msm: smd_pkt: Allow multiple users of an SMD_PKT device
Add the usage reference count for every SMD_PKT device. Update the
sequence of operations in device open & close calls. This will enable
multiple user-space users of a SMD_PKT device.
Change-Id: Ic11d0c2e6908f1d82f7aef6a99a0239a92358814
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org>
diff --git a/arch/arm/mach-msm/smd_pkt.c b/arch/arm/mach-msm/smd_pkt.c
index 5962d71..30acebf 100644
--- a/arch/arm/mach-msm/smd_pkt.c
+++ b/arch/arm/mach-msm/smd_pkt.c
@@ -65,6 +65,7 @@
wait_queue_head_t ch_opened_wait_queue;
int i;
+ int ref_cnt;
int blocking_write;
int is_open;
@@ -270,6 +271,7 @@
if (!smd_pkt_devp)
return -EINVAL;
+ mutex_lock(&smd_pkt_devp->ch_lock);
switch (cmd) {
case TIOCMGET:
D_STATUS("%s TIOCMGET command on smd_pkt_dev id:%d\n",
@@ -288,6 +290,7 @@
pr_err("%s: Unrecognized ioctl command %d\n", __func__, cmd);
ret = -1;
}
+ mutex_unlock(&smd_pkt_devp->ch_lock);
return ret;
}
@@ -867,9 +870,12 @@
smd_pkt_devp->ch_size =
smd_write_avail(smd_pkt_devp->ch);
r = 0;
+ smd_pkt_devp->ref_cnt++;
D_STATUS("Finished %s on smd_pkt_dev id:%d\n",
__func__, smd_pkt_devp->i);
}
+ } else {
+ smd_pkt_devp->ref_cnt++;
}
release_pil:
if (peripheral && (r < 0))
@@ -902,12 +908,14 @@
D_STATUS("Begin %s on smd_pkt_dev id:%d\n",
__func__, smd_pkt_devp->i);
- clean_and_signal(smd_pkt_devp);
-
mutex_lock(&smd_pkt_devp->ch_lock);
mutex_lock(&smd_pkt_devp->rx_lock);
mutex_lock(&smd_pkt_devp->tx_lock);
- if (smd_pkt_devp->ch != 0) {
+ if (smd_pkt_devp->ref_cnt > 0)
+ smd_pkt_devp->ref_cnt--;
+
+ if (smd_pkt_devp->ch != 0 && smd_pkt_devp->ref_cnt == 0) {
+ clean_and_signal(smd_pkt_devp);
r = smd_close(smd_pkt_devp->ch);
smd_pkt_devp->ch = 0;
smd_pkt_devp->blocking_write = 0;
@@ -916,15 +924,15 @@
smd_pkt_devp->driver.probe = NULL;
if (smd_pkt_devp->pil)
pil_put(smd_pkt_devp->pil);
+ smd_pkt_devp->has_reset = 0;
+ smd_pkt_devp->do_reset_notification = 0;
+ smd_pkt_devp->wakelock_locked = 0;
+ wake_lock_destroy(&smd_pkt_devp->pa_wake_lock);
}
mutex_unlock(&smd_pkt_devp->tx_lock);
mutex_unlock(&smd_pkt_devp->rx_lock);
mutex_unlock(&smd_pkt_devp->ch_lock);
- smd_pkt_devp->has_reset = 0;
- smd_pkt_devp->do_reset_notification = 0;
- smd_pkt_devp->wakelock_locked = 0;
- wake_lock_destroy(&smd_pkt_devp->pa_wake_lock);
D_STATUS("Finished %s on smd_pkt_dev id:%d\n",
__func__, smd_pkt_devp->i);