1 /*
2  * pbias-regulator.c
3  *
4  * Copyright (C) 2014 Texas Instruments Incorporated - http://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 };
38 
39 struct pbias_regulator_data {
40 	struct regulator_desc desc;
41 	void __iomem *pbias_addr;
42 	struct regulator_dev *dev;
43 	struct regmap *syscon;
44 	const struct pbias_reg_info *info;
45 	int voltage;
46 };
47 
48 struct pbias_of_data {
49 	unsigned int offset;
50 };
51 
52 static const unsigned int pbias_volt_table[] = {
53 	1800000,
54 	3000000
55 };
56 
57 static const struct regulator_ops pbias_regulator_voltage_ops = {
58 	.list_voltage = regulator_list_voltage_table,
59 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
60 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
61 	.enable = regulator_enable_regmap,
62 	.disable = regulator_disable_regmap,
63 	.is_enabled = regulator_is_enabled_regmap,
64 };
65 
66 static const struct pbias_reg_info pbias_mmc_omap2430 = {
67 	.enable = BIT(1),
68 	.enable_mask = BIT(1),
69 	.vmode = BIT(0),
70 	.disable_val = 0,
71 	.enable_time = 100,
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 	.name = "pbias_sim_omap3"
81 };
82 
83 static const struct pbias_reg_info pbias_mmc_omap4 = {
84 	.enable = BIT(26) | BIT(22),
85 	.enable_mask = BIT(26) | BIT(25) | BIT(22),
86 	.disable_val = BIT(25),
87 	.vmode = BIT(21),
88 	.enable_time = 100,
89 	.name = "pbias_mmc_omap4"
90 };
91 
92 static const struct pbias_reg_info pbias_mmc_omap5 = {
93 	.enable = BIT(27) | BIT(26),
94 	.enable_mask = BIT(27) | BIT(25) | BIT(26),
95 	.disable_val = BIT(25),
96 	.vmode = BIT(21),
97 	.enable_time = 100,
98 	.name = "pbias_mmc_omap5"
99 };
100 
101 static struct of_regulator_match pbias_matches[] = {
102 	{ .name = "pbias_mmc_omap2430", .driver_data = (void *)&pbias_mmc_omap2430},
103 	{ .name = "pbias_sim_omap3", .driver_data = (void *)&pbias_sim_omap3},
104 	{ .name = "pbias_mmc_omap4", .driver_data = (void *)&pbias_mmc_omap4},
105 	{ .name = "pbias_mmc_omap5", .driver_data = (void *)&pbias_mmc_omap5},
106 };
107 #define PBIAS_NUM_REGS	ARRAY_SIZE(pbias_matches)
108 
109 /* Offset from SCM general area (and syscon) base */
110 
111 static const struct pbias_of_data pbias_of_data_omap2 = {
112 	.offset = 0x230,
113 };
114 
115 static const struct pbias_of_data pbias_of_data_omap3 = {
116 	.offset = 0x2b0,
117 };
118 
119 static const struct pbias_of_data pbias_of_data_omap4 = {
120 	.offset = 0x60,
121 };
122 
123 static const struct pbias_of_data pbias_of_data_omap5 = {
124 	.offset = 0x60,
125 };
126 
127 static const struct pbias_of_data pbias_of_data_dra7 = {
128 	.offset = 0xe00,
129 };
130 
131 static const struct of_device_id pbias_of_match[] = {
132 	{ .compatible = "ti,pbias-omap", },
133 	{ .compatible = "ti,pbias-omap2", .data = &pbias_of_data_omap2, },
134 	{ .compatible = "ti,pbias-omap3", .data = &pbias_of_data_omap3, },
135 	{ .compatible = "ti,pbias-omap4", .data = &pbias_of_data_omap4, },
136 	{ .compatible = "ti,pbias-omap5", .data = &pbias_of_data_omap5, },
137 	{ .compatible = "ti,pbias-dra7", .data = &pbias_of_data_dra7, },
138 	{},
139 };
140 MODULE_DEVICE_TABLE(of, pbias_of_match);
141 
142 static int pbias_regulator_probe(struct platform_device *pdev)
143 {
144 	struct device_node *np = pdev->dev.of_node;
