xref: /openbmc/linux/drivers/gpio/gpio-wm8994.c (revision 32981ea5)
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 
29 struct wm8994_gpio {
30 	struct wm8994 *wm8994;
31 	struct gpio_chip gpio_chip;
32 };
33 
34 static int wm8994_gpio_request(struct gpio_chip *chip, unsigned offset)
35 {
36 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
37 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
38 
39 	switch (wm8994->type) {
40 	case WM8958:
41 		switch (offset) {
42 		case 1:
43 		case 2:
44 		case 3:
45 		case 4:
46 		case 6:
47 			return -EINVAL;
48 		}
49 		break;
50 	default:
51 		break;
52 	}
53 
54 	return 0;
55 }
56 
57 static int wm8994_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
58 {
59 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
60 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
61 
62 	return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
63 			       WM8994_GPN_DIR, WM8994_GPN_DIR);
64 }
65 
66 static int wm8994_gpio_get(struct gpio_chip *chip, unsigned offset)
67 {
68 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
69 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
70 	int ret;
71 
72 	ret = wm8994_reg_read(wm8994, WM8994_GPIO_1 + offset);
73 	if (ret < 0)
74 		return ret;
75 
76 	if (ret & WM8994_GPN_LVL)
77 		return 1;
78 	else
79 		return 0;
80 }
81 
82 static int wm8994_gpio_direction_out(struct gpio_chip *chip,
83 				     unsigned offset, int value)
84 {
85 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
86 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
87 
88 	if (value)
89 		value = WM8994_GPN_LVL;
90 
91 	return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
92 			       WM8994_GPN_DIR | WM8994_GPN_LVL, value);
93 }
94 
95 static void wm8994_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
96 {
97 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
98 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
99 
100 	if (value)
101 		value = WM8994_GPN_LVL;
102 
103 	wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, WM8994_GPN_LVL, value);
104 }
105 
106 static int wm8994_gpio_set_single_ended(struct gpio_chip *chip,
107 					unsigned int offset,
108 					enum single_ended_mode mode)
109 {
110 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
111 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
112 
113 	switch (mode) {
114 	case LINE_MODE_OPEN_DRAIN:
115 		return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
116 				       WM8994_GPN_OP_CFG_MASK,
117 				       WM8994_GPN_OP_CFG);
118 	case LINE_MODE_PUSH_PULL:
119 		return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
120 				       WM8994_GPN_OP_CFG_MASK, 0);
121 	default:
122 		break;
123 	}
124 
125 	return -ENOTSUPP;
126 }
127 
128 static int wm8994_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
129 {
130 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
131 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
132 
133 	return regmap_irq_get_virq(wm8994->irq_data, offset);
134 }
135 
136 
137 #ifdef CONFIG_DEBUG_FS
138 static const char *wm8994_gpio_fn(u16 fn)
139 {
140 	switch (fn) {
141 	case WM8994_GP_FN_PIN_SPECIFIC:
142 		return "pin-specific";
143 	case WM8994_GP_FN_GPIO:
144 		return "GPIO";
145 	case WM8994_GP_FN_SDOUT:
146 		return "SDOUT";
147 	case WM8994_GP_FN_IRQ:
148 		return "IRQ";
149 	case WM8994_GP_FN_TEMPERATURE:
150 		return "Temperature";
151 	case WM8994_GP_FN_MICBIAS1_DET:
152 		return "MICBIAS1 detect";
153 	case WM8994_GP_FN_MICBIAS1_SHORT:
154 		return "MICBIAS1 short";
155 	case WM8994_GP_FN_MICBIAS2_DET:
156 		return "MICBIAS2 detect";
157 	case WM8994_GP_FN_MICBIAS2_SHORT:
158 		return "MICBIAS2 short";
159 	case WM8994_GP_FN_FLL1_LOCK:
160 		return "FLL1 lock";
161 	case WM8994_GP_FN_FLL2_LOCK:
162 		return "FLL2 lock";
163 	case WM8994_GP_FN_SRC1_LOCK:
164 		return "SRC1 lock";
165 	case WM8994_GP_FN_SRC2_LOCK:
166 		return "SRC2 lock";
167 	case WM8994_GP_FN_DRC1_ACT:
168 		return "DRC1 activity";
169 	case WM8994_GP_FN_DRC2_ACT:
170 		return "DRC2 activity";
171 	case WM8994_GP_FN_DRC3_ACT:
172 		return "DRC3 activity";
173 	case WM8994_GP_FN_WSEQ_STATUS:
174 		return "Write sequencer";
175 	case WM8994_GP_FN_FIFO_ERROR:
176 		return "FIFO error";
177 	case WM8994_GP_FN_OPCLK:
178 		return "OPCLK";
179 	case WM8994_GP_FN_THW:
180 		return "Thermal warning";
181 	case WM8994_GP_FN_DCS_DONE:
182 		return "DC servo";
183 	case WM8994_GP_FN_FLL1_OUT:
184 		return "FLL1 output";
185 	case WM8994_GP_FN_FLL2_OUT:
186 		return "FLL1 output";
187 	default:
188 		return "Unknown";
189 	}
190 }
191 
192 static void wm8994_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
193 {
194 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
195 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
196 	int i;
197 
198 	for (i = 0; i < chip->ngpio; i++) {
199 		int gpio = i + chip->base;
200 		int reg;
201 		const char *label;
202 
203 		/* We report the GPIO even if it's not requested since
204 		 * we're also reporting things like alternate
205 		 * functions which apply even when the GPIO is not in
206 		 * use as a GPIO.
