From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f51.google.com (mail-wr1-f51.google.com [209.85.221.51]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4FCF21487F4 for ; Sat, 18 Oct 2025 14:16:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.51 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760796989; cv=none; b=u0b8QHzA7ZsqIuFGqcMoKzLJR76ZSiRifTDk/rXvmi1eawBMDw4+PvyCwtUc+XK9TsZ+ht75bcxrnl5JCIJ2+qvAPD7ZZwJy9JJlj54JOihNp+A2Oy17/vUlTJak/Ltf76J7vfYvgNjx770Hh10vZ/xmWXoNnl8O71gJD1CcDJA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760796989; c=relaxed/simple; bh=X29ameIskitCKG39iDo9fnFG74io4N0elFSW5JYWjCU=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=RphkRzbIF0QLGpazdAQ4ysebc7NdzkQcD/TmjaNd4wvXW4Mpk/QT/BN9ZTC/VvXZSl7MzmB44dQtXKorhbBKzsmCJt5z5Te52j12N9AQhpn7Hb++SqsPM1fCH+Zo4LSq4XENx/IWEuRT+WCOWQRdPO/Zvr2pwpzVa4QCPq3mPUY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=IvWGG/wU; arc=none smtp.client-ip=209.85.221.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="IvWGG/wU" Received: by mail-wr1-f51.google.com with SMTP id ffacd0b85a97d-42701b29a7eso1341130f8f.0 for ; Sat, 18 Oct 2025 07:16:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1760796986; x=1761401786; darn=vger.kernel.org; h=mime-version:user-agent:content-transfer-encoding:references :in-reply-to:date:cc:to:from:subject:message-id:from:to:cc:subject :date:message-id:reply-to; bh=IlCRwb6ZxMUe1+qjY84Z++qKGjm7fl4y3NpRzyLl6u0=; b=IvWGG/wUtI48CVMZIi9Os8g+nfjkPY39YS79IHWMLT0tVBRwPXOgf8LDfqH+LEcRJ5 tx76ayt/kII0DAvvry2RDzch4AdRaKXf6M786FkJR4ES6WADi4A7vhVLStCZTfJY9sxm /SmeQ7F9tMPrTyQKBtPMFxwstaJVZnzeVNzKbYWMAt9ZLLejxQt9IJDn/313AMjPZOsG vPaJFC1HrUgYEFvv2rckwnC6koMxbwMPbcGUWxLH+kPOkcNeiN/XRMO+5MoVtHDoPpUa Z1B9h/EhFHFWI6kyKyUjwq81JvdTW/YmM84hOgkOtaU5ra1S7DoVvrpyzDkjoXgvneDN SyCA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1760796986; x=1761401786; h=mime-version:user-agent:content-transfer-encoding:references :in-reply-to:date:cc:to:from:subject:message-id:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=IlCRwb6ZxMUe1+qjY84Z++qKGjm7fl4y3NpRzyLl6u0=; b=db61Qytk6Ejr8K1/DpcAeYwuJwWOAGquazxHVGD54oeWrPqrUlHT0F8fjwTcu8Vyj5 wRMc2XPe3AbVGENSfT8mlYTpPmMPh4FNzc88Jfp7HojfkoF4g71401/mh3KI5w2xYa9V X2b0f7rd1TqHT3itPCs1XA49XQUngMRjeex40SEXZ4SdnaiA0TdbKxsONyoQp/b4GyPI qLCApVHRaLnZPIrxx2QwgC0HFCw8CeqsYoWWCdvi1QpJYPRij2fqxIjc9gMYrvmwp0GJ C3uGphyKHNUDoX9KETKA+aMN478oXRcXt3hx02YTdbmeuQP7bGQdokme1y84sy22T5Z4 lH4A== X-Forwarded-Encrypted: i=1; AJvYcCWyPgXKnZCN405ytpG5oZjC/WpNiiKiTe+7fqr0krNL48JS0zlN/RGqUUyXX0aoxYlBONKBGR4ErYY=@vger.kernel.org X-Gm-Message-State: AOJu0YzEnT7ckenLFrFMuPVGrIvq2XA7uvahudprS+UVAFYxOefdjyBi KJXcNwt0Cx2i7Q2XV2QulgDiTFEnLXuQATmz1a4OHc8KkbroR1kK+eQw X-Gm-Gg: ASbGnctzwhD69/AvQFBv6OSAq2qfm8olNxHimCl1lA0AJZc6l27nA6ChsBCKYNKLI8a BLnSNuhNI90mLumg/5f517ZM4Kzadh0J/bHtGV/W1BYBfb42WNPCOn9pZTDNMfnAf3Dk4+hLnbj QmVP+Uga61xbqxU9HRBxyLP8GyiQ5GThv4BxOq75n/5ijdLgxapLF9PXxaAo7RlwyZufHX98HAN zfIfDDcS5wtelE0moIi0QcUp8O+LK0RGQnD6CVP4TAKVmQ98538SqRFP3WBNms1C6RczTHKbDQ0 uyrbdYI/zxybigPIoa4DiJ51OG+4jWSIzadxfXzo56pTfw84SkmYUUhqau30Crwz3zvCeF5ypH0 y/BXeX80TXwKRDb/CbDibAuWecJY0lzQzKj69lyhUTElAJt7EheSXs/Csl6GjibCMyYiwQXPD2h 05/0qEH7oy X-Google-Smtp-Source: AGHT+IG3AlPGTUhBjZicoKO2fafPrO3Ym6F/9eWov1dBZ28BCJY0XCxolDXbuHb3nvEg1oKZJQkcwQ== X-Received: by 2002:a05:6000:40dc:b0:414:fb6c:e369 with SMTP id ffacd0b85a97d-42704b3db2dmr4898244f8f.5.1760796985415; Sat, 18 Oct 2025 07:16:25 -0700 (PDT) Received: from [192.168.1.187] ([161.230.67.253]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-427e1be5d6csm5297975f8f.0.2025.10.18.07.16.