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