[ARM] pxafb: allow insertion of delay to the smart panel command sequence

Some smart panel requires a delay between command sequences, while PXA
LCD controller didn't provide such one, let's emulate this by software.

A software delay marker can be inserted into the command sequence, once
pxafb_smart_queue() detects this, it flushes the previous commands and
delay for a specified number of milliseconds.
Signed-off-by: Eric Miao <eric.miao@marvell.com>

arch/arm/mach-pxa/include/mach/regs-lcd.h

@@ -177,4 +177,11 @@
 
 #define SMART_CMD(x)	(SMART_CMD_WRITE_COMMAND | ((x) & 0xff))
 #define SMART_DAT(x)	(SMART_CMD_WRITE_DATA | ((x) & 0xff))
+
+/* SMART_DELAY() is introduced for software controlled delay primitive which
+ * can be inserted between command sequences, unused command 0x6 is used here
+ * and delay ranges from 0ms ~ 255ms
+ */
+#define SMART_CMD_DELAY		(0x6 << 9)
+#define SMART_DELAY(ms)		(SMART_CMD_DELAY | ((ms) & 0xff))
 #endif /* __ASM_ARCH_REGS_LCD_H */

drivers/video/pxafb.c

@@ -723,12 +723,19 @@ int pxafb_smart_queue(struct fb_info *info, uint16_t *cmds, int n_cmds)
 	int i;
 	struct pxafb_info *fbi = container_of(info, struct pxafb_info, fb);
 
-	/* leave 2 commands for INTERRUPT and WAIT_FOR_SYNC */
-	for (i = 0; i < n_cmds; i++) {
+	for (i = 0; i < n_cmds; i++, cmds++) {
+		/* if it is a software delay, flush and delay */
+		if ((*cmds & 0xff00) == SMART_CMD_DELAY) {
+			pxafb_smart_flush(info);
+			mdelay(*cmds & 0xff);
+			continue;
+		}
+
+		/* leave 2 commands for INTERRUPT and WAIT_FOR_SYNC */
 		if (fbi->n_smart_cmds == CMD_BUFF_SIZE - 8)
 			pxafb_smart_flush(info);
 
-		fbi->smart_cmds[fbi->n_smart_cmds++] = *cmds++;
+		fbi->smart_cmds[fbi->n_smart_cmds++] = *cmds;
 	}
 
 	return 0;