[PATCH] Corgi Touchscreen: Allow the driver to share the PMU

The Corgi Touchscreen driver uses the PMU as an accurate timing source which
conflicts with its usage for performance monitoring.  This patch allows it to
be shared with other users such as oprofile.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/input/touchscreen/corgi_ts.c

@@ -53,8 +53,8 @@ struct corgi_ts {
 
 #define SyncHS()	while((STATUS_HSYNC) == 0); while((STATUS_HSYNC) != 0);
 #define CCNT(a)		asm volatile ("mrc p14, 0, %0, C1, C0, 0" : "=r"(a))
-#define CCNT_ON()	{int pmnc = 1; asm volatile ("mcr p14, 0, %0, C0, C0, 0" : : "r"(pmnc));}
-#define CCNT_OFF()	{int pmnc = 0; asm volatile ("mcr p14, 0, %0, C0, C0, 0" : : "r"(pmnc));}
+#define PMNC_GET(x)	asm volatile ("mrc p14, 0, %0, C0, C0, 0" : "=r"(x))
+#define PMNC_SET(x)	asm volatile ("mcr p14, 0, %0, C0, C0, 0" : : "r"(x))
 
 #define WAIT_HS_400_VGA		7013U	// 17.615us
 #define WAIT_HS_400_QVGA	16622U	// 41.750us
@@ -96,14 +96,17 @@ static unsigned long calc_waittime(void)
 
 static int sync_receive_data_send_cmd(int doRecive, int doSend, unsigned int address, unsigned long wait_time)
 {
+	unsigned long timer1 = 0, timer2, pmnc = 0;
 	int pos = 0;
-	unsigned long timer1 = 0, timer2;
 	int dosleep;
 
 	dosleep = !w100fb_get_blanking();
 
 	if (dosleep && doSend) {
-		CCNT_ON();
+		PMNC_GET(pmnc);
+		if (!(pmnc & 0x01))
+			PMNC_SET(pmnc | 0x01);
+
 		/* polling HSync */
 		SyncHS();
 		/* get CCNT */
@@ -134,8 +137,8 @@ static int sync_receive_data_send_cmd(int doRecive, int doSend, unsigned int add
 				CCNT(timer2);
 		}
 		corgi_ssp_ads7846_put(cmd);
-		if (dosleep)
-			CCNT_OFF();
+		if (dosleep && !(pmnc & 0x01))
+			PMNC_SET(pmnc);
 	}
 	return pos;
 }