[U-Boot] [PATCH 01/24] usb: add device connection/disconnection detection

Simon Glass
2015-05-04T17:30:54Z

From: Vincent Palatin <vpalatin@chromium.org>

Provide a function to detect USB device insertion/removal in order to
avoid having to do USB enumeration in a tight loop when trying to detect
peripheral hotplugging.

Signed-off-by: Vincent Palatin <vpalatin@chromium.org>

Reviewed-by: Stefan Reinauer <reinauer@chromium.org>
Tested-by: Stefan Reinauer <reinauer@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
---

common/usb.c | 26 ++++++++++++++++++++++++++
common/usb_hub.c | 2 +-
include/usb.h | 2 ++
3 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/common/usb.c b/common/usb.c
index a4820d3..bde8f31 100644
--- a/common/usb.c
+++ b/common/usb.c
@@ -148,6 +148,32 @@ int usb_stop(void)
return 0;
}

+/******************************************************************************
+ * Detect if a USB device has been plugged or unplugged.
+ */
+int usb_detect_change(void)
+{
+ int i, j;
+ int change = 0;
+
+ for (j = 0; j < USB_MAX_DEVICE; j++) {
+ for (i = 0; i < usb_dev[j].maxchild; i++) {
+ struct usb_port_status status;
+
+ if (usb_get_port_status(&usb_dev[j], i + 1,
+ &status) < 0)
+ /* USB request failed */
+ continue;
+
+ if (le16_to_cpu(status.wPortChange) &
+ USB_PORT_STAT_C_CONNECTION)
+ change++;
+ }
+ }
+
+ return change;
+}
+
/*
* disables the asynch behaviour of the control message. This is used for data
* transfers that uses the exclusiv access to the control and bulk messages.
diff --git a/common/usb_hub.c b/common/usb_hub.c
index c9be530..bbed1c8 100644
--- a/common/usb_hub.c
+++ b/common/usb_hub.c
@@ -79,7 +79,7 @@ static int usb_get_hub_status(struct usb_device *dev, void *data)
data, sizeof(struct usb_hub_status), USB_CNTL_TIMEOUT);
}

-static int usb_get_port_status(struct usb_device *dev, int port, void *data)
+int usb_get_port_status(struct usb_device *dev, int port, void *data)
{
return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port,
diff --git a/include/usb.h b/include/usb.h
index 1984e8f..25dddb8 100644
--- a/include/usb.h
+++ b/include/usb.h
@@ -265,6 +265,7 @@ int usb_kbd_deregister(int force);
/* routines */
int usb_init(void); /* initialize the USB Controller */
int usb_stop(void); /* stop the USB Controller */
+int usb_detect_change(void); /* detect if a USB device has been (un)plugged */

int usb_set_protocol(struct usb_device *dev, int ifnum, int protocol);
@@ -290,6 +291,7 @@ int usb_get_class_descriptor(struct usb_device *dev, int ifnum,
int usb_clear_halt(struct usb_device *dev, int pipe);
int usb_string(struct usb_device *dev, int index, char *buf, size_t size);
int usb_set_interface(struct usb_device *dev, int interface, int alternate);
+int usb_get_port_status(struct usb_device *dev, int port, void *data);

/* big endian -> little endian conversion */
/* some CPUs are already little endian e.g. the ARM920T */
--
2.2.0.rc0.207.ga3a616c