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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Input driver for Microchip CAP11xx based capacitive touch sensors
4 *
5 * (c) 2014 Daniel Mack <linux@zonque.org>
6 */
7
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/interrupt.h>
11#include <linux/input.h>
12#include <linux/leds.h>
13#include <linux/of_irq.h>
14#include <linux/regmap.h>
15#include <linux/i2c.h>
16#include <linux/gpio/consumer.h>
17
18#define CAP11XX_REG_MAIN_CONTROL 0x00
19#define CAP11XX_REG_MAIN_CONTROL_GAIN_SHIFT (6)
20#define CAP11XX_REG_MAIN_CONTROL_GAIN_MASK (0xc0)
21#define CAP11XX_REG_MAIN_CONTROL_DLSEEP BIT(4)
22#define CAP11XX_REG_GENERAL_STATUS 0x02
23#define CAP11XX_REG_SENSOR_INPUT 0x03
24#define CAP11XX_REG_NOISE_FLAG_STATUS 0x0a
25#define CAP11XX_REG_SENOR_DELTA(X) (0x10 + (X))
26#define CAP11XX_REG_SENSITIVITY_CONTROL 0x1f
27#define CAP11XX_REG_CONFIG 0x20
28#define CAP11XX_REG_SENSOR_ENABLE 0x21
29#define CAP11XX_REG_SENSOR_CONFIG 0x22
30#define CAP11XX_REG_SENSOR_CONFIG2 0x23
31#define CAP11XX_REG_SAMPLING_CONFIG 0x24
32#define CAP11XX_REG_CALIBRATION 0x26
33#define CAP11XX_REG_INT_ENABLE 0x27
34#define CAP11XX_REG_REPEAT_RATE 0x28
35#define CAP11XX_REG_MT_CONFIG 0x2a
36#define CAP11XX_REG_MT_PATTERN_CONFIG 0x2b
37#define CAP11XX_REG_MT_PATTERN 0x2d
38#define CAP11XX_REG_RECALIB_CONFIG 0x2f
39#define CAP11XX_REG_SENSOR_THRESH(X) (0x30 + (X))
40#define CAP11XX_REG_SENSOR_NOISE_THRESH 0x38
41#define CAP11XX_REG_STANDBY_CHANNEL 0x40
42#define CAP11XX_REG_STANDBY_CONFIG 0x41
43#define CAP11XX_REG_STANDBY_SENSITIVITY 0x42
44#define CAP11XX_REG_STANDBY_THRESH 0x43
45#define CAP11XX_REG_CONFIG2 0x44
46#define CAP11XX_REG_CONFIG2_ALT_POL BIT(6)
47#define CAP11XX_REG_SENSOR_BASE_CNT(X) (0x50 + (X))
48#define CAP11XX_REG_LED_POLARITY 0x73
49#define CAP11XX_REG_LED_OUTPUT_CONTROL 0x74
50
51#define CAP11XX_REG_LED_DUTY_CYCLE_1 0x90
52#define CAP11XX_REG_LED_DUTY_CYCLE_2 0x91
53#define CAP11XX_REG_LED_DUTY_CYCLE_3 0x92
54#define CAP11XX_REG_LED_DUTY_CYCLE_4 0x93
55
56#define CAP11XX_REG_LED_DUTY_MIN_MASK (0x0f)
57#define CAP11XX_REG_LED_DUTY_MIN_MASK_SHIFT (0)
58#define CAP11XX_REG_LED_DUTY_MAX_MASK (0xf0)
59#define CAP11XX_REG_LED_DUTY_MAX_MASK_SHIFT (4)
60#define CAP11XX_REG_LED_DUTY_MAX_VALUE (15)
61
62#define CAP11XX_REG_SENSOR_CALIB (0xb1 + (X))
63#define CAP11XX_REG_SENSOR_CALIB_LSB1 0xb9
64#define CAP11XX_REG_SENSOR_CALIB_LSB2 0xba
65#define CAP11XX_REG_PRODUCT_ID 0xfd
66#define CAP11XX_REG_MANUFACTURER_ID 0xfe
67#define CAP11XX_REG_REVISION 0xff
68
69#define CAP11XX_MANUFACTURER_ID 0x5d
70
71#ifdef CONFIG_LEDS_CLASS
72struct cap11xx_led {
73 struct cap11xx_priv *priv;
74 struct led_classdev cdev;
75 u32 reg;
76};
77#endif
78
79struct cap11xx_priv {
80 struct regmap *regmap;
81 struct input_dev *idev;
82
83 struct cap11xx_led *leds;
84 int num_leds;
85
86 /* config */
87 u32 keycodes[];
88};
89
90struct cap11xx_hw_model {
91 u8 product_id;
92 unsigned int num_channels;
93 unsigned int num_leds;
94 bool no_gain;
95};
96
97enum {
98 CAP1106,
99 CAP1126,
100 CAP1188,
