drivers/mfd/88pm80x.c

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