@@ -5,6 +5,7 @@
#include <linux/delay.h>
#include <linux/device.h>
+#include <linux/limits.h>
#include <linux/module.h>
#include <linux/platform_data/cros_ec_commands.h>
#include <linux/platform_data/cros_ec_proto.h>
@@ -1069,3 +1070,37 @@ int cros_ec_cmd_readmem(struct cros_ec_device *ec_dev, u8 offset, u8 size, void
¶ms, sizeof(params), dest, size);
}
EXPORT_SYMBOL_GPL(cros_ec_cmd_readmem);
+
+/**
+ * cros_ec_get_cmd_versions - Get supported version mask.
+ *
+ * @ec_dev: EC device
+ * @cmd: Command to test
+ *
+ * Return: version mask on success, negative error number on failure.
+ */
+int cros_ec_get_cmd_versions(struct cros_ec_device *ec_dev, u16 cmd)
+{
+ struct ec_params_get_cmd_versions req_v0;
+ struct ec_params_get_cmd_versions_v1 req_v1;
+ struct ec_response_get_cmd_versions resp;
+ int ret;
+
+ if (cmd <= U8_MAX) {
+ req_v0.cmd = cmd;
+ ret = cros_ec_cmd(ec_dev, 0, EC_CMD_GET_CMD_VERSIONS,
+ &req_v0, sizeof(req_v0), &resp, sizeof(resp));
+ } else {
+ req_v1.cmd = cmd;
+ ret = cros_ec_cmd(ec_dev, 1, EC_CMD_GET_CMD_VERSIONS,
+ &req_v1, sizeof(req_v1), &resp, sizeof(resp));
+ }
+
+ if (ret == -EINVAL)
+ return 0; /* Command not implemented */
+ else if (ret < 0)
+ return ret;
+ else
+ return resp.version_mask;
+}
+EXPORT_SYMBOL_GPL(cros_ec_get_cmd_versions);
@@ -263,6 +263,8 @@ int cros_ec_cmd(struct cros_ec_device *ec_dev, unsigned int version, int command
int cros_ec_cmd_readmem(struct cros_ec_device *ec_dev, u8 offset, u8 size, void *dest);
+int cros_ec_get_cmd_versions(struct cros_ec_device *ec_dev, u16 cmd);
+
/**
* cros_ec_get_time_ns() - Return time in ns.
*
Retrieving the supported versions of a command is a fairly common operation. Provide a helper for it. If the command is not supported at all the EC returns -EINVAL/EC_RES_INVALID_PARAMS. This error is translated into an empty version mask as that is easier to handle for callers and they don't need to know about the error details. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> --- drivers/platform/chrome/cros_ec_proto.c | 35 +++++++++++++++++++++++++++++ include/linux/platform_data/cros_ec_proto.h | 2 ++ 2 files changed, 37 insertions(+)