From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AB8JxZpe9kSTVUMfUQiQ1kMa8YvHocJJO7k2g6/USYVO6Ik8bN7pLimw19pl6Y5V1CDcUzu9Aw+A ARC-Seal: i=1; a=rsa-sha256; t=1525100578; cv=none; d=google.com; s=arc-20160816; b=QNSOEne/p139QPtORxgmy5Iqx4gd3SkK4cNDwXkRfkQ9QrWQf6J6lOlv9/sIHoFMzj iN9elCck0HKvvTUBcDUtM2IxYhkulDDZX4Cf35IPd5uNLHNhCa57oWb8WbihDvcXpTk9 K9dtwW+hqQEsy1reYjNUS3Z/9X0md0KPCmckblNExHaaaNbM6MXhz47GgrIefxedY/AF mcFVjuV0vH8TiuKSn409JoJtDUmUElhYR2CwHCQvJMQtQeKwX8dNwAbOVR5nsrRjeyPa 39JkHGPq1vzYM3/wl4IVUA5zN6tGoWWW3mN1ukFihTqYrGiZ8VS2tDwzCrbGR6csLSsc 31KQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:date:message-id:mime-version:subject :references:in-reply-to:cc:to:envelope-from:from:dkim-signature :arc-authentication-results; bh=LwCXQ+BQma9Z/1SwUG8lHNGZjZADMXquWzgZ1L+BrSg=; b=PJTiTkd1RRqlLrDNHnFr46zQaY6LCFw8x12nyup44gvMp2/cmy0RY07MEVGYuTbROq vFlyeNNMgmyiJH40bEPDOE5eEXIep+6t3NPXLdlQFd99wGO+N9zoQfFeLvJbl6bGWgYR hNO//aO0WwCRDOnNgKJD1WpwOS8Wlkci9JrBgmFFOdDHZRehCrHicPF4lNG/4cgo2b3U au8hcfokhyCXosOuFnS2pfMooo2Kw4IKUgOtUgTE68ztW9mTqWlw9UvuSkcmsqYqURUu rzsK0k/hdaUwhvFBvstMp4/s4Pljb9bHOsuQ+L8AMz7jF4esDHrjObQKtlmHcpEKlR2G G+SA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@yandex.ru header.s=mail header.b=HYPY7PXH; spf=pass (google.com: domain of drustafa@yandex.ru designates 2a02:6b8:0:1630::17 as permitted sender) smtp.mailfrom=drustafa@yandex.ru Authentication-Results: mx.google.com; dkim=pass header.i=@yandex.ru header.s=mail header.b=HYPY7PXH; spf=pass (google.com: domain of drustafa@yandex.ru designates 2a02:6b8:0:1630::17 as permitted sender) smtp.mailfrom=drustafa@yandex.ru Authentication-Results: mxback1g.mail.yandex.net; dkim=pass header.i=@yandex.ru From: Evgeniy Polyakov Envelope-From: drustafa@yandex.ru To: Stefan Potyra , "linux-kernel@vger.kernel.org" , Greg Kroah-Hartman Cc: "ldv-project@linuxtesting.org" , "sil2review@lists.osadl.org" In-Reply-To: <20180419130254.7nriykiybpyi6j2g@agrajag.zerfleddert.de> References: <20180419130254.7nriykiybpyi6j2g@agrajag.zerfleddert.de> Subject: Re: [PATCH] Enable clock before calling clk_get_rate() on it. MIME-Version: 1.0 Message-Id: <4863111525100577@web2o.yandex.ru> X-Mailer: Yamail [ http://yandex.ru ] 5.0 Date: Mon, 30 Apr 2018 18:02:57 +0300 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=utf-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcSW1wb3J0YW50Ig==?= X-GMAIL-THRID: =?utf-8?q?1599183864651429148?= X-GMAIL-MSGID: =?utf-8?q?1599183864651429148?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Hi Stefan Nice catch, thank you! 19.04.2018, 16:02, "Stefan Potyra" : > According to the API, you may only call clk_get_rate() after actually > enabling it. > > Found by Linux Driver Verification project (linuxtesting.org). > > Fixes: a5fd9139f74c w1: add 1-wire master driver for i.MX27 / i.MX31 > Signed-off-by: Stefan Potyra Acked-by: Evgeniy Polyakov Greg, please pull it into your tree. Is this a stable material? > --- >  drivers/w1/masters/mxc_w1.c | 8 ++++---- >  1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/drivers/w1/masters/mxc_w1.c b/drivers/w1/masters/mxc_w1.c > index 74f2e6e6202a..a9599027d4ef 100644 > --- a/drivers/w1/masters/mxc_w1.c > +++ b/drivers/w1/masters/mxc_w1.c > @@ -112,6 +112,10 @@ static int mxc_w1_probe(struct platform_device *pdev) >          if (IS_ERR(mdev->clk)) >                  return PTR_ERR(mdev->clk); > > + err = clk_prepare_enable(mdev->clk); > + if (err) > + return err; > + >          clkrate = clk_get_rate(mdev->clk); >          if (clkrate < 10000000) >                  dev_warn(&pdev->dev, > @@ -128,10 +132,6 @@ static int mxc_w1_probe(struct platform_device *pdev) >          if (IS_ERR(mdev->regs)) >                  return PTR_ERR(mdev->regs); > > - err = clk_prepare_enable(mdev->clk); > - if (err) > - return err; > - >          /* Software reset 1-Wire module */ >          writeb(MXC_W1_RESET_RST, mdev->regs + MXC_W1_RESET); >          writeb(0, mdev->regs + MXC_W1_RESET); > -- > 2.17.0