Hello,
some comments inline;
new drivers should not go to staging but to mainline directly
regards, p.
> Signed-off-by: Kevin Tsai <ktsai@xxxxxxxxxxxxxxxx>
> ---
> drivers/staging/iio/light/Kconfig | 10 +
> drivers/staging/iio/light/Makefile | 1 +
> drivers/staging/iio/light/cm3218.c | 581 ++++++++++++++++++++++++++++++++++++
> 3 files changed, 592 insertions(+)
> create mode 100644 drivers/staging/iio/light/cm3218.c
>
> diff --git a/drivers/staging/iio/light/Kconfig b/drivers/staging/iio/light/Kconfig
> index ca8d6e6..647af0c 100644
> --- a/drivers/staging/iio/light/Kconfig
> +++ b/drivers/staging/iio/light/Kconfig
> @@ -40,4 +40,14 @@ config TSL2x7x
> tmd2672, tsl2772, tmd2772 devices.
> Provides iio_events and direct access via sysfs.
>
> +config SENSORS_CM3218
> + tristate "CM3218 Ambient Light Sensor"
> + depends on I2C
> + help
> + Say Y here if you have a Capella Micro CM3218 Ambient Light Sensor.
> +
> + To compile this driver as a module, choose M here. This module
> + will be called to 'cm3218'. It will access ALS data via iio sysfs.
> + This is recommended.
> +
> endmenu
> diff --git a/drivers/staging/iio/light/Makefile b/drivers/staging/iio/light/Makefile
> index 9960fdf..63020ab 100644
> --- a/drivers/staging/iio/light/Makefile
> +++ b/drivers/staging/iio/light/Makefile
> @@ -6,3 +6,4 @@ obj-$(CONFIG_SENSORS_ISL29018) += isl29018.o
> obj-$(CONFIG_SENSORS_ISL29028) += isl29028.o
> obj-$(CONFIG_TSL2583) += tsl2583.o
> obj-$(CONFIG_TSL2x7x) += tsl2x7x_core.o
> +obj-$(CONFIG_SENSORS_CM3218) += cm3218.o
> diff --git a/drivers/staging/iio/light/cm3218.c b/drivers/staging/iio/light/cm3218.c
> new file mode 100644
> index 0000000..9c2584d
> --- /dev/null
> +++ b/drivers/staging/iio/light/cm3218.c
> @@ -0,0 +1,581 @@
> +/*
> + * A iio driver for CM3218 Ambient Light Sensor.
> + *
> + * IIO driver for monitoring ambient light intensity in lux.
> + *
> + * Copyright (c) 2013, Capella Microsystems 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.,
> + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/i2c.h>
> +#include <linux/err.h>
> +#include <linux/mutex.h>
> +#include <linux/delay.h>
> +#include <linux/slab.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +
> +/*
> + * SMBus ARA address
maybe Address for consistency?
> + */
> +#define CM3218_ADDR_ARA 0x0C
> +
> +/*
> + * CM3218 CMD Registers
> + */
> +#define CM3218_REG_ADDR_CMD 0x00
> +#define CM3218_CMD_ALS_SD 0x0001
> +#define CM3218_CMD_ALS_INT_EN 0x0002
> +#define CM3218_CMD_ALS_IT_SHIFT 6
> +#define CM3218_CMD_ALS_IT_MASK (3 << CM3218_CMD_ALS_IT_SHIFT)
> +#define CM3218_CMD_ALS_IT_05T (0 << CM3218_CMD_ALS_IT_SHIFT)
> +#define CM3218_CMD_ALS_IT_1T (1 << CM3218_CMD_ALS_IT_SHIFT)
> +#define CM3218_CMD_ALS_IT_2T (2 << CM3218_CMD_ALS_IT_SHIFT)
> +#define CM3218_CMD_ALS_IT_4T (3 << CM3218_CMD_ALS_IT_SHIFT)
> +#define CM3218_DEFAULT_CMD (CM3218_CMD_ALS_IT_1T)
no parenthesis needed
> +
> +#define CM3218_REG_ADDR_ALS_WH 0x01
> +#define CM3218_DEFAULT_ALS_WH 0xFFFF
> +
> +#define CM3218_REG_ADDR_ALS_WL 0x02
> +#define CM3218_DEFAULT_ALS_WL 0x0000
> +
> +#define CM3218_REG_ADDR_ALS 0x04
> +
> +#define CM3218_REG_ADDR_STATUS 0x06
> +
> +#define CM3218_REG_ADDR_ID 0x07
> +
> +/*
> + * Software Parameters
> + */
> +#define CM3218_MAX_CACHE_REGS (0x03+1) /* Reg.0x00 to 0x03 */
