Re: [PATCH v3 1/3] usb: misc: onboard-hub: support multiple power supplies - Greg Kroah-Hartman

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Benjamin Bara <bbara93@gmail.com>
Cc: Matthias Kaehlcke <mka@chromium.org>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Conor Dooley <conor+dt@kernel.org>,
	Benjamin Bara <benjamin.bara@skidata.com>,
	linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
	devicetree@vger.kernel.org
Subject: Re: [PATCH v3 1/3] usb: misc: onboard-hub: support multiple power supplies
Date: Wed, 21 Jun 2023 18:06:42 +0200	[thread overview]
Message-ID: <2023062102-booth-glorify-2b09@gregkh> (raw)
In-Reply-To: <20230620-hx3-v3-1-2acbc03ca949@skidata.com>

On Wed, Jun 21, 2023 at 05:58:30PM +0200, Benjamin Bara wrote:
> From: Benjamin Bara <benjamin.bara@skidata.com>
> 
> As some of the onboard hubs require multiple power supplies, provide the
> environment to support them.
> 
> Signed-off-by: Benjamin Bara <benjamin.bara@skidata.com>
> ---
> v3:
> - fix nits mentioned in v2
> 
> v2:
> - replace (err != 0) with (err)
> ---
>  drivers/usb/misc/onboard_usb_hub.c | 39 ++++++++++++++++++++++++++++++--------
>  drivers/usb/misc/onboard_usb_hub.h |  1 +
>  2 files changed, 32 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/usb/misc/onboard_usb_hub.c b/drivers/usb/misc/onboard_usb_hub.c
> index 12fc6eb67c3b..a56e712d3a45 100644
> --- a/drivers/usb/misc/onboard_usb_hub.c
> +++ b/drivers/usb/misc/onboard_usb_hub.c
> @@ -27,6 +27,13 @@
>  
>  #include "onboard_usb_hub.h"
>  
> +#define MAX_SUPPLIES 2

Why 2?

> +
> +static const char * const supply_names[] = {
> +	"vdd",
> +	"vdd2",
> +};

Do those names have anything to do with the number above?  If so, please
document it!

>  struct onboard_hub_pdata {
>  	unsigned long reset_us;		/* reset pulse width in us */
> +	unsigned int num_supplies;	/* number of supplies: 0 considered as 1 */

I can not understand that comment at all :(