Hi Ravi, On 08.04.2013 12:42, B, Ravi wrote: >> Subject: [PATCH v2 07/11] usb: musb: add Kconfig options for HOST, GAGDET >> or DUAL_ROLE modes >> >> This makes building the actual object files optional to the selected >> mode, which saves users who know which kind of USB mode support they >> need some binary size. >> >> Unimplemented functions are stubbed out with static inline functions. >> >> Signed-off-by: Daniel Mack <zonque@xxxxxxxxx> >> --- >> drivers/usb/musb/Kconfig | 29 +++++++++++++++++++++++++++++ >> drivers/usb/musb/Makefile | 10 ++++++++-- >> drivers/usb/musb/musb_gadget.h | 21 +++++++++++++++++++++ >> drivers/usb/musb/musb_host.h | 29 +++++++++++++++++++++++++++-- >> 4 files changed, 85 insertions(+), 4 deletions(-) >> >> diff --git a/drivers/usb/musb/Kconfig b/drivers/usb/musb/Kconfig >> index 47442d3..aab1568 100644 >> --- a/drivers/usb/musb/Kconfig >> +++ b/drivers/usb/musb/Kconfig >> @@ -28,6 +28,35 @@ config USB_MUSB_HDRC >> if USB_MUSB_HDRC >> >> choice >> + bool "MUSB Mode Selection" >> + default USB_MUSB_DUAL_ROLE if (USB && USB_GADGET) >> + default USB_MUSB_HOST if (USB && !USB_GADGET) >> + default USB_MUSB_GADGET if (!USB && USB_GADGET) >> + >> +config USB_MUSB_HOST >> + bool "Host only mode" >> + depends on USB >> + help >> + Select this when you want to use MUSB in host mode only, >> + thereby the gadget feature will be regressed. >> + >> +config USB_MUSB_GADGET >> + bool "Gadget only mode" >> + depends on USB_GADGET >> + help >> + Select this when you want to use MUSB in gadget mode only, >> + thereby the host feature will be regressed. >> + >> +config USB_MUSB_DUAL_ROLE >> + bool "Dual Role mode" >> + depends on (USB && USB_GADGET) >> + help >> + This is the default mode of working of MUSB controller where >> + both host and gadget features are enabled. >> + >> +endchoice > > How do you cater for multi-instance support? Where one controller to force as host and other as device (similar to am33x beagle configuration). > In general for all combination possible like <host, host> <host, device> <device, host> <dual, dual> etc. The actual mode chosen for an instance is passed in via pdata/DT. The Kconfig options only exist in order to stub out code that certainly isn't needed for a particular platform. IOW, to reduce the binary size. So the beagleboard will have to select the DUAL_ROLE config parameters, where other board (like mine) can go for the HOST only option. If a user selects a mode as runtime parameter that is stubbed out by the chosen config, it will simply don't do anything. Just as with a driver that is referenced from DT but not compiled in. I don't think we should be over-smart here and mess with the configured platform data. If the platform data is wrong, it has to be fixed anyway. Felipe, do you agree? Thanks, Daniel -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
