1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Access to GPIOs on TWL4030/TPS659x0 chips
4 *
5 * Copyright (C) 2006-2007 Texas Instruments, Inc.
6 * Copyright (C) 2006 MontaVista Software, Inc.
7 *
8 * Code re-arranged and cleaned up by:
9 * Syed Mohammed Khasim <x0khasim@ti.com>
10 *
11 * Initial Code:
12 * Andy Lowe / Nishanth Menon
13 */
14
15 #include <linux/module.h>
16 #include <linux/init.h>
17 #include <linux/interrupt.h>
18 #include <linux/kthread.h>
19 #include <linux/irq.h>
20 #include <linux/gpio/machine.h>
21 #include <linux/gpio/driver.h>
22 #include <linux/gpio/consumer.h>
23 #include <linux/platform_device.h>
24 #include <linux/of.h>
25 #include <linux/irqdomain.h>
26
27 #include <linux/mfd/twl.h>
28
29 /*
30 * The GPIO "subchip" supports 18 GPIOs which can be configured as
31 * inputs or outputs, with pullups or pulldowns on each pin. Each
32 * GPIO can trigger interrupts on either or both edges.
33 *
34 * GPIO interrupts can be fed to either of two IRQ lines; this is
35 * intended to support multiple hosts.
36 *
37 * There are also two LED pins used sometimes as output-only GPIOs.
38 */
39
40 /* genirq interfaces are not available to modules */
41 #ifdef MODULE
42 #define is_module() true
43 #else
44 #define is_module() false
45 #endif
46
47 /* GPIO_CTRL Fields */
48 #define MASK_GPIO_CTRL_GPIO0CD1 BIT(0)
49 #define MASK_GPIO_CTRL_GPIO1CD2 BIT(1)
50 #define MASK_GPIO_CTRL_GPIO_ON BIT(2)
51
52 /* Mask for GPIO registers when aggregated into a 32-bit integer */
53 #define GPIO_32_MASK 0x0003ffff
54
55 struct gpio_twl4030_priv {
56 struct gpio_chip gpio_chip;
57 struct mutex mutex;
58 int irq_base;
59
60 /* Bitfields for state caching */
61 unsigned int usage_count;
62 unsigned int direction;
63 unsigned int out_state;
64 };
65
66 /*----------------------------------------------------------------------*/
67
68 /*
69 * To configure TWL4030 GPIO module registers
70 */
gpio_twl4030_write(u8 address,u8 data)71 static inline int gpio_twl4030_write(u8 address, u8 data)
72 {
73 return twl_i2c_write_u8(TWL4030_MODULE_GPIO, data, address);
74 }
75
76 /*----------------------------------------------------------------------*/
77
78 /*
79 * LED register offsets from TWL_MODULE_LED base
80 * PWMs A and B are dedicated to LEDs A and B, respectively.
81 */
82
83 #define TWL4030_LED_LEDEN_REG 0x00
84 #define TWL4030_PWMAON_REG 0x01
85 #define TWL4030_PWMAOFF_REG 0x02
86 #define TWL4030_PWMBON_REG 0x03
87 #define TWL4030_PWMBOFF_REG 0x04
88
89 /* LEDEN bits */
90 #define LEDEN_LEDAON BIT(0)
91 #define LEDEN_LEDBON BIT(1)
92 #define LEDEN_LEDAEXT BIT(2)
93 #define LEDEN_LEDBEXT BIT(3)
94 #define LEDEN_LEDAPWM BIT(4)
95 #define LEDEN_LEDBPWM BIT(5)
96 #define LEDEN_PWM_LENGTHA BIT(6)
97 #define LEDEN_PWM_LENGTHB BIT(7)
98
99 #define PWMxON_LENGTH BIT(7)
100
101 /*----------------------------------------------------------------------*/
102
103 /*
104 * To read a TWL4030 GPIO module register
105 */
gpio_twl4030_read(u8 address)106 static inline int gpio_twl4030_read(u8 address)
107 {
108 u8 data;
109 int ret = 0;
110
111 ret = twl_i2c_read_u8(TWL4030_MODULE_GPIO, &data, address);
112 return (ret < 0) ? ret : data;
113 }
114
115 /*----------------------------------------------------------------------*/
116
117 static u8 cached_leden;
118
119 /* The LED lines are open drain outputs ... a FET pulls to GND, so an
120 * external pullup is needed. We could also expose the integrated PWM
121 * as a LED brightness control; we initialize it as "always on".
