2 * Samsung S3C24XX touchscreen driver
4 * This program is free software; you can redistribute it and/or modify
5 * it under the term of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 * Copyright 2004 Arnaud Patard <arnaud.patard@rtp-net.org>
19 * Copyright 2008 Ben Dooks <ben-linux@fluff.org>
20 * Copyright 2009 Simtec Electronics <linux@simtec.co.uk>
22 * Additional work by Herbert Pƶtzl <herbert@13thfloor.at> and
23 * Harald Welte <laforge@openmoko.org>
26 #include <linux/errno.h>
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/gpio.h>
30 #include <linux/input.h>
31 #include <linux/init.h>
32 #include <linux/delay.h>
33 #include <linux/interrupt.h>
34 #include <linux/platform_device.h>
35 #include <linux/clk.h>
39 #include <plat/regs-adc.h>
42 #define TSC_SLEEP (S3C2410_ADCTSC_PULL_UP_DISABLE | S3C2410_ADCTSC_XY_PST(0))
45 #define INT_UP (1 << 8)
47 #define WAIT4INT (S3C2410_ADCTSC_YM_SEN | \
48 S3C2410_ADCTSC_YP_SEN | \
49 S3C2410_ADCTSC_XP_SEN | \
50 S3C2410_ADCTSC_XY_PST(3))
52 #define AUTOPST (S3C2410_ADCTSC_YM_SEN | \
53 S3C2410_ADCTSC_YP_SEN | \
54 S3C2410_ADCTSC_XP_SEN | \
55 S3C2410_ADCTSC_AUTO_PST | \
56 S3C2410_ADCTSC_XY_PST(0))
58 #define FEAT_PEN_IRQ (1 << 0) /* HAS ADCCLRINTPNDNUP */
60 /* Per-touchscreen data. */
63 * struct s3c2410ts - driver touchscreen state.
64 * @client: The ADC client we registered with the core driver.
65 * @dev: The device we are bound to.
66 * @input: The input device we registered with the input subsystem.
67 * @clock: The clock for the adc.
68 * @io: Pointer to the IO base.
69 * @xp: The accumulated X position data.
70 * @yp: The accumulated Y position data.
71 * @irq_tc: The interrupt number for pen up/down interrupt
72 * @count: The number of samples collected.
73 * @shift: The log2 of the maximum count to read in one go.
74 * @features: The features supported by the TSADC MOdule.
77 struct s3c_adc_client
*client
;
79 struct input_dev
*input
;
90 static struct s3c2410ts ts
;
93 * get_down - return the down state of the pen
94 * @data0: The data read from ADCDAT0 register.
95 * @data1: The data read from ADCDAT1 register.
97 * Return non-zero if both readings show that the pen is down.
99 static inline bool get_down(unsigned long data0
, unsigned long data1
)
101 /* returns true if both data values show stylus down */
102 return (!(data0
& S3C2410_ADCDAT0_UPDOWN
) &&
103 !(data1
& S3C2410_ADCDAT0_UPDOWN
));
106 static void touch_timer_fire(unsigned long data
)
112 data0
= readl(ts
.io
+ S3C2410_ADCDAT0
);
113 data1
= readl(ts
.io
+ S3C2410_ADCDAT1
);
115 down
= get_down(data0
, data1
);
118 if (ts
.count
== (1 << ts
.shift
)) {
122 dev_dbg(ts
.dev
, "%s: X=%lu, Y=%lu, count=%d\n",
123 __func__
, ts
.xp
, ts
.yp
, ts
.count
);
125 input_report_abs(ts
.input
, ABS_X
, ts
.xp
);
126 input_report_abs(ts
.input
, ABS_Y
, ts
.yp
);
128 input_report_key(ts
.input
, BTN_TOUCH
, 1);
129 input_sync(ts
.input
);
136 s3c_adc_start(ts
.client
, 0, 1 << ts
.shift
);
142 input_report_key(ts
.input
, BTN_TOUCH
, 0);
143 input_sync(ts
.input
);
145 writel(WAIT4INT
| INT_DOWN
, ts
.io
+ S3C2410_ADCTSC
);
149 static DEFINE_TIMER(touch_timer
, touch_timer_fire
, 0, 0);
152 * stylus_irq - touchscreen stylus event interrupt
153 * @irq: The interrupt number
154 * @dev_id: The device ID.
156 * Called when the IRQ_TC is fired for a pen up or down event.
