1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * gpiolib support for Wolfson WM835x PMICs
4  *
5  * Copyright 2009 Wolfson Microelectronics PLC.
6  *
7  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
8  *
9  */
10 
11 #include <linux/gpio/driver.h>
12 #include <linux/kernel.h>
13 #include <linux/mfd/core.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/slab.h>
17 
18 #include <linux/mfd/wm8350/core.h>
19 #include <linux/mfd/wm8350/gpio.h>
20 
21 struct wm8350_gpio_data {
22 	struct wm8350 *wm8350;
23 	struct gpio_chip gpio_chip;
24 };
25 
wm8350_gpio_direction_in(struct gpio_chip * chip,unsigned offset)26 static int wm8350_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
27 {
28 	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
29 	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
30 
31 	return wm8350_set_bits(wm8350, WM8350_GPIO_CONFIGURATION_I_O,
32 			       1 << offset);
33 }
34 
wm8350_gpio_get(struct gpio_chip * chip,unsigned offset)35 static int wm8350_gpio_get(struct gpio_chip *chip, unsigned offset)
36 {
37 	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
38 	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
39 	int ret;
40 
41 	ret = wm8350_reg_read(wm8350, WM8350_GPIO_LEVEL);
42 	if (ret < 0)
43 		return ret;
44 
45 	if (ret & (1 << offset))
46 		return 1;
47 	else
48 		return 0;
49 }
50 
wm8350_gpio_set(struct gpio_chip * chip,unsigned offset,int value)51 static void wm8350_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
52 {
53 	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
54 	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
55 
56 	if (value)
57 		wm8350_set_bits(wm8350, WM8350_GPIO_LEVEL, 1 << offset);
58 	else
59 		wm8350_clear_bits(wm8350, WM8350_GPIO_LEVEL, 1 << offset);
60 }
61 
wm8350_gpio_direction_out(struct gpio_chip * chip,unsigned offset,int value)62 static int wm8350_gpio_direction_out(struct gpio_chip *chip,
63 				     unsigned offset, int value)
64 {
65 	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
66 	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
67 	int ret;
68 
69 	ret = wm8350_clear_bits(wm8350, WM8350_GPIO_CONFIGURATION_I_O,
70 				1 << offset);
71 	if (ret < 0)
72 		return ret;
73 
74 	/* Don't have an atomic direction/value setup */
75 	wm8350_gpio_set(chip, offset, value);
76 
77 	return 0;
78 }
79 
wm8350_gpio_to_irq(struct gpio_chip * chip,unsigned offset)80 static int wm8350_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
81 {
82 	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
83 	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
84 
85 	if (!wm8350->irq_base)
86 		return -EINVAL;
87 
88 	return wm8350->irq_base + WM8350_IRQ_GPIO(offset);
89 }
90 
91 static const struct gpio_chip template_chip = {
92 	.label			= "wm8350",
93 	.owner			= THIS_MODULE,
94 	.direction_input	= wm8350_gpio_direction_in,
95 	.get			= wm8350_gpio_get,
96 	.direction_output	= wm8350_gpio_direction_out,
97 	.set			= wm8350_gpio_set,
98 	.to_irq			= wm8350_gpio_to_irq,
99 	.can_sleep		= true,
100 };
101 
wm8350_gpio_probe(struct platform_device * pdev)102 static int wm8350_gpio_probe(struct platform_device *pdev)
103 {
104 	struct wm8350 *wm8350 = dev_get_drvdata(pdev->dev.parent);
105 	struct wm8350_platform_data *pdata = dev_get_platdata(wm8350->dev);
106 	struct wm8350_gpio_data *wm8350_gpio;
107 
108 	wm8350_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8350_gpio),
109 				   GFP_KERNEL);
110 	if (wm8350_gpio == NULL)
111 		return -ENOMEM;
112 
113 	wm8350_gpio->wm8350 = wm8350;
114 	wm8350_gpio->gpio_chip = template_chip;
115 	wm8350_gpio->gpio_chip.ngpio = 13;
116 	wm8350_gpio->gpio_chip.parent = &pdev->dev;
117 	if (pdata && pdata->gpio_base)
118 		wm8350_gpio->gpio_chip.base = pdata->gpio_base;
119 	else
120 		wm8350_gpio->gpio_chip.base = -1;
121 
122 	return devm_gpiochip_add_data(&pdev->dev, &wm8350_gpio->gpio_chip, wm8350_gpio);
123 }
124 
125 static struct platform_driver wm8350_gpio_driver = {
126 	.driver.name	= "wm8350-gpio",
127 	.probe		= wm8350_gpio_probe,
128 };
129 
wm8350_gpio_init(void)130 static int __init wm8350_gpio_init(void)
131 {
132 	return platform_driver_register(&wm8350_gpio_driver);
133 }
134 subsys_initcall(wm8350_gpio_init);
135 
wm8350_gpio_exit(void)136 static void __exit wm8350_gpio_exit(void)
137 {
138 	platform_driver_unregister(&wm8350_gpio_driver);
139 }
140 module_exit(wm8350_gpio_exit);
141 
142 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
143 MODULE_DESCRIPTION("GPIO interface for WM8350 PMICs");
144 MODULE_LICENSE("GPL");
145 MODULE_ALIAS("platform:wm8350-gpio");
146