]>
Commit | Line | Data |
---|---|---|
1 | // SPDX-License-Identifier: GPL-2.0-or-later | |
2 | /* | |
3 | * STMicroelectronics STMPE811 Touchscreen Driver | |
4 | * | |
5 | * (C) 2010 Luotao Fu <l.fu@pengutronix.de> | |
6 | * All rights reserved. | |
7 | */ | |
8 | ||
9 | #include <linux/kernel.h> | |
10 | #include <linux/module.h> | |
11 | #include <linux/sched.h> | |
12 | #include <linux/interrupt.h> | |
13 | #include <linux/device.h> | |
14 | #include <linux/of.h> | |
15 | #include <linux/platform_device.h> | |
16 | #include <linux/input.h> | |
17 | #include <linux/slab.h> | |
18 | #include <linux/delay.h> | |
19 | #include <linux/i2c.h> | |
20 | #include <linux/workqueue.h> | |
21 | ||
22 | #include <linux/mfd/stmpe.h> | |
23 | ||
24 | /* Register layouts and functionalities are identical on all stmpexxx variants | |
25 | * with touchscreen controller | |
26 | */ | |
27 | #define STMPE_REG_INT_STA 0x0B | |
28 | #define STMPE_REG_TSC_CTRL 0x40 | |
29 | #define STMPE_REG_TSC_CFG 0x41 | |
30 | #define STMPE_REG_FIFO_TH 0x4A | |
31 | #define STMPE_REG_FIFO_STA 0x4B | |
32 | #define STMPE_REG_FIFO_SIZE 0x4C | |
33 | #define STMPE_REG_TSC_DATA_XYZ 0x52 | |
34 | #define STMPE_REG_TSC_FRACTION_Z 0x56 | |
35 | #define STMPE_REG_TSC_I_DRIVE 0x58 | |
36 | ||
37 | #define OP_MOD_XYZ 0 | |
38 | ||
39 | #define STMPE_TSC_CTRL_TSC_EN (1<<0) | |
40 | ||
41 | #define STMPE_FIFO_STA_RESET (1<<0) | |
42 | ||
43 | #define STMPE_IRQ_TOUCH_DET 0 | |
44 | ||
45 | #define STMPE_TS_NAME "stmpe-ts" | |
46 | #define XY_MASK 0xfff | |
47 | ||
48 | /** | |
49 | * struct stmpe_touch - stmpe811 touch screen controller state | |
50 | * @stmpe: pointer back to STMPE MFD container | |
51 | * @idev: registered input device | |
52 | * @work: a work item used to scan the device | |
53 | * @dev: a pointer back to the MFD cell struct device* | |
54 | * @ave_ctrl: Sample average control | |
55 | * (0 -> 1 sample, 1 -> 2 samples, 2 -> 4 samples, 3 -> 8 samples) | |
56 | * @touch_det_delay: Touch detect interrupt delay | |
57 | * (0 -> 10 us, 1 -> 50 us, 2 -> 100 us, 3 -> 500 us, | |
58 | * 4-> 1 ms, 5 -> 5 ms, 6 -> 10 ms, 7 -> 50 ms) | |
59 | * recommended is 3 | |
60 | * @settling: Panel driver settling time | |
61 | * (0 -> 10 us, 1 -> 100 us, 2 -> 500 us, 3 -> 1 ms, | |
62 | * 4 -> 5 ms, 5 -> 10 ms, 6 for 50 ms, 7 -> 100 ms) | |
63 | * recommended is 2 | |
64 | * @fraction_z: Length of the fractional part in z | |
65 | * (fraction_z ([0..7]) = Count of the fractional part) | |
66 | * recommended is 7 | |
67 | * @i_drive: current limit value of the touchscreen drivers | |
68 | * (0 -> 20 mA typical 35 mA max, 1 -> 50 mA typical 80 mA max) | |
69 | */ | |
70 | struct stmpe_touch { | |
71 | struct stmpe *stmpe; | |
72 | struct input_dev *idev; | |
73 | struct delayed_work work; | |
74 | struct device *dev; | |
75 | u8 ave_ctrl; | |
76 | u8 touch_det_delay; | |
77 | u8 settling; | |
78 | u8 fraction_z; | |
79 | u8 i_drive; | |
80 | }; | |
81 | ||
82 | static int __stmpe_reset_fifo(struct stmpe *stmpe) | |
83 | { | |
84 | int ret; | |
85 | ||
86 | ret = stmpe_set_bits(stmpe, STMPE_REG_FIFO_STA, | |
87 | STMPE_FIFO_STA_RESET, STMPE_FIFO_STA_RESET); | |
88 | if (ret) | |
89 | return ret; | |
90 | ||
91 | return stmpe_set_bits(stmpe, STMPE_REG_FIFO_STA, | |
