From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ej1-f46.google.com (mail-ej1-f46.google.com [209.85.218.46]) (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 5CA102144D7; Wed, 19 Feb 2025 17:28:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.218.46 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739986127; cv=none; b=nv29lZebVoujQhHZlM5P6mTFSmJ6C261C16piiN404TyH3QeO/lu44zcK7MWI5c/7CuzxA82RFapM012A/RjTQEpIYJbnxw1eKZjR4CO+XHXct5RiDA2tmxV3o/J86SNFCIuhPiqbXDFx+sDOaLfNEmtFYHnBYVzDFVUFX6hm7I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739986127; c=relaxed/simple; bh=KeHrbq9+/KLUuc3o4CRJqpjQacIlopX9KXp8AMmZgpk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=WQvte8rGbwqmXOiebGC76wko8ObsUfyTysM6YzKqLpHbNsnXNoQLNuXoJXYWjGg5oRjGXAJX/ky7UbHUjZrsnJaUx2INV02zQnO+ILo4soFYg8aBbm7HiKfROsAJ7pjPMGRsgSAqBhhne+/ODdFdwZAxX+u37wF89dx35YpAk+4= 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=gD8UzGxH; arc=none smtp.client-ip=209.85.218.46 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="gD8UzGxH" Received: by mail-ej1-f46.google.com with SMTP id a640c23a62f3a-abbc38adeb1so13870966b.1; Wed, 19 Feb 2025 09:28:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1739986123; x=1740590923; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=oJvk3PzO8UJcQqRvZYSLjrxNTJFPtwx8YpqkUT72Kbo=; b=gD8UzGxH3B+/K6WcJhXfXNoL+WnEi7+M3TSTtwsitytCRbW7HuuTt9CGL31hfe3Nau 89StpOx7xQkdy9cj6wfNK0tof1I9nTXUAzVwVpgM1NFuNuXv/Fl8YZeorDg0yMghpJ3v x4j1gpOcSkHuewEoPDRbnAAUFRdmUIvVETYQlJrkwbbWcXTGfEwbAr4psbsudAZaHRpT zHFhK0ojsT4MSSHYZ7uFwOgXh2ieoBrG7eWipjJBCWsN3UwsiFKg7TooDXSG86/qfghs 34I3AsO70qRrr2nPlyBI0OB9ViKmvjEIQebfaZTw2f0/5wVysJDA2keu7UrIfuC41ssJ Efmg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1739986123; x=1740590923; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=oJvk3PzO8UJcQqRvZYSLjrxNTJFPtwx8YpqkUT72Kbo=; b=jDP0IsDlLhR3BcVDEHBP/Jpw2X6TB+b2+crCfBm7+INgMPF9RxTTOAgLV9dWF12OIb XsA5ICo+Msx2aAbvJeGS4XD6HaxCSt25/7jbjwAE7ROS5zncI0lReJxpmZjtnRtIzxgf UA2DWkS1SGp45Tp/jnpHhE4fbCfvlEVxb4KZK22alsNTicgFgAAL5e5av29a55arZwLc DC2K/zCe5dgirbGtUyATRPe2PZrgPGFHFTyK7GyFKDum0RRc/JRRoNUaC9nH18Ps/riL IpbGZN77CsiwOlpKxLudR5ZLyxXUsy1ICeTeT7vIs48hu5/++FIO+IkJJonY/WKQ+Plj mk1g== X-Forwarded-Encrypted: i=1; AJvYcCVjkN0SltzWwgNPJ4W514PhhK2Cn8s+sCMQLBTtt1nEiA1EcAWwzM8m4SD12+7Sn0dogvvmPJj+CesuiLE=@vger.kernel.org, AJvYcCXS7rnKJuQtEsL23yeGou6/u2r5TvoUihDZaNSf4zpf167F5KavL+b0M90Slv4HpbSHTNZV+TI2@vger.kernel.org X-Gm-Message-State: AOJu0YxDTA7Fk1XQ4tM/iA1J8AReLIFmRTZfsRHvIQ9h0ZZRuuxojgBM COlQsabXmheNivGYX8SogM0S5wpFuNLTdJN7ZdluBLA93APL5mOW X-Gm-Gg: ASbGnct6x22L1gSKskr3/gMDW54aw/KF0pkYDGnpDAXMAx+Ns7+vmsZrfDKOicGE0UK uOr4F3eesO4BwVsPe4ObrreS4GywJCZpedf2pjK7WuFKXW7skHYPhiVDEKAdQmtgq2vjX+DJFnP cStUtbJscrcxWUOakGg6xuUViIYx0vz8p7uE1y6FmBcpOph8gd9rUeiRNpyECbiws8ItsIvY2Z8 5cwqkcZ7Bv0PVm306jLD/kCX6gTCTXKxn5USndpeF1J3mw3MkP+1WMUxVuA/Y3ODxUa3bNamxrI 9e0kNe/7j9rmTL8/Bw== X-Google-Smtp-Source: AGHT+IFNf4fdkqEc+24rmFUK+6430USqOj02thhBl42cygp+gf745aITOrh4dTndmQTFda58zcNp5A== X-Received: by 2002:a17:906:2718:b0:abb:ebfe:d5eb with SMTP id a640c23a62f3a-abbebfed7admr25133666b.18.1739986123228; Wed, 19 Feb 2025 09:28:43 -0800 (PST) Received: from eichest-laptop ([178.197.206.181]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-abbab339807sm496018966b.162.2025.02.19.09.28.