1/*
2 * gpiolib support for Wolfson WM8994
3 *
4 * Copyright 2009 Wolfson Microelectronics PLC.
5 *
6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
7 *
8 *  This program is free software; you can redistribute  it and/or modify it
9 *  under  the terms of  the GNU General  Public License as published by the
10 *  Free Software Foundation;  either version 2 of the  License, or (at your
11 *  option) any later version.
12 *
13 */
14
15#include <linux/kernel.h>
16#include <linux/slab.h>
17#include <linux/module.h>
18#include <linux/gpio.h>
19#include <linux/mfd/core.h>
20#include <linux/platform_device.h>
21#include <linux/seq_file.h>
22#include <linux/regmap.h>
23
24#include <linux/mfd/wm8994/core.h>
25#include <linux/mfd/wm8994/pdata.h>
26#include <linux/mfd/wm8994/gpio.h>
27#include <linux/mfd/wm8994/registers.h>
28
29struct wm8994_gpio {
30	struct wm8994 *wm8994;
31	struct gpio_chip gpio_chip;
32};
33
34static inline struct wm8994_gpio *to_wm8994_gpio(struct gpio_chip *chip)
35{
36	return container_of(chip, struct wm8994_gpio, gpio_chip);
37}
38
39static int wm8994_gpio_request(struct gpio_chip *chip, unsigned offset)
40{
41	struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
42	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
43
44	switch (wm8994->type) {
45	case WM8958:
46		switch (offset) {
47		case 1:
48		case 2:
49		case 3:
50		case 4:
51		case 6:
52			return -EINVAL;
53		}
54		break;
55	default:
56		break;
57	}
58
59	return 0;
60}
61
62static int wm8994_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
63{
64	struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
65	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
66
67	return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
68			       WM8994_GPN_DIR, WM8994_GPN_DIR);
69}
70
71static int wm8994_gpio_get(struct gpio_chip *chip, unsigned offset)
72{
73	struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
74	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
75	int ret;
76
77	ret = wm8994_reg_read(wm8994, WM8994_GPIO_1 + offset);
78	if (ret < 0)
79		return ret;
80
81	if (ret & WM8994_GPN_LVL)
82		return 1;
83	else
84		return 0;
85}
86
87static int wm8994_gpio_direction_out(struct gpio_chip *chip,
88				     unsigned offset, int value)
89{
90	struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
91	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
92
93	if (value)
94		value = WM8994_GPN_LVL;
95
96	return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
97			       WM8994_GPN_DIR | WM8994_GPN_LVL, value);
98}
99
100static void wm8994_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
101{
102	struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
103	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
104
105	if (value)
106		value = WM8994_GPN_LVL;
107
108	wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, WM8994_GPN_LVL, value);
109}
110
111static int wm8994_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
112{
113	struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
114	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
115
116	return regmap_irq_get_virq(wm8994->irq_data, offset);
117}
118
119
120#ifdef CONFIG_DEBUG_FS
121static const char *wm8994_gpio_fn(u16 fn)
122{
123	switch (fn) {
124	case WM8994_GP_FN_PIN_SPECIFIC:
125		return "pin-specific";
126	case WM8994_GP_FN_GPIO:
127		return "GPIO";
128	case WM8994_GP_FN_SDOUT:
129		return "SDOUT";
130	case WM8994_GP_FN_IRQ:
131		return "IRQ";
132	case WM8994_GP_FN_TEMPERATURE:
133		return "Temperature";
134	case WM8994_GP_FN_MICBIAS1_DET:
135		return "MICBIAS1 detect";
136	case WM8994_GP_FN_MICBIAS1_SHORT:
137		return "MICBIAS1 short";
138	case WM8994_GP_FN_MICBIAS2_DET:
139		return "MICBIAS2 detect";
140	case WM8994_GP_FN_MICBIAS2_SHORT:
141		return "MICBIAS2 short";
142	case WM8994_GP_FN_FLL1_LOCK:
143		return "FLL1 lock";
144	case WM8994_GP_FN_FLL2_LOCK:
145		return "FLL2 lock";
146	case WM8994_GP_FN_SRC1_LOCK:
147		return "SRC1 lock";
148	case WM8994_GP_FN_SRC2_LOCK:
149		return "SRC2 lock";
150	case WM8994_GP_FN_DRC1_ACT:
151		return "DRC1 activity";
152	case WM8994_GP_FN_DRC2_ACT:
153		return "DRC2 activity";
154	case WM8994_GP_FN_DRC3_ACT:
155		return "DRC3 activity";
156	case WM8994_GP_FN_WSEQ_STATUS:
157		return "Write sequencer";
158	case WM8994_GP_FN_FIFO_ERROR:
159		return "FIFO error";
160	case WM8994_GP_FN_OPCLK:
161		return "OPCLK";
162	case WM8994_GP_FN_THW:
163		return "Thermal warning";
164	case WM8994_GP_FN_DCS_DONE:
165		return "DC servo";
166	case WM8994_GP_FN_FLL1_OUT:
167		return "FLL1 output";
168	case WM8994_GP_FN_FLL2_OUT:
169		return "FLL1 output";
170	default:
171		return "Unknown";
172	}
173}
174
175static void wm8994_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
176{
177	struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
178	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
179	int i;
180
181	for (i = 0; i < chip->ngpio; i++) {
182		int gpio = i + chip->base;
183		int reg;
184		const char *label;
185
186		/* We report the GPIO even if it's not requested since
187		 * we're also reporting things like alternate
188		 * functions which apply even when the GPIO is not in
189		 * use as a GPIO.