92 | STMPE_FIFO_STA_RESET, 0); | |
93 | } | |
94 | ||
95 | static void stmpe_work(struct work_struct *work) | |
96 | { | |
97 | int int_sta; | |
98 | u32 timeout = 40; | |
99 | ||
100 | struct stmpe_touch *ts = | |
101 | container_of(work, struct stmpe_touch, work.work); | |
102 | ||
103 | int_sta = stmpe_reg_read(ts->stmpe, STMPE_REG_INT_STA); | |
104 | ||
105 | /* | |
106 | * touch_det sometimes get desasserted or just get stuck. This appears | |
107 | * to be a silicon bug, We still have to clearify this with the | |
108 | * manufacture. As a workaround We release the key anyway if the | |
109 | * touch_det keeps coming in after 4ms, while the FIFO contains no value | |
110 | * during the whole time. | |
111 | */ | |
112 | while ((int_sta & (1 << STMPE_IRQ_TOUCH_DET)) && (timeout > 0)) { | |
113 | timeout--; | |
114 | int_sta = stmpe_reg_read(ts->stmpe, STMPE_REG_INT_STA); | |
115 | udelay(100); | |
116 | } | |
117 | ||
118 | /* reset the FIFO before we report release event */ | |
119 | __stmpe_reset_fifo(ts->stmpe); | |
120 | ||
121 | input_report_abs(ts->idev, ABS_PRESSURE, 0); | |
122 | input_report_key(ts->idev, BTN_TOUCH, 0); | |
123 | input_sync(ts->idev); | |
124 | } | |
125 | ||
126 | static irqreturn_t stmpe_ts_handler(int irq, void *data) | |
127 | { | |
128 | u8 data_set[4]; | |
129 | int x, y, z; | |
130 | struct stmpe_touch *ts = data; | |
131 | ||
132 | /* | |
133 | * Cancel scheduled polling for release if we have new value | |
134 | * available. Wait if the polling is already running. | |
135 | */ | |
136 | cancel_delayed_work_sync(&ts->work); | |
137 | ||
138 | /* | |
139 | * The FIFO sometimes just crashes and stops generating interrupts. This | |
140 | * appears to be a silicon bug. We still have to clearify this with | |
141 | * the manufacture. As a workaround we disable the TSC while we are | |
142 | * collecting data and flush the FIFO after reading | |
143 | */ | |
144 | stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL, | |
145 | STMPE_TSC_CTRL_TSC_EN, 0); | |
146 | ||
147 | stmpe_block_read(ts->stmpe, STMPE_REG_TSC_DATA_XYZ, 4, data_set); | |
148 | ||
149 | x = (data_set[0] << 4) | (data_set[1] >> 4); | |
150 | y = ((data_set[1] & 0xf) << 8) | data_set[2]; | |
151 | z = data_set[3]; | |
152 | ||
153 | input_report_abs(ts->idev, ABS_X, x); | |
154 | input_report_abs(ts->idev, ABS_Y, y); | |
155 | input_report_abs(ts->idev, ABS_PRESSURE, z); | |
156 | input_report_key(ts->idev, BTN_TOUCH, 1); | |
157 | input_sync(ts->idev); | |
158 | ||
159 | /* flush the FIFO after we have read out our values. */ | |
160 | __stmpe_reset_fifo(ts->stmpe); | |
161 | ||
162 | /* reenable the tsc */ | |
163 | stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL, | |
164 | STMPE_TSC_CTRL_TSC_EN, STMPE_TSC_CTRL_TSC_EN); | |
165 | ||
166 | /* start polling for touch_det to detect release */ | |
167 | schedule_delayed_work(&ts->work, msecs_to_jiffies(50)); | |
168 | ||
169 | return IRQ_HANDLED; | |
170 | } | |
171 | ||
172 | static int stmpe_init_hw(struct stmpe_touch *ts) | |
173 | { | |
174 | int ret; | |
175 | u8 tsc_cfg, tsc_cfg_mask; | |
176 | struct stmpe *stmpe = ts->stmpe; | |
177 | struct device *dev = ts->dev; | |
178 | ||
179 | ret = stmpe_enable(stmpe, STMPE_BLOCK_TOUCHSCREEN | STMPE_BLOCK_ADC); | |