207 		 */
208 		label = gpiochip_is_requested(chip, i);
209 		if (!label)
210 			label = "Unrequested";
211 
212 		seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label);
213 
214 		reg = wm8994_reg_read(wm8994, WM8994_GPIO_1 + i);
215 		if (reg < 0) {
216 			dev_err(wm8994->dev,
217 				"GPIO control %d read failed: %d\n",
218 				gpio, reg);
219 			seq_printf(s, "\n");
220 			continue;
221 		}
222 
223 		if (reg & WM8994_GPN_DIR)
224 			seq_printf(s, "in ");
225 		else
226 			seq_printf(s, "out ");
227 
228 		if (reg & WM8994_GPN_PU)
229 			seq_printf(s, "pull up ");
230 
231 		if (reg & WM8994_GPN_PD)
232 			seq_printf(s, "pull down ");
233 
234 		if (reg & WM8994_GPN_POL)
235 			seq_printf(s, "inverted ");
236 		else
237 			seq_printf(s, "noninverted ");
238 
239 		if (reg & WM8994_GPN_OP_CFG)
240 			seq_printf(s, "open drain ");
241 		else
242 			seq_printf(s, "push-pull ");
243 
244 		seq_printf(s, "%s (%x)\n",
245 			   wm8994_gpio_fn(reg & WM8994_GPN_FN_MASK), reg);
246 	}
247 }
248 #else
249 #define wm8994_gpio_dbg_show NULL
250 #endif
251 
252 static struct gpio_chip template_chip = {
253 	.label			= "wm8994",
254 	.owner			= THIS_MODULE,
255 	.request		= wm8994_gpio_request,
256 	.direction_input	= wm8994_gpio_direction_in,
257 	.get			= wm8994_gpio_get,
258 	.direction_output	= wm8994_gpio_direction_out,
259 	.set			= wm8994_gpio_set,
260 	.set_single_ended	= wm8994_gpio_set_single_ended,
261 	.to_irq			= wm8994_gpio_to_irq,
262 	.dbg_show		= wm8994_gpio_dbg_show,
263 	.can_sleep		= true,
264 };
265 
266 static int wm8994_gpio_probe(struct platform_device *pdev)
267 {
268 	struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent);
269 	struct wm8994_pdata *pdata = dev_get_platdata(wm8994->dev);
270 	struct wm8994_gpio *wm8994_gpio;
271 	int ret;
272 
273 	wm8994_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8994_gpio),
274 				   GFP_KERNEL);
275 	if (wm8994_gpio == NULL)
276 		return -ENOMEM;
277 
278 	wm8994_gpio->wm8994 = wm8994;
279 	wm8994_gpio->gpio_chip = template_chip;
280 	wm8994_gpio->gpio_chip.ngpio = WM8994_GPIO_MAX;
281 	wm8994_gpio->gpio_chip.parent = &pdev->dev;
282 	if (pdata && pdata->gpio_base)
283 		wm8994_gpio->gpio_chip.base = pdata->gpio_base;
284 	else
285 		wm8994_gpio->gpio_chip.base = -1;
286 
287 	ret = devm_gpiochip_add_data(&pdev->dev, &wm8994_gpio->gpio_chip,
288 				     wm8994_gpio);
289 	if (ret < 0) {
290 		dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
291 			ret);
292 		return ret;
293 	}
294 
295 	platform_set_drvdata(pdev, wm8994_gpio);
296 
297 	return ret;
298 }
299 
300 static struct platform_driver wm8994_gpio_driver = {
301 	.driver.name	= "wm8994-gpio",
302 	.driver.owner	= THIS_MODULE,
303 	.probe		= wm8994_gpio_probe,
304 };
305 
306 static int __init wm8994_gpio_init(void)
307 {
308 	return platform_driver_register(&wm8994_gpio_driver);
309 }
310 subsys_initcall(wm8994_gpio_init);
311 
312 static void __exit wm8994_gpio_exit(void)
313 {
314 	platform_driver_unregister(&wm8994_gpio_driver);
315 }
316 module_exit(wm8994_gpio_exit);
317 
318 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
319 MODULE_DESCRIPTION("GPIO interface for WM8994");
320 MODULE_LICENSE("GPL");
321 MODULE_ALIAS("platform:wm8994-gpio");
322