xref: /rk3399_rockchip-uboot/drivers/power/regulator/gpio-regulator.c (revision cd282fabfa8c8526ef4620c4f91e3c5dba03bf29)
1 /*
2  * (C) Copyright 2016 Texas Instruments Incorporated, <www.ti.com>
3  * Keerthy <j-keerthy@ti.com>
4  *
5  * SPDX-License-Identifier:     GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <fdtdec.h>
10 #include <errno.h>
11 #include <dm.h>
12 #include <i2c.h>
13 #include <asm/gpio.h>
14 #include <power/pmic.h>
15 #include <power/regulator.h>
16 
17 #define GPIO_REGULATOR_MAX_STATES	2
18 
19 DECLARE_GLOBAL_DATA_PTR;
20 
21 struct gpio_regulator_platdata {
22 	struct gpio_desc gpio; /* GPIO for regulator voltage control */
23 	int states[GPIO_REGULATOR_MAX_STATES];
24 	int voltages[GPIO_REGULATOR_MAX_STATES];
25 };
26 
27 static int gpio_regulator_ofdata_to_platdata(struct udevice *dev)
28 {
29 	struct dm_regulator_uclass_platdata *uc_pdata;
30 	struct gpio_regulator_platdata *dev_pdata;
31 	struct gpio_desc *gpio;
32 	const void *blob = gd->fdt_blob;
33 	int ret, count, i, j;
34 	u32 states_array[8];
35 
36 	dev_pdata = dev_get_platdata(dev);
37 	uc_pdata = dev_get_uclass_platdata(dev);
38 	if (!uc_pdata)
39 		return -ENXIO;
40 
41 	/* Set type to gpio */
42 	uc_pdata->type = REGULATOR_TYPE_GPIO;
43 
44 	/*
45 	 * Get gpio regulator gpio desc
46 	 * Assuming one GPIO per regulator.
47 	 * Can be extended later to multiple GPIOs
48 	 * per gpio-regulator. As of now no instance with multiple
49 	 * gpios is presnt
50 	 */
51 	gpio = &dev_pdata->gpio;
52 	ret = gpio_request_by_name(dev, "gpios", 0, gpio, GPIOD_IS_OUT);
53 	if (ret)
54 		debug("regulator gpio - not found! Error: %d", ret);
55 
56 	blob = dev_read_prop(dev, "states", &count);
57 	if (!blob)
58 		return -EINVAL;
59 
60 	ret = dev_read_u32_array(dev, "states", states_array, count / 4);
61 	if (ret)
62 		return -EINVAL;
63 
64 	for (i = 0, j = 0; i < count / 4; i += 2) {
65 		dev_pdata->voltages[j] = states_array[i];
66 		dev_pdata->states[j] = states_array[i + 1];
67 		j++;
68 	}
69 
70 	return 0;
71 }
72 
73 static int gpio_regulator_get_value(struct udevice *dev)
74 {
75 	struct dm_regulator_uclass_platdata *uc_pdata;
76 	struct gpio_regulator_platdata *dev_pdata = dev_get_platdata(dev);
77 	int enable;
78 
79 	if (!dev_pdata->gpio.dev)
80 		return -ENOSYS;
81 
82 	uc_pdata = dev_get_uclass_platdata(dev);
83 	if (uc_pdata->min_uV > uc_pdata->max_uV) {
84 		debug("Invalid constraints for: %s\n", uc_pdata->name);
85 		return -EINVAL;
86 	}
87 
88 	enable = dm_gpio_get_value(&dev_pdata->gpio);
89 	if (enable == dev_pdata->states[0])
90 		return dev_pdata->voltages[0];
91 	else
92 		return dev_pdata->voltages[1];
93 }
94 
95 static int gpio_regulator_set_value(struct udevice *dev, int uV)
96 {
97 	struct gpio_regulator_platdata *dev_pdata = dev_get_platdata(dev);
98 	int ret;
99 	bool enable;
100 
101 	if (!dev_pdata->gpio.dev)
102 		return -ENOSYS;
103 
104 	if (uV == dev_pdata->voltages[0])
105 		enable = dev_pdata->states[0];
106 	else if (uV == dev_pdata->voltages[1])
107 		enable = dev_pdata->states[1];
108 	else
109 		return -EINVAL;
110 
111 	ret = dm_gpio_set_value(&dev_pdata->gpio, enable);
112 	if (ret) {
113 		pr_err("Can't set regulator : %s gpio to: %d\n", dev->name,
114 		      enable);
115 		return ret;
116 	}
117 
118 	return 0;
119 }
120 
121 static const struct dm_regulator_ops gpio_regulator_ops = {
122 	.get_value	= gpio_regulator_get_value,
123 	.set_value	= gpio_regulator_set_value,
124 };
125 
126 static const struct udevice_id gpio_regulator_ids[] = {
127 	{ .compatible = "regulator-gpio" },
128 	{ },
129 };
130 
131 U_BOOT_DRIVER(gpio_regulator) = {
132 	.name = "gpio regulator",
133 	.id = UCLASS_REGULATOR,
134 	.ops = &gpio_regulator_ops,
135 	.of_match = gpio_regulator_ids,
136 	.ofdata_to_platdata = gpio_regulator_ofdata_to_platdata,
137 	.platdata_auto_alloc_size = sizeof(struct gpio_regulator_platdata),
138 };
139