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
wm8994_gpio_request(struct gpio_chip * chip,unsigned offset)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
wm8994_gpio_direction_in(struct gpio_chip * chip,unsigned offset)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
wm8994_gpio_get(struct gpio_chip * chip,unsigned offset)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
wm8994_gpio_direction_out(struct gpio_chip * chip,unsigned offset,int value)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
wm8994_gpio_set(struct gpio_chip * chip,unsigned offset,int value)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
wm8994_gpio_set_config(struct gpio_chip * chip,unsigned int offset,unsigned long config)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
wm8994_gpio_to_irq(struct gpio_chip * chip,unsigned offset)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
wm8994_gpio_fn(u16 fn)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
wm8994_gpio_dbg_show(struct seq_file * s,struct gpio_chip * chip)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
wm8994_gpio_probe(struct platform_device * pdev)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
wm8994_gpio_init(void)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
wm8994_gpio_exit(void)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