190		 */
191		label = gpiochip_is_requested(chip, i);
192		if (!label)
193			label = "Unrequested";
194
195		seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label);
196
197		reg = wm8994_reg_read(wm8994, WM8994_GPIO_1 + i);
198		if (reg < 0) {
199			dev_err(wm8994->dev,
200				"GPIO control %d read failed: %d\n",
201				gpio, reg);
202			seq_printf(s, "\n");
203			continue;
204		}
205
206		if (reg & WM8994_GPN_DIR)
207			seq_printf(s, "in ");
208		else
209			seq_printf(s, "out ");
210
211		if (reg & WM8994_GPN_PU)
212			seq_printf(s, "pull up ");
213
214		if (reg & WM8994_GPN_PD)
215			seq_printf(s, "pull down ");
216
217		if (reg & WM8994_GPN_POL)
218			seq_printf(s, "inverted ");
219		else
220			seq_printf(s, "noninverted ");
221
222		if (reg & WM8994_GPN_OP_CFG)
223			seq_printf(s, "open drain ");
224		else
225			seq_printf(s, "CMOS ");
226
227		seq_printf(s, "%s (%x)\n",
228			   wm8994_gpio_fn(reg & WM8994_GPN_FN_MASK), reg);
229	}
230}
231#else
232#define wm8994_gpio_dbg_show NULL
233#endif
234
235static struct gpio_chip template_chip = {
236	.label			= "wm8994",
237	.owner			= THIS_MODULE,
238	.request		= wm8994_gpio_request,
239	.direction_input	= wm8994_gpio_direction_in,
240	.get			= wm8994_gpio_get,
241	.direction_output	= wm8994_gpio_direction_out,
242	.set			= wm8994_gpio_set,
243	.to_irq			= wm8994_gpio_to_irq,
244	.dbg_show		= wm8994_gpio_dbg_show,
245	.can_sleep		= true,
246};
247
248static int wm8994_gpio_probe(struct platform_device *pdev)
249{
250	struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent);
251	struct wm8994_pdata *pdata = dev_get_platdata(wm8994->dev);
252	struct wm8994_gpio *wm8994_gpio;
253	int ret;
254
255	wm8994_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8994_gpio),
256				   GFP_KERNEL);
257	if (wm8994_gpio == NULL)
258		return -ENOMEM;
259
260	wm8994_gpio->wm8994 = wm8994;
261	wm8994_gpio->gpio_chip = template_chip;
262	wm8994_gpio->gpio_chip.ngpio = WM8994_GPIO_MAX;
263	wm8994_gpio->gpio_chip.dev = &pdev->dev;
264	if (pdata && pdata->gpio_base)
265		wm8994_gpio->gpio_chip.base = pdata->gpio_base;
266	else
267		wm8994_gpio->gpio_chip.base = -1;
268
269	ret = gpiochip_add(&wm8994_gpio->gpio_chip);
270	if (ret < 0) {
271		dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
272			ret);
273		goto err;
274	}
275
276	platform_set_drvdata(pdev, wm8994_gpio);
277
278	return ret;
279
280err:
281	return ret;
282}
283
284static int wm8994_gpio_remove(struct platform_device *pdev)
285{
286	struct wm8994_gpio *wm8994_gpio = platform_get_drvdata(pdev);
287
288	gpiochip_remove(&wm8994_gpio->gpio_chip);
289	return 0;
290}
291
292static struct platform_driver wm8994_gpio_driver = {
293	.driver.name	= "wm8994-gpio",
294	.driver.owner	= THIS_MODULE,
295	.probe		= wm8994_gpio_probe,
296	.remove		= wm8994_gpio_remove,
297};
298
299static int __init wm8994_gpio_init(void)
300{
301	return platform_driver_register(&wm8994_gpio_driver);
302}
303subsys_initcall(wm8994_gpio_init);
304
305static void __exit wm8994_gpio_exit(void)
306{
307	platform_driver_unregister(&wm8994_gpio_driver);
308}
309module_exit(wm8994_gpio_exit);
310
311MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
312MODULE_DESCRIPTION("GPIO interface for WM8994");
313MODULE_LICENSE("GPL");
314MODULE_ALIAS("platform:wm8994-gpio");
315