180 | if (ret) { | |
181 | dev_err(dev, "Could not enable clock for ADC and TS\n"); | |
182 | return ret; | |
183 | } | |
184 | ||
185 | ret = stmpe811_adc_common_init(stmpe); | |
186 | if (ret) { | |
187 | stmpe_disable(stmpe, STMPE_BLOCK_TOUCHSCREEN | STMPE_BLOCK_ADC); | |
188 | return ret; | |
189 | } | |
190 | ||
191 | tsc_cfg = STMPE_AVE_CTRL(ts->ave_ctrl) | | |
192 | STMPE_DET_DELAY(ts->touch_det_delay) | | |
193 | STMPE_SETTLING(ts->settling); | |
194 | tsc_cfg_mask = STMPE_AVE_CTRL(0xff) | STMPE_DET_DELAY(0xff) | | |
195 | STMPE_SETTLING(0xff); | |
196 | ||
197 | ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_CFG, tsc_cfg_mask, tsc_cfg); | |
198 | if (ret) { | |
199 | dev_err(dev, "Could not config touch\n"); | |
200 | return ret; | |
201 | } | |
202 | ||
203 | ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_FRACTION_Z, | |
204 | STMPE_FRACTION_Z(0xff), STMPE_FRACTION_Z(ts->fraction_z)); | |
205 | if (ret) { | |
206 | dev_err(dev, "Could not config touch\n"); | |
207 | return ret; | |
208 | } | |
209 | ||
210 | ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_I_DRIVE, | |
211 | STMPE_I_DRIVE(0xff), STMPE_I_DRIVE(ts->i_drive)); | |
212 | if (ret) { | |
213 | dev_err(dev, "Could not config touch\n"); | |
214 | return ret; | |
215 | } | |
216 | ||
217 | /* set FIFO to 1 for single point reading */ | |
218 | ret = stmpe_reg_write(stmpe, STMPE_REG_FIFO_TH, 1); | |
219 | if (ret) { | |
220 | dev_err(dev, "Could not set FIFO\n"); | |
221 | return ret; | |
222 | } | |
223 | ||
224 | ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_CTRL, | |
225 | STMPE_OP_MODE(0xff), STMPE_OP_MODE(OP_MOD_XYZ)); | |
226 | if (ret) { | |
227 | dev_err(dev, "Could not set mode\n"); | |
228 | return ret; | |
229 | } | |
230 | ||
231 | return 0; | |
232 | } | |
233 | ||
234 | static int stmpe_ts_open(struct input_dev *dev) | |
235 | { | |
236 | struct stmpe_touch *ts = input_get_drvdata(dev); | |
237 | int ret = 0; | |
238 | ||
239 | ret = __stmpe_reset_fifo(ts->stmpe); | |
240 | if (ret) | |
241 | return ret; | |
242 | ||
243 | return stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL, | |
244 | STMPE_TSC_CTRL_TSC_EN, STMPE_TSC_CTRL_TSC_EN); | |
245 | } | |
246 | ||
247 | static void stmpe_ts_close(struct input_dev *dev) | |
248 | { | |
249 | struct stmpe_touch *ts = input_get_drvdata(dev); | |
250 | ||
251 | cancel_delayed_work_sync(&ts->work); | |
252 | ||
253 | stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL, | |
254 | STMPE_TSC_CTRL_TSC_EN, 0); | |
255 | } | |
256 | ||
257 | static void stmpe_ts_get_platform_info(struct platform_device *pdev, | |
258 | struct stmpe_touch *ts) | |
259 | { | |
260 | struct device_node *np = pdev->dev.of_node; | |
261 | u32 val; | |
262 | ||
263 | if (np) { | |
264 | if (!of_property_read_u32(np, "st,sample-time", &val)) | |
265 | ts->stmpe->sample_time = val; | |
266 | if (!of_property_read_u32(np, "st,mod-12b", &val)) | |
267 | ts->stmpe->mod_12b = val; | |
268 | if (!of_property_read_u32(np, "st,ref-sel", &val)) | |
269 | ts->stmpe->ref_sel = val; | |
270 | if (!of_property_read_u32(np, "st,adc-freq", &val)) | |
271 | ts->stmpe->adc_freq = val; | |
272 | if (!of_property_read_u32(np, "st,ave-ctrl", &val)) | |
273 | ts->ave_ctrl = val; | |
