1/*
2* Copyright (C) 2015 Broadcom Corporation
3*
4* This program is free software; you can redistribute it and/or
5* modify it under the terms of the GNU General Public License as
6* published by the Free Software Foundation version 2.
7*
8* This program is distributed "as is" WITHOUT ANY WARRANTY of any
9* kind, whether express or implied; without even the implied warranty
10* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11* GNU General Public License for more details.
12*/
13#include <linux/module.h>
14#include <linux/init.h>
15#include <linux/input.h>
16#include <linux/delay.h>
17#include <linux/interrupt.h>
18#include <linux/keyboard.h>
19#include <linux/platform_device.h>
20#include <linux/slab.h>
21#include <linux/of.h>
22#include <asm/irq.h>
23#include <linux/io.h>
24#include <linux/clk.h>
25#include <linux/serio.h>
26#include <linux/mfd/syscon.h>
27#include <linux/regmap.h>
28
29#define IPROC_TS_NAME "iproc-ts"
30
31#define PEN_DOWN_STATUS 1
32#define PEN_UP_STATUS 0
33
34#define X_MIN 0
35#define Y_MIN 0
36#define X_MAX 0xFFF
37#define Y_MAX 0xFFF
38
39/* Value given by controller for invalid coordinate. */
40#define INVALID_COORD 0xFFFFFFFF
41
42/* Register offsets */
43#define REGCTL1 0x00
44#define REGCTL2 0x04
45#define INTERRUPT_THRES 0x08
46#define INTERRUPT_MASK 0x0c
47
48#define INTERRUPT_STATUS 0x10
49#define CONTROLLER_STATUS 0x14
50#define FIFO_DATA 0x18
51#define FIFO_DATA_X_Y_MASK 0xFFFF
52#define ANALOG_CONTROL 0x1c
53
54#define AUX_DATA 0x20
55#define DEBOUNCE_CNTR_STAT 0x24
56#define SCAN_CNTR_STAT 0x28
57#define REM_CNTR_STAT 0x2c
58
59#define SETTLING_TIMER_STAT 0x30
60#define SPARE_REG 0x34
61#define SOFT_BYPASS_CONTROL 0x38
62#define SOFT_BYPASS_DATA 0x3c
63
64
65/* Bit values for INTERRUPT_MASK and INTERRUPT_STATUS regs */
66#define TS_PEN_INTR_MASK BIT(0)
67#define TS_FIFO_INTR_MASK BIT(2)
68
69/* Bit values for CONTROLLER_STATUS reg1 */
70#define TS_PEN_DOWN BIT(0)
71
72/* Shift values for control reg1 */
73#define SCANNING_PERIOD_SHIFT 24
74#define DEBOUNCE_TIMEOUT_SHIFT 16
75#define SETTLING_TIMEOUT_SHIFT 8
76#define TOUCH_TIMEOUT_SHIFT 0
77
78/* Shift values for coordinates from fifo */
79#define X_COORD_SHIFT 0
80#define Y_COORD_SHIFT 16
81
82/* Bit values for REGCTL2 */
83#define TS_CONTROLLER_EN_BIT BIT(16)
84#define TS_CONTROLLER_AVGDATA_SHIFT 8
85#define TS_CONTROLLER_AVGDATA_MASK (0x7 << TS_CONTROLLER_AVGDATA_SHIFT)
86#define TS_CONTROLLER_PWR_LDO BIT(5)
87#define TS_CONTROLLER_PWR_ADC BIT(4)
88#define TS_CONTROLLER_PWR_BGP BIT(3)
89#define TS_CONTROLLER_PWR_TS BIT(2)
90#define TS_WIRE_MODE_BIT BIT(1)
91
92#define dbg_reg(dev, priv, reg) \
93do { \
94 u32 val; \
95 regmap_read(priv->regmap, reg, &val); \
96 dev_dbg(dev, "%20s= 0x%08x\n", #reg, val); \
97} while (0)
98
99struct tsc_param {
100 /* Each step is 1024 us. Valid 1-256 */
101 u32 scanning_period;
102
103 /* Each step is 512 us. Valid 0-255 */
104 u32 debounce_timeout;
105
106 /*
107 * The settling duration (in ms) is the amount of time the tsc
108 * waits to allow the voltage to settle after turning on the
109 * drivers in detection mode. Valid values: 0-11
110 * 0 = 0.008 ms
