xref: /linux/drivers/regulator/rohm-regulator.c (revision 249ebf3f65f8530beb2cbfb91bff1d83ba88d23c)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2020 ROHM Semiconductors
3 
4 #include <linux/errno.h>
5 #include <linux/mfd/rohm-generic.h>
6 #include <linux/module.h>
7 #include <linux/of.h>
8 #include <linux/regmap.h>
9 #include <linux/regulator/driver.h>
10 
11 static int set_dvs_level(const struct regulator_desc *desc,
12 			 struct device_node *np, struct regmap *regmap,
13 			 char *prop, unsigned int reg, unsigned int mask,
14 			 unsigned int omask, unsigned int oreg)
15 {
16 	int ret, i;
17 	uint32_t uv;
18 
19 	ret = of_property_read_u32(np, prop, &uv);
20 	if (ret) {
21 		if (ret != -EINVAL)
22 			return ret;
23 		return 0;
24 	}
25 	/* If voltage is set to 0 => disable */
26 	if (uv == 0) {
27 		if (omask)
28 			return regmap_update_bits(regmap, oreg, omask, 0);
29 	}
30 	/* Some setups don't allow setting own voltage but do allow enabling */
31 	if (!mask) {
32 		if (omask)
33 			return regmap_update_bits(regmap, oreg, omask, omask);
34 
35 		return -EINVAL;
36 	}
37 	for (i = 0; i < desc->n_voltages; i++) {
38 		/* NOTE to next hacker - Does not support pickable ranges */
39 		if (desc->linear_range_selectors_bitfield)
40 			return -EINVAL;
41 		if (desc->n_linear_ranges)
42 			ret = regulator_desc_list_voltage_linear_range(desc, i);
43 		else
44 			ret = regulator_desc_list_voltage_linear(desc, i);
45 		if (ret < 0)
46 			continue;
47 		if (ret == uv) {
48 			i <<= ffs(desc->vsel_mask) - 1;
49 
50 			ret = regmap_update_bits(regmap, reg, mask, i);
51 			if (omask && !ret)
52 				ret = regmap_update_bits(regmap, oreg, omask,
53 							 omask);
54 			break;
55 		}
56 	}
57 	if (i == desc->n_voltages)
58 		pr_warn("Unsupported %s voltage %u\n", prop, uv);
59 
60 	return ret;
61 }
62 
63 int rohm_regulator_set_dvs_levels(const struct rohm_dvs_config *dvs,
64 			  struct device_node *np,
65 			  const struct regulator_desc *desc,
66 			  struct regmap *regmap)
67 {
68 	int i, ret = 0;
69 	char *prop;
70 	unsigned int reg, mask, omask, oreg = desc->enable_reg;
71 
72 	for (i = 0; i < ROHM_DVS_LEVEL_VALID_AMOUNT && !ret; i++) {
73 		int bit;
74 
75 		bit = BIT(i);
76 		if (dvs->level_map & bit) {
77 			switch (bit) {
78 			case ROHM_DVS_LEVEL_RUN:
79 				prop = "rohm,dvs-run-voltage";
80 				reg = dvs->run_reg;
81 				mask = dvs->run_mask;
82 				omask = dvs->run_on_mask;
83 				break;
84 			case ROHM_DVS_LEVEL_IDLE:
85 				prop = "rohm,dvs-idle-voltage";
86 				reg = dvs->idle_reg;
87 				mask = dvs->idle_mask;
88 				omask = dvs->idle_on_mask;
89 				break;
90 			case ROHM_DVS_LEVEL_SUSPEND:
91 				prop = "rohm,dvs-suspend-voltage";
92 				reg = dvs->suspend_reg;
93 				mask = dvs->suspend_mask;
94 				omask = dvs->suspend_on_mask;
95 				break;
96 			case ROHM_DVS_LEVEL_LPSR:
97 				prop = "rohm,dvs-lpsr-voltage";
98 				reg = dvs->lpsr_reg;
99 				mask = dvs->lpsr_mask;
100 				omask = dvs->lpsr_on_mask;
101 				break;
102 			case ROHM_DVS_LEVEL_SNVS:
103 				prop = "rohm,dvs-snvs-voltage";
104 				reg = dvs->snvs_reg;
105 				mask = dvs->snvs_mask;
106 				omask = dvs->snvs_on_mask;
107 				break;
108 			default:
109 				return -EINVAL;
110 			}
111 			ret = set_dvs_level(desc, np, regmap, prop, reg, mask,
112 					    omask, oreg);
113 		}
114 	}
115 	return ret;
116 }
117 EXPORT_SYMBOL(rohm_regulator_set_dvs_levels);
118 
119 /*
120  * Few ROHM PMIC ICs have constrains on voltage changing:
121  * BD71837 - only buck 1-4 voltages can be changed when they are enabled.
122  * Other bucks and all LDOs must be disabled when voltage is changed.
123  * BD96801 - LDO voltage levels can be changed when LDOs are disabled.
124  */
125 int rohm_regulator_set_voltage_sel_restricted(struct regulator_dev *rdev,
126 					      unsigned int sel)
127 {
128 	if (rdev->desc->ops->is_enabled(rdev))
129 		return -EBUSY;
130 
131 	return regulator_set_voltage_sel_regmap(rdev, sel);
132 }
133 EXPORT_SYMBOL_GPL(rohm_regulator_set_voltage_sel_restricted);
134 
135 MODULE_LICENSE("GPL v2");
136 MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
137 MODULE_DESCRIPTION("Generic helpers for ROHM PMIC regulator drivers");
138