| /* | 
 |  * Touchscreen driver for Dialog Semiconductor DA9034 | 
 |  * | 
 |  * Copyright (C) 2006-2008 Marvell International Ltd. | 
 |  *	Fengwei Yin <fengwei.yin@marvell.com> | 
 |  *	Bin Yang  <bin.yang@marvell.com> | 
 |  *	Eric Miao <eric.miao@marvell.com> | 
 |  * | 
 |  * This program is free software; you can redistribute it and/or modify | 
 |  * it under the terms of the GNU General Public License version 2 as | 
 |  * published by the Free Software Foundation. | 
 |  */ | 
 |  | 
 | #include <linux/module.h> | 
 | #include <linux/kernel.h> | 
 | #include <linux/delay.h> | 
 | #include <linux/platform_device.h> | 
 | #include <linux/input.h> | 
 | #include <linux/workqueue.h> | 
 | #include <linux/mfd/da903x.h> | 
 | #include <linux/slab.h> | 
 |  | 
 | #define DA9034_MANUAL_CTRL	0x50 | 
 | #define DA9034_LDO_ADC_EN	(1 << 4) | 
 |  | 
 | #define DA9034_AUTO_CTRL1	0x51 | 
 |  | 
 | #define DA9034_AUTO_CTRL2	0x52 | 
 | #define DA9034_AUTO_TSI_EN	(1 << 3) | 
 | #define DA9034_PEN_DETECT	(1 << 4) | 
 |  | 
 | #define DA9034_TSI_CTRL1	0x53 | 
 | #define DA9034_TSI_CTRL2	0x54 | 
 | #define DA9034_TSI_X_MSB	0x6c | 
 | #define DA9034_TSI_Y_MSB	0x6d | 
 | #define DA9034_TSI_XY_LSB	0x6e | 
 |  | 
 | enum { | 
 | 	STATE_IDLE,	/* wait for pendown */ | 
 | 	STATE_BUSY,	/* TSI busy sampling */ | 
 | 	STATE_STOP,	/* sample available */ | 
 | 	STATE_WAIT,	/* Wait to start next sample */ | 
 | }; | 
 |  | 
 | enum { | 
 | 	EVENT_PEN_DOWN, | 
 | 	EVENT_PEN_UP, | 
 | 	EVENT_TSI_READY, | 
 | 	EVENT_TIMEDOUT, | 
 | }; | 
 |  | 
 | struct da9034_touch { | 
 | 	struct device		*da9034_dev; | 
 | 	struct input_dev	*input_dev; | 
 |  | 
 | 	struct delayed_work	tsi_work; | 
 | 	struct notifier_block	notifier; | 
 |  | 
 | 	int	state; | 
 |  | 
 | 	int	interval_ms; | 
 | 	int	x_inverted; | 
 | 	int	y_inverted; | 
 |  | 
 | 	int	last_x; | 
 | 	int	last_y; | 
 | }; | 
 |  | 
 | static inline int is_pen_down(struct da9034_touch *touch) | 
 | { | 
 | 	return da903x_query_status(touch->da9034_dev, DA9034_STATUS_PEN_DOWN); | 
 | } | 
 |  | 
 | static inline int detect_pen_down(struct da9034_touch *touch, int on) | 
 | { | 
 | 	if (on) | 
 | 		return da903x_set_bits(touch->da9034_dev, | 
 | 				DA9034_AUTO_CTRL2, DA9034_PEN_DETECT); | 
 | 	else | 
 | 		return da903x_clr_bits(touch->da9034_dev, | 
 | 				DA9034_AUTO_CTRL2, DA9034_PEN_DETECT); | 
 | } | 
 |  | 
 | static int read_tsi(struct da9034_touch *touch) | 
 | { | 
 | 	uint8_t _x, _y, _v; | 
 | 	int ret; | 
 |  | 
 | 	ret = da903x_read(touch->da9034_dev, DA9034_TSI_X_MSB, &_x); | 
 | 	if (ret) | 
 | 		return ret; | 
 |  | 
 | 	ret = da903x_read(touch->da9034_dev, DA9034_TSI_Y_MSB, &_y); | 
