From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4047DC5472D for ; Tue, 27 Aug 2024 01:34:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:References:Cc:To:Subject:From:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=/Q9mCEfT7guHVPvwR6ja5s0FAEOaseOBjw07BJH8nVo=; b=h1bBktbK1TCY/Wti3zg7em39WU dBNjr+V4jwBdY3LjADUZRmR5PtjRKENNZjrPSgHOJYMH0fyiSPc5ri/nPVi9unpOggMN89oyyxjWX /zNBdYqn7X1J3AfDCufowaKQoIHPGkRSuGhGohJ1w4TkSbTwqFHN9Ks3KP+fujDOsNpOfDpHizoi5 2KlLnDjrbQRBdRiue8j5GcsSE+GULk8agQnmocMFAwqaN4v+Qvc8gbwhH9oU5L9f1t3z4WEZdVBxU AhKLnY+/Og6xKC8EBlgKnvfKubROwEBRdc9zgf1HvPkGx7SQCMafCemurCWajxPXKWofE2n0s29D1 K7DiqRYA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sil6O-00000009Km3-2yvh; Tue, 27 Aug 2024 01:34:32 +0000 Received: from mail-m118217.qiye.163.com ([115.236.118.217]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sil5D-00000009KVu-00XZ; Tue, 27 Aug 2024 01:33:30 +0000 DKIM-Signature: a=rsa-sha256; b=YwcnEvCBSXSDD0L2/VPndhPM3BAC608LHVmbCaY2FgrSLmixGTDXK16c9laZL3Vc9zhBA79CGcacJ3buJ5kKH47oW87YRniMjjfMXheaeN6kQfiFnypvIHorTL204omol7FROzdb9AFMeP+YNmhX5PuAXuKxR4hhOKr8HF0+6qE=; c=relaxed/relaxed; s=default; d=rock-chips.com; v=1; bh=/Q9mCEfT7guHVPvwR6ja5s0FAEOaseOBjw07BJH8nVo=; h=date:mime-version:subject:message-id:from; Received: from [172.16.33.28] (unknown [58.22.7.114]) by smtp.qiye.163.com (Hmail) with ESMTPA id 0C70C6E01B6; Tue, 27 Aug 2024 09:32:50 +0800 (CST) Message-ID: <27302919-5bcd-4bcd-bdad-02aa48e628e9@rock-chips.com> Date: Tue, 27 Aug 2024 09:32:52 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird From: Jon Lin Subject: Re: [PATCH] spi: rockchip: Avoid redundant clock disable in pm operation To: Brian Norris Cc: broonie@kernel.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org, heiko@sntech.de, linux-arm-kernel@lists.infradead.org, linux-spi@vger.kernel.org References: <20240825035422.900370-1-jon.lin@rock-chips.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-HM-Spam-Status: e1kfGhgUHx5ZQUpXWQgPGg8OCBgUHx5ZQUlOS1dZFg8aDwILHllBWSg2Ly tZV1koWUFDSUNOT01LS0k3V1ktWUFJV1kPCRoVCBIfWUFZGUxMHlZITE5JHR5OGR1DTUtWFRQJFh oXVRMBExYaEhckFA4PWVdZGBILWUFZTkNVSUlVTFVKSk9ZV1kWGg8SFR0UWUFZT0tIVUpLSEpKQk xVSktLVUpCS0tZBg++ X-HM-Tid: 0a919176dba609d5kunm0c70c6e01b6 X-HM-MType: 1 X-HM-Sender-Digest: e1kMHhlZQR0aFwgeV1kSHx4VD1lBWUc6MDY6Cjo*CzIxKBwRPiINEDQR Dg8wCxFVSlVKTElPTElJSExJS0lJVTMWGhIXVREUFVUXEhU7CRQYEFYYExILCFUYFBZFWVdZEgtZ QVlOQ1VJSVVMVUpKT1lXWQgBWUFPT09DNwY+ X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240826_183319_559033_D1DE7EBF X-CRM114-Status: GOOD ( 25.83 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2024/8/27 6:27, Brian Norris wrote: > (NB: I have several nearly identical copies of this email. I'm replying > to the latest one I see.) > > Hi Jon, > > On Sun, Aug 25, 2024 at 11:54:22AM +0800, Jon Lin wrote: >> Fix WARN_ON: >> [ 22.869352][ T1885] clk_spi0 already unprepared >> [ 22.869379][ T1885] WARNING: CPU: 3 PID: 1885 at drivers/clk/clk.c:813 clk_core_unprepare+0xbc4 >> [ 22.869380][ T1885] Modules linked in: bcmdhd dhd_static_buf >> [ 22.869391][ T1885] CPU: 3 PID: 1885 Comm: Binder:355_2 Tainted: G W 5.10.66 #59 >> [ 22.869393][ T1885] Hardware name: Rockchip RK3588 EVB1 LP4 V10 Board (DT) >> [ 22.869397][ T1885] pstate: 60400009 (nZCv daif +PAN -UAO -TCO BTYPE=--) >> [ 22.869401][ T1885] pc : clk_core_unprepare+0xbc/0x214 >> [ 22.869404][ T1885] lr : clk_core_unprepare+0xbc/0x214 > > I appreciate the snippet of a WARNING trace, but I'd also appreciate > some actual explanation of what the problem is, and why you're solving > it this way. > Thank you for the reminder. >> Fixes: e882575efc77 ("spi: rockchip: Suspend and resume the bus during NOIRQ_SYSTEM_SLEEP_PM ops") >> Signed-off-by: Jon Lin >> --- >> >> drivers/spi/spi-rockchip.c | 57 +++++++++++++++++--------------------- >> 1 file changed, 26 insertions(+), 31 deletions(-) >> >> diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c >> index e1ecd96c7858..043a7739c330 100644 >> --- a/drivers/spi/spi-rockchip.c >> +++ b/drivers/spi/spi-rockchip.c > >> +#ifdef CONFIG_PM_SLEEP >> +static int rockchip_spi_suspend(struct device *dev) >> { >> + int ret; >> struct spi_controller *ctlr = dev_get_drvdata(dev); >> - struct rockchip_spi *rs = spi_controller_get_devdata(ctlr); >> >> - clk_disable_unprepare(rs->spiclk); >> - clk_disable_unprepare(rs->apb_pclk); >> + ret = spi_controller_suspend(ctlr); >> + if (ret < 0) >> + return ret; >> + >> + /* Avoid redundant clock disable */ >> + if (!pm_runtime_status_suspended(dev)) >> + rockchip_spi_runtime_suspend(dev); > > It seems like you'd really be served well by > pm_runtime_force_{suspend,resume}() here, and in fact, that's what this > driver used to use before the breaking change (commit > e882575efc77). Why aren't you just going back to using it? (This is the > kind of thing I might expect in your commit message -- reasoning as to > why you're doing what you're doing.) > > And in fact, I already submitted a patch that resolves the above problem > and does exactly that: > > https://lore.kernel.org/all/20240823214235.1718769-1-briannorris@chromium.org/ > [PATCH] spi: rockchip: Resolve unbalanced runtime PM / system PM handling > > Do you see any problem with it? > I have reviewed your submission and although the code has been simplified, the execution efficiency has decreased. So although it is a commonly used processing solution for SPI Upstream, I still hope to retain a more efficiency approach as I submitted. > Thanks, > Brian > >> + pinctrl_pm_select_sleep_state(dev); >> >> return 0; >> } >