111 * 1 = 0.01 ms
112 * 2 = 0.02 ms
113 * 3 = 0.04 ms
114 * 4 = 0.08 ms
115 * 5 = 0.16 ms
116 * 6 = 0.32 ms
117 * 7 = 0.64 ms
118 * 8 = 1.28 ms
119 * 9 = 2.56 ms
120 * 10 = 5.12 ms
121 * 11 = 10.24 ms
122 */
123 u32 settling_timeout;
124
125 /* touch timeout in sample counts */
126 u32 touch_timeout;
127
128 /*
129 * Number of data samples which are averaged before a final data point
130 * is placed into the FIFO
131 */
132 u32 average_data;
133
134 /* FIFO threshold */
135 u32 fifo_threshold;
136
137 /* Optional standard touchscreen properties. */
138 u32 max_x;
139 u32 max_y;
140 u32 fuzz_x;
141 u32 fuzz_y;
142 bool invert_x;
143 bool invert_y;
144};
145
146struct iproc_ts_priv {
147 struct platform_device *pdev;
148 struct input_dev *idev;
149
150 struct regmap *regmap;
151 struct clk *tsc_clk;
152
153 int pen_status;
154 struct tsc_param cfg_params;
155};
156
157/*
158 * Set default values the same as hardware reset values
159 * except for fifo_threshold with is set to 1.
160 */
161static const struct tsc_param iproc_default_config = {
162 .scanning_period = 0x5, /* 1 to 256 */
163 .debounce_timeout = 0x28, /* 0 to 255 */
164 .settling_timeout = 0x7, /* 0 to 11 */
165 .touch_timeout = 0xa, /* 0 to 255 */
166 .average_data = 5, /* entry 5 = 32 pts */
167 .fifo_threshold = 1, /* 0 to 31 */
168 .max_x = X_MAX,
169 .max_y = Y_MAX,
170};
171
172static void ts_reg_dump(struct iproc_ts_priv *priv)
173{
174 struct device *dev = &priv->pdev->dev;
175
176 dbg_reg(dev, priv, REGCTL1);
177 dbg_reg(dev, priv, REGCTL2);
178 dbg_reg(dev, priv, INTERRUPT_THRES);
179 dbg_reg(dev, priv, INTERRUPT_MASK);
180 dbg_reg(dev, priv, INTERRUPT_STATUS);
181 dbg_reg(dev, priv, CONTROLLER_STATUS);
182 dbg_reg(dev, priv, FIFO_DATA);
183 dbg_reg(dev, priv, ANALOG_CONTROL);
184 dbg_reg(dev, priv, AUX_DATA);
185 dbg_reg(dev, priv, DEBOUNCE_CNTR_STAT);
186 dbg_reg(dev, priv, SCAN_CNTR_STAT);
187 dbg_reg(dev, priv, REM_CNTR_STAT);
188 dbg_reg(dev, priv, SETTLING_TIMER_STAT);
189 dbg_reg(dev, priv, SPARE_REG);
190 dbg_reg(dev, priv, SOFT_BYPASS_CONTROL);
191 dbg_reg(dev, priv, SOFT_BYPASS_DATA);
192}
193
194static irqreturn_t iproc_touchscreen_interrupt(int irq, void *data)
195{
196 struct platform_device *pdev = data;
197 struct iproc_ts_priv *priv = platform_get_drvdata(pdev);
198 u32 intr_status;
199 u32 raw_coordinate;
200 u16 x;
201 u16 y;
202 int i;
203 bool needs_sync = false;
204
205 regmap_read(priv->regmap, INTERRUPT_STATUS, &intr_status);
206 intr_status &= TS_PEN_INTR_MASK | TS_FIFO_INTR_MASK;
207 if (intr_status == 0)
208 return IRQ_NONE;
209
210 /* Clear all interrupt status bits, write-1-clear */
211 regmap_write(priv->regmap, INTERRUPT_STATUS, intr_status);
212 /* Pen up/down */
213 if (intr_status & TS_PEN_INTR_MASK) {
214 regmap_read(priv->regmap, CONTROLLER_STATUS, &priv->pen_status);
215 if (priv->pen_status & TS_PEN_DOWN)
216 priv->pen_status = PEN_DOWN_STATUS;
217 else
218 priv->pen_status = PEN_UP_STATUS;
219
220 input_report_key(priv->idev, BTN_TOUCH, priv->pen_status);
221 needs_sync = true;
222
223 dev_dbg(&priv->pdev->dev,
224 "pen up-down (%d)\n", priv->pen_status);
225 }
226
