1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2015 Broadcom Corporation
4 *
5 */
6 #include <linux/module.h>
7 #include <linux/init.h>
8 #include <linux/input.h>
9 #include <linux/delay.h>
10 #include <linux/interrupt.h>
11 #include <linux/keyboard.h>
12 #include <linux/platform_device.h>
13 #include <linux/slab.h>
14 #include <linux/of.h>
15 #include <asm/irq.h>
16 #include <linux/io.h>
17 #include <linux/clk.h>
18 #include <linux/serio.h>
19 #include <linux/mfd/syscon.h>
20 #include <linux/regmap.h>
21
22 #define IPROC_TS_NAME "iproc-ts"
23
24 #define PEN_DOWN_STATUS 1
25 #define PEN_UP_STATUS 0
26
27 #define X_MIN 0
28 #define Y_MIN 0
29 #define X_MAX 0xFFF
30 #define Y_MAX 0xFFF
31
32 /* Value given by controller for invalid coordinate. */
33 #define INVALID_COORD 0xFFFFFFFF
34
35 /* Register offsets */
36 #define REGCTL1 0x00
37 #define REGCTL2 0x04
38 #define INTERRUPT_THRES 0x08
39 #define INTERRUPT_MASK 0x0c
40
41 #define INTERRUPT_STATUS 0x10
42 #define CONTROLLER_STATUS 0x14
43 #define FIFO_DATA 0x18
44 #define FIFO_DATA_X_Y_MASK 0xFFFF
45 #define ANALOG_CONTROL 0x1c
46
47 #define AUX_DATA 0x20
48 #define DEBOUNCE_CNTR_STAT 0x24
49 #define SCAN_CNTR_STAT 0x28
50 #define REM_CNTR_STAT 0x2c
51
52 #define SETTLING_TIMER_STAT 0x30
53 #define SPARE_REG 0x34
54 #define SOFT_BYPASS_CONTROL 0x38
55 #define SOFT_BYPASS_DATA 0x3c
56
57
58 /* Bit values for INTERRUPT_MASK and INTERRUPT_STATUS regs */
59 #define TS_PEN_INTR_MASK BIT(0)
60 #define TS_FIFO_INTR_MASK BIT(2)
61
62 /* Bit values for CONTROLLER_STATUS reg1 */
63 #define TS_PEN_DOWN BIT(0)
64
65 /* Shift values for control reg1 */
66 #define SCANNING_PERIOD_SHIFT 24
67 #define DEBOUNCE_TIMEOUT_SHIFT 16
68 #define SETTLING_TIMEOUT_SHIFT 8
69 #define TOUCH_TIMEOUT_SHIFT 0
70
71 /* Shift values for coordinates from fifo */
72 #define X_COORD_SHIFT 0
73 #define Y_COORD_SHIFT 16
74
75 /* Bit values for REGCTL2 */
76 #define TS_CONTROLLER_EN_BIT BIT(16)
77 #define TS_CONTROLLER_AVGDATA_SHIFT 8
78 #define TS_CONTROLLER_AVGDATA_MASK (0x7 << TS_CONTROLLER_AVGDATA_SHIFT)
79 #define TS_CONTROLLER_PWR_LDO BIT(5)
80 #define TS_CONTROLLER_PWR_ADC BIT(4)
81 #define TS_CONTROLLER_PWR_BGP BIT(3)
82 #define TS_CONTROLLER_PWR_TS BIT(2)
83 #define TS_WIRE_MODE_BIT BIT(1)
84
85 #define dbg_reg(dev, priv, reg) \
86 do { \
87 u32 val; \
88 regmap_read(priv->regmap, reg, &val); \
89 dev_dbg(dev, "%20s= 0x%08x\n", #reg, val); \
90 } while (0)
91
92 struct tsc_param {
93 /* Each step is 1024 us. Valid 1-256 */
94 u32 scanning_period;
95
96 /* Each step is 512 us. Valid 0-255 */
97 u32 debounce_timeout;
98
99 /*
100 * The settling duration (in ms) is the amount of time the tsc
101 * waits to allow the voltage to settle after turning on the
102 * drivers in detection mode. Valid values: 0-11
103 * 0 = 0.008 ms
104 * 1 = 0.01 ms
105 * 2 = 0.02 ms
106 * 3 = 0.04 ms
107 * 4 = 0.08 ms
108 * 5 = 0.16 ms
109 * 6 = 0.32 ms
110 * 7 = 0.64 ms
111 * 8 = 1.28 ms
112 * 9 = 2.56 ms
113 * 10 = 5.12 ms
114 * 11 = 10.24 ms
115 */
116 u32 settling_timeout;
117
118 /* touch timeout in sample counts */
119 u32 touch_timeout;
120
121 /*
122 * Number of data samples which are averaged before a final data point
123 * is placed into the FIFO
