Re: [PATCH] iio/adc/ltc2497: Add IIO to HWMON hooks

[Jonathan Cameron <jic23@kernel.org>]

On Tue, 27 Jun 2017 11:59:56 -0700
Gaurav Gupta <gauragup@cisco.com> wrote:

> Add missing hooks in the LTC2497 IIO driver to allow hwmon mapping.
Technically this adds the handling needed for any
consumer driver. I'll modify the title and description to
reflect that.   It'll certainly work for hwmon though.

Applied to the togreg branch of iio.git and initially pushed out
as testing for the autobuilders to play with it.

Thanks,

Jonathan
> 
> Signed-off-by: Gaurav Gupta <gauragup@cisco.com>
> ---
>  drivers/iio/adc/ltc2497.c | 54 ++++++++++++++++++++++++++++++-----------------
>  1 file changed, 35 insertions(+), 19 deletions(-)
> 
> diff --git a/drivers/iio/adc/ltc2497.c b/drivers/iio/adc/ltc2497.c
> index 2691b10..5bf8011 100644
> --- a/drivers/iio/adc/ltc2497.c
> +++ b/drivers/iio/adc/ltc2497.c
> @@ -11,6 +11,7 @@
>  #include <linux/delay.h>
>  #include <linux/i2c.h>
>  #include <linux/iio/iio.h>
> +#include <linux/iio/driver.h>
>  #include <linux/iio/sysfs.h>
>  #include <linux/module.h>
>  #include <linux/of.h>
> @@ -127,13 +128,14 @@ static int ltc2497_read_raw(struct iio_dev *indio_dev,
>  	}
>  }
>  
> -#define LTC2497_CHAN(_chan, _addr) { \
> +#define LTC2497_CHAN(_chan, _addr, _ds_name) { \
>  	.type = IIO_VOLTAGE, \
>  	.indexed = 1, \
>  	.channel = (_chan), \
>  	.address = (_addr | (_chan / 2) | ((_chan & 1) ? LTC2497_SIGN : 0)), \
>  	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
>  	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
> +	.datasheet_name = (_ds_name), \
>  }
>  
>  #define LTC2497_CHAN_DIFF(_chan, _addr) { \
> @@ -148,22 +150,22 @@ static int ltc2497_read_raw(struct iio_dev *indio_dev,
>  }
>  
>  static const struct iio_chan_spec ltc2497_channel[] = {
> -	LTC2497_CHAN(0, LTC2497_SGL),
> -	LTC2497_CHAN(1, LTC2497_SGL),
> -	LTC2497_CHAN(2, LTC2497_SGL),
> -	LTC2497_CHAN(3, LTC2497_SGL),
> -	LTC2497_CHAN(4, LTC2497_SGL),
> -	LTC2497_CHAN(5, LTC2497_SGL),
> -	LTC2497_CHAN(6, LTC2497_SGL),
> -	LTC2497_CHAN(7, LTC2497_SGL),
> -	LTC2497_CHAN(8, LTC2497_SGL),
> -	LTC2497_CHAN(9, LTC2497_SGL),
> -	LTC2497_CHAN(10, LTC2497_SGL),
> -	LTC2497_CHAN(11, LTC2497_SGL),
> -	LTC2497_CHAN(12, LTC2497_SGL),
> -	LTC2497_CHAN(13, LTC2497_SGL),
> -	LTC2497_CHAN(14, LTC2497_SGL),
> -	LTC2497_CHAN(15, LTC2497_SGL),
> +	LTC2497_CHAN(0, LTC2497_SGL, "CH0"),
> +	LTC2497_CHAN(1, LTC2497_SGL, "CH1"),
> +	LTC2497_CHAN(2, LTC2497_SGL, "CH2"),
> +	LTC2497_CHAN(3, LTC2497_SGL, "CH3"),
> +	LTC2497_CHAN(4, LTC2497_SGL, "CH4"),
> +	LTC2497_CHAN(5, LTC2497_SGL, "CH5"),
> +	LTC2497_CHAN(6, LTC2497_SGL, "CH6"),
> +	LTC2497_CHAN(7, LTC2497_SGL, "CH7"),
> +	LTC2497_CHAN(8, LTC2497_SGL, "CH8"),
> +	LTC2497_CHAN(9, LTC2497_SGL, "CH9"),
> +	LTC2497_CHAN(10, LTC2497_SGL, "CH10"),
> +	LTC2497_CHAN(11, LTC2497_SGL, "CH11"),
> +	LTC2497_CHAN(12, LTC2497_SGL, "CH12"),
> +	LTC2497_CHAN(13, LTC2497_SGL, "CH13"),
> +	LTC2497_CHAN(14, LTC2497_SGL, "CH14"),
> +	LTC2497_CHAN(15, LTC2497_SGL, "CH15"),
>  	LTC2497_CHAN_DIFF(0, LTC2497_DIFF),
>  	LTC2497_CHAN_DIFF(1, LTC2497_DIFF),
>  	LTC2497_CHAN_DIFF(2, LTC2497_DIFF),
> @@ -192,6 +194,7 @@ static int ltc2497_probe(struct i2c_client *client,
>  {
>  	struct iio_dev *indio_dev;
>  	struct ltc2497_st *st;
> +	struct iio_map *plat_data;
>  	int ret;
>  
>  	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
> @@ -221,19 +224,31 @@ static int ltc2497_probe(struct i2c_client *client,
>  	if (ret < 0)
>  		return ret;
>  
> +	if (client->dev.platform_data) {
> +		plat_data = ((struct iio_map *)client->dev.platform_data);
> +		ret = iio_map_array_register(indio_dev, plat_data);
> +		if (ret) {
> +			dev_err(&indio_dev->dev, "iio map err: %d\n", ret);
> +			goto err_regulator_disable;
> +		}
> +	}
> +
>  	ret = i2c_smbus_write_byte(st->client, LTC2497_CONFIG_DEFAULT);
>  	if (ret < 0)
> -		goto err_regulator_disable;
> +		goto err_array_unregister;
>  
>  	st->addr_prev = LTC2497_CONFIG_DEFAULT;
>  	st->time_prev = ktime_get();
>  
>  	ret = iio_device_register(indio_dev);
>  	if (ret < 0)
> -		goto err_regulator_disable;
> +		goto err_array_unregister;
>  
>  	return 0;
>  
> +err_array_unregister:
> +	iio_map_array_unregister(indio_dev);
> +
>  err_regulator_disable:
>  	regulator_disable(st->ref);
>  
> @@ -245,6 +260,7 @@ static int ltc2497_remove(struct i2c_client *client)
>  	struct iio_dev *indio_dev = i2c_get_clientdata(client);
>  	struct ltc2497_st *st = iio_priv(indio_dev);
>  
> +	iio_map_array_unregister(indio_dev);
>  	iio_device_unregister(indio_dev);
>  	regulator_disable(st->ref);
>