Re: [PATCH linux v3 1/3] drivers: w1: add hwmon support structures

[Guenter Roeck]

On Thu, Jul 13, 2017 at 02:06:47PM -0700, Jaghathiswari Rankappagounder Natarajan wrote:
> This patch has changes to w1.h/w1.c/w1_family.h generic files to
> add (optional) hwmon support structures.
> 
> Signed-off-by: Jaghathiswari Rankappagounder Natarajan <jaghu@xxxxxxxxxx>
> Acked-by: Evgeniy Polyakov <zbr@xxxxxxxxxxx>

Acked-by: Guenter Roeck <linux@xxxxxxxxxxxx>

> ---
> v2
> - made changes to support hwmon_device_register_with_info mentioned by Guenter.
> 
> v3
> - used IS_REACHABLE(CONFIG_HWMON)
> - removed hwmon device first before removing slave.
> 
>  drivers/w1/w1.c        | 18 +++++++++++++++++-
>  drivers/w1/w1.h        |  2 ++
>  drivers/w1/w1_family.h |  2 ++
>  3 files changed, 21 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c
> index e213c678bbfe..0e5423c1d31c 100644
> --- a/drivers/w1/w1.c
> +++ b/drivers/w1/w1.c
> @@ -32,6 +32,7 @@
>  #include <linux/sched.h>
>  #include <linux/kthread.h>
>  #include <linux/freezer.h>
> +#include <linux/hwmon.h>
> 
>  #include <linux/atomic.h>
> 
> @@ -659,9 +660,24 @@ static int w1_family_notify(unsigned long action, struct w1_slave *sl)
>  				return err;
>  			}
>  		}
> -
> +		if (IS_REACHABLE(CONFIG_HWMON) && fops->chip_info) {
> +			struct device *hwmon
> +				= hwmon_device_register_with_info(&sl->dev,
> +						"w1_slave_temp", sl,
> +						fops->chip_info,
> +						NULL);
> +			if (IS_ERR(hwmon)) {
> +				dev_warn(&sl->dev,
> +					 "could not create hwmon device\n");
> +			} else {
> +				sl->hwmon = hwmon;
> +			}
> +		}
>  		break;
>  	case BUS_NOTIFY_DEL_DEVICE:
> +		if (IS_REACHABLE(CONFIG_HWMON) && fops->chip_info
> +				&& sl->hwmon)

Nitpick: checkpatch prefers && to be in the previous line.

> +			hwmon_device_unregister(sl->hwmon);
>  		if (fops->remove_slave)
>  			sl->family->fops->remove_slave(sl);
>  		if (fops->groups)
> diff --git a/drivers/w1/w1.h b/drivers/w1/w1.h
> index 129895f562b0..74ef1a543856 100644
> --- a/drivers/w1/w1.h
> +++ b/drivers/w1/w1.h
> @@ -83,6 +83,7 @@ struct w1_reg_num
>   * @family: module for device family type
>   * @family_data: pointer for use by the family module
>   * @dev: kernel device identifier
> + * @hwmon: pointer to hwmon device
>   *
>   */
>  struct w1_slave
> @@ -99,6 +100,7 @@ struct w1_slave
>  	struct w1_family	*family;
>  	void			*family_data;
>  	struct device		dev;
> +	struct device		*hwmon;
>  };
> 
>  typedef void (*w1_slave_found_callback)(struct w1_master *, u64);
> diff --git a/drivers/w1/w1_family.h b/drivers/w1/w1_family.h
> index 10a7a0767187..9001851e1316 100644
> --- a/drivers/w1/w1_family.h
> +++ b/drivers/w1/w1_family.h
> @@ -55,12 +55,14 @@ struct w1_slave;
>   * @add_slave: add_slave
>   * @remove_slave: remove_slave
>   * @groups: sysfs group
> + * @chip_info: pointer to struct hwmon_chip_info
>   */
>  struct w1_family_ops
>  {
>  	int  (* add_slave)(struct w1_slave *);
>  	void (* remove_slave)(struct w1_slave *);
>  	const struct attribute_group **groups;
> +	const struct hwmon_chip_info *chip_info;
>  };
> 
>  /**
> --
> 2.13.2.932.g7449e964c-goog
>