root/drivers/misc/lis3lv02d/lis3lv02d_i2c.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * drivers/hwmon/lis3lv02d_i2c.c
 *
 * Implements I2C interface for lis3lv02d (STMicroelectronics) accelerometer.
 * Driver is based on corresponding SPI driver written by Daniel Mack
 * (lis3lv02d_spi.c (C) 2009 Daniel Mack <daniel@caiaq.de> ).
 *
 * Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
 *
 * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/pm_runtime.h>
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/of_device.h>

#include "lis3lv02d.h"

#define DRV_NAME        "lis3lv02d_i2c"

static const char reg_vdd[]    = "Vdd";
static const char reg_vdd_io[] = "Vdd_IO";

static int lis3_reg_ctrl(struct lis3lv02d *lis3, bool state)
{
        int ret;
        if (state == LIS3_REG_OFF) {
                ret = regulator_bulk_disable(ARRAY_SIZE(lis3->regulators),
                                        lis3->regulators);
        } else {
                ret = regulator_bulk_enable(ARRAY_SIZE(lis3->regulators),
                                        lis3->regulators);
                /* Chip needs time to wakeup. Not mentioned in datasheet */
                usleep_range(10000, 20000);
        }
        return ret;
}

static inline s32 lis3_i2c_write(struct lis3lv02d *lis3, int reg, u8 value)
{
        struct i2c_client *c = lis3->bus_priv;
        return i2c_smbus_write_byte_data(c, reg, value);
}

static inline s32 lis3_i2c_read(struct lis3lv02d *lis3, int reg, u8 *v)
{
        struct i2c_client *c = lis3->bus_priv;
        *v = i2c_smbus_read_byte_data(c, reg);
        return 0;
}

static inline s32 lis3_i2c_blockread(struct lis3lv02d *lis3, int reg, int len,
                                u8 *v)
{
        struct i2c_client *c = lis3->bus_priv;
        reg |= (1 << 7); /* 7th bit enables address auto incrementation */
        return i2c_smbus_read_i2c_block_data(c, reg, len, v);
}

static int lis3_i2c_init(struct lis3lv02d *lis3)
{
        u8 reg;
        int ret;

        lis3_reg_ctrl(lis3, LIS3_REG_ON);

        lis3->read(lis3, WHO_AM_I, &reg);
        if (reg != lis3->whoami)
                printk(KERN_ERR "lis3: power on failure\n");

        /* power up the device */
        ret = lis3->read(lis3, CTRL_REG1, &reg);
        if (ret < 0)
                return ret;

        if (lis3->whoami == WAI_3DLH)
                reg |= CTRL1_PM0 | CTRL1_Xen | CTRL1_Yen | CTRL1_Zen;
        else
                reg |= CTRL1_PD0 | CTRL1_Xen | CTRL1_Yen | CTRL1_Zen;

        return lis3->write(lis3, CTRL_REG1, reg);
}

/* Default axis mapping but it can be overwritten by platform data */
static union axis_conversion lis3lv02d_axis_map =
        { .as_array = { LIS3_DEV_X, LIS3_DEV_Y, LIS3_DEV_Z } };

#ifdef CONFIG_OF
static const struct of_device_id lis3lv02d_i2c_dt_ids[] = {
        { .compatible = "st,lis3lv02d" },
        {}
};
MODULE_DEVICE_TABLE(of, lis3lv02d_i2c_dt_ids);
#endif

static int lis3lv02d_i2c_probe(struct i2c_client *client)
{
        int ret = 0;
        struct lis3lv02d_platform_data *pdata = client->dev.platform_data;

#ifdef CONFIG_OF
        if (of_match_device(lis3lv02d_i2c_dt_ids, &client->dev)) {
                lis3_dev.of_node = client->dev.of_node;
                ret = lis3lv02d_init_dt(&lis3_dev);
                if (ret)
                        return ret;
                pdata = lis3_dev.pdata;
        }
#endif

        if (pdata) {
                if ((pdata->driver_features & LIS3_USE_BLOCK_READ) &&
                        (i2c_check_functionality(client->adapter,
                                                I2C_FUNC_SMBUS_I2C_BLOCK)))
                        lis3_dev.blkread  = lis3_i2c_blockread;

                if (pdata->axis_x)
                        lis3lv02d_axis_map.x = pdata->axis_x;

                if (pdata->axis_y)
                        lis3lv02d_axis_map.y = pdata->axis_y;

                if (pdata->axis_z)
                        lis3lv02d_axis_map.z = pdata->axis_z;

                if (pdata->setup_resources)
                        ret = pdata->setup_resources();

