On Tue, Nov 15, 2011 at 10:23:09AM +0100, Praveena NADAHALLY wrote: > Hello Felipe, > > Can you check and provide your comments for > the mail below? > > -----Original Message----- > From: Praveena NADAHALLY > Sent: Wednesday, October 26, 2011 7:03 PM > To: 'balbi@xxxxxx' > Cc: linux-usb@xxxxxxxxxxxxxxx; linus.walleij@xxxxxxxxxx; Sakethram > BOMMISETTI > Subject: RE: [PATCH] usb gadget: Endpoint configuration > > > What's the rationale for that ? > Already there are platform specific EP handling code for other > platforms in epautoconf.c file in usb_ep_autoconfig(). > Adding a new gadget_ops is based on a comment in > usb_ep_autoconfig(). Instead of changing the code in > epautoconf.c as done for few platforms, we thought it's a > good idea to add a gadget_ops so that each platform > can handle their EP configuration stuffs in their > platform files. > > > Why is ux500 so important that it needs > > to handle endpoint configuration by itself ? > > Why don't you just add a fifo_mode table for ux500 instead of adding > > this hack ? > > fifo_mode table is a onetime configuration during initialization. We > can't optimize this table for different USB configurations(like MSC, > serial, ECM as one config and ECM, serial as another config) > which user can change at run time by doing soft disconnect and > re-connect with a new configuration. > > In ux500, we would like handle EP configurations separately > for the following reasons: > * Allocate smaller than 512 bytes max packet EP to interrupt EP. > * Allocate a particular EP for a particular class. > This is mainly for allocating a double buffered and > DMA capable EP for a particular class like MSC... > * Any other platform specific checks... what we need with musb are patches which will benefit all users, not only ux500 or omap or any other. There are a bunch of registers on musb address space where you can ask the hardware how much FIFO space it has and how many endpoints it has, based on that, we need a way to better allocate FIFO space. Adding another function pointer which will only benefit ux500 is a no-no. All those fifo tables should go away and we should allocate fifo space dynamically, that's why we have dynamic fifo sizing on musb to start with. -- balbi
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