> -----Original Message----- > From: Alan Stern [mailto:stern@xxxxxxxxxxxxxxxxxxx] > Sent: Saturday, August 08, 2015 2:04 AM > To: Mehresh Ramneek-B31383 > Cc: linux-kernel@xxxxxxxxxxxxxxx; balbi@xxxxxx; > gregkh@xxxxxxxxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx; Li Yang-Leo-R58472 > Subject: Re: [PATCH 3/8][v2]usb:fsl:otg: Add support to add/remove usb > host driver > > On Wed, 15 Jul 2015, Ramneek Mehresh wrote: > > > Add workqueue to add/remove host driver (outside interrupt context) > > upon each id change. > > > > Signed-off-by: Li Yang <leoli@xxxxxxxxxxxxx> > > Signed-off-by: Ramneek Mehresh <ramneek.mehresh@xxxxxxxxxxxxx> > > --- > > drivers/usb/host/ehci-fsl.c | 83 > > ++++++++++++++++++++++++++++++++++----------- > > drivers/usb/host/ehci-fsl.h | 20 +++++++++++ > > 2 files changed, 84 insertions(+), 19 deletions(-) > > > > diff --git a/drivers/usb/host/ehci-fsl.c b/drivers/usb/host/ehci-fsl.c > > index 5352e74..81e4bf5 100644 > > --- a/drivers/usb/host/ehci-fsl.c > > +++ b/drivers/usb/host/ehci-fsl.c > > @@ -44,6 +44,34 @@ > > > > static struct hc_driver __read_mostly fsl_ehci_hc_driver; > > > > +#if defined(CONFIG_FSL_USB2_OTG) || > > +defined(CONFIG_FSL_USB2_OTG_MODULE) > > You've got these #if lines all over the place. They look ugly and make the > code hard to read. Consider removing them. Or even if you can't remove > them entirely, removing most of them would help. > > Also, instead of testing both CONFIG_FSL_USB2_OTG and > CONFIG_FSL_USB2_OTG_MODULE, how about testing a single symbol? For > example: > > #if defined(CONFIG_FSL_USB2_OTG) || > defined(CONFIG_FSL_USB2_OTG_MODULE) > #define CHANGE_HCD 1 > #else > #define CHANGE_HCD 0 > #endif > > Then all you need later on is "#if CHANGE_HCD". Or if it's inside a code block, > just "if (CHANGE_HCD)". > Ok, let me see what can be done to minimize these macros. Thanks > > +static struct ehci_fsl *hcd_to_ehci_fsl(struct usb_hcd *hcd) { > > + return (struct ehci_fsl *)hcd_to_ehci(hcd)->priv; } > > + > > +static void do_change_hcd(struct work_struct *work) { > > + struct ehci_fsl *ehci_fsl = container_of(work, struct ehci_fsl, > > + change_hcd_work); > > + struct usb_hcd *hcd = ehci_fsl->hcd; > > + void __iomem *non_ehci = hcd->regs; > > + int retval; > > + > > + if (ehci_fsl->hcd_add && !ehci_fsl->have_hcd) { > > + writel(USBMODE_CM_HOST, non_ehci + > FSL_SOC_USB_USBMODE); > > + /* host, gadget and otg share same int line */ > > + retval = usb_add_hcd(hcd, hcd->irq, IRQF_SHARED); > > + if (retval == 0) > > + ehci_fsl->have_hcd = 1; > > + } else if (!ehci_fsl->hcd_add && ehci_fsl->have_hcd) { > > + usb_remove_hcd(hcd); > > + ehci_fsl->have_hcd = 0; > > Don't you have to turn off the USBMODE_CM_HOST bit here? It looks > strange to turn it on above but not turn it off again. > USBMODE bit defines mode for the controller. It gets auto cleared when controller is reset in host/gadget driver. After resetting, it's mandatory to write this bit once to define controller's mode. > > + } > > +} > > +#endif > > > > static int ehci_fsl_drv_suspend(struct device *dev) { > > struct usb_hcd *hcd = dev_get_drvdata(dev); > > - struct ehci_fsl *ehci_fsl = hcd_to_ehci_fsl(hcd); > > void __iomem *non_ehci = hcd->regs; > > +#if defined(CONFIG_FSL_USB2_OTG) || > defined(CONFIG_FSL_USB2_OTG_MODULE) > > + struct ehci_fsl *ehci_fsl = hcd_to_ehci_fsl(hcd); > > + struct usb_bus host = hcd->self; > > +#endif > > + > > > > if (of_device_is_compatible(dev->parent->of_node, > > "fsl,mpc5121-usb2-dr")) { > > return ehci_fsl_mpc512x_drv_suspend(dev); > > } > > > > +#if