xref: /openbmc/u-boot/drivers/power/regulator/fixed.c (revision d024236e5a31a2b4b82cbcc98b31b8170fc88d28)
1 /*
2  *  Copyright (C) 2015 Samsung Electronics
3  *
4  *  Przemyslaw Marczak <p.marczak@samsung.com>
5  *
6  * SPDX-License-Identifier:	GPL-2.0+
7  */
8 
9 #include <common.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 struct fixed_regulator_platdata {
18 	struct gpio_desc gpio; /* GPIO for regulator enable control */
19 	unsigned int startup_delay_us;
20 };
21 
22 static int fixed_regulator_ofdata_to_platdata(struct udevice *dev)
23 {
24 	struct dm_regulator_uclass_platdata *uc_pdata;
25 	struct fixed_regulator_platdata *dev_pdata;
26 	struct gpio_desc *gpio;
27 	int flags = GPIOD_IS_OUT;
28 	int ret;
29 
30 	dev_pdata = dev_get_platdata(dev);
31 	uc_pdata = dev_get_uclass_platdata(dev);
32 	if (!uc_pdata)
33 		return -ENXIO;
34 
35 	/* Set type to fixed */
36 	uc_pdata->type = REGULATOR_TYPE_FIXED;
37 
38 	if (dev_read_bool(dev, "enable-active-high"))
39 		flags |= GPIOD_IS_OUT_ACTIVE;
40 
41 	/* Get fixed regulator optional enable GPIO desc */
42 	gpio = &dev_pdata->gpio;
43 	ret = gpio_request_by_name(dev, "gpio", 0, gpio, flags);
44 	if (ret) {
45 		debug("Fixed regulator optional enable GPIO - not found! Error: %d\n",
46 		      ret);
47 		if (ret != -ENOENT)
48 			return ret;
49 	}
50 
51 	/* Get optional ramp up delay */
52 	dev_pdata->startup_delay_us = dev_read_u32_default(dev,
53 							"startup-delay-us", 0);
54 
55 	return 0;
56 }
57 
58 static int fixed_regulator_get_value(struct udevice *dev)
59 {
60 	struct dm_regulator_uclass_platdata *uc_pdata;
61 
62 	uc_pdata = dev_get_uclass_platdata(dev);
63 	if (!uc_pdata)
64 		return -ENXIO;
65 
66 	if (uc_pdata->min_uV != uc_pdata->max_uV) {
67 		debug("Invalid constraints for: %s\n", uc_pdata->name);
68 		return -EINVAL;
69 	}
70 
71 	return uc_pdata->min_uV;
72 }
73 
74 static int fixed_regulator_get_current(struct udevice *dev)
75 {
76 	struct dm_regulator_uclass_platdata *uc_pdata;
77 
78 	uc_pdata = dev_get_uclass_platdata(dev);
79 	if (!uc_pdata)
80 		return -ENXIO;
81 
82 	if (uc_pdata->min_uA != uc_pdata->max_uA) {
83 		debug("Invalid constraints for: %s\n", uc_pdata->name);
84 		return -EINVAL;
85 	}
86 
87 	return uc_pdata->min_uA;
88 }
89 
90 static int fixed_regulator_get_enable(struct udevice *dev)
91 {
92 	struct fixed_regulator_platdata *dev_pdata = dev_get_platdata(dev);
93 
94 	/* Enable GPIO is optional */
95 	if (!dev_pdata->gpio.dev)
96 		return true;
97 
98 	return dm_gpio_get_value(&dev_pdata->gpio);
99 }
100 
101 static int fixed_regulator_set_enable(struct udevice *dev, bool enable)
102 {
103 	struct fixed_regulator_platdata *dev_pdata = dev_get_platdata(dev);
104 	int ret;
105 
106 	debug("%s: dev='%s', enable=%d, delay=%d, has_gpio=%d\n", __func__,
107 	      dev->name, enable, dev_pdata->startup_delay_us,
108 	      dm_gpio_is_valid(&dev_pdata->gpio));
109 	/* Enable GPIO is optional */
110 	if (!dm_gpio_is_valid(&dev_pdata->gpio)) {
111 		if (!enable)
112 			return -ENOSYS;
113 		return 0;
114 	}
115 
116 	ret = dm_gpio_set_value(&dev_pdata->gpio, enable);
117 	if (ret) {
118 		pr_err("Can't set regulator : %s gpio to: %d\n", dev->name,
119 		      enable);
120 		return ret;
121 	}
122 
123 	if (enable && dev_pdata->startup_delay_us)
124 		udelay(dev_pdata->startup_delay_us);
125 	debug("%s: done\n", __func__);
126 
127 	return 0;
128 }
129 
130 static const struct dm_regulator_ops fixed_regulator_ops = {
131 	.get_value	= fixed_regulator_get_value,
132 	.get_current	= fixed_regulator_get_current,
133 	.get_enable	= fixed_regulator_get_enable,
134 	.set_enable	= fixed_regulator_set_enable,
135 };
136 
137 static const struct udevice_id fixed_regulator_ids[] = {
138 	{ .compatible = "regulator-fixed" },
139 	{ },
140 };
141 
142 U_BOOT_DRIVER(fixed_regulator) = {
143 	.name = "fixed regulator",
144 	.id = UCLASS_REGULATOR,
145 	.ops = &fixed_regulator_ops,
146 	.of_match = fixed_regulator_ids,
147 	.ofdata_to_platdata = fixed_regulator_ofdata_to_platdata,
148 	.platdata_auto_alloc_size = sizeof(struct fixed_regulator_platdata),
149 };
150