124 */
125 u32 average_data;
126
127 /* FIFO threshold */
128 u32 fifo_threshold;
129
130 /* Optional standard touchscreen properties. */
131 u32 max_x;
132 u32 max_y;
133 u32 fuzz_x;
134 u32 fuzz_y;
135 bool invert_x;
136 bool invert_y;
137 };
138
139 struct iproc_ts_priv {
140 struct platform_device *pdev;
141 struct input_dev *idev;
142
143 struct regmap *regmap;
144 struct clk *tsc_clk;
145
146 int pen_status;
147 struct tsc_param cfg_params;
148 };
149
150 /*
151 * Set default values the same as hardware reset values
152 * except for fifo_threshold with is set to 1.
153 */
154 static const struct tsc_param iproc_default_config = {
155 .scanning_period = 0x5, /* 1 to 256 */
156 .debounce_timeout = 0x28, /* 0 to 255 */
157 .settling_timeout = 0x7, /* 0 to 11 */
158 .touch_timeout = 0xa, /* 0 to 255 */
159 .average_data = 5, /* entry 5 = 32 pts */
160 .fifo_threshold = 1, /* 0 to 31 */
161 .max_x = X_MAX,
162 .max_y = Y_MAX,
163 };
164
ts_reg_dump(struct iproc_ts_priv * priv)165 static void ts_reg_dump(struct iproc_ts_priv *priv)
166 {
167 struct device *dev = &priv->pdev->dev;
168
169 dbg_reg(dev, priv, REGCTL1);
170 dbg_reg(dev, priv, REGCTL2);
171 dbg_reg(dev, priv, INTERRUPT_THRES);
172 dbg_reg(dev, priv, INTERRUPT_MASK);
173 dbg_reg(dev, priv, INTERRUPT_STATUS);
174 dbg_reg(dev, priv, CONTROLLER_STATUS);
175 dbg_reg(dev, priv, FIFO_DATA);
176 dbg_reg(dev, priv, ANALOG_CONTROL);
177 dbg_reg(dev, priv, AUX_DATA);
178 dbg_reg(dev, priv, DEBOUNCE_CNTR_STAT);
179 dbg_reg(dev, priv, SCAN_CNTR_STAT);
180 dbg_reg(dev, priv, REM_CNTR_STAT);
181 dbg_reg(dev, priv, SETTLING_TIMER_STAT);
182 dbg_reg(dev, priv, SPARE_REG);
183 dbg_reg(dev, priv, SOFT_BYPASS_CONTROL);
184 dbg_reg(dev, priv, SOFT_BYPASS_DATA);
185 }
186
iproc_touchscreen_interrupt(int irq,void * data)187 static irqreturn_t iproc_touchscreen_interrupt(int irq, void *data)
188 {
189 struct platform_device *pdev = data;
190 struct iproc_ts_priv *priv = platform_get_drvdata(pdev);
191 u32 intr_status;
192 u32 raw_coordinate;
193 u16 x;
194 u16 y;
195 int i;
196 bool needs_sync = false;
197
198 regmap_read(priv->regmap, INTERRUPT_STATUS, &intr_status);
199 intr_status &= TS_PEN_INTR_MASK | TS_FIFO_INTR_MASK;
200 if (intr_status == 0)
201 return IRQ_NONE;
202
203 /* Clear all interrupt status bits, write-1-clear */
204 regmap_write(priv->regmap, INTERRUPT_STATUS, intr_status);
205 /* Pen up/down */
206 if (intr_status & TS_PEN_INTR_MASK) {
207 regmap_read(priv->regmap, CONTROLLER_STATUS, &priv->pen_status);
208 if (priv->pen_status & TS_PEN_DOWN)
209 priv->pen_status = PEN_DOWN_STATUS;
210 else
211 priv->pen_status = PEN_UP_STATUS;
212
213 input_report_key(priv->idev, BTN_TOUCH, priv->pen_status);
214 needs_sync = true;
215
216 dev_dbg(&priv->pdev->dev,
217 "pen up-down (%d)\n", priv->pen_status);
218 }
219
220 /* coordinates in FIFO exceed the theshold */
221 if (intr_status & TS_FIFO_INTR_MASK) {
222 for (i = 0; i < priv->cfg_params.fifo_threshold; i++) {
223 regmap_read(priv->regmap, FIFO_DATA, &raw_coordinate);
224 if (raw_coordinate == INVALID_COORD)
225 continue;
226
227 /*
228 * The x and y coordinate are 16 bits each
229 * with the x in the lower 16 bits and y in the
230 * upper 16 bits.