> +
> +/*
> + * Features
> + */
> +#define CM3218_DEBUG
> +
> +static const unsigned short normal_i2c[] = {
> + 0x10, 0x48, I2C_CLIENT_END };
> +
> +struct cm3218_chip {
> + struct i2c_client *client;
> + struct mutex lock;
> + unsigned int lensfactor;
> + bool suspended;
> + u16 reg_cache[CM3218_MAX_CACHE_REGS];
> +};
> +
> +static int cm3218_read_ara(struct i2c_client *client)
> +{
> + int status;
> + unsigned short addr;
> +
> + addr = client->addr;
> + client->addr = CM3218_ADDR_ARA;
> + status = i2c_smbus_read_byte(client);
> + client->addr = addr;
> +
> + if (status < 0)
> + return -ENODEV;
> +
> + return 0;
> +}
> +
> +static int cm3218_write(struct i2c_client *client, u8 reg, u16 value)
> +{
> + u16 regval;
> + int ret;
> + struct cm3218_chip *chip = iio_priv(i2c_get_clientdata(client));
> +
> +#ifdef CM3218_DEBUG
> + dev_err(&client->dev,
> + "Write to device register 0x%02X with 0x%04X\n", reg, value);
> +#endif /* CM3218_DEBUG */
dev_dbg? and no _DEBUG
> + regval = cpu_to_le16(value);
> + ret = i2c_smbus_write_word_data(client, reg, regval);
> + if (ret) {
> + dev_err(&client->dev, "Write to device fails: 0x%x\n", ret);
> + } else {
> + /* Update cache */
> + if (reg < CM3218_MAX_CACHE_REGS)
> + chip->reg_cache[reg] = value;
> + }
> +
> + return ret;
> +}
there is regmap for caching register contents; maybe overkill..
> +
> +static int cm3218_read(struct i2c_client *client, u8 reg)
> +{
> + int regval;
> + int status;
> + struct cm3218_chip *chip = iio_priv(i2c_get_clientdata(client));
> +
> + if (reg < CM3218_MAX_CACHE_REGS) {
> + regval = chip->reg_cache[reg];
> + } else {
> + status = i2c_smbus_read_word_data(client, reg);
> + if (status < 0) {
> + dev_err(&client->dev,
> + "Error in reading Reg.0x%02X\n", reg);
> + return status;
> + }
> + regval = le16_to_cpu(status);
> +#ifdef CM3218_DEBUG
> + dev_err(&client->dev,
> + "Read from device register 0x%02X = 0x%04X\n",
> + reg, regval);
> +#endif /* CM3218_DEBUG */
> + }
> +
> + return regval;
> +}
> +
> +static int cm3218_read_sensor_input(struct i2c_client *client)
> +{
> + int status;
> + int lux;
> +
> + status = cm3218_read(client, CM3218_REG_ADDR_ALS);
> + if (status < 0) {
> + dev_err(&client->dev, "Error in reading Lux DATA\n");
> + return status;
> + }
> + lux = status;
> +
> + dev_vdbg(&client->dev, "lux = %u\n", lux);
> +
> + return lux;
> +}
> +
> +static int cm3218_read_lux(struct i2c_client *client, int *lux)
> +{
> + struct cm3218_chip *chip = iio_priv(i2c_get_clientdata(client));
> + int lux_data;
> +
> + lux_data = cm3218_read_sensor_input(client);
> +
> + if (lux_data < 0)
> + return lux_data;
> +
> + *lux = lux_data * chip->lensfactor;
> + *lux /= 1000;
> + return 0;
> +}
these read wrappers could probably be avoided; most of the code is
cascaded error handling
> +
> +/* Sysfs interface */
> +/* lensfactor */
comment style
> +static ssize_t show_lensfactor(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct iio_dev *indio_dev = dev_get_drvdata(dev);
> + struct cm3218_chip *chip = iio_priv(indio_dev);
> +
> + return sprintf(buf, "%d\n", chip->lensfactor);
> +}
the sysfs interface seems to be redundant; there is also CALIBSCALE
> +
> +static ssize_t store_lensfactor(struct device *dev,
> + struct device_attribute *attr, const char *buf, size_t count)
