From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793470888; b=jatLje/oDBW5AAvxRtSF94Hez12R9ccLpp5qsGZJhxKwnWKV+Li4mBHdjorov33RQAiX ztt2jg6JK8UKblXf1nPiIgvL0s+MhMqpuKqiWpXJLU2wsuLz18lk2ZArlsNFAx4GYm5++ A5Hun1fU6yGnkGBgBF5Sr5Z8qXGy9SKMiyBdEQToLf1SBk/C+O8FGG3Ep7CniHeYZcUKp HKteochWkJLdD5k9BejL6GqtqRQvxElbDxO9/0oY9a4kDDYssLqTLzH11lGZxvC+HX28f a2Xzbn/D5hvC9LOWYtsLBsUy1/WNDFi1RSe7D8UMAqD7K9+DDsyF5TcDAdFemF/1U+g== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793470888; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:X-Developer-Signature: X-Developer-Key:Content-Transfer-Encoding; bh=lHKFRctLDfXlCv2OU3bCsqyyCRbSpNPu6FlORAWwFwE=; b=UI4kfa3xjgDuUC56w2XLG7y12+SWDOZVlIiAv53T4GTy6DV8kL3P7T/byqN7BJ/AJwo+ IYM3vp/V1RmvGmJ9JJOewGaubL+xTEvMqVE6anfVLl4aaqVyR45FKJO49JzKtAJeLkjEz hFGi6KxVND/PxccFgFWruB5Cp1J3Y1cUToGpCG8eYLRlgEy0GvEF6Hy0Nc4XSc1GExziI KySi6OKBpampuzc5+QzoQpTmMnR5uwKl0x6jV7rd+xsYqlfRO1EuJ+NvFzynKHrN5M1b9 37ihAKiWIraTFOoRN3puFlWEiO4KWwtOl0p5T6yvb2OdX0YP1jmWol074Sct4QQ/LYg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=hTiVZ46j; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 49C18606A31A; Sat, 31 Oct 2026 18:21:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=hTiVZ46j Received: by smtp.kernel.org (Postfix) with ESMTPSA id B9FFF1F000C1; Sat, 31 Oct 2026 18:21:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793470887; bh=lHKFRctLDfXlCv2OU3bCsqyyCRbSpNPu6FlORAWwFwE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=hTiVZ46jpxyLejVCQJV/JU+oCM33Z8pBI4QxA0ZJJUrQRNV/2jfoDvmS4Bz/D4zr7 /1ZFLS8neKlXUNFNy3GkEl4V41ArIFXF9PX+y40Ucv6ynGIDV1LjB3buv0RU/A2Nlv LCPtpLDllFhQZVZCkeRBFhGTru/QY1O/0DBZnayzBTN5+GNhs9IFid/0GiaYEtmC40 lYPKayUGmUtcHb/LtBlTTjUR9XmFlLTclXORuPBq2UAxDTSc2wRtzY3Y80R1njO6BV liAvZbOsgi99Z3PrY87WENo/G0TFHijqkvWwlnRoctYGRRp0KTS+D0qQfJ1SsfcKS2 mljHYemnl3+Pg== From: William Breathitt Gray To: Biju Das Cc: William Breathitt Gray , Li Youhong , "linux-iio@vger.kernel.org" , "linux-renesas-soc@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Cosmin-Gabriel Tanislav , Li Youhong , "stable@vger.kernel.org" Subject: Re: [PATCH v2] counter: rz-mtu3-cnt: put runtime PM ref if counter init fails Date: Sat, 31 Oct 2026 14:21:19 -0400 Message-ID: <20261031182120.3646747-1-wbg@kernel.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: References: X-Mailing-List: linux-iio@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2694; i=wbg@kernel.org; h=from:subject; bh=4jOGApQctKuARm0QUpYj59awkb17qYceby5349anA7c=; b=owGbwMvMwCW21SPs1D4hZW3G02pJDFnPDLs+zMzxqVJ8LFWoosmlav7pRaBJWszVQw6Vyz9Os z7E6/W7o5SFQYyLQVZMkaXX/OzdB5dUNX68mL8NZg4rE8gQBi5OAZjI1kMM/5O+vn3F+Xch75LC 9Wt49nzYfkH9RmJBr/WLxTkMv/xOTrzCyPCO8Xn31u3aV/MFP9xKmbJ4s8qL8wIvXgaWNXN8Fd5 gwMAKAA== X-Developer-Key: i=wbg@kernel.org; a=openpgp; fpr=8D37CDDDE0D22528F8E89FB6B54856CABE12232B Content-Transfer-Encoding: 8bit On Sat, Oct 31, 2026 at 04:34:32PM +0000, Biju Das wrote: > Hi William Breathitt Gray, > > Thanks for the feedback. > > > -----Original Message----- > > From: William Breathitt Gray > > Sent: 31 October 2026 16:29 > > Subject: Re: [PATCH v2] counter: rz-mtu3-cnt: put runtime PM ref if counter init fails > > > > On Sat, Oct 31, 2026 at 10:28:13PM +0800, Li Youhong wrote: > > > From: Li Youhong > > > > > > Counter enable takes a runtime PM reference before initialization but > > > only puts it on disable. Drop the reference if initialization fails. > > > > > > Fixes: 0be8907359df ("counter: Add Renesas RZ/G2L MTU3a counter > > > driver") > > > Cc: stable@vger.kernel.org > > > Reviewed-by: Cosmin Tanislav > > > Signed-off-by: Li Youhong > > > --- > > > v2: > > > - Add Cc: stable@vger.kernel.org. > > > - v1: > > > https://lore.kernel.org/all/20261008020506.211566-1-dayou5941@163.com/ > > > > > > drivers/counter/rz-mtu3-cnt.c | 7 +++++-- > > > 1 file changed, 5 insertions(+), 2 deletions(-) > > > > > > diff --git a/drivers/counter/rz-mtu3-cnt.c > > > b/drivers/counter/rz-mtu3-cnt.c index 7bfb6979193c..61fbeb122851 > > > 100644 > > > --- a/drivers/counter/rz-mtu3-cnt.c > > > +++ b/drivers/counter/rz-mtu3-cnt.c > > > @@ -506,8 +506,11 @@ static int rz_mtu3_count_enable_write(struct counter_device *counter, > > > if (enable) { > > > pm_runtime_get_sync(counter->parent); > > > ret = rz_mtu3_initialize_counter(counter, count->id); > > > - if (ret == 0) > > > - priv->count_is_enabled[count->id] = true; > > > + if (ret < 0) { > > > + pm_runtime_put(counter->parent); > > > + goto exit; > > > + } > > > + priv->count_is_enabled[count->id] = true; > > > } else { > > > rz_mtu3_terminate_counter(counter, count->id); > > > priv->count_is_enabled[count->id] = false; > > > -- > > > 2.25.1 > > > V> > > > This patch seems similar to another we're considering for ti-eqep.[^1] In that patch, runtime PM is > > managed via devm which allows us to remove the explicit PM unwind on failures and have them implicitly > > handled when the device resource is released. Should we use the same approach for rz-mtu-cnt? > > Here we save power, clock is turned on/off during counter enable/disable. > On TI case, they enable it during the probe which unnecessarily waste power. > Even disable case, the clock is on. > > Cheers, > Biju I suppose you are right. There is no need to keep the clocks powered if the counter is disabled because we are no longer counting. William Breathitt Gray.