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
26struct wm8994_gpio {
27	struct wm8994 *wm8994;
28	struct gpio_chip gpio_chip;
29};
30
31static 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
54static 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
63static 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
79static 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
92static 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
103static 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
124static 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
134static 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
188static 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
250static 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
264static 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
287static struct platform_driver wm8994_gpio_driver = {
288	.driver.name	= "wm8994-gpio",
289	.probe		= wm8994_gpio_probe,
290};
291
292static int __init wm8994_gpio_init(void)
293{
294	return platform_driver_register(&wm8994_gpio_driver);
295}
296subsys_initcall(wm8994_gpio_init);
297
298static void __exit wm8994_gpio_exit(void)
299{
300	platform_driver_unregister(&wm8994_gpio_driver);
301}
302module_exit(wm8994_gpio_exit);
303
304MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
305MODULE_DESCRIPTION("GPIO interface for WM8994");
306MODULE_LICENSE("GPL");
307MODULE_ALIAS("platform:wm8994-gpio");
308