Re: [PATCH] clk: eyeq: Use devm_platform_ioremap_resource()

["Théo Lebrun" <theo.lebrun@bootlin.com>]

Hello Benoît,

On Fri Sep 11, 2026 at 1:48 PM CEST, Benoît Monin wrote:
> Convert eqc_probe() from the open-coded platform_get_resource() +
> ioremap() sequence to devm_platform_ioremap_resource(). Besides less
> code, this requests the memory region so the OLB registers are properly
> reserved in the iomem_resource tree.
>
> Move devm_platform_ioremap_resource() before checking for device match
> data, so OLBs bound without match data also get their memory region
> mapped and reserved.
>
> Add an entry for mobileye,eyeq6h-central-olb without match data: its
> clocks are all registered by the early init and it has no auxiliary
> devices, so probe() now reserves its region and stops there.
>
> Suggested-by: Vladimir Kondratiev <vladimir.kondratiev@mobileye.com>
> Signed-off-by: Benoît Monin <benoit.monin@bootlin.com>
> ---
>  drivers/clk/clk-eyeq.c | 16 ++++++----------
>  1 file changed, 6 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/clk/clk-eyeq.c b/drivers/clk/clk-eyeq.c
> index cf37feccc734..bb680283b6f2 100644
> --- a/drivers/clk/clk-eyeq.c
> +++ b/drivers/clk/clk-eyeq.c
> @@ -513,21 +513,16 @@ static int eqc_probe(struct platform_device *pdev)
>  	const struct eqc_match_data *data;
>  	struct clk_hw_onecell_data *cells;
>  	unsigned int i, clk_count;
> -	struct resource *res;
>  	void __iomem *base;
>  	int ret;
>  
> +	base = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(base))
> +		return PTR_ERR(base);
> +
>  	data = device_get_match_data(dev);
>  	if (!data)
> -		return 0; /* No clocks nor auxdevs, we are done. */
> -
> -	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> -	if (!res)
> -		return -ENODEV;
> -
> -	base = ioremap(res->start, resource_size(res));
> -	if (!base)
> -		return -ENOMEM;
> +		return 0; /* Early only clocks, stop here but keep resource reserved */

Technically it is "early only clocks OR auxdevs", as is seen in.
Not that it matters much.

static const struct eqc_match_data eqc_eyeq6h_west_match_data = {
   .reset_auxdev_name = "reset_west",
};

>  
>  	/* Init optional auxiliary devices. */
>  	eqc_auxdev_create_optional(dev, base, data->reset_auxdev_name);
> @@ -1175,6 +1170,7 @@ static const struct of_device_id eqc_match_table[] = {
>  	{ .compatible = "mobileye,eyeq5-olb", .data = &eqc_eyeq5_match_data },
>  	{ .compatible = "mobileye,eyeq6l-olb", .data = &eqc_eyeq6l_match_data },
>  	{ .compatible = "mobileye,eyeq6lplus-olb", .data = &eqc_eyeq6lplus_match_data },
> +	{ .compatible = "mobileye,eyeq6h-central-olb" /* no data, early only */ },
>  	{ .compatible = "mobileye,eyeq6h-west-olb", .data = &eqc_eyeq6h_west_match_data },
>  	{ .compatible = "mobileye,eyeq6h-east-olb", .data = &eqc_eyeq6h_east_match_data },
>  	{ .compatible = "mobileye,eyeq6h-south-olb", .data = &eqc_eyeq6h_south_match_data },

I can confirm this is the way to go! The open-coded
platform_get_resource() + ioremap() sequence is heritage from how the
series used to look during its first revisions.

Reviewed-by: Théo Lebrun <theo.lebrun@bootlin.com>

Thanks,

--
Théo Lebrun, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com