[PATCH 04/11] ARM: OMAP2+: usb_host_fs: add custom reset for usb_host_fs (fsusb)

Felipe Balbi balbi at ti.com
Thu Jun 7 03:33:24 EDT 2012


Hi,

On Thu, Jun 07, 2012 at 12:31:13AM -0700, Tony Lindgren wrote:
> * Paul Walmsley <paul at pwsan.com> [120606 23:26]:
> > From: Tero Kristo <t-kristo at ti.com>
> > 
> > Add a custom reset function for the usb_host_fs/fsusb IP block, and
> > connect it to the OMAP4 FSUSB block.
> > 
> > This is the first of two fixes required to get rid of the boot
> > warning:
> > 
> > omap_hwmod: usb_host_fs: _wait_target_disable failed
> > 
> > and to allow the module to idle.
> > 
> > It may be necessary to use this reset method for OMAP2xxx SoCs as
> > well; this is left for a future patch.
> 
> Here too I think driver like features like this should live in the
> driver init for omap OHCI driver. In the likely case that FS OHCI is
> not in use on the board, the OHCI glue can just reset it.

this I don't agree. It means we will have to add some OHCI code even
when OHCI is disabled.

> > +/* HCCOMMANDSTATUS: the register offset of the HCCOMMANDSTATUS register */
> > +#define HCCOMMANDSTATUS			0x0008
> > +
> > +/* HCCOMMANDSTATUS_HCR: the bitmask of the host controller reset flag */
> > +#define HCCOMMANDSTATUS_HCR_MASK	(1 << 0)
> 
> I don't think the bus layer code should need to know anything about driver
> specific registers.
> 
> > +	omap_hwmod_write(HCCOMMANDSTATUS_HCR_MASK, oh, HCCOMMANDSTATUS);
> > +
> > +	omap_test_timeout(!(omap_hwmod_read(oh, HCCOMMANDSTATUS)
> > +			    & HCCOMMANDSTATUS_HCR_MASK),
> > +			  MAX_MODULE_SOFTRESET_WAIT, c);
> > +
> 
> These should be accessed by the driver in a standard way after ioremapping
> the device.

agree.

-- 
balbi
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