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Date: Mon, 6 May 2024 10:54:51 +0200
From: Miquel Raynal <miquel.raynal@bootlin.com>
To: Frank Li <Frank.Li@nxp.com>
Cc: Conor Culhane <conor.culhane@silvaco.com>, Alexandre Belloni
 <alexandre.belloni@bootlin.com>, linux-i3c@lists.infradead.org (moderated
 list:SILVACO I3C DUAL-ROLE MASTER), linux-kernel@vger.kernel.org (open
 list), imx@lists.linux.dev
Subject: Re: [PATCH 1/2] i3c: master: svc: change ENXIO to EAGAIN when IBI
 occurs during start frame
Message-ID: <20240506105451.26e40778@xps-13>
In-Reply-To: <20240424190030.857632-1-Frank.Li@nxp.com>
References: <20240424190030.857632-1-Frank.Li@nxp.com>
Organization: Bootlin
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Hi Frank,

Frank.Li@nxp.com wrote on Wed, 24 Apr 2024 15:00:29 -0400:

> svc_i3c_master_xfer() returns error ENXIO if an In-Band Interrupt (IBI)
> occurs when the host starts the frame.
>=20
> Change error code to EAGAIN to inform the client driver that this
> situation has occurred and to try again sometime later.

This changes slightly the user API, but feels legitimate at the same
time. Maybe a comment somewhere in the i3c headers to clarify this
possibility might be welcome?

> Fixes: 5e5e3c92e748 ("i3c: master: svc: fix wrong data return when IBI ha=
ppen during start frame")
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
>  drivers/i3c/master/svc-i3c-master.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>=20
> diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc=
-i3c-master.c
> index 5ee4db68988e2..a2298ab460a37 100644
> --- a/drivers/i3c/master/svc-i3c-master.c
> +++ b/drivers/i3c/master/svc-i3c-master.c
> @@ -1080,7 +1080,7 @@ static int svc_i3c_master_xfer(struct svc_i3c_maste=
r *master,
>  	 * and yield the above events handler.
>  	 */
>  	if (SVC_I3C_MSTATUS_IBIWON(reg)) {
> -		ret =3D -ENXIO;
> +		ret =3D -EAGAIN;
>  		*actual_len =3D 0;
>  		goto emit_stop;
>  	}


Thanks,
Miqu=C3=A8l