 | 	if (ret) | 
 | 		return ret; | 
 |  | 
 | 	ret = da903x_read(touch->da9034_dev, DA9034_TSI_XY_LSB, &_v); | 
 | 	if (ret) | 
 | 		return ret; | 
 |  | 
 | 	touch->last_x = ((_x << 2) & 0x3fc) | (_v & 0x3); | 
 | 	touch->last_y = ((_y << 2) & 0x3fc) | ((_v & 0xc) >> 2); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static inline int start_tsi(struct da9034_touch *touch) | 
 | { | 
 | 	return da903x_set_bits(touch->da9034_dev, | 
 | 			DA9034_AUTO_CTRL2, DA9034_AUTO_TSI_EN); | 
 | } | 
 |  | 
 | static inline int stop_tsi(struct da9034_touch *touch) | 
 | { | 
 | 	return da903x_clr_bits(touch->da9034_dev, | 
 | 			DA9034_AUTO_CTRL2, DA9034_AUTO_TSI_EN); | 
 | } | 
 |  | 
 | static inline void report_pen_down(struct da9034_touch *touch) | 
 | { | 
 | 	int x = touch->last_x; | 
 | 	int y = touch->last_y; | 
 |  | 
 | 	x &= 0xfff; | 
 | 	if (touch->x_inverted) | 
 | 		x = 1024 - x; | 
 | 	y &= 0xfff; | 
 | 	if (touch->y_inverted) | 
 | 		y = 1024 - y; | 
 |  | 
 | 	input_report_abs(touch->input_dev, ABS_X, x); | 
 | 	input_report_abs(touch->input_dev, ABS_Y, y); | 
 | 	input_report_key(touch->input_dev, BTN_TOUCH, 1); | 
 |  | 
 | 	input_sync(touch->input_dev); | 
 | } | 
 |  | 
 | static inline void report_pen_up(struct da9034_touch *touch) | 
 | { | 
 | 	input_report_key(touch->input_dev, BTN_TOUCH, 0); | 
 | 	input_sync(touch->input_dev); | 
 | } | 
 |  | 
 | static void da9034_event_handler(struct da9034_touch *touch, int event) | 
 | { | 
 | 	int err; | 
 |  | 
 | 	switch (touch->state) { | 
 | 	case STATE_IDLE: | 
 | 		if (event != EVENT_PEN_DOWN) | 
 | 			break; | 
 |  | 
 | 		/* Enable auto measurement of the TSI, this will | 
 | 		 * automatically disable pen down detection | 
 | 		 */ | 
 | 		err = start_tsi(touch); | 
 | 		if (err) | 
 | 			goto err_reset; | 
 |  | 
 | 		touch->state = STATE_BUSY; | 
 | 		break; | 
 |  | 
 | 	case STATE_BUSY: | 
 | 		if (event != EVENT_TSI_READY) | 
 | 			break; | 
 |  | 
 | 		err = read_tsi(touch); | 
 | 		if (err) | 
 | 			goto err_reset; | 
 |  | 
 | 		/* Disable auto measurement of the TSI, so that | 
 | 		 * pen down status will be available | 
 | 		 */ | 
 | 		err = stop_tsi(touch); | 
 | 		if (err) | 
 | 			goto err_reset; | 
 |  | 
 | 		touch->state = STATE_STOP; | 
 |  | 
 | 		/* FIXME: PEN_{UP/DOWN} events are expected to be | 
 | 		 * available by stopping TSI, but this is found not | 
 | 		 * always true, delay and simulate such an event | 
 | 		 * here is more reliable | 
 | 		 */ | 
 | 		mdelay(1); | 
 | 		da9034_event_handler(touch, | 
 | 				     is_pen_down(touch) ? EVENT_PEN_DOWN : | 
 | 							  EVENT_PEN_UP); | 
 | 		break; | 
 |  | 
 | 	case STATE_STOP: | 