> +{
> + struct iio_dev *indio_dev = dev_get_drvdata(dev);
> + struct cm3218_chip *chip = iio_priv(indio_dev);
> + unsigned long lval;
> +
> +/*
> + lval = kstrtoul(buf, NULL, 10);
> + if (lval == 0)
> + return -EINVAL;
> +*/
remove comment before submission
> + if (kstrtoul(buf, 10, &lval))
> + return -EINVAL;
> +
> + mutex_lock(&chip->lock);
> + chip->lensfactor = lval;
> + mutex_unlock(&chip->lock);
> +
> + return count;
> +}
> +
> +static ssize_t get_sensor_data(struct device *dev, char *buf)
> +{
> + struct iio_dev *indio_dev = dev_get_drvdata(dev);
> + struct cm3218_chip *chip = iio_priv(indio_dev);
> + struct i2c_client *client = chip->client;
> + int value = 0;
> + int status;
> +
> + mutex_lock(&chip->lock);
> + if (chip->suspended) {
> + mutex_unlock(&chip->lock);
> + return -EBUSY;
> + }
> +
> + status = cm3218_read_lux(client, &value);
extra space here
> +
> + if (status < 0) {
> + dev_err(&client->dev, "Error in Reading data");
> + mutex_unlock(&chip->lock);
> + return status;
> + }
> +
> + mutex_unlock(&chip->lock);
> +
> + return sprintf(buf, "%d\n", value);
> +}
> +
> +
> +/* Read lux */
> +static ssize_t show_lux(struct device *dev,
> + struct device_attribute *devattr, char *buf)
> +{
> + return get_sensor_data(dev, buf);
> +}
> +
> +#ifdef CM3218_DEBUG
> +/* windows_high */
there would be debugfs_reg_access in iio_info
> +static ssize_t show_cmd(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct iio_dev *indio_dev = dev_get_drvdata(dev);
> + struct cm3218_chip *chip = iio_priv(indio_dev);
> + struct i2c_client *client = chip->client;
> + int status;
> +
> + status = cm3218_read(client, CM3218_REG_ADDR_CMD);
> + if (status < 0) {
> + dev_err(dev, "Error in getting CM3218_REG_ADDR_CMD\n");
> + return status;
> + }
> +
> + return sprintf(buf, "%u\n", status);
> +}
> +
> +static ssize_t store_cmd(struct device *dev,
> + struct device_attribute *attr, const char *buf, size_t count)
> +{
> + struct iio_dev *indio_dev = dev_get_drvdata(dev);
> + struct cm3218_chip *chip = iio_priv(indio_dev);
> + struct i2c_client *client = chip->client;
> + int status;
> + unsigned long lval;
> +
> + if (kstrtoul(buf, 10, &lval))
> + return -EINVAL;
> +
> + mutex_lock(&chip->lock);
> + if (lval > 0x10000)
> + lval = 0xFFFF;
> + status = cm3218_write(client, CM3218_REG_ADDR_CMD, (u16)lval);
> + if (status < 0) {
> + mutex_unlock(&chip->lock);
> + dev_err(dev, "Error in setting CM3218_REG_ADDR_CMD\n");
> + return status;
> + }
> + mutex_unlock(&chip->lock);
> +
> + return count;
> +}
> +
> +/* status */
> +static ssize_t show_status(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct iio_dev *indio_dev = dev_get_drvdata(dev);
> + struct cm3218_chip *chip = iio_priv(indio_dev);
> + struct i2c_client *client = chip->client;
> + int status;
> +
> + status = cm3218_read(client, CM3218_REG_ADDR_STATUS);
> + if (status < 0) {
> + dev_err(dev, "Error in getting CM3218_REG_ADDR_STATUS\n");
> + return status;
> + }
> +
> + return sprintf(buf, "%u\n", status);
> +}
> +
> +#endif /* CM3218_DEBUG */
> +
> +/* Channel IO */
> +static int cm3218_write_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int val,
> + int val2,
> + long mask)
> +{
> + struct cm3218_chip *chip = iio_priv(indio_dev);
> + int ret = -EINVAL;
ret is not used?
