xref: /openbmc/u-boot/drivers/power/regulator/fixed.c (revision e9c847c3)
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 <fdtdec.h>
11 #include <errno.h>
12 #include <dm.h>
13 #include <i2c.h>
14 #include <asm/gpio.h>
15 #include <power/pmic.h>
16 #include <power/regulator.h>
17 
18 DECLARE_GLOBAL_DATA_PTR;
19 
20 struct fixed_regulator_platdata {
21 	struct gpio_desc gpio; /* GPIO for regulator enable control */
22 	unsigned int startup_delay_us;
23 };
24 
25 static int fixed_regulator_ofdata_to_platdata(struct udevice *dev)
26 {
27 	struct dm_regulator_uclass_platdata *uc_pdata;
28 	struct fixed_regulator_platdata *dev_pdata;
29 	struct gpio_desc *gpio;
30 	int ret;
31 
32 	dev_pdata = dev_get_platdata(dev);
33 	uc_pdata = dev_get_uclass_platdata(dev);
34 	if (!uc_pdata)
35 		return -ENXIO;
36 
37 	/* Set type to fixed */
38 	uc_pdata->type = REGULATOR_TYPE_FIXED;
39 
40 	/* Get fixed regulator optional enable GPIO desc */
41 	gpio = &dev_pdata->gpio;
42 	ret = gpio_request_by_name(dev, "gpio", 0, gpio, GPIOD_IS_OUT);
43 	if (ret) {
44 		debug("Fixed regulator optional enable GPIO - not found! Error: %d\n",
45 		      ret);
46 		if (ret != -ENOENT)
47 			return ret;
48 	}
49 
50 	/* Get optional ramp up delay */
51 	dev_pdata->startup_delay_us = fdtdec_get_uint(gd->fdt_blob,
52 						      dev->of_offset,
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 bool 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 	/* Enable GPIO is optional */
107 	if (!dev_pdata->gpio.dev) {
108 		if (!enable)
109 			return -ENOSYS;
110 		return 0;
111 	}
112 
113 	ret = dm_gpio_set_value(&dev_pdata->gpio, enable);
114 	if (ret) {
115 		error("Can't set regulator : %s gpio to: %d\n", dev->name,
116 		      enable);
117 		return ret;
118 	}
119 
120 	if (enable && dev_pdata->startup_delay_us)
121 		udelay(dev_pdata->startup_delay_us);
122 
123 	return 0;
124 }
125 
126 static const struct dm_regulator_ops fixed_regulator_ops = {
127 	.get_value	= fixed_regulator_get_value,
128 	.get_current	= fixed_regulator_get_current,
129 	.get_enable	= fixed_regulator_get_enable,
130 	.set_enable	= fixed_regulator_set_enable,
131 };
132 
133 static const struct udevice_id fixed_regulator_ids[] = {
134 	{ .compatible = "regulator-fixed" },
135 	{ },
136 };
137 
138 U_BOOT_DRIVER(fixed_regulator) = {
139 	.name = "fixed regulator",
140 	.id = UCLASS_REGULATOR,
141 	.ops = &fixed_regulator_ops,
142 	.of_match = fixed_regulator_ids,
143 	.ofdata_to_platdata = fixed_regulator_ofdata_to_platdata,
144 	.platdata_auto_alloc_size = sizeof(struct fixed_regulator_platdata),
145 };
146