xref: /linux/drivers/gpio/gpio-wm831x.c (revision 718bc6e33f33914690ba1b757de2327da7522a87)
1e4b736f1SMark Brown /*
2c103de24SGrant Likely  * gpiolib support for Wolfson WM831x PMICs
3e4b736f1SMark Brown  *
4e4b736f1SMark Brown  * Copyright 2009 Wolfson Microelectronics PLC.
5e4b736f1SMark Brown  *
6e4b736f1SMark Brown  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
7e4b736f1SMark Brown  *
8e4b736f1SMark Brown  *  This program is free software; you can redistribute  it and/or modify it
9e4b736f1SMark Brown  *  under  the terms of  the GNU General  Public License as published by the
10e4b736f1SMark Brown  *  Free Software Foundation;  either version 2 of the  License, or (at your
11e4b736f1SMark Brown  *  option) any later version.
12e4b736f1SMark Brown  *
13e4b736f1SMark Brown  */
14e4b736f1SMark Brown 
15e4b736f1SMark Brown #include <linux/kernel.h>
165a0e3ad6STejun Heo #include <linux/slab.h>
17e4b736f1SMark Brown #include <linux/module.h>
18e4b736f1SMark Brown #include <linux/gpio.h>
19e4b736f1SMark Brown #include <linux/mfd/core.h>
20e4b736f1SMark Brown #include <linux/platform_device.h>
21e4b736f1SMark Brown #include <linux/seq_file.h>
22e4b736f1SMark Brown 
23e4b736f1SMark Brown #include <linux/mfd/wm831x/core.h>
24e4b736f1SMark Brown #include <linux/mfd/wm831x/pdata.h>
25e4b736f1SMark Brown #include <linux/mfd/wm831x/gpio.h>
26dc0fb25cSMark Brown #include <linux/mfd/wm831x/irq.h>
27e4b736f1SMark Brown 
28e4b736f1SMark Brown struct wm831x_gpio {
29e4b736f1SMark Brown 	struct wm831x *wm831x;
30e4b736f1SMark Brown 	struct gpio_chip gpio_chip;
31e4b736f1SMark Brown };
32e4b736f1SMark Brown 
33e4b736f1SMark Brown static inline struct wm831x_gpio *to_wm831x_gpio(struct gpio_chip *chip)
34e4b736f1SMark Brown {
35e4b736f1SMark Brown 	return container_of(chip, struct wm831x_gpio, gpio_chip);
36e4b736f1SMark Brown }
37e4b736f1SMark Brown 
38e4b736f1SMark Brown static int wm831x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
39e4b736f1SMark Brown {
40e4b736f1SMark Brown 	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
41e4b736f1SMark Brown 	struct wm831x *wm831x = wm831x_gpio->wm831x;
42f92e8f81SMark Brown 	int val = WM831X_GPN_DIR;
43f92e8f81SMark Brown 
44f92e8f81SMark Brown 	if (wm831x->has_gpio_ena)
45f92e8f81SMark Brown 		val |= WM831X_GPN_TRI;
46e4b736f1SMark Brown 
47e4b736f1SMark Brown 	return wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset,
481bca748cSMark Brown 			       WM831X_GPN_DIR | WM831X_GPN_TRI |
491bca748cSMark Brown 			       WM831X_GPN_FN_MASK, val);
50e4b736f1SMark Brown }
51e4b736f1SMark Brown 
52e4b736f1SMark Brown static int wm831x_gpio_get(struct gpio_chip *chip, unsigned offset)
53e4b736f1SMark Brown {
54e4b736f1SMark Brown 	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
55e4b736f1SMark Brown 	struct wm831x *wm831x = wm831x_gpio->wm831x;
56e4b736f1SMark Brown 	int ret;
57e4b736f1SMark Brown 
