1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2019 Disruptive Technologies Research AS
4 * Sven Schwermer <sven.svenschwermer@disruptive-technologies.com>
5 */
6
7 #include <dm.h>
8 #include <log.h>
9 #include <asm/gpio.h>
10 #include <linux/delay.h>
11 #include <power/regulator.h>
12 #include "regulator_common.h"
13
14 #include "regulator_common.h"
15
regulator_common_of_to_plat(struct udevice * dev,struct regulator_common_plat * plat,const char * enable_gpio_name)16 int regulator_common_of_to_plat(struct udevice *dev,
17 struct regulator_common_plat *plat,
18 const char *enable_gpio_name)
19 {
20 struct gpio_desc *gpio;
21 int flags = GPIOD_IS_OUT;
22 int ret;
23
24 if (!dev_read_bool(dev, "enable-active-high"))
25 flags |= GPIOD_ACTIVE_LOW;
26 if (dev_read_bool(dev, "regulator-boot-on"))
27 flags |= GPIOD_IS_OUT_ACTIVE;
28
29 /* Get optional enable GPIO desc */
30 gpio = &plat->gpio;
31 ret = gpio_request_by_name(dev, enable_gpio_name, 0, gpio, flags);
32 if (ret) {
33 debug("Regulator '%s' optional enable GPIO - not found! Error: %d\n",
34 dev->name, ret);
35 if (ret != -ENOENT)
36 return ret;
37 }
38
39 /* Get optional ramp up delay */
40 plat->startup_delay_us = dev_read_u32_default(dev,
41 "startup-delay-us", 0);
42 plat->off_on_delay_us = dev_read_u32_default(dev, "off-on-delay-us", 0);
43 if (!plat->off_on_delay_us) {
44 plat->off_on_delay_us =
45 dev_read_u32_default(dev, "u-boot,off-on-delay-us", 0);
46 }
47
48 return 0;
49 }
50
regulator_common_get_enable(const struct udevice * dev,struct regulator_common_plat * plat)51 int regulator_common_get_enable(const struct udevice *dev,
52 struct regulator_common_plat *plat)
53 {
54 /* Enable GPIO is optional */
55 if (!plat->gpio.dev)
56 return true;
57
58 return dm_gpio_get_value(&plat->gpio);
59 }
60
regulator_common_set_enable(const struct udevice * dev,struct regulator_common_plat * plat,bool enable)61 int regulator_common_set_enable(const struct udevice *dev,
62 struct regulator_common_plat *plat, bool enable)
63 {
64 int ret;
65
66 debug("%s: dev='%s', enable=%d, delay=%d, has_gpio=%d\n", __func__,
67 dev->name, enable, plat->startup_delay_us,
68 dm_gpio_is_valid(&plat->gpio));
69 /* Enable GPIO is optional */
70 if (!dm_gpio_is_valid(&plat->gpio)) {
71 if (!enable)
72 return -ENOSYS;
73 return 0;
74 }
75
76 /* If previously enabled, increase count */
77 if (enable && plat->enable_count > 0) {
78 plat->enable_count++;
79 return -EALREADY;
80 }
81
82 if (!enable) {
83 if (plat->enable_count > 1) {
84 /* If enabled multiple times, decrease count */
85 plat->enable_count--;
86 return -EBUSY;
87 } else if (!plat->enable_count) {
88 /* If already disabled, do nothing */
89 return -EALREADY;
90 }
91 }
92
93 ret = dm_gpio_set_value(&plat->gpio, enable);
94 if (ret) {
95 pr_err("Can't set regulator : %s gpio to: %d\n", dev->name,
96 enable);
97 return ret;
98 }
99
100 if (enable && plat->startup_delay_us)
101 udelay(plat->startup_delay_us);
102 debug("%s: done\n", __func__);
103
104 if (!enable && plat->off_on_delay_us)
105 udelay(plat->off_on_delay_us);
106
107 if (enable)
108 plat->enable_count++;
109 else
110 plat->enable_count--;
111
112 return 0;
113 }
114