101 CAP1206,
102};
103
104static const struct cap11xx_hw_model cap11xx_devices[] = {
105 [CAP1106] = { .product_id = 0x55, .num_channels = 6, .num_leds = 0, .no_gain = false },
106 [CAP1126] = { .product_id = 0x53, .num_channels = 6, .num_leds = 2, .no_gain = false },
107 [CAP1188] = { .product_id = 0x50, .num_channels = 8, .num_leds = 8, .no_gain = false },
108 [CAP1206] = { .product_id = 0x67, .num_channels = 6, .num_leds = 0, .no_gain = true },
109};
110
111static const struct reg_default cap11xx_reg_defaults[] = {
112 { CAP11XX_REG_MAIN_CONTROL, 0x00 },
113 { CAP11XX_REG_GENERAL_STATUS, 0x00 },
114 { CAP11XX_REG_SENSOR_INPUT, 0x00 },
115 { CAP11XX_REG_NOISE_FLAG_STATUS, 0x00 },
116 { CAP11XX_REG_SENSITIVITY_CONTROL, 0x2f },
117 { CAP11XX_REG_CONFIG, 0x20 },
118 { CAP11XX_REG_SENSOR_ENABLE, 0x3f },
119 { CAP11XX_REG_SENSOR_CONFIG, 0xa4 },
120 { CAP11XX_REG_SENSOR_CONFIG2, 0x07 },
121 { CAP11XX_REG_SAMPLING_CONFIG, 0x39 },
122 { CAP11XX_REG_CALIBRATION, 0x00 },
123 { CAP11XX_REG_INT_ENABLE, 0x3f },
124 { CAP11XX_REG_REPEAT_RATE, 0x3f },
125 { CAP11XX_REG_MT_CONFIG, 0x80 },
126 { CAP11XX_REG_MT_PATTERN_CONFIG, 0x00 },
127 { CAP11XX_REG_MT_PATTERN, 0x3f },
128 { CAP11XX_REG_RECALIB_CONFIG, 0x8a },
129 { CAP11XX_REG_SENSOR_THRESH(0), 0x40 },
130 { CAP11XX_REG_SENSOR_THRESH(1), 0x40 },
131 { CAP11XX_REG_SENSOR_THRESH(2), 0x40 },
132 { CAP11XX_REG_SENSOR_THRESH(3), 0x40 },
133 { CAP11XX_REG_SENSOR_THRESH(4), 0x40 },
134 { CAP11XX_REG_SENSOR_THRESH(5), 0x40 },
135 { CAP11XX_REG_SENSOR_NOISE_THRESH, 0x01 },
136 { CAP11XX_REG_STANDBY_CHANNEL, 0x00 },
137 { CAP11XX_REG_STANDBY_CONFIG, 0x39 },
138 { CAP11XX_REG_STANDBY_SENSITIVITY, 0x02 },
139 { CAP11XX_REG_STANDBY_THRESH, 0x40 },
140 { CAP11XX_REG_CONFIG2, 0x40 },
141 { CAP11XX_REG_LED_POLARITY, 0x00 },
142 { CAP11XX_REG_SENSOR_CALIB_LSB1, 0x00 },
143 { CAP11XX_REG_SENSOR_CALIB_LSB2, 0x00 },
144};
145
146static bool cap11xx_volatile_reg(struct device *dev, unsigned int reg)
147{
148 switch (reg) {
149 case CAP11XX_REG_MAIN_CONTROL:
150 case CAP11XX_REG_SENSOR_INPUT:
151 case CAP11XX_REG_SENOR_DELTA(0):
152 case CAP11XX_REG_SENOR_DELTA(1):
153 case CAP11XX_REG_SENOR_DELTA(2):
154 case CAP11XX_REG_SENOR_DELTA(3):
155 case CAP11XX_REG_SENOR_DELTA(4):
156 case CAP11XX_REG_SENOR_DELTA(5):
157 case CAP11XX_REG_PRODUCT_ID:
158 case CAP11XX_REG_MANUFACTURER_ID:
159 case CAP11XX_REG_REVISION:
160 return true;
161 }
162
163 return false;
164}
165
166static const struct regmap_config cap11xx_regmap_config = {
167 .reg_bits = 8,
168 .val_bits = 8,
169
170 .max_register = CAP11XX_REG_REVISION,
171 .reg_defaults = cap11xx_reg_defaults,
172
173 .num_reg_defaults = ARRAY_SIZE(cap11xx_reg_defaults),
174 .cache_type = REGCACHE_RBTREE,
175 .volatile_reg = cap11xx_volatile_reg,
176};
177
178static irqreturn_t cap11xx_thread_func(int irq_num, void *data)
179{
180 struct cap11xx_priv *priv = data;
181 unsigned int status;
182 int ret, i;
183
184 /*
185 * Deassert interrupt. This needs to be done before reading the status
186 * registers, which will not carry valid values otherwise.
