From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ej1-f53.google.com (mail-ej1-f53.google.com [209.85.218.53]) (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 9F9A72459E5 for ; Mon, 12 Jan 2026 09:30:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.218.53 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768210242; cv=none; b=bzKJVyUfggiVqVJ+dm4TkWDg2T2sw40XGJ2kTATBkzlpwwunF6rr1wCJtvCrjjmzkvLpIJnb8BjzCCL4yALx9cKLDKsljHmRmLu8sJGpdUoWjxcbQDRN4360rebGJyFamnQi/LKT6urbtymk9pczNNZ/YJJgvRSDVBA2E9jn+BI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768210242; c=relaxed/simple; bh=GWV28/vmpmO8SPm3F91Gti98N5Hg36koBeIE519B3i8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=B5MjhvC55c94tntOo+NWn/DElYFioLtONHcEV2er9UDAIyUlDucgQlmeeKjNRdnUevtnSW1r+Ruo+9k+sXEAUN/QrtlWIJz6BMsCcO8YiD+yVf3AKqceGvcN6DU687W0+NoBTvwyHIR3y3cIGq7DtfNeC5GXHiXmibVJaMv/vos= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=tuxon.dev; spf=pass smtp.mailfrom=tuxon.dev; dkim=pass (2048-bit key) header.d=tuxon.dev header.i=@tuxon.dev header.b=OsUA9GSJ; arc=none smtp.client-ip=209.85.218.53 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=tuxon.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=tuxon.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=tuxon.dev header.i=@tuxon.dev header.b="OsUA9GSJ" Received: by mail-ej1-f53.google.com with SMTP id a640c23a62f3a-b8719994ba4so106482666b.1 for ; Mon, 12 Jan 2026 01:30:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tuxon.dev; s=google; t=1768210238; x=1768815038; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=lNLrzr3qkVx4OIY6GjV8r8rlvuM/wNc6aOYx08xVrrQ=; b=OsUA9GSJiQJnuR4akDZDQgEHpG3KntWMVfYqn/jnln94cFOp6IK2+zuCgsx5iITR4/ ZtK6Udk1c17cnG1DBmNhCtfDNk+RF1z364tVbEhTB96KEOIJ3BW0VVbexGPQQro+i2+m LSW2QP5LXqypZKOCB4t6ury7aazAFlbYbbAKlkMxeoU/MFouYgB6Q6RLcW68ccLUzeBg M/MtY62qG2RaFXw/fE0PcxEsu/BHBLU5Zy4yplijU4Vve3/UXAl5iBMGFue15j4sajSR P6j6UjFHspU1BQ3Vr8KRwjwjAfVGOkrkiuOvqEz62tpfMxF5f0rVqUCpmO6q4t988OHA /BHQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1768210238; x=1768815038; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=lNLrzr3qkVx4OIY6GjV8r8rlvuM/wNc6aOYx08xVrrQ=; b=Ft1OorLIzS7fMPBAko3l/YcnVRpv/p1pBSx7Oa4HsJkDoXoyd/WYjQCIug5gEfk2bd F7pDLOLXWgkndqdCAakMTbAPAuexA5ufAX0xDrarcfLLTWinmb2JPS3AoUbEMIUEuS5T T5a+9anladipBlMnJhI7lxZ7fqrCHYHCjgLP1XrHiieSQqXu9zpcxJxsvidnLo3U/G3v l66inV+c6EPEHt39HqPtM1EfjnWwYnays8+EkeytptneU4kTR2yprly06uUwKxWLwsgB GfeG9QELPDgwmT8s5VDtd3xFUgskjxixLjzELTEpDdXzPo2RaYqpbdp9u0rR2Ip2WVKC +niQ== X-Forwarded-Encrypted: i=1; AJvYcCXcvXldsGe8k1IQ1Qln6WZI/3Nujp3cEHjcx0Uk6/9vn9IWPN46A56mEzBCg1Ii+d3WqaTDBWKiFsCps/A=@vger.kernel.org X-Gm-Message-State: AOJu0YyGe82lAfza9thQ/XvFc/71eDaaW3wEkAkb8a1e81bKUoxPgLPc n68GV1KRQM5x52QNtG722W+ZlcHQ1zZKD77U3BFKDT/W1APzWWwEKMpe42R9xX17ajY= X-Gm-Gg: AY/fxX6QGoErH4N4+n1XiGGEkrQ9iqpU7rtqvlhaDSQTQioES97Mt0/7kJSH+zrYcFT EwkOoX6BSRX2FFz//5BBNbatM/OeUvO0azHokoBxyACA6BnTvDR/idMMaL2OhiDgMvalKQyA96K MEcljBNwgODmXLAgS2WhHQQluux65x9x47yrc/oKn9xz0CgiSOHI+l1QDfKJCcV7ESsjp2ZnYJb