drivers/mfd/88pm80x.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * I2C driver for Marvell 88PM80x
   4  *
   5  * Copyright (C) 2012 Marvell International Ltd.
   6  * Haojian Zhuang <haojian.zhuang@marvell.com>
   7  * Joseph(Yossi) Hanin <yhanin@marvell.com>
   8  * Qiao Zhou <zhouqiao@marvell.com>
   9  */
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/i2c.h>
  13 #include <linux/mfd/88pm80x.h>
  14 #include <linux/slab.h>
  15 #include <linux/uaccess.h>
  16 #include <linux/err.h>
  17
  18 /* 88pm80x chips have same definition for chip id register. */
  19 #define PM80X_CHIP_ID                   (0x00)
  20 #define PM80X_CHIP_ID_NUM(x)            (((x) >> 5) & 0x7)
  21 #define PM80X_CHIP_ID_REVISION(x)       ((x) & 0x1F)
  22
  23 struct pm80x_chip_mapping {
  24         unsigned int    id;
  25         int             type;
  26 };
  27
  28 static struct pm80x_chip_mapping chip_mapping[] = {
  29         /* 88PM800 chip id number */
  30         {0x3,   CHIP_PM800},
  31         /* 88PM805 chip id number */
  32         {0x0,   CHIP_PM805},
  33         /* 88PM860 chip id number */
  34         {0x4,   CHIP_PM860},
  35 };
  36
  37 /*
  38  * workaround: some registers needed by pm805 are defined in pm800, so
  39  * need to use this global variable to maintain the relation between
  40  * pm800 and pm805. would remove it after HW chip fixes the issue.
  41  */
  42 static struct pm80x_chip *g_pm80x_chip;
  43
  44 const struct regmap_config pm80x_regmap_config = {
  45         .reg_bits = 8,
  46         .val_bits = 8,
  47 };
  48 EXPORT_SYMBOL_GPL(pm80x_regmap_config);
  49
  50
  51 int pm80x_init(struct i2c_client *client)
  52 {
  53         struct pm80x_chip *chip;
  54         struct regmap *map;
  55         unsigned int val;
  56         int i, ret = 0;
  57
  58         chip =
  59             devm_kzalloc(&client->dev, sizeof(struct pm80x_chip), GFP_KERNEL);
  60         if (!chip)
  61                 return -ENOMEM;
  62
  63         map = devm_regmap_init_i2c(client, &pm80x_regmap_config);
  64         if (IS_ERR(map)) {
  65                 ret = PTR_ERR(map);
  66                 dev_err(&client->dev, "Failed to allocate register map: %d\n",
  67                         ret);
  68                 return ret;
  69         }
  70
  71         chip->client = client;
  72         chip->regmap = map;
  73
  74         chip->irq = client->irq;
  75
  76         chip->dev = &client->dev;
  77         dev_set_drvdata(chip->dev, chip);
  78         i2c_set_clientdata(chip->client, chip);
  79
  80         ret = regmap_read(chip->regmap, PM80X_CHIP_ID, &val);
  81         if (ret < 0) {
  82                 dev_err(chip->dev, "Failed to read CHIP ID: %d\n", ret);
  83                 return ret;
  84         }
  85
  86         for (i = 0; i < ARRAY_SIZE(chip_mapping); i++) {
  87                 if (chip_mapping[i].id == PM80X_CHIP_ID_NUM(val)) {
  88                         chip->type = chip_mapping[i].type;
  89                         break;
  90                 }
  91         }
  92
  93         if (i == ARRAY_SIZE(chip_mapping)) {
  94                 dev_err(chip->dev,
  95                         "Failed to detect Marvell 88PM800:ChipID[0x%x]\n", val);
  96                 return -EINVAL;
  97         }
  98
  99         device_init_wakeup(&client->dev, 1);
 100
 101         /*
 102          * workaround: set g_pm80x_chip to the first probed chip. if the
 103          * second chip is probed, just point to the companion to each
 104          * other so that pm805 can access those specific register. would
 105          * remove it after HW chip fixes the issue.
 106          */
 107         if (!g_pm80x_chip)
 108                 g_pm80x_chip = chip;
 109         else {
 110                 chip->companion = g_pm80x_chip->client;
 111                 g_pm80x_chip->companion = chip->client;
 112         }
 113
 114         return 0;
 115 }
 116 EXPORT_SYMBOL_GPL(pm80x_init);
 117
 118 int pm80x_deinit(void)
 119 {
 120         /*
 121          * workaround: clear the dependency between pm800 and pm805.
 122          * would remove it after HW chip fixes the issue.
 123          */
 124         if (g_pm80x_chip->companion)
 125                 g_pm80x_chip->companion = NULL;
 126         else
 127                 g_pm80x_chip = NULL;
 128         return 0;
 129 }
 130 EXPORT_SYMBOL_GPL(pm80x_deinit);
 131
 132 #ifdef CONFIG_PM_SLEEP
 133 static int pm80x_suspend(struct device *dev)
 134 {
 135         struct i2c_client *client = to_i2c_client(dev);
 136         struct pm80x_chip *chip = i2c_get_clientdata(client);
 137
 138         if (chip && chip->wu_flag)
 139                 if (device_may_wakeup(chip->dev))
 140                         enable_irq_wake(chip->irq);
 141
 142         return 0;
 143 }
 144
 145 static int pm80x_resume(struct device *dev)
 146 {
 147         struct i2c_client *client = to_i2c_client(dev);
 148         struct pm80x_chip *chip = i2c_get_clientdata(client);
 149
 150         if (chip && chip->wu_flag)
 151                 if (device_may_wakeup(chip->dev))
 152                         disable_irq_wake(chip->irq);
 153
 154         return 0;
 155 }
 156 #endif
 157
 158 SIMPLE_DEV_PM_OPS(pm80x_pm_ops, pm80x_suspend, pm80x_resume);
 159 EXPORT_SYMBOL_GPL(pm80x_pm_ops);
 160
 161 MODULE_DESCRIPTION("I2C Driver for Marvell 88PM80x");
 162 MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
 163 MODULE_LICENSE("GPL");