[U-Boot] [PATCH v4 2/3] mmc: dw_mmc: Support bypass mode with the get_mmc_clk() method

Marek Vasut marex at denx.de
Fri Aug 7 04:58:02 CEST 2015


On Friday, August 07, 2015 at 04:54:42 AM, Simon Glass wrote:
> Hi Marek,

Hi Simon,

> On 6 August 2015 at 20:51, Marek Vasut <marex at denx.de> wrote:
> > On Friday, August 07, 2015 at 04:16:28 AM, Simon Glass wrote:
> >> Some SoCs want to adjust the input clock to the DWMMC block as a way of
> >> controlling the MMC bus clock. Update the get_mmc_clk() method to
> >> support this.
> >> 
> >> Signed-off-by: Simon Glass <sjg at chromium.org>
> > 
> > Hi Simon,
> > 
> >> ---
> >> 
> >> Changes in v4:
> >> - Update commit message to indicate this patch is for the dw_mmc driver
> >> 
> >>  drivers/mmc/dw_mmc.c        |  2 +-
> >>  drivers/mmc/exynos_dw_mmc.c |  2 +-
> >>  include/dwmmc.h             | 16 +++++++++++++++-
> >>  3 files changed, 17 insertions(+), 3 deletions(-)
> >> 
> >> diff --git a/drivers/mmc/dw_mmc.c b/drivers/mmc/dw_mmc.c
> >> index 8f28d7e..a034c3f 100644
> >> --- a/drivers/mmc/dw_mmc.c
> >> +++ b/drivers/mmc/dw_mmc.c
> >> @@ -248,7 +248,7 @@ static int dwmci_setup_bus(struct dwmci_host *host,
> >> u32 freq) * host->bus_hz should be set by user.
> >> 
> >>        */
> >>       
> >>       if (host->get_mmc_clk)
> >> 
> >> -             sclk = host->get_mmc_clk(host);
> >> +             sclk = host->get_mmc_clk(host, freq);
> > 
> > Why are you passing the @freq into get_mmc_clk() ? Shouldn't you call
> > some clock framework function to determine the input frequency of the
> > DWMMC block from within the get_mmc_clk() implementation instead ? What
> > do you think please ?
> 
> Well, yes. If such a clock frame work existed I would call it :-) We
> do have a uclass now so we are getting there.

Excellent, so do you really need this kind of patch ? :) Why don't you make
just some kind of function -- get_dwmmc_clock() -- and call it instead ?

Best regards,
Marek Vasut


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