LXR linux/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
  26struct pm80x_chip_mapping {
  27        unsigned int    id;
  28        int             type;
  29};
  30
  31static 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 */
  43static struct pm80x_chip *g_pm80x_chip;
  44
  45const struct regmap_config pm80x_regmap_config = {
  46        .reg_bits = 8,
  47        .val_bits = 8,
  48};
  49EXPORT_SYMBOL_GPL(pm80x_regmap_config);
  50
  51
  52int 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}
 117EXPORT_SYMBOL_GPL(pm80x_init);
 118
 119int 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}
 131EXPORT_SYMBOL_GPL(pm80x_deinit);
 132
 133#ifdef CONFIG_PM_SLEEP
 134static 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
 146static 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
 159SIMPLE_DEV_PM_OPS(pm80x_pm_ops, pm80x_suspend, pm80x_resume);
 160EXPORT_SYMBOL_GPL(pm80x_pm_ops);
 161
 162MODULE_DESCRIPTION("I2C Driver for Marvell 88PM80x");
 163MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
 164MODULE_LICENSE("GPL");
 165