231 */
232 x = (raw_coordinate >> X_COORD_SHIFT) &
233 FIFO_DATA_X_Y_MASK;
234 y = (raw_coordinate >> Y_COORD_SHIFT) &
235 FIFO_DATA_X_Y_MASK;
236
237 /* We only want to retain the 12 msb of the 16 */
238 x = (x >> 4) & 0x0FFF;
239 y = (y >> 4) & 0x0FFF;
240
241 /* Adjust x y according to LCD tsc mount angle. */
242 if (priv->cfg_params.invert_x)
243 x = priv->cfg_params.max_x - x;
244
245 if (priv->cfg_params.invert_y)
246 y = priv->cfg_params.max_y - y;
247
248 input_report_abs(priv->idev, ABS_X, x);
249 input_report_abs(priv->idev, ABS_Y, y);
250 needs_sync = true;
251
252 dev_dbg(&priv->pdev->dev, "xy (0x%x 0x%x)\n", x, y);
253 }
254 }
255
256 if (needs_sync)
257 input_sync(priv->idev);
258
259 return IRQ_HANDLED;
260 }
261
iproc_ts_start(struct input_dev * idev)262 static int iproc_ts_start(struct input_dev *idev)
263 {
264 u32 val;
265 u32 mask;
266 int error;
267 struct iproc_ts_priv *priv = input_get_drvdata(idev);
268
269 /* Enable clock */
270 error = clk_prepare_enable(priv->tsc_clk);
271 if (error) {
272 dev_err(&priv->pdev->dev, "%s clk_prepare_enable failed %d\n",
273 __func__, error);
274 return error;
275 }
276
277 /*
278 * Interrupt is generated when:
279 * FIFO reaches the int_th value, and pen event(up/down)
280 */
281 val = TS_PEN_INTR_MASK | TS_FIFO_INTR_MASK;
282 regmap_update_bits(priv->regmap, INTERRUPT_MASK, val, val);
283
284 val = priv->cfg_params.fifo_threshold;
285 regmap_write(priv->regmap, INTERRUPT_THRES, val);
286
287 /* Initialize control reg1 */
288 val = 0;
289 val |= priv->cfg_params.scanning_period << SCANNING_PERIOD_SHIFT;
290 val |= priv->cfg_params.debounce_timeout << DEBOUNCE_TIMEOUT_SHIFT;
291 val |= priv->cfg_params.settling_timeout << SETTLING_TIMEOUT_SHIFT;
292 val |= priv->cfg_params.touch_timeout << TOUCH_TIMEOUT_SHIFT;
293 regmap_write(priv->regmap, REGCTL1, val);
294
295 /* Try to clear all interrupt status */
296 val = TS_FIFO_INTR_MASK | TS_PEN_INTR_MASK;
297 regmap_update_bits(priv->regmap, INTERRUPT_STATUS, val, val);
298
299 /* Initialize control reg2 */
300 val = TS_CONTROLLER_EN_BIT | TS_WIRE_MODE_BIT;
301 val |= priv->cfg_params.average_data << TS_CONTROLLER_AVGDATA_SHIFT;
302
303 mask = (TS_CONTROLLER_AVGDATA_MASK);
304 mask |= (TS_CONTROLLER_PWR_LDO | /* PWR up LDO */
305 TS_CONTROLLER_PWR_ADC | /* PWR up ADC */
306 TS_CONTROLLER_PWR_BGP | /* PWR up BGP */
307 TS_CONTROLLER_PWR_TS); /* PWR up TS */
308 mask |= val;
309 regmap_update_bits(priv->regmap, REGCTL2, mask, val);
310
311 ts_reg_dump(priv);
312
313 return 0;
314 }
315
iproc_ts_stop(struct input_dev * dev)316 static void iproc_ts_stop(struct input_dev *dev)
317 {
318 u32 val;
319 struct iproc_ts_priv *priv = input_get_drvdata(dev);
320
321 /*
322 * Disable FIFO int_th and pen event(up/down)Interrupts only
323 * as the interrupt mask register is shared between ADC, TS and
324 * flextimer.