187 */
188 ret = regmap_update_bits(priv->regmap, CAP11XX_REG_MAIN_CONTROL, 1, 0);
189 if (ret < 0)
190 goto out;
191
192 ret = regmap_read(priv->regmap, CAP11XX_REG_SENSOR_INPUT, &status);
193 if (ret < 0)
194 goto out;
195
196 for (i = 0; i < priv->idev->keycodemax; i++)
197 input_report_key(priv->idev, priv->keycodes[i],
198 status & (1 << i));
199
200 input_sync(priv->idev);
201
202out:
203 return IRQ_HANDLED;
204}
205
206static int cap11xx_set_sleep(struct cap11xx_priv *priv, bool sleep)
207{
208 /*
209 * DLSEEP mode will turn off all LEDS, prevent this
210 */
211 if (IS_ENABLED(CONFIG_LEDS_CLASS) && priv->num_leds)
212 return 0;
213
214 return regmap_update_bits(priv->regmap, CAP11XX_REG_MAIN_CONTROL,
215 CAP11XX_REG_MAIN_CONTROL_DLSEEP,
216 sleep ? CAP11XX_REG_MAIN_CONTROL_DLSEEP : 0);
217}
218
219static int cap11xx_input_open(struct input_dev *idev)
220{
221 struct cap11xx_priv *priv = input_get_drvdata(idev);
222
223 return cap11xx_set_sleep(priv, false);
224}
225
226static void cap11xx_input_close(struct input_dev *idev)
227{
228 struct cap11xx_priv *priv = input_get_drvdata(idev);
229
230 cap11xx_set_sleep(priv, true);
231}
232
233#ifdef CONFIG_LEDS_CLASS
234static int cap11xx_led_set(struct led_classdev *cdev,
235 enum led_brightness value)
236{
237 struct cap11xx_led *led = container_of(cdev, struct cap11xx_led, cdev);
238 struct cap11xx_priv *priv = led->priv;
239
240 /*
241 * All LEDs share the same duty cycle as this is a HW
242 * limitation. Brightness levels per LED are either
243 * 0 (OFF) and 1 (ON).
244 */
245 return regmap_update_bits(priv->regmap,
246 CAP11XX_REG_LED_OUTPUT_CONTROL,
247 BIT(led->reg),
248 value ? BIT(led->reg) : 0);
249}
250
251static int cap11xx_init_leds(struct device *dev,
252 struct cap11xx_priv *priv, int num_leds)
253{
254 struct device_node *node = dev->of_node, *child;
255 struct cap11xx_led *led;
256 int cnt = of_get_child_count(node);
257 int error;
258
259 if (!num_leds || !cnt)
260 return 0;
261
262 if (cnt > num_leds)
263 return -EINVAL;
264
265 led = devm_kcalloc(dev, cnt, sizeof(struct cap11xx_led), GFP_KERNEL);
266 if (!led)
267 return -ENOMEM;
268
269 priv->leds = led;
270
271 error = regmap_update_bits(priv->regmap,
272 CAP11XX_REG_LED_OUTPUT_CONTROL, 0xff, 0);
273 if (error)
274 return error;
275
276 error = regmap_update_bits(priv->regmap, CAP11XX_REG_LED_DUTY_CYCLE_4,
277 CAP11XX_REG_LED_DUTY_MAX_MASK,
278 CAP11XX_REG_LED_DUTY_MAX_VALUE <<
279 CAP11XX_REG_LED_DUTY_MAX_MASK_SHIFT);
280 if (error)
281 return error;
282
283 for_each_child_of_node(node, child) {
284 u32 reg;
285
286 led->cdev.name =
287 of_get_property(child, "label", NULL) ? : child->name;
288 led->cdev.default_trigger =
289 of_get_property(child, "linux,default-trigger", NULL);
290 led->cdev.flags = 0;
291 led->cdev.brightness_set_blocking = cap11xx_led_set;
292 led->cdev.max_brightness = 1;
293 led->cdev.brightness = LED_OFF;
294
295 error = of_property_read_u32(child, "reg", ®);
296 if (error != 0 || reg >= num_leds) {
297 of_node_put(child);
298 return -EINVAL;
299 }
300
301 led->reg = reg;
302 led->priv = priv;
303
304 error = devm_led_classdev_register(dev, &led->cdev);
305 if (error) {
306 of_node_put(child);
307 return error;
308 }
309
310 priv->num_leds++;
311 led++;
312 }
313
314 return 0;
315}
316#else
317static int cap11xx_init_leds(struct device *dev,
318 struct cap11xx_priv *priv, int num_leds)
319{
320 return 0;
321}
322#endif
323
324static int cap11xx_i2c_probe(struct i2c_client *i2c_client)
325{
326 const struct i2c_device_id *id = i2c_client_get_device_id(i2c_client);
327 struct device *dev = &i2c_client->dev;
328 struct cap11xx_priv *priv;
329 struct device_node *node;
330 const struct cap11xx_hw_model *cap;
331 int i, error, irq, gain = 0;
