From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=198.175.65.19 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792962535; b=iT5VEHdwuvLf8GzD5FUHKlFxxdBz+FKb+25RZ4oJqPIHtcBt0V8eqH6WUosTUg71yCO/ 1U51ho67C1iGlJaqPiDoEfqSB7Rw/p/OxVBYpdT/fT8WaT5/3WU5HASuiXJ2uu6cme4Ec KLoF0reSLtFVgKNI/aqhysPdegmqzF+ZDxId3CYv1qR2nH+y7pBvjFwile5PORh4Xx8pu qEPKKHvJQxGhZpHsJGk5A+aGU9GclzK4AtbhSxRQc7iOjzLjIXU1RcsYwdrNmeW80tPw2 Gfio5CyKSQKb2kDRI8pEp8Tag2fLB0ZcBgUXOg6gfOnXAroE1pBpDWijUE72yNUTvdQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792962535; h=DMARC-Filter:DKIM-Signature:X-CSE-ConnectionGUID:X-CSE-MsgGUID: X-IronPort-AV:X-IronPort-AV:Received:X-CSE-ConnectionGUID: X-CSE-MsgGUID:X-ExtLoop1:X-IronPort-AV:Received:Date:From:To:Cc: Subject:Message-ID:References:MIME-Version:Content-Type: Content-Disposition:In-Reply-To:Organization; bh=0hTonDNrvazpNb68heoGRE1WEbqb6H4Cq+6nx5Aw3Tk=; b=VhOsUYJUaVPBYz/M63TeXTV2akBp4y4xcDPKqKAZdujglw0WShcFEKOSCQiREl7CcGKO wuLFzGfssdn3IOp3mAAbK870sfwrf6uVZ0cb2f1tEfeKhOhvovsr7+SLM4MsZEY6LQDG1 5NMms9d1/FGQkR49rAORLUoYS+1daUdnvLt30L8TTx4L8ZYOmLsozAcrBYwOdNSszDSaz MTcbkMdmWriOEpNZjzipEBIR0Ob4wZW22D4ci7bAOvOPmnZ63wcleRs9m1z5268D+7bZN 9UMAey28ASPBberFzJnVVKe8YxGZSc27fCyOp6HxdV7kdYNq4tiO7jZEzPlzBeaFX5g== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=F5ft2uBt; arc=none smtp.remote-ip=198.175.65.19 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.19]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B847D606A31A; Sun, 25 Oct 2026 21:08:54 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org B847D606A31A Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=F5ft2uBt DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1792962535; x=1824498535; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=tPktMJC8ZUhXLZKzTryijfniAEadKhAOZYoSqFz3s/s=; b=F5ft2uBtoShifCkCyofc0daTdvzoUV7aXQqZwI0n9Ca9u/h5ZaGc6eSp 1YxhagGnZZmLzNxH+XoP84sVRq2o/5+boP+9LUqw9koSf5ukAkJpniMjJ hAjpKcBumcwQnvlw9s6kJ1LA5Ai9SGRpIehYWv5ctfigIf+0TDsEqkxjo fhW+SSTCE9dFPbVi8T19mPfUQGWhen4uv8ptIO3Hn7Hq1RwFlibs/IW4t oPM5d3IsfBLU8snuVz49Mbz12tV7p3QKwVzH0AYN16evFBYYQvkoL4PJS F9XjJ4MnryWp1g5fVBswjZdCt1ra2/sDPNL2MIO6cEN45cUsssZIp3dGA w==; X-CSE-ConnectionGUID: A6TiOpIbTEyzNxjtotw2UA== X-CSE-MsgGUID: 3bSSpmQdQnmCTXksUxHFIA== X-IronPort-AV: E=McAfee;i="6800,10657,11946"; a="1658313" X-IronPort-AV: E=Sophos;i="6.27,178,1787036400"; d="scan'208";a="1658313" Received: from fmviesa013.fm.intel.com ([10.60.135.153]) by orvoesa111.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Oct 2026 14:08:54 -0700 X-CSE-ConnectionGUID: TUC48Du8THyPchNmdbrQTA== X-CSE-MsgGUID: k2wGBJzmT7OpB91T3QBeKA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,178,1787036400"; d="scan'208";a="5932743" Received: from hrotuna-mobl2.ger.corp.intel.com (HELO localhost) ([10.245.245.10]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Oct 2026 14:08:52 -0700 Date: Sun, 25 Oct 2026 23:08:50 +0200 From: Andy Shevchenko To: "Baek Kyu, Kim" Cc: Jonathan Cameron , linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, David Lechner , Nuno =?iso-8859-1?Q?S=E1?= , Andy Shevchenko Subject: Re: [PATCH] iio: dac: mcp4725: Update the cached DAC value only on success Message-ID: References: <20261025141351.33554-1-pocj8ur4in@gmail.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261025141351.33554-1-pocj8ur4in@gmail.com> Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo On Sun, Oct 25, 2026 at 11:13:51PM +0900, Baek Kyu, Kim wrote: > mcp4725_write_raw() updates dac_value even if mcp4725_set_value() rejects > the requested value or reports an I2C transfer error. After writing 1000, > a rejected write of 4096 returns -EINVAL without an I2C transfer, but > out_voltage0_raw reports 4096. A later powerdown exit sends 00 00 instead > of the 03 e8 frame for the last successful value. The EEPROM store path > uses the same cache. > > Return the setter error before updating dac_value. This keeps the last > successful software value for readback, powerdown exit and EEPROM writes. Does it need a Fixes tag? > Signed-off-by: Baek Kyu, Kim -- With Best Regards, Andy Shevchenko