58e4b736f1SMark Brown 	ret = wm831x_reg_read(wm831x, WM831X_GPIO_LEVEL);
59e4b736f1SMark Brown 	if (ret < 0)
60e4b736f1SMark Brown 		return ret;
61e4b736f1SMark Brown 
62e4b736f1SMark Brown 	if (ret & 1 << offset)
63e4b736f1SMark Brown 		return 1;
64e4b736f1SMark Brown 	else
65e4b736f1SMark Brown 		return 0;
66e4b736f1SMark Brown }
67e4b736f1SMark Brown 
68e4b736f1SMark Brown static void wm831x_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
69e4b736f1SMark Brown {
70e4b736f1SMark Brown 	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
71e4b736f1SMark Brown 	struct wm831x *wm831x = wm831x_gpio->wm831x;
72e4b736f1SMark Brown 
73e4b736f1SMark Brown 	wm831x_set_bits(wm831x, WM831X_GPIO_LEVEL, 1 << offset,
74e4b736f1SMark Brown 			value << offset);
75e4b736f1SMark Brown }
76e4b736f1SMark Brown 
773383d23dSMark Brown static int wm831x_gpio_direction_out(struct gpio_chip *chip,
783383d23dSMark Brown 				     unsigned offset, int value)
793383d23dSMark Brown {
803383d23dSMark Brown 	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
813383d23dSMark Brown 	struct wm831x *wm831x = wm831x_gpio->wm831x;
82f92e8f81SMark Brown 	int val = 0;
833383d23dSMark Brown 	int ret;
843383d23dSMark Brown 
85f92e8f81SMark Brown 	if (wm831x->has_gpio_ena)
86f92e8f81SMark Brown 		val |= WM831X_GPN_TRI;
87f92e8f81SMark Brown 
883383d23dSMark Brown 	ret = wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset,
891bca748cSMark Brown 			      WM831X_GPN_DIR | WM831X_GPN_TRI |
901bca748cSMark Brown 			      WM831X_GPN_FN_MASK, val);
913383d23dSMark Brown 	if (ret < 0)
923383d23dSMark Brown 		return ret;
933383d23dSMark Brown 
943383d23dSMark Brown 	/* Can only set GPIO state once it's in output mode */
953383d23dSMark Brown 	wm831x_gpio_set(chip, offset, value);
963383d23dSMark Brown 
973383d23dSMark Brown 	return 0;
983383d23dSMark Brown }
993383d23dSMark Brown 
100dc0fb25cSMark Brown static int wm831x_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
101dc0fb25cSMark Brown {
102dc0fb25cSMark Brown 	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
103dc0fb25cSMark Brown 	struct wm831x *wm831x = wm831x_gpio->wm831x;
104dc0fb25cSMark Brown 
105cd99758bSMark Brown 	return irq_create_mapping(wm831x->irq_domain,
106cd99758bSMark Brown 				  WM831X_IRQ_GPIO_1 + offset);
107dc0fb25cSMark Brown }
108dc0fb25cSMark Brown 
109b12c35e2SMark Brown static int wm831x_gpio_set_debounce(struct gpio_chip *chip, unsigned offset,
110b12c35e2SMark Brown 				    unsigned debounce)
111b12c35e2SMark Brown {
112b12c35e2SMark Brown 	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
113b12c35e2SMark Brown 	struct wm831x *wm831x = wm831x_gpio->wm831x;
114b12c35e2SMark Brown 	int reg = WM831X_GPIO1_CONTROL + offset;
115b12c35e2SMark Brown 	int ret, fn;
116b12c35e2SMark Brown 
117b12c35e2SMark Brown 	ret = wm831x_reg_read(wm831x, reg);
118b12c35e2SMark Brown 	if (ret < 0)
119b12c35e2SMark Brown 		return ret;
