Re: [PATCH v3 2/2] Input: cros-ec-keyb - Expose function row physical map to userspace

[Dmitry Torokhov]

Hi Philip,

On Mon, Jan 04, 2021 at 06:22:34PM -0800, Philip Chen wrote:
> The top-row keys in a keyboard usually have dual functionalities.
> E.g. A function key "F1" is also an action key "Browser back".
> 
> Therefore, when an application receives an action key code from
> a top-row key press, the application needs to know how to correlate
> the action key code with the function key code and do the conversion
> whenever necessary.
> 
> Since the userpace already knows the key scanlines (row/column)
> associated with a received key code. Essentially, the userspace only
> needs a mapping between the key row/column and the matching physical
> location in the top row.
> 
> This patch enhances the cros-ec-keyb driver to create such a mapping
> and expose it to userspace in the form of a function-row-physmap
> attribute. The attribute would be a space separated ordered list of
> row/column codes, for the keys in the function row, in a left-to-right
> order.
> 
> The attribute will only be present when the device has a custom design
> for the top-row keys.
> 
> Signed-off-by: Philip Chen <philipchen@xxxxxxxxxxxx>
> ---
> 
> Changes in v3:
> - parse `function-row-physmap` from DT earlier, when we probe
>   cros_ec_keyb, and then store the extracted info in struct cros_ec_keyb.

Thank you for making the changes, much appreciated. Let's wait a bit to
see if Rob has any issues with this.

...

>  static int cros_ec_keyb_probe(struct platform_device *pdev)
>  {
>  	struct cros_ec_device *ec = dev_get_drvdata(pdev->dev.parent);
> @@ -617,6 +690,12 @@ static int cros_ec_keyb_probe(struct platform_device *pdev)
>  		return err;
>  	}
>  
> +	err = sysfs_create_group(&dev->kobj, &cros_ec_keyb_attr_group);
> +	if (err) {
> +		dev_err(dev, "failed to create attributes. err=%d\n", err);
> +		return err;
> +	}

Let's use devm_device_add_group() so that we do not need to remove it
manually in cros_ec_keyb_remove().

Thanks.

-- 
Dmitry