[RFC v4 11/14] EXAMPLE CODE: usb: port: Parse pwrseq phandle from Device Tree
From: Krzysztof Kozlowski <hidden>
Date: 2016-06-09 09:45:30
Also in:
linux-arm-kernel, linux-fbdev, linux-mmc, linux-pm, linux-samsung-soc, lkml
Subsystem:
the rest, usb subsystem · Maintainers:
Linus Torvalds, Greg Kroah-Hartman
Parse usb-pwrseq property from Device Tree to get the phandle to pwrseq device. The pwrseq device will be used by USB hub to cycle the power before activating ports. Signed-off-by: Krzysztof Kozlowski <redacted> --- drivers/usb/core/hub.h | 3 +++ drivers/usb/core/port.c | 16 ++++++++++++++++ 2 files changed, 19 insertions(+)
diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h
index 34c1a7e22aae..68ca89780d26 100644
--- a/drivers/usb/core/hub.h
+++ b/drivers/usb/core/hub.h@@ -24,6 +24,8 @@ #include <linux/usb/hcd.h> #include "usb.h" +struct pwrseq; + struct usb_hub { struct device *intfdev; /* the "interface" device */ struct usb_device *hdev;
@@ -101,6 +103,7 @@ struct usb_port { struct usb_dev_state *port_owner; struct usb_port *peer; struct dev_pm_qos_request *req; + struct pwrseq *pwrseq; enum usb_port_connect_type connect_type; usb_port_location_t location; struct mutex status_lock;
diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
index 460c855be0d0..4fce0250179c 100644
--- a/drivers/usb/core/port.c
+++ b/drivers/usb/core/port.c@@ -18,6 +18,8 @@ #include <linux/slab.h> #include <linux/pm_qos.h> +#include <linux/pwrseq.h> +#include <linux/usb/of.h> #include "hub.h"
@@ -526,6 +528,15 @@ int usb_hub_create_port_device(struct usb_hub *hub, int port1) return retval; } + port_dev->dev.of_node = usb_of_get_child_node(hdev->dev.parent->of_node, + port1); + port_dev->pwrseq = pwrseq_alloc(&port_dev->dev, "usb-pwrseq"); + if (IS_ERR(port_dev->pwrseq)) { + retval = PTR_ERR(port_dev->pwrseq); + device_unregister(&port_dev->dev); + return retval; + } + find_and_link_peer(hub, port1); /*
@@ -567,8 +578,13 @@ void usb_hub_remove_port_device(struct usb_hub *hub, int port1) struct usb_port *port_dev = hub->ports[port1 - 1]; struct usb_port *peer; + pwrseq_power_off(port_dev->pwrseq); + peer = port_dev->peer; if (peer) unlink_peers(port_dev, peer); + + pwrseq_free(port_dev->pwrseq); + port_dev->pwrseq = NULL; device_unregister(&port_dev->dev); }
--
1.9.1