From: jy0922.shim@samsung.com (Joonyoung Shim) Date: Wed, 01 Aug 2012 12:02:41 +0900 Subject: [PATCH 2/8 v2] ARM: EXYNOS5: Add machine data for USB 2.0 In-Reply-To: <201207291311.08012.arnd@arndb.de> References: <1342866729-30460-1-git-send-email-gautam.vivek@samsung.com> <201207261124.50141.arnd@arndb.de> <201207291311.08012.arnd@arndb.de> Message-ID: <50189C51.8080409@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 07/29/2012 10:11 PM, Arnd Bergmann wrote: > On Saturday 28 July 2012, Vivek Gautam wrote: >>> Can you pleae explain why this is done in the changelog? >>> >>> We try hard to do such mappings from the device driver instead, >>> so I'm surprised that this is necessary fo rthe USB phy. >>> >> We are doing the mapping for device address in the driver, but this memory >> mapping for USB PHY registers that need to be programmed by the software >> is done here. This is similar to what we see for exynos4 also. Is it >> something >> that i can still change? Please suggest. > > Yes, I think the USB PHY handling for all exynos chips should be changed > from an ad-hoc method to a more formal device driver. As I commented > in another patch of this series, I think the main problem is that > treat the USB PHY as a property of the "platform", which it really isn't. > > We have a bunch of other USB PHY drivers for other platforms that are > inside of the drivers/usb hierarchy. For all I know, there is no formal > USB PHY driver API yet, and it seems that it would be a good idea to > introduce one now, but for now, just move the code to > drivers/usb/phy/ and make it one file per different kind of PHY. > Totally agree. I think that two PHY drivers need for usb2.0 PHY and usb3.0 PHY in drivers/usb/phy directory. First, let's make usb2.0 PHY driver for samsung SoCs from phy control codes of arch/arm, then add to support usb2.0 PHY for exynos5 and make usb3.0 PHY driver for exynos. Thanks.