332 unsigned int val, rev;
333 u32 gain32;
334
335 if (id->driver_data >= ARRAY_SIZE(cap11xx_devices)) {
336 dev_err(dev, "Invalid device ID %lu\n", id->driver_data);
337 return -EINVAL;
338 }
339
340 cap = &cap11xx_devices[id->driver_data];
341 if (!cap || !cap->num_channels) {
342 dev_err(dev, "Invalid device configuration\n");
343 return -EINVAL;
344 }
345
346 priv = devm_kzalloc(dev,
347 struct_size(priv, keycodes, cap->num_channels),
348 GFP_KERNEL);
349 if (!priv)
350 return -ENOMEM;
351
352 priv->regmap = devm_regmap_init_i2c(i2c_client, &cap11xx_regmap_config);
353 if (IS_ERR(priv->regmap))
354 return PTR_ERR(priv->regmap);
355
356 error = regmap_read(priv->regmap, CAP11XX_REG_PRODUCT_ID, &val);
357 if (error)
358 return error;
359
360 if (val != cap->product_id) {
361 dev_err(dev, "Product ID: Got 0x%02x, expected 0x%02x\n",
362 val, cap->product_id);
363 return -ENXIO;
364 }
365
366 error = regmap_read(priv->regmap, CAP11XX_REG_MANUFACTURER_ID, &val);
367 if (error)
368 return error;
369
370 if (val != CAP11XX_MANUFACTURER_ID) {
371 dev_err(dev, "Manufacturer ID: Got 0x%02x, expected 0x%02x\n",
372 val, CAP11XX_MANUFACTURER_ID);
373 return -ENXIO;
374 }
375
376 error = regmap_read(priv->regmap, CAP11XX_REG_REVISION, &rev);
377 if (error < 0)
378 return error;
379
380 dev_info(dev, "CAP11XX detected, revision 0x%02x\n", rev);
381 node = dev->of_node;
382
383 if (!of_property_read_u32(node, "microchip,sensor-gain", &gain32)) {
384 if (cap->no_gain)
385 dev_warn(dev,
386 "This version doesn't support sensor gain\n");
387 else if (is_power_of_2(gain32) && gain32 <= 8)
388 gain = ilog2(gain32);
389 else
390 dev_err(dev, "Invalid sensor-gain value %d\n", gain32);
391 }
392
393 if (id->driver_data != CAP1206) {
394 if (of_property_read_bool(node, "microchip,irq-active-high")) {
395 error = regmap_update_bits(priv->regmap,
396 CAP11XX_REG_CONFIG2,
397 CAP11XX_REG_CONFIG2_ALT_POL,
398 0);
399 if (error)
400 return error;
401 }
402 }
403
404 /* Provide some useful defaults */
405 for (i = 0; i < cap->num_channels; i++)
406 priv->keycodes[i] = KEY_A + i;
407
408 of_property_read_u32_array(node, "linux,keycodes",
409 priv->keycodes, cap->num_channels);
410
411 if (!cap->no_gain) {
412 error = regmap_update_bits(priv->regmap,
413 CAP11XX_REG_MAIN_CONTROL,
414 CAP11XX_REG_MAIN_CONTROL_GAIN_MASK,
415 gain << CAP11XX_REG_MAIN_CONTROL_GAIN_SHIFT);
416 if (error)
417 return error;
418 }
419
420 /* Disable autorepeat. The Linux input system has its own handling. */
421 error = regmap_write(priv->regmap, CAP11XX_REG_REPEAT_RATE, 0);
422 if (error)
423 return error;
424
425 priv->idev = devm_input_allocate_device(dev);
426 if (!priv->idev)
427 return -ENOMEM;
428
429 priv->idev->name = "CAP11XX capacitive touch sensor";
430 priv->idev->id.bustype = BUS_I2C;
431 priv->idev->evbit[0] = BIT_MASK(EV_KEY);
432
433 if (of_property_read_bool(node, "autorepeat"))
434 __set_bit(EV_REP, priv->idev->evbit);
435
436 for (i = 0; i < cap->num_channels; i++)
437 __set_bit(priv->keycodes[i], priv->idev->keybit);
438
439 __clear_bit(KEY_RESERVED, priv->idev->keybit);
440
441 priv->idev->keycode = priv->keycodes;
442 priv->idev->keycodesize = sizeof(priv->keycodes[0]);
443 priv->idev->keycodemax = cap->num_channels;
444
445 priv->idev->id.vendor = CAP11XX_MANUFACTURER_ID;
446 priv->idev->id.product = cap->product_id;
447 priv->idev->id.version = rev;
448
449 priv->idev->open = cap11xx_input_open;
450 priv->idev->close = cap11xx_input_close;
451
452 error = cap11xx_init_leds(dev, priv, cap->num_leds);
453 if (error)
454 return error;
455
456 input_set_drvdata(priv->idev, priv);
457
458 /*
459 * Put the device in deep sleep mode for now.
460 * ->open() will bring it back once the it is actually needed.
