firmware: arm_scmi: Fix NULL pointer dereference in mailbox_chan_free

[linux-2.6-microblaze.git] / drivers / firmware / arm_scmi / mailbox.c

diff --git a/drivers/firmware/arm_scmi/mailbox.c b/drivers/firmware/arm_scmi/mailbox.c
index 73077bb..4626404 100644 (file)
--- a/drivers/firmware/arm_scmi/mailbox.c
+++ b/drivers/firmware/arm_scmi/mailbox.c
@@ -110,7 +110,7 @@ static int mailbox_chan_free(int id, void *p, void *data)
        struct scmi_chan_info *cinfo = p;
        struct scmi_mailbox *smbox = cinfo->transport_info;
 
-       if (!IS_ERR(smbox->chan)) {
+       if (smbox && !IS_ERR(smbox->chan)) {
                mbox_free_channel(smbox->chan);
                cinfo->transport_info = NULL;
                smbox->chan = NULL;
@@ -158,6 +158,21 @@ static void mailbox_fetch_response(struct scmi_chan_info *cinfo,
        shmem_fetch_response(smbox->shmem, xfer);
 }
 
+static void mailbox_fetch_notification(struct scmi_chan_info *cinfo,
+                                      size_t max_len, struct scmi_xfer *xfer)
+{
+       struct scmi_mailbox *smbox = cinfo->transport_info;
+
+       shmem_fetch_notification(smbox->shmem, max_len, xfer);
+}
+
+static void mailbox_clear_channel(struct scmi_chan_info *cinfo)
+{
+       struct scmi_mailbox *smbox = cinfo->transport_info;
+
+       shmem_clear_channel(smbox->shmem);
+}
+
 static bool
 mailbox_poll_done(struct scmi_chan_info *cinfo, struct scmi_xfer *xfer)
 {
@@ -166,13 +181,15 @@ mailbox_poll_done(struct scmi_chan_info *cinfo, struct scmi_xfer *xfer)
        return shmem_poll_done(smbox->shmem, xfer);
 }
 
-static struct scmi_transport_ops scmi_mailbox_ops = {
+static const struct scmi_transport_ops scmi_mailbox_ops = {
        .chan_available = mailbox_chan_available,
        .chan_setup = mailbox_chan_setup,
        .chan_free = mailbox_chan_free,
        .send_message = mailbox_send_message,
        .mark_txdone = mailbox_mark_txdone,
        .fetch_response = mailbox_fetch_response,
+       .fetch_notification = mailbox_fetch_notification,
+       .clear_channel = mailbox_clear_channel,
        .poll_done = mailbox_poll_done,
 };