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alistair23-linux/drivers/iio/light/bh1780.c
Linus Walleij 0dd09ca419 iio: light: bh1780: assign a static name 
Using the struct i2c_device->id field for naming the light sensor
is a bad idea: when booting from the pure device tree this is NULL
and that causes the device not to have the "name" property in
sysfs and that in turn confuses the "lsiio" command to stop listing
devices.

So instead of using the device .id, use the hard string "bh1780",
which works just fine.

Fixes: 1f0477f183 ("iio: light: new driver for the ROHM BH1780")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-05-29 19:51:29 +01:00

300 lines
7.2 KiB
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/*
* ROHM 1780GLI Ambient Light Sensor Driver
*
* Copyright (C) 2016 Linaro Ltd.
* Author: Linus Walleij <linus.walleij@linaro.org>
* Loosely based on the previous BH1780 ALS misc driver
* Copyright (C) 2010 Texas Instruments
* Author: Hemanth V <hemanthv@ti.com>
*/
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/pm_runtime.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/bitops.h>
#define BH1780_CMD_BIT BIT(7)
#define BH1780_REG_CONTROL 0x00
#define BH1780_REG_PARTID 0x0A
#define BH1780_REG_MANFID 0x0B
#define BH1780_REG_DLOW 0x0C
#define BH1780_REG_DHIGH 0x0D
#define BH1780_REVMASK GENMASK(3,0)
#define BH1780_POWMASK GENMASK(1,0)
#define BH1780_POFF (0x0)
#define BH1780_PON (0x3)
/* power on settling time in ms */
#define BH1780_PON_DELAY 2
/* max time before value available in ms */
#define BH1780_INTERVAL 250
struct bh1780_data {
struct i2c_client *client;
};
static int bh1780_write(struct bh1780_data *bh1780, u8 reg, u8 val)
{
int ret = i2c_smbus_write_byte_data(bh1780->client,
BH1780_CMD_BIT | reg,
val);
if (ret < 0)
dev_err(&bh1780->client->dev,
"i2c_smbus_write_byte_data failed error "
"%d, register %01x\n",
ret, reg);
return ret;
}
static int bh1780_read(struct bh1780_data *bh1780, u8 reg)
{
int ret = i2c_smbus_read_byte_data(bh1780->client,
BH1780_CMD_BIT | reg);
if (ret < 0)
dev_err(&bh1780->client->dev,
"i2c_smbus_read_byte_data failed error "
"%d, register %01x\n",
ret, reg);
return ret;
}
static int bh1780_read_word(struct bh1780_data *bh1780, u8 reg)
{
int ret = i2c_smbus_read_word_data(bh1780->client,
BH1780_CMD_BIT | reg);
if (ret < 0)
dev_err(&bh1780->client->dev,
"i2c_smbus_read_word_data failed error "
"%d, register %01x\n",
ret, reg);
return ret;
}
static int bh1780_debugfs_reg_access(struct iio_dev *indio_dev,
unsigned int reg, unsigned int writeval,
unsigned int *readval)
{
struct bh1780_data *bh1780 = iio_priv(indio_dev);
int ret;
if (!readval)
return bh1780_write(bh1780, (u8)reg, (u8)writeval);
ret = bh1780_read(bh1780, (u8)reg);
if (ret < 0)
return ret;
*readval = ret;
return 0;
}
static int bh1780_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct bh1780_data *bh1780 = iio_priv(indio_dev);
int value;
switch (mask) {
case IIO_CHAN_INFO_RAW:
switch (chan->type) {
case IIO_LIGHT:
pm_runtime_get_sync(&bh1780->client->dev);
value = bh1780_read_word(bh1780, BH1780_REG_DLOW);
if (value < 0)
return value;
pm_runtime_mark_last_busy(&bh1780->client->dev);
pm_runtime_put_autosuspend(&bh1780->client->dev);
*val = value;
return IIO_VAL_INT;
default:
return -EINVAL;
}
case IIO_CHAN_INFO_INT_TIME:
*val = 0;
*val2 = BH1780_INTERVAL * 1000;
return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
}
static const struct iio_info bh1780_info = {
.driver_module = THIS_MODULE,
.read_raw = bh1780_read_raw,
.debugfs_reg_access = bh1780_debugfs_reg_access,
};
static const struct iio_chan_spec bh1780_channels[] = {
{
.type = IIO_LIGHT,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_INT_TIME)
}
};
