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References: <20240403-ucsi-reset-delay-v2-1-244c175825a4@chromium.org>
In-Reply-To: <20240403-ucsi-reset-delay-v2-1-244c175825a4@chromium.org>
From: Prashant Malani <pmalani@chromium.org>
Date: Wed, 3 Apr 2024 15:22:09 -0700
Message-ID: <CACeCKafbnsnvk1pbghf_eRN+RV3_7Q46POm2hQxW+gSt8a5z5w@mail.gmail.com>
Subject: Re: [PATCH v2] usb: typec: ucsi: Wait 20ms before reading CCI after a reset
To: Pavan Holla <pholla@chromium.org>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>, 
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>, linux-usb@vger.kernel.org, 
	linux-kernel@vger.kernel.org, 
	Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
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Hi Pavan,

On Wed, Apr 3, 2024 at 10:57=E2=80=AFAM Pavan Holla <pholla@chromium.org> w=
rote:
>
> The PPM might take time to process a reset. Allow 20ms for the reset to
> be processed before reading the CCI.
>
> Signed-off-by: Pavan Holla <pholla@chromium.org>
> ---
> The PPM might take time to process a reset and set the CCI. Give the PPM
> 20ms to update it's CCI.
>
> Based on the discussion in v1, this should not slow down existing
> implementations because they would not set any bits in the CCI after a re=
set,
> and would take a 20ms delay to read the CCI anyway. This change just make=
s the
> delay explicit, and reduces a CCI read. Based on the spec, the PPM has
> 10ms to set busy, so, 20ms seems like a reasonable delay before we read
> the CCI.

The above information is helpful context, and should be included
in the commit message, otherwise it will get lost on patch application.

With that, feel free to add:
Reviewed-by: Prashant Malani <pmalani@chromium.org>

BR,

-Prashant