/drivers/input/touchscreen/corgi_ts.c

  1/*
  2 *  Touchscreen driver for Sharp SL-C7xx and SL-Cxx00 models
  3 *
  4 *  Copyright (c) 2004-2005 Richard Purdie
  5 *
  6 *  This program is free software; you can redistribute it and/or modify
  7 *  it under the terms of the GNU General Public License version 2 as
  8 *  published by the Free Software Foundation.
  9 *
 10 */
 11
 12
 13#include <linux/delay.h>
 14#include <linux/platform_device.h>
 15#include <linux/init.h>
 16#include <linux/input.h>
 17#include <linux/interrupt.h>
 18#include <linux/module.h>
 19#include <linux/slab.h>
 20#include <linux/irq.h>
 21
 22#include <mach/sharpsl.h>
 23#include <mach/hardware.h>
 24#include <mach/pxa2xx-gpio.h>
 25
 26
 27#define PWR_MODE_ACTIVE		0
 28#define PWR_MODE_SUSPEND	1
 29
 30#define X_AXIS_MAX		3830
 31#define X_AXIS_MIN		150
 32#define Y_AXIS_MAX		3830
 33#define Y_AXIS_MIN		190
 34#define PRESSURE_MIN		0
 35#define PRESSURE_MAX		15000
 36
 37struct ts_event {
 38	short pressure;
 39	short x;
 40	short y;
 41};
 42
 43struct corgi_ts {
 44	struct input_dev *input;
 45	struct timer_list timer;
 46	struct ts_event tc;
 47	int pendown;
 48	int power_mode;
 49	int irq_gpio;
 50	struct corgits_machinfo *machinfo;
 51};
 52
 53#ifdef CONFIG_PXA25x
 54#define CCNT(a)		asm volatile ("mrc p14, 0, %0, C1, C0, 0" : "=r"(a))
 55#define PMNC_GET(x)	asm volatile ("mrc p14, 0, %0, C0, C0, 0" : "=r"(x))
 56#define PMNC_SET(x)	asm volatile ("mcr p14, 0, %0, C0, C0, 0" : : "r"(x))
 57#endif
 58#ifdef CONFIG_PXA27x
 59#define CCNT(a)		asm volatile ("mrc p14, 0, %0, C1, C1, 0" : "=r"(a))
 60#define PMNC_GET(x)	asm volatile ("mrc p14, 0, %0, C0, C1, 0" : "=r"(x))
 61#define PMNC_SET(x)	asm volatile ("mcr p14, 0, %0, C0, C1, 0" : : "r"(x))
 62#endif
 63
 64/* ADS7846 Touch Screen Controller bit definitions */
 65#define ADSCTRL_PD0		(1u << 0)	/* PD0 */
 66#define ADSCTRL_PD1		(1u << 1)	/* PD1 */
 67#define ADSCTRL_DFR		(1u << 2)	/* SER/DFR */
 68#define ADSCTRL_MOD		(1u << 3)	/* Mode */
 69#define ADSCTRL_ADR_SH	4	/* Address setting */
 70#define ADSCTRL_STS		(1u << 7)	/* Start Bit */
 71
 72/* External Functions */
 73extern unsigned int get_clk_frequency_khz(int info);
 74
 75static unsigned long calc_waittime(struct corgi_ts *corgi_ts)
 76{
 77	unsigned long hsync_invperiod = corgi_ts->machinfo->get_hsync_invperiod();
 78
 79	if (hsync_invperiod)
 80		return get_clk_frequency_khz(0)*1000/hsync_invperiod;
 81	else
 82		return 0;
 83}
 84
 85static int sync_receive_data_send_cmd(struct corgi_ts *corgi_ts, int doRecive, int doSend,
 86		unsigned int address, unsigned long wait_time)
 87{
 88	unsigned long timer1 = 0, timer2, pmnc = 0;
 89	int pos = 0;
 90
 91	if (wait_time && doSend) {
 92		PMNC_GET(pmnc);
 93		if (!(pmnc & 0x01))
 94			PMNC_SET(0x01);
 95
 96		/* polling HSync */
 97		corgi_ts->machinfo->wait_hsync();
 98		/* get CCNT */
 99		CCNT(timer1);
100	}
101
102	if (doRecive)
103		pos = corgi_ssp_ads7846_get();
104
105	if (doSend) {
106		int cmd = ADSCTRL_PD0 | ADSCTRL_PD1 | (address << ADSCTRL_ADR_SH) | ADSCTRL_STS;
107		/* dummy command */
108		corgi_ssp_ads7846_put(cmd);
109		corgi_ssp_ads7846_get();
110
111		if (wait_time) {
112			/* Wait after HSync */
113			CCNT(timer2);
114			if (timer2-timer1 > wait_time) {
115				/* too slow - timeout, try again */
116				corgi_ts->machinfo->wait_hsync();
117				/* get CCNT */
118				CCNT(timer1);
119				/* Wait after HSync */
120				CCNT(timer2);
121			}
122			while (timer2 - timer1 < wait_time)
123				CCNT(timer2);
124		}
125		corgi_ssp_ads7846_put(cmd);
126		if (wait_time && !(pmnc & 0x01))
127			PMNC_SET(pmnc);
128	}
129	return pos;
130}
