From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nicolas Ferre Subject: Re: [PATCH 1/5] USB: ehci-atmel: rework clk handling Date: Wed, 18 Mar 2015 12:16:22 +0100 Message-ID: <55095E86.1060201@atmel.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Alan Stern , Greg Kroah-Hartman Cc: Boris Brezillon , Jean-Christophe Plagniol-Villard , Alexandre Belloni , Felipe Balbi , linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Douglas Gilbert , Robert Nelson List-Id: devicetree@vger.kernel.org Le 17/03/2015 20:01, Alan Stern a =E9crit : > On Tue, 17 Mar 2015, Boris Brezillon wrote: >=20 >> The EHCI IP only needs the UTMI/UPLL (uclk) and the peripheral (iclk= ) >> clocks to work properly. Remove the useless system clock (fclk). >> >> Avoid calling set_rate on the fixed rate UTMI/IPLL clock and remove >> useless IS_ENABLED(CONFIG_COMMON_CLK) tests (all at91 platforms have= been >> moved to the CCF). >> >> This patch also fixes a bug introduced by 3440ef1 (ARM: at91/dt: fix= USB >> high-speed clock to select UTMI), which was leaving the usb clock >> uninitialized and preventing the OHCI driver from setting the usb cl= ock >> rate to 48MHz. >> This bug was caused by several things: >> 1/ usb clock drivers set the CLK_SET_RATE_GATE flag, which means the= rate >> cannot be changed once the clock is prepared >> 2/ The EHCI driver was retrieving and preparing/enabling the uhpck >> clock which was in turn preparing its parent clock (the usb clock= ), >> thus preventing any rate change because of 1/ >> >> Signed-off-by: Boris Brezillon >=20 > Acked-by: Alan Stern Acked-by: Nicolas Ferre and: =46ixes: 3440ef169100 ("ARM: at91/dt: fix USB high-speed clock to selec= t UTMI") Alan, Greg, Can you please take this patch (only this patch 1/5 of the series) as a= fix=20 for the 4.0-rc? It would solve the issue that we see on at91sam9x5/at91= sam9n12. I'll take care of the rest of the series for 4.1. If you want me to take it of to re-send the patch, tell me. Thanks, bye, --=20 Nicolas Ferre -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html