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Date: Tue, 7 May 2024 10:03:19 +0200
From: Miquel Raynal <miquel.raynal@bootlin.com>
To: Frank Li <Frank.Li@nxp.com>
Cc: alexandre.belloni@bootlin.com, conor.culhane@silvaco.com,
 imx@lists.linux.dev, linux-i3c@lists.infradead.org,
 linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/3] i3c: Add comment for -EAGAIN in
 i3c_device_do_priv_xfers()
Message-ID: <20240507100319.04d8039f@xps-13>
In-Reply-To: <20240506164009.21375-1-Frank.Li@nxp.com>
References: <20240506164009.21375-1-Frank.Li@nxp.com>
Organization: Bootlin
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Hi Frank,

Frank.Li@nxp.com wrote on Mon,  6 May 2024 12:40:07 -0400:

> In accordance with I3C spec ver 1.1.1 09-Jun-2021, section: 5.1.2.2.3, if
> a target requests hot join (HJ), In-Band Interrupt (IBI), or controller
> role request (CRR) during the emission of an I3C address in
> i3c_device_do_priv_xfers(), the target may win bus arbitration. In such
> cases, it is imperative to notify the I3C client driver and retry
> i3c_device_do_priv_xfers() after some delay.
>=20
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
>=20
> Notes:
>     Change from v1 to v2
>     - new patch
>=20
>  drivers/i3c/device.c | 4 ++++
>  1 file changed, 4 insertions(+)
>=20
> diff --git a/drivers/i3c/device.c b/drivers/i3c/device.c
> index 1a6a8703dbc3a..b04a55a1337d4 100644
> --- a/drivers/i3c/device.c
> +++ b/drivers/i3c/device.c
> @@ -27,6 +27,10 @@
>   * This function can sleep and thus cannot be called in atomic context.
>   *
>   * Return: 0 in case of success, a negative error core otherwise.
> + *	   -EAGAIN: controller lost address arbitration. Target
> + *		    (IBI, HJ or controller role request) win the bus. Client
> + *		    driver need resend this 'xfers' some time later.

			 needs to resend the 'xfers'

> + *		    See I3C spec ver 1.1.1 09-Jun-2021. Section: 5.1.2.2.3.
>   */
>  int i3c_device_do_priv_xfers(struct i3c_device *dev,
>  			     struct i3c_priv_xfer *xfers,


With this little nit,

Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>


Thanks,
Miqu=C3=A8l