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/of.h>
21#include <linux/regmap.h>
22#include <linux/slab.h>
23
24enum {
25	AS3711_REGULATOR,
26	AS3711_BACKLIGHT,
27};
28
29/*
30 * Ok to have it static: it is only used during probing and multiple I2C devices
31 * cannot be probed simultaneously. Just make sure to avoid stale data.
32 */
33static struct mfd_cell as3711_subdevs[] = {
34	[AS3711_REGULATOR] = {.name = "as3711-regulator",},
35	[AS3711_BACKLIGHT] = {.name = "as3711-backlight",},
36};
37
38static bool as3711_volatile_reg(struct device *dev, unsigned int reg)
39{
40	switch (reg) {
41	case AS3711_GPIO_SIGNAL_IN:
42	case AS3711_INTERRUPT_STATUS_1:
43	case AS3711_INTERRUPT_STATUS_2:
44	case AS3711_INTERRUPT_STATUS_3:
45	case AS3711_CHARGER_STATUS_1:
46	case AS3711_CHARGER_STATUS_2:
47	case AS3711_REG_STATUS:
48		return true;
49	}
50	return false;
51}
52
53static bool as3711_precious_reg(struct device *dev, unsigned int reg)
54{
55	switch (reg) {
56	case AS3711_INTERRUPT_STATUS_1:
57	case AS3711_INTERRUPT_STATUS_2:
58	case AS3711_INTERRUPT_STATUS_3:
59		return true;
60	}
61	return false;
62}
63
64static bool as3711_readable_reg(struct device *dev, unsigned int reg)
65{
66	switch (reg) {
67	case AS3711_SD_1_VOLTAGE:
68	case AS3711_SD_2_VOLTAGE:
69	case AS3711_SD_3_VOLTAGE:
70	case AS3711_SD_4_VOLTAGE:
71	case AS3711_LDO_1_VOLTAGE:
72	case AS3711_LDO_2_VOLTAGE:
73	case AS3711_LDO_3_VOLTAGE:
74	case AS3711_LDO_4_VOLTAGE:
75	case AS3711_LDO_5_VOLTAGE:
76	case AS3711_LDO_6_VOLTAGE:
77	case AS3711_LDO_7_VOLTAGE:
78	case AS3711_LDO_8_VOLTAGE:
79	case AS3711_SD_CONTROL:
80	case AS3711_GPIO_SIGNAL_OUT:
81	case AS3711_GPIO_SIGNAL_IN:
82	case AS3711_SD_CONTROL_1:
83	case AS3711_SD_CONTROL_2:
84	case AS3711_CURR_CONTROL:
85	case AS3711_CURR1_VALUE:
86	case AS3711_CURR2_VALUE:
87	case AS3711_CURR3_VALUE:
88	case AS3711_STEPUP_CONTROL_1:
89	case AS3711_STEPUP_CONTROL_2:
90	case AS3711_STEPUP_CONTROL_4:
91	case AS3711_STEPUP_CONTROL_5:
92	case AS3711_REG_STATUS:
93	case AS3711_INTERRUPT_STATUS_1:
94	case AS3711_INTERRUPT_STATUS_2:
95	case AS3711_INTERRUPT_STATUS_3:
96	case AS3711_CHARGER_STATUS_1:
97	case AS3711_CHARGER_STATUS_2:
98	case AS3711_ASIC_ID_1:
99	case AS3711_ASIC_ID_2:
100		return true;
101	}
102	return false;
103}
104
105static const struct regmap_config as3711_regmap_config = {
106	.reg_bits = 8,
107	.val_bits = 8,
108	.volatile_reg = as3711_volatile_reg,
109	.readable_reg = as3711_readable_reg,
110	.precious_reg = as3711_precious_reg,
111	.max_register = AS3711_MAX_REGS,
112	.num_reg_defaults_raw = AS3711_MAX_REGS,
113	.cache_type = REGCACHE_RBTREE,
114};
115
116#ifdef CONFIG_OF
117static const struct of_device_id as3711_of_match[] = {
118	{.compatible = "ams,as3711",},
119	{}
120};
121MODULE_DEVICE_TABLE(of, as3711_of_match);
122#endif
123
124static int as3711_i2c_probe(struct i2c_client *client,
125			    const struct i2c_device_id *id)
126{
127	struct as3711 *as3711;
128	struct as3711_platform_data *pdata;
129	unsigned int id1, id2;
130	int ret;
131
132	if (!client->dev.of_node) {
133		pdata = dev_get_platdata(&client->dev);
134		if (!pdata)