                if (ret)
                        goto fail;
        }

        lis3_dev.regulators[0].supply = reg_vdd;
        lis3_dev.regulators[1].supply = reg_vdd_io;
        ret = regulator_bulk_get(&client->dev,
                                 ARRAY_SIZE(lis3_dev.regulators),
                                 lis3_dev.regulators);
        if (ret < 0)
                goto fail;

        lis3_dev.pdata    = pdata;
        lis3_dev.bus_priv = client;
        lis3_dev.init     = lis3_i2c_init;
        lis3_dev.read     = lis3_i2c_read;
        lis3_dev.write    = lis3_i2c_write;
        lis3_dev.reg_ctrl = lis3_reg_ctrl;
        lis3_dev.irq      = client->irq;
        lis3_dev.ac       = lis3lv02d_axis_map;
        lis3_dev.pm_dev   = &client->dev;

        i2c_set_clientdata(client, &lis3_dev);

        /* Provide power over the init call */
        lis3_reg_ctrl(&lis3_dev, LIS3_REG_ON);

        ret = lis3lv02d_init_device(&lis3_dev);

        lis3_reg_ctrl(&lis3_dev, LIS3_REG_OFF);

        if (ret)
                goto fail2;
        return 0;

fail2:
        regulator_bulk_free(ARRAY_SIZE(lis3_dev.regulators),
                                lis3_dev.regulators);
fail:
        if (pdata && pdata->release_resources)
                pdata->release_resources();
        return ret;
}

static void lis3lv02d_i2c_remove(struct i2c_client *client)
{
        struct lis3lv02d *lis3 = i2c_get_clientdata(client);
        struct lis3lv02d_platform_data *pdata = client->dev.platform_data;

        if (pdata && pdata->release_resources)
                pdata->release_resources();

        lis3lv02d_joystick_disable(lis3);
        lis3lv02d_remove_fs(&lis3_dev);

        regulator_bulk_free(ARRAY_SIZE(lis3->regulators),
                            lis3_dev.regulators);
}

#ifdef CONFIG_PM_SLEEP
static int lis3lv02d_i2c_suspend(struct device *dev)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct lis3lv02d *lis3 = i2c_get_clientdata(client);

        /* Turn on for wakeup if turned off by runtime suspend */
        if (lis3->pdata && lis3->pdata->wakeup_flags) {
                if (pm_runtime_suspended(dev))
                        lis3lv02d_poweron(lis3);
        /* For non wakeup turn off if not already turned off by runtime suspend */
        } else if (!pm_runtime_suspended(dev))
                lis3lv02d_poweroff(lis3);

        return 0;
}

static int lis3lv02d_i2c_resume(struct device *dev)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct lis3lv02d *lis3 = i2c_get_clientdata(client);

        /* Turn back off if turned on for wakeup and runtime suspended*/
        if (lis3->pdata && lis3->pdata->wakeup_flags) {
                if (pm_runtime_suspended(dev))
                        lis3lv02d_poweroff(lis3);
        /* For non wakeup turn back on if not runtime suspended */
        } else if (!pm_runtime_suspended(dev))
                lis3lv02d_poweron(lis3);

        return 0;
}
#endif /* CONFIG_PM_SLEEP */

#ifdef CONFIG_PM
static int lis3_i2c_runtime_suspend(struct device *dev)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct lis3lv02d *lis3 = i2c_get_clientdata(client);

        lis3lv02d_poweroff(lis3);
        return 0;
}

static int lis3_i2c_runtime_resume(struct device *dev)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct lis3lv02d *lis3 = i2c_get_clientdata(client);

        lis3lv02d_poweron(lis3);
        return 0;
}
#endif /* CONFIG_PM */

static const struct i2c_device_id lis3lv02d_id[] = {
        {"lis3lv02d", LIS3LV02D},
        {"lis331dlh", LIS331DLH},
        {}
};

MODULE_DEVICE_TABLE(i2c, lis3lv02d_id);

static const struct dev_pm_ops lis3_pm_ops = {
        SET_SYSTEM_SLEEP_PM_OPS(lis3lv02d_i2c_suspend,
                                lis3lv02d_i2c_resume)
        SET_RUNTIME_PM_OPS(lis3_i2c_runtime_suspend,
                           lis3_i2c_runtime_resume,
                           NULL)
};

static struct i2c_driver lis3lv02d_i2c_driver = {
        .driver  = {
                .name   = DRV_NAME,
                .pm     = &lis3_pm_ops,
                .of_match_table = of_match_ptr(lis3lv02d_i2c_dt_ids),
        },
        .probe = lis3lv02d_i2c_probe,
        .remove = lis3lv02d_i2c_remove,
        .id_table = lis3lv02d_id,
};

module_i2c_driver(lis3lv02d_i2c_driver);

MODULE_AUTHOR("Nokia Corporation");
MODULE_DESCRIPTION("lis3lv02d I2C interface");
MODULE_LICENSE("GPL");