On Jan 19, 2026 at 11:18:27 +0000, Jonathan Cameron wrote:

On Wed, 14 Jan 2026 11:46:05 +0000
Cristian Marussi [off-list ref] wrote:

quoted

Add a common definition of SCMI_MAX_PROTOCOLS and use it all over the
SCMI stack.

Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>

Hi Cristian,

Mention the introduction of SCMI_PROTOCOL_LAST in the patch description
and probably say why it takes that value (which is much less than
the SCMI_MAX_PROTOCOLS value).

Rather I wonder why even add it? Is it just like a documentation/ marker
or is some other usage even planned for it?

Jonathan

quoted

---
 drivers/firmware/arm_scmi/notify.c | 4 +---
 include/linux/scmi_protocol.h      | 3 +++
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/firmware/arm_scmi/notify.c b/drivers/firmware/arm_scmi/notify.c
index dee9f238f6fd..78e9e27dc9ec 100644
--- a/drivers/firmware/arm_scmi/notify.c
+++ b/drivers/firmware/arm_scmi/notify.c

@@ -94,8 +94,6 @@
 #include "common.h"
 #include "notify.h"
 
-#define SCMI_MAX_PROTO		256
-
 #define PROTO_ID_MASK		GENMASK(31, 24)
 #define EVT_ID_MASK		GENMASK(23, 16)
 #define SRC_ID_MASK		GENMASK(15, 0)

@@ -1673,7 +1671,7 @@ int scmi_notification_init(struct scmi_handle *handle)
 	ni->gid = gid;
 	ni->handle = handle;
 
-	ni->registered_protocols = devm_kcalloc(handle->dev, SCMI_MAX_PROTO,
+	ni->registered_protocols = devm_kcalloc(handle->dev, SCMI_MAX_PROTOCOLS,
 						sizeof(char *), GFP_KERNEL);
 	if (!ni->registered_protocols)
 		goto err;

diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h
index aafaac1496b0..c6efe4f371ac 100644
--- a/include/linux/scmi_protocol.h
+++ b/include/linux/scmi_protocol.h

@@ -926,8 +926,11 @@ enum scmi_std_protocol {
 	SCMI_PROTOCOL_VOLTAGE = 0x17,
 	SCMI_PROTOCOL_POWERCAP = 0x18,
 	SCMI_PROTOCOL_PINCTRL = 0x19,
+	SCMI_PROTOCOL_LAST = 0x7f,
 };
 
+#define SCMI_MAX_PROTOCOLS	256
+
 enum scmi_system_events {
 	SCMI_SYSTEM_SHUTDOWN,
 	SCMI_SYSTEM_COLDRESET,

-- 
Best regards,
Dhruva Gole
Texas Instruments Incorporated