Re: [PATCH v3 14/16] phy: Add notify_speed callback

[Kishon Vijay Abraham I <kishon@ti.com>]

Hi,

On Wednesday 20 December 2017 02:11 PM, Manu Gautam wrote:
> Hi
> 
> 
> On 12/20/2017 12:47 PM, Kishon Vijay Abraham I wrote:
>> Hi,
>>
> [snip]
>>>> Why not use a notification mechanism instead of adding new APIs in phy-core.
>>>> This will only bloat phy-core with APIs for a particular platform.
>>> Do you mean notifier_chains ?
>>> When we have multiple instances of USB PHYs then notifier chains are not
>>> of much help. For any platform glue or PHY driver it will be very difficult to
>>> figure out if notification received for speed was for same phy/bus or a
>>> different one.
>>> Using PHY callbacks looked more elegant to me. Additionally PHY drivers
>>> can also use this info decide power management policy e.g. if speed is
>>> INVALID then it means PHY is not in a session and it can enter deepest
>>> low power state.
>>> Additionally if you prefer set_speed name over notify_speed then I am
>>> ok with that as well so that it sounds more generic.
>> I'd prefer adding modes in enum phy_mode according to speed and using phy_set_mode.
> 
> yeah, that also seems good idea. How about something like this:
> 
> --- a/include/linux/phy/phy.h
> +++ b/include/linux/phy/phy.h
> @@ -23,12 +23,16 @@
>  struct phy;
>  
>  enum phy_mode {
> -	PHY_MODE_INVALID,
> -	PHY_MODE_USB_HOST,
> -	PHY_MODE_USB_DEVICE,
> -	PHY_MODE_USB_OTG,
> -	PHY_MODE_SGMII,
> -	PHY_MODE_10GKR,
> +	PHY_MODE_INVALID	= 0,
> +	PHY_MODE_USB_HOST	= BIT(0),
> +	PHY_MODE_USB_DEVICE	= BIT(1),
> +	PHY_MODE_USB_OTG,	= BIT(2),
> +	PHY_MODE_SGMII		= BIT(3),
> +	PHY_MODE_10GKR		= BIT(4),
> +	PHY_MODE_USB_LS		= BIT(5),
> +	PHY_MODE_USB_FS		= BIT(6),
> +	PHY_MODE_USB_HS		= BIT(7),
> +	PHY_MODE_USB_SS		= BIT(8),
>  };
> 
> 
> This way I don't need to duplicate USB speed enums for host/device or otg modes.

no.. let's keep enum. It's lot more cleaner IMO.

Thanks
Kishon