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 19 Feb 2025 09:28:42 -0800 (PST) Date: Wed, 19 Feb 2025 18:28:40 +0100 From: Stefan Eichenberger To: Dimitri Fedrau Cc: Andrew Lunn , Heiner Kallweit , Russell King , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Niklas =?iso-8859-1?Q?S=F6derlund?= , Gregor Herburger , Geert Uytterhoeven , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] net: phy: marvell-88q2xxx: Prevent reading temperature with asserted reset Message-ID: References: <20250218-marvell-88q2xxx-hwmon-enable-at-probe-v1-0-999a304c8a11@gmail.com> <20250218-marvell-88q2xxx-hwmon-enable-at-probe-v1-2-999a304c8a11@gmail.com> <20250219105458.GD3888@debian> Precedence: bulk X-Mailing-List: netdev@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: <20250219105458.GD3888@debian> Hi Dimitri, On Wed, Feb 19, 2025 at 11:54:58AM +0100, Dimitri Fedrau wrote: > Hi Stefan, > > Am Wed, Feb 19, 2025 at 07:29:49AM +0100 schrieb Stefan Eichenberger: > > Hi Dimitri, > > > > On Tue, Feb 18, 2025 at 07:33:10PM +0100, Dimitri Fedrau wrote: > > > If the PHYs reset is asserted it returns 0xffff for any read operation. > > > Prevent reading the temperature in this case and return with an I/O error. > > > Write operations are ignored by the device. > > > > > > Fixes: a197004cf3c2 ("net: phy: marvell-88q2xxx: Fix temperature measurement with reset-gpios") > > > Signed-off-by: Dimitri Fedrau > > > --- > > > drivers/net/phy/marvell-88q2xxx.c | 6 ++++++ > > > 1 file changed, 6 insertions(+) > > > > > > diff --git a/drivers/net/phy/marvell-88q2xxx.c b/drivers/net/phy/marvell-88q2xxx.c > > > index 30d71bfc365597d77c34c48f05390db9d63c4af4..c1ae27057ee34feacb31c2e3c40b2b1769596408 100644 > > > --- a/drivers/net/phy/marvell-88q2xxx.c > > > +++ b/drivers/net/phy/marvell-88q2xxx.c > > > @@ -647,6 +647,12 @@ static int mv88q2xxx_hwmon_read(struct device *dev, > > > struct phy_device *phydev = dev_get_drvdata(dev); > > > int ret; > > > > > > + /* If the PHYs reset is asserted it returns 0xffff for any read > > > + * operation. Return with an I/O error in this case. > > > + */ > > > + if (phydev->mdio.reset_state == 1) > > > + return -EIO; > > > + > > > switch (attr) { > > > case hwmon_temp_input: > > > ret = phy_read_mmd(phydev, MDIO_MMD_PCS, > > > > > > > It makes sense to me. However, aren't most phys that allow reading > > sensors over MDIO affected by this issue? I couldn't find anything > > similar, are they ignoring that use-case? > > > Yes, you are right, but only if the PHYs hard reset is controlled with > "reset-gpios" or similar. I didn't find anything about it too. Okay, I see. Maybe at one point it can be generalized, but for now this sounds good to me. Just address the inputs from Andrew. Regards, Stefan