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
 20enum {
 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 */
 29static struct mfd_cell as3711_subdevs[] = {
 30	[AS3711_REGULATOR] = {.name = "as3711-regulator",},
 31	[AS3711_BACKLIGHT] = {.name = "as3711-backlight",},
 32};
 33
 34static 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
 49static 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
 60static 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
101static 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
113static const struct of_device_id as3711_of_match[] = {
114	{.compatible = "ams,as3711",},
115	{}
116};
117#endif
118
119static 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
194static const struct i2c_device_id as3711_i2c_id[] = {
195	{.name = "as3711", .driver_data = 0},
196	{}
197};
198
199static struct i2c_driver as3711_i2c_driver = {
200	.driver = {
201		   .name = "as3711",
202		   .of_match_table = of_match_ptr(as3711_of_match),
203	},
204	.probe_new = as3711_i2c_probe,
205	.id_table = as3711_i2c_id,
206};
207
208static int __init as3711_i2c_init(void)
209{
210	return i2c_add_driver(&as3711_i2c_driver);
211}
212/* Initialise early */
213subsys_initcall(as3711_i2c_init);