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
55struct 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 */
71static 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 */
106static 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
117static 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 */
123static 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
139static 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
159static 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
176static 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
190static 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
207static 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
267done:
268	if (!status)
269		priv->usage_count |= BIT(offset);
270
271	mutex_unlock(&priv->mutex);
272	return status;
273}
274
275static 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
291out:
292	mutex_unlock(&priv->mutex);
293}
294
295static 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
314static 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;
332out:
333	mutex_unlock(&priv->mutex);
334	return ret;
335}
336
337static 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
355static 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
381static 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
403static 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
412static 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
428static 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
453static 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
470static 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 */
494static 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
502static 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
536no_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
608static const struct of_device_id twl_gpio_match[] = {
609	{ .compatible = "ti,twl4030-gpio", },
610	{ },
611};
612MODULE_DEVICE_TABLE(of, twl_gpio_match);
613
614/* Note:  this hardware lives inside an I2C-based multi-function device. */
615MODULE_ALIAS("platform:twl4030_gpio");
616
617static 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
625static int __init gpio_twl4030_init(void)
626{
627	return platform_driver_register(&gpio_twl4030_driver);
628}
629subsys_initcall(gpio_twl4030_init);
630
631static void __exit gpio_twl4030_exit(void)
632{
633	platform_driver_unregister(&gpio_twl4030_driver);
634}
635module_exit(gpio_twl4030_exit);
636
637MODULE_AUTHOR("Texas Instruments, Inc.");
638MODULE_DESCRIPTION("GPIO interface for TWL4030");
639MODULE_LICENSE("GPL");
640