_MASK(EV_ABS);
	455	input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
	456
	457	input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, 0, 0);
	458	input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0);
	459	input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT, 0, 0);
	460
	461	/* register to the input system */
	462	err = input_register_device(input_dev);
	463	if (err)
2b99bafa	464	goto err_free_irq;
1b8be32e RP	465
	466	platform_set_drvdata(pdev, ts_dev);
	467	return 0;
	468
1b8be32e RP	469	err_free_irq:
1b8be32e RP	470	free_irq(ts_dev->irq, ts_dev);
1b8be32e RP	471	err_free_mem:
	472	input_free_device(input_dev);
	473	kfree(ts_dev);
	474	return err;
	475	}
	476
31564cbd	477	static int titsc_remove(struct platform_device *pdev)
1b8be32e	478	{
a9bce1b0 SAS	479	struct titsc *ts_dev = platform_get_drvdata(pdev);
a9bce1b0 SAS	480	u32 steps;
1b8be32e RP	481
	482	free_irq(ts_dev->irq, ts_dev);
	483
abeccee4	484	/* total steps followed by the enable mask */
0396310b	485	steps = 2 * ts_dev->coordinate_readouts + 2;
abeccee4 PR	486	steps = (1 << steps) - 1;
	487	am335x_tsc_se_clr(ts_dev->mfd_tscadc, steps);
	488
1b8be32e RP	489	input_unregister_device(ts_dev->input);
1b8be32e RP	490
2b99bafa PR	491	kfree(ts_dev);
	492	return 0;
	493	}
1b8be32e	494
20aa787e	495	static int __maybe_unused titsc_suspend(struct device *dev)
2b99bafa	496	{
a9bce1b0 SAS	497	struct titsc *ts_dev = dev_get_drvdata(dev);
a9bce1b0 SAS	498	struct ti_tscadc_dev *tscadc_dev;
2b99bafa PR	499	unsigned int idle;
2b99bafa PR	500
a9bce1b0	501	tscadc_dev = ti_tscadc_dev_get(to_platform_device(dev));
2b99bafa	502	if (device_may_wakeup(tscadc_dev->dev)) {
46850420	503	titsc_writel(ts_dev, REG_IRQSTATUS, TSC_IRQENB_MASK);
2b99bafa PR	504	idle = titsc_readl(ts_dev, REG_IRQENABLE);
	505	titsc_writel(ts_dev, REG_IRQENABLE,
	506	(idle \| IRQENB_HW_PEN));
	507	titsc_writel(ts_dev, REG_IRQWAKEUP, IRQWKUP_ENB);
	508	}
	509	return 0;
	510	}
1b8be32e	511
20aa787e	512	static int __maybe_unused titsc_resume(struct device *dev)
2b99bafa	513	{
a9bce1b0 SAS	514	struct titsc *ts_dev = dev_get_drvdata(dev);
a9bce1b0 SAS	515	struct ti_tscadc_dev *tscadc_dev;
1b8be32e	516
a9bce1b0	517	tscadc_dev = ti_tscadc_dev_get(to_platform_device(dev));
2b99bafa PR	518	if (device_may_wakeup(tscadc_dev->dev)) {
	519	titsc_writel(ts_dev, REG_IRQWAKEUP,
	520	0x00);
	521	titsc_writel(ts_dev, REG_IRQCLR, IRQENB_HW_PEN);
22a844b8	522	pm_relax(ts_dev->mfd_tscadc->dev);
2b99bafa PR	523	}
	524	titsc_step_config(ts_dev);
	525	titsc_writel(ts_dev, REG_FIFO0THR,
8c896308	526	ts_dev->coordinate_readouts * 2 + 2 - 1);
1b8be32e RP	527	return 0;
	528	}
	529
20aa787e	530	static SIMPLE_DEV_PM_OPS(titsc_pm_ops, titsc_suspend, titsc_resume);
2b99bafa	531
0396310b PR	532	static const struct of_device_id ti_tsc_dt_ids[] = {
	533	{ .compatible = "ti,am3359-tsc", },
	534	{ }
	535	};
	536	MODULE_DEVICE_TABLE(of, ti_tsc_dt_ids);
	537
1b8be32e	538	static struct platform_driver ti_tsc_driver = {
55c04de5	539	.probe = titsc_probe,
31564cbd	540	.remove = titsc_remove,
1b8be32e	541	.driver = {
5f184e63	542	.name = "TI-am335x-tsc",
20aa787e	543	.pm = &titsc_pm_ops,
8e6146bf	544	.of_match_table = ti_tsc_dt_ids,
1b8be32e RP	545	},
	546	};
	547	module_platform_driver(ti_tsc_driver);
	548
	549	MODULE_DESCRIPTION("TI touchscreen controller driver");
	550	MODULE_AUTHOR("Rachna Patil <rachna@ti.com>");
	551	MODULE_LICENSE("GPL");