274 | if (!of_property_read_u32(np, "st,touch-det-delay", &val)) | |
275 | ts->touch_det_delay = val; | |
276 | if (!of_property_read_u32(np, "st,settling", &val)) | |
277 | ts->settling = val; | |
278 | if (!of_property_read_u32(np, "st,fraction-z", &val)) | |
279 | ts->fraction_z = val; | |
280 | if (!of_property_read_u32(np, "st,i-drive", &val)) | |
281 | ts->i_drive = val; | |
282 | } | |
283 | } | |
284 | ||
285 | static int stmpe_input_probe(struct platform_device *pdev) | |
286 | { | |
287 | struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent); | |
288 | struct stmpe_touch *ts; | |
289 | struct input_dev *idev; | |
290 | int error; | |
291 | int ts_irq; | |
292 | ||
293 | ts_irq = platform_get_irq_byname(pdev, "FIFO_TH"); | |
294 | if (ts_irq < 0) | |
295 | return ts_irq; | |
296 | ||
297 | ts = devm_kzalloc(&pdev->dev, sizeof(*ts), GFP_KERNEL); | |
298 | if (!ts) | |
299 | return -ENOMEM; | |
300 | ||
301 | idev = devm_input_allocate_device(&pdev->dev); | |
302 | if (!idev) | |
303 | return -ENOMEM; | |
304 | ||
305 | platform_set_drvdata(pdev, ts); | |
306 | ts->stmpe = stmpe; | |
307 | ts->idev = idev; | |
308 | ts->dev = &pdev->dev; | |
309 | ||
310 | stmpe_ts_get_platform_info(pdev, ts); | |
311 | ||
312 | INIT_DELAYED_WORK(&ts->work, stmpe_work); | |
313 | ||
314 | error = devm_request_threaded_irq(&pdev->dev, ts_irq, | |
315 | NULL, stmpe_ts_handler, | |
316 | IRQF_ONESHOT, STMPE_TS_NAME, ts); | |
317 | if (error) { | |
318 | dev_err(&pdev->dev, "Failed to request IRQ %d\n", ts_irq); | |
319 | return error; | |
320 | } | |
321 | ||
322 | error = stmpe_init_hw(ts); | |
323 | if (error) | |
324 | return error; | |
325 | ||
326 | idev->name = STMPE_TS_NAME; | |
327 | idev->phys = STMPE_TS_NAME"/input0"; | |
328 | idev->id.bustype = BUS_I2C; | |
329 | ||
330 | idev->open = stmpe_ts_open; | |
331 | idev->close = stmpe_ts_close; | |
332 | ||
333 | input_set_drvdata(idev, ts); | |
334 | ||
335 | input_set_capability(idev, EV_KEY, BTN_TOUCH); | |
336 | input_set_abs_params(idev, ABS_X, 0, XY_MASK, 0, 0); | |
337 | input_set_abs_params(idev, ABS_Y, 0, XY_MASK, 0, 0); | |
338 | input_set_abs_params(idev, ABS_PRESSURE, 0x0, 0xff, 0, 0); | |
339 | ||
340 | error = input_register_device(idev); | |
341 | if (error) { | |
342 | dev_err(&pdev->dev, "Could not register input device\n"); | |
343 | return error; | |
344 | } | |
345 | ||
346 | return 0; | |
347 | } | |
348 | ||
349 | static int stmpe_ts_remove(struct platform_device *pdev) | |
350 | { | |
351 | struct stmpe_touch *ts = platform_get_drvdata(pdev); | |
352 | ||
353 | stmpe_disable(ts->stmpe, STMPE_BLOCK_TOUCHSCREEN); | |
354 | ||
355 | return 0; | |
356 | } | |
357 | ||
358 | static struct platform_driver stmpe_ts_driver = { | |
359 | .driver = { | |
360 | .name = STMPE_TS_NAME, | |
361 | }, | |
362 | .probe = stmpe_input_probe, | |
363 | .remove = stmpe_ts_remove, | |
364 | }; | |
365 | module_platform_driver(stmpe_ts_driver); | |
366 | ||
367 | static const struct of_device_id stmpe_ts_ids[] = { | |
368 | { .compatible = "st,stmpe-ts", }, | |
369 | { }, | |
370 | }; | |
371 | MODULE_DEVICE_TABLE(of, stmpe_ts_ids); | |
372 | ||
373 | MODULE_AUTHOR("Luotao Fu <l.fu@pengutronix.de>"); | |
374 | MODULE_DESCRIPTION("STMPEXXX touchscreen driver"); | |
375 | MODULE_LICENSE("GPL"); |