greybus: firmware: Add 'status' byte to backend fw version response

The backend processor may not be ready to return the version of firmware
it is running by the time AP requests for it. The greybus specification
is updated to return 1-byte 'status' to return the error type, RETRY is
one of them.

This patch implements that in greybus now.

Note that the version structure was common across interface and backend
version requests earlier, but that is changing as well.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/fw-management.c

@@ -103,7 +103,7 @@ unlock:
 }
 
 static int fw_mgmt_interface_fw_version_operation(struct fw_mgmt *fw_mgmt,
-		struct fw_mgmt_ioc_get_fw *fw_info)
+		struct fw_mgmt_ioc_get_intf_version *fw_info)
 {
 	struct gb_connection *connection = fw_mgmt->connection;
 	struct gb_fw_mgmt_interface_fw_version_response response;
@@ -241,7 +241,7 @@ static int fw_mgmt_interface_fw_loaded_operation(struct gb_operation *op)
 }
 
 static int fw_mgmt_backend_fw_version_operation(struct fw_mgmt *fw_mgmt,
-		struct fw_mgmt_ioc_get_fw *fw_info)
+		struct fw_mgmt_ioc_get_backend_version *fw_info)
 {
 	struct gb_connection *connection = fw_mgmt->connection;
 	struct gb_fw_mgmt_backend_fw_version_request request;
@@ -269,8 +269,29 @@ static int fw_mgmt_backend_fw_version_operation(struct fw_mgmt *fw_mgmt,
 		return ret;
 	}
 
-	fw_info->major = le16_to_cpu(response.major);
-	fw_info->minor = le16_to_cpu(response.minor);
+	fw_info->status = response.status;
+
+	/* Reset version as that should be non-zero only for success case */
+	fw_info->major = 0;
+	fw_info->minor = 0;
+
+	switch (fw_info->status) {
+	case GB_FW_BACKEND_VERSION_STATUS_SUCCESS:
+		fw_info->major = le16_to_cpu(response.major);
+		fw_info->minor = le16_to_cpu(response.minor);
+		break;
+	case GB_FW_BACKEND_VERSION_STATUS_NOT_AVAILABLE:
+	case GB_FW_BACKEND_VERSION_STATUS_RETRY:
+		break;
+	case GB_FW_BACKEND_VERSION_STATUS_NOT_SUPPORTED:
+		dev_err(fw_mgmt->parent,
+			"Firmware with tag %s is not supported by Interface\n",
+			fw_info->firmware_tag);
+		break;
+	default:
+		dev_err(fw_mgmt->parent, "Invalid status received: %u\n",
+			fw_info->status);
+	}
 
 	return 0;
 }
@@ -387,7 +408,8 @@ static int fw_mgmt_release(struct inode *inode, struct file *file)
 static int fw_mgmt_ioctl(struct fw_mgmt *fw_mgmt, unsigned int cmd,
 			 void __user *buf)
 {
-	struct fw_mgmt_ioc_get_fw fw_info;
+	struct fw_mgmt_ioc_get_intf_version intf_fw_info;
+	struct fw_mgmt_ioc_get_backend_version backend_fw_info;
 	struct fw_mgmt_ioc_intf_load_and_validate intf_load;
 	struct fw_mgmt_ioc_backend_fw_update backend_update;
 	unsigned int timeout;
@@ -399,23 +421,27 @@ static int fw_mgmt_ioctl(struct fw_mgmt *fw_mgmt, unsigned int cmd,
 
 	switch (cmd) {
 	case FW_MGMT_IOC_GET_INTF_FW:
-		ret = fw_mgmt_interface_fw_version_operation(fw_mgmt, &fw_info);
+		ret = fw_mgmt_interface_fw_version_operation(fw_mgmt,
+							     &intf_fw_info);
 		if (ret)
 			return ret;
 
-		if (copy_to_user(buf, &fw_info, sizeof(fw_info)))
+		if (copy_to_user(buf, &intf_fw_info, sizeof(intf_fw_info)))
 			return -EFAULT;
 
 		return 0;
 	case FW_MGMT_IOC_GET_BACKEND_FW:
-		if (copy_from_user(&fw_info, buf, sizeof(fw_info)))
+		if (copy_from_user(&backend_fw_info, buf,
+				   sizeof(backend_fw_info)))
 			return -EFAULT;
 
-		ret = fw_mgmt_backend_fw_version_operation(fw_mgmt, &fw_info);
+		ret = fw_mgmt_backend_fw_version_operation(fw_mgmt,
+							   &backend_fw_info);
 		if (ret)
 			return ret;
 
