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/delay.h>
32 #include <linux/interrupt.h>
33 #include <linux/platform_device.h>
34 #include <linux/clk.h>
38 #include <plat/regs-adc.h>
39 #include <linux/platform_data/touchscreen-s3c2410.h>
41 #define TSC_SLEEP (S3C2410_ADCTSC_PULL_UP_DISABLE | S3C2410_ADCTSC_XY_PST(0))
44 #define INT_UP (1 << 8)
46 #define WAIT4INT (S3C2410_ADCTSC_YM_SEN | \
47 S3C2410_ADCTSC_YP_SEN | \
48 S3C2410_ADCTSC_XP_SEN | \
49 S3C2410_ADCTSC_XY_PST(3))
51 #define AUTOPST (S3C2410_ADCTSC_YM_SEN | \
52 S3C2410_ADCTSC_YP_SEN | \
53 S3C2410_ADCTSC_XP_SEN | \
54 S3C2410_ADCTSC_AUTO_PST | \
55 S3C2410_ADCTSC_XY_PST(0))
57 #define FEAT_PEN_IRQ (1 << 0) /* HAS ADCCLRINTPNDNUP */
59 /* Per-touchscreen data. */
62 * struct s3c2410ts - driver touchscreen state.
63 * @client: The ADC client we registered with the core driver.
64 * @dev: The device we are bound to.
65 * @input: The input device we registered with the input subsystem.
66 * @clock: The clock for the adc.
67 * @io: Pointer to the IO base.
68 * @xp: The accumulated X position data.
69 * @yp: The accumulated Y position data.
70 * @irq_tc: The interrupt number for pen up/down interrupt
71 * @count: The number of samples collected.
72 * @shift: The log2 of the maximum count to read in one go.
73 * @features: The features supported by the TSADC MOdule.
76 struct s3c_adc_client
*client
;
78 struct input_dev
*input
;
89 static struct s3c2410ts ts
;
92 * get_down - return the down state of the pen
93 * @data0: The data read from ADCDAT0 register.
94 * @data1: The data read from ADCDAT1 register.
96 * Return non-zero if both readings show that the pen is down.
98 static inline bool get_down(unsigned long data0
, unsigned long data1
)
100 /* returns true if both data values show stylus down */
101 return (!(data0
& S3C2410_ADCDAT0_UPDOWN
) &&
102 !(data1
& S3C2410_ADCDAT0_UPDOWN
));
105 static void touch_timer_fire(struct timer_list
*unused
)
111 data0
= readl(ts
.io
+ S3C2410_ADCDAT0
);
112 data1
= readl(ts
.io
+ S3C2410_ADCDAT1
);
114 down
= get_down(data0
, data1
);
117 if (ts
.count
== (1 << ts
.shift
)) {
121 dev_dbg(ts
.dev
, "%s: X=%lu, Y=%lu, count=%d\n",
122 __func__
, ts
.xp
, ts
.yp
, ts
.count
);
124 input_report_abs(ts
.input
, ABS_X
, ts
.xp
);
125 input_report_abs(ts
.input
, ABS_Y
, ts
.yp
);
127 input_report_key(ts
.input
, BTN_TOUCH
, 1);
128 input_sync(ts
.input
);
135 s3c_adc_start(ts
.client
, 0, 1 << ts
.shift
);
141 input_report_key(ts
.input
, BTN_TOUCH
, 0);
142 input_sync(ts
.input
);
144 writel(WAIT4INT
| INT_DOWN
, ts
.io
+ S3C2410_ADCTSC
);
148 static DEFINE_TIMER(touch_timer
, touch_timer_fire
);
151 * stylus_irq - touchscreen stylus event interrupt
152 * @irq: The interrupt number
153 * @dev_id: The device ID.
155 * Called when the IRQ_TC is fired for a pen up or down event.
