spcom: abort any read() operation on SSR

Abort any read() operation to unlock the channel mutex.
On channel remote-disconnect notification, the local side should close
the channel.
However, open()/close()/read()/write() operations locks the channel mutex.
The glink rx-abort notification happens only after the remote-disconnect
notification, not as originally expected.

Change-Id: I77f8e6de6f1b5c447a3516380c51db9c7129d2f3
Signed-off-by: Amir Samuelov <amirs@codeaurora.org>

diff --git a/drivers/soc/qcom/spcom.c b/drivers/soc/qcom/spcom.c
index 5b3e6c3..e8ea998 100644 (file)
--- a/drivers/soc/qcom/spcom.c
+++ b/drivers/soc/qcom/spcom.c
@@ -272,6 +272,8 @@ static struct spcom_device *spcom_dev;
 static int spcom_create_channel_chardev(const char *name);
 static int spcom_open(struct spcom_channel *ch, unsigned int timeout_msec);
 static int spcom_close(struct spcom_channel *ch);
+static void spcom_notify_rx_abort(void *handle, const void *priv,
+                                 const void *pkt_priv);
 
 /**
  * spcom_is_ready() - driver is initialized and ready.
@@ -467,6 +469,13 @@ static void spcom_notify_state(void *handle, const void *priv, unsigned event)
                 * This may happen upon remote SSR.
                 */
                pr_err("GLINK_REMOTE_DISCONNECTED, ch [%s].\n", ch->name);
+
+               /*
+                * Abort any blocking read() operation.
+                * The glink notification might be after REMOTE_DISCONNECT.
+                */
+               spcom_notify_rx_abort(NULL, ch, NULL);
+
                /*
                 * after glink_close(),
                 * expecting notify GLINK_LOCAL_DISCONNECTED
@@ -515,7 +524,7 @@ static void spcom_notify_rx_abort(void *handle, const void *priv,
 
        pr_debug("ch [%s] pending rx aborted.\n", ch->name);
 
-       if (spcom_is_channel_connected(ch)) {
+       if (spcom_is_channel_connected(ch) && (!ch->rx_abort)) {
                ch->rx_abort = true;
                complete_all(&ch->rx_done);
        }
@@ -535,9 +544,9 @@ static void spcom_notify_tx_abort(void *handle, const void *priv,
 
        pr_debug("ch [%s] pending tx aborted.\n", ch->name);
 
-       if (spcom_is_channel_connected(ch)) {
-               complete_all(&ch->tx_done);
+       if (spcom_is_channel_connected(ch) && (!ch->tx_abort)) {
                ch->tx_abort = true;
+               complete_all(&ch->tx_done);
        }
 }