227 /* coordinates in FIFO exceed the theshold */
228 if (intr_status & TS_FIFO_INTR_MASK) {
229 for (i = 0; i < priv->cfg_params.fifo_threshold; i++) {
230 regmap_read(priv->regmap, FIFO_DATA, &raw_coordinate);
231 if (raw_coordinate == INVALID_COORD)
232 continue;
233
234 /*
235 * The x and y coordinate are 16 bits each
236 * with the x in the lower 16 bits and y in the
237 * upper 16 bits.
238 */
239 x = (raw_coordinate >> X_COORD_SHIFT) &
240 FIFO_DATA_X_Y_MASK;
241 y = (raw_coordinate >> Y_COORD_SHIFT) &
242 FIFO_DATA_X_Y_MASK;
243
244 /* We only want to retain the 12 msb of the 16 */
245 x = (x >> 4) & 0x0FFF;
246 y = (y >> 4) & 0x0FFF;
247
248 /* Adjust x y according to LCD tsc mount angle. */
249 if (priv->cfg_params.invert_x)
250 x = priv->cfg_params.max_x - x;
251
252 if (priv->cfg_params.invert_y)
253 y = priv->cfg_params.max_y - y;
254
255 input_report_abs(priv->idev, ABS_X, x);
256 input_report_abs(priv->idev, ABS_Y, y);
257 needs_sync = true;
258
259 dev_dbg(&priv->pdev->dev, "xy (0x%x 0x%x)\n", x, y);
260 }
261 }
262
263 if (needs_sync)
264 input_sync(priv->idev);
265
266 return IRQ_HANDLED;
267}
268
269static int iproc_ts_start(struct input_dev *idev)
270{
271 u32 val;
272 u32 mask;
273 int error;
274 struct iproc_ts_priv *priv = input_get_drvdata(idev);
275
276 /* Enable clock */
277 error = clk_prepare_enable(priv->tsc_clk);
278 if (error) {
279 dev_err(&priv->pdev->dev, "%s clk_prepare_enable failed %d\n",
280 __func__, error);
281 return error;
282 }
283
284 /*
285 * Interrupt is generated when:
286 * FIFO reaches the int_th value, and pen event(up/down)
287 */
288 val = TS_PEN_INTR_MASK | TS_FIFO_INTR_MASK;
289 regmap_update_bits(priv->regmap, INTERRUPT_MASK, val, val);
290
291 val = priv->cfg_params.fifo_threshold;
292 regmap_write(priv->regmap, INTERRUPT_THRES, val);
293
294 /* Initialize control reg1 */
295 val = 0;
296 val |= priv->cfg_params.scanning_period << SCANNING_PERIOD_SHIFT;
297 val |= priv->cfg_params.debounce_timeout << DEBOUNCE_TIMEOUT_SHIFT;
298 val |= priv->cfg_params.settling_timeout << SETTLING_TIMEOUT_SHIFT;
299 val |= priv->cfg_params.touch_timeout << TOUCH_TIMEOUT_SHIFT;
300 regmap_write(priv->regmap, REGCTL1, val);
301
302 /* Try to clear all interrupt status */
303 val = TS_FIFO_INTR_MASK | TS_PEN_INTR_MASK;
304 regmap_update_bits(priv->regmap, INTERRUPT_STATUS, val, val);
305
306 /* Initialize control reg2 */
307 val = TS_CONTROLLER_EN_BIT | TS_WIRE_MODE_BIT;
308 val |= priv->cfg_params.average_data << TS_CONTROLLER_AVGDATA_SHIFT;
309
310 mask = (TS_CONTROLLER_AVGDATA_MASK);
311 mask |= (TS_CONTROLLER_PWR_LDO | /* PWR up LDO */
312 TS_CONTROLLER_PWR_ADC | /* PWR up ADC */
313 TS_CONTROLLER_PWR_BGP | /* PWR up BGP */
314 TS_CONTROLLER_PWR_TS); /* PWR up TS */
315 mask |= val;
316 regmap_update_bits(priv->regmap, REGCTL2, mask, val);
317
318 ts_reg_dump(priv);
319
320 return 0;
321}
322
323static void iproc_ts_stop(struct input_dev *dev)
324{
325 u32 val;
326 struct iproc_ts_priv *priv = input_get_drvdata(dev);
327
328 /*
329 * Disable FIFO int_th and pen event(up/down)Interrupts only
330 * as the interrupt mask register is shared between ADC, TS and
331 * flextimer.