157 static irqreturn_t
stylus_irq(int irq
, void *dev_id
)
163 data0
= readl(ts
.io
+ S3C2410_ADCDAT0
);
164 data1
= readl(ts
.io
+ S3C2410_ADCDAT1
);
166 down
= get_down(data0
, data1
);
168 /* TODO we should never get an interrupt with down set while
169 * the timer is running, but maybe we ought to verify that the
170 * timer isn't running anyways. */
173 s3c_adc_start(ts
.client
, 0, 1 << ts
.shift
);
175 dev_dbg(ts
.dev
, "%s: count=%d\n", __func__
, ts
.count
);
177 if (ts
.features
& FEAT_PEN_IRQ
) {
178 /* Clear pen down/up interrupt */
179 writel(0x0, ts
.io
+ S3C64XX_ADCCLRINTPNDNUP
);
186 * s3c24xx_ts_conversion - ADC conversion callback
187 * @client: The client that was registered with the ADC core.
188 * @data0: The reading from ADCDAT0.
189 * @data1: The reading from ADCDAT1.
190 * @left: The number of samples left.
192 * Called when a conversion has finished.
194 static void s3c24xx_ts_conversion(struct s3c_adc_client
*client
,
195 unsigned data0
, unsigned data1
,
198 dev_dbg(ts
.dev
, "%s: %d,%d\n", __func__
, data0
, data1
);
205 /* From tests, it seems that it is unlikely to get a pen-up
206 * event during the conversion process which means we can
207 * ignore any pen-up events with less than the requisite
210 * In several thousand conversions, no pen-ups where detected
211 * before count completed.
216 * s3c24xx_ts_select - ADC selection callback.
217 * @client: The client that was registered with the ADC core.
218 * @select: The reason for select.
220 * Called when the ADC core selects (or deslects) us as a client.
222 static void s3c24xx_ts_select(struct s3c_adc_client
*client
, unsigned select
)
225 writel(S3C2410_ADCTSC_PULL_UP_DISABLE
| AUTOPST
,
226 ts
.io
+ S3C2410_ADCTSC
);
228 mod_timer(&touch_timer
, jiffies
+1);
229 writel(WAIT4INT
| INT_UP
, ts
.io
+ S3C2410_ADCTSC
);
234 * s3c2410ts_probe - device core probe entry point
235 * @pdev: The device we are being bound to.
237 * Initialise, find and allocate any resources we need to run and then
238 * register with the ADC and input systems.
240 static int s3c2410ts_probe(struct platform_device
*pdev
)
242 struct s3c2410_ts_mach_info
*info
;
243 struct device
*dev
= &pdev
->dev
;
244 struct input_dev
*input_dev
;
245 struct resource
*res
;
248 /* Initialise input stuff */
249 memset(&ts
, 0, sizeof(struct s3c2410ts
));
253 info
= dev_get_platdata(dev
);
255 dev_err(dev
, "no platform data, cannot attach\n");
259 dev_dbg(dev
, "initialising touchscreen\n");
261 ts
.clock
= clk_get(dev
, "adc");
262 if (IS_ERR(ts
.clock
)) {
263 dev_err(dev
, "cannot get adc clock source\n");
267 ret
= clk_prepare_enable(ts
.clock
);
269 dev_err(dev
, "Failed! to enabled clocks\n");
272 dev_dbg(dev
, "got and enabled clocks\n");
274 ts
.irq_tc
= ret
= platform_get_irq(pdev
, 0);
276 dev_err(dev
, "no resource for interrupt\n");
280 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
282 dev_err(dev
, "no resource for registers\n");
287 ts
.io
= ioremap(res
->start
, resource_size(res
));
289 dev_err(dev
, "cannot map registers\n");
294 /* inititalise the gpio */
296 info
->cfg_gpio(to_platform_device(ts
.dev
));
298 ts
.client
= s3c_adc_register(pdev
, s3c24xx_ts_select
,
299 s3c24xx_ts_conversion