120b12c35e2SMark Brown 
121b12c35e2SMark Brown 	switch (ret & WM831X_GPN_FN_MASK) {
122b12c35e2SMark Brown 	case 0:
123b12c35e2SMark Brown 	case 1:
124b12c35e2SMark Brown 		break;
125b12c35e2SMark Brown 	default:
126b12c35e2SMark Brown 		/* Not in GPIO mode */
127b12c35e2SMark Brown 		return -EBUSY;
128b12c35e2SMark Brown 	}
129b12c35e2SMark Brown 
130b12c35e2SMark Brown 	if (debounce >= 32 && debounce <= 64)
131b12c35e2SMark Brown 		fn = 0;
132b12c35e2SMark Brown 	else if (debounce >= 4000 && debounce <= 8000)
133b12c35e2SMark Brown 		fn = 1;
134b12c35e2SMark Brown 	else
135b12c35e2SMark Brown 		return -EINVAL;
136b12c35e2SMark Brown 
137b12c35e2SMark Brown 	return wm831x_set_bits(wm831x, reg, WM831X_GPN_FN_MASK, fn);
138b12c35e2SMark Brown }
139b12c35e2SMark Brown 
140e4b736f1SMark Brown #ifdef CONFIG_DEBUG_FS
141e4b736f1SMark Brown static void wm831x_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
142e4b736f1SMark Brown {
143e4b736f1SMark Brown 	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
144e4b736f1SMark Brown 	struct wm831x *wm831x = wm831x_gpio->wm831x;
145f92e8f81SMark Brown 	int i, tristated;
146e4b736f1SMark Brown 
147e4b736f1SMark Brown 	for (i = 0; i < chip->ngpio; i++) {
148e4b736f1SMark Brown 		int gpio = i + chip->base;
149e4b736f1SMark Brown 		int reg;
150e4b736f1SMark Brown 		const char *label, *pull, *powerdomain;
151e4b736f1SMark Brown 
152e4b736f1SMark Brown 		/* We report the GPIO even if it's not requested since
153e4b736f1SMark Brown 		 * we're also reporting things like alternate
154e4b736f1SMark Brown 		 * functions which apply even when the GPIO is not in
155e4b736f1SMark Brown 		 * use as a GPIO.
156e4b736f1SMark Brown 		 */
157e4b736f1SMark Brown 		label = gpiochip_is_requested(chip, i);
158e4b736f1SMark Brown 		if (!label)
159e4b736f1SMark Brown 			label = "Unrequested";
160e4b736f1SMark Brown 
161e4b736f1SMark Brown 		seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label);
162e4b736f1SMark Brown 
163e4b736f1SMark Brown 		reg = wm831x_reg_read(wm831x, WM831X_GPIO1_CONTROL + i);
164e4b736f1SMark Brown 		if (reg < 0) {
165e4b736f1SMark Brown 			dev_err(wm831x->dev,
166e4b736f1SMark Brown 				"GPIO control %d read failed: %d\n",
167e4b736f1SMark Brown 				gpio, reg);
168e4b736f1SMark Brown 			seq_printf(s, "\n");
169e4b736f1SMark Brown 			continue;
170e4b736f1SMark Brown 		}
171e4b736f1SMark Brown 
172e4b736f1SMark Brown 		switch (reg & WM831X_GPN_PULL_MASK) {
173e4b736f1SMark Brown 		case WM831X_GPIO_PULL_NONE:
174e4b736f1SMark Brown 			pull = "nopull";
175e4b736f1SMark Brown 			break;
176e4b736f1SMark Brown 		case WM831X_GPIO_PULL_DOWN:
177e4b736f1SMark Brown 			pull = "pulldown";
178e4b736f1SMark Brown 			break;
179e4b736f1SMark Brown 		case WM831X_GPIO_PULL_UP:
180e4b736f1SMark Brown 			pull = "pullup";
181164d5c39SAxel Lin 			break;
182e4b736f1SMark Brown 		default:
183e4b736f1SMark Brown 			pull = "INVALID PULL";