325 */
326 val = TS_PEN_INTR_MASK | TS_FIFO_INTR_MASK;
327 regmap_update_bits(priv->regmap, INTERRUPT_MASK, val, 0);
328
329 /* Only power down touch screen controller */
330 val = TS_CONTROLLER_PWR_TS;
331 regmap_update_bits(priv->regmap, REGCTL2, val, val);
332
333 clk_disable(priv->tsc_clk);
334 }
335
iproc_get_tsc_config(struct device * dev,struct iproc_ts_priv * priv)336 static int iproc_get_tsc_config(struct device *dev, struct iproc_ts_priv *priv)
337 {
338 struct device_node *np = dev->of_node;
339 u32 val;
340
341 priv->cfg_params = iproc_default_config;
342
343 if (!np)
344 return 0;
345
346 if (of_property_read_u32(np, "scanning_period", &val) >= 0) {
347 if (val < 1 || val > 256) {
348 dev_err(dev, "scanning_period (%u) must be [1-256]\n",
349 val);
350 return -EINVAL;
351 }
352 priv->cfg_params.scanning_period = val;
353 }
354
355 if (of_property_read_u32(np, "debounce_timeout", &val) >= 0) {
356 if (val > 255) {
357 dev_err(dev, "debounce_timeout (%u) must be [0-255]\n",
358 val);
359 return -EINVAL;
360 }
361 priv->cfg_params.debounce_timeout = val;
362 }
363
364 if (of_property_read_u32(np, "settling_timeout", &val) >= 0) {
365 if (val > 11) {
366 dev_err(dev, "settling_timeout (%u) must be [0-11]\n",
367 val);
368 return -EINVAL;
369 }
370 priv->cfg_params.settling_timeout = val;
371 }
372
373 if (of_property_read_u32(np, "touch_timeout", &val) >= 0) {
374 if (val > 255) {
375 dev_err(dev, "touch_timeout (%u) must be [0-255]\n",
376 val);
377 return -EINVAL;
378 }
379 priv->cfg_params.touch_timeout = val;
380 }
381
382 if (of_property_read_u32(np, "average_data", &val) >= 0) {
383 if (val > 8) {
384 dev_err(dev, "average_data (%u) must be [0-8]\n", val);
385 return -EINVAL;
386 }
387 priv->cfg_params.average_data = val;
388 }
389
390 if (of_property_read_u32(np, "fifo_threshold", &val) >= 0) {
391 if (val > 31) {
392 dev_err(dev, "fifo_threshold (%u)) must be [0-31]\n",
393 val);
394 return -EINVAL;
395 }
396 priv->cfg_params.fifo_threshold = val;
397 }
398
399 /* Parse optional properties. */
400 of_property_read_u32(np, "touchscreen-size-x", &priv->cfg_params.max_x);
401 of_property_read_u32(np, "touchscreen-size-y", &priv->cfg_params.max_y);
402
403 of_property_read_u32(np, "touchscreen-fuzz-x",
404 &priv->cfg_params.fuzz_x);
405 of_property_read_u32(np, "touchscreen-fuzz-y",
406 &priv->cfg_params.fuzz_y);
407
408 priv->cfg_params.invert_x =
409 of_property_read_bool(np, "touchscreen-inverted-x");
410 priv->cfg_params.invert_y =
411 of_property_read_bool(np, "touchscreen-inverted-y");
412
413 return 0;
414 }
415
iproc_ts_probe(struct platform_device * pdev)416 static int iproc_ts_probe(struct platform_device *pdev)
417 {
418 struct iproc_ts_priv *priv;
419 struct input_dev *idev;
