From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shawn Lin Subject: Re: [PATCH] mmc: Add a restriction to mmc debugfs clock setting. Date: Tue, 19 Jan 2016 14:35:29 +0800 Message-ID: <569DD931.6050001@rock-chips.com> References: <1453183995-46099-1-git-send-email-pawelx.wodkowski@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=gbk; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from lucky1.263xmail.com ([211.157.147.131]:45716 "EHLO lucky1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751409AbcASGf4 (ORCPT ); Tue, 19 Jan 2016 01:35:56 -0500 In-Reply-To: <1453183995-46099-1-git-send-email-pawelx.wodkowski@intel.com> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Pawel Wodkowski , linux-mmc@vger.kernel.org Cc: shawn.lin@rock-chips.com, Chuanxiao Dong , Yuan Juntao On 2016/1/19 14:13, Pawel Wodkowski wrote: > From: Chuanxiao Dong > > Clock frequency values written to an mmc host should not be less than > the minimum clock frequency which the mmc host supports. > > Signed-off-by: Yuan Juntao > Signed-off-by: Pawel Wodkowski > --- > drivers/mmc/core/debugfs.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/mmc/core/debugfs.c b/drivers/mmc/core/debugfs.c > index 154aced0b91b..bdfce774d848 100644 > --- a/drivers/mmc/core/debugfs.c > +++ b/drivers/mmc/core/debugfs.c > @@ -220,7 +220,7 @@ static int mmc_clock_opt_set(void *data, u64 val) > struct mmc_host *host = data; > > /* We need this check due to input value is u64 */ > - if (val > host->f_max) > + if (val > host->f_max || val < host->f_min) Hmm... how about if I want to disable clk from sysfs and pass ZERO to mmc_clock_opt_set, doesn't that case make sense? :) > return -EINVAL; > > mmc_claim_host(host); > -- Best Regards Shawn Lin