[PATCH 3/3] USB: Add S5P OHCI diver

[jg1.han@samsung.com (Jingoo Han)]

Kukjin Kim wrote:
> Subject: RE: [PATCH 3/3] USB: Add S5P OHCI diver
> 
> Jingoo Han wrote:
> >
> > This patch adds USB OHCI driver for Samsung S5P SoCs.
> >
> > Signed-off-by: Jingoo Han <jg1.han@samsung.com>
> > ---
> >  drivers/usb/Kconfig         |    1 +
> >  drivers/usb/host/Kconfig    |    6 +
> >  drivers/usb/host/ohci-hcd.c |    5 +
> >  drivers/usb/host/ohci-s5p.c |  273
> > +++++++++++++++++++++++++++++++++++++++++++
> >  4 files changed, 285 insertions(+), 0 deletions(-)
> >  create mode 100644 drivers/usb/host/ohci-s5p.c
> >
> 
> (snip)
> 
> > +#ifdef CONFIG_PM
> > +static int s5p_ohci_suspend(struct device *dev)
> > +{
> > +	struct s5p_ohci_hcd *s5p_ohci = dev_get_drvdata(dev);
> > +	struct usb_hcd *hcd = s5p_ohci->hcd;
> > +	struct ohci_hcd *ohci = hcd_to_ohci(hcd);
> > +	struct platform_device *pdev = to_platform_device(dev);
> > +	struct s5p_ohci_platdata *pdata = pdev->dev.platform_data;
> > +	unsigned long flags;
> > +	int rc = 0;
> > +
> > +	/* Root hub was already suspended. Disable irq emission and
> > +	 * mark HW unaccessible, bail out if RH has been resumed. Use
> > +	 * the spinlock to properly synchronize with possible pending
> > +	 * RH suspend or resume activity.
> > +	 *
> > +	 * This is still racy as hcd->state is manipulated outside of
> > +	 * any locks =P But that will be a different fix.
> > +	 */
> > +	spin_lock_irqsave(&ohci->lock, flags);
> > +	if (hcd->state != HC_STATE_SUSPENDED && hcd->state != HC_STATE_HALT)
> > {
> > +		rc = -EINVAL;
> > +		goto fail;
> > +	}
> > +
> > +	clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
> > +
> > +	if (pdata && pdata->phy_exit)
> > +		pdata->phy_exit(pdev, S5P_USB_PHY_HOST);
> 
> Since ohci and echi share the code for control of phy, this can make a
> problem when this is used by module or doing suspend-to-resume. So need to
> sort it out.
OK, I will fix phy control function.
> 
> And how about to use ohci-exynos instead of ohci-s5p? As you know, this
> can/will be used on EXYNOS SoCs.
OK, I will use ohci-exynos.
Thanks.
> 
> Others, ok to me. If you address comments from me, you can add my ack.
> 
> Thanks.
> 
> Best regards,
> Kgene.
> --
> Kukjin Kim <kgene.kim@samsung.com>, Senior Engineer,
> SW Solution Development Team, Samsung Electronics Co., Ltd.