xref: /linux/drivers/gpio/gpio-wm8994.c (revision d7b4e3287ca3a7baf66efd9158498e551a9550da)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * gpiolib support for Wolfson WM8994
4  *
5  * Copyright 2009 Wolfson Microelectronics PLC.
6  *
7  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
8  *
9  */
10 
11 #include <linux/cleanup.h>
12 #include <linux/kernel.h>
13 #include <linux/slab.h>
14 #include <linux/module.h>
15 #include <linux/gpio/driver.h>
16 #include <linux/mfd/core.h>
17 #include <linux/platform_device.h>
18 #include <linux/seq_file.h>
19 #include <linux/regmap.h>
20 
21 #include <linux/mfd/wm8994/core.h>
22 #include <linux/mfd/wm8994/pdata.h>
23 #include <linux/mfd/wm8994/gpio.h>
24 #include <linux/mfd/wm8994/registers.h>
25 
26 struct wm8994_gpio {
27 	struct wm8994 *wm8994;
28 	struct gpio_chip gpio_chip;
29 };
30 
31 static int wm8994_gpio_request(struct gpio_chip *chip, unsigned offset)
32 {
33 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
34 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
35 
36 	switch (wm8994->type) {
37 	case WM8958:
38 		switch (offset) {
39 		case 1:
40 		case 2:
41 		case 3:
42 		case 4:
43 		case 6:
44 			return -EINVAL;
45 		}
46 		break;
47 	default:
48 		break;
49 	}
50 
51 	return 0;
52 }
53 
54 static int wm8994_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
55 {
56 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
57 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
58 
59 	return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
60 			       WM8994_GPN_DIR, WM8994_GPN_DIR);
61 }
62 
63 static int wm8994_gpio_get(struct gpio_chip *chip, unsigned offset)
64 {
65 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
66 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
67 	int ret;
68 
69 	ret = wm8994_reg_read(wm8994, WM8994_GPIO_1 + offset);
70 	if (ret < 0)
71 		return ret;
72 
73 	if (ret & WM8994_GPN_LVL)
74 		return 1;
75 	else
76 		return 0;
77 }
78 
79 static int wm8994_gpio_direction_out(struct gpio_chip *chip,
80 				     unsigned offset, int value)
81 {
82 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
83 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
84 
85 	if (value)
86 		value = WM8994_GPN_LVL;
87 
88 	return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
89 			       WM8994_GPN_DIR | WM8994_GPN_LVL, value);
90 }
91 
92 static void wm8994_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
93 {
94 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
95 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
96 
97 	if (value)
98 		value = WM8994_GPN_LVL;
99 
100 	wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, WM8994_GPN_LVL, value);
101 }
102 
103 static int wm8994_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
104 				  unsigned long config)
105 {
106 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
107 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
108 
109 	switch (pinconf_to_config_param(config)) {
110 	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
111 		return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
112 				       WM8994_GPN_OP_CFG_MASK,
113 				       WM8994_GPN_OP_CFG);
114 	case PIN_CONFIG_DRIVE_PUSH_PULL:
115 		return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
116 				       WM8994_GPN_OP_CFG_MASK, 0);
117 	default:
118 		break;
119 	}
120 
121 	return -ENOTSUPP;
122 }
123 
124 static int wm8994_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
125 {
126 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
127 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
128 
129 	return regmap_irq_get_virq(wm8994->irq_data, offset);
130 }
131 
132 
133 #ifdef CONFIG_DEBUG_FS
134 static const char *wm8994_gpio_fn(u16 fn)
135 {
136 	switch (fn) {
137 	case WM8994_GP_FN_PIN_SPECIFIC:
138 		return "pin-specific";
139 	case WM8994_GP_FN_GPIO:
140 		return "GPIO";
141 	case WM8994_GP_FN_SDOUT:
142 		return "SDOUT";
143 	case WM8994_GP_FN_IRQ:
144 		return "IRQ";
145 	case WM8994_GP_FN_TEMPERATURE:
146 		return "Temperature";
147 	case WM8994_GP_FN_MICBIAS1_DET:
148 		return "MICBIAS1 detect";
149 	case WM8994_GP_FN_MICBIAS1_SHORT:
150 		return "MICBIAS1 short";
151 	case WM8994_GP_FN_MICBIAS2_DET:
152 		return "MICBIAS2 detect";
153 	case WM8994_GP_FN_MICBIAS2_SHORT:
154 		return "MICBIAS2 short";
155 	case WM8994_GP_FN_FLL1_LOCK:
156 		return "FLL1 lock";
157 	case WM8994_GP_FN_FLL2_LOCK:
158 		return "FLL2 lock";
159 	case WM8994_GP_FN_SRC1_LOCK:
160 		return "SRC1 lock";
161 	case WM8994_GP_FN_SRC2_LOCK:
162 		return "SRC2 lock";
163 	case WM8994_GP_FN_DRC1_ACT:
164 		return "DRC1 activity";
165 	case WM8994_GP_FN_DRC2_ACT:
166 		return "DRC2 activity";
167 	case WM8994_GP_FN_DRC3_ACT:
168 		return "DRC3 activity";
169 	case WM8994_GP_FN_WSEQ_STATUS:
170 		return "Write sequencer";
171 	case WM8994_GP_FN_FIFO_ERROR:
172 		return "FIFO error";
173 	case WM8994_GP_FN_OPCLK:
174 		return "OPCLK";
175 	case WM8994_GP_FN_THW:
176 		return "Thermal warning";
177 	case WM8994_GP_FN_DCS_DONE:
178 		return "DC servo";
179 	case WM8994_GP_FN_FLL1_OUT:
180 		return "FLL1 output";
181 	case WM8994_GP_FN_FLL2_OUT:
182 		return "FLL1 output";
183 	default:
184 		return "Unknown";
185 	}
186 }
187 
188 static void wm8994_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
189 {
190 	struct wm8994_gpio *wm8994_gpio = gpiochip_get_data(chip);
191 	struct wm8994 *wm8994 = wm8994_gpio->wm8994;
192 	int i;
193 
194 	for (i = 0; i < chip->ngpio; i++) {
195 		int gpio = i + chip->base;
196 		int reg;
197 
198 		/* We report the GPIO even if it's not requested since
199 		 * we're also reporting things like alternate
200 		 * functions which apply even when the GPIO is not in
201 		 * use as a GPIO.
