From dd40438fc6be7454c906093fe2a1b69ca98946fb Mon Sep 17 00:00:00 2001 From: Martin Blumenstingl Date: Wed, 18 Apr 2018 21:39:46 +0200 Subject: usb: core: phy: fix return value of usb_phy_roothub_exit() usb_phy_roothub_exit() should return the error code from the phy_exit() call if exiting the PHY failed. However, since a wrong variable is used usb_phy_roothub_exit() currently always returns 0, even if one of the phy_exit calls returned an error. Clang also reports this bug: kernel/drivers/usb/core/phy.c:114:8: warning: explicitly assigning value of variable of type 'int' to itself [-Wself-assign] error, forbidden warning: phy.c:114 Fix this by assigning the error code from phy_exit() to the "ret" variable to propagate the error correctly. Fixes: 07dbff0ddbd86c ("usb: core: add a wrapper for the USB PHYs on the HCD") Signed-off-by: Martin Blumenstingl Signed-off-by: Rishabh Bhatnagar Tested-by: Keerthy Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/phy.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/usb/core/phy.c') diff --git a/drivers/usb/core/phy.c b/drivers/usb/core/phy.c index 09b7c43c0ea4..f19aaa3c899c 100644 --- a/drivers/usb/core/phy.c +++ b/drivers/usb/core/phy.c @@ -111,7 +111,7 @@ int usb_phy_roothub_exit(struct usb_phy_roothub *phy_roothub) list_for_each_entry(roothub_entry, head, list) { err = phy_exit(roothub_entry->phy); if (err) - ret = ret; + ret = err; } return ret; -- cgit v1.2.3 From 63cb03f5c11eef2c08b5812f4533ba87cf778fa8 Mon Sep 17 00:00:00 2001 From: Martin Blumenstingl Date: Wed, 18 Apr 2018 21:39:47 +0200 Subject: usb: core: split usb_phy_roothub_{init,alloc} Before this patch usb_phy_roothub_init served two purposes (from a caller's point of view - like hcd.c): - parsing the PHYs and allocating the list entries - calling phy_init on each list entry While this worked so far it has one disadvantage: if we need to call phy_init for each PHY instance then the existing code cannot be re-used. Solve this by splitting off usb_phy_roothub_alloc which only parses the PHYs and allocates the list entries. usb_phy_roothub_init then gets a struct usb_phy_roothub and only calls phy_init on each PHY instance (along with the corresponding cleanup if that failed somewhere). This is a preparation step for adding proper suspend support for some hardware that requires phy_exit to be called during suspend and phy_init to be called during resume. Signed-off-by: Martin Blumenstingl Tested-by: Chunfeng Yun Reviewed-by: Roger Quadros Tested-by: Keerthy Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hcd.c | 10 +++++++--- drivers/usb/core/phy.c | 53 +++++++++++++++++++++++++------------------------- drivers/usb/core/phy.h | 4 +++- 3 files changed, 37 insertions(+), 30 deletions(-) (limited to 'drivers/usb/core/phy.c') diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index 00bb8417050f..f0e5f4d875d8 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -2759,12 +2759,16 @@ int usb_add_hcd(struct usb_hcd *hcd, } if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) { - hcd->phy_roothub = usb_phy_roothub_init(hcd->self.sysdev); + hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev); if (IS_ERR(hcd->phy_roothub)) { retval = PTR_ERR(hcd->phy_roothub); - goto err_phy_roothub_init; + goto err_phy_roothub_alloc; } + retval = usb_phy_roothub_init(hcd->phy_roothub); + if (retval) + goto err_phy_roothub_alloc; + retval = usb_phy_roothub_power_on(hcd->phy_roothub); if (retval) goto err_usb_phy_roothub_power_on; @@ -2937,7 +2941,7 @@ err_create_buf: usb_phy_roothub_power_off(hcd->phy_roothub); err_usb_phy_roothub_power_on: usb_phy_roothub_exit(hcd->phy_roothub); -err_phy_roothub_init: +err_phy_roothub_alloc: if (hcd->remove_phy && hcd->usb_phy) { usb_phy_shutdown(hcd->usb_phy); usb_put_phy(hcd->usb_phy); diff --git a/drivers/usb/core/phy.c b/drivers/usb/core/phy.c index f19aaa3c899c..44f008cda7a8 100644 --- a/drivers/usb/core/phy.c +++ b/drivers/usb/core/phy.c @@ -19,19 +19,6 @@ struct usb_phy_roothub { struct list_head list; }; -static struct usb_phy_roothub *usb_phy_roothub_alloc(struct device *dev) -{ - struct usb_phy_roothub *roothub_entry; - - roothub_entry = devm_kzalloc(dev, sizeof(*roothub_entry), GFP_KERNEL); - if (!roothub_entry) - return ERR_PTR(-ENOMEM); - - INIT_LIST_HEAD(&roothub_entry->list); - - return roothub_entry; -} - static int usb_phy_roothub_add_phy(struct device *dev, int index, struct list_head *list) { @@ -45,9 +32,11 @@ static int usb_phy_roothub_add_phy(struct device *dev, int index, return PTR_ERR(phy); } - roothub_entry = usb_phy_roothub_alloc(dev); - if (IS_ERR(roothub_entry)) - return PTR_ERR(roothub_entry); + roothub_entry = devm_kzalloc(dev, sizeof(*roothub_entry), GFP_KERNEL); + if (!roothub_entry) + return -ENOMEM; + + INIT_LIST_HEAD(&roothub_entry->list); roothub_entry->phy = phy; @@ -56,11 +45,9 @@ static int usb_phy_roothub_add_phy(struct device *dev, int index, return 0; } -struct usb_phy_roothub *usb_phy_roothub_init(struct device *dev) +struct usb_phy_roothub *usb_phy_roothub_alloc(struct device *dev) { struct usb_phy_roothub *phy_roothub; - struct usb_phy_roothub *roothub_entry; - struct list_head *head; int i, num_phys, err; num_phys = of_count_phandle_with_args(dev->of_node, "phys", @@ -68,16 +55,31 @@ struct usb_phy_roothub *usb_phy_roothub_init(struct device *dev) if (num_phys <= 0) return NULL; - phy_roothub = usb_phy_roothub_alloc(dev); - if (IS_ERR(phy_roothub)) - return phy_roothub; + phy_roothub = devm_kzalloc(dev, sizeof(*phy_roothub), GFP_KERNEL); + if (!phy_roothub) + return ERR_PTR(-ENOMEM); + + INIT_LIST_HEAD(&phy_roothub->list); for (i = 0; i < num_phys; i++) { err = usb_phy_roothub_add_phy(dev, i, &phy_roothub->list); if (err) - goto err_out; + return ERR_PTR(err); } + return phy_roothub; +} +EXPORT_SYMBOL_GPL(usb_phy_roothub_alloc); + +int usb_phy_roothub_init(struct usb_phy_roothub *phy_roothub) +{ + struct usb_phy_roothub *roothub_entry; + struct list_head *head; + int err; + + if (!phy_roothub) + return 0; + head = &phy_roothub->list; list_for_each_entry(roothub_entry, head, list) { @@ -86,14 +88,13 @@ struct usb_phy_roothub *usb_phy_roothub_init(struct device *dev) goto err_exit_phys; } - return phy_roothub; + return 0; err_exit_phys: list_for_each_entry_continue_reverse(roothub_entry, head, list) phy_exit(roothub_entry->phy); -err_out: - return ERR_PTR(err); + return err; } EXPORT_SYMBOL_GPL(usb_phy_roothub_init); diff --git a/drivers/usb/core/phy.h b/drivers/usb/core/phy.h index 6fde59bfbff8..eb31253201ad 100644 --- a/drivers/usb/core/phy.h +++ b/drivers/usb/core/phy.h @@ -1,6 +1,8 @@ struct usb_phy_roothub; -struct usb_phy_roothub *usb_phy_roothub_init(struct device *dev); +struct usb_phy_roothub *usb_phy_roothub_alloc(struct device *dev); + +int usb_phy_roothub_init(struct usb_phy_roothub *phy_roothub); int usb_phy_roothub_exit(struct usb_phy_roothub *phy_roothub); int usb_phy_roothub_power_on(struct usb_phy_roothub *phy_roothub); -- cgit v1.2.3 From f0e36d478faf37fb26413b2530d04e6b30af3834 Mon Sep 17 00:00:00 2001 From: Martin Blumenstingl Date: Wed, 18 Apr 2018 21:39:48 +0200 Subject: usb: core: use phy_exit during suspend if wake up is not supported If the USB controller can wake up the system (which is the case for example with the Mediatek USB3 IP) then we must not call phy_exit during suspend to ensure that the USB controller doesn't have to re-enumerate the devices during resume. However, if the USB controller cannot wake up the system (which is the case for example on various TI platforms using a dwc3 controller) then we must call phy_exit during suspend. Otherwise the PHY driver keeps the clocks enabled, which prevents the system from reaching the lowest power levels in the suspend state. Solve this by introducing two new functions in the PHY wrapper which are dedicated to the suspend and resume handling. If the controller can wake up the system the new usb_phy_roothub_suspend function will simply call usb_phy_roothub_power_off. However, if wake up is not supported by the controller it will also call usb_phy_roothub_exit. The also new usb_phy_roothub_resume function takes care of calling usb_phy_roothub_init (if the controller can't wake up the system) in addition to usb_phy_roothub_power_on. Fixes: 07dbff0ddbd86c ("usb: core: add a wrapper for the USB PHYs on the HCD") Fixes: 178a0bce05cbc1 ("usb: core: hcd: integrate the PHY wrapper into the HCD core") Reported-by: Roger Quadros Suggested-by: Roger Quadros Suggested-by: Chunfeng Yun Signed-off-by: Martin Blumenstingl Tested-by: Chunfeng Yun Reviewed-by: Roger Quadros Tested-by: Keerthy Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hcd.c | 8 +++++--- drivers/usb/core/phy.c | 35 +++++++++++++++++++++++++++++++++++ drivers/usb/core/phy.h | 5 +++++ 3 files changed, 45 insertions(+), 3 deletions(-) (limited to 'drivers/usb/core/phy.c') diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index f0e5f4d875d8..0a42c5df3c0f 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -2262,7 +2262,8 @@ int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg) hcd->state = HC_STATE_SUSPENDED; if (!PMSG_IS_AUTO(msg)) - usb_phy_roothub_power_off(hcd->phy_roothub); + usb_phy_roothub_suspend(hcd->self.sysdev, + hcd->phy_roothub); /* Did we race with a root-hub wakeup event? */ if (rhdev->do_remote_wakeup) { @@ -2302,7 +2303,8 @@ int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) } if (!PMSG_IS_AUTO(msg)) { - status = usb_phy_roothub_power_on(hcd->phy_roothub); + status = usb_phy_roothub_resume(hcd->self.sysdev, + hcd->phy_roothub); if (status) return status; } @@ -2344,7 +2346,7 @@ int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) } } else { hcd->state = old_state; - usb_phy_roothub_power_off(hcd->phy_roothub); + usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub); dev_dbg(&rhdev->dev, "bus %s fail, err %d\n", "resume", status); if (status != -ESHUTDOWN) diff --git a/drivers/usb/core/phy.c b/drivers/usb/core/phy.c index 44f008cda7a8..a39d9bb26a4f 100644 --- a/drivers/usb/core/phy.c +++ b/drivers/usb/core/phy.c @@ -157,3 +157,38 @@ void usb_phy_roothub_power_off(struct usb_phy_roothub *phy_roothub) phy_power_off(roothub_entry->phy); } EXPORT_SYMBOL_GPL(usb_phy_roothub_power_off); + +int usb_phy_roothub_suspend(struct device *controller_dev, + struct usb_phy_roothub *phy_roothub) +{ + usb_phy_roothub_power_off(phy_roothub); + + /* keep the PHYs initialized so the device can wake up the system */ + if (device_may_wakeup(controller_dev)) + return 0; + + return usb_phy_roothub_exit(phy_roothub); +} +EXPORT_SYMBOL_GPL(usb_phy_roothub_suspend); + +int usb_phy_roothub_resume(struct device *controller_dev, + struct usb_phy_roothub *phy_roothub) +{ + int err; + + /* if the device can't wake up the system _exit was called */ + if (!device_may_wakeup(controller_dev)) { + err = usb_phy_roothub_init(phy_roothub); + if (err) + return err; + } + + err = usb_phy_roothub_power_on(phy_roothub); + + /* undo _init if _power_on failed */ + if (err && !device_may_wakeup(controller_dev)) + usb_phy_roothub_exit(phy_roothub); + + return err; +} +EXPORT_SYMBOL_GPL(usb_phy_roothub_resume); diff --git a/drivers/usb/core/phy.h b/drivers/usb/core/phy.h index eb31253201ad..605555901d44 100644 --- a/drivers/usb/core/phy.h +++ b/drivers/usb/core/phy.h @@ -7,3 +7,8 @@ int usb_phy_roothub_exit(struct usb_phy_roothub *phy_roothub); int usb_phy_roothub_power_on(struct usb_phy_roothub *phy_roothub); void usb_phy_roothub_power_off(struct usb_phy_roothub *phy_roothub); + +int usb_phy_roothub_suspend(struct device *controller_dev, + struct usb_phy_roothub *phy_roothub); +int usb_phy_roothub_resume(struct device *controller_dev, + struct usb_phy_roothub *phy_roothub); -- cgit v1.2.3 From fec94445db7777c65b0a681b8dc0ed2532304d2a Mon Sep 17 00:00:00 2001 From: Martin Blumenstingl Date: Wed, 18 Apr 2018 21:39:49 +0200 Subject: usb: core: phy: make it a no-op if CONFIG_GENERIC_PHY is disabled If the generic PHY support is disabled the stub of devm_of_phy_get_by_index returns ENOSYS. This corner case isn't handled properly by usb_phy_roothub_add_phy and at least breaks USB support on Raspberry Pi (bcm2835_defconfig): dwc2 20980000.usb: dwc2_hcd_init() FAILED, returning -38 dwc2: probe of 20980000.usb failed with error -38 Let usb_phy_roothub_alloc() return in case CONFIG_GENERIC_PHY is disabled to fix this issue (compilers might even be smart enough to optimize away most of the code within usb_phy_roothub_alloc and usb_phy_roothub_add_phy if CONFIG_GENERIC_PHY is disabled). All existing usb_phy_roothub_* functions are already NULL-safe, so no special handling is required there. Fixes: 07dbff0ddbd8 ("usb: core: add a wrapper for the USB PHYs on the HCD") Reported-by: Stefan Wahren Signed-off-by: Martin Blumenstingl Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/phy.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/usb/core/phy.c') diff --git a/drivers/usb/core/phy.c b/drivers/usb/core/phy.c index a39d9bb26a4f..9879767452a2 100644 --- a/drivers/usb/core/phy.c +++ b/drivers/usb/core/phy.c @@ -50,6 +50,9 @@ struct usb_phy_roothub *usb_phy_roothub_alloc(struct device *dev) struct usb_phy_roothub *phy_roothub; int i, num_phys, err; + if (!IS_ENABLED(CONFIG_GENERIC_PHY)) + return NULL; + num_phys = of_count_phandle_with_args(dev->of_node, "phys", "#phy-cells"); if (num_phys <= 0) -- cgit v1.2.3