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 18 Oct 2025 07:16:25 -0700 (PDT) Message-ID: Subject: Re: [PATCH v5 5/7] iio: adc: ad4030: Add SPI offload support From: Nuno =?ISO-8859-1?Q?S=E1?= To: Marcelo Schmitt Cc: Marcelo Schmitt , linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, jic23@kernel.org, michael.hennerich@analog.com, nuno.sa@analog.com, eblanc@baylibre.com, dlechner@baylibre.com, andy@kernel.org, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, corbet@lwn.net, Trevor Gamblin , Axel Haslam Date: Sat, 18 Oct 2025 15:16:57 +0100 In-Reply-To: References: <5e3a1d31f3cec340650e2e63db79903b78ab9a1f.camel@gmail.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.58.1 Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Fri, 2025-10-17 at 16:54 -0300, Marcelo Schmitt wrote: > On 10/17, Nuno S=C3=A1 wrote: > > On Tue, 2025-10-14 at 19:22 -0300, Marcelo Schmitt wrote: > > > AD4030 and similar ADCs can capture data at sample rates up to 2 mega > > > samples per second (MSPS). Not all SPI controllers are able to achiev= e > > > such > > > high throughputs and even when the controller is fast enough to run > > > transfers at the required speed, it may be costly to the CPU to handl= e > > > transfer data at such high sample rates. Add SPI offload support for > > > AD4030 > > > and similar ADCs to enable data capture at maximum sample rates. > > >=20 > > > Co-developed-by: Trevor Gamblin > > > Signed-off-by: Trevor Gamblin > > > Co-developed-by: Axel Haslam > > > Signed-off-by: Axel Haslam > > > Signed-off-by: Marcelo Schmitt > > > --- > >=20 > ... > > > +static int ad4030_offload_buffer_postenable(struct iio_dev *indio_de= v) > > > +{ > > > + struct ad4030_state *st =3D iio_priv(indio_dev); > > > + unsigned int reg_modes; > > > + int ret, ret2; > > > + > ... > > > + ret =3D spi_offload_trigger_enable(st->offload, st- > > > >offload_trigger, > > > + &st->offload_trigger_config); > > > + if (ret) > > > + goto out_pwm_disable; > > > + > > > + return 0; > > > + > > > +out_pwm_disable: > > > + pwm_disable(st->cnv_trigger); > > > +out_unoptimize: > > > + spi_unoptimize_message(&st->offload_msg); > > > +out_reset_mode: > > > + /* reenter register configuration mode */ > > > + ret2 =3D ad4030_enter_config_mode(st); > >=20 > > nit: if ret2 is not being used at all, maybe just > ret2 is logged on the error message below so I guess I'll keep it as it i= s. > >=20 > > if (ad4030_enter_config_mode(st)) > > =09 > > > + if (ret2) > > > + dev_err(&st->spi->dev, > > > + "couldn't reenter register configuration mode: > > > %d\n", > > > + ret2); > here we log the error code. We only reach it if reg access fails after > something on offload buffer enable have failed first. We cannot reuse ret= here > because we would be shadowing the original error code. Right :facepalm: