Re: [PATCH 2/5] i3c: master: Move entdaa error suppression

From: Adrian Hunter <adrian.hunter@intel.com>
To: "Jorge Marques" <jorge.marques@analog.com>,
	"Alexandre Belloni" <alexandre.belloni@bootlin.com>,
	"Frank Li" <Frank.Li@nxp.com>,
	"Przemysław Gaj" <pgaj@cadence.com>
Cc: <linux-i3c@lists.infradead.org>, <linux-kernel@vger.kernel.org>,
	"Dan Carpenter" <dan.carpenter@linaro.org>,
	Jonathan Cameron <jic23@kernel.org>
Subject: Re: [PATCH 2/5] i3c: master: Move entdaa error suppression
Date: Tue, 10 Mar 2026 21:13:56 +0200	[thread overview]
Message-ID: <648bb51c-6c29-4412-adef-c1915b4f9c8f@intel.com> (raw)
In-Reply-To: <20260308-ad4062-positive-error-fix-v1-2-72d3c5290b4a@analog.com>

On 08/03/2026 18:47, Jorge Marques wrote:
> The CCC ENTDAA is invoked with i3c_master_entdaa_locked and yields
> error I3C_ERROR_M2 if there are no devices active on the bus.
> Some controllers may also yield if there are no more devices need an
> dynamic address, since the sequence do always end in a NACK.
> 
> Handle inside i3c_master_entdaa_locked, checking cmd->err directly.

Commit message has the same issues as patch 1

And the pertinent fact that there are only 2 call sites of
i3c_master_entdaa_locked() and both are dealt with.

> 
> Signed-off-by: Jorge Marques <jorge.marques@analog.com>
> ---
>  drivers/i3c/master.c                 | 7 +++++--
>  drivers/i3c/master/adi-i3c-master.c  | 3 +--
>  drivers/i3c/master/i3c-master-cdns.c | 2 +-
>  3 files changed, 7 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
> index 31822fd5ffde..ce1898345810 100644
> --- a/drivers/i3c/master.c
> +++ b/drivers/i3c/master.c
> @@ -1036,8 +1036,7 @@ static int i3c_master_rstdaa_locked(struct i3c_master_controller *master,
>   *
>   * This function must be called with the bus lock held in write mode.
>   *
> - * Return: 0 in case of success, a positive I3C error code if the error is
> - * one of the official Mx error codes, and a negative error code otherwise.
> + * Return: 0 in case of success, or a negative error code otherwise.

That comment change seems premature.  Mx (x!=2) error codes are propagated
until patch 4

>   */
>  int i3c_master_entdaa_locked(struct i3c_master_controller *master)
>  {
> @@ -1050,6 +1049,10 @@ int i3c_master_entdaa_locked(struct i3c_master_controller *master)
>  	ret = i3c_master_send_ccc_cmd_locked(master, &cmd);
>  	i3c_ccc_cmd_dest_cleanup(&dest);
>  
> +	/* No active devices need an address. */
> +	if (ret && cmd.err == I3C_ERROR_M2)
> +		ret = 0;
> +
>  	return ret;
>  }
>  EXPORT_SYMBOL_GPL(i3c_master_entdaa_locked);
> diff --git a/drivers/i3c/master/adi-i3c-master.c b/drivers/i3c/master/adi-i3c-master.c
> index 6616f751075a..fb9a48830446 100644
> --- a/drivers/i3c/master/adi-i3c-master.c
> +++ b/drivers/i3c/master/adi-i3c-master.c
> @@ -655,8 +655,7 @@ static int adi_i3c_master_do_daa(struct i3c_master_controller *m)
>  
>  	writel(irq_mask, master->regs + REG_IRQ_MASK);
>  
> -	/* DAA always finishes with CE2_ERROR or NACK_RESP */
> -	if (ret && ret != I3C_ERROR_M2)
> +	if (ret)
>  		return ret;
>  
>  	/* Add I3C devices discovered */
> diff --git a/drivers/i3c/master/i3c-master-cdns.c b/drivers/i3c/master/i3c-master-cdns.c
> index b78aebf6b2ca..5cfec6761494 100644
> --- a/drivers/i3c/master/i3c-master-cdns.c
> +++ b/drivers/i3c/master/i3c-master-cdns.c
> @@ -1143,7 +1143,7 @@ static int cdns_i3c_master_do_daa(struct i3c_master_controller *m)
>  	}
>  
>  	ret = i3c_master_entdaa_locked(&master->base);
> -	if (ret && ret != I3C_ERROR_M2)
> +	if (ret)
>  		return ret;
>  
>  	newdevs = readl(master->regs + DEVS_CTRL) & DEVS_CTRL_DEVS_ACTIVE_MASK;
> 

-- 
linux-i3c mailing list
linux-i3c@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-i3c