135			dev_dbg(&client->dev, "Platform data not found\n");
136	} else {
137		pdata = devm_kzalloc(&client->dev,
138				     sizeof(*pdata), GFP_KERNEL);
139		if (!pdata) {
140			dev_err(&client->dev, "Failed to allocate pdata\n");
141			return -ENOMEM;
142		}
143	}
144
145	as3711 = devm_kzalloc(&client->dev, sizeof(struct as3711), GFP_KERNEL);
146	if (!as3711) {
147		dev_err(&client->dev, "Memory allocation failed\n");
148		return -ENOMEM;
149	}
150
151	as3711->dev = &client->dev;
152	i2c_set_clientdata(client, as3711);
153
154	if (client->irq)
155		dev_notice(&client->dev, "IRQ not supported yet\n");
156
157	as3711->regmap = devm_regmap_init_i2c(client, &as3711_regmap_config);
158	if (IS_ERR(as3711->regmap)) {
159		ret = PTR_ERR(as3711->regmap);
160		dev_err(&client->dev, "regmap initialization failed: %d\n", ret);
161		return ret;
162	}
163
164	ret = regmap_read(as3711->regmap, AS3711_ASIC_ID_1, &id1);
165	if (!ret)
166		ret = regmap_read(as3711->regmap, AS3711_ASIC_ID_2, &id2);
167	if (ret < 0) {
168		dev_err(&client->dev, "regmap_read() failed: %d\n", ret);
169		return ret;
170	}
171	if (id1 != 0x8b)
172		return -ENODEV;
173	dev_info(as3711->dev, "AS3711 detected: %x:%x\n", id1, id2);
174
175	/* We can reuse as3711_subdevs[], it will be copied in mfd_add_devices() */
176	if (pdata) {
177		as3711_subdevs[AS3711_REGULATOR].platform_data = &pdata->regulator;
178		as3711_subdevs[AS3711_REGULATOR].pdata_size = sizeof(pdata->regulator);
179		as3711_subdevs[AS3711_BACKLIGHT].platform_data = &pdata->backlight;
180		as3711_subdevs[AS3711_BACKLIGHT].pdata_size = sizeof(pdata->backlight);
181	} else {
182		as3711_subdevs[AS3711_REGULATOR].platform_data = NULL;
183		as3711_subdevs[AS3711_REGULATOR].pdata_size = 0;
184		as3711_subdevs[AS3711_BACKLIGHT].platform_data = NULL;
185		as3711_subdevs[AS3711_BACKLIGHT].pdata_size = 0;
186	}
187
188	ret = mfd_add_devices(as3711->dev, -1, as3711_subdevs,
189			      ARRAY_SIZE(as3711_subdevs), NULL, 0, NULL);
190	if (ret < 0)
191		dev_err(&client->dev, "add mfd devices failed: %d\n", ret);
192
193	return ret;
194}
195
196static int as3711_i2c_remove(struct i2c_client *client)
197{
198	struct as3711 *as3711 = i2c_get_clientdata(client);
199
200	mfd_remove_devices(as3711->dev);
201	return 0;
202}
203
204static const struct i2c_device_id as3711_i2c_id[] = {
205	{.name = "as3711", .driver_data = 0},
206	{}
207};
208
209MODULE_DEVICE_TABLE(i2c, as3711_i2c_id);
210
211static struct i2c_driver as3711_i2c_driver = {
212	.driver = {
213		   .name = "as3711",
214		   .owner = THIS_MODULE,
215		   .of_match_table = of_match_ptr(as3711_of_match),
216	},
217	.probe = as3711_i2c_probe,
218	.remove = as3711_i2c_remove,
219	.id_table = as3711_i2c_id,
220};
221
222static int __init as3711_i2c_init(void)
223{
224	return i2c_add_driver(&as3711_i2c_driver);
225}
226/* Initialise early */
227subsys_initcall(as3711_i2c_init);
228
229static void __exit as3711_i2c_exit(void)
230{
231	i2c_del_driver(&as3711_i2c_driver);
232}
233module_exit(as3711_i2c_exit);
234
235MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
236MODULE_DESCRIPTION("AS3711 PMIC driver");
237MODULE_LICENSE("GPL v2");
238