332 */
333 val = TS_PEN_INTR_MASK | TS_FIFO_INTR_MASK;
334 regmap_update_bits(priv->regmap, INTERRUPT_MASK, val, 0);
335
336 /* Only power down touch screen controller */
337 val = TS_CONTROLLER_PWR_TS;
338 regmap_update_bits(priv->regmap, REGCTL2, val, val);
339
340 clk_disable(priv->tsc_clk);
341}
342
343static int iproc_get_tsc_config(struct device *dev, struct iproc_ts_priv *priv)
344{
345 struct device_node *np = dev->of_node;
346 u32 val;
347
348 priv->cfg_params = iproc_default_config;
349
350 if (!np)
351 return 0;
352
353 if (of_property_read_u32(np, "scanning_period", &val) >= 0) {
354 if (val < 1 || val > 256) {
355 dev_err(dev, "scanning_period (%u) must be [1-256]\n",
356 val);
357 return -EINVAL;
358 }
359 priv->cfg_params.scanning_period = val;
360 }
361
362 if (of_property_read_u32(np, "debounce_timeout", &val) >= 0) {
363 if (val > 255) {
364 dev_err(dev, "debounce_timeout (%u) must be [0-255]\n",
365 val);
366 return -EINVAL;
367 }
368 priv->cfg_params.debounce_timeout = val;
369 }
370
371 if (of_property_read_u32(np, "settling_timeout", &val) >= 0) {
372 if (val > 11) {
373 dev_err(dev, "settling_timeout (%u) must be [0-11]\n",
374 val);
375 return -EINVAL;
376 }
377 priv->cfg_params.settling_timeout = val;
378 }
379
380 if (of_property_read_u32(np, "touch_timeout", &val) >= 0) {
381 if (val > 255) {
382 dev_err(dev, "touch_timeout (%u) must be [0-255]\n",
383 val);
384 return -EINVAL;
385 }
386 priv->cfg_params.touch_timeout = val;
387 }
388
389 if (of_property_read_u32(np, "average_data", &val) >= 0) {
390 if (val > 8) {
391 dev_err(dev, "average_data (%u) must be [0-8]\n", val);
392 return -EINVAL;
393 }
394 priv->cfg_params.average_data = val;
395 }
396
397 if (of_property_read_u32(np, "fifo_threshold", &val) >= 0) {
398 if (val > 31) {
399 dev_err(dev, "fifo_threshold (%u)) must be [0-31]\n",
400 val);
401 return -EINVAL;
402 }
403 priv->cfg_params.fifo_threshold = val;
404 }
405
406 /* Parse optional properties. */
407 of_property_read_u32(np, "touchscreen-size-x", &priv->cfg_params.max_x);
408 of_property_read_u32(np, "touchscreen-size-y", &priv->cfg_params.max_y);
409
410 of_property_read_u32(np, "touchscreen-fuzz-x",
411 &priv->cfg_params.fuzz_x);
412 of_property_read_u32(np, "touchscreen-fuzz-y",
413 &priv->cfg_params.fuzz_y);
414
415 priv->cfg_params.invert_x =
416 of_property_read_bool(np, "touchscreen-inverted-x");
417 priv->cfg_params.invert_y =
418 of_property_read_bool(np, "touchscreen-inverted-y");
419
420 return 0;
421}
422
423static int iproc_ts_probe(struct platform_device *pdev)
424{
425 struct iproc_ts_priv *priv;
426 struct input_dev *idev;
427 int irq;
428 int error;
429
430 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
