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 
wm8994_gpio_request(struct gpio_chip * chip,unsigned offset)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 
wm8994_gpio_direction_in(struct gpio_chip * chip,unsigned offset)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 
wm8994_gpio_get(struct gpio_chip * chip,unsigned offset)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 
wm8994_gpio_direction_out(struct gpio_chip * chip,unsigned offset,int value)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 
wm8994_gpio_set(struct gpio_chip * chip,unsigned offset,int value)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 
wm8994_gpio_set_config(struct gpio_chip * chip,unsigned int offset,unsigned long config)106 static int wm8994_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
107 				  unsigned long config)
108 {
109 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
110 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
111 
112 	switch (pinconf_to_config_param(config)) {
113 	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
114 		return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
115 				       WM8994_GPN_OP_CFG_MASK,
116 				       WM8994_GPN_OP_CFG);
117 	case PIN_CONFIG_DRIVE_PUSH_PULL:
118 		return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
119 				       WM8994_GPN_OP_CFG_MASK, 0);
120 	default:
121 		break;
122 	}
123 
124 	return -ENOTSUPP;
125 }
126 
wm8994_gpio_to_irq(struct gpio_chip * chip,unsigned offset)127 static int wm8994_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
128 {
129 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
130 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
131 
132 	return regmap_irq_get_virq(wm8994->irq_data, offset);
133 }
134 
135 
136 #ifdef CONFIG_DEBUG_FS
wm8994_gpio_fn(u16 fn)137 static const char *wm8994_gpio_fn(u16 fn)
138 {
139 	switch (fn) {
140 	case WM8994_GP_FN_PIN_SPECIFIC:
141 		return "pin-specific";
142 	case WM8994_GP_FN_GPIO:
143 		return "GPIO";
144 	case WM8994_GP_FN_SDOUT:
145 		return "SDOUT";
146 	case WM8994_GP_FN_IRQ:
147 		return "IRQ";
148 	case WM8994_GP_FN_TEMPERATURE:
149 		return "Temperature";
150 	case WM8994_GP_FN_MICBIAS1_DET:
151 		return "MICBIAS1 detect";
152 	case WM8994_GP_FN_MICBIAS1_SHORT:
153 		return "MICBIAS1 short";
154 	case WM8994_GP_FN_MICBIAS2_DET:
155 		return "MICBIAS2 detect";
156 	case WM8994_GP_FN_MICBIAS2_SHORT:
157 		return "MICBIAS2 short";
158 	case WM8994_GP_FN_FLL1_LOCK:
159 		return "FLL1 lock";
160 	case WM8994_GP_FN_FLL2_LOCK:
161 		return "FLL2 lock";
162 	case WM8994_GP_FN_SRC1_LOCK:
163 		return "SRC1 lock";
164 	case WM8994_GP_FN_SRC2_LOCK:
165 		return "SRC2 lock";
166 	case WM8994_GP_FN_DRC1_ACT:
167 		return "DRC1 activity";
168 	case WM8994_GP_FN_DRC2_ACT:
169 		return "DRC2 activity";
170 	case WM8994_GP_FN_DRC3_ACT:
171 		return "DRC3 activity";
172 	case WM8994_GP_FN_WSEQ_STATUS:
173 		return "Write sequencer";
174 	case WM8994_GP_FN_FIFO_ERROR:
175 		return "FIFO error";
176 	case WM8994_GP_FN_OPCLK:
177 		return "OPCLK";
178 	case WM8994_GP_FN_THW:
179 		return "Thermal warning";
180 	case WM8994_GP_FN_DCS_DONE:
181 		return "DC servo";
182 	case WM8994_GP_FN_FLL1_OUT:
183 		return "FLL1 output";
184 	case WM8994_GP_FN_FLL2_OUT:
185 		return "FLL1 output";
186 	default:
187 		return "Unknown";
188 	}
189 }
190 
wm8994_gpio_dbg_show(struct seq_file * s,struct gpio_chip * chip)191 static void wm8994_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
192 {
193 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
194 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
195 	int i;
196 
197 	for (i = 0; i < chip->ngpio; i++) {
198 		int gpio = i + chip->base;
199 		int reg;
200 		const char *label;
201 
202 		/* We report the GPIO even if it's not requested since
203 		 * we're also reporting things like alternate
204 		 * functions which apply even when the GPIO is not in
205 		 * use as a GPIO.
