xref: /openbmc/linux/drivers/mfd/as3711.c (revision ac3cb6de)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * AS3711 PMIC MFC driver
4  *
5  * Copyright (C) 2012 Renesas Electronics Corporation
6  * Author: Guennadi Liakhovetski, <g.liakhovetski@gmx.de>
7  */
8 
9 #include <linux/device.h>
10 #include <linux/err.h>
11 #include <linux/i2c.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/mfd/as3711.h>
15 #include <linux/mfd/core.h>
16 #include <linux/of.h>
17 #include <linux/regmap.h>
18 #include <linux/slab.h>
19 
20 enum {
21 	AS3711_REGULATOR,
22 	AS3711_BACKLIGHT,
23 };
24 
25 /*
26  * Ok to have it static: it is only used during probing and multiple I2C devices
27  * cannot be probed simultaneously. Just make sure to avoid stale data.
28  */
29 static struct mfd_cell as3711_subdevs[] = {
30 	[AS3711_REGULATOR] = {.name = "as3711-regulator",},
31 	[AS3711_BACKLIGHT] = {.name = "as3711-backlight",},
32 };
33 
34 static bool as3711_volatile_reg(struct device *dev, unsigned int reg)
35 {
36 	switch (reg) {
37 	case AS3711_GPIO_SIGNAL_IN:
38 	case AS3711_INTERRUPT_STATUS_1:
39 	case AS3711_INTERRUPT_STATUS_2:
40 	case AS3711_INTERRUPT_STATUS_3:
41 	case AS3711_CHARGER_STATUS_1:
42 	case AS3711_CHARGER_STATUS_2:
43 	case AS3711_REG_STATUS:
44 		return true;
45 	}
46 	return false;
47 }
48 
49 static bool as3711_precious_reg(struct device *dev, unsigned int reg)
50 {
51 	switch (reg) {
52 	case AS3711_INTERRUPT_STATUS_1:
53 	case AS3711_INTERRUPT_STATUS_2:
54 	case AS3711_INTERRUPT_STATUS_3:
55 		return true;
56 	}
57 	return false;
58 }
59 
60 static bool as3711_readable_reg(struct device *dev, unsigned int reg)
61 {
62 	switch (reg) {
63 	case AS3711_SD_1_VOLTAGE:
64 	case AS3711_SD_2_VOLTAGE:
65 	case AS3711_SD_3_VOLTAGE:
66 	case AS3711_SD_4_VOLTAGE:
67 	case AS3711_LDO_1_VOLTAGE:
68 	case AS3711_LDO_2_VOLTAGE:
69 	case AS3711_LDO_3_VOLTAGE:
70 	case AS3711_LDO_4_VOLTAGE:
71 	case AS3711_LDO_5_VOLTAGE:
72 	case AS3711_LDO_6_VOLTAGE:
73 	case AS3711_LDO_7_VOLTAGE:
74 	case AS3711_LDO_8_VOLTAGE:
75 	case AS3711_SD_CONTROL:
76 	case AS3711_GPIO_SIGNAL_OUT:
77 	case AS3711_GPIO_SIGNAL_IN:
78 	case AS3711_SD_CONTROL_1:
79 	case AS3711_SD_CONTROL_2:
80 	case AS3711_CURR_CONTROL:
81 	case AS3711_CURR1_VALUE:
82 	case AS3711_CURR2_VALUE:
83 	case AS3711_CURR3_VALUE:
84 	case AS3711_STEPUP_CONTROL_1:
85 	case AS3711_STEPUP_CONTROL_2:
86 	case AS3711_STEPUP_CONTROL_4:
87 	case AS3711_STEPUP_CONTROL_5:
88 	case AS3711_REG_STATUS:
89 	case AS3711_INTERRUPT_STATUS_1:
90 	case AS3711_INTERRUPT_STATUS_2:
91 	case AS3711_INTERRUPT_STATUS_3:
92 	case AS3711_CHARGER_STATUS_1:
93 	case AS3711_CHARGER_STATUS_2:
94 	case AS3711_ASIC_ID_1:
95 	case AS3711_ASIC_ID_2:
96 		return true;
97 	}
98 	return false;
99 }
100 
101 static const struct regmap_config as3711_regmap_config = {
102 	.reg_bits = 8,
103 	.val_bits = 8,
104 	.volatile_reg = as3711_volatile_reg,
105 	.readable_reg = as3711_readable_reg,
106 	.precious_reg = as3711_precious_reg,
107 	.max_register = AS3711_MAX_REG,
108 	.num_reg_defaults_raw = AS3711_NUM_REGS,
