[PATCH v14 4/7] usb: core: add power sequence handling for USB devices
From: Peter Chen <hidden>
Date: 2017-06-05 06:55:47
Also in:
linux-devicetree, linux-pm, lkml
On Thu, May 18, 2017 at 08:49:00AM +0800, Peter Chen wrote:
Some hard-wired USB devices need to do power sequence to let the device work normally, the typical power sequence like: enable USB PHY clock, toggle reset pin, etc. But current Linux USB driver lacks of such code to do it, it may cause some hard-wired USB devices works abnormal or can't be recognized by controller at all. In this patch, it calls power sequence library APIs to finish the power sequence events. It will do power on sequence at hub's probe for all devices under this hub (includes root hub). At hub_disconnect, it will do power off sequence which is at powered on list.
Greg, Alan, would you please help on reviewing it? It seems Rafael is waiting for USB MAINTAINERS's comments or ack. It resolves some USB HUB issues for several persons. Peter
quoted hunk ↗ jump to hunk
Signed-off-by: Peter Chen <redacted> Tested-by Joshua Clayton [off-list ref] Tested-by: Maciej S. Szmigiero <redacted> Reviewed-by: Vaibhav Hiremath <hvaibhav.linux@gmail.com> --- drivers/usb/Kconfig | 1 + drivers/usb/core/hub.c | 49 +++++++++++++++++++++++++++++++++++++++++++++---- drivers/usb/core/hub.h | 1 + 3 files changed, 47 insertions(+), 4 deletions(-)diff --git a/drivers/usb/Kconfig b/drivers/usb/Kconfig index 939a63b..b6f626e 100644 --- a/drivers/usb/Kconfig +++ b/drivers/usb/Kconfig@@ -39,6 +39,7 @@ config USB tristate "Support for Host-side USB" depends on USB_ARCH_HAS_HCD select USB_COMMON + select POWER_SEQUENCE select NLS # for UTF-8 strings ---help--- Universal Serial Bus (USB) is a specification for a serial busdiff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 9dca59e..7a67296 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c@@ -28,6 +28,7 @@ #include <linux/mutex.h> #include <linux/random.h> #include <linux/pm_qos.h> +#include <linux/power/pwrseq.h> #include <linux/uaccess.h> #include <asm/byteorder.h>@@ -1619,6 +1620,7 @@ static void hub_disconnect(struct usb_interface *intf) hub->error = 0; hub_quiesce(hub, HUB_DISCONNECT); + of_pwrseq_off_list(&hub->pwrseq_on_list); mutex_lock(&usb_port_peer_mutex); /* Avoid races with recursively_mark_NOTATTACHED() */@@ -1646,12 +1648,42 @@ static void hub_disconnect(struct usb_interface *intf) kref_put(&hub->kref, hub_release); } +#ifdef CONFIG_OF +static int hub_of_pwrseq_on(struct usb_hub *hub) +{ + struct device *parent; + struct usb_device *hdev = hub->hdev; + struct device_node *np; + int ret; + + if (hdev->parent) + parent = &hdev->dev; + else + parent = bus_to_hcd(hdev->bus)->self.sysdev; + + for_each_child_of_node(parent->of_node, np) { + ret = of_pwrseq_on_list(np, &hub->pwrseq_on_list); + /* Maybe no power sequence library is chosen */ + if (ret && ret != -ENOENT) + return ret; + } + + return 0; +} +#else +static int hub_of_pwrseq_on(struct usb_hub *hub) +{ + return 0; +} +#endif + static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id) { struct usb_host_interface *desc; struct usb_endpoint_descriptor *endpoint; struct usb_device *hdev; struct usb_hub *hub; + int ret = -ENODEV; desc = intf->cur_altsetting; hdev = interface_to_usbdev(intf);@@ -1756,6 +1788,7 @@ static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id) INIT_DELAYED_WORK(&hub->leds, led_work); INIT_DELAYED_WORK(&hub->init_work, NULL); INIT_WORK(&hub->events, hub_event); + INIT_LIST_HEAD(&hub->pwrseq_on_list); usb_get_intf(intf); usb_get_dev(hdev);@@ -1769,11 +1802,14 @@ static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id) if (id->driver_info & HUB_QUIRK_CHECK_PORT_AUTOSUSPEND) hub->quirk_check_port_auto_suspend = 1; - if (hub_configure(hub, endpoint) >= 0) - return 0; + if (hub_configure(hub, endpoint) >= 0) { + ret = hub_of_pwrseq_on(hub); + if (!ret) + return 0; + } hub_disconnect(intf); - return -ENODEV; + return ret; } static int@@ -3593,14 +3629,19 @@ static int hub_suspend(struct usb_interface *intf, pm_message_t msg) /* stop hub_wq and related activity */ hub_quiesce(hub, HUB_SUSPEND); - return 0; + return pwrseq_suspend_list(&hub->pwrseq_on_list); } static int hub_resume(struct usb_interface *intf) { struct usb_hub *hub = usb_get_intfdata(intf); + int ret; dev_dbg(&intf->dev, "%s\n", __func__); + ret = pwrseq_resume_list(&hub->pwrseq_on_list); + if (ret) + return ret; + hub_activate(hub, HUB_RESUME); return 0; }diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h index 34c1a7e..cd86f91 100644 --- a/drivers/usb/core/hub.h +++ b/drivers/usb/core/hub.h@@ -78,6 +78,7 @@ struct usb_hub { struct delayed_work init_work; struct work_struct events; struct usb_port **ports; + struct list_head pwrseq_on_list; /* powered pwrseq node list */ }; /**-- 2.7.4 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel at lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
-- Best Regards, Peter Chen