122 */
twl4030_led_set_value(int led,int value)123 static void twl4030_led_set_value(int led, int value)
124 {
125 u8 mask = LEDEN_LEDAON | LEDEN_LEDAPWM;
126
127 if (led)
128 mask <<= 1;
129
130 if (value)
131 cached_leden &= ~mask;
132 else
133 cached_leden |= mask;
134
135 WARN_ON_ONCE(twl_i2c_write_u8(TWL4030_MODULE_LED, cached_leden,
136 TWL4030_LED_LEDEN_REG));
137 }
138
twl4030_set_gpio_direction(int gpio,int is_input)139 static int twl4030_set_gpio_direction(int gpio, int is_input)
140 {
141 u8 d_bnk = gpio >> 3;
142 u8 d_msk = BIT(gpio & 0x7);
143 u8 reg = 0;
144 u8 base = REG_GPIODATADIR1 + d_bnk;
145 int ret = 0;
146
147 ret = gpio_twl4030_read(base);
148 if (ret >= 0) {
149 if (is_input)
150 reg = ret & ~d_msk;
151 else
152 reg = ret | d_msk;
153
154 ret = gpio_twl4030_write(base, reg);
155 }
156 return ret;
157 }
158
twl4030_get_gpio_direction(int gpio)159 static int twl4030_get_gpio_direction(int gpio)
160 {
161 u8 d_bnk = gpio >> 3;
162 u8 d_msk = BIT(gpio & 0x7);
163 u8 base = REG_GPIODATADIR1 + d_bnk;
164 int ret = 0;
165
166 ret = gpio_twl4030_read(base);
167 if (ret < 0)
168 return ret;
169
170 if (ret & d_msk)
171 return GPIO_LINE_DIRECTION_OUT;
172
173 return GPIO_LINE_DIRECTION_IN;
174 }
175
twl4030_set_gpio_dataout(int gpio,int enable)176 static int twl4030_set_gpio_dataout(int gpio, int enable)
177 {
178 u8 d_bnk = gpio >> 3;
179 u8 d_msk = BIT(gpio & 0x7);
180 u8 base = 0;
181
182 if (enable)
183 base = REG_SETGPIODATAOUT1 + d_bnk;
184 else
185 base = REG_CLEARGPIODATAOUT1 + d_bnk;
186
187 return gpio_twl4030_write(base, d_msk);
188 }
189
twl4030_get_gpio_datain(int gpio)190 static int twl4030_get_gpio_datain(int gpio)
191 {
192 u8 d_bnk = gpio >> 3;
193 u8 d_off = gpio & 0x7;
194 u8 base = 0;
195 int ret = 0;
196
197 base = REG_GPIODATAIN1 + d_bnk;
198 ret = gpio_twl4030_read(base);
199 if (ret > 0)
200 ret = (ret >> d_off) & 0x1;
201
202 return ret;
203 }
204
205 /*----------------------------------------------------------------------*/
206
twl_request(struct gpio_chip * chip,unsigned offset)207 static int twl_request(struct gpio_chip *chip, unsigned offset)
208 {
209 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
210 int status = 0;
211
212 mutex_lock(&priv->mutex);
213
214 /* Support the two LED outputs as output-only GPIOs. */
215 if (offset >= TWL4030_GPIO_MAX) {
216 u8 ledclr_mask = LEDEN_LEDAON | LEDEN_LEDAEXT
217 | LEDEN_LEDAPWM | LEDEN_PWM_LENGTHA;
218 u8 reg = TWL4030_PWMAON_REG;
219
220 offset -= TWL4030_GPIO_MAX;
221 if (offset) {
222 ledclr_mask <<= 1;
223 reg = TWL4030_PWMBON_REG;
224 }
225
226 /* initialize PWM to always-drive */
227 /* Configure PWM OFF register first */
228 status = twl_i2c_write_u8(TWL4030_MODULE_LED, 0x7f, reg + 1);
229 if (status < 0)
230 goto done;
231