145 	struct pbias_regulator_data *drvdata;
146 	struct resource *res;
147 	struct regulator_config cfg = { };
148 	struct regmap *syscon;
149 	const struct pbias_reg_info *info;
150 	int ret = 0;
151 	int count, idx, data_idx = 0;
152 	const struct of_device_id *match;
153 	const struct pbias_of_data *data;
154 	unsigned int offset;
155 
156 	count = of_regulator_match(&pdev->dev, np, pbias_matches,
157 						PBIAS_NUM_REGS);
158 	if (count < 0)
159 		return count;
160 
161 	drvdata = devm_kzalloc(&pdev->dev, sizeof(struct pbias_regulator_data)
162 			       * count, GFP_KERNEL);
163 	if (!drvdata)
164 		return -ENOMEM;
165 
166 	syscon = syscon_regmap_lookup_by_phandle(np, "syscon");
167 	if (IS_ERR(syscon))
168 		return PTR_ERR(syscon);
169 
170 	match = of_match_device(of_match_ptr(pbias_of_match), &pdev->dev);
171 	if (match && match->data) {
172 		data = match->data;
173 		offset = data->offset;
174 	} else {
175 		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
176 		if (!res)
177 			return -EINVAL;
178 
179 		offset = res->start;
180 		dev_WARN(&pdev->dev,
181 			 "using legacy dt data for pbias offset\n");
182 	}
183 
184 	cfg.regmap = syscon;
185 	cfg.dev = &pdev->dev;
186 
187 	for (idx = 0; idx < PBIAS_NUM_REGS && data_idx < count; idx++) {
188 		if (!pbias_matches[idx].init_data ||
189 			!pbias_matches[idx].of_node)
190 			continue;
191 
192 		info = pbias_matches[idx].driver_data;
193 		if (!info)
194 			return -ENODEV;
195 
196 		drvdata[data_idx].syscon = syscon;
197 		drvdata[data_idx].info = info;
198 		drvdata[data_idx].desc.name = info->name;
199 		drvdata[data_idx].desc.owner = THIS_MODULE;
200 		drvdata[data_idx].desc.type = REGULATOR_VOLTAGE;
201 		drvdata[data_idx].desc.ops = &pbias_regulator_voltage_ops;
202 		drvdata[data_idx].desc.volt_table = pbias_volt_table;
203 		drvdata[data_idx].desc.n_voltages = 2;
204 		drvdata[data_idx].desc.enable_time = info->enable_time;
205 		drvdata[data_idx].desc.vsel_reg = offset;
206 		drvdata[data_idx].desc.vsel_mask = info->vmode;
207 		drvdata[data_idx].desc.enable_reg = offset;
208 		drvdata[data_idx].desc.enable_mask = info->enable_mask;
209 		drvdata[data_idx].desc.enable_val = info->enable;
210 		drvdata[data_idx].desc.disable_val = info->disable_val;
211 
212 		cfg.init_data = pbias_matches[idx].init_data;
213 		cfg.driver_data = &drvdata[data_idx];
214 		cfg.of_node = pbias_matches[idx].of_node;
215 
216 		drvdata[data_idx].dev = devm_regulator_register(&pdev->dev,
217 					&drvdata[data_idx].desc, &cfg);
218 		if (IS_ERR(drvdata[data_idx].dev)) {
219 			ret = PTR_ERR(drvdata[data_idx].dev);
220 			dev_err(&pdev->dev,
221 				"Failed to register regulator: %d\n", ret);
222 			goto err_regulator;
223 		}
224 		data_idx++;
225 	}
226 
227 	platform_set_drvdata(pdev, drvdata);
228 
229 err_regulator:
230 	return ret;
231 }
232 
233 static struct platform_driver pbias_regulator_driver = {
234 	.probe		= pbias_regulator_probe,
235 	.driver		= {
236 		.name		= "pbias-regulator",
237 		.of_match_table = of_match_ptr(pbias_of_match),
238 	},
239 };
240 
241 module_platform_driver(pbias_regulator_driver);
242 
243 MODULE_AUTHOR("Balaji T K <balajitk@ti.com>");
244 MODULE_DESCRIPTION("pbias voltage regulator");
245 MODULE_LICENSE("GPL");
246 MODULE_ALIAS("platform:pbias-regulator");
247