131
132static int read_xydata(struct corgi_ts *corgi_ts)
133{
134	unsigned int x, y, z1, z2;
135	unsigned long flags, wait_time;
136
137	/* critical section */
138	local_irq_save(flags);
139	corgi_ssp_ads7846_lock();
140	wait_time = calc_waittime(corgi_ts);
141
142	/* Y-axis */
143	sync_receive_data_send_cmd(corgi_ts, 0, 1, 1u, wait_time);
144
145	/* Y-axis */
146	sync_receive_data_send_cmd(corgi_ts, 1, 1, 1u, wait_time);
147
148	/* X-axis */
149	y = sync_receive_data_send_cmd(corgi_ts, 1, 1, 5u, wait_time);
150
151	/* Z1 */
152	x = sync_receive_data_send_cmd(corgi_ts, 1, 1, 3u, wait_time);
153
154	/* Z2 */
155	z1 = sync_receive_data_send_cmd(corgi_ts, 1, 1, 4u, wait_time);
156	z2 = sync_receive_data_send_cmd(corgi_ts, 1, 0, 4u, wait_time);
157
158	/* Power-Down Enable */
159	corgi_ssp_ads7846_put((1u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
160	corgi_ssp_ads7846_get();
161
162	corgi_ssp_ads7846_unlock();
163	local_irq_restore(flags);
164
165	if (x== 0 || y == 0 || z1 == 0 || (x * (z2 - z1) / z1) >= 15000) {
166		corgi_ts->tc.pressure = 0;
167		return 0;
168	}
169
170	corgi_ts->tc.x = x;
171	corgi_ts->tc.y = y;
172	corgi_ts->tc.pressure = (x * (z2 - z1)) / z1;
173	return 1;
174}
175
176static void new_data(struct corgi_ts *corgi_ts)
177{
178	struct input_dev *dev = corgi_ts->input;
179
180	if (corgi_ts->power_mode != PWR_MODE_ACTIVE)
181		return;
182
183	if (!corgi_ts->tc.pressure && corgi_ts->pendown == 0)
184		return;
185
186	input_report_abs(dev, ABS_X, corgi_ts->tc.x);
187	input_report_abs(dev, ABS_Y, corgi_ts->tc.y);
188	input_report_abs(dev, ABS_PRESSURE, corgi_ts->tc.pressure);
189	input_report_key(dev, BTN_TOUCH, corgi_ts->pendown);
190	input_sync(dev);
191}
192
193static void ts_interrupt_main(struct corgi_ts *corgi_ts, int isTimer)
194{
195	if ((GPLR(IRQ_TO_GPIO(corgi_ts->irq_gpio)) & GPIO_bit(IRQ_TO_GPIO(corgi_ts->irq_gpio))) == 0) {
196		/* Disable Interrupt */
197		set_irq_type(corgi_ts->irq_gpio, IRQ_TYPE_NONE);
198		if (read_xydata(corgi_ts)) {
199			corgi_ts->pendown = 1;
200			new_data(corgi_ts);
201		}
202		mod_timer(&corgi_ts->timer, jiffies + HZ / 100);
203	} else {
204		if (corgi_ts->pendown == 1 || corgi_ts->pendown == 2) {
205			mod_timer(&corgi_ts->timer, jiffies + HZ / 100);
206			corgi_ts->pendown++;
207			return;
208		}
209
210		if (corgi_ts->pendown) {
211			corgi_ts->tc.pressure = 0;
212			new_data(corgi_ts);
213		}
214
215		/* Enable Falling Edge */
216		set_irq_type(corgi_ts->irq_gpio, IRQ_TYPE_EDGE_FALLING);
217		corgi_ts->pendown = 0;
218	}
219}
220
221static void corgi_ts_timer(unsigned long data)
222{
223	struct corgi_ts *corgits_data = (struct corgi_ts *) data;
224
225	ts_interrupt_main(corgits_data, 1);
226}
227
228static irqreturn_t ts_interrupt(int irq, void *dev_id)
229{
230	struct corgi_ts *corgits_data = dev_id;
231
232	ts_interrupt_main(corgits_data, 0);
233	return IRQ_HANDLED;
234}
235
236#ifdef CONFIG_PM
237static int corgits_suspend(struct platform_device *dev, pm_message_t state)
238{
239	struct corgi_ts *corgi_ts = platform_get_drvdata(dev);
240
241	if (corgi_ts->pendown) {
242		del_timer_sync(&corgi_ts->timer);
243		corgi_ts->tc.pressure = 0;
244		new_data(corgi_ts);
245		corgi_ts->pendown = 0;
246	}
247	corgi_ts->power_mode = PWR_MODE_SUSPEND;
248
249	corgi_ssp_ads7846_putget((1u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
250
251	return 0;
252}
253
254static int corgits_resume(struct platform_device *dev)
255{
256	struct corgi_ts *corgi_ts = platform_get_drvdata(dev);
257
258	corgi_ssp_ads7846_putget((4u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
259	/* Enable Falling Edge */