, 1);
300 if (IS_ERR(ts
.client
)) {
301 dev_err(dev
, "failed to register adc client\n");
302 ret
= PTR_ERR(ts
.client
);
306 /* Initialise registers */
307 if ((info
->delay
& 0xffff) > 0)
308 writel(info
->delay
& 0xffff, ts
.io
+ S3C2410_ADCDLY
);
310 writel(WAIT4INT
| INT_DOWN
, ts
.io
+ S3C2410_ADCTSC
);
312 input_dev
= input_allocate_device();
314 dev_err(dev
, "Unable to allocate the input device !!\n");
319 ts
.input
= input_dev
;
320 ts
.input
->evbit
[0] = BIT_MASK(EV_KEY
) | BIT_MASK(EV_ABS
);
321 ts
.input
->keybit
[BIT_WORD(BTN_TOUCH
)] = BIT_MASK(BTN_TOUCH
);
322 input_set_abs_params(ts
.input
, ABS_X
, 0, 0x3FF, 0, 0);
323 input_set_abs_params(ts
.input
, ABS_Y
, 0, 0x3FF, 0, 0);
325 ts
.input
->name
= "S3C24XX TouchScreen";
326 ts
.input
->id
.bustype
= BUS_HOST
;
327 ts
.input
->id
.vendor
= 0xDEAD;
328 ts
.input
->id
.product
= 0xBEEF;
329 ts
.input
->id
.version
= 0x0102;
331 ts
.shift
= info
->oversampling_shift
;
332 ts
.features
= platform_get_device_id(pdev
)->driver_data
;
334 ret
= request_irq(ts
.irq_tc
, stylus_irq
, 0,
335 "s3c2410_ts_pen", ts
.input
);
337 dev_err(dev
, "cannot get TC interrupt\n");
341 dev_info(dev
, "driver attached, registering input device\n");
343 /* All went ok, so register to the input system */
344 ret
= input_register_device(ts
.input
);
346 dev_err(dev
, "failed to register input device\n");
354 free_irq(ts
.irq_tc
, ts
.input
);
356 input_free_device(ts
.input
);
360 clk_disable_unprepare(ts
.clock
);
361 del_timer_sync(&touch_timer
);
368 * s3c2410ts_remove - device core removal entry point
369 * @pdev: The device we are being removed from.
371 * Free up our state ready to be removed.
373 static int s3c2410ts_remove(struct platform_device
*pdev
)
375 free_irq(ts
.irq_tc
, ts
.input
);
376 del_timer_sync(&touch_timer
);
378 clk_disable_unprepare(ts
.clock
);
381 input_unregister_device(ts
.input
);
388 static int s3c2410ts_suspend(struct device
*dev
)
390 writel(TSC_SLEEP
, ts
.io
+ S3C2410_ADCTSC
);
391 disable_irq(ts
.irq_tc
);
392 clk_disable(ts
.clock
);
397 static int s3c2410ts_resume(struct device
*dev
)
399 struct platform_device
*pdev
= to_platform_device(dev
);
400 struct s3c2410_ts_mach_info
*info
= dev_get_platdata(&pdev
->dev
);
402 clk_enable(ts
.clock
);
403 enable_irq(ts
.irq_tc
);
405 /* Initialise registers */
406 if ((info
->delay
& 0xffff) > 0)
407 writel(info
->delay
& 0xffff, ts
.io
+ S3C2410_ADCDLY
);
409 writel(WAIT4INT
| INT_DOWN
, ts
.io
+ S3C2410_ADCTSC
);
414 static const struct dev_pm_ops s3c_ts_pmops
= {
415 .suspend
= s3c2410ts_suspend
,
416 .resume
= s3c2410ts_resume
,
420 static const struct platform_device_id s3cts_driver_ids
[] = {
423 { "s3c64xx-ts", FEAT_PEN_IRQ
},
426 MODULE_DEVICE_TABLE(platform
, s3cts_driver_ids
);
428 static struct platform_driver s3c_ts_driver
= {
430 .name
= "samsung-ts",
435 .id_table
= s3cts_driver_ids
,
436 .probe
= s3c2410ts_probe
,
437 .remove
= s3c2410ts_remove
,
439 module_platform_driver(s3c_ts_driver
);
441 MODULE_AUTHOR("Arnaud Patard <arnaud.patard@rtp-net.org>, "
442 "Ben Dooks <ben@simtec.co.uk>, "
443 "Simtec Electronics <linux@simtec.co.uk>");
444 MODULE_DESCRIPTION("S3C24XX Touchscreen driver");
445 MODULE_LICENSE("GPL v2");