 | 		if (event == EVENT_PEN_DOWN) { | 
 | 			report_pen_down(touch); | 
 | 			schedule_delayed_work(&touch->tsi_work, | 
 | 				msecs_to_jiffies(touch->interval_ms)); | 
 | 			touch->state = STATE_WAIT; | 
 | 		} | 
 |  | 
 | 		if (event == EVENT_PEN_UP) { | 
 | 			report_pen_up(touch); | 
 | 			touch->state = STATE_IDLE; | 
 | 		} | 
 | 		break; | 
 |  | 
 | 	case STATE_WAIT: | 
 | 		if (event != EVENT_TIMEDOUT) | 
 | 			break; | 
 |  | 
 | 		if (is_pen_down(touch)) { | 
 | 			start_tsi(touch); | 
 | 			touch->state = STATE_BUSY; | 
 | 		} else { | 
 | 			report_pen_up(touch); | 
 | 			touch->state = STATE_IDLE; | 
 | 		} | 
 | 		break; | 
 | 	} | 
 | 	return; | 
 |  | 
 | err_reset: | 
 | 	touch->state = STATE_IDLE; | 
 | 	stop_tsi(touch); | 
 | 	detect_pen_down(touch, 1); | 
 | } | 
 |  | 
 | static void da9034_tsi_work(struct work_struct *work) | 
 | { | 
 | 	struct da9034_touch *touch = | 
 | 		container_of(work, struct da9034_touch, tsi_work.work); | 
 |  | 
 | 	da9034_event_handler(touch, EVENT_TIMEDOUT); | 
 | } | 
 |  | 
 | static int da9034_touch_notifier(struct notifier_block *nb, | 
 | 				 unsigned long event, void *data) | 
 | { | 
 | 	struct da9034_touch *touch = | 
 | 		container_of(nb, struct da9034_touch, notifier); | 
 |  | 
 | 	if (event & DA9034_EVENT_TSI_READY) | 
 | 		da9034_event_handler(touch, EVENT_TSI_READY); | 
 |  | 
 | 	if ((event & DA9034_EVENT_PEN_DOWN) && touch->state == STATE_IDLE) | 
 | 		da9034_event_handler(touch, EVENT_PEN_DOWN); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int da9034_touch_open(struct input_dev *dev) | 
 | { | 
 | 	struct da9034_touch *touch = input_get_drvdata(dev); | 
 | 	int ret; | 
 |  | 
 | 	ret = da903x_register_notifier(touch->da9034_dev, &touch->notifier, | 
 | 			DA9034_EVENT_PEN_DOWN | DA9034_EVENT_TSI_READY); | 
 | 	if (ret) | 
 | 		return -EBUSY; | 
 |  | 
 | 	/* Enable ADC LDO */ | 
 | 	ret = da903x_set_bits(touch->da9034_dev, | 
 | 			DA9034_MANUAL_CTRL, DA9034_LDO_ADC_EN); | 
 | 	if (ret) | 
 | 		return ret; | 
 |  | 
 | 	/* TSI_DELAY: 3 slots, TSI_SKIP: 3 slots */ | 
 | 	ret = da903x_write(touch->da9034_dev, DA9034_TSI_CTRL1, 0x1b); | 
 | 	if (ret) | 
 | 		return ret; | 
 |  | 
 | 	ret = da903x_write(touch->da9034_dev, DA9034_TSI_CTRL2, 0x00); | 
 | 	if (ret) | 
 | 		return ret; | 
 |  | 
 | 	touch->state = STATE_IDLE; | 
 | 	detect_pen_down(touch, 1); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static void da9034_touch_close(struct input_dev *dev) | 
 | { | 
 | 	struct da9034_touch *touch = input_get_drvdata(dev); | 
 |  | 
 | 	da903x_unregister_notifier(touch->da9034_dev, &touch->notifier, | 
 | 			DA9034_EVENT_PEN_DOWN | DA9034_EVENT_TSI_READY); | 
