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/driver.h>
21#include <linux/platform_device.h>
22#include <linux/of.h>
23#include <linux/irqdomain.h>
24
25#include <linux/mfd/twl.h>
26
27/*
28 * The GPIO "subchip" supports 18 GPIOs which can be configured as
29 * inputs or outputs, with pullups or pulldowns on each pin. Each
30 * GPIO can trigger interrupts on either or both edges.
31 *
32 * GPIO interrupts can be fed to either of two IRQ lines; this is
33 * intended to support multiple hosts.
34 *
35 * There are also two LED pins used sometimes as output-only GPIOs.
36 */
37
38/* genirq interfaces are not available to modules */
39#ifdef MODULE
40#define is_module() true
41#else
42#define is_module() false
43#endif
44
45/* GPIO_CTRL Fields */
46#define MASK_GPIO_CTRL_GPIO0CD1 BIT(0)
47#define MASK_GPIO_CTRL_GPIO1CD2 BIT(1)
48#define MASK_GPIO_CTRL_GPIO_ON BIT(2)
49
50/* Mask for GPIO registers when aggregated into a 32-bit integer */
51#define GPIO_32_MASK 0x0003ffff
52
53struct gpio_twl4030_priv {
54 struct gpio_chip gpio_chip;
55 struct mutex mutex;
56 int irq_base;
57
58 /* Bitfields for state caching */
59 unsigned int usage_count;
60 unsigned int direction;
61 unsigned int out_state;
62};
63
64/*----------------------------------------------------------------------*/
65
66/*
67 * To configure TWL4030 GPIO module registers
68 */
69static inline int gpio_twl4030_write(u8 address, u8 data)
70{
71 return twl_i2c_write_u8(TWL4030_MODULE_GPIO, data, address);
72}
73
74/*----------------------------------------------------------------------*/
75
76/*
77 * LED register offsets from TWL_MODULE_LED base
78 * PWMs A and B are dedicated to LEDs A and B, respectively.
79 */
80
81#define TWL4030_LED_LEDEN_REG 0x00
82#define TWL4030_PWMAON_REG 0x01
83#define TWL4030_PWMAOFF_REG 0x02
84#define TWL4030_PWMBON_REG 0x03
85#define TWL4030_PWMBOFF_REG 0x04
86
87/* LEDEN bits */
88#define LEDEN_LEDAON BIT(0)
89#define LEDEN_LEDBON BIT(1)
90#define LEDEN_LEDAEXT BIT(2)
91#define LEDEN_LEDBEXT BIT(3)
92#define LEDEN_LEDAPWM BIT(4)
93#define LEDEN_LEDBPWM BIT(5)
94#define LEDEN_PWM_LENGTHA BIT(6)
95#define LEDEN_PWM_LENGTHB BIT(7)
96
97#define PWMxON_LENGTH BIT(7)
98
99/*----------------------------------------------------------------------*/
100
101/*
102 * To read a TWL4030 GPIO module register
103 */
104static inline int gpio_twl4030_read(u8 address)
105{
106 u8 data;
107 int ret = 0;
108
109 ret = twl_i2c_read_u8(TWL4030_MODULE_GPIO, &data, address);
110 return (ret < 0) ? ret : data;
111}
112
113/*----------------------------------------------------------------------*/
114
115static u8 cached_leden;
116
117/* The LED lines are open drain outputs ... a FET pulls to GND, so an
118 * external pullup is needed. We could also expose the integrated PWM
119 * as a LED brightness control; we initialize it as "always on".
