Re: [PATCH v3 08/23] ata: libahci_platform: Add function returning a clock-handle by id

[Hannes Reinecke <hare@xxxxxxx>]

On 5/12/22 01:17, Serge Semin wrote:
> Since all the clocks are retrieved by the method
> ahci_platform_get_resources() there is no need for the LLD (glue) drivers
> to be looking for some particular of them in the kernel clocks table
> again. Instead we suggest to add a simple method returning a
> device-specific clock with passed connection ID if it is managed to be
> found. Otherwise the function will return NULL. Thus the glue-drivers
> won't need to either manually touching the hpriv->clks array or calling
> clk_get()-friends. The AHCI platform drivers will be able to use the new
> function right after the ahci_platform_get_resources() method invocation
> and up to the device removal.
>
> Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>
>
> ---
>
> Changelog v2:
> - Fix some grammar mistakes in the method description.
> ---
>   drivers/ata/libahci_platform.c | 27 +++++++++++++++++++++++++++
>   include/linux/ahci_platform.h  |  3 +++
>   2 files changed, 30 insertions(+)
>
> diff --git a/drivers/ata/libahci_platform.c b/drivers/ata/libahci_platform.c
> index 3cff86c225fd..7ff6626fd569 100644
> --- a/drivers/ata/libahci_platform.c
> +++ b/drivers/ata/libahci_platform.c
> @@ -94,6 +94,33 @@ void ahci_platform_disable_phys(struct ahci_host_priv *hpriv)
>   }
>   EXPORT_SYMBOL_GPL(ahci_platform_disable_phys);
>   
> +/**
> + * ahci_platform_find_clk - Find platform clock
> + * @hpriv: host private area to store config values
> + * @con_id: clock connection ID
> + *
> + * This function returns a pointer to the clock descriptor of the clock with
> + * the passed ID.
> + *
> + * RETURNS:
> + * Pointer to the clock descriptor on success otherwise NULL
> + */
> +struct clk *ahci_platform_find_clk(struct ahci_host_priv *hpriv, const char *con_id)
> +{
> +	struct clk *clk = NULL;
> +	int i;
> +
> +	for (i = 0; i < hpriv->n_clks; i++) {
> +		if (!strcmp(hpriv->clks[i].id, con_id)) {
> +			clk = hpriv->clks[i].clk;
> +			break;
> +		}
> +	}
> +
> +	return clk;
> +}
> +EXPORT_SYMBOL_GPL(ahci_platform_find_clk);
> +
>   /**
>    * ahci_platform_enable_clks - Enable platform clocks
>    * @hpriv: host private area to store config values
> diff --git a/include/linux/ahci_platform.h b/include/linux/ahci_platform.h
> index 49e5383d4222..fd964e6a68d6 100644
> --- a/include/linux/ahci_platform.h
> +++ b/include/linux/ahci_platform.h
> @@ -13,6 +13,7 @@
>   
>   #include <linux/compiler.h>
>   
> +struct clk;
>   struct device;
>   struct ata_port_info;
>   struct ahci_host_priv;
> @@ -21,6 +22,8 @@ struct scsi_host_template;
>   
>   int ahci_platform_enable_phys(struct ahci_host_priv *hpriv);
>   void ahci_platform_disable_phys(struct ahci_host_priv *hpriv);
> +struct clk *
> +ahci_platform_find_clk(struct ahci_host_priv *hpriv, const char *con_id);
>   int ahci_platform_enable_clks(struct ahci_host_priv *hpriv);
>   void ahci_platform_disable_clks(struct ahci_host_priv *hpriv);
>   int ahci_platform_enable_regulators(struct ahci_host_priv *hpriv);

Where is this function being used?

Cheers,

Hannes
--
Dr. Hannes Reinecke		           Kernel Storage Architect
hare@xxxxxxx			                  +49 911 74053 688
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