From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexandru Stan Subject: Re: [PATCH v2 1/2] clk: rockchip: add bindings for the mmc clock phases Date: Mon, 17 Nov 2014 11:50:51 -0800 Message-ID: References: <1416009604-31545-1-git-send-email-amstan@chromium.org> <1416009604-31545-2-git-send-email-amstan@chromium.org> <20141117193902.25314.97687@quantum> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: <20141117193902.25314.97687@quantum> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Mike Turquette Cc: Heiko Stuebner , Doug Anderson , addy ke , Sonny Rao , Kever Yang , linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, pawel.moll-5wv7dgnIgG8@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org, ijc+devicetree-KcIKpvwj1kUDXYZnReoRVg@public.gmane.org, galak-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, mark.yao-TNX95d0MmH7DzftRWevZcw@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org Sorry for my previous mail, I sent it as HTML and also top posted. Here it goes again: On Mon, Nov 17, 2014 at 11:39 AM, Mike Turquette wrote: > It looks like you are adding new clocks to handle the phase requirement. > Is that the right thing to do? Don't these clks already exist (e.g. > SCLK_SDMMC)? I actually need to control 2 phases, one of them is used when outputting data, the other when sampling. Sunxi does something similar: http://lists.infradead.org/pipermail/linux-arm-kernel/2014-July/273273.html Another reason it wouldn't work is because the upstream clock(eg SCLK_SDMMC) is twice as fast as the real clock(see RK3288_CLKGEN_DIV in drivers/mmc/host/dw_mmc-rockchip.c), since that clock goes to a /2 divider to be able to do the 90 degree clock phases. Alexandru Stan -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html