461 */
462 cap11xx_set_sleep(priv, true);
463
464 error = input_register_device(priv->idev);
465 if (error)
466 return error;
467
468 irq = irq_of_parse_and_map(node, 0);
469 if (!irq) {
470 dev_err(dev, "Unable to parse or map IRQ\n");
471 return -ENXIO;
472 }
473
474 error = devm_request_threaded_irq(dev, irq, NULL, cap11xx_thread_func,
475 IRQF_ONESHOT, dev_name(dev), priv);
476 if (error)
477 return error;
478
479 return 0;
480}
481
482static const struct of_device_id cap11xx_dt_ids[] = {
483 { .compatible = "microchip,cap1106", },
484 { .compatible = "microchip,cap1126", },
485 { .compatible = "microchip,cap1188", },
486 { .compatible = "microchip,cap1206", },
487 {}
488};
489MODULE_DEVICE_TABLE(of, cap11xx_dt_ids);
490
491static const struct i2c_device_id cap11xx_i2c_ids[] = {
492 { "cap1106", CAP1106 },
493 { "cap1126", CAP1126 },
494 { "cap1188", CAP1188 },
495 { "cap1206", CAP1206 },
496 {}
497};
498MODULE_DEVICE_TABLE(i2c, cap11xx_i2c_ids);
499
500static struct i2c_driver cap11xx_i2c_driver = {
501 .driver = {
502 .name = "cap11xx",
503 .of_match_table = cap11xx_dt_ids,
504 },
505 .id_table = cap11xx_i2c_ids,
506 .probe_new = cap11xx_i2c_probe,
507};
508
509module_i2c_driver(cap11xx_i2c_driver);
510
511MODULE_DESCRIPTION("Microchip CAP11XX driver");
512MODULE_AUTHOR("Daniel Mack <linux@zonque.org>");
513MODULE_LICENSE("GPL v2");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Input driver for Microchip CAP11xx based capacitive touch sensors
4 *
5 * (c) 2014 Daniel Mack <linux@zonque.org>
6 */
7
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/interrupt.h>
11#include <linux/input.h>
12#include <linux/leds.h>
13#include <linux/of_irq.h>
14#include <linux/regmap.h>
15#include <linux/i2c.h>
16#include <linux/gpio/consumer.h>
17
18#define CAP11XX_REG_MAIN_CONTROL 0x00
19#define CAP11XX_REG_MAIN_CONTROL_GAIN_SHIFT (6)
20#define CAP11XX_REG_MAIN_CONTROL_GAIN_MASK (0xc0)
21#define CAP11XX_REG_MAIN_CONTROL_DLSEEP BIT(4)
22#define CAP11XX_REG_GENERAL_STATUS 0x02
23#define CAP11XX_REG_SENSOR_INPUT 0x03
24#define CAP11XX_REG_NOISE_FLAG_STATUS 0x0a
25#define CAP11XX_REG_SENOR_DELTA(X) (0x10 + (X))
26#define CAP11XX_REG_SENSITIVITY_CONTROL 0x1f
27#define CAP11XX_REG_CONFIG 0x20
28#define CAP11XX_REG_SENSOR_ENABLE 0x21
29#define CAP11XX_REG_SENSOR_CONFIG 0x22
30#define CAP11XX_REG_SENSOR_CONFIG2 0x23
31#define CAP11XX_REG_SAMPLING_CONFIG 0x24
32#define CAP11XX_REG_CALIBRATION 0x26
33#define CAP11XX_REG_INT_ENABLE 0x27
34#define CAP11XX_REG_REPEAT_RATE 0x28
35#define CAP11XX_REG_MT_CONFIG 0x2a
36#define CAP11XX_REG_MT_PATTERN_CONFIG 0x2b
37#define CAP11XX_REG_MT_PATTERN 0x2d
38#define CAP11XX_REG_RECALIB_CONFIG 0x2f
39#define CAP11XX_REG_SENSOR_THRESH(X) (0x30 + (X))
40#define CAP11XX_REG_SENSOR_NOISE_THRESH 0x38
41#define CAP11XX_REG_STANDBY_CHANNEL 0x40
42#define CAP11XX_REG_STANDBY_CONFIG 0x41
43#define CAP11XX_REG_STANDBY_SENSITIVITY 0x42
44#define CAP11XX_REG_STANDBY_THRESH 0x43
45#define CAP11XX_REG_CONFIG2 0x44
46#define CAP11XX_REG_CONFIG2_ALT_POL BIT(6)
47#define CAP11XX_REG_SENSOR_BASE_CNT(X) (0x50 + (X))
48#define CAP11XX_REG_LED_POLARITY 0x73
49#define CAP11XX_REG_LED_OUTPUT_CONTROL 0x74
50
51#define CAP11XX_REG_LED_DUTY_CYCLE_1 0x90
52#define CAP11XX_REG_LED_DUTY_CYCLE_2 0x91
53#define CAP11XX_REG_LED_DUTY_CYCLE_3 0x92
54#define CAP11XX_REG_LED_DUTY_CYCLE_4 0x93
55
56#define CAP11XX_REG_LED_DUTY_MIN_MASK (0x0f)
57#define CAP11XX_REG_LED_DUTY_MIN_MASK_SHIFT (0)
58#define CAP11XX_REG_LED_DUTY_MAX_MASK (0xf0)
59#define CAP11XX_REG_LED_DUTY_MAX_MASK_SHIFT (4)
60#define CAP11XX_REG_LED_DUTY_MAX_VALUE (15)
61
62#define CAP11XX_REG_SENSOR_CALIB (0xb1 + (X))
