From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from hall.aurel32.net (hall.aurel32.net [195.154.113.88]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7898A2D6E64; Thu, 6 Nov 2025 05:34:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=195.154.113.88 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762407281; cv=none; b=nvxwOW5qZnu2U0iOrL6cv1Vlo0KWTTxc1gY6MoivcTq2oInYKx6YNgFkC7aG8EyzpKyrqB2oalu7lEVIsiknF0qpn85Jaznl5sPnctkxHSxZiYEdXNkzSmO6gkQg9LLzqvXrW5zB5nFgk8C3WXqM8WV1ueBrqiJN2Eau/RTl3FQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762407281; c=relaxed/simple; bh=zd+PmBIZBaaUuaEnv0alnOBIu2wIiccyM0pqoAtdJsg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=KkBUFoRZQbm3Egt2IAyi4+HLJ6YTSvekzSAQ/EG4IFhg1AOu6ebbpP01Hk+YZNdZxzhx8gmxGXpsiywuyrTPyQ+W+yl3o8FXUI3Ybp7YzzqiADJySxApyG2jYscYQFL0W8op7y46sxSIKckOmV0l80tv/uNQKPpPwFw/Vfq8CH4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=aurel32.net; spf=pass smtp.mailfrom=aurel32.net; dkim=pass (2048-bit key) header.d=aurel32.net header.i=@aurel32.net header.b=s1C6BXEr; arc=none smtp.client-ip=195.154.113.88 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=aurel32.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=aurel32.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=aurel32.net header.i=@aurel32.net header.b="s1C6BXEr" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=aurel32.net ; s=202004.hall; h=In-Reply-To:Content-Type:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Content-Transfer-Encoding:From:Reply-To: Subject:Content-ID:Content-Description:X-Debbugs-Cc; bh=acX4/obtZc57euus2wjyzRPxFvGCI3+UJzV/4FNBXzk=; b=s1C6BXEr5oJ1X/hOzOEhUfuaB5 PBHVKBjGhz8gKMjiYNB+Dg48gQWnPEY4iLHhvBzl58ZOdSaNl/T+vH+MBHhl1h29a85uLcAq8wgPN D0mR1W/k5TRhk9GQ6ZldtCTZ5R4QhvnjCrD6NbBns+QugXZBaSGVOedo+WOfgsH9E3WXBw4qWTuS8 ca0IrnP89cA5iyBcwp/DgbgDS5Z+nk4dOCEqE7xuP64UOBv1+F30XzP47X4pSkyxw+gektOryglGt wsXV576Lr9NCtkj2OlIriw3BmmHf5UJJquHQYSFjQB4N+XC3Pf9uCZwoelOZj2zpiVN2waRzyJAtP CDgTiJnA==; Received: from [2a01:e34:ec5d:a741:1ee1:92ff:feb4:5ec0] (helo=ohm.rr44.fr) by hall.aurel32.net with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1vGsdf-0000000B370-2CgX; Thu, 06 Nov 2025 06:34:27 +0100 Date: Thu, 6 Nov 2025 06:34:26 +0100 From: Aurelien Jarno To: Troy Mitchell Cc: Andi Shyti , Yixun Lan , Alex Elder , Michael Opdenacker , Troy Mitchell , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, spacemit@lists.linux.dev Subject: Re: [PATCH] i2c: spacemit: fix detect issue Message-ID: Mail-Followup-To: Troy Mitchell , Andi Shyti , Yixun Lan , Alex Elder , Michael Opdenacker , Troy Mitchell , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, spacemit@lists.linux.dev References: <20251103-fix-k1-detect-failure-v1-1-bb07a8d7de7c@linux.spacemit.com> <12878F9DA586AA19+aQv0bKwLTzw_kJOq@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <12878F9DA586AA19+aQv0bKwLTzw_kJOq@kernel.org> User-Agent: Mutt/2.2.13 (2024-03-09) Hi, On 2025-11-06 09:05, Troy Mitchell wrote: > On Wed, Nov 05, 2025 at 11:44:00PM +0100, Aurelien Jarno wrote: > > Hi, > > > > On 2025-11-03 15:06, Troy Mitchell wrote: > [...] > > > if (i2c->status & (SPACEMIT_SR_BED | SPACEMIT_SR_ALD)) { > > > spacemit_i2c_reset(i2c); > > > - return -EAGAIN; > > > + if (i2c->status & SPACEMIT_SR_ALD) > > > + return -EAGAIN; > > > } > > > > This makes the resulting code, while correct, complex to understand as > > it is now two really different errors, as you explained well in the > > commit message. > > > > I therefore suggest to organize the code as: > > > > /* Arbitration Loss Detected */ > > if (i2c->status & SPACEMIT_SR_ALD) { > > spacemit_i2c_reset(i2c); > > return -EAGAIN; > > } > > > > /* Bus Error No ACK/NAK */ > > if (i2c->status & SPACEMIT_SR_BED) { > > spacemit_i2c_reset(i2c); > > } > Thanks. I'll fix it in the next version. > > > > > > > return i2c->status & SPACEMIT_SR_ACKNAK ? -ENXIO : -EIO; > > > @@ -491,6 +492,8 @@ static int spacemit_i2c_xfer(struct i2c_adapter *adapt, struct i2c_msg *msgs, in > > > > > > spacemit_i2c_init(i2c); > > > > > > + spacemit_i2c_clear_int_status(i2c, SPACEMIT_I2C_INT_STATUS_MASK); > > > + > > > > This sounds good to start the transfer with a clean interrupt state. I > > just wonder if it should be moved to spacemit_i2c_init(), ie where the > > corresponding interrupts are enabled. > Uh, We can move it actually. But is it essentail? For me ensuring that the interrupt status is in a clean state after enabling the interrupt is part of the initialization. Furthermore if spacemit_i2c_init() has to be called from another place, it's very likely that it's also needed to get interrupt status in a clean state. Regards Aurelien -- Aurelien Jarno GPG: 4096R/1DDD8C9B aurelien@aurel32.net http://aurel32.net