/*
 *  chromeos_laptop.c - Driver to instantiate Chromebook i2c/smbus devices.
 *
 *  Author : Benson Leung <bleung@chromium.org>
 *
 *  Copyright (C) 2012 Google, Inc.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <linux/dmi.h>
#include <linux/i2c.h>
#include <linux/platform_data/atmel_mxt_ts.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/platform_device.h>

#define ATMEL_TP_I2C_ADDR       0x4b
#define ATMEL_TP_I2C_BL_ADDR    0x25
#define ATMEL_TS_I2C_ADDR       0x4a
#define ATMEL_TS_I2C_BL_ADDR    0x26
#define CYAPA_TP_I2C_ADDR       0x67
#define ELAN_TP_I2C_ADDR        0x15
#define ISL_ALS_I2C_ADDR        0x44
#define TAOS_ALS_I2C_ADDR       0x29

#define MAX_I2C_DEVICE_DEFERRALS        5

static struct i2c_client *als;
static struct i2c_client *tp;
static struct i2c_client *ts;

static const char *i2c_adapter_names[] = {
        "SMBus I801 adapter",
        "i915 gmbus vga",
        "i915 gmbus panel",
        "Synopsys DesignWare I2C adapter",
        "Synopsys DesignWare I2C adapter",
};

/* Keep this enum consistent with i2c_adapter_names */
enum i2c_adapter_type {
        I2C_ADAPTER_SMBUS = 0,
        I2C_ADAPTER_VGADDC,
        I2C_ADAPTER_PANEL,
        I2C_ADAPTER_DESIGNWARE_0,
        I2C_ADAPTER_DESIGNWARE_1,
};

enum i2c_peripheral_state {
        UNPROBED = 0,
        PROBED,
        TIMEDOUT,
};

struct i2c_peripheral {
        int (*add)(enum i2c_adapter_type type);
        enum i2c_adapter_type type;
        enum i2c_peripheral_state state;
        int tries;
};

#define MAX_I2C_PERIPHERALS 4

struct chromeos_laptop {
        struct i2c_peripheral i2c_peripherals[MAX_I2C_PERIPHERALS];
};

static struct chromeos_laptop *cros_laptop;

static struct i2c_board_info cyapa_device = {
        I2C_BOARD_INFO("cyapa", CYAPA_TP_I2C_ADDR),
        .flags          = I2C_CLIENT_WAKE,
};

static struct i2c_board_info elantech_device = {
        I2C_BOARD_INFO("elan_i2c", ELAN_TP_I2C_ADDR),
        .flags          = I2C_CLIENT_WAKE,
};

static struct i2c_board_info isl_als_device = {
        I2C_BOARD_INFO("isl29018", ISL_ALS_I2C_ADDR),
};

static struct i2c_board_info tsl2583_als_device = {
        I2C_BOARD_INFO("tsl2583", TAOS_ALS_I2C_ADDR),
};

static struct i2c_board_info tsl2563_als_device = {
        I2C_BOARD_INFO("tsl2563", TAOS_ALS_I2C_ADDR),
};

static int mxt_t19_keys[] = {
        KEY_RESERVED,
        KEY_RESERVED,
        KEY_RESERVED,
        KEY_RESERVED,
        KEY_RESERVED,
        BTN_LEFT
};

static struct mxt_platform_data atmel_224s_tp_platform_data = {
        .irqflags               = IRQF_TRIGGER_FALLING,
        .t19_num_keys           = ARRAY_SIZE(mxt_t19_keys),
        .t19_keymap             = mxt_t19_keys,
        .suspend_mode           = MXT_SUSPEND_T9_CTRL,
};

static struct i2c_board_info atmel_224s_tp_device = {
        I2C_BOARD_INFO("atmel_mxt_tp", ATMEL_TP_I2C_ADDR),
        .platform_data = &atmel_224s_tp_platform_data,
        .flags          = I2C_CLIENT_WAKE,
};

static struct mxt_platform_data atmel_1664s_platform_data = {
        .irqflags               = IRQF_TRIGGER_FALLING,
        .suspend_mode           = MXT_SUSPEND_T9_CTRL,
};

static struct i2c_board_info atmel_1664s_device = {
        I2C_BOARD_INFO("atmel_mxt_ts", ATMEL_TS_I2C_ADDR),
        .platform_data = &atmel_1664s_platform_data,
        .flags          = I2C_CLIENT_WAKE,
};

static struct i2c_client *__add_probed_i2c_device(
                const char *name,
                int bus,
                struct i2c_board_info *info,
                const unsigned short *alt_addr_list)
{
        const struct dmi_device *dmi_dev;
        const struct dmi_dev_onboard *dev_data;
        struct i2c_adapter *adapter;
        struct i2c_client *client = NULL;
        const unsigned short addr_list[] = { info->addr, I2C_CLIENT_END };

        if (bus < 0)
                return NULL;
        /*
         * If a name is specified, look for irq platform information stashed
         * in DMI_DEV_TYPE_DEV_ONBOARD by the Chrome OS custom system firmware.
         */
        if (name) {
                dmi_dev = dmi_find_device(DMI_DEV_TYPE_DEV_ONBOARD, name, NULL);
                if (!dmi_dev) {
                        pr_err("%s failed to dmi find device %s.\n",
                               __func__,
                               name);
                        return NULL;
                }
                dev_data = (struct dmi_dev_onboard *)dmi_dev->device_data;
                if (!dev_data) {
                        pr_err("%s failed to get data from dmi for %s.\n",
                               __func__, name);
                        return NULL;
                }
                info->irq = dev_data->instance;
        }

        adapter = i2c_get_adapter(bus);
        if (!adapter) {
                pr_err("%s failed to get i2c adapter %d.\n", __func__, bus);
                return NULL;
        }

        /*
         * Add the i2c device. If we can't detect it at the primary
         * address we scan secondary addresses. In any case the client
         * structure gets assigned primary address.
         */
        client = i2c_new_probed_device(adapter, info, addr_list, NULL);
        if (!client && alt_addr_list) {
                struct i2c_board_info dummy_info = {
                        I2C_BOARD_INFO("dummy", info->addr),
                };
                struct i2c_client *dummy;

                dummy = i2c_new_probed_device(adapter, &dummy_info,
                                              alt_addr_list, NULL);
                if (dummy) {
                        pr_debug("%s %d-%02x is probed at %02x\n",
                                  __func__, bus, info->addr, dummy->addr);
                        i2c_unregister_device(dummy);
                        client = i2c_new_device(adapter, info);
                }
        }

        if (!client)
                pr_notice("%s failed to register device %d-%02x\n",
                          __func__, bus, info->addr);
        else
                pr_debug("%s added i2c device %d-%02x\n",
                         __func__, bus, info->addr);

        i2c_put_adapter(adapter);
        return client;
}

struct i2c_lookup {
        const char *name;
        int instance;
        int n;
};

static int __find_i2c_adap(struct device *dev, void *data)
{
        struct i2c_lookup *lookup = data;
        static const char *prefix = "i2c-";
        struct i2c_adapter *adapter;

        if (strncmp(dev_name(dev), prefix, strlen(prefix)) != 0)
                return 0;
        adapter = to_i2c_adapter(dev);
        if (strncmp(adapter->name, lookup->name, strlen(lookup->name)) == 0 &&
            lookup->n++ == lookup->instance)
                return 1;
        return 0;
}

static int find_i2c_adapter_num(enum i2c_adapter_type type)
{
        struct device *dev = NULL;
        struct i2c_adapter *adapter;
        struct i2c_lookup lookup;

        memset(&lookup, 0, sizeof(lookup));
        lookup.name = i2c_adapter_names[type];
        lookup.instance = (type == I2C_ADAPTER_DESIGNWARE_1) ? 1 : 0;

        /* find the adapter by name */
        dev = bus_find_device(&i2c_bus_type, NULL, &lookup, __find_i2c_adap);
        if (!dev) {
                /* Adapters may appear later. Deferred probing will retry */
                pr_notice("%s: i2c adapter %s not found on system.\n", __func__,
                          lookup.name);
                return -ENODEV;
        }
        adapter = to_i2c_adapter(dev);
        return adapter->nr;
}

