xref: /openbmc/linux/drivers/mfd/as3711.c (revision f35e839a)
1 /*
2  * AS3711 PMIC MFC driver
3  *
4  * Copyright (C) 2012 Renesas Electronics Corporation
5  * Author: Guennadi Liakhovetski, <g.liakhovetski@gmx.de>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the version 2 of the GNU General Public License as
9  * published by the Free Software Foundation
10  */
11 
12 #include <linux/device.h>
13 #include <linux/err.h>
14 #include <linux/i2c.h>
15 #include <linux/init.h>
16 #include <linux/kernel.h>
17 #include <linux/mfd/as3711.h>
18 #include <linux/mfd/core.h>
19 #include <linux/module.h>
20 #include <linux/regmap.h>
21 #include <linux/slab.h>
22 
23 enum {
24 	AS3711_REGULATOR,
25 	AS3711_BACKLIGHT,
26 };
27 
28 /*
29  * Ok to have it static: it is only used during probing and multiple I2C devices
30  * cannot be probed simultaneously. Just make sure to avoid stale data.
31  */
32 static struct mfd_cell as3711_subdevs[] = {
33 	[AS3711_REGULATOR] = {.name = "as3711-regulator",},
34 	[AS3711_BACKLIGHT] = {.name = "as3711-backlight",},
35 };
36 
37 static bool as3711_volatile_reg(struct device *dev, unsigned int reg)
38 {
39 	switch (reg) {
40 	case AS3711_GPIO_SIGNAL_IN:
41 	case AS3711_INTERRUPT_STATUS_1:
42 	case AS3711_INTERRUPT_STATUS_2:
43 	case AS3711_INTERRUPT_STATUS_3:
44 	case AS3711_CHARGER_STATUS_1:
45 	case AS3711_CHARGER_STATUS_2:
46 	case AS3711_REG_STATUS:
47 		return true;
48 	}
49 	return false;
50 }
51 
52 static bool as3711_precious_reg(struct device *dev, unsigned int reg)
53 {
54 	switch (reg) {
55 	case AS3711_INTERRUPT_STATUS_1:
56 	case AS3711_INTERRUPT_STATUS_2:
57 	case AS3711_INTERRUPT_STATUS_3:
58 		return true;
59 	}
60 	return false;
61 }
62 
63 static bool as3711_readable_reg(struct device *dev, unsigned int reg)
64 {
65 	switch (reg) {
66 	case AS3711_SD_1_VOLTAGE:
67 	case AS3711_SD_2_VOLTAGE:
68 	case AS3711_SD_3_VOLTAGE:
69 	case AS3711_SD_4_VOLTAGE:
70 	case AS3711_LDO_1_VOLTAGE:
71 	case AS3711_LDO_2_VOLTAGE:
72 	case AS3711_LDO_3_VOLTAGE:
73 	case AS3711_LDO_4_VOLTAGE:
74 	case AS3711_LDO_5_VOLTAGE:
75 	case AS3711_LDO_6_VOLTAGE:
76 	case AS3711_LDO_7_VOLTAGE:
77 	case AS3711_LDO_8_VOLTAGE:
78 	case AS3711_SD_CONTROL:
79 	case AS3711_GPIO_SIGNAL_OUT:
80 	case AS3711_GPIO_SIGNAL_IN:
81 	case AS3711_SD_CONTROL_1:
82 	case AS3711_SD_CONTROL_2:
83 	case AS3711_CURR_CONTROL:
84 	case AS3711_CURR1_VALUE:
85 	case AS3711_CURR2_VALUE:
86 	case AS3711_CURR3_VALUE:
87 	case AS3711_STEPUP_CONTROL_1:
88 	case AS3711_STEPUP_CONTROL_2:
89 	case AS3711_STEPUP_CONTROL_4:
90 	case AS3711_STEPUP_CONTROL_5:
91 	case AS3711_REG_STATUS:
92 	case AS3711_INTERRUPT_STATUS_1:
93 	case AS3711_INTERRUPT_STATUS_2:
94 	case AS3711_INTERRUPT_STATUS_3:
95 	case AS3711_CHARGER_STATUS_1:
96 	case AS3711_CHARGER_STATUS_2:
97 	case AS3711_ASIC_ID_1:
98 	case AS3711_ASIC_ID_2:
99 		return true;
100 	}
101 	return false;
102 }
103 
104 static const struct regmap_config as3711_regmap_config = {
105 	.reg_bits = 8,
106 	.val_bits = 8,
107 	.volatile_reg = as3711_volatile_reg,
108 	.readable_reg = as3711_readable_reg,
109 	.precious_reg = as3711_precious_reg,
110 	.max_register = AS3711_MAX_REGS,
111 	.num_reg_defaults_raw = AS3711_MAX_REGS,
112 	.cache_type = REGCACHE_RBTREE,
113 };
114 
115 #ifdef CONFIG_OF
116 static struct of_device_id as3711_of_match[] = {
117 	{.compatible = "ams,as3711",},
118 	{}
119 };
120 MODULE_DEVICE_TABLE(of, as3711_of_match);
121 #endif
122 
123 static int as3711_i2c_probe(struct i2c_client *client,