260	set_irq_type(corgi_ts->irq_gpio, IRQ_TYPE_EDGE_FALLING);
261	corgi_ts->power_mode = PWR_MODE_ACTIVE;
262
263	return 0;
264}
265#else
266#define corgits_suspend		NULL
267#define corgits_resume		NULL
268#endif
269
270static int __devinit corgits_probe(struct platform_device *pdev)
271{
272	struct corgi_ts *corgi_ts;
273	struct input_dev *input_dev;
274	int err = -ENOMEM;
275
276	corgi_ts = kzalloc(sizeof(struct corgi_ts), GFP_KERNEL);
277	input_dev = input_allocate_device();
278	if (!corgi_ts || !input_dev)
279		goto fail1;
280
281	platform_set_drvdata(pdev, corgi_ts);
282
283	corgi_ts->machinfo = pdev->dev.platform_data;
284	corgi_ts->irq_gpio = platform_get_irq(pdev, 0);
285
286	if (corgi_ts->irq_gpio < 0) {
287		err = -ENODEV;
288		goto fail1;
289	}
290
291	corgi_ts->input = input_dev;
292
293	init_timer(&corgi_ts->timer);
294	corgi_ts->timer.data = (unsigned long) corgi_ts;
295	corgi_ts->timer.function = corgi_ts_timer;
296
297	input_dev->name = "Corgi Touchscreen";
298	input_dev->phys = "corgits/input0";
299	input_dev->id.bustype = BUS_HOST;
300	input_dev->id.vendor = 0x0001;
301	input_dev->id.product = 0x0002;
302	input_dev->id.version = 0x0100;
303	input_dev->dev.parent = &pdev->dev;
304
305	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
306	input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
307	input_set_abs_params(input_dev, ABS_X, X_AXIS_MIN, X_AXIS_MAX, 0, 0);
308	input_set_abs_params(input_dev, ABS_Y, Y_AXIS_MIN, Y_AXIS_MAX, 0, 0);
309	input_set_abs_params(input_dev, ABS_PRESSURE, PRESSURE_MIN, PRESSURE_MAX, 0, 0);
310
311	pxa_gpio_mode(IRQ_TO_GPIO(corgi_ts->irq_gpio) | GPIO_IN);
312
313	/* Initiaize ADS7846 Difference Reference mode */
314	corgi_ssp_ads7846_putget((1u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
315	mdelay(5);
316	corgi_ssp_ads7846_putget((3u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
317	mdelay(5);
318	corgi_ssp_ads7846_putget((4u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
319	mdelay(5);
320	corgi_ssp_ads7846_putget((5u << ADSCTRL_ADR_SH) | ADSCTRL_STS);
321	mdelay(5);
322
323	if (request_irq(corgi_ts->irq_gpio, ts_interrupt, IRQF_DISABLED, "ts", corgi_ts)) {
324		err = -EBUSY;
325		goto fail1;
326	}
327
328	err = input_register_device(corgi_ts->input);
329	if (err)
330		goto fail2;
331
332	corgi_ts->power_mode = PWR_MODE_ACTIVE;
333
334	/* Enable Falling Edge */
335	set_irq_type(corgi_ts->irq_gpio, IRQ_TYPE_EDGE_FALLING);
336
337	return 0;
338
339 fail2:	free_irq(corgi_ts->irq_gpio, corgi_ts);
340 fail1:	input_free_device(input_dev);
341	kfree(corgi_ts);
342	return err;
343}
344
345static int __devexit corgits_remove(struct platform_device *pdev)
346{
347	struct corgi_ts *corgi_ts = platform_get_drvdata(pdev);
348
349	free_irq(corgi_ts->irq_gpio, corgi_ts);
350	del_timer_sync(&corgi_ts->timer);
351	corgi_ts->machinfo->put_hsync();
352	input_unregister_device(corgi_ts->input);
353	kfree(corgi_ts);
354
355	return 0;
356}
357
358static struct platform_driver corgits_driver = {
359	.probe		= corgits_probe,
360	.remove		= __devexit_p(corgits_remove),
361	.suspend	= corgits_suspend,
362	.resume		= corgits_resume,
363	.driver		= {
364		.name	= "corgi-ts",
365		.owner	= THIS_MODULE,
366	},
367};
368
369static int __init corgits_init(void)
370{
371	return platform_driver_register(&corgits_driver);
372}
373
374static void __exit corgits_exit(void)
375{
376	platform_driver_unregister(&corgits_driver);
377}
378
379module_init(corgits_init);
380module_exit(corgits_exit);
381
382MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
383MODULE_DESCRIPTION("Corgi TouchScreen Driver");
384MODULE_LICENSE("GPL");
385MODULE_ALIAS("platform:corgi-ts");