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 };
  37
  38 /*
  39  * workaround: some registers needed by pm805 are defined in pm800, so
  40  * need to use this global variable to maintain the relation between
  41  * pm800 and pm805. would remove it after HW chip fixes the issue.
  42  */
  43 static struct pm80x_chip *g_pm80x_chip;
  44
  45 const struct regmap_config pm80x_regmap_config = {
  46         .reg_bits = 8,
  47         .val_bits = 8,
  48 };
  49 EXPORT_SYMBOL_GPL(pm80x_regmap_config);
  50
  51
  52 int pm80x_init(struct i2c_client *client)
  53 {
  54         struct pm80x_chip *chip;
  55         struct regmap *map;
  56         unsigned int val;
  57         int i, ret = 0;
  58
  59         chip =
  60             devm_kzalloc(&client->dev, sizeof(struct pm80x_chip), GFP_KERNEL);
  61         if (!chip)
  62                 return -ENOMEM;
  63
  64         map = devm_regmap_init_i2c(client, &pm80x_regmap_config);
  65         if (IS_ERR(map)) {
  66                 ret = PTR_ERR(map);
  67                 dev_err(&client->dev, "Failed to allocate register map: %d\n",
  68                         ret);
  69                 return ret;
  70         }
  71
  72         chip->client = client;
  73         chip->regmap = map;
  74
  75         chip->irq = client->irq;
  76
  77         chip->dev = &client->dev;
  78         dev_set_drvdata(chip->dev, chip);
  79         i2c_set_clientdata(chip->client, chip);
  80
  81         ret = regmap_read(chip->regmap, PM80X_CHIP_ID, &val);
  82         if (ret < 0) {
  83                 dev_err(chip->dev, "Failed to read CHIP ID: %d\n", ret);
  84                 return ret;
  85         }
  86
  87         for (i = 0; i < ARRAY_SIZE(chip_mapping); i++) {
  88                 if (chip_mapping[i].id == PM80X_CHIP_ID_NUM(val)) {
  89                         chip->type = chip_mapping[i].type;
  90                         break;
  91                 }
  92         }
  93
  94         if (i == ARRAY_SIZE(chip_mapping)) {
  95                 dev_err(chip->dev,
  96                         "Failed to detect Marvell 88PM800:ChipID[0x%x]\n", val);
  97                 return -EINVAL;
  98         }
  99
 100         device_init_wakeup(&client->dev, 1);
 101
 102         /*
 103          * workaround: set g_pm80x_chip to the first probed chip. if the
 104          * second chip is probed, just point to the companion to each
 105          * other so that pm805 can access those specific register. would
 106          * remove it after HW chip fixes the issue.
 107          */
 108         if (!g_pm80x_chip)
 109                 g_pm80x_chip = chip;
 110         else {
 111                 chip->companion = g_pm80x_chip->client;
 112                 g_pm80x_chip->companion = chip->client;
 113         }
 114
 115         return 0;
 116 }
 117 EXPORT_SYMBOL_GPL(pm80x_init);
 118
 119 int pm80x_deinit(void)
 120 {
 121         /*
 122          * workaround: clear the dependency between pm800 and pm805.
 123          * would remove it after HW chip fixes the issue.
 124          */
 125         if (g_pm80x_chip->companion)
 126                 g_pm80x_chip->companion = NULL;
 127         else
 128                 g_pm80x_chip = NULL;
 129         return 0;
 130 }
 131 EXPORT_SYMBOL_GPL(pm80x_deinit);
 132
 133 #ifdef CONFIG_PM_SLEEP
 134 static int pm80x_suspend(struct device *dev)
 135 {
 136         struct i2c_client *client = container_of(dev, struct i2c_client, dev);
 137         struct pm80x_chip *chip = i2c_get_clientdata(client);
 138
 139         if (chip && chip->wu_flag)
 140                 if (device_may_wakeup(chip->dev))
 141                         enable_irq_wake(chip->irq);
 142
 143         return 0;
 144 }
 145
 146 static int pm80x_resume(struct device *dev)
 147 {
 148         struct i2c_client *client = container_of(dev, struct i2c_client, dev);
 149         struct pm80x_chip *chip = i2c_get_clientdata(client);
 150
 151         if (chip && chip->wu_flag)
 152                 if (device_may_wakeup(chip->dev))
 153                         disable_irq_wake(chip->irq);
 154
 155         return 0;
 156 }
 157 #endif
 158
 159 SIMPLE_DEV_PM_OPS(pm80x_pm_ops, pm80x_suspend, pm80x_resume);
 160 EXPORT_SYMBOL_GPL(pm80x_pm_ops);
 161
 162 MODULE_DESCRIPTION("I2C Driver for Marvell 88PM80x");
 163 MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
 164 MODULE_LICENSE("GPL");