diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-05-04 14:22:04 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-05-04 14:22:04 -0700 |
commit | 1c08232cfe5e68c6234305a3abb64d52d89c9ead (patch) | |
tree | ffba8b76685d26e719c20591e7b2b04468dd8507 /drivers/media/rc/imon.c | |
parent | 8db72a7d7268630e04ec285fbd3e90733b2eddf9 (diff) | |
parent | b730011061e2805a46b7291e708b6caaf2be6869 (diff) |
Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6
* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6:
[media] ngene: Fix CI data transfer regression Fix CI data transfer regression introduced by previous cleanup.
[media] v4l: make sure drivers supply a zeroed struct v4l2_subdev
[media] Missing frontend config for LME DM04/QQBOX
[media] rc_core: avoid kernel oops when rmmod saa7134
[media] imon: add conditional locking in change_protocol
[media] rc: show RC_TYPE_OTHER in sysfs
[media] ite-cir: modular build on ppc requires delay.h include
[media] mceusb: add Dell transceiver ID
Diffstat (limited to 'drivers/media/rc/imon.c')
-rw-r--r-- | drivers/media/rc/imon.c | 31 |
1 files changed, 27 insertions, 4 deletions
diff --git a/drivers/media/rc/imon.c b/drivers/media/rc/imon.c index ebd68edf5b2..8fc0f081b47 100644 --- a/drivers/media/rc/imon.c +++ b/drivers/media/rc/imon.c @@ -46,7 +46,7 @@ #define MOD_AUTHOR "Jarod Wilson <jarod@wilsonet.com>" #define MOD_DESC "Driver for SoundGraph iMON MultiMedia IR/Display" #define MOD_NAME "imon" -#define MOD_VERSION "0.9.2" +#define MOD_VERSION "0.9.3" #define DISPLAY_MINOR_BASE 144 #define DEVICE_NAME "lcd%d" @@ -460,8 +460,9 @@ static int display_close(struct inode *inode, struct file *file) } /** - * Sends a packet to the device -- this function must be called - * with ictx->lock held. + * Sends a packet to the device -- this function must be called with + * ictx->lock held, or its unlock/lock sequence while waiting for tx + * to complete can/will lead to a deadlock. */ static int send_packet(struct imon_context *ictx) { @@ -991,12 +992,21 @@ static void imon_touch_display_timeout(unsigned long data) * the iMON remotes, and those used by the Windows MCE remotes (which is * really just RC-6), but only one or the other at a time, as the signals * are decoded onboard the receiver. + * + * This function gets called two different ways, one way is from + * rc_register_device, for initial protocol selection/setup, and the other is + * via a userspace-initiated protocol change request, either by direct sysfs + * prodding or by something like ir-keytable. In the rc_register_device case, + * the imon context lock is already held, but when initiated from userspace, + * it is not, so we must acquire it prior to calling send_packet, which + * requires that the lock is held. */ static int imon_ir_change_protocol(struct rc_dev *rc, u64 rc_type) { int retval; struct imon_context *ictx = rc->priv; struct device *dev = ictx->dev; + bool unlock = false; unsigned char ir_proto_packet[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x86 }; @@ -1029,6 +1039,11 @@ static int imon_ir_change_protocol(struct rc_dev *rc, u64 rc_type) memcpy(ictx->usb_tx_buf, &ir_proto_packet, sizeof(ir_proto_packet)); + if (!mutex_is_locked(&ictx->lock)) { + unlock = true; + mutex_lock(&ictx->lock); + } + retval = send_packet(ictx); if (retval) goto out; @@ -1037,6 +1052,9 @@ static int imon_ir_change_protocol(struct rc_dev *rc, u64 rc_type) ictx->pad_mouse = false; out: + if (unlock) + mutex_unlock(&ictx->lock); + return retval; } @@ -2134,6 +2152,7 @@ static struct imon_context *imon_init_intf0(struct usb_interface *intf) goto rdev_setup_failed; } + mutex_unlock(&ictx->lock); return ictx; rdev_setup_failed: @@ -2205,6 +2224,7 @@ static struct imon_context *imon_init_intf1(struct usb_interface *intf, goto urb_submit_failed; } + mutex_unlock(&ictx->lock); return ictx; urb_submit_failed: @@ -2299,6 +2319,8 @@ static int __devinit imon_probe(struct usb_interface *interface, usb_set_intfdata(interface, ictx); if (ifnum == 0) { + mutex_lock(&ictx->lock); + if (product == 0xffdc && ictx->rf_device) { sysfs_err = sysfs_create_group(&interface->dev.kobj, &imon_rf_attr_group); @@ -2309,13 +2331,14 @@ static int __devinit imon_probe(struct usb_interface *interface, if (ictx->display_supported) imon_init_display(ictx, interface); + + mutex_unlock(&ictx->lock); } dev_info(dev, "iMON device (%04x:%04x, intf%d) on " "usb<%d:%d> initialized\n", vendor, product, ifnum, usbdev->bus->busnum, usbdev->devnum); - mutex_unlock(&ictx->lock); mutex_unlock(&driver_lock); return 0; |