/*
 * Takes a list of addresses in addrs as such :
 * { addr1, ... , addrn, I2C_CLIENT_END };
 * add_probed_i2c_device will use i2c_new_probed_device
 * and probe for devices at all of the addresses listed.
 * Returns NULL if no devices found.
 * See Documentation/i2c/instantiating-devices for more information.
 */
static struct i2c_client *add_probed_i2c_device(
                const char *name,
                enum i2c_adapter_type type,
                struct i2c_board_info *info,
                const unsigned short *addrs)
{
        return __add_probed_i2c_device(name,
                                       find_i2c_adapter_num(type),
                                       info,
                                       addrs);
}

/*
 * Probes for a device at a single address, the one provided by
 * info->addr.
 * Returns NULL if no device found.
 */
static struct i2c_client *add_i2c_device(const char *name,
                                                enum i2c_adapter_type type,
                                                struct i2c_board_info *info)
{
        return __add_probed_i2c_device(name,
                                       find_i2c_adapter_num(type),
                                       info,
                                       NULL);
}

static int setup_cyapa_tp(enum i2c_adapter_type type)
{
        if (tp)
                return 0;

        /* add cyapa touchpad */
        tp = add_i2c_device("trackpad", type, &cyapa_device);
        return (!tp) ? -EAGAIN : 0;
}

static int setup_atmel_224s_tp(enum i2c_adapter_type type)
{
        const unsigned short addr_list[] = { ATMEL_TP_I2C_BL_ADDR,
                                             I2C_CLIENT_END };
        if (tp)
                return 0;

        /* add atmel mxt touchpad */
        tp = add_probed_i2c_device("trackpad", type,
                                   &atmel_224s_tp_device, addr_list);
        return (!tp) ? -EAGAIN : 0;
}

static int setup_elantech_tp(enum i2c_adapter_type type)
{
        if (tp)
                return 0;

        /* add elantech touchpad */
        tp = add_i2c_device("trackpad", type, &elantech_device);
        return (!tp) ? -EAGAIN : 0;
}

static int setup_atmel_1664s_ts(enum i2c_adapter_type type)
{
        const unsigned short addr_list[] = { ATMEL_TS_I2C_BL_ADDR,
                                             I2C_CLIENT_END };
        if (ts)
                return 0;

        /* add atmel mxt touch device */
        ts = add_probed_i2c_device("touchscreen", type,
                                   &atmel_1664s_device, addr_list);
        return (!ts) ? -EAGAIN : 0;
}

static int setup_isl29018_als(enum i2c_adapter_type type)
{
        if (als)
                return 0;

        /* add isl29018 light sensor */
        als = add_i2c_device("lightsensor", type, &isl_als_device);
        return (!als) ? -EAGAIN : 0;
}

static int setup_tsl2583_als(enum i2c_adapter_type type)
{
        if (als)
                return 0;

        /* add tsl2583 light sensor */
        als = add_i2c_device(NULL, type, &tsl2583_als_device);
        return (!als) ? -EAGAIN : 0;
}

static int setup_tsl2563_als(enum i2c_adapter_type type)
{
        if (als)
                return 0;

        /* add tsl2563 light sensor */
        als = add_i2c_device(NULL, type, &tsl2563_als_device);
        return (!als) ? -EAGAIN : 0;
}

static int __init chromeos_laptop_dmi_matched(const struct dmi_system_id *id)
{
        cros_laptop = (void *)id->driver_data;
        pr_debug("DMI Matched %s.\n", id->ident);

        /* Indicate to dmi_scan that processing is done. */
        return 1;
}

static int chromeos_laptop_probe(struct platform_device *pdev)
{
        int i;
        int ret = 0;

        for (i = 0; i < MAX_I2C_PERIPHERALS; i++) {
                struct i2c_peripheral *i2c_dev;

                i2c_dev = &cros_laptop->i2c_peripherals[i];

                /* No more peripherals. */
                if (i2c_dev->add == NULL)
                        break;

                if (i2c_dev->state == TIMEDOUT || i2c_dev->state == PROBED)
                        continue;

                /*
                 * Check that the i2c adapter is present.
                 * -EPROBE_DEFER if missing as the adapter may appear much
                 * later.
                 */
                if (find_i2c_adapter_num(i2c_dev->type) == -ENODEV) {
                        ret = -EPROBE_DEFER;
                        continue;
                }

