1 /*
2  * pbias-regulator.c
3  *
4  * Copyright (C) 2014 Texas Instruments Incorporated - https://www.ti.com/
5  * Author: Balaji T K <balajitk@ti.com>
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License as
9  * published by the Free Software Foundation version 2.
10  *
11  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
12  * kind, whether express or implied; without even the implied warranty
13  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 
17 #include <linux/err.h>
18 #include <linux/io.h>
19 #include <linux/module.h>
20 #include <linux/mfd/syscon.h>
21 #include <linux/platform_device.h>
22 #include <linux/regulator/driver.h>
23 #include <linux/regulator/machine.h>
24 #include <linux/regulator/of_regulator.h>
25 #include <linux/regmap.h>
26 #include <linux/slab.h>
27 #include <linux/of.h>
28 #include <linux/of_device.h>
29 
30 struct pbias_reg_info {
31 	u32 enable;
32 	u32 enable_mask;
33 	u32 disable_val;
34 	u32 vmode;
35 	unsigned int enable_time;
36 	char *name;
37 	const unsigned int *pbias_volt_table;
38 	int n_voltages;
39 };
40 
41 struct pbias_of_data {
42 	unsigned int offset;
43 };
44 
45 static const unsigned int pbias_volt_table_3_0V[] = {
46 	1800000,
47 	3000000
48 };
49 
50 static const unsigned int pbias_volt_table_3_3V[] = {
51 	1800000,
52 	3300000
53 };
54 
55 static const struct regulator_ops pbias_regulator_voltage_ops = {
56 	.list_voltage = regulator_list_voltage_table,
57 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
58 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
59 	.enable = regulator_enable_regmap,
60 	.disable = regulator_disable_regmap,
61 	.is_enabled = regulator_is_enabled_regmap,
62 };
63 
64 static const struct pbias_reg_info pbias_mmc_omap2430 = {
65 	.enable = BIT(1),
66 	.enable_mask = BIT(1),
67 	.vmode = BIT(0),
68 	.disable_val = 0,
69 	.enable_time = 100,
70 	.pbias_volt_table = pbias_volt_table_3_0V,
71 	.n_voltages = 2,
72 	.name = "pbias_mmc_omap2430"
73 };
74 
75 static const struct pbias_reg_info pbias_sim_omap3 = {
76 	.enable = BIT(9),
77 	.enable_mask = BIT(9),
78 	.vmode = BIT(8),
79 	.enable_time = 100,
80 	.pbias_volt_table = pbias_volt_table_3_0V,
81 	.n_voltages = 2,
82 	.name = "pbias_sim_omap3"
83 };
84 
85 static const struct pbias_reg_info pbias_mmc_omap4 = {
86 	.enable = BIT(26) | BIT(22),
87 	.enable_mask = BIT(26) | BIT(25) | BIT(22),
88 	.disable_val = BIT(25),
89 	.vmode = BIT(21),
90 	.enable_time = 100,
91 	.pbias_volt_table = pbias_volt_table_3_0V,
92 	.n_voltages = 2,
93 	.name = "pbias_mmc_omap4"
94 };
95 
96 static const struct pbias_reg_info pbias_mmc_omap5 = {
97 	.enable = BIT(27) | BIT(26),
98 	.enable_mask = BIT(27) | BIT(25) | BIT(26),
99 	.disable_val = BIT(25),
100 	.vmode = BIT(21),
101 	.enable_time = 100,
102 	.pbias_volt_table = pbias_volt_table_3_3V,
103 	.n_voltages = 2,
104 	.name = "pbias_mmc_omap5"
105 };
106 
107 static struct of_regulator_match pbias_matches[] = {
108 	{ .name = "pbias_mmc_omap2430", .driver_data = (void *)&pbias_mmc_omap2430},
109 	{ .name = "pbias_sim_omap3", .driver_data = (void *)&pbias_sim_omap3},
110 	{ .name = "pbias_mmc_omap4", .driver_data = (void *)&pbias_mmc_omap4},
111 	{ .name = "pbias_mmc_omap5", .driver_data = (void *)&pbias_mmc_omap5},
112 };
113 #define PBIAS_NUM_REGS	ARRAY_SIZE(pbias_matches)
114 
115 /* Offset from SCM general area (and syscon) base */
116 
117 static const struct pbias_of_data pbias_of_data_omap2 = {
118 	.offset = 0x230,
119 };
120 
121 static const struct pbias_of_data pbias_of_data_omap3 = {
122 	.offset = 0x2b0,
123 };
124 
125 static const struct pbias_of_data pbias_of_data_omap4 = {