431 if (!priv)
432 return -ENOMEM;
433
434 /* touchscreen controller memory mapped regs via syscon*/
435 priv->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
436 "ts_syscon");
437 if (IS_ERR(priv->regmap)) {
438 error = PTR_ERR(priv->regmap);
439 dev_err(&pdev->dev, "unable to map I/O memory:%d\n", error);
440 return error;
441 }
442
443 priv->tsc_clk = devm_clk_get(&pdev->dev, "tsc_clk");
444 if (IS_ERR(priv->tsc_clk)) {
445 error = PTR_ERR(priv->tsc_clk);
446 dev_err(&pdev->dev,
447 "failed getting clock tsc_clk: %d\n", error);
448 return error;
449 }
450
451 priv->pdev = pdev;
452 error = iproc_get_tsc_config(&pdev->dev, priv);
453 if (error) {
454 dev_err(&pdev->dev, "get_tsc_config failed: %d\n", error);
455 return error;
456 }
457
458 idev = devm_input_allocate_device(&pdev->dev);
459 if (!idev) {
460 dev_err(&pdev->dev, "failed to allocate input device\n");
461 return -ENOMEM;
462 }
463
464 priv->idev = idev;
465 priv->pen_status = PEN_UP_STATUS;
466
467 /* Set input device info */
468 idev->name = IPROC_TS_NAME;
469 idev->dev.parent = &pdev->dev;
470
471 idev->id.bustype = BUS_HOST;
472 idev->id.vendor = SERIO_UNKNOWN;
473 idev->id.product = 0;
474 idev->id.version = 0;
475
476 idev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
477 __set_bit(BTN_TOUCH, idev->keybit);
478
479 input_set_abs_params(idev, ABS_X, X_MIN, priv->cfg_params.max_x,
480 priv->cfg_params.fuzz_x, 0);
481 input_set_abs_params(idev, ABS_Y, Y_MIN, priv->cfg_params.max_y,
482 priv->cfg_params.fuzz_y, 0);
483
484 idev->open = iproc_ts_start;
485 idev->close = iproc_ts_stop;
486
487 input_set_drvdata(idev, priv);
488 platform_set_drvdata(pdev, priv);
489
490 /* get interrupt */
491 irq = platform_get_irq(pdev, 0);
492 if (irq < 0) {
493 dev_err(&pdev->dev, "platform_get_irq failed: %d\n", irq);
494 return irq;
495 }
496
497 error = devm_request_irq(&pdev->dev, irq,
498 iproc_touchscreen_interrupt,
499 IRQF_SHARED, IPROC_TS_NAME, pdev);
500 if (error)
501 return error;
502
503 error = input_register_device(priv->idev);
504 if (error) {
505 dev_err(&pdev->dev,
506 "failed to register input device: %d\n", error);
507 return error;
508 }
509
510 return 0;
511}
512
513static const struct of_device_id iproc_ts_of_match[] = {
514 {.compatible = "brcm,iproc-touchscreen", },
515 { },
516};
517MODULE_DEVICE_TABLE(of, iproc_ts_of_match);
518
519static struct platform_driver iproc_ts_driver = {
520 .probe = iproc_ts_probe,
521 .driver = {
522 .name = IPROC_TS_NAME,
523 .of_match_table = of_match_ptr(iproc_ts_of_match),
524 },
525};
526
527module_platform_driver(iproc_ts_driver);
528
529MODULE_DESCRIPTION("IPROC Touchscreen driver");
530MODULE_AUTHOR("Broadcom");
531MODULE_LICENSE("GPL v2");
532