From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian Hunter Subject: Re: [PATCH] sdhci: expose the SDCLK frq in sys ios Date: Thu, 20 Oct 2011 09:22:04 +0300 Message-ID: <4E9FBE0C.7040002@intel.com> References: <1319031945-2630-1-git-send-email-peppe.cavallaro@st.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mga14.intel.com ([143.182.124.37]:2528 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932493Ab1JTGWH (ORCPT ); Thu, 20 Oct 2011 02:22:07 -0400 In-Reply-To: <1319031945-2630-1-git-send-email-peppe.cavallaro@st.com> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Giuseppe CAVALLARO Cc: linux-mmc@vger.kernel.org On 19/10/11 16:45, Giuseppe CAVALLARO wrote: > This patch is to expose the SDCLK frequency in the ios /sys entry. > > For example, if the max clk for a normal speed card is 20MHz > this will be reported in /sys/kernel/debug/mmc0/ios instead of > the real SDCLK frequency (calculated as Baseclock / divisor; > divisor used for programming the Clock Control Register). > > Signed-off-by: Giuseppe Cavallaro > --- > drivers/mmc/host/sdhci.c | 9 ++++++++- > 1 files changed, 8 insertions(+), 1 deletions(-) > > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c > index 0e02cc1..6bdf64f 100644 > --- a/drivers/mmc/host/sdhci.c > +++ b/drivers/mmc/host/sdhci.c > @@ -1045,6 +1045,7 @@ static void sdhci_set_clock(struct sdhci_host *host, unsigned int clock) > int div = 0; /* Initialized for compiler warning */ > u16 clk = 0; > unsigned long timeout; > + unsigned int new_hc_clock = host->max_clk; > > if (clock == host->clock) > return; > @@ -1134,7 +1135,10 @@ static void sdhci_set_clock(struct sdhci_host *host, unsigned int clock) > sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL); > > out: > - host->clock = clock; > + if (div) > + new_hc_clock = host->max_clk / div; At this point div is the value written to the register not the divisor > + > + host->clock = new_hc_clock; > } > > static void sdhci_set_power(struct sdhci_host *host, unsigned short power) > @@ -1293,6 +1297,9 @@ static void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) > > sdhci_set_clock(host, ios->clock); > > + /* Clock provided to the HC */ > + ios->clock = host->clock; It would be nicer to keep ios->clock as the target frequency and add a new member to struct mmc_host for the actual frequency. > + > if (ios->power_mode == MMC_POWER_OFF) > sdhci_set_power(host, -1); > else