xref: /openbmc/u-boot/drivers/power/regulator/fixed.c (revision e47b2d67)
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 	const void *blob = gd->fdt_blob;
31 	int node = dev_of_offset(dev), flags = GPIOD_IS_OUT;
32 	int ret;
33 
34 	dev_pdata = dev_get_platdata(dev);
35 	uc_pdata = dev_get_uclass_platdata(dev);
36 	if (!uc_pdata)
37 		return -ENXIO;
38 
39 	/* Set type to fixed */
40 	uc_pdata->type = REGULATOR_TYPE_FIXED;
41 
42 	if (fdtdec_get_bool(blob, node, "enable-active-high"))
43 		flags |= GPIOD_IS_OUT_ACTIVE;
44 
45 	/* Get fixed regulator optional enable GPIO desc */
46 	gpio = &dev_pdata->gpio;
47 	ret = gpio_request_by_name(dev, "gpio", 0, gpio, flags);
48 	if (ret) {
49 		debug("Fixed regulator optional enable GPIO - not found! Error: %d\n",
50 		      ret);
51 		if (ret != -ENOENT)
52 			return ret;
53 	}
54 
55 	/* Get optional ramp up delay */
56 	dev_pdata->startup_delay_us = fdtdec_get_uint(gd->fdt_blob,
57 						      dev_of_offset(dev),
58 						      "startup-delay-us", 0);
59 
60 	return 0;
61 }
62 
63 static int fixed_regulator_get_value(struct udevice *dev)
64 {
65 	struct dm_regulator_uclass_platdata *uc_pdata;
66 
67 	uc_pdata = dev_get_uclass_platdata(dev);
68 	if (!uc_pdata)
69 		return -ENXIO;
70 
71 	if (uc_pdata->min_uV != uc_pdata->max_uV) {
72 		debug("Invalid constraints for: %s\n", uc_pdata->name);
73 		return -EINVAL;
74 	}
75 
76 	return uc_pdata->min_uV;
77 }
78 
79 static int fixed_regulator_get_current(struct udevice *dev)
80 {
81 	struct dm_regulator_uclass_platdata *uc_pdata;
82 
83 	uc_pdata = dev_get_uclass_platdata(dev);
84 	if (!uc_pdata)
85 		return -ENXIO;
86 
87 	if (uc_pdata->min_uA != uc_pdata->max_uA) {
88 		debug("Invalid constraints for: %s\n", uc_pdata->name);
89 		return -EINVAL;
90 	}
91 
92 	return uc_pdata->min_uA;
93 }
94 
95 static bool fixed_regulator_get_enable(struct udevice *dev)
96 {
97 	struct fixed_regulator_platdata *dev_pdata = dev_get_platdata(dev);
98 
99 	/* Enable GPIO is optional */
100 	if (!dev_pdata->gpio.dev)
101 		return true;
102 
103 	return dm_gpio_get_value(&dev_pdata->gpio);
104 }
105 
106 static int fixed_regulator_set_enable(struct udevice *dev, bool enable)
107 {
108 	struct fixed_regulator_platdata *dev_pdata = dev_get_platdata(dev);
109 	int ret;
110 
111 	/* Enable GPIO is optional */
112 	if (!dev_pdata->gpio.dev) {
113 		if (!enable)
114 			return -ENOSYS;
115 		return 0;
116 	}
117 
118 	ret = dm_gpio_set_value(&dev_pdata->gpio, enable);
119 	if (ret) {
120 		error("Can't set regulator : %s gpio to: %d\n", dev->name,
121 		      enable);
122 		return ret;
123 	}
124 
125 	if (enable && dev_pdata->startup_delay_us)
126 		udelay(dev_pdata->startup_delay_us);
127 
128 	return 0;
129 }
130 
131 static const struct dm_regulator_ops fixed_regulator_ops = {
132 	.get_value	= fixed_regulator_get_value,
133 	.get_current	= fixed_regulator_get_current,
134 	.get_enable	= fixed_regulator_get_enable,
135 	.set_enable	= fixed_regulator_set_enable,
136 };
137 
138 static const struct udevice_id fixed_regulator_ids[] = {
139 	{ .compatible = "regulator-fixed" },
140 	{ },
141 };
142 
143 U_BOOT_DRIVER(fixed_regulator) = {
144 	.name = "fixed regulator",
145 	.id = UCLASS_REGULATOR,
146 	.ops = &fixed_regulator_ops,
147 	.of_match = fixed_regulator_ids,
148 	.ofdata_to_platdata = fixed_regulator_ofdata_to_platdata,
149 	.platdata_auto_alloc_size = sizeof(struct fixed_regulator_platdata),
150 };
151