Add LIGHTBAR_CMD_VERSION command to detect lightbar features.stabilize-4636.B

Most systems don't have a lightbar. Those that do need a way to detect that
one exists. That's easily done by just sending a EC_CMD_LIGHTBAR_CMD command
to the EC and checking the result. If the response is
EC_RES_INVALID_COMMAND, there isn't a lightbar.

But what .cmd value should we use in struct ec_params_lightbar? Future
lightbar implementations (if any), could remove existing functions or add
new ones, so there isn't a safe choice.

This change adds a LIGHTBAR_CMD_VERSION operation to determine if any new
implementation exists. Future systems should return some useful information
in response to this command. Existing systems will return
EC_RES_INVALID_PARAM, which is enough to distinguish them.

BUG=chromium:239205
BRANCH=none
TEST=manual

make BOARD=link
make BOARD=link runtests

There are no user-visible changes in functionality to anything.

Change-Id: Ibe37f74a4dcbf68dd6bfd1963530aec907e67534
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/167549
Reviewed-by: Randall Spangler <rspangler@chromium.org>

4 files changed, 32 insertions, 2 deletions

diff --git a/common/lightbar.c b/common/lightbar.c
index 7471e523d7..e90cc06497 100644
--- a/common/lightbar.c
+++ b/common/lightbar.c
@@ -21,6 +21,13 @@
 #include "timer.h"
 #include "util.h"
 
+
+/* The Link lightbar had no specific version. Any new ones should, especially
+ * if they are different in any way. If anything changes, update these.
+ */
+#define LIGHTBAR_IMPLEMENTATION_VERSION 1
+#define LIGHTBAR_IMPLEMENTATION_FLAGS   0x00000000
+
 /* Console output macros */
 #define CPUTS(outstr) cputs(CC_LIGHTBAR, outstr)
 #define CPRINTF(format, args...) cprintf(CC_LIGHTBAR, format, ## args)
@@ -1144,6 +1151,12 @@ static int lpc_cmd_lightbar(struct host_cmd_handler_args *args)
 		CPRINTF("[%T LB_set_params]\n");
 		memcpy(&st.p, &in->set_params, sizeof(st.p));
 		break;
+	case LIGHTBAR_CMD_VERSION:
+		CPRINTF("[%T LB_version]\n");
+		out->version.num = LIGHTBAR_IMPLEMENTATION_VERSION;
+		out->version.flags = LIGHTBAR_IMPLEMENTATION_FLAGS;
+		args->response_size = sizeof(out->version);
+		break;
 	default:
 		CPRINTF("[%T LB bad cmd 0x%x]\n", in->cmd);
 		return EC_RES_INVALID_PARAM;
diff --git a/include/ec_commands.h b/include/ec_commands.h
index 08fb20a996..b3feff7ce1 100644
--- a/include/ec_commands.h
+++ b/include/ec_commands.h
@@ -926,7 +926,7 @@ struct ec_params_lightbar {
 	union {
 		struct {
 			/* no args */
-		} dump, off, on, init, get_seq, get_params;
+		} dump, off, on, init, get_seq, get_params, version;
 
 		struct num {
 			uint8_t num;
@@ -960,6 +960,11 @@ struct ec_response_lightbar {
 
 		struct lightbar_params get_params;
 
+		struct version {
+			uint32_t num;
+			uint32_t flags;
+		} version;
+
 		struct {
 			/* no return params */
 		} off, on, init, brightness, seq, reg, rgb, demo, set_params;
@@ -980,6 +985,7 @@ enum lightbar_command {
 	LIGHTBAR_CMD_DEMO = 9,
 	LIGHTBAR_CMD_GET_PARAMS = 10,
 	LIGHTBAR_CMD_SET_PARAMS = 11,
+	LIGHTBAR_CMD_VERSION = 12,
 	LIGHTBAR_NUM_CMDS
 };
 
diff --git a/util/ectool.c b/util/ectool.c
index b25edb88b8..59ebde3e9a 100644
--- a/util/ectool.c
+++ b/util/ectool.c
@@ -1260,6 +1260,7 @@ static const struct {
 	LB_SIZES(demo),
 	LB_SIZES(get_params),
 	LB_SIZES(set_params),
+	LB_SIZES(version),
 };
 #undef LB_SIZES
 
@@ -1532,6 +1533,15 @@ static int cmd_lightbar(int argc, char **argv)
 		return r;
 	}
 
+	if (!strcasecmp(argv[1], "version")) {
+		r = lb_do_cmd(LIGHTBAR_CMD_VERSION, &param, &resp);
+		if (!r) {
+			printf("num:   %d\n", resp.version.num);
+			printf("flags: 0x%x\n", resp.version.flags);
+		}
+		return r;
+	}
+
 	if (argc == 3 && !strcasecmp(argv[1], "brightness")) {
 		char *e;
 		param.brightness.num = 0xff & strtoul(argv[2], &e, 16);
diff --git a/util/lbplay.c b/util/lbplay.c
index 9cb853aa75..da093a1807 100644
--- a/util/lbplay.c
+++ b/util/lbplay.c
@@ -34,7 +34,8 @@ static const struct {
 	LB_SIZES(get_seq),
 	LB_SIZES(demo),
 	LB_SIZES(get_params),
-	LB_SIZES(set_params)
+	LB_SIZES(set_params),
+	LB_SIZES(version)
 };
 #undef LB_SIZES