[ARM PATCH] 1934/2: Consolidate code to set CKEN on PXA

Patch from Ian Campbell

I've seen comments several times that various PXA drivers
update CKEN in an unsafe manner. This patch consolidates
this code into a single function pxa_set_cken() and updates
all the in tree drivers to use it.

arch/arm/mach-pxa/generic.c

@@ -58,6 +58,24 @@ void pxa_gpio_mode(int gpio_mode)
 
 EXPORT_SYMBOL(pxa_gpio_mode);
 
+/*
+ * Routine to safely enable or disable a clock in the CKEN
+ */
+void pxa_set_cken(int clock, int enable)
+{
+	unsigned long flags;
+	local_irq_save(flags);
+
+	if (enable)
+		CKEN |= clock;
+	else
+		CKEN &= ~clock;
+
+	local_irq_restore(flags);
+}
+
+EXPORT_SYMBOL(pxa_set_cken);
+
 /*
  * Intel PXA2xx internal register mapping.
  *

drivers/serial/pxa.c

@@ -571,14 +571,9 @@ serial_pxa_pm(struct uart_port *port, unsigned int state,
 	      unsigned int oldstate)
 {
 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
-	if (state) {
-		/* sleep */
-		CKEN &= ~up->cken;
-	} else {
-		/* wake */
-		CKEN |= up->cken;
+	pxa_set_cken(up->cken, !state);
+	if (!state)
 		udelay(1);
-	}
 }
 
 static void serial_pxa_release_port(struct uart_port *port)

drivers/usb/gadget/pxa2xx_udc