defined(CONFIG_FSL_USB2_OTG) || > defined(CONFIG_FSL_USB2_OTG_MODULE) > > + if (host.is_otg) { > > + /* remove hcd */ > > + ehci_fsl->hcd_add = 0; > > + schedule_work(&ehci_fsl->change_hcd_work); > > + host.is_otg = 0; > > Why do you set host.is_otg to 0 here? Why not do it in the work routine? Well, it can be done there also. I just wanted to keep host-bus house-keeping out of otg role-changing specific workqueue (where host driver is brought-up/shut-down). > > > + return 0; > > + } > > +#endif > > + > > ehci_prepare_ports_for_controller_suspend(hcd_to_ehci(hcd), > > device_may_wakeup(dev)); > > if (!fsl_deep_sleep()) > > @@ -540,15 +571,29 @@ static int ehci_fsl_drv_suspend(struct device > > *dev) static int ehci_fsl_drv_resume(struct device *dev) { > > struct usb_hcd *hcd = dev_get_drvdata(dev); > > - struct ehci_fsl *ehci_fsl = hcd_to_ehci_fsl(hcd); > > struct ehci_hcd *ehci = hcd_to_ehci(hcd); > > void __iomem *non_ehci = hcd->regs; > > +#if defined(CONFIG_FSL_USB2_OTG) || > defined(CONFIG_FSL_USB2_OTG_MODULE) > > + struct ehci_fsl *ehci_fsl = hcd_to_ehci_fsl(hcd); > > + struct usb_bus host = hcd->self; > > +#endif > > > > if (of_device_is_compatible(dev->parent->of_node, > > "fsl,mpc5121-usb2-dr")) { > > return ehci_fsl_mpc512x_drv_resume(dev); > > } > > > > +#if defined(CONFIG_FSL_USB2_OTG) || > defined(CONFIG_FSL_USB2_OTG_MODULE) > > + if (host.is_otg) { > > + /* add hcd */ > > + ehci_fsl->hcd_add = 1; > > + schedule_work(&ehci_fsl->change_hcd_work); > > + usb_hcd_resume_root_hub(hcd); > > + host.is_otg = 0; > > Again, why change host.is_otg here? And for that matter, where does > host.is_otg ever get set to 1? host.is_otg sets to 1 in phy driver before calling ehci drv suspend/resume. This is donr to make it clear in host drv suspend/resume that these functions Are called in context of otg drv > > Also, what is the reason for calling usb_hcd_resume_root_hub()? It won't > do anything, because it will run before the scheduled work, so there won't > be a root hub for it to resume. > Well, you're right...it's not a surety that usb_hcd_resume_root_hub() will run after scheduled work...i'll move it inside do_change_hcd() after usb_add_hcd(). Thanks. > > + return 0; > > + } > > +#endif > > + > > ehci_prepare_ports_for_controller_resume(ehci); > > if (!fsl_deep_sleep()) > > return 0; > > diff --git a/drivers/usb/host/ehci-fsl.h b/drivers/usb/host/ehci-fsl.h > > index dbd292e..3fd1fd0 100644 > > --- a/drivers/usb/host/ehci-fsl.h > > +++ b/drivers/usb/host/ehci-fsl.h > > @@ -62,4 +62,24 @@ > > #define UTMI_PHY_EN (1<<9) > > #define ULPI_PHY_CLK_SEL (1<<10) > > #define PHY_CLK_VALID (1<<17) > > + > > +struct ehci_fsl { > > +#ifdef CONFIG_PM > > + /* Saved USB PHY settings, need to restore after deep sleep. */ > > + u32 usb_ctrl; > > +#endif > > + struct usb_hcd *hcd; > > +#if defined(CONFIG_FSL_USB2_OTG) || > defined(CONFIG_FSL_USB2_OTG_MODULE) > > + struct work_struct change_hcd_work; > > +#endif > > Again, try to eliminate these #if's. There really isn't anything wrong with > allocating the space for these things even in a non-OTG build. > > > + /* > > + * store current hcd state for otg; > > + * have_hcd is true when host drv al already part of otg framework, > > + * otherwise false; > > + * hcd_add is true when otg framework wants to add host > > + * drv as part of otg;flase when it wants to remove it > > + */ > > + unsigned have_hcd:1; > > + unsigned hcd_add:1; > > +}; > > #endif /* _EHCI_FSL_H */ > > Alan Stern -- 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