206 		 */
207 		label = gpiochip_is_requested(chip, i);
208 		if (!label)
209 			label = "Unrequested";
210 
211 		seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label);
212 
213 		reg = wm8994_reg_read(wm8994, WM8994_GPIO_1 + i);
214 		if (reg < 0) {
215 			dev_err(wm8994->dev,
216 				"GPIO control %d read failed: %d\n",
217 				gpio, reg);
218 			seq_printf(s, "\n");
219 			continue;
220 		}
221 
222 		if (reg & WM8994_GPN_DIR)
223 			seq_printf(s, "in ");
224 		else
225 			seq_printf(s, "out ");
226 
227 		if (reg & WM8994_GPN_PU)
228 			seq_printf(s, "pull up ");
229 
230 		if (reg & WM8994_GPN_PD)
231 			seq_printf(s, "pull down ");
232 
233 		if (reg & WM8994_GPN_POL)
234 			seq_printf(s, "inverted ");
235 		else
236 			seq_printf(s, "noninverted ");
237 
238 		if (reg & WM8994_GPN_OP_CFG)
239 			seq_printf(s, "open drain ");
240 		else
241 			seq_printf(s, "push-pull ");
242 
243 		seq_printf(s, "%s (%x)\n",
244 			   wm8994_gpio_fn(reg & WM8994_GPN_FN_MASK), reg);
245 	}
246 }
247 #else
248 #define wm8994_gpio_dbg_show NULL
249 #endif
250 
251 static const struct gpio_chip template_chip = {
252 	.label			= "wm8994",
253 	.owner			= THIS_MODULE,
254 	.request		= wm8994_gpio_request,
255 	.direction_input	= wm8994_gpio_direction_in,
256 	.get			= wm8994_gpio_get,
257 	.direction_output	= wm8994_gpio_direction_out,
258 	.set			= wm8994_gpio_set,
259 	.set_config		= wm8994_gpio_set_config,
260 	.to_irq			= wm8994_gpio_to_irq,
261 	.dbg_show		= wm8994_gpio_dbg_show,
262 	.can_sleep		= true,
263 };
264 
wm8994_gpio_probe(struct platform_device * pdev)265 static int wm8994_gpio_probe(struct platform_device *pdev)
266 {
267 	struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent);
268 	struct wm8994_pdata *pdata = dev_get_platdata(wm8994->dev);
269 	struct wm8994_gpio *wm8994_gpio;
270 	int ret;
271 
272 	wm8994_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8994_gpio),
273 				   GFP_KERNEL);
274 	if (wm8994_gpio == NULL)
275 		return -ENOMEM;
276 
277 	wm8994_gpio->wm8994 = wm8994;
278 	wm8994_gpio->gpio_chip = template_chip;
279 	wm8994_gpio->gpio_chip.ngpio = WM8994_GPIO_MAX;
280 	wm8994_gpio->gpio_chip.parent = &pdev->dev;
281 	if (pdata && pdata->gpio_base)
282 		wm8994_gpio->gpio_chip.base = pdata->gpio_base;
283 	else
284 		wm8994_gpio->gpio_chip.base = -1;
285 
286 	ret = devm_gpiochip_add_data(&pdev->dev, &wm8994_gpio->gpio_chip,
287 				     wm8994_gpio);
288 	if (ret < 0) {
289 		dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
290 			ret);
291 		return ret;
292 	}
293 
294 	platform_set_drvdata(pdev, wm8994_gpio);
295 
296 	return ret;
297 }
298 
299 static struct platform_driver wm8994_gpio_driver = {
300 	.driver.name	= "wm8994-gpio",
301 	.probe		= wm8994_gpio_probe,
302 };
303 
wm8994_gpio_init(void)304 static int __init wm8994_gpio_init(void)
305 {
306 	return platform_driver_register(&wm8994_gpio_driver);
307 }
308 subsys_initcall(wm8994_gpio_init);
309 
wm8994_gpio_exit(void)310 static void __exit wm8994_gpio_exit(void)
311 {
312 	platform_driver_unregister(&wm8994_gpio_driver);
313 }
314 module_exit(wm8994_gpio_exit);
315 
316 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
317 MODULE_DESCRIPTION("GPIO interface for WM8994");
318 MODULE_LICENSE("GPL");
319 MODULE_ALIAS("platform:wm8994-gpio");
320