[media] s5p-mfc: Support multiple firmware sub-versions

For MFC firmwares, improved versions with bug fixes and
feature additions are released keeping the firmware version
including major and minor number same. The issue came with
the release of a new MFCv6 firmware with an interface change.
This patch adds the support of accepting multiple firmware
binaries for every version with the driver trying to load
firmwares starting from latest. This ensures full backward
compatibility regardless of which firmware version and kernel
version is used.

Signed-off-by: Arun Kumar K <arun.kk@samsung.com>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/platform/s5p-mfc/s5p_mfc.c

@@ -1351,7 +1351,7 @@ static struct s5p_mfc_variant mfc_drvdata_v5 = {
 	.port_num	= MFC_NUM_PORTS,
 	.buf_size	= &buf_size_v5,
 	.buf_align	= &mfc_buf_align_v5,
-	.fw_name	= "s5p-mfc.fw",
+	.fw_name[0]	= "s5p-mfc.fw",
 };
 
 struct s5p_mfc_buf_size_v6 mfc_buf_size_v6 = {
@@ -1378,7 +1378,12 @@ static struct s5p_mfc_variant mfc_drvdata_v6 = {
 	.port_num	= MFC_NUM_PORTS_V6,
 	.buf_size	= &buf_size_v6,
 	.buf_align	= &mfc_buf_align_v6,
-	.fw_name        = "s5p-mfc-v6.fw",
+	.fw_name[0]     = "s5p-mfc-v6.fw",
+	/*
+	 * v6-v2 firmware contains bug fixes and interface change
+	 * for init buffer command
+	 */
+	.fw_name[1]     = "s5p-mfc-v6-v2.fw",
 };
 
 struct s5p_mfc_buf_size_v6 mfc_buf_size_v7 = {
@@ -1405,7 +1410,7 @@ static struct s5p_mfc_variant mfc_drvdata_v7 = {
 	.port_num	= MFC_NUM_PORTS_V7,
 	.buf_size	= &buf_size_v7,
 	.buf_align	= &mfc_buf_align_v7,
-	.fw_name        = "s5p-mfc-v7.fw",
+	.fw_name[0]     = "s5p-mfc-v7.fw",
 };
 
 struct s5p_mfc_buf_size_v6 mfc_buf_size_v8 = {
@@ -1432,7 +1437,7 @@ static struct s5p_mfc_variant mfc_drvdata_v8 = {
 	.port_num	= MFC_NUM_PORTS_V8,
 	.buf_size	= &buf_size_v8,
 	.buf_align	= &mfc_buf_align_v8,
-	.fw_name        = "s5p-mfc-v8.fw",
+	.fw_name[0]     = "s5p-mfc-v8.fw",
 };
 
 static struct platform_device_id mfc_driver_ids[] = {

drivers/media/platform/s5p-mfc/s5p_mfc_common.h

@@ -38,6 +38,8 @@
 #define MFC_BANK2_ALIGN_ORDER	13
 #define MFC_BASE_ALIGN_ORDER	17
 
+#define MFC_FW_MAX_VERSIONS	2
+
 #include <media/videobuf2-dma-contig.h>
 
 static inline dma_addr_t s5p_mfc_mem_cookie(void *a, void *b)
@@ -163,6 +165,11 @@ enum s5p_mfc_decode_arg {
 	MFC_DEC_RES_CHANGE,
 };
 
+enum s5p_mfc_fw_ver {
+	MFC_FW_V1,
+	MFC_FW_V2,
+};
+
 #define MFC_BUF_FLAG_USED	(1 << 0)
 #define MFC_BUF_FLAG_EOS	(1 << 1)
 
@@ -225,7 +232,7 @@ struct s5p_mfc_variant {
 	u32 version_bit;
 	struct s5p_mfc_buf_size *buf_size;
 	struct s5p_mfc_buf_align *buf_align;
-	char	*fw_name;
+	char	*fw_name[MFC_FW_MAX_VERSIONS];
 };
 
 /**
@@ -287,6 +294,7 @@ struct s5p_mfc_priv_buf {
  * @warn_start:		hardware error code from which warnings start
  * @mfc_ops:		ops structure holding HW operation function pointers
  * @mfc_cmds:		cmd structure holding HW commands function pointers
+ * @fw_ver:		loaded firmware sub-version
  *
  */
 struct s5p_mfc_dev {
@@ -331,6 +339,7 @@ struct s5p_mfc_dev {
 	struct s5p_mfc_hw_ops *mfc_ops;
 	struct s5p_mfc_hw_cmds *mfc_cmds;
 	const struct s5p_mfc_regs *mfc_regs;
+	enum s5p_mfc_fw_ver fw_ver;
 };
 
 /**

drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c

@@ -77,14 +77,23 @@ int s5p_mfc_alloc_firmware(struct s5p_mfc_dev *dev)
 int s5p_mfc_load_firmware(struct s5p_mfc_dev *dev)
 {
 	struct firmware *fw_blob;
-	int err;
+	int i, err = -EINVAL;
 
 	/* Firmare has to be present as a separate file or compiled
 	 * into kernel. */
 	mfc_debug_enter();
 
-	err = request_firmware((const struct firmware **)&fw_blob,
-				     dev->variant->fw_name, dev->v4l2_dev.dev);
+	for (i = MFC_FW_MAX_VERSIONS - 1; i >= 0; i--) {
+		if (!dev->variant->fw_name[i])
+			continue;
+		err = request_firmware((const struct firmware **)&fw_blob,
+				dev->variant->fw_name[i], dev->v4l2_dev.dev);
+		if (!err) {
+			dev->fw_ver = (enum s5p_mfc_fw_ver) i;
+			break;
+		}
+	}
+
 	if (err != 0) {
 		mfc_err("Firmware is not present in the /lib/firmware directory nor compiled in kernel\n");
 		return -EINVAL;