184e4b736f1SMark Brown 			break;
185e4b736f1SMark Brown 		}
186e4b736f1SMark Brown 
187e4b736f1SMark Brown 		switch (i + 1) {
188e4b736f1SMark Brown 		case 1 ... 3:
189e4b736f1SMark Brown 		case 7 ... 9:
190e4b736f1SMark Brown 			if (reg & WM831X_GPN_PWR_DOM)
191e4b736f1SMark Brown 				powerdomain = "VPMIC";
192e4b736f1SMark Brown 			else
193e4b736f1SMark Brown 				powerdomain = "DBVDD";
194e4b736f1SMark Brown 			break;
195e4b736f1SMark Brown 
196e4b736f1SMark Brown 		case 4 ... 6:
197e4b736f1SMark Brown 		case 10 ... 12:
198e4b736f1SMark Brown 			if (reg & WM831X_GPN_PWR_DOM)
199e4b736f1SMark Brown 				powerdomain = "SYSVDD";
200e4b736f1SMark Brown 			else
201e4b736f1SMark Brown 				powerdomain = "DBVDD";
202e4b736f1SMark Brown 			break;
203e4b736f1SMark Brown 
204e4b736f1SMark Brown 		case 13 ... 16:
205e4b736f1SMark Brown 			powerdomain = "TPVDD";
206e4b736f1SMark Brown 			break;
207e4b736f1SMark Brown 
208e4b736f1SMark Brown 		default:
209e4b736f1SMark Brown 			BUG();
210e4b736f1SMark Brown 			break;
211e4b736f1SMark Brown 		}
212e4b736f1SMark Brown 
213f92e8f81SMark Brown 		tristated = reg & WM831X_GPN_TRI;
214f92e8f81SMark Brown 		if (wm831x->has_gpio_ena)
215f92e8f81SMark Brown 			tristated = !tristated;
216f92e8f81SMark Brown 
217e4b736f1SMark Brown 		seq_printf(s, " %s %s %s %s%s\n"
218e4b736f1SMark Brown 			   "                                  %s%s (0x%4x)\n",
219e4b736f1SMark Brown 			   reg & WM831X_GPN_DIR ? "in" : "out",
220e4b736f1SMark Brown 			   wm831x_gpio_get(chip, i) ? "high" : "low",
221e4b736f1SMark Brown 			   pull,
222e4b736f1SMark Brown 			   powerdomain,
2236b8274faSMark Brown 			   reg & WM831X_GPN_POL ? "" : " inverted",
224e4b736f1SMark Brown 			   reg & WM831X_GPN_OD ? "open-drain" : "CMOS",
225f92e8f81SMark Brown 			   tristated ? " tristated" : "",
226e4b736f1SMark Brown 			   reg);
227e4b736f1SMark Brown 	}
228e4b736f1SMark Brown }
229e4b736f1SMark Brown #else
230e4b736f1SMark Brown #define wm831x_gpio_dbg_show NULL
231e4b736f1SMark Brown #endif
232e4b736f1SMark Brown 
233e4b736f1SMark Brown static struct gpio_chip template_chip = {
234e4b736f1SMark Brown 	.label			= "wm831x",
235e4b736f1SMark Brown 	.owner			= THIS_MODULE,
236e4b736f1SMark Brown 	.direction_input	= wm831x_gpio_direction_in,
237e4b736f1SMark Brown 	.get			= wm831x_gpio_get,
238e4b736f1SMark Brown 	.direction_output	= wm831x_gpio_direction_out,
239e4b736f1SMark Brown 	.set			= wm831x_gpio_set,
240dc0fb25cSMark Brown 	.to_irq			= wm831x_gpio_to_irq,
241b12c35e2SMark Brown 	.set_debounce		= wm831x_gpio_set_debounce,
242e4b736f1SMark Brown 	.dbg_show		= wm831x_gpio_dbg_show,
243e4b736f1SMark Brown 	.can_sleep		= 1,
244e4b736f1SMark Brown };
245e4b736f1SMark Brown 
246e4b736f1SMark Brown static int __devinit wm831x_gpio_probe(struct platform_device *pdev)
247e4b736f1SMark Brown {
248e4b736f1SMark Brown 	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
