platform/chrome: cros_ec_proto: Avoid -Wflex-array-member-not-at-end warnings

-Wflex-array-member-not-at-end was introduced in GCC-14, and we are
getting ready to enable it, globally.

Use the `DEFINE_RAW_FLEX()` helper for an on-stack definition of
a flexible structure where the size of the flexible-array member
is known at compile-time, and refactor the rest of the code,
accordingly.

So, with these changes, fix the following warnings:

drivers/platform/chrome/cros_ec_proto.c:143:40: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]
drivers/platform/chrome/cros_ec_proto.c:761:40: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/Z-adX1BB30dcSJ7x@kspp
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>

diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c
index 877b107fee4be055ea4d412449b647f753ba7740..586358fbf9819d539b21fbe947bced6c42e5991e 100644 (file)
--- a/drivers/platform/chrome/cros_ec_proto.c
+++ b/drivers/platform/chrome/cros_ec_proto.c
@@ -139,12 +139,10 @@ static int cros_ec_xfer_command(struct cros_ec_device *ec_dev, struct cros_ec_co
 
 static int cros_ec_wait_until_complete(struct cros_ec_device *ec_dev, uint32_t *result)
 {
-       struct {
-               struct cros_ec_command msg;
-               struct ec_response_get_comms_status status;
-       } __packed buf;
-       struct cros_ec_command *msg = &buf.msg;
-       struct ec_response_get_comms_status *status = &buf.status;
+       DEFINE_RAW_FLEX(struct cros_ec_command, msg, data,
+                       sizeof(struct ec_response_get_comms_status));
+       struct ec_response_get_comms_status *status =
+                       (struct ec_response_get_comms_status *)msg->data;
        int ret = 0, i;
 
        msg->version = 0;
@@ -757,16 +755,13 @@ static int get_next_event_xfer(struct cros_ec_device *ec_dev,
 
 static int get_next_event(struct cros_ec_device *ec_dev)
 {
-       struct {
-               struct cros_ec_command msg;
-               struct ec_response_get_next_event_v3 event;
-       } __packed buf;
-       struct cros_ec_command *msg = &buf.msg;
-       struct ec_response_get_next_event_v3 *event = &buf.event;
+       DEFINE_RAW_FLEX(struct cros_ec_command, msg, data,
+                       sizeof(struct ec_response_get_next_event_v3));
+       struct ec_response_get_next_event_v3 *event =
+                       (struct ec_response_get_next_event_v3 *)msg->data;
        int cmd_version = ec_dev->mkbp_event_supported - 1;
        u32 size;
 
-       memset(msg, 0, sizeof(*msg));
        if (ec_dev->suspended) {
                dev_dbg(ec_dev->dev, "Device suspended.\n");
                return -EHOSTDOWN;