static int bh1780_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
int ret;
struct bh1780_data *bh1780;
struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
struct iio_dev *indio_dev;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
return -EIO;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*bh1780));
if (!indio_dev)
return -ENOMEM;
bh1780 = iio_priv(indio_dev);
bh1780->client = client;
i2c_set_clientdata(client, indio_dev);
/* Power up the device */
ret = bh1780_write(bh1780, BH1780_REG_CONTROL, BH1780_PON);
if (ret < 0)
return ret;
msleep(BH1780_PON_DELAY);
pm_runtime_get_noresume(&client->dev);
pm_runtime_set_active(&client->dev);
pm_runtime_enable(&client->dev);
ret = bh1780_read(bh1780, BH1780_REG_PARTID);
if (ret < 0)
goto out_disable_pm;
dev_info(&client->dev,
"Ambient Light Sensor, Rev : %lu\n",
(ret & BH1780_REVMASK));
/*
* As the device takes 250 ms to even come up with a fresh
* measurement after power-on, do not shut it down unnecessarily.
* Set autosuspend to a five seconds.
*/
pm_runtime_set_autosuspend_delay(&client->dev, 5000);
pm_runtime_use_autosuspend(&client->dev);
pm_runtime_put(&client->dev);
indio_dev->dev.parent = &client->dev;
indio_dev->info = &bh1780_info;
indio_dev->name = "bh1780";
indio_dev->channels = bh1780_channels;
indio_dev->num_channels = ARRAY_SIZE(bh1780_channels);
indio_dev->modes = INDIO_DIRECT_MODE;
ret = iio_device_register(indio_dev);
if (ret)
goto out_disable_pm;
return 0;
out_disable_pm:
pm_runtime_put_noidle(&client->dev);
pm_runtime_disable(&client->dev);
return ret;
}
static int bh1780_remove(struct i2c_client *client)
{
struct iio_dev *indio_dev = i2c_get_clientdata(client);
struct bh1780_data *bh1780 = iio_priv(indio_dev);
int ret;
iio_device_unregister(indio_dev);
pm_runtime_get_sync(&client->dev);
pm_runtime_put_noidle(&client->dev);
pm_runtime_disable(&client->dev);
ret = bh1780_write(bh1780, BH1780_REG_CONTROL, BH1780_POFF);
if (ret < 0) {
dev_err(&client->dev, "failed to power off\n");
return ret;
}
return 0;
}
#ifdef CONFIG_PM
static int bh1780_runtime_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct iio_dev *indio_dev = i2c_get_clientdata(client);
struct bh1780_data *bh1780 = iio_priv(indio_dev);
int ret;
ret = bh1780_write(bh1780, BH1780_REG_CONTROL, BH1780_POFF);
if (ret < 0) {
dev_err(dev, "failed to runtime suspend\n");
return ret;
}
return 0;
}
static int bh1780_runtime_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct iio_dev *indio_dev = i2c_get_clientdata(client);
struct bh1780_data *bh1780 = iio_priv(indio_dev);
int ret;
ret = bh1780_write(bh1780, BH1780_REG_CONTROL, BH1780_PON);
if (ret < 0) {
dev_err(dev, "failed to runtime resume\n");
return ret;
}
/* Wait for power on, then for a value to be available */
msleep(BH1780_PON_DELAY + BH1780_INTERVAL);
return 0;
}
#endif /* CONFIG_PM */
static const struct dev_pm_ops bh1780_dev_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
pm_runtime_force_resume)
SET_RUNTIME_PM_OPS(bh1780_runtime_suspend,
bh1780_runtime_resume, NULL)
};
static const struct i2c_device_id bh1780_id[] = {
{ "bh1780", 0 },
{ },
};
MODULE_DEVICE_TABLE(i2c, bh1780_id);
#ifdef CONFIG_OF
static const struct of_device_id of_bh1780_match[] = {
{ .compatible = "rohm,bh1780gli", },
{},
};
MODULE_DEVICE_TABLE(of, of_bh1780_match);
#endif
static struct i2c_driver bh1780_driver = {
.probe = bh1780_probe,
.remove = bh1780_remove,
.id_table = bh1780_id,
.driver = {
.name = "bh1780",
.pm = &bh1780_dev_pm_ops,
.of_match_table = of_match_ptr(of_bh1780_match),
},
};
module_i2c_driver(bh1780_driver);
MODULE_DESCRIPTION("ROHM BH1780GLI Ambient Light Sensor Driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
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