109 	.cache_type = REGCACHE_RBTREE,
110 };
111 
112 #ifdef CONFIG_OF
113 static const struct of_device_id as3711_of_match[] = {
114 	{.compatible = "ams,as3711",},
115 	{}
116 };
117 #endif
118 
119 static int as3711_i2c_probe(struct i2c_client *client)
120 {
121 	struct as3711 *as3711;
122 	struct as3711_platform_data *pdata;
123 	unsigned int id1, id2;
124 	int ret;
125 
126 	if (!client->dev.of_node) {
127 		pdata = dev_get_platdata(&client->dev);
128 		if (!pdata)
129 			dev_dbg(&client->dev, "Platform data not found\n");
130 	} else {
131 		pdata = devm_kzalloc(&client->dev,
132 				     sizeof(*pdata), GFP_KERNEL);
133 		if (!pdata)
134 			return -ENOMEM;
135 	}
136 
137 	as3711 = devm_kzalloc(&client->dev, sizeof(struct as3711), GFP_KERNEL);
138 	if (!as3711)
139 		return -ENOMEM;
140 
141 	as3711->dev = &client->dev;
142 	i2c_set_clientdata(client, as3711);
143 
144 	if (client->irq)
145 		dev_notice(&client->dev, "IRQ not supported yet\n");
146 
147 	as3711->regmap = devm_regmap_init_i2c(client, &as3711_regmap_config);
148 	if (IS_ERR(as3711->regmap)) {
149 		ret = PTR_ERR(as3711->regmap);
150 		dev_err(&client->dev,
151 			"regmap initialization failed: %d\n", ret);
152 		return ret;
153 	}
154 
155 	ret = regmap_read(as3711->regmap, AS3711_ASIC_ID_1, &id1);
156 	if (!ret)
157 		ret = regmap_read(as3711->regmap, AS3711_ASIC_ID_2, &id2);
158 	if (ret < 0) {
159 		dev_err(&client->dev, "regmap_read() failed: %d\n", ret);
160 		return ret;
161 	}
162 	if (id1 != 0x8b)
163 		return -ENODEV;
164 	dev_info(as3711->dev, "AS3711 detected: %x:%x\n", id1, id2);
165 
166 	/*
167 	 * We can reuse as3711_subdevs[],
168 	 * it will be copied in mfd_add_devices()
169 	 */
170 	if (pdata) {
171 		as3711_subdevs[AS3711_REGULATOR].platform_data =
172 			&pdata->regulator;
173 		as3711_subdevs[AS3711_REGULATOR].pdata_size =
174 			sizeof(pdata->regulator);
175 		as3711_subdevs[AS3711_BACKLIGHT].platform_data =
176 			&pdata->backlight;
177 		as3711_subdevs[AS3711_BACKLIGHT].pdata_size =
178 			sizeof(pdata->backlight);
179 	} else {
180 		as3711_subdevs[AS3711_REGULATOR].platform_data = NULL;
181 		as3711_subdevs[AS3711_REGULATOR].pdata_size = 0;
182 		as3711_subdevs[AS3711_BACKLIGHT].platform_data = NULL;
183 		as3711_subdevs[AS3711_BACKLIGHT].pdata_size = 0;
184 	}
185 
186 	ret = devm_mfd_add_devices(as3711->dev, -1, as3711_subdevs,
187 				   ARRAY_SIZE(as3711_subdevs), NULL, 0, NULL);
188 	if (ret < 0)
189 		dev_err(&client->dev, "add mfd devices failed: %d\n", ret);
190 
191 	return ret;
192 }
193 
194 static const struct i2c_device_id as3711_i2c_id[] = {
195 	{.name = "as3711", .driver_data = 0},
196 	{}
197 };
198 
199 static struct i2c_driver as3711_i2c_driver = {
200 	.driver = {
201 		   .name = "as3711",
202 		   .of_match_table = of_match_ptr(as3711_of_match),
203 	},
204 	.probe = as3711_i2c_probe,
205 	.id_table = as3711_i2c_id,
206 };
207 
208 static int __init as3711_i2c_init(void)
209 {
210 	return i2c_add_driver(&as3711_i2c_driver);
211 }
212 /* Initialise early */
213 subsys_initcall(as3711_i2c_init);
214