120 */
121static void twl4030_led_set_value(int led, int value)
122{
123 u8 mask = LEDEN_LEDAON | LEDEN_LEDAPWM;
124
125 if (led)
126 mask <<= 1;
127
128 if (value)
129 cached_leden &= ~mask;
130 else
131 cached_leden |= mask;
132
133 WARN_ON_ONCE(twl_i2c_write_u8(TWL4030_MODULE_LED, cached_leden,
134 TWL4030_LED_LEDEN_REG));
135}
136
137static int twl4030_set_gpio_direction(int gpio, int is_input)
138{
139 u8 d_bnk = gpio >> 3;
140 u8 d_msk = BIT(gpio & 0x7);
141 u8 reg = 0;
142 u8 base = REG_GPIODATADIR1 + d_bnk;
143 int ret = 0;
144
145 ret = gpio_twl4030_read(base);
146 if (ret >= 0) {
147 if (is_input)
148 reg = ret & ~d_msk;
149 else
150 reg = ret | d_msk;
151
152 ret = gpio_twl4030_write(base, reg);
153 }
154 return ret;
155}
156
157static int twl4030_get_gpio_direction(int gpio)
158{
159 u8 d_bnk = gpio >> 3;
160 u8 d_msk = BIT(gpio & 0x7);
161 u8 base = REG_GPIODATADIR1 + d_bnk;
162 int ret = 0;
163
164 ret = gpio_twl4030_read(base);
165 if (ret < 0)
166 return ret;
167
168 /* 1 = output, but gpiolib semantics are inverse so invert */
169 ret = !(ret & d_msk);
170
171 return ret;
172}
173
174static int twl4030_set_gpio_dataout(int gpio, int enable)
175{
176 u8 d_bnk = gpio >> 3;
177 u8 d_msk = BIT(gpio & 0x7);
178 u8 base = 0;
179
180 if (enable)
181 base = REG_SETGPIODATAOUT1 + d_bnk;
182 else
183 base = REG_CLEARGPIODATAOUT1 + d_bnk;
184
185 return gpio_twl4030_write(base, d_msk);
186}
187
188static int twl4030_get_gpio_datain(int gpio)
189{
190 u8 d_bnk = gpio >> 3;
191 u8 d_off = gpio & 0x7;
192 u8 base = 0;
193 int ret = 0;
194
195 base = REG_GPIODATAIN1 + d_bnk;
196 ret = gpio_twl4030_read(base);
197 if (ret > 0)
198 ret = (ret >> d_off) & 0x1;
199
200 return ret;
201}
202
203/*----------------------------------------------------------------------*/
204
205static int twl_request(struct gpio_chip *chip, unsigned offset)
206{
207 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
208 int status = 0;
209
210 mutex_lock(&priv->mutex);
211
212 /* Support the two LED outputs as output-only GPIOs. */
213 if (offset >= TWL4030_GPIO_MAX) {
214 u8 ledclr_mask = LEDEN_LEDAON | LEDEN_LEDAEXT
215 | LEDEN_LEDAPWM | LEDEN_PWM_LENGTHA;
216 u8 reg = TWL4030_PWMAON_REG;
217
218 offset -= TWL4030_GPIO_MAX;
219 if (offset) {
220 ledclr_mask <<= 1;
221 reg = TWL4030_PWMBON_REG;
222 }
223
224 /* initialize PWM to always-drive */
225 /* Configure PWM OFF register first */
226 status = twl_i2c_write_u8(TWL4030_MODULE_LED, 0x7f, reg + 1);
227 if (status < 0)
228 goto done;
229
230 /* Followed by PWM ON register */
231 status = twl_i2c_write_u8(TWL4030_MODULE_LED, 0x7f, reg);
232 if (status < 0)
233 goto done;
234
235 /* init LED to not-driven (high) */
236 status = twl_i2c_read_u8(TWL4030_MODULE_LED, &cached_leden,
237 TWL4030_LED_LEDEN_REG);
238 if (status < 0)
239 goto done;
240 cached_leden &= ~ledclr_mask;
241 status = twl_i2c_write_u8(TWL4030_MODULE_LED, cached_leden,
242 TWL4030_LED_LEDEN_REG);
243 if (status < 0)
244 goto done;
245
246 status = 0;
247 goto done;
248 }
249
250 /* on first use, turn GPIO module "on" */
251 if (!priv->usage_count) {
252 struct twl4030_gpio_platform_data *pdata;
253 u8 value = MASK_GPIO_CTRL_GPIO_ON;
254
255 /* optionally have the first two GPIOs switch vMMC1
256 * and vMMC2 power supplies based on card presence.