63#define CAP11XX_REG_SENSOR_CALIB_LSB1 0xb9
64#define CAP11XX_REG_SENSOR_CALIB_LSB2 0xba
65#define CAP11XX_REG_PRODUCT_ID 0xfd
66#define CAP11XX_REG_MANUFACTURER_ID 0xfe
67#define CAP11XX_REG_REVISION 0xff
68
69#define CAP11XX_MANUFACTURER_ID 0x5d
70
71#ifdef CONFIG_LEDS_CLASS
72struct cap11xx_led {
73 struct cap11xx_priv *priv;
74 struct led_classdev cdev;
75 u32 reg;
76};
77#endif
78
79struct cap11xx_priv {
80 struct regmap *regmap;
81 struct input_dev *idev;
82
83 struct cap11xx_led *leds;
84 int num_leds;
85
86 /* config */
87 u32 keycodes[];
88};
89
90struct cap11xx_hw_model {
91 u8 product_id;
92 unsigned int num_channels;
93 unsigned int num_leds;
94};
95
96enum {
97 CAP1106,
98 CAP1126,
99 CAP1188,
100};
101
102static const struct cap11xx_hw_model cap11xx_devices[] = {
103 [CAP1106] = { .product_id = 0x55, .num_channels = 6, .num_leds = 0 },
104 [CAP1126] = { .product_id = 0x53, .num_channels = 6, .num_leds = 2 },
105 [CAP1188] = { .product_id = 0x50, .num_channels = 8, .num_leds = 8 },
106};
107
108static const struct reg_default cap11xx_reg_defaults[] = {
109 { CAP11XX_REG_MAIN_CONTROL, 0x00 },
110 { CAP11XX_REG_GENERAL_STATUS, 0x00 },
111 { CAP11XX_REG_SENSOR_INPUT, 0x00 },
112 { CAP11XX_REG_NOISE_FLAG_STATUS, 0x00 },
113 { CAP11XX_REG_SENSITIVITY_CONTROL, 0x2f },
114 { CAP11XX_REG_CONFIG, 0x20 },
115 { CAP11XX_REG_SENSOR_ENABLE, 0x3f },
116 { CAP11XX_REG_SENSOR_CONFIG, 0xa4 },
117 { CAP11XX_REG_SENSOR_CONFIG2, 0x07 },
118 { CAP11XX_REG_SAMPLING_CONFIG, 0x39 },
119 { CAP11XX_REG_CALIBRATION, 0x00 },
120 { CAP11XX_REG_INT_ENABLE, 0x3f },
121 { CAP11XX_REG_REPEAT_RATE, 0x3f },
122 { CAP11XX_REG_MT_CONFIG, 0x80 },
123 { CAP11XX_REG_MT_PATTERN_CONFIG, 0x00 },
124 { CAP11XX_REG_MT_PATTERN, 0x3f },
125 { CAP11XX_REG_RECALIB_CONFIG, 0x8a },
126 { CAP11XX_REG_SENSOR_THRESH(0), 0x40 },
127 { CAP11XX_REG_SENSOR_THRESH(1), 0x40 },
128 { CAP11XX_REG_SENSOR_THRESH(2), 0x40 },
129 { CAP11XX_REG_SENSOR_THRESH(3), 0x40 },
130 { CAP11XX_REG_SENSOR_THRESH(4), 0x40 },
131 { CAP11XX_REG_SENSOR_THRESH(5), 0x40 },
132 { CAP11XX_REG_SENSOR_NOISE_THRESH, 0x01 },
133 { CAP11XX_REG_STANDBY_CHANNEL, 0x00 },
134 { CAP11XX_REG_STANDBY_CONFIG, 0x39 },
135 { CAP11XX_REG_STANDBY_SENSITIVITY, 0x02 },
136 { CAP11XX_REG_STANDBY_THRESH, 0x40 },
137 { CAP11XX_REG_CONFIG2, 0x40 },
138 { CAP11XX_REG_LED_POLARITY, 0x00 },
139 { CAP11XX_REG_SENSOR_CALIB_LSB1, 0x00 },
140 { CAP11XX_REG_SENSOR_CALIB_LSB2, 0x00 },
141};
142
143static bool cap11xx_volatile_reg(struct device *dev, unsigned int reg)
144{
145 switch (reg) {
146 case CAP11XX_REG_MAIN_CONTROL:
147 case CAP11XX_REG_SENSOR_INPUT:
148 case CAP11XX_REG_SENOR_DELTA(0):
149 case CAP11XX_REG_SENOR_DELTA(1):
150 case CAP11XX_REG_SENOR_DELTA(2):
151 case CAP11XX_REG_SENOR_DELTA(3):
152 case CAP11XX_REG_SENOR_DELTA(4):
153 case CAP11XX_REG_SENOR_DELTA(5):
154 case CAP11XX_REG_PRODUCT_ID:
155 case CAP11XX_REG_MANUFACTURER_ID:
156 case CAP11XX_REG_REVISION:
157 return true;
158 }
159
160 return false;
161}
162
163static const struct regmap_config cap11xx_regmap_config = {
164 .reg_bits = 8,
165 .val_bits = 8,
166
167 .max_register = CAP11XX_REG_REVISION,
168 .reg_defaults = cap11xx_reg_defaults,
169
170 .num_reg_defaults = ARRAY_SIZE(cap11xx_reg_defaults),
171 .cache_type = REGCACHE_RBTREE,
172 .volatile_reg = cap11xx_volatile_reg,
173};
174
175static irqreturn_t cap11xx_thread_func(int irq_num, void *data)
176{
177 struct cap11xx_priv *priv = data;
178 unsigned int status;
179 int ret, i;
180
181 /*
182 * Deassert interrupt. This needs to be done before reading the status
183 * registers, which will not carry valid values otherwise.