232 /* Followed by PWM ON register */
233 status = twl_i2c_write_u8(TWL4030_MODULE_LED, 0x7f, reg);
234 if (status < 0)
235 goto done;
236
237 /* init LED to not-driven (high) */
238 status = twl_i2c_read_u8(TWL4030_MODULE_LED, &cached_leden,
239 TWL4030_LED_LEDEN_REG);
240 if (status < 0)
241 goto done;
242 cached_leden &= ~ledclr_mask;
243 status = twl_i2c_write_u8(TWL4030_MODULE_LED, cached_leden,
244 TWL4030_LED_LEDEN_REG);
245 if (status < 0)
246 goto done;
247
248 status = 0;
249 goto done;
250 }
251
252 /* on first use, turn GPIO module "on" */
253 if (!priv->usage_count) {
254 struct twl4030_gpio_platform_data *pdata;
255 u8 value = MASK_GPIO_CTRL_GPIO_ON;
256
257 /* optionally have the first two GPIOs switch vMMC1
258 * and vMMC2 power supplies based on card presence.
259 */
260 pdata = dev_get_platdata(chip->parent);
261 if (pdata)
262 value |= pdata->mmc_cd & 0x03;
263
264 status = gpio_twl4030_write(REG_GPIO_CTRL, value);
265 }
266
267 done:
268 if (!status)
269 priv->usage_count |= BIT(offset);
270
271 mutex_unlock(&priv->mutex);
272 return status;
273 }
274
twl_free(struct gpio_chip * chip,unsigned offset)275 static void twl_free(struct gpio_chip *chip, unsigned offset)
276 {
277 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
278
279 mutex_lock(&priv->mutex);
280 if (offset >= TWL4030_GPIO_MAX) {
281 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, 1);
282 goto out;
283 }
284
285 priv->usage_count &= ~BIT(offset);
286
287 /* on last use, switch off GPIO module */
288 if (!priv->usage_count)
289 gpio_twl4030_write(REG_GPIO_CTRL, 0x0);
290
291 out:
292 mutex_unlock(&priv->mutex);
293 }
294
twl_direction_in(struct gpio_chip * chip,unsigned offset)295 static int twl_direction_in(struct gpio_chip *chip, unsigned offset)
296 {
297 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
298 int ret;
299
300 mutex_lock(&priv->mutex);
301 if (offset < TWL4030_GPIO_MAX)
302 ret = twl4030_set_gpio_direction(offset, 1);
303 else
304 ret = -EINVAL; /* LED outputs can't be set as input */
305
306 if (!ret)
307 priv->direction &= ~BIT(offset);
308
309 mutex_unlock(&priv->mutex);
310
311 return ret;
312 }
313
twl_get(struct gpio_chip * chip,unsigned offset)314 static int twl_get(struct gpio_chip *chip, unsigned offset)
315 {
316 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
317 int ret;
318 int status = 0;
319
320 mutex_lock(&priv->mutex);
321 if (!(priv->usage_count & BIT(offset))) {
322 ret = -EPERM;
323 goto out;
324 }
325
326 if (priv->direction & BIT(offset))
327 status = priv->out_state & BIT(offset);
328 else
329 status = twl4030_get_gpio_datain(offset);
330
331 ret = (status < 0) ? status : !!status;
332 out:
333 mutex_unlock(&priv->mutex);
334 return ret;
335 }
336