257 */
258 pdata = dev_get_platdata(chip->parent);
259 if (pdata)
260 value |= pdata->mmc_cd & 0x03;
261
262 status = gpio_twl4030_write(REG_GPIO_CTRL, value);
263 }
264
265done:
266 if (!status)
267 priv->usage_count |= BIT(offset);
268
269 mutex_unlock(&priv->mutex);
270 return status;
271}
272
273static void twl_free(struct gpio_chip *chip, unsigned offset)
274{
275 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
276
277 mutex_lock(&priv->mutex);
278 if (offset >= TWL4030_GPIO_MAX) {
279 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, 1);
280 goto out;
281 }
282
283 priv->usage_count &= ~BIT(offset);
284
285 /* on last use, switch off GPIO module */
286 if (!priv->usage_count)
287 gpio_twl4030_write(REG_GPIO_CTRL, 0x0);
288
289out:
290 mutex_unlock(&priv->mutex);
291}
292
293static int twl_direction_in(struct gpio_chip *chip, unsigned offset)
294{
295 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
296 int ret;
297
298 mutex_lock(&priv->mutex);
299 if (offset < TWL4030_GPIO_MAX)
300 ret = twl4030_set_gpio_direction(offset, 1);
301 else
302 ret = -EINVAL; /* LED outputs can't be set as input */
303
304 if (!ret)
305 priv->direction &= ~BIT(offset);
306
307 mutex_unlock(&priv->mutex);
308
309 return ret;
310}
311
312static int twl_get(struct gpio_chip *chip, unsigned offset)
313{
314 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
315 int ret;
316 int status = 0;
317
318 mutex_lock(&priv->mutex);
319 if (!(priv->usage_count & BIT(offset))) {
320 ret = -EPERM;
321 goto out;
322 }
323
324 if (priv->direction & BIT(offset))
325 status = priv->out_state & BIT(offset);
326 else
327 status = twl4030_get_gpio_datain(offset);
328
329 ret = (status < 0) ? status : !!status;
330out:
331 mutex_unlock(&priv->mutex);
332 return ret;
333}
334
335static void twl_set(struct gpio_chip *chip, unsigned offset, int value)
336{
337 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
338
339 mutex_lock(&priv->mutex);
340 if (offset < TWL4030_GPIO_MAX)
341 twl4030_set_gpio_dataout(offset, value);
342 else
343 twl4030_led_set_value(offset - TWL4030_GPIO_MAX, value);
344
345 if (value)
346 priv->out_state |= BIT(offset);
347 else
348 priv->out_state &= ~BIT(offset);
349
350 mutex_unlock(&priv->mutex);
351}
352
353static int twl_direction_out(struct gpio_chip *chip, unsigned offset, int value)
354{
355 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
356 int ret = 0;
357
358 mutex_lock(&priv->mutex);
359 if (offset < TWL4030_GPIO_MAX) {
360 ret = twl4030_set_gpio_direction(offset, 0);
361 if (ret) {
362 mutex_unlock(&priv->mutex);
363 return ret;
364 }
365 }
366
367 /*
368 * LED gpios i.e. offset >= TWL4030_GPIO_MAX are always output
369 */
370
371 priv->direction |= BIT(offset);
372 mutex_unlock(&priv->mutex);
373
374 twl_set(chip, offset, value);
375
376 return ret;
377}
378
379static int twl_get_direction(struct gpio_chip *chip, unsigned offset)
380{
381 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
382 /*
383 * Default 0 = output
384 * LED GPIOs >= TWL4030_GPIO_MAX are always output
385 */
386 int ret = 0;
387
388 mutex_lock(&priv->mutex);
389 if (offset < TWL4030_GPIO_MAX) {
390 ret = twl4030_get_gpio_direction(offset);
391 if (ret) {
392 mutex_unlock(&priv->mutex);
393 return ret;
394 }
395 }
396 mutex_unlock(&priv->mutex);
397
398 return ret;
399}
400
401static int twl_to_irq(struct gpio_chip *chip, unsigned offset)
402{
403 struct gpio_twl4030_priv *priv = gpiochip_get_data(chip);
404
405 return (priv->irq_base && (offset < TWL4030_GPIO_MAX))
406 ? (priv->irq_base + offset)
407 : -EINVAL;
408}
409
410static const struct gpio_chip template_chip = {
411 .label = "twl4030",
412 .owner = THIS_MODULE,
413 .request = twl_request,
414 .free = twl_free,
415 .direction_input = twl_direction_in,
416 .direction_output = twl_direction_out,
417 .get_direction = twl_get_direction,
418 .get = twl_get,
419 .set = twl_set,
420 .to_irq = twl_to_irq,
421 .can_sleep = true,
422};
423
424/*----------------------------------------------------------------------*/
425
426static int gpio_twl4030_pulls(u32 ups, u32 downs)
427{
428 u8 message[5];
429 unsigned i, gpio_bit;
430
431 /* For most pins, a pulldown was enabled by default.