184 */
185 ret = regmap_update_bits(priv->regmap, CAP11XX_REG_MAIN_CONTROL, 1, 0);
186 if (ret < 0)
187 goto out;
188
189 ret = regmap_read(priv->regmap, CAP11XX_REG_SENSOR_INPUT, &status);
190 if (ret < 0)
191 goto out;
192
193 for (i = 0; i < priv->idev->keycodemax; i++)
194 input_report_key(priv->idev, priv->keycodes[i],
195 status & (1 << i));
196
197 input_sync(priv->idev);
198
199out:
200 return IRQ_HANDLED;
201}
202
203static int cap11xx_set_sleep(struct cap11xx_priv *priv, bool sleep)
204{
205 /*
206 * DLSEEP mode will turn off all LEDS, prevent this
207 */
208 if (IS_ENABLED(CONFIG_LEDS_CLASS) && priv->num_leds)
209 return 0;
210
211 return regmap_update_bits(priv->regmap, CAP11XX_REG_MAIN_CONTROL,
212 CAP11XX_REG_MAIN_CONTROL_DLSEEP,
213 sleep ? CAP11XX_REG_MAIN_CONTROL_DLSEEP : 0);
214}
215
216static int cap11xx_input_open(struct input_dev *idev)
217{
218 struct cap11xx_priv *priv = input_get_drvdata(idev);
219
220 return cap11xx_set_sleep(priv, false);
221}
222
223static void cap11xx_input_close(struct input_dev *idev)
224{
225 struct cap11xx_priv *priv = input_get_drvdata(idev);
226
227 cap11xx_set_sleep(priv, true);
228}
229
230#ifdef CONFIG_LEDS_CLASS
231static int cap11xx_led_set(struct led_classdev *cdev,
232 enum led_brightness value)
233{
234 struct cap11xx_led *led = container_of(cdev, struct cap11xx_led, cdev);
235 struct cap11xx_priv *priv = led->priv;
236
237 /*
238 * All LEDs share the same duty cycle as this is a HW
239 * limitation. Brightness levels per LED are either
240 * 0 (OFF) and 1 (ON).
241 */
242 return regmap_update_bits(priv->regmap,
243 CAP11XX_REG_LED_OUTPUT_CONTROL,
244 BIT(led->reg),
245 value ? BIT(led->reg) : 0);
246}
247
248static int cap11xx_init_leds(struct device *dev,
249 struct cap11xx_priv *priv, int num_leds)
250{
251 struct device_node *node = dev->of_node, *child;
252 struct cap11xx_led *led;
253 int cnt = of_get_child_count(node);
254 int error;
255
256 if (!num_leds || !cnt)
257 return 0;
258
259 if (cnt > num_leds)
260 return -EINVAL;
261
262 led = devm_kcalloc(dev, cnt, sizeof(struct cap11xx_led), GFP_KERNEL);
263 if (!led)
264 return -ENOMEM;
265
266 priv->leds = led;
267
268 error = regmap_update_bits(priv->regmap,
269 CAP11XX_REG_LED_OUTPUT_CONTROL, 0xff, 0);
270 if (error)
271 return error;
272
273 error = regmap_update_bits(priv->regmap, CAP11XX_REG_LED_DUTY_CYCLE_4,
274 CAP11XX_REG_LED_DUTY_MAX_MASK,
275 CAP11XX_REG_LED_DUTY_MAX_VALUE <<
276 CAP11XX_REG_LED_DUTY_MAX_MASK_SHIFT);
277 if (error)
278 return error;
279
280 for_each_child_of_node(node, child) {
281 u32 reg;
282
283 led->cdev.name =
284 of_get_property(child, "label", NULL) ? : child->name;
285 led->cdev.default_trigger =
286 of_get_property(child, "linux,default-trigger", NULL);
287 led->cdev.flags = 0;
288 led->cdev.brightness_set_blocking = cap11xx_led_set;
289 led->cdev.max_brightness = 1;
290 led->cdev.brightness = LED_OFF;
291
292 error = of_property_read_u32(child, "reg", ®);
293 if (error != 0 || reg >= num_leds) {
294 of_node_put(child);
295 return -EINVAL;
296 }
297
298 led->reg = reg;
299 led->priv = priv;
300
301 error = devm_led_classdev_register(dev, &led->cdev);
302 if (error) {
303 of_node_put(child);
304 return error;
305 }
306
307 priv->num_leds++;
308 led++;
309 }
310
311 return 0;
312}
313#else
314static int cap11xx_init_leds(struct device *dev,
315 struct cap11xx_priv *priv, int num_leds)
316{
317 return 0;
318}
319#endif
320
321static int cap11xx_i2c_probe(struct i2c_client *i2c_client,
322 const struct i2c_device_id *id)
323{
324 struct device *dev = &i2c_client->dev;
325 struct cap11xx_priv *priv;
326 struct device_node *node;
327 const struct cap11xx_hw_model *cap;
328 int i, error, irq, gain = 0;
329 unsigned int val, rev;
330 u32 gain32;
331
332 if (id->driver_data >= ARRAY_SIZE(cap11xx_devices)) {
333 dev_err(dev, "Invalid device ID %lu\n", id->driver_data);
334 return -EINVAL;
335 }
336
337 cap = &cap11xx_devices[id->driver_data];
338 if (!cap || !cap->num_channels) {
339 dev_err(dev, "Invalid device configuration\n");
340 return -EINVAL;
341 }
342
343 priv = devm_kzalloc(dev,
344 struct_size(priv, keycodes, cap->num_channels),
345 GFP_KERNEL);
346 if (!priv)
347 return -ENOMEM;
348
349 priv->regmap = devm_regmap_init_i2c(i2c_client, &cap11xx_regmap_config);