                /* Add the device. */
                if (i2c_dev->add(i2c_dev->type) == -EAGAIN) {
                        /*
                         * Set -EPROBE_DEFER a limited num of times
                         * if device is not successfully added.
                         */
                        if (++i2c_dev->tries < MAX_I2C_DEVICE_DEFERRALS) {
                                ret = -EPROBE_DEFER;
                        } else {
                                /* Ran out of tries. */
                                pr_notice("%s: Ran out of tries for device.\n",
                                          __func__);
                                i2c_dev->state = TIMEDOUT;
                        }
                } else {
                        i2c_dev->state = PROBED;
                }
        }

        return ret;
}

static struct chromeos_laptop samsung_series_5_550 = {
        .i2c_peripherals = {
                /* Touchpad. */
                { .add = setup_cyapa_tp, I2C_ADAPTER_SMBUS },
                /* Light Sensor. */
                { .add = setup_isl29018_als, I2C_ADAPTER_SMBUS },
        },
};

static struct chromeos_laptop samsung_series_5 = {
        .i2c_peripherals = {
                /* Light Sensor. */
                { .add = setup_tsl2583_als, I2C_ADAPTER_SMBUS },
        },
};

static struct chromeos_laptop chromebook_pixel = {
        .i2c_peripherals = {
                /* Touch Screen. */
                { .add = setup_atmel_1664s_ts, I2C_ADAPTER_PANEL },
                /* Touchpad. */
                { .add = setup_atmel_224s_tp, I2C_ADAPTER_VGADDC },
                /* Light Sensor. */
                { .add = setup_isl29018_als, I2C_ADAPTER_PANEL },
        },
};

static struct chromeos_laptop hp_chromebook_14 = {
        .i2c_peripherals = {
                /* Touchpad. */
                { .add = setup_cyapa_tp, I2C_ADAPTER_DESIGNWARE_0 },
        },
};

static struct chromeos_laptop dell_chromebook_11 = {
        .i2c_peripherals = {
                /* Touchpad. */
                { .add = setup_cyapa_tp, I2C_ADAPTER_DESIGNWARE_0 },
                /* Elan Touchpad option. */
                { .add = setup_elantech_tp, I2C_ADAPTER_DESIGNWARE_0 },
        },
};

static struct chromeos_laptop toshiba_cb35 = {
        .i2c_peripherals = {
                /* Touchpad. */
                { .add = setup_cyapa_tp, I2C_ADAPTER_DESIGNWARE_0 },
        },
};

static struct chromeos_laptop acer_c7_chromebook = {
        .i2c_peripherals = {
                /* Touchpad. */
                { .add = setup_cyapa_tp, I2C_ADAPTER_SMBUS },
        },
};

static struct chromeos_laptop acer_ac700 = {
        .i2c_peripherals = {
                /* Light Sensor. */
                { .add = setup_tsl2563_als, I2C_ADAPTER_SMBUS },
        },
};

static struct chromeos_laptop acer_c720 = {
        .i2c_peripherals = {
                /* Touchscreen. */
                { .add = setup_atmel_1664s_ts, I2C_ADAPTER_DESIGNWARE_1 },
                /* Touchpad. */
                { .add = setup_cyapa_tp, I2C_ADAPTER_DESIGNWARE_0 },
                /* Elan Touchpad option. */
                { .add = setup_elantech_tp, I2C_ADAPTER_DESIGNWARE_0 },
                /* Light Sensor. */
                { .add = setup_isl29018_als, I2C_ADAPTER_DESIGNWARE_1 },
        },
};

static struct chromeos_laptop hp_pavilion_14_chromebook = {
        .i2c_peripherals = {
                /* Touchpad. */
                { .add = setup_cyapa_tp, I2C_ADAPTER_SMBUS },
        },
};

static struct chromeos_laptop cr48 = {
        .i2c_peripherals = {
                /* Light Sensor. */
                { .add = setup_tsl2563_als, I2C_ADAPTER_SMBUS },
        },
};