249e4b736f1SMark Brown 	struct wm831x_pdata *pdata = wm831x->dev->platform_data;
250e4b736f1SMark Brown 	struct wm831x_gpio *wm831x_gpio;
251e4b736f1SMark Brown 	int ret;
252e4b736f1SMark Brown 
253*718bc6e3SAxel Lin 	wm831x_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm831x_gpio),
254*718bc6e3SAxel Lin 				   GFP_KERNEL);
255e4b736f1SMark Brown 	if (wm831x_gpio == NULL)
256e4b736f1SMark Brown 		return -ENOMEM;
257e4b736f1SMark Brown 
258e4b736f1SMark Brown 	wm831x_gpio->wm831x = wm831x;
259e4b736f1SMark Brown 	wm831x_gpio->gpio_chip = template_chip;
2606f2ecaaeSMark Brown 	wm831x_gpio->gpio_chip.ngpio = wm831x->num_gpio;
261e4b736f1SMark Brown 	wm831x_gpio->gpio_chip.dev = &pdev->dev;
262e4b736f1SMark Brown 	if (pdata && pdata->gpio_base)
263e4b736f1SMark Brown 		wm831x_gpio->gpio_chip.base = pdata->gpio_base;
264e4b736f1SMark Brown 	else
265e4b736f1SMark Brown 		wm831x_gpio->gpio_chip.base = -1;
266e4b736f1SMark Brown 
267e4b736f1SMark Brown 	ret = gpiochip_add(&wm831x_gpio->gpio_chip);
268e4b736f1SMark Brown 	if (ret < 0) {
269*718bc6e3SAxel Lin 		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
270*718bc6e3SAxel Lin 		return ret;
271e4b736f1SMark Brown 	}
272e4b736f1SMark Brown 
273e4b736f1SMark Brown 	platform_set_drvdata(pdev, wm831x_gpio);
274e4b736f1SMark Brown 
275e4b736f1SMark Brown 	return ret;
276e4b736f1SMark Brown }
277e4b736f1SMark Brown 
278e4b736f1SMark Brown static int __devexit wm831x_gpio_remove(struct platform_device *pdev)
279e4b736f1SMark Brown {
280e4b736f1SMark Brown 	struct wm831x_gpio *wm831x_gpio = platform_get_drvdata(pdev);
281e4b736f1SMark Brown 
282*718bc6e3SAxel Lin 	return  gpiochip_remove(&wm831x_gpio->gpio_chip);
283e4b736f1SMark Brown }
284e4b736f1SMark Brown 
285e4b736f1SMark Brown static struct platform_driver wm831x_gpio_driver = {
286e4b736f1SMark Brown 	.driver.name	= "wm831x-gpio",
287e4b736f1SMark Brown 	.driver.owner	= THIS_MODULE,
288e4b736f1SMark Brown 	.probe		= wm831x_gpio_probe,
289e4b736f1SMark Brown 	.remove		= __devexit_p(wm831x_gpio_remove),
290e4b736f1SMark Brown };
291e4b736f1SMark Brown 
292e4b736f1SMark Brown static int __init wm831x_gpio_init(void)
293e4b736f1SMark Brown {
294e4b736f1SMark Brown 	return platform_driver_register(&wm831x_gpio_driver);
295e4b736f1SMark Brown }
296e4b736f1SMark Brown subsys_initcall(wm831x_gpio_init);
297e4b736f1SMark Brown 
298e4b736f1SMark Brown static void __exit wm831x_gpio_exit(void)
299e4b736f1SMark Brown {
300e4b736f1SMark Brown 	platform_driver_unregister(&wm831x_gpio_driver);
301e4b736f1SMark Brown }
302e4b736f1SMark Brown module_exit(wm831x_gpio_exit);
303e4b736f1SMark Brown 
304e4b736f1SMark Brown MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
305e4b736f1SMark Brown MODULE_DESCRIPTION("GPIO interface for WM831x PMICs");
306e4b736f1SMark Brown MODULE_LICENSE("GPL");
307e4b736f1SMark Brown MODULE_ALIAS("platform:wm831x-gpio");
308