> +
> + mutex_lock(&chip->lock);
> + if (mask == IIO_CHAN_INFO_CALIBSCALE && chan->type == IIO_LIGHT) {
> + chip->lensfactor = val;
> + ret = 0;
> + }
> + mutex_unlock(&chip->lock);
> +
> + return 0;
> +}
> +
> +static int cm3218_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val,
> + int *val2,
> + long mask)
> +{
> + int ret = -EINVAL;
> + struct cm3218_chip *chip = iio_priv(indio_dev);
> + struct i2c_client *client = chip->client;
> +
> + mutex_lock(&chip->lock);
> + if (chip->suspended) {
> + mutex_unlock(&chip->lock);
> + return -EBUSY;
> + }
> + switch (mask) {
> + case 0:
huh? this is not in the channels?
> + ret = cm3218_read_lux(client, val);
> + if (!ret)
> + ret = IIO_VAL_INT;
> + break;
> + case IIO_CHAN_INFO_CALIBSCALE:
> + *val = chip->lensfactor;
> + ret = IIO_VAL_INT_PLUS_MICRO;
> + break;
> + default:
> + break;
> + }
> + mutex_unlock(&chip->lock);
> + return ret;
> +}
> +
> +#define IIO_CHAN_INFO_SEPARATE_BIT(type) BIT(type*2 + 1)
> +#define IIO_CHAN_INFO_CALIBSCALE_SEPARATE_BIT \
> + IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_CALIBSCALE)
> +
> +static const struct iio_chan_spec cm3218_channels[] = {
> + {
> + .type = IIO_LIGHT,
> + .indexed = 1,
> + .channel = 0,
> + .info_mask = IIO_CHAN_INFO_CALIBSCALE_SEPARATE_BIT,
info_mask_separate was recently introduced
> + }
> +};
> +
> +static IIO_DEVICE_ATTR(illuminance0_input, S_IRUGO, show_lux, NULL, 0);
> +static IIO_DEVICE_ATTR(illuminance0_calibscale, S_IRUGO | S_IWUSR,
> + show_lensfactor, store_lensfactor, 0);
not needed; I think you just need the iio_chan_spec
> +#ifdef CM3218_DEBUG
> +static IIO_DEVICE_ATTR(cmd, S_IRUGO | S_IWUSR, show_cmd, store_cmd, 0);
> +static IIO_DEVICE_ATTR(status, S_IRUGO, show_status, NULL, 0);
> +#endif /* CM3218_DEBUG */
> +
> +#define CM3218_DEV_ATTR(name) (&iio_dev_attr_##name.dev_attr.attr)
> +#define CM3218_CONST_ATTR(name) (&iio_const_attr_##name.dev_attr.attr)
> +static struct attribute *cm3218_attributes[] = {
> + CM3218_DEV_ATTR(illuminance0_input),
> + CM3218_DEV_ATTR(illuminance0_calibscale),
> +#ifdef CM3218_DEBUG
> + CM3218_DEV_ATTR(cmd),
> + CM3218_DEV_ATTR(status),
> +#endif /* CM3218_DEBUG */
> + NULL
> +};
> +
> +static const struct attribute_group cm3218_group = {
> + .attrs = cm3218_attributes,
> +};
> +
> +static int cm3218_chip_init(struct i2c_client *client)
> +{
> + struct cm3218_chip *chip = iio_priv(i2c_get_clientdata(client));
> + int status, i;
> +
> + memset(chip->reg_cache, 0, sizeof(chip->reg_cache));
> +
> + for (i = 0; i < 5; i++) {
> + status = cm3218_write(client, CM3218_REG_ADDR_CMD,
> + CM3218_CMD_ALS_SD);
> + if (status >= 0)
> + break;
> + cm3218_read_ara(client);
> + }
> +
> + status = cm3218_write(client, CM3218_REG_ADDR_CMD, CM3218_DEFAULT_CMD);
> + if (status < 0) {
> + dev_err(&client->dev, "Init CM3218 CMD fails\n");
> + return status;
> + }
> +
> +
> + /* Clean interrupt status */
> + cm3218_read(client, CM3218_REG_ADDR_STATUS);
> +
> + return 0;
> +}
> +
> +static const struct iio_info cm3218_info = {
> + .attrs = &cm3218_group,
> + .driver_module = THIS_MODULE,
> + .read_raw = &cm3218_read_raw,
> + .write_raw = &cm3218_write_raw,
> +};
> +
> +static int cm3218_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + struct cm3218_chip *chip;
> + struct iio_dev *indio_dev;
> + int err;
> +
> + indio_dev = iio_device_alloc(sizeof(*chip));
> + if (indio_dev == NULL) {
> + dev_err(&client->dev, "iio allocation fails\n");
> + err = -ENOMEM;
> + goto exit;
maybe directly return -ENOMEM?