#define _CBDD(board_) \
        .callback = chromeos_laptop_dmi_matched, \
        .driver_data = (void *)&board_

static struct dmi_system_id chromeos_laptop_dmi_table[] __initdata = {
        {
                .ident = "Samsung Series 5 550",
                .matches = {
                        DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "Lumpy"),
                },
                _CBDD(samsung_series_5_550),
        },
        {
                .ident = "Samsung Series 5",
                .matches = {
                        DMI_MATCH(DMI_PRODUCT_NAME, "Alex"),
                },
                _CBDD(samsung_series_5),
        },
        {
                .ident = "Chromebook Pixel",
                .matches = {
                        DMI_MATCH(DMI_SYS_VENDOR, "GOOGLE"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "Link"),
                },
                _CBDD(chromebook_pixel),
        },
        {
                .ident = "Wolf",
                .matches = {
                        DMI_MATCH(DMI_BIOS_VENDOR, "coreboot"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "Wolf"),
                },
                _CBDD(dell_chromebook_11),
        },
        {
                .ident = "HP Chromebook 14",
                .matches = {
                        DMI_MATCH(DMI_BIOS_VENDOR, "coreboot"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "Falco"),
                },
                _CBDD(hp_chromebook_14),
        },
        {
                .ident = "Toshiba CB35",
                .matches = {
                        DMI_MATCH(DMI_BIOS_VENDOR, "coreboot"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "Leon"),
                },
                _CBDD(toshiba_cb35),
        },
        {
                .ident = "Acer C7 Chromebook",
                .matches = {
                        DMI_MATCH(DMI_PRODUCT_NAME, "Parrot"),
                },
                _CBDD(acer_c7_chromebook),
        },
        {
                .ident = "Acer AC700",
                .matches = {
                        DMI_MATCH(DMI_PRODUCT_NAME, "ZGB"),
                },
                _CBDD(acer_ac700),
        },
        {
                .ident = "Acer C720",
                .matches = {
                        DMI_MATCH(DMI_PRODUCT_NAME, "Peppy"),
                },
                _CBDD(acer_c720),
        },
        {
                .ident = "HP Pavilion 14 Chromebook",
                .matches = {
                        DMI_MATCH(DMI_PRODUCT_NAME, "Butterfly"),
                },
                _CBDD(hp_pavilion_14_chromebook),
        },
        {
                .ident = "Cr-48",
                .matches = {
                        DMI_MATCH(DMI_PRODUCT_NAME, "Mario"),
                },
                _CBDD(cr48),
        },
        { }
};
MODULE_DEVICE_TABLE(dmi, chromeos_laptop_dmi_table);

static struct platform_device *cros_platform_device;

static struct platform_driver cros_platform_driver = {
        .driver = {
                .name = "chromeos_laptop",
        },
        .probe = chromeos_laptop_probe,
};

static int __init chromeos_laptop_init(void)
{
        int ret;

        if (!dmi_check_system(chromeos_laptop_dmi_table)) {
                pr_debug("%s unsupported system.\n", __func__);
                return -ENODEV;
        }

        ret = platform_driver_register(&cros_platform_driver);
        if (ret)
                return ret;

        cros_platform_device = platform_device_alloc("chromeos_laptop", -1);
        if (!cros_platform_device) {
                ret = -ENOMEM;
                goto fail_platform_device1;
        }

        ret = platform_device_add(cros_platform_device);
        if (ret)
                goto fail_platform_device2;

        return 0;

fail_platform_device2:
        platform_device_put(cros_platform_device);
fail_platform_device1:
        platform_driver_unregister(&cros_platform_driver);
        return ret;
}

static void __exit chromeos_laptop_exit(void)
{
        if (als)
                i2c_unregister_device(als);
        if (tp)
                i2c_unregister_device(tp);
        if (ts)
                i2c_unregister_device(ts);

        platform_device_unregister(cros_platform_device);
        platform_driver_unregister(&cros_platform_driver);
}

module_init(chromeos_laptop_init);
module_exit(chromeos_laptop_exit);

MODULE_DESCRIPTION("Chrome OS Laptop driver");
MODULE_AUTHOR("Benson Leung <bleung@chromium.org>");
MODULE_LICENSE("GPL");