126 	.offset = 0x60,
127 };
128 
129 static const struct pbias_of_data pbias_of_data_omap5 = {
130 	.offset = 0x60,
131 };
132 
133 static const struct pbias_of_data pbias_of_data_dra7 = {
134 	.offset = 0xe00,
135 };
136 
137 static const struct of_device_id pbias_of_match[] = {
138 	{ .compatible = "ti,pbias-omap", },
139 	{ .compatible = "ti,pbias-omap2", .data = &pbias_of_data_omap2, },
140 	{ .compatible = "ti,pbias-omap3", .data = &pbias_of_data_omap3, },
141 	{ .compatible = "ti,pbias-omap4", .data = &pbias_of_data_omap4, },
142 	{ .compatible = "ti,pbias-omap5", .data = &pbias_of_data_omap5, },
143 	{ .compatible = "ti,pbias-dra7", .data = &pbias_of_data_dra7, },
144 	{},
145 };
146 MODULE_DEVICE_TABLE(of, pbias_of_match);
147 
pbias_regulator_probe(struct platform_device * pdev)148 static int pbias_regulator_probe(struct platform_device *pdev)
149 {
150 	struct device_node *np = pdev->dev.of_node;
151 	struct resource *res;
152 	struct regulator_config cfg = { };
153 	struct regulator_desc *desc;
154 	struct regulator_dev *rdev;
155 	struct regmap *syscon;
156 	const struct pbias_reg_info *info;
157 	int ret, count, idx;
158 	const struct pbias_of_data *data;
159 	unsigned int offset;
160 
161 	count = of_regulator_match(&pdev->dev, np, pbias_matches,
162 						PBIAS_NUM_REGS);
163 	if (count < 0)
164 		return count;
165 
166 	desc = devm_kcalloc(&pdev->dev, count, sizeof(*desc), GFP_KERNEL);
167 	if (!desc)
168 		return -ENOMEM;
169 
170 	syscon = syscon_regmap_lookup_by_phandle(np, "syscon");
171 	if (IS_ERR(syscon))
172 		return PTR_ERR(syscon);
173 
174 	data = of_device_get_match_data(&pdev->dev);
175 	if (data) {
176 		offset = data->offset;
177 	} else {
178 		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
179 		if (!res)
180 			return -EINVAL;
181 
182 		offset = res->start;
183 		dev_WARN(&pdev->dev,
184 			 "using legacy dt data for pbias offset\n");
185 	}
186 
187 	cfg.regmap = syscon;
188 	cfg.dev = &pdev->dev;
189 
190 	for (idx = 0; idx < PBIAS_NUM_REGS && count; idx++) {
191 		if (!pbias_matches[idx].init_data ||
192 			!pbias_matches[idx].of_node)
193 			continue;
194 
195 		info = pbias_matches[idx].driver_data;
196 		if (!info)
197 			return -ENODEV;
198 
199 		desc->name = info->name;
200 		desc->owner = THIS_MODULE;
201 		desc->type = REGULATOR_VOLTAGE;
202 		desc->ops = &pbias_regulator_voltage_ops;
203 		desc->volt_table = info->pbias_volt_table;
204 		desc->n_voltages = info->n_voltages;
205 		desc->enable_time = info->enable_time;
206 		desc->vsel_reg = offset;
207 		desc->vsel_mask = info->vmode;
208 		desc->enable_reg = offset;
209 		desc->enable_mask = info->enable_mask;
210 		desc->enable_val = info->enable;
211 		desc->disable_val = info->disable_val;
212 
213 		cfg.init_data = pbias_matches[idx].init_data;
214 		cfg.of_node = pbias_matches[idx].of_node;
215 
216 		rdev = devm_regulator_register(&pdev->dev, desc, &cfg);
217 		if (IS_ERR(rdev)) {
218 			ret = PTR_ERR(rdev);
219 			dev_err(&pdev->dev,
220 				"Failed to register regulator: %d\n", ret);
221 			return ret;
222 		}
223 		desc++;
224 		count--;
225 	}
226 
227 	return 0;
228 }
229 
230 static struct platform_driver pbias_regulator_driver = {
231 	.probe		= pbias_regulator_probe,
232 	.driver		= {
233 		.name		= "pbias-regulator",
234 		.of_match_table = of_match_ptr(pbias_of_match),
235 	},
236 };
237 
238 module_platform_driver(pbias_regulator_driver);
239 
240 MODULE_AUTHOR("Balaji T K <balajitk@ti.com>");
241 MODULE_DESCRIPTION("pbias voltage regulator");
242 MODULE_LICENSE("GPL");
243 MODULE_ALIAS("platform:pbias-regulator");
244