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         i2c_set_clientdata(chip->client, chip);
  78
  79         ret = regmap_read(chip->regmap, PM80X_CHIP_ID, &val);
  80         if (ret < 0) {
  81                 dev_err(chip->dev, "Failed to read CHIP ID: %d\n", ret);
  82                 return ret;
  83         }
  84
  85         for (i = 0; i < ARRAY_SIZE(chip_mapping); i++) {
  86                 if (chip_mapping[i].id == PM80X_CHIP_ID_NUM(val)) {
  87                         chip->type = chip_mapping[i].type;
  88                         break;
  89                 }
  90         }
  91
  92         if (i == ARRAY_SIZE(chip_mapping)) {
  93                 dev_err(chip->dev,
  94                         "Failed to detect Marvell 88PM800:ChipID[0x%x]\n", val);
  95                 return -EINVAL;
  96         }
  97
  98         device_init_wakeup(&client->dev, 1);
  99
 100         /*
 101          * workaround: set g_pm80x_chip to the first probed chip. if the
 102          * second chip is probed, just point to the companion to each
 103          * other so that pm805 can access those specific register. would
 104          * remove it after HW chip fixes the issue.
 105          */
 106         if (!g_pm80x_chip)
 107                 g_pm80x_chip = chip;
 108         else {
 109                 chip->companion = g_pm80x_chip->client;
 110                 g_pm80x_chip->companion = chip->client;
 111         }
 112
 113         return 0;
 114 }
 115 EXPORT_SYMBOL_GPL(pm80x_init);
 116
 117 int pm80x_deinit(void)
 118 {
 119         /*
 120          * workaround: clear the dependency between pm800 and pm805.
 121          * would remove it after HW chip fixes the issue.
 122          */
 123         if (g_pm80x_chip->companion)
 124                 g_pm80x_chip->companion = NULL;
 125         else
 126                 g_pm80x_chip = NULL;
 127         return 0;
 128 }
 129 EXPORT_SYMBOL_GPL(pm80x_deinit);
 130
 131 static int pm80x_suspend(struct device *dev)
 132 {
 133         struct i2c_client *client = to_i2c_client(dev);
 134         struct pm80x_chip *chip = i2c_get_clientdata(client);
 135
 136         if (chip && chip->wu_flag)
 137                 if (device_may_wakeup(chip->dev))
 138                         enable_irq_wake(chip->irq);
 139
 140         return 0;
 141 }
 142
 143 static int pm80x_resume(struct device *dev)
 144 {
 145         struct i2c_client *client = to_i2c_client(dev);
 146         struct pm80x_chip *chip = i2c_get_clientdata(client);
 147
 148         if (chip && chip->wu_flag)
 149                 if (device_may_wakeup(chip->dev))
 150                         disable_irq_wake(chip->irq);
 151
 152         return 0;
 153 }
 154
 155 EXPORT_GPL_SIMPLE_DEV_PM_OPS(pm80x_pm_ops, pm80x_suspend, pm80x_resume);
 156
 157 MODULE_DESCRIPTION("I2C Driver for Marvell 88PM80x");
 158 MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
 159 MODULE_LICENSE("GPL");