I9Lm+MYwJ1hZhVTqWV2IOt1EE6aLTkB41sfo/Lh2wN6Qjm5tzh+xCxIY+mlvpxkT6xZvZHfBw+/ UvTCMrtX/ImaMH9fknB9aKaT6MVurFjOfKcm16jXX6P9L8+v6J6lcHw7SaxPtBYI7dvbayMKA14 Q2PWrwh1ddGgsDldQpdyDGQrZv5gUjveY3NNW8fLz1WDnjGLKLHEfVnlWY/BVHsUzTIxXJTqMOM b4I42gaWkEtpeaDXettw== X-Google-Smtp-Source: AGHT+IE3jERyAgUMeyNFYUFeB+yy2mozpdQFjJ6f8BNz9krP4mlTPOQQ5ezMeogXcOrzxqj3jJR6fg== X-Received: by 2002:a17:906:f5a1:b0:b7a:72bd:ac65 with SMTP id a640c23a62f3a-b8444c3fc39mr1534919766b.9.1768210237758; Mon, 12 Jan 2026 01:30:37 -0800 (PST) Received: from [192.168.50.4] ([82.78.167.31]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-b844e46ee63sm1446817366b.15.2026.01.12.01.30.36 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 12 Jan 2026 01:30:37 -0800 (PST) Message-ID: <2ad40570-102e-448b-bf40-06af8ecdfca2@tuxon.dev> Date: Mon, 12 Jan 2026 11:30:35 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 3/4] dmaengine: sh: rz-dmac: Refactor runtime PM handling To: Tommaso Merciai , tomm.merciai@gmail.com Cc: linux-renesas-soc@vger.kernel.org, biju.das.jz@bp.renesas.com, Vinod Koul , Geert Uytterhoeven , Wolfram Sang , Fabrizio Castro , =?UTF-8?Q?Uwe_Kleine-K=C3=B6nig?= , dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org References: <20250905144427.1840684-1-tommaso.merciai.xr@bp.renesas.com> <20250905144427.1840684-4-tommaso.merciai.xr@bp.renesas.com> Content-Language: en-US From: Claudiu Beznea In-Reply-To: <20250905144427.1840684-4-tommaso.merciai.xr@bp.renesas.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi, Tommaso, On 9/5/25 17:44, Tommaso Merciai wrote: > Refactor runtime PM handling to ensure correct power management and prevent > resource leaks. Invoke pm_runtime_get_sync() when allocating DMA channel > resources and pm_runtime_put() when freeing them. Add pm_runtime_put() in > rz_dmac_probe() to balance the usage count during device initialization, > and remove the unnecessary pm_runtime_put() from rz_dmac_remove() to avoid > PM inconsistencies. > > Signed-off-by: Tommaso Merciai > --- > drivers/dma/sh/rz-dmac.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c > index 0bc11a6038383..4ab6076f5499e 100644 > --- a/drivers/dma/sh/rz-dmac.c > +++ b/drivers/dma/sh/rz-dmac.c > @@ -455,7 +455,7 @@ static int rz_dmac_alloc_chan_resources(struct dma_chan *chan) > if (!channel->descs_allocated) > return -ENOMEM; > > - return channel->descs_allocated; > + return pm_runtime_get_sync(chan->device->dev); This looks wrong to me as, rz_dmac_alloc_chan_resources() could be called from the following path: dma_request_chan() -> find_candidate() -> dma_chan_get() -> rz_dmac_alloc_chan_resources() With this, the runtime PM reference counter is incremented on dma_request_chan() calls, when DMA consumers request DMA channels, and remains different than zero until the DMA channel is put. But, on suspend path, the runtime PM reference counter is not touched even when there are DMA channels requested. Am I missing something? Thank you, Claudiu