drivers/mfd/tps68470.c

   1 /*
   2  * TPS68470 chip Parent driver
   3  *
   4  * Copyright (C) 2017 Intel Corporation
   5  *
   6  * Authors:
   7  *      Rajmohan Mani <rajmohan.mani@intel.com>
   8  *      Tianshu Qiu <tian.shu.qiu@intel.com>
   9  *      Jian Xu Zheng <jian.xu.zheng@intel.com>
  10  *      Yuning Pu <yuning.pu@intel.com>
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License as
  14  * published by the Free Software Foundation version 2.
  15  *
  16  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
  17  * kind, whether express or implied; without even the implied warranty
  18  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  */
  21
  22 #include <linux/acpi.h>
  23 #include <linux/delay.h>
  24 #include <linux/i2c.h>
  25 #include <linux/init.h>
  26 #include <linux/mfd/core.h>
  27 #include <linux/mfd/tps68470.h>
  28 #include <linux/regmap.h>
  29
  30 static const struct mfd_cell tps68470s[] = {
  31         { .name = "tps68470-gpio" },
  32         { .name = "tps68470_pmic_opregion" },
  33 };
  34
  35 static const struct regmap_config tps68470_regmap_config = {
  36         .reg_bits = 8,
  37         .val_bits = 8,
  38         .max_register = TPS68470_REG_MAX,
  39 };
  40
  41 static int tps68470_chip_init(struct device *dev, struct regmap *regmap)
  42 {
  43         unsigned int version;
  44         int ret;
  45
  46         /* Force software reset */
  47         ret = regmap_write(regmap, TPS68470_REG_RESET, TPS68470_REG_RESET_MASK);
  48         if (ret)
  49                 return ret;
  50
  51         ret = regmap_read(regmap, TPS68470_REG_REVID, &version);
  52         if (ret) {
  53                 dev_err(dev, "Failed to read revision register: %d\n", ret);
  54                 return ret;
  55         }
  56
  57         dev_info(dev, "TPS68470 REVID: 0x%x\n", version);
  58
  59         return 0;
  60 }
  61
  62 static int tps68470_probe(struct i2c_client *client)
  63 {
  64         struct device *dev = &client->dev;
  65         struct regmap *regmap;
  66         int ret;
  67
  68         regmap = devm_regmap_init_i2c(client, &tps68470_regmap_config);
  69         if (IS_ERR(regmap)) {
  70                 dev_err(dev, "devm_regmap_init_i2c Error %ld\n",
  71                         PTR_ERR(regmap));
  72                 return PTR_ERR(regmap);
  73         }
  74
  75         i2c_set_clientdata(client, regmap);
  76
  77         ret = tps68470_chip_init(dev, regmap);
  78         if (ret < 0) {
  79                 dev_err(dev, "TPS68470 Init Error %d\n", ret);
  80                 return ret;
  81         }
  82
  83         ret = devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE, tps68470s,
  84                               ARRAY_SIZE(tps68470s), NULL, 0, NULL);
  85         if (ret < 0) {
  86                 dev_err(dev, "devm_mfd_add_devices failed: %d\n", ret);
  87                 return ret;
  88         }
  89
  90         return 0;
  91 }
  92
  93 static const struct acpi_device_id tps68470_acpi_ids[] = {
  94         {"INT3472"},
  95         {},
  96 };
  97 MODULE_DEVICE_TABLE(acpi, tps68470_acpi_ids);
  98
  99 static struct i2c_driver tps68470_driver = {
 100         .driver = {
 101                    .name = "tps68470",
 102                    .acpi_match_table = tps68470_acpi_ids,
 103         },
 104         .probe_new = tps68470_probe,
 105 };
 106 builtin_i2c_driver(tps68470_driver);