 |  | 
 | 	cancel_delayed_work_sync(&touch->tsi_work); | 
 |  | 
 | 	touch->state = STATE_IDLE; | 
 | 	stop_tsi(touch); | 
 | 	detect_pen_down(touch, 0); | 
 |  | 
 | 	/* Disable ADC LDO */ | 
 | 	da903x_clr_bits(touch->da9034_dev, | 
 | 			DA9034_MANUAL_CTRL, DA9034_LDO_ADC_EN); | 
 | } | 
 |  | 
 |  | 
 | static int da9034_touch_probe(struct platform_device *pdev) | 
 | { | 
 | 	struct da9034_touch_pdata *pdata = dev_get_platdata(&pdev->dev); | 
 | 	struct da9034_touch *touch; | 
 | 	struct input_dev *input_dev; | 
 | 	int error; | 
 |  | 
 | 	touch = devm_kzalloc(&pdev->dev, sizeof(struct da9034_touch), | 
 | 			     GFP_KERNEL); | 
 | 	if (!touch) { | 
 | 		dev_err(&pdev->dev, "failed to allocate driver data\n"); | 
 | 		return -ENOMEM; | 
 | 	} | 
 |  | 
 | 	touch->da9034_dev = pdev->dev.parent; | 
 |  | 
 | 	if (pdata) { | 
 | 		touch->interval_ms	= pdata->interval_ms; | 
 | 		touch->x_inverted	= pdata->x_inverted; | 
 | 		touch->y_inverted	= pdata->y_inverted; | 
 | 	} else { | 
 | 		/* fallback into default */ | 
 | 		touch->interval_ms	= 10; | 
 | 	} | 
 |  | 
 | 	INIT_DELAYED_WORK(&touch->tsi_work, da9034_tsi_work); | 
 | 	touch->notifier.notifier_call = da9034_touch_notifier; | 
 |  | 
 | 	input_dev = devm_input_allocate_device(&pdev->dev); | 
 | 	if (!input_dev) { | 
 | 		dev_err(&pdev->dev, "failed to allocate input device\n"); | 
 | 		return -ENOMEM; | 
 | 	} | 
 |  | 
 | 	input_dev->name		= pdev->name; | 
 | 	input_dev->open		= da9034_touch_open; | 
 | 	input_dev->close	= da9034_touch_close; | 
 | 	input_dev->dev.parent	= &pdev->dev; | 
 |  | 
 | 	__set_bit(EV_ABS, input_dev->evbit); | 
 | 	__set_bit(ABS_X, input_dev->absbit); | 
 | 	__set_bit(ABS_Y, input_dev->absbit); | 
 | 	input_set_abs_params(input_dev, ABS_X, 0, 1023, 0, 0); | 
 | 	input_set_abs_params(input_dev, ABS_Y, 0, 1023, 0, 0); | 
 |  | 
 | 	__set_bit(EV_KEY, input_dev->evbit); | 
 | 	__set_bit(BTN_TOUCH, input_dev->keybit); | 
 |  | 
 | 	touch->input_dev = input_dev; | 
 | 	input_set_drvdata(input_dev, touch); | 
 |  | 
 | 	error = input_register_device(input_dev); | 
 | 	if (error) | 
 | 		return error; | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static struct platform_driver da9034_touch_driver = { | 
 | 	.driver	= { | 
 | 		.name	= "da9034-touch", | 
 | 	}, | 
 | 	.probe		= da9034_touch_probe, | 
 | }; | 
 | module_platform_driver(da9034_touch_driver); | 
 |  | 
 | MODULE_DESCRIPTION("Touchscreen driver for Dialog Semiconductor DA9034"); | 
 | MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>, Bin Yang <bin.yang@marvell.com>"); | 
 | MODULE_LICENSE("GPL"); | 
 | MODULE_ALIAS("platform:da9034-touch"); |