158 static irqreturn_t
stylus_irq(int irq
, void *dev_id
)
164 data0
= readl(ts
.io
+ S3C2410_ADCDAT0
);
165 data1
= readl(ts
.io
+ S3C2410_ADCDAT1
);
167 down
= get_down(data0
, data1
);
169 /* TODO we should never get an interrupt with down set while
170 * the timer is running, but maybe we ought to verify that the
171 * timer isn't running anyways. */
174 s3c_adc_start(ts
.client
, 0, 1 << ts
.shift
);
176 dev_info(ts
.dev
, "%s: count=%d\n", __func__
, ts
.count
);
178 if (ts
.features
& FEAT_PEN_IRQ
) {
179 /* Clear pen down/up interrupt */
180 writel(0x0, ts
.io
+ S3C64XX_ADCCLRINTPNDNUP
);
187 * s3c24xx_ts_conversion - ADC conversion callback
188 * @client: The client that was registered with the ADC core.
189 * @data0: The reading from ADCDAT0.
190 * @data1: The reading from ADCDAT1.
191 * @left: The number of samples left.
193 * Called when a conversion has finished.
195 static void s3c24xx_ts_conversion(struct s3c_adc_client
*client
,
196 unsigned data0
, unsigned data1
,
199 dev_dbg(ts
.dev
, "%s: %d,%d\n", __func__
, data0
, data1
);
206 /* From tests, it seems that it is unlikely to get a pen-up
207 * event during the conversion process which means we can
208 * ignore any pen-up events with less than the requisite
211 * In several thousand conversions, no pen-ups where detected
212 * before count completed.
217 * s3c24xx_ts_select - ADC selection callback.
218 * @client: The client that was registered with the ADC core.
219 * @select: The reason for select.
221 * Called when the ADC core selects (or deslects) us as a client.
223 static void s3c24xx_ts_select(struct s3c_adc_client
*client
, unsigned select
)
226 writel(S3C2410_ADCTSC_PULL_UP_DISABLE
| AUTOPST
,
227 ts
.io
+ S3C2410_ADCTSC
);
229 mod_timer(&touch_timer
, jiffies
+1);
230 writel(WAIT4INT
| INT_UP
, ts
.io
+ S3C2410_ADCTSC
);
235 * s3c2410ts_probe - device core probe entry point
236 * @pdev: The device we are being bound to.
238 * Initialise, find and allocate any resources we need to run and then
239 * register with the ADC and input systems.
241 static int __devinit
s3c2410ts_probe(struct platform_device
*pdev
)
243 struct s3c2410_ts_mach_info
*info
;
244 struct device
*dev
= &pdev
->dev
;
245 struct input_dev
*input_dev
;
246 struct resource
*res
;
249 /* Initialise input stuff */
250 memset(&ts
, 0, sizeof(struct s3c2410ts
));
254 info
= pdev
->dev
.platform_data
;
256 dev_err(dev
, "no platform data, cannot attach\n");
260 dev_dbg(dev
, "initialising touchscreen\n");
262 ts
.clock
= clk_get(dev
, "adc");
263 if (IS_ERR(ts
.clock
)) {
264 dev_err(dev
, "cannot get adc clock source\n");
268 clk_enable(ts
.clock
);
269 dev_dbg(dev
, "got and enabled clocks\n");
271 ts
.irq_tc
= ret
= platform_get_irq(pdev
, 0);
273 dev_err(dev
, "no resource for interrupt\n");
277 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
279 dev_err(dev
, "no resource for registers\n");
284 ts
.io
= ioremap(res
->start
, resource_size(res
));
286 dev_err(dev
, "cannot map registers\n");
291 /* inititalise the gpio */
293 info
->cfg_gpio(to_platform_device(ts
.dev
));
295 ts
.client
= s3c_adc_register(pdev
, s3c24xx_ts_select
,
296 s3c24xx_ts_conversion
, 1);
297 if (IS_ERR(ts
.client
)) {
298 dev_err(dev
, "failed to register adc client\n");
299 ret
= PTR_ERR(ts
.client
);