124 			    const struct i2c_device_id *id)
125 {
126 	struct as3711 *as3711;
127 	struct as3711_platform_data *pdata;
128 	unsigned int id1, id2;
129 	int ret;
130 
131 	if (!client->dev.of_node) {
132 		pdata = client->dev.platform_data;
133 		if (!pdata)
134 			dev_dbg(&client->dev, "Platform data not found\n");
135 	} else {
136 		pdata = devm_kzalloc(&client->dev,
137 				     sizeof(*pdata), GFP_KERNEL);
138 		if (!pdata) {
139 			dev_err(&client->dev, "Failed to allocate pdata\n");
140 			return -ENOMEM;
141 		}
142 	}
143 
144 	as3711 = devm_kzalloc(&client->dev, sizeof(struct as3711), GFP_KERNEL);
145 	if (!as3711) {
146 		dev_err(&client->dev, "Memory allocation failed\n");
147 		return -ENOMEM;
148 	}
149 
150 	as3711->dev = &client->dev;
151 	i2c_set_clientdata(client, as3711);
152 
153 	if (client->irq)
154 		dev_notice(&client->dev, "IRQ not supported yet\n");
155 
156 	as3711->regmap = devm_regmap_init_i2c(client, &as3711_regmap_config);
157 	if (IS_ERR(as3711->regmap)) {
158 		ret = PTR_ERR(as3711->regmap);
159 		dev_err(&client->dev, "regmap initialization failed: %d\n", ret);
160 		return ret;
161 	}
162 
163 	ret = regmap_read(as3711->regmap, AS3711_ASIC_ID_1, &id1);
164 	if (!ret)
165 		ret = regmap_read(as3711->regmap, AS3711_ASIC_ID_2, &id2);
166 	if (ret < 0) {
167 		dev_err(&client->dev, "regmap_read() failed: %d\n", ret);
168 		return ret;
169 	}
170 	if (id1 != 0x8b)
171 		return -ENODEV;
172 	dev_info(as3711->dev, "AS3711 detected: %x:%x\n", id1, id2);
173 
174 	/* We can reuse as3711_subdevs[], it will be copied in mfd_add_devices() */
175 	if (pdata) {
176 		as3711_subdevs[AS3711_REGULATOR].platform_data = &pdata->regulator;
177 		as3711_subdevs[AS3711_REGULATOR].pdata_size = sizeof(pdata->regulator);
178 		as3711_subdevs[AS3711_BACKLIGHT].platform_data = &pdata->backlight;
179 		as3711_subdevs[AS3711_BACKLIGHT].pdata_size = sizeof(pdata->backlight);
180 	} else {
181 		as3711_subdevs[AS3711_REGULATOR].platform_data = NULL;
182 		as3711_subdevs[AS3711_REGULATOR].pdata_size = 0;
183 		as3711_subdevs[AS3711_BACKLIGHT].platform_data = NULL;
184 		as3711_subdevs[AS3711_BACKLIGHT].pdata_size = 0;
185 	}
186 
187 	ret = mfd_add_devices(as3711->dev, -1, as3711_subdevs,
188 			      ARRAY_SIZE(as3711_subdevs), NULL, 0, NULL);
189 	if (ret < 0)
190 		dev_err(&client->dev, "add mfd devices failed: %d\n", ret);
191 
192 	return ret;
193 }
194 
195 static int as3711_i2c_remove(struct i2c_client *client)
196 {
197 	struct as3711 *as3711 = i2c_get_clientdata(client);
198 
199 	mfd_remove_devices(as3711->dev);
200 	return 0;
201 }
202 
203 static const struct i2c_device_id as3711_i2c_id[] = {
204 	{.name = "as3711", .driver_data = 0},
205 	{}
206 };
207 
208 MODULE_DEVICE_TABLE(i2c, as3711_i2c_id);
209 
210 static struct i2c_driver as3711_i2c_driver = {
211 	.driver = {
212 		   .name = "as3711",
213 		   .owner = THIS_MODULE,
214 		   .of_match_table = of_match_ptr(as3711_of_match),
215 	},
216 	.probe = as3711_i2c_probe,
217 	.remove = as3711_i2c_remove,
218 	.id_table = as3711_i2c_id,
219 };
220 
221 static int __init as3711_i2c_init(void)
222 {
223 	return i2c_add_driver(&as3711_i2c_driver);
224 }
225 /* Initialise early */
226 subsys_initcall(as3711_i2c_init);
227 
228 static void __exit as3711_i2c_exit(void)
229 {
230 	i2c_del_driver(&as3711_i2c_driver);
231 }
232 module_exit(as3711_i2c_exit);
233 
234 MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
235 MODULE_DESCRIPTION("AS3711 PMIC driver");
236 MODULE_LICENSE("GPL v2");
237