aboutsummaryrefslogtreecommitdiff
path: root/drivers/media/rc/mceusb.c
diff options
context:
space:
mode:
authorA Sun2017-03-26 15:28:08 -0300
committerMauro Carvalho Chehab2017-06-06 08:56:33 -0300
commita06854a600f6ccb72f097d86a44688949b867906 (patch)
tree96ccbc8fe5877f7da972f7acf9b570b6c00ebf27 /drivers/media/rc/mceusb.c
parent2aa1bd1c1ca82f57f3e6967d34c8c985dcc22f48 (diff)
[media] mceusb: RX -EPIPE (urb status = -32) lockup failure fix
RX -EPIPE failure with infinite loop and flooding of [ 2851.966506] mceusb 1-1.2:1.0: Error: urb status = -32 log message at 8000 messages per second. Bug trigger appears to be normal, but heavy, IR receiver use. Driver and Linux host become unusable after error. Also seen at https://sourceforge.net/p/lirc/mailman/message/34886165/ Fix: Message reports RX usb halt (stall) condition requiring usb_clear_halt() call in non-interrupt context to recover. Add driver workqueue call to perform this recovery based on method in use for the usbnet device driver. Signed-off-by: A Sun <as1033x@comcast.net> Signed-off-by: Sean Young <sean@mess.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Diffstat (limited to 'drivers/media/rc/mceusb.c')
-rw-r--r--drivers/media/rc/mceusb.c74
1 files changed, 73 insertions, 1 deletions
diff --git a/drivers/media/rc/mceusb.c b/drivers/media/rc/mceusb.c
index 17e75cd8399a..1e08c7dc0e82 100644
--- a/drivers/media/rc/mceusb.c
+++ b/drivers/media/rc/mceusb.c
@@ -36,12 +36,13 @@
#include <linux/device.h>
#include <linux/module.h>
#include <linux/slab.h>
+#include <linux/workqueue.h>
#include <linux/usb.h>
#include <linux/usb/input.h>
#include <linux/pm_wakeup.h>
#include <media/rc-core.h>
-#define DRIVER_VERSION "1.92"
+#define DRIVER_VERSION "1.93"
#define DRIVER_AUTHOR "Jarod Wilson <jarod@redhat.com>"
#define DRIVER_DESC "Windows Media Center Ed. eHome Infrared Transceiver " \
"device driver"
@@ -416,6 +417,7 @@ struct mceusb_dev {
/* usb */
struct usb_device *usbdev;
struct urb *urb_in;
+ unsigned int pipe_in;
struct usb_endpoint_descriptor *usb_ep_out;
/* buffers and dma */
@@ -453,6 +455,16 @@ struct mceusb_dev {
u8 num_rxports; /* number of receive sensors */
u8 txports_cabled; /* bitmask of transmitters with cable */
u8 rxports_active; /* bitmask of active receive sensors */
+
+ /*
+ * support for async error handler mceusb_deferred_kevent()
+ * where usb_clear_halt(), usb_reset_configuration(),
+ * usb_reset_device(), etc. must be done in process context
+ */
+ struct work_struct kevent;
+ unsigned long kevent_flags;
+# define EVENT_TX_HALT 0
+# define EVENT_RX_HALT 1
};
/* MCE Device Command Strings, generally a port and command pair */
@@ -686,6 +698,21 @@ static void mceusb_dev_printdata(struct mceusb_dev *ir, char *buf,
#endif
}
+/*
+ * Schedule work that can't be done in interrupt handlers
+ * (mceusb_dev_recv() and mce_async_callback()) nor tasklets.
+ * Invokes mceusb_deferred_kevent() for recovering from
+ * error events specified by the kevent bit field.
+ */
+static void mceusb_defer_kevent(struct mceusb_dev *ir, int kevent)
+{
+ set_bit(kevent, &ir->kevent_flags);
+ if (!schedule_work(&ir->kevent))
+ dev_err(ir->dev, "kevent %d may have been dropped", kevent);
+ else
+ dev_dbg(ir->dev, "kevent %d scheduled", kevent);
+}
+
static void mce_async_callback(struct urb *urb)
{
struct mceusb_dev *ir;
@@ -1053,6 +1080,11 @@ static void mceusb_dev_recv(struct urb *urb)
return;
case -EPIPE:
+ dev_err(ir->dev, "Error: urb status = %d (RX HALT)",
+ urb->status);
+ mceusb_defer_kevent(ir, EVENT_RX_HALT);
+ return;
+
default:
dev_err(ir->dev, "Error: urb status = %d", urb->status);
break;
@@ -1171,6 +1203,37 @@ static void mceusb_flash_led(struct mceusb_dev *ir)
mce_async_out(ir, FLASH_LED, sizeof(FLASH_LED));
}
+/*
+ * Workqueue function
+ * for resetting or recovering device after occurrence of error events
+ * specified in ir->kevent bit field.
+ * Function runs (via schedule_work()) in non-interrupt context, for
+ * calls here (such as usb_clear_halt()) requiring non-interrupt context.
+ */
+static void mceusb_deferred_kevent(struct work_struct *work)
+{
+ struct mceusb_dev *ir =
+ container_of(work, struct mceusb_dev, kevent);
+ int status;
+
+ if (test_bit(EVENT_RX_HALT, &ir->kevent_flags)) {
+ usb_unlink_urb(ir->urb_in);
+ status = usb_clear_halt(ir->usbdev, ir->pipe_in);
+ if (status < 0) {
+ dev_err(ir->dev, "rx clear halt error %d",
+ status);
+ return;
+ }
+ clear_bit(EVENT_RX_HALT, &ir->kevent_flags);
+ status = usb_submit_urb(ir->urb_in, GFP_KERNEL);
+ if (status < 0) {
+ dev_err(ir->dev, "rx unhalt submit urb error %d",
+ status);
+ return;
+ }
+ }
+}
+
static struct rc_dev *mceusb_init_rc_dev(struct mceusb_dev *ir)
{
struct usb_device *udev = ir->usbdev;
@@ -1304,6 +1367,7 @@ static int mceusb_dev_probe(struct usb_interface *intf,
if (!ir)
goto mem_alloc_fail;
+ ir->pipe_in = pipe;
ir->buf_in = usb_alloc_coherent(dev, maxp, GFP_ATOMIC, &ir->dma_in);
if (!ir->buf_in)
goto buf_in_alloc_fail;
@@ -1333,6 +1397,12 @@ static int mceusb_dev_probe(struct usb_interface *intf,
snprintf(name + strlen(name), sizeof(name) - strlen(name),
" %s", buf);
+ /*
+ * Initialize async USB error handler before registering
+ * or activating any mceusb RX and TX functions
+ */
+ INIT_WORK(&ir->kevent, mceusb_deferred_kevent);
+
ir->rc = mceusb_init_rc_dev(ir);
if (!ir->rc)
goto rc_dev_fail;
@@ -1386,6 +1456,7 @@ static int mceusb_dev_probe(struct usb_interface *intf,
/* Error-handling path */
rc_dev_fail:
+ cancel_work_sync(&ir->kevent);
usb_put_dev(ir->usbdev);
usb_kill_urb(ir->urb_in);
usb_free_urb(ir->urb_in);
@@ -1411,6 +1482,7 @@ static void mceusb_dev_disconnect(struct usb_interface *intf)
return;
ir->usbdev = NULL;
+ cancel_work_sync(&ir->kevent);
rc_unregister_device(ir->rc);
usb_kill_urb(ir->urb_in);
usb_free_urb(ir->urb_in);