V4L/DVB (9599): cx18: Fix unitialized variable problem upon APU firmware file read failure

If APU firmware file read failed, the jump vector to the APU was undefined and
the APU would be started executing garbage.  Fix uninitialized variable to be
an infinite loop for the APU, but also bail out before even starting the APU.
Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/cx18/cx18-firmware.c

@@ -153,7 +153,7 @@ static int load_apu_fw_direct(const char *fn, u8 __iomem *dst, struct cx18 *cx,
 		return -ENOMEM;
 	}
 
-	*entry_addr = 0xffffffff;
+	*entry_addr = 0;
 	src = (const u32 *)fw->data;
 	vers = fw->data + sizeof(seghdr);
 	sz = fw->size;
@@ -170,7 +170,7 @@ static int load_apu_fw_direct(const char *fn, u8 __iomem *dst, struct cx18 *cx,
 		}
 		CX18_DEBUG_INFO("load segment %x-%x\n", seghdr.addr,
 				seghdr.addr + seghdr.size - 1);
-		if (*entry_addr == 0xffffffff)
+		if (*entry_addr == 0)
 			*entry_addr = seghdr.addr;
 		if (offset + seghdr.size > sz)
 			break;
@@ -340,10 +340,13 @@ int cx18_firmware_init(struct cx18 *cx)
 
 	/* Only if the processor is not running */
 	if (cx18_read_reg(cx, CX18_PROC_SOFT_RESET) & 8) {
-		u32 fw_entry_addr;
+		u32 fw_entry_addr = 0;
 		int sz = load_apu_fw_direct("v4l-cx23418-apu.fw",
 			       cx->enc_mem, cx, &fw_entry_addr);
 
+		if (sz <= 0)
+			return sz;
+
 		/* Clear bit0 for APU to start from 0 */
 		cx18_write_reg(cx, cx18_read_reg(cx, 0xc72030) & ~1, 0xc72030);