303 /* Initialise registers */
304 if ((info
->delay
& 0xffff) > 0)
305 writel(info
->delay
& 0xffff, ts
.io
+ S3C2410_ADCDLY
);
307 writel(WAIT4INT
| INT_DOWN
, ts
.io
+ S3C2410_ADCTSC
);
309 input_dev
= input_allocate_device();
311 dev_err(dev
, "Unable to allocate the input device !!\n");
316 ts
.input
= input_dev
;
317 ts
.input
->evbit
[0] = BIT_MASK(EV_KEY
) | BIT_MASK(EV_ABS
);
318 ts
.input
->keybit
[BIT_WORD(BTN_TOUCH
)] = BIT_MASK(BTN_TOUCH
);
319 input_set_abs_params(ts
.input
, ABS_X
, 0, 0x3FF, 0, 0);
320 input_set_abs_params(ts
.input
, ABS_Y
, 0, 0x3FF, 0, 0);
322 ts
.input
->name
= "S3C24XX TouchScreen";
323 ts
.input
->id
.bustype
= BUS_HOST
;
324 ts
.input
->id
.vendor
= 0xDEAD;
325 ts
.input
->id
.product
= 0xBEEF;
326 ts
.input
->id
.version
= 0x0102;
328 ts
.shift
= info
->oversampling_shift
;
329 ts
.features
= platform_get_device_id(pdev
)->driver_data
;
331 ret
= request_irq(ts
.irq_tc
, stylus_irq
, IRQF_DISABLED
,
332 "s3c2410_ts_pen", ts
.input
);
334 dev_err(dev
, "cannot get TC interrupt\n");
338 dev_info(dev
, "driver attached, registering input device\n");
340 /* All went ok, so register to the input system */
341 ret
= input_register_device(ts
.input
);
343 dev_err(dev
, "failed to register input device\n");
351 free_irq(ts
.irq_tc
, ts
.input
);
353 input_unregister_device(ts
.input
);
357 del_timer_sync(&touch_timer
);
363 * s3c2410ts_remove - device core removal entry point
364 * @pdev: The device we are being removed from.
366 * Free up our state ready to be removed.
368 static int __devexit
s3c2410ts_remove(struct platform_device
*pdev
)
370 free_irq(ts
.irq_tc
, ts
.input
);
371 del_timer_sync(&touch_timer
);
373 clk_disable(ts
.clock
);
376 input_unregister_device(ts
.input
);
383 static int s3c2410ts_suspend(struct device
*dev
)
385 writel(TSC_SLEEP
, ts
.io
+ S3C2410_ADCTSC
);
386 disable_irq(ts
.irq_tc
);
387 clk_disable(ts
.clock
);
392 static int s3c2410ts_resume(struct device
*dev
)
394 struct platform_device
*pdev
= to_platform_device(dev
);
395 struct s3c2410_ts_mach_info
*info
= pdev
->dev
.platform_data
;
397 clk_enable(ts
.clock
);
398 enable_irq(ts
.irq_tc
);
400 /* Initialise registers */
401 if ((info
->delay
& 0xffff) > 0)
402 writel(info
->delay
& 0xffff, ts
.io
+ S3C2410_ADCDLY
);
404 writel(WAIT4INT
| INT_DOWN
, ts
.io
+ S3C2410_ADCTSC
);
409 static struct dev_pm_ops s3c_ts_pmops
= {
410 .suspend
= s3c2410ts_suspend
,
411 .resume
= s3c2410ts_resume
,
415 static struct platform_device_id s3cts_driver_ids
[] = {
418 { "s3c64xx-ts", FEAT_PEN_IRQ
},
421 MODULE_DEVICE_TABLE(platform
, s3cts_driver_ids
);
423 static struct platform_driver s3c_ts_driver
= {
425 .name
= "samsung-ts",
426 .owner
= THIS_MODULE
,
431 .id_table
= s3cts_driver_ids
,
432 .probe
= s3c2410ts_probe
,
433 .remove
= __devexit_p(s3c2410ts_remove
),
436 static int __init
s3c2410ts_init(void)
438 return platform_driver_register(&s3c_ts_driver
);
441 static void __exit
s3c2410ts_exit(void)
443 platform_driver_unregister(&s3c_ts_driver
);
446 module_init(s3c2410ts_init
);
447 module_exit(s3c2410ts_exit
);
449 MODULE_AUTHOR("Arnaud Patard <arnaud.patard@rtp-net.org>, "
450 "Ben Dooks <ben@simtec.co.uk>, "
451 "Simtec Electronics <linux@simtec.co.uk>");
452 MODULE_DESCRIPTION("S3C24XX Touchscreen driver");
453 MODULE_LICENSE("GPL v2");