twl_set(struct gpio_chip * chip,unsigned offset,int value)337 static void twl_set(struct gpio_chip *chip, unsigned offset, int value)
338 {
339 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
340
341 mutex_lock(&priv->mutex);
342 if (offset < TWL4030_GPIO_MAX)
343 twl4030_set_gpio_dataout(offset, value);
344 else
345 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, value);
346
347 if (value)
348 priv->out_state |= BIT(offset);
349 else
350 priv->out_state &= ~BIT(offset);
351
352 mutex_unlock(&priv->mutex);
353 }
354
twl_direction_out(struct gpio_chip * chip,unsigned offset,int value)355 static int twl_direction_out(struct gpio_chip *chip, unsigned offset, int value)
356 {
357 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
358 int ret = 0;
359
360 mutex_lock(&priv->mutex);
361 if (offset < TWL4030_GPIO_MAX) {
362 ret = twl4030_set_gpio_direction(offset, 0);
363 if (ret) {
364 mutex_unlock(&priv->mutex);
365 return ret;
366 }
367 }
368
369 /*
370 * LED gpios i.e. offset >= TWL4030_GPIO_MAX are always output
371 */
372
373 priv->direction |= BIT(offset);
374 mutex_unlock(&priv->mutex);
375
376 twl_set(chip, offset, value);
377
378 return ret;
379 }
380
twl_get_direction(struct gpio_chip * chip,unsigned offset)381 static int twl_get_direction(struct gpio_chip *chip, unsigned offset)
382 {
383 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
384 /*
385 * Default GPIO_LINE_DIRECTION_OUT
386 * LED GPIOs >= TWL4030_GPIO_MAX are always output
387 */
388 int ret = GPIO_LINE_DIRECTION_OUT;
389
390 mutex_lock(&priv->mutex);
391 if (offset < TWL4030_GPIO_MAX) {
392 ret = twl4030_get_gpio_direction(offset);
393 if (ret) {
394 mutex_unlock(&priv->mutex);
395 return ret;
396 }
397 }
398 mutex_unlock(&priv->mutex);
399
400 return ret;
401 }
402
twl_to_irq(struct gpio_chip * chip,unsigned offset)403 static int twl_to_irq(struct gpio_chip *chip, unsigned offset)
404 {
405 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
406
407 return (priv->irq_base && (offset < TWL4030_GPIO_MAX))
408 ? (priv->irq_base + offset)
409 : -EINVAL;
410 }
411
412 static const struct gpio_chip template_chip = {
413 .label = "twl4030",
414 .owner = THIS_MODULE,
415 .request = twl_request,
416 .free = twl_free,
417 .direction_input = twl_direction_in,
418 .direction_output = twl_direction_out,
419 .get_direction = twl_get_direction,
420 .get = twl_get,
421 .set = twl_set,
422 .to_irq = twl_to_irq,
423 .can_sleep = true,
424 };
425
426 /*----------------------------------------------------------------------*/
427
gpio_twl4030_pulls(u32 ups,u32 downs)428 static int gpio_twl4030_pulls(u32 ups, u32 downs)
429 {
430 u8 message[5];
431 unsigned i, gpio_bit;
432
433 /* For most pins, a pulldown was enabled by default.
434 * We should have data that's specific to this board.