202 		 */
203 		char *label __free(kfree) = gpiochip_dup_line_label(chip, i);
204 		if (IS_ERR(label)) {
205 			dev_err(wm8994->dev, "Failed to duplicate label\n");
206 			continue;
207 		}
208 
209 		seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio,
210 			   label ?: "Unrequested");
211 
212 		reg = wm8994_reg_read(wm8994, WM8994_GPIO_1 + i);
213 		if (reg < 0) {
214 			dev_err(wm8994->dev,
215 				"GPIO control %d read failed: %d\n",
216 				gpio, reg);
217 			seq_printf(s, "\n");
218 			continue;
219 		}
220 
221 		if (reg & WM8994_GPN_DIR)
222 			seq_printf(s, "in ");
223 		else
224 			seq_printf(s, "out ");
225 
226 		if (reg & WM8994_GPN_PU)
227 			seq_printf(s, "pull up ");
228 
229 		if (reg & WM8994_GPN_PD)
230 			seq_printf(s, "pull down ");
231 
232 		if (reg & WM8994_GPN_POL)
233 			seq_printf(s, "inverted ");
234 		else
235 			seq_printf(s, "noninverted ");
236 
237 		if (reg & WM8994_GPN_OP_CFG)
238 			seq_printf(s, "open drain ");
239 		else
240 			seq_printf(s, "push-pull ");
241 
242 		seq_printf(s, "%s (%x)\n",
243 			   wm8994_gpio_fn(reg & WM8994_GPN_FN_MASK), reg);
244 	}
245 }
246 #else
247 #define wm8994_gpio_dbg_show NULL
248 #endif
249 
250 static const struct gpio_chip template_chip = {
251 	.label			= "wm8994",
252 	.owner			= THIS_MODULE,
253 	.request		= wm8994_gpio_request,
254 	.direction_input	= wm8994_gpio_direction_in,
255 	.get			= wm8994_gpio_get,
256 	.direction_output	= wm8994_gpio_direction_out,
257 	.set			= wm8994_gpio_set,
258 	.set_config		= wm8994_gpio_set_config,
259 	.to_irq			= wm8994_gpio_to_irq,
260 	.dbg_show		= wm8994_gpio_dbg_show,
261 	.can_sleep		= true,
262 };
263 
264 static int wm8994_gpio_probe(struct platform_device *pdev)
265 {
266 	struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent);
267 	struct wm8994_pdata *pdata = dev_get_platdata(wm8994->dev);
268 	struct wm8994_gpio *wm8994_gpio;
269 
270 	wm8994_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8994_gpio),
271 				   GFP_KERNEL);
272 	if (wm8994_gpio == NULL)
273 		return -ENOMEM;
274 
275 	wm8994_gpio->wm8994 = wm8994;
276 	wm8994_gpio->gpio_chip = template_chip;
277 	wm8994_gpio->gpio_chip.ngpio = WM8994_GPIO_MAX;
278 	wm8994_gpio->gpio_chip.parent = &pdev->dev;
279 	if (pdata && pdata->gpio_base)
280 		wm8994_gpio->gpio_chip.base = pdata->gpio_base;
281 	else
282 		wm8994_gpio->gpio_chip.base = -1;
283 
284 	return devm_gpiochip_add_data(&pdev->dev, &wm8994_gpio->gpio_chip, wm8994_gpio);
285 }
286 
287 static struct platform_driver wm8994_gpio_driver = {
288 	.driver.name	= "wm8994-gpio",
289 	.probe		= wm8994_gpio_probe,
290 };
291 
292 static int __init wm8994_gpio_init(void)
293 {
294 	return platform_driver_register(&wm8994_gpio_driver);
295 }
296 subsys_initcall(wm8994_gpio_init);
297 
298 static void __exit wm8994_gpio_exit(void)
299 {
300 	platform_driver_unregister(&wm8994_gpio_driver);
301 }
302 module_exit(wm8994_gpio_exit);
303 
304 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
305 MODULE_DESCRIPTION("GPIO interface for WM8994");
306 MODULE_LICENSE("GPL");
307 MODULE_ALIAS("platform:wm8994-gpio");
308