mailbox: tegra: avoid resume NULL mailboxes

If Tegra HSP device tree does not have 'shared irqs',
mailboxes pointer is NULL. Add non-NULL HSP mailboxes
check in resume callback before tegra_hsp_mailbox_startup()
call and prevent NULL pointer exception.

Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/mailbox/tegra-hsp.c b/drivers/mailbox/tegra-hsp.c
index 91e223e05e1d..4c5ba35d48d4 100644
--- a/drivers/mailbox/tegra-hsp.c
+++ b/drivers/mailbox/tegra-hsp.c
@@ -782,11 +782,13 @@ static int __maybe_unused tegra_hsp_resume(struct device *dev)
                         tegra_hsp_doorbell_startup(db->channel.chan);
         }
 
-        for (i = 0; i < hsp->num_sm; i++) {
-                struct tegra_hsp_mailbox *mb = &hsp->mailboxes[i];
+        if (hsp->mailboxes) {
+                for (i = 0; i < hsp->num_sm; i++) {
+                        struct tegra_hsp_mailbox *mb = &hsp->mailboxes[i];
 
-                if (mb->channel.chan->cl)
-                        tegra_hsp_mailbox_startup(mb->channel.chan);
+                        if (mb->channel.chan->cl)
+                                tegra_hsp_mailbox_startup(mb->channel.chan);
+                }
         }
 
         return 0;