435 */
436 for (gpio_bit = 1, i = 0; i < 5; i++) {
437 u8 bit_mask;
438 unsigned j;
439
440 for (bit_mask = 0, j = 0; j < 8; j += 2, gpio_bit <<= 1) {
441 if (ups & gpio_bit)
442 bit_mask |= 1 << (j + 1);
443 else if (downs & gpio_bit)
444 bit_mask |= 1 << (j + 0);
445 }
446 message[i] = bit_mask;
447 }
448
449 return twl_i2c_write(TWL4030_MODULE_GPIO, message,
450 REG_GPIOPUPDCTR1, 5);
451 }
452
gpio_twl4030_debounce(u32 debounce,u8 mmc_cd)453 static int gpio_twl4030_debounce(u32 debounce, u8 mmc_cd)
454 {
455 u8 message[3];
456
457 /* 30 msec of debouncing is always used for MMC card detect,
458 * and is optional for everything else.
459 */
460 message[0] = (debounce & 0xff) | (mmc_cd & 0x03);
461 debounce >>= 8;
462 message[1] = (debounce & 0xff);
463 debounce >>= 8;
464 message[2] = (debounce & 0x03);
465
466 return twl_i2c_write(TWL4030_MODULE_GPIO, message,
467 REG_GPIO_DEBEN1, 3);
468 }
469
of_gpio_twl4030(struct device * dev)470 static struct twl4030_gpio_platform_data *of_gpio_twl4030(struct device *dev)
471 {
472 struct twl4030_gpio_platform_data *omap_twl_info;
473
474 omap_twl_info = devm_kzalloc(dev, sizeof(*omap_twl_info), GFP_KERNEL);
475 if (!omap_twl_info)
476 return NULL;
477
478 omap_twl_info->use_leds = of_property_read_bool(dev->of_node,
479 "ti,use-leds");
480
481 of_property_read_u32(dev->of_node, "ti,debounce",
482 &omap_twl_info->debounce);
483 of_property_read_u32(dev->of_node, "ti,mmc-cd",
484 (u32 *)&omap_twl_info->mmc_cd);
485 of_property_read_u32(dev->of_node, "ti,pullups",
486 &omap_twl_info->pullups);
487 of_property_read_u32(dev->of_node, "ti,pulldowns",
488 &omap_twl_info->pulldowns);
489
490 return omap_twl_info;
491 }
492
493 /* Called from the registered devm action */
gpio_twl4030_power_off_action(void * data)494 static void gpio_twl4030_power_off_action(void *data)
495 {
496 struct gpio_desc *d = data;
497
498 gpiod_unexport(d);
499 gpiochip_free_own_desc(d);
500 }
501
gpio_twl4030_probe(struct platform_device * pdev)502 static int gpio_twl4030_probe(struct platform_device *pdev)
503 {
504 struct twl4030_gpio_platform_data *pdata;
505 struct device_node *node = pdev->dev.of_node;
506 struct gpio_twl4030_priv *priv;
507 int ret, irq_base;
508
509 priv = devm_kzalloc(&pdev->dev, sizeof(struct gpio_twl4030_priv),
510 GFP_KERNEL);
511 if (!priv)
512 return -ENOMEM;
513
514 /* maybe setup IRQs */
515 if (is_module()) {
516 dev_err(&pdev->dev, "can't dispatch IRQs from modules\n");
517 goto no_irqs;
518 }
519
520 irq_base = devm_irq_alloc_descs(&pdev->dev, -1,
521 0, TWL4030_GPIO_MAX, 0);
522 if (irq_base < 0) {
523 dev_err(&pdev->dev, "Failed to alloc irq_descs\n");
524 return irq_base;
525 }
526
527 irq_domain_add_legacy(node, TWL4030_GPIO_MAX, irq_base, 0,
528 &irq_domain_simple_ops, NULL);
529
530 ret = twl4030_sih_setup(&pdev->dev, TWL4030_MODULE_GPIO, irq_base);
531 if (ret < 0)
532 return ret;
533
534 priv->irq_base = irq_base;
535
536 no_irqs:
537 priv->gpio_chip = template_chip;
538 priv->gpio_chip.base = -1;
539 priv->gpio_chip.ngpio = TWL4030_GPIO_MAX;
540 priv->gpio_chip.parent = &pdev->dev;
541
542 mutex_init(&priv->mutex);
543
544 pdata = of_gpio_twl4030(&pdev->dev);
545 if (pdata == NULL) {
546 dev_err(&pdev->dev, "Platform data is missing\n");
547 return -ENXIO;
548 }
549
550 /*
551 * NOTE: boards may waste power if they don't set pullups
552 * and pulldowns correctly ... default for non-ULPI pins is
553 * pulldown, and some other pins may have external pullups
554 * or pulldowns. Careful!