> + }
> + chip = iio_priv(indio_dev);
> + chip->client = client;
> + i2c_set_clientdata(client, indio_dev);
> +
> + mutex_init(&chip->lock);
> +
> + chip->lensfactor = 1000;
maybe some platform data, DT magic to allow passing the lens factor?
> + chip->suspended = false;
> +
> + err = cm3218_chip_init(client);
> + if (err)
> + goto exit_iio_free;
> +
> + indio_dev->info = &cm3218_info;
> + indio_dev->channels = cm3218_channels;
> + indio_dev->num_channels = ARRAY_SIZE(cm3218_channels);
> + indio_dev->name = id->name;
> + indio_dev->dev.parent = &client->dev;
> + indio_dev->modes = INDIO_DIRECT_MODE;
> + err = iio_device_register(indio_dev);
> + if (err) {
> + dev_err(&client->dev, "iio registration fails\n");
> + goto exit_iio_free;
> + }
> +
> + return 0;
> +exit_iio_free:
> + iio_device_free(indio_dev);
> +exit:
> + return err;
> +}
> +
> +static int cm3218_detect(struct i2c_client *client,
> + struct i2c_board_info *info)
> +{
> + struct i2c_adapter *adapter = client->adapter;
> + const char *name = NULL;
> +
> + cm3218_read_ara(client);
> +
> + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
> + return -ENODEV;
the driver needs WORD_DATA
the check is after read_ara (which only needs BYTE_DATA)
what is read_ara() fails
> +
> + name = "cm3218";
> + strlcpy(info->type, name, I2C_NAME_SIZE);
> +
> + return 0;
> +}
> +
> +static int cm3218_remove(struct i2c_client *client)
> +{
> + struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> + dev_dbg(&client->dev, "%s()\n", __func__);
> + iio_device_unregister(indio_dev);
> + iio_device_free(indio_dev);
> +
> + return 0;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int cm3218_suspend(struct device *dev)
> +{
> + struct cm3218_chip *chip = iio_priv(dev_get_drvdata(dev));
> +
> + mutex_lock(&chip->lock);
> +
> + /* Since this driver uses only polling commands, we are by default in
> + * auto shutdown (ie, power-down) mode.
> + * So we do not have much to do here.
> + */
> + chip->suspended = true;
> +
> + mutex_unlock(&chip->lock);
> + return 0;
> +}
> +
> +static int cm3218_resume(struct device *dev)
> +{
> + struct iio_dev *indio_dev = dev_get_drvdata(dev);
> + struct cm3218_chip *chip = iio_priv(indio_dev);
> + struct i2c_client *client = chip->client;
> + int err;
> +
> + mutex_lock(&chip->lock);
> +
> + err = cm3218_chip_init(client);
> + if (!err)
> + chip->suspended = false;
> +
> + mutex_unlock(&chip->lock);
> + return err;
> +}
> +
> +static SIMPLE_DEV_PM_OPS(cm3218_pm_ops, cm3218_suspend, cm3218_resume);
> +#define CM3218_PM_OPS (&cm3218_pm_ops)
> +#else
> +#define CM3218_PM_OPS NULL
> +#endif
> +
> +static const struct i2c_device_id cm3218_id[] = {
> + {"cm3218", 0},
> + {}
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, cm3218_id);
> +
> +static const struct of_device_id cm3218_of_match[] = {
> + { .compatible = "invn,cm3218", },
> + { },
> +};
> +MODULE_DEVICE_TABLE(of, cm3218_of_match);
> +
> +static struct i2c_driver cm3218_driver = {
> + .class = I2C_CLASS_HWMON,
> + .driver = {
> + .name = "cm3218",
> + .pm = CM3218_PM_OPS,
> + .owner = THIS_MODULE,
> + .of_match_table = cm3218_of_match,
> + },
> + .probe = cm3218_probe,
> + .remove = cm3218_remove,
> + .id_table = cm3218_id,
> + .detect = cm3218_detect,
> + .address_list = normal_i2c,
> +};
> +module_i2c_driver(cm3218_driver);
> +
> +MODULE_DESCRIPTION("CM3218 Ambient Light Sensor driver");
> +MODULE_LICENSE("GPL");
>
--
Peter Meerwald
+43-664-2444418 (mobile)
--
To unsubscribe from this list: send the line "unsubscribe linux-iio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
