From mboxrd@z Thu Jan  1 00:00:00 1970
From: kishon@ti.com (Kishon Vijay Abraham I)
Date: Wed, 21 Nov 2018 15:59:43 +0530
Subject: [PATCH v2 8/9] phy: Add Cadence D-PHY support
In-Reply-To: <20181121101121.7rhe2hz2mnmc72cu@flea>
References: <cover.c2c2ae47383b9dbbdee6b69cafdd7391c06dde4f.1541516029.git-series.maxime.ripard@bootlin.com>
 <4ec9e47fb5aa9794f69a8e75a04108055094c056.1541516029.git-series.maxime.ripard@bootlin.com>
 <5f5bcc06-51b2-d565-56a0-083c66c1f01a@ti.com>
 <8536050b-40ab-1ec4-d325-e59bb3a92e73@ti.com>
 <20181121101121.7rhe2hz2mnmc72cu@flea>
Message-ID: <20c0fd85-95f6-9849-c10b-998a1e0f527d@ti.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

Hi Maxime,

On 21/11/18 3:41 PM, Maxime Ripard wrote:
> Hi Kishon,
> 
> On Tue, Nov 20, 2018 at 11:02:34AM +0530, Kishon Vijay Abraham I wrote:
>>>> +static int cdns_dphy_config_from_opts(struct phy *phy,
>>>> +				      struct phy_configure_opts_mipi_dphy *opts,
>>>> +				      struct cdns_dphy_cfg *cfg)
>>>> +{
>>>> +	struct cdns_dphy *dphy = phy_get_drvdata(phy);
>>>> +	unsigned int dsi_hfp_ext = 0;
>>>> +	int ret;
>>>> +
>>>> +	ret = phy_mipi_dphy_config_validate(opts);
>>>> +	if (ret)
>>>> +		return ret;
>>>> +
>>>> +	ret = cdns_dsi_get_dphy_pll_cfg(dphy, cfg,
>>>> +					opts, &dsi_hfp_ext);
>>>> +	if (ret)
>>>> +		return ret;
>>>> +
>>>> +	opts->wakeup = cdns_dphy_get_wakeup_time_ns(dphy);
>>
>> Is the wakeup populated here used by the consumer driver?
> 
> It's supposed to, if it can yes.

But I guess right now it's not using. I'm thinking the usefulness of validate
callback (only from this series point of view). Why should a consumer driver
invoke validate if it doesn't intend to configure the PHY?

The 3 steps required are
	* The consumer driver gets the default config
	* The consumer driver changes some of the configuration and
	* The consumer driver invokes phy configure callback.

phy_configure anyways can validate the config before actually configuring the phy.

Thanks
Kishon