From 09092787e0cf66e705b0d744f5f0c3b2b6495559 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Sat, 14 Dec 2013 08:28:36 -0300 Subject: [media] saa6588: add support for non-blocking mode saa6588 always blocked while waiting for data, even if the filehandle was in non-blocking mode. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/i2c/saa6588.c | 45 +++++++++++++++++++++++++-------------------- 1 file changed, 25 insertions(+), 20 deletions(-) (limited to 'drivers/media/i2c') diff --git a/drivers/media/i2c/saa6588.c b/drivers/media/i2c/saa6588.c index 21cf940f5ea..2960b5a8362 100644 --- a/drivers/media/i2c/saa6588.c +++ b/drivers/media/i2c/saa6588.c @@ -150,14 +150,14 @@ static inline struct saa6588 *to_saa6588(struct v4l2_subdev *sd) /* ---------------------------------------------------------------------- */ -static int block_to_user_buf(struct saa6588 *s, unsigned char __user *user_buf) +static bool block_from_buf(struct saa6588 *s, unsigned char *buf) { int i; if (s->rd_index == s->wr_index) { if (debug > 2) dprintk(PREFIX "Read: buffer empty.\n"); - return 0; + return false; } if (debug > 2) { @@ -166,8 +166,7 @@ static int block_to_user_buf(struct saa6588 *s, unsigned char __user *user_buf) dprintk("0x%02x ", s->buffer[i]); } - if (copy_to_user(user_buf, &s->buffer[s->rd_index], 3)) - return -EFAULT; + memcpy(buf, &s->buffer[s->rd_index], 3); s->rd_index += 3; if (s->rd_index >= s->buf_size) @@ -177,22 +176,22 @@ static int block_to_user_buf(struct saa6588 *s, unsigned char __user *user_buf) if (debug > 2) dprintk("%d blocks total.\n", s->block_count); - return 1; + return true; } static void read_from_buf(struct saa6588 *s, struct saa6588_command *a) { - unsigned long flags; - unsigned char __user *buf_ptr = a->buffer; - unsigned int i; + unsigned char buf[3]; + unsigned long flags; unsigned int rd_blocks; + unsigned int i; a->result = 0; if (!a->buffer) return; - while (!s->data_available_for_read) { + while (!a->nonblocking && !s->data_available_for_read) { int ret = wait_event_interruptible(s->read_queue, s->data_available_for_read); if (ret == -ERESTARTSYS) { @@ -201,24 +200,31 @@ static void read_from_buf(struct saa6588 *s, struct saa6588_command *a) } } - spin_lock_irqsave(&s->lock, flags); rd_blocks = a->block_count; + spin_lock_irqsave(&s->lock, flags); if (rd_blocks > s->block_count) rd_blocks = s->block_count; + spin_unlock_irqrestore(&s->lock, flags); - if (!rd_blocks) { - spin_unlock_irqrestore(&s->lock, flags); + if (!rd_blocks) return; - } for (i = 0; i < rd_blocks; i++) { - if (block_to_user_buf(s, buf_ptr)) { - buf_ptr += 3; - a->result++; - } else + bool got_block; + + spin_lock_irqsave(&s->lock, flags); + got_block = block_from_buf(s, buf); + spin_unlock_irqrestore(&s->lock, flags); + if (!got_block) break; + if (copy_to_user(buf_ptr, buf, 3)) { + a->result = -EFAULT; + return; + } + buf_ptr += 3; + a->result += 3; } - a->result *= 3; + spin_lock_irqsave(&s->lock, flags); s->data_available_for_read = (s->block_count > 0); spin_unlock_irqrestore(&s->lock, flags); } @@ -408,9 +414,8 @@ static long saa6588_ioctl(struct v4l2_subdev *sd, unsigned int cmd, void *arg) /* --- poll() for /dev/radio --- */ case SAA6588_CMD_POLL: a->result = 0; - if (s->data_available_for_read) { + if (s->data_available_for_read) a->result |= POLLIN | POLLRDNORM; - } poll_wait(a->instance, &s->read_queue, a->event_list); break; -- cgit v1.2.3-70-g09d2