432 * We should have data that's specific to this board.
433 */
434 for (gpio_bit = 1, i = 0; i < 5; i++) {
435 u8 bit_mask;
436 unsigned j;
437
438 for (bit_mask = 0, j = 0; j < 8; j += 2, gpio_bit <<= 1) {
439 if (ups & gpio_bit)
440 bit_mask |= 1 << (j + 1);
441 else if (downs & gpio_bit)
442 bit_mask |= 1 << (j + 0);
443 }
444 message[i] = bit_mask;
445 }
446
447 return twl_i2c_write(TWL4030_MODULE_GPIO, message,
448 REG_GPIOPUPDCTR1, 5);
449}
450
451static int gpio_twl4030_debounce(u32 debounce, u8 mmc_cd)
452{
453 u8 message[3];
454
455 /* 30 msec of debouncing is always used for MMC card detect,
456 * and is optional for everything else.
457 */
458 message[0] = (debounce & 0xff) | (mmc_cd & 0x03);
459 debounce >>= 8;
460 message[1] = (debounce & 0xff);
461 debounce >>= 8;
462 message[2] = (debounce & 0x03);
463
464 return twl_i2c_write(TWL4030_MODULE_GPIO, message,
465 REG_GPIO_DEBEN1, 3);
466}
467
468static int gpio_twl4030_remove(struct platform_device *pdev);
469
470static struct twl4030_gpio_platform_data *of_gpio_twl4030(struct device *dev,
471 struct twl4030_gpio_platform_data *pdata)
472{
473 struct twl4030_gpio_platform_data *omap_twl_info;
474
475 omap_twl_info = devm_kzalloc(dev, sizeof(*omap_twl_info), GFP_KERNEL);
476 if (!omap_twl_info)
477 return NULL;
478
479 if (pdata)
480 *omap_twl_info = *pdata;
481
482 omap_twl_info->use_leds = of_property_read_bool(dev->of_node,
483 "ti,use-leds");
484
485 of_property_read_u32(dev->of_node, "ti,debounce",
486 &omap_twl_info->debounce);
487 of_property_read_u32(dev->of_node, "ti,mmc-cd",
488 (u32 *)&omap_twl_info->mmc_cd);
489 of_property_read_u32(dev->of_node, "ti,pullups",
490 &omap_twl_info->pullups);
491 of_property_read_u32(dev->of_node, "ti,pulldowns",
492 &omap_twl_info->pulldowns);
493
494 return omap_twl_info;
495}
496
497static int gpio_twl4030_probe(struct platform_device *pdev)
498{
499 struct twl4030_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
500 struct device_node *node = pdev->dev.of_node;
501 struct gpio_twl4030_priv *priv;
502 int ret, irq_base;
503
504 priv = devm_kzalloc(&pdev->dev, sizeof(struct gpio_twl4030_priv),
505 GFP_KERNEL);
506 if (!priv)
507 return -ENOMEM;
508
509 /* maybe setup IRQs */
510 if (is_module()) {
511 dev_err(&pdev->dev, "can't dispatch IRQs from modules\n");
512 goto no_irqs;
513 }
514
515 irq_base = devm_irq_alloc_descs(&pdev->dev, -1,
516 0, TWL4030_GPIO_MAX, 0);
517 if (irq_base < 0) {
518 dev_err(&pdev->dev, "Failed to alloc irq_descs\n");
519 return irq_base;
520 }
521
522 irq_domain_add_legacy(node, TWL4030_GPIO_MAX, irq_base, 0,
523 &irq_domain_simple_ops, NULL);
524
525 ret = twl4030_sih_setup(&pdev->dev, TWL4030_MODULE_GPIO, irq_base);
526 if (ret < 0)
527 return ret;
528
529 priv->irq_base = irq_base;
530
531no_irqs:
532 priv->gpio_chip = template_chip;
533 priv->gpio_chip.base = -1;
534 priv->gpio_chip.ngpio = TWL4030_GPIO_MAX;
535 priv->gpio_chip.parent = &pdev->dev;
536
537 mutex_init(&priv->mutex);
538
539 if (node)
540 pdata = of_gpio_twl4030(&pdev->dev, pdata);
541
542 if (pdata == NULL) {
543 dev_err(&pdev->dev, "Platform data is missing\n");
544 return -ENXIO;
545 }
546
547 /*
548 * NOTE: boards may waste power if they don't set pullups
549 * and pulldowns correctly ... default for non-ULPI pins is
550 * pulldown, and some other pins may have external pullups
551 * or pulldowns. Careful!