350 if (IS_ERR(priv->regmap))
351 return PTR_ERR(priv->regmap);
352
353 error = regmap_read(priv->regmap, CAP11XX_REG_PRODUCT_ID, &val);
354 if (error)
355 return error;
356
357 if (val != cap->product_id) {
358 dev_err(dev, "Product ID: Got 0x%02x, expected 0x%02x\n",
359 val, cap->product_id);
360 return -ENXIO;
361 }
362
363 error = regmap_read(priv->regmap, CAP11XX_REG_MANUFACTURER_ID, &val);
364 if (error)
365 return error;
366
367 if (val != CAP11XX_MANUFACTURER_ID) {
368 dev_err(dev, "Manufacturer ID: Got 0x%02x, expected 0x%02x\n",
369 val, CAP11XX_MANUFACTURER_ID);
370 return -ENXIO;
371 }
372
373 error = regmap_read(priv->regmap, CAP11XX_REG_REVISION, &rev);
374 if (error < 0)
375 return error;
376
377 dev_info(dev, "CAP11XX detected, revision 0x%02x\n", rev);
378 node = dev->of_node;
379
380 if (!of_property_read_u32(node, "microchip,sensor-gain", &gain32)) {
381 if (is_power_of_2(gain32) && gain32 <= 8)
382 gain = ilog2(gain32);
383 else
384 dev_err(dev, "Invalid sensor-gain value %d\n", gain32);
385 }
386
387 if (of_property_read_bool(node, "microchip,irq-active-high")) {
388 error = regmap_update_bits(priv->regmap, CAP11XX_REG_CONFIG2,
389 CAP11XX_REG_CONFIG2_ALT_POL, 0);
390 if (error)
391 return error;
392 }
393
394 /* Provide some useful defaults */
395 for (i = 0; i < cap->num_channels; i++)
396 priv->keycodes[i] = KEY_A + i;
397
398 of_property_read_u32_array(node, "linux,keycodes",
399 priv->keycodes, cap->num_channels);
400
401 error = regmap_update_bits(priv->regmap, CAP11XX_REG_MAIN_CONTROL,
402 CAP11XX_REG_MAIN_CONTROL_GAIN_MASK,
403 gain << CAP11XX_REG_MAIN_CONTROL_GAIN_SHIFT);
404 if (error)
405 return error;
406
407 /* Disable autorepeat. The Linux input system has its own handling. */
408 error = regmap_write(priv->regmap, CAP11XX_REG_REPEAT_RATE, 0);
409 if (error)
410 return error;
411
412 priv->idev = devm_input_allocate_device(dev);
413 if (!priv->idev)
414 return -ENOMEM;
415
416 priv->idev->name = "CAP11XX capacitive touch sensor";
417 priv->idev->id.bustype = BUS_I2C;
418 priv->idev->evbit[0] = BIT_MASK(EV_KEY);
419
420 if (of_property_read_bool(node, "autorepeat"))
421 __set_bit(EV_REP, priv->idev->evbit);
422
423 for (i = 0; i < cap->num_channels; i++)
424 __set_bit(priv->keycodes[i], priv->idev->keybit);
425
426 __clear_bit(KEY_RESERVED, priv->idev->keybit);
427
428 priv->idev->keycode = priv->keycodes;
429 priv->idev->keycodesize = sizeof(priv->keycodes[0]);
430 priv->idev->keycodemax = cap->num_channels;
431
432 priv->idev->id.vendor = CAP11XX_MANUFACTURER_ID;
433 priv->idev->id.product = cap->product_id;
434 priv->idev->id.version = rev;
435
436 priv->idev->open = cap11xx_input_open;
437 priv->idev->close = cap11xx_input_close;
438
439 error = cap11xx_init_leds(dev, priv, cap->num_leds);
440 if (error)
441 return error;
442
443 input_set_drvdata(priv->idev, priv);
444
445 /*
446 * Put the device in deep sleep mode for now.
447 * ->open() will bring it back once the it is actually needed.
448 */
449 cap11xx_set_sleep(priv, true);
450
451 error = input_register_device(priv->idev);
452 if (error)
453 return error;
454
455 irq = irq_of_parse_and_map(node, 0);
456 if (!irq) {
457 dev_err(dev, "Unable to parse or map IRQ\n");
458 return -ENXIO;
459 }
460
461 error = devm_request_threaded_irq(dev, irq, NULL, cap11xx_thread_func,
462 IRQF_ONESHOT, dev_name(dev), priv);
463 if (error)
464 return error;
465
466 return 0;
467}
468
469static const struct of_device_id cap11xx_dt_ids[] = {
470 { .compatible = "microchip,cap1106", },
471 { .compatible = "microchip,cap1126", },
472 { .compatible = "microchip,cap1188", },
473 {}
474};
475MODULE_DEVICE_TABLE(of, cap11xx_dt_ids);
476
477static const struct i2c_device_id cap11xx_i2c_ids[] = {
478 { "cap1106", CAP1106 },
479 { "cap1126", CAP1126 },
480 { "cap1188", CAP1188 },
481 {}
482};
483MODULE_DEVICE_TABLE(i2c, cap11xx_i2c_ids);
484
485static struct i2c_driver cap11xx_i2c_driver = {
486 .driver = {
487 .name = "cap11xx",
488 .of_match_table = cap11xx_dt_ids,
489 },
490 .id_table = cap11xx_i2c_ids,
491 .probe = cap11xx_i2c_probe,
492};
493
494module_i2c_driver(cap11xx_i2c_driver);
495
496MODULE_DESCRIPTION("Microchip CAP11XX driver");
497MODULE_AUTHOR("Daniel Mack <linux@zonque.org>");
498MODULE_LICENSE("GPL v2");