[PATCH 2/2] firmware: arm_scmi: Add compatibility checks for shmem node

Sudeep Holla
2021-06-01T22:55:56Z

The shared memory node used for communication between the firmware and
the OS should be compatible with "arm,scmi-shmem". Add the check for the
same while parsing the node before fetching the memory regions.

Cc: Cristian Marussi <cristian.marussi@arm.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Jim Quinlan <jim2101024@gmail.com>
Cc: Etienne Carriere <etienne.carriere@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
---
drivers/firmware/arm_scmi/mailbox.c | 3 +++
drivers/firmware/arm_scmi/smc.c | 3 +++
2 files changed, 6 insertions(+)

diff --git a/drivers/firmware/arm_scmi/mailbox.c b/drivers/firmware/arm_scmi/mailbox.c
index 4626404be541..e3dcb58314ae 100644
--- a/drivers/firmware/arm_scmi/mailbox.c
+++ b/drivers/firmware/arm_scmi/mailbox.c
@@ -69,6 +69,9 @@ static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
return -ENOMEM;

shmem = of_parse_phandle(cdev->of_node, "shmem", idx);
+ if (!of_device_is_compatible(shmem, "arm,scmi-shmem"))
+ return -ENXIO;
+
ret = of_address_to_resource(shmem, 0, &res);
of_node_put(shmem);
if (ret) {
diff --git a/drivers/firmware/arm_scmi/smc.c b/drivers/firmware/arm_scmi/smc.c
index fcbe2677f84b..78198ef94438 100644
--- a/drivers/firmware/arm_scmi/smc.c
+++ b/drivers/firmware/arm_scmi/smc.c
@@ -76,6 +76,9 @@ static int smc_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
return -ENOMEM;

np = of_parse_phandle(cdev->of_node, "shmem", 0);
+ if (!of_device_is_compatible(shmem, "arm,scmi-shmem"))
+ return -ENXIO;
+
ret = of_address_to_resource(np, 0, &res);
of_node_put(np);
if (ret) {
--
2.25.1