552 */
553 ret = gpio_twl4030_pulls(pdata->pullups, pdata->pulldowns);
554 if (ret)
555 dev_dbg(&pdev->dev, "pullups %.05x %.05x --> %d\n",
556 pdata->pullups, pdata->pulldowns, ret);
557
558 ret = gpio_twl4030_debounce(pdata->debounce, pdata->mmc_cd);
559 if (ret)
560 dev_dbg(&pdev->dev, "debounce %.03x %.01x --> %d\n",
561 pdata->debounce, pdata->mmc_cd, ret);
562
563 /*
564 * NOTE: we assume VIBRA_CTL.VIBRA_EN, in MODULE_AUDIO_VOICE,
565 * is (still) clear if use_leds is set.
566 */
567 if (pdata->use_leds)
568 priv->gpio_chip.ngpio += 2;
569
570 ret = gpiochip_add_data(&priv->gpio_chip, priv);
571 if (ret < 0) {
572 dev_err(&pdev->dev, "could not register gpiochip, %d\n", ret);
573 priv->gpio_chip.ngpio = 0;
574 gpio_twl4030_remove(pdev);
575 goto out;
576 }
577
578 platform_set_drvdata(pdev, priv);
579
580 if (pdata->setup) {
581 int status;
582
583 status = pdata->setup(&pdev->dev, priv->gpio_chip.base,
584 TWL4030_GPIO_MAX);
585 if (status)
586 dev_dbg(&pdev->dev, "setup --> %d\n", status);
587 }
588
589out:
590 return ret;
591}
592
593/* Cannot use as gpio_twl4030_probe() calls us */
594static int gpio_twl4030_remove(struct platform_device *pdev)
595{
596 struct twl4030_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
597 struct gpio_twl4030_priv *priv = platform_get_drvdata(pdev);
598 int status;
599
600 if (pdata && pdata->teardown) {
601 status = pdata->teardown(&pdev->dev, priv->gpio_chip.base,
602 TWL4030_GPIO_MAX);
603 if (status) {
604 dev_dbg(&pdev->dev, "teardown --> %d\n", status);
605 return status;
606 }
607 }
608
609 gpiochip_remove(&priv->gpio_chip);
610
611 if (is_module())
612 return 0;
613
614 /* REVISIT no support yet for deregistering all the IRQs */
615 WARN_ON(1);
616 return -EIO;
617}
618
619static const struct of_device_id twl_gpio_match[] = {
620 { .compatible = "ti,twl4030-gpio", },
621 { },
622};
623MODULE_DEVICE_TABLE(of, twl_gpio_match);
624
625/* Note: this hardware lives inside an I2C-based multi-function device. */
626MODULE_ALIAS("platform:twl4030_gpio");
627
628static struct platform_driver gpio_twl4030_driver = {
629 .driver = {
630 .name = "twl4030_gpio",
631 .of_match_table = twl_gpio_match,
632 },
633 .probe = gpio_twl4030_probe,
634 .remove = gpio_twl4030_remove,
635};
636
637static int __init gpio_twl4030_init(void)
638{
639 return platform_driver_register(&gpio_twl4030_driver);
640}
641subsys_initcall(gpio_twl4030_init);
642
643static void __exit gpio_twl4030_exit(void)
644{
645 platform_driver_unregister(&gpio_twl4030_driver);
646}
647module_exit(gpio_twl4030_exit);
648
649MODULE_AUTHOR("Texas Instruments, Inc.");
650MODULE_DESCRIPTION("GPIO interface for TWL4030");
651MODULE_LICENSE("GPL");
652