-		if (copy_to_user(buf, &fw_info, sizeof(fw_info)))
+		if (copy_to_user(buf, &backend_fw_info,
+				 sizeof(backend_fw_info)))
 			return -EFAULT;
 
 		return 0;

drivers/staging/greybus/greybus_firmware.h

@@ -72,14 +72,29 @@
 #define GB_FW_U_BACKEND_FW_STATUS_FAIL_FETCH	0x03
 #define GB_FW_U_BACKEND_FW_STATUS_FAIL_WRITE	0x04
 #define GB_FW_U_BACKEND_FW_STATUS_INT		0x05
+#define GB_FW_U_BACKEND_FW_STATUS_RETRY		0x06
+#define GB_FW_U_BACKEND_FW_STATUS_NOT_SUPPORTED	0x07
+
+#define GB_FW_U_BACKEND_VERSION_STATUS_SUCCESS		0x01
+#define GB_FW_U_BACKEND_VERSION_STATUS_NOT_AVAILABLE	0x02
+#define GB_FW_U_BACKEND_VERSION_STATUS_NOT_SUPPORTED	0x03
+#define GB_FW_U_BACKEND_VERSION_STATUS_RETRY		0x04
+#define GB_FW_U_BACKEND_VERSION_STATUS_FAIL_INT		0x05
 
 /* IOCTL support */
-struct fw_mgmt_ioc_get_fw {
+struct fw_mgmt_ioc_get_intf_version {
 	__u8 firmware_tag[GB_FIRMWARE_U_TAG_MAX_LEN];
 	__u16 major;
 	__u16 minor;
 } __attribute__ ((__packed__));
 
+struct fw_mgmt_ioc_get_backend_version {
+	__u8 firmware_tag[GB_FIRMWARE_U_TAG_MAX_LEN];
+	__u16 major;
+	__u16 minor;
+	__u8 status;
+} __attribute__ ((__packed__));
+
 struct fw_mgmt_ioc_intf_load_and_validate {
 	__u8 firmware_tag[GB_FIRMWARE_U_TAG_MAX_LEN];
 	__u8 load_method;
@@ -94,8 +109,8 @@ struct fw_mgmt_ioc_backend_fw_update {
 } __attribute__ ((__packed__));
 
 #define FW_MGMT_IOCTL_BASE			'F'
-#define FW_MGMT_IOC_GET_INTF_FW			_IOR(FW_MGMT_IOCTL_BASE, 0, struct fw_mgmt_ioc_get_fw)
-#define FW_MGMT_IOC_GET_BACKEND_FW		_IOWR(FW_MGMT_IOCTL_BASE, 1, struct fw_mgmt_ioc_get_fw)
+#define FW_MGMT_IOC_GET_INTF_FW			_IOR(FW_MGMT_IOCTL_BASE, 0, struct fw_mgmt_ioc_get_intf_version)
+#define FW_MGMT_IOC_GET_BACKEND_FW		_IOWR(FW_MGMT_IOCTL_BASE, 1, struct fw_mgmt_ioc_get_backend_version)
 #define FW_MGMT_IOC_INTF_LOAD_AND_VALIDATE	_IOWR(FW_MGMT_IOCTL_BASE, 2, struct fw_mgmt_ioc_intf_load_and_validate)
 #define FW_MGMT_IOC_INTF_BACKEND_FW_UPDATE	_IOWR(FW_MGMT_IOCTL_BASE, 3, struct fw_mgmt_ioc_backend_fw_update)
 #define FW_MGMT_IOC_SET_TIMEOUT_MS		_IOW(FW_MGMT_IOCTL_BASE, 4, unsigned int)

drivers/staging/greybus/greybus_protocols.h

@@ -370,6 +370,12 @@ struct gb_fw_download_release_firmware_request {
 #define GB_FW_BACKEND_FW_STATUS_RETRY		0x06
 #define GB_FW_BACKEND_FW_STATUS_NOT_SUPPORTED	0x07
 
+#define GB_FW_BACKEND_VERSION_STATUS_SUCCESS		0x01
+#define GB_FW_BACKEND_VERSION_STATUS_NOT_AVAILABLE	0x02
+#define GB_FW_BACKEND_VERSION_STATUS_NOT_SUPPORTED	0x03
+#define GB_FW_BACKEND_VERSION_STATUS_RETRY		0x04
+#define GB_FW_BACKEND_VERSION_STATUS_FAIL_INT		0x05
+
 /* firmware management interface firmware version request has no payload */
 struct gb_fw_mgmt_interface_fw_version_response {
 	__u8			firmware_tag[GB_FIRMWARE_TAG_MAX_LEN];
@@ -402,6 +408,7 @@ struct gb_fw_mgmt_backend_fw_version_request {
 struct gb_fw_mgmt_backend_fw_version_response {
 	__le16			major;
 	__le16			minor;
+	__u8			status;
 } __packed;
 
 /* firmware management backend firmware update request */