On Thu, Jan 09, 2025 at 01:21:10PM +0100, Wolfram Sang wrote:
> More and more I2C client drivers use debugfs entries and currently they
> need to manage a subdir for their files on their own. This means
> inconsistent naming for these subdirs and they are scattered all over
> the debugfs-tree as well. Not to mention the duplicated code.
>
> Let the I2C core provide and maintain a proper directory per client.
>
> Note: It was considered to save the additional pointer in 'struct
> i2c_client' and only provide a subdir when requested via a helper
> function. When sketching this approach, more and more corner cases
> appeared, though, so the current solution with its simple and unabiguous
> code was chosen.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> ---
> drivers/i2c/i2c-core-base.c | 4 ++++
> include/linux/i2c.h | 1 +
> 2 files changed, 5 insertions(+)
>
> diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
> index b072030a9105..00f171ebc01f 100644
> --- a/drivers/i2c/i2c-core-base.c
> +++ b/drivers/i2c/i2c-core-base.c
> @@ -1015,6 +1015,8 @@ i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *inf
> if (status)
> goto out_remove_swnode;
>
> + client->debugfs = debugfs_create_dir(dev_name(&client->dev), adap->debugfs);
> +
> dev_dbg(&adap->dev, "client [%s] registered with bus id %s\n",
> client->name, dev_name(&client->dev));
>
> @@ -1058,6 +1060,8 @@ void i2c_unregister_device(struct i2c_client *client)
>
> if (ACPI_COMPANION(&client->dev))
> acpi_device_clear_enumerated(ACPI_COMPANION(&client->dev));
> +
> + debugfs_remove_recursive(client->debugfs);
> device_remove_software_node(&client->dev);
> device_unregister(&client->dev);
> }
> diff --git a/include/linux/i2c.h b/include/linux/i2c.h
> index 66fb3d6cf686..36de788dc7fe 100644
> --- a/include/linux/i2c.h
> +++ b/include/linux/i2c.h
> @@ -347,6 +347,7 @@ struct i2c_client {
> i2c_slave_cb_t slave_cb; /* callback for slave mode */
> #endif
> void *devres_group_id; /* ID of probe devres group */
> + struct dentry *debugfs; /* per-client debugfs dir */
> };
> #define to_i2c_client(d) container_of(d, struct i2c_client, dev)
>
> --
> 2.45.2
>