555 */
556 ret = gpio_twl4030_pulls(pdata->pullups, pdata->pulldowns);
557 if (ret)
558 dev_dbg(&pdev->dev, "pullups %.05x %.05x --> %d\n",
559 pdata->pullups, pdata->pulldowns, ret);
560
561 ret = gpio_twl4030_debounce(pdata->debounce, pdata->mmc_cd);
562 if (ret)
563 dev_dbg(&pdev->dev, "debounce %.03x %.01x --> %d\n",
564 pdata->debounce, pdata->mmc_cd, ret);
565
566 /*
567 * NOTE: we assume VIBRA_CTL.VIBRA_EN, in MODULE_AUDIO_VOICE,
568 * is (still) clear if use_leds is set.
569 */
570 if (pdata->use_leds)
571 priv->gpio_chip.ngpio += 2;
572
573 ret = devm_gpiochip_add_data(&pdev->dev, &priv->gpio_chip, priv);
574 if (ret < 0) {
575 dev_err(&pdev->dev, "could not register gpiochip, %d\n", ret);
576 priv->gpio_chip.ngpio = 0;
577 return ret;
578 }
579
580 /*
581 * Special quirk for the OMAP3 to hog and export a WLAN power
582 * GPIO.
583 */
584 if (IS_ENABLED(CONFIG_ARCH_OMAP3) &&
585 of_machine_is_compatible("compulab,omap3-sbc-t3730")) {
586 struct gpio_desc *d;
587
588 d = gpiochip_request_own_desc(&priv->gpio_chip,
589 2, "wlan pwr",
590 GPIO_ACTIVE_HIGH,
591 GPIOD_OUT_HIGH);
592 if (IS_ERR(d))
593 return dev_err_probe(&pdev->dev, PTR_ERR(d),
594 "unable to hog wlan pwr GPIO\n");
595
596 gpiod_export(d, 0);
597
598 ret = devm_add_action_or_reset(&pdev->dev, gpio_twl4030_power_off_action, d);
599 if (ret)
600 return dev_err_probe(&pdev->dev, ret,
601 "failed to install power off handler\n");
602
603 }
604
605 return 0;
606 }
607
608 static const struct of_device_id twl_gpio_match[] = {
609 { .compatible = "ti,twl4030-gpio", },
610 { },
611 };
612 MODULE_DEVICE_TABLE(of, twl_gpio_match);
613
614 /* Note: this hardware lives inside an I2C-based multi-function device. */
615 MODULE_ALIAS("platform:twl4030_gpio");
616
617 static struct platform_driver gpio_twl4030_driver = {
618 .driver = {
619 .name = "twl4030_gpio",
620 .of_match_table = twl_gpio_match,
621 },
622 .probe = gpio_twl4030_probe,
623 };
624
gpio_twl4030_init(void)625 static int __init gpio_twl4030_init(void)
626 {
627 return platform_driver_register(&gpio_twl4030_driver);
628 }
629 subsys_initcall(gpio_twl4030_init);
630
gpio_twl4030_exit(void)631 static void __exit gpio_twl4030_exit(void)
632 {
633 platform_driver_unregister(&gpio_twl4030_driver);
634 }
635 module_exit(gpio_twl4030_exit);
636
637 MODULE_AUTHOR("Texas Instruments, Inc.");
638 MODULE_DESCRIPTION("GPIO interface for TWL4030");
639 MODULE_LICENSE("GPL");
640