420 int irq;
421 int error;
422
423 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
424 if (!priv)
425 return -ENOMEM;
426
427 /* touchscreen controller memory mapped regs via syscon*/
428 priv->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
429 "ts_syscon");
430 if (IS_ERR(priv->regmap)) {
431 error = PTR_ERR(priv->regmap);
432 dev_err(&pdev->dev, "unable to map I/O memory:%d\n", error);
433 return error;
434 }
435
436 priv->tsc_clk = devm_clk_get(&pdev->dev, "tsc_clk");
437 if (IS_ERR(priv->tsc_clk)) {
438 error = PTR_ERR(priv->tsc_clk);
439 dev_err(&pdev->dev,
440 "failed getting clock tsc_clk: %d\n", error);
441 return error;
442 }
443
444 priv->pdev = pdev;
445 error = iproc_get_tsc_config(&pdev->dev, priv);
446 if (error) {
447 dev_err(&pdev->dev, "get_tsc_config failed: %d\n", error);
448 return error;
449 }
450
451 idev = devm_input_allocate_device(&pdev->dev);
452 if (!idev) {
453 dev_err(&pdev->dev, "failed to allocate input device\n");
454 return -ENOMEM;
455 }
456
457 priv->idev = idev;
458 priv->pen_status = PEN_UP_STATUS;
459
460 /* Set input device info */
461 idev->name = IPROC_TS_NAME;
462 idev->dev.parent = &pdev->dev;
463
464 idev->id.bustype = BUS_HOST;
465 idev->id.vendor = SERIO_UNKNOWN;
466 idev->id.product = 0;
467 idev->id.version = 0;
468
469 idev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
470 __set_bit(BTN_TOUCH, idev->keybit);
471
472 input_set_abs_params(idev, ABS_X, X_MIN, priv->cfg_params.max_x,
473 priv->cfg_params.fuzz_x, 0);
474 input_set_abs_params(idev, ABS_Y, Y_MIN, priv->cfg_params.max_y,
475 priv->cfg_params.fuzz_y, 0);
476
477 idev->open = iproc_ts_start;
478 idev->close = iproc_ts_stop;
479
480 input_set_drvdata(idev, priv);
481 platform_set_drvdata(pdev, priv);
482
483 /* get interrupt */
484 irq = platform_get_irq(pdev, 0);
485 if (irq < 0)
486 return irq;
487
488 error = devm_request_irq(&pdev->dev, irq,
489 iproc_touchscreen_interrupt,
490 IRQF_SHARED, IPROC_TS_NAME, pdev);
491 if (error)
492 return error;
493
494 error = input_register_device(priv->idev);
495 if (error) {
496 dev_err(&pdev->dev,
497 "failed to register input device: %d\n", error);
498 return error;
499 }
500
501 return 0;
502 }
503
504 static const struct of_device_id iproc_ts_of_match[] = {
505 {.compatible = "brcm,iproc-touchscreen", },
506 { },
507 };
508 MODULE_DEVICE_TABLE(of, iproc_ts_of_match);
509
510 static struct platform_driver iproc_ts_driver = {
511 .probe = iproc_ts_probe,
512 .driver = {
513 .name = IPROC_TS_NAME,
514 .of_match_table = iproc_ts_of_match,
515 },
516 };
517
518 module_platform_driver(iproc_ts_driver);
519
520 MODULE_DESCRIPTION("IPROC Touchscreen driver");
521 MODULE_AUTHOR("Broadcom");
522 MODULE_LICENSE("GPL v2");
523