There is no need to take the rx->buf_lock in the the poll() function as all the underling calls made on objects in the rx->buf lirc_buffer object are protected by spinlocks.
Corrected a bad error return value in poll(): return POLLERR instead of -ENODEV. Added some comments to poll() for when, in the future, I forget what poll() and poll_wait() are supposed to do. Signed-off-by: Andy Walls <[email protected]> --- drivers/staging/lirc/lirc_zilog.c | 21 ++++++++++++++------- 1 files changed, 14 insertions(+), 7 deletions(-) diff --git a/drivers/staging/lirc/lirc_zilog.c b/drivers/staging/lirc/lirc_zilog.c index 720ef67..dfa6a42 100644 --- a/drivers/staging/lirc/lirc_zilog.c +++ b/drivers/staging/lirc/lirc_zilog.c @@ -985,19 +985,26 @@ static unsigned int poll(struct file *filep, poll_table *wait) unsigned int ret; dprintk("poll called\n"); - if (rx == NULL) - return -ENODEV; - mutex_lock(&rx->buf_lock); + if (rx == NULL) { + /* + * Revisit this, if our poll function ever reports writeable + * status for Tx + */ + dprintk("poll result = POLLERR\n"); + return POLLERR; + } + /* + * Add our lirc_buffer's wait_queue to the poll_table. A wake up on + * that buffer's wait queue indicates we may have a new poll status. + */ poll_wait(filep, &rx->buf.wait_poll, wait); - dprintk("poll result = %s\n", - lirc_buffer_empty(&rx->buf) ? "0" : "POLLIN|POLLRDNORM"); - + /* Indicate what ops could happen immediately without blocking */ ret = lirc_buffer_empty(&rx->buf) ? 0 : (POLLIN|POLLRDNORM); - mutex_unlock(&rx->buf_lock); + dprintk("poll result = %s\n", ret ? "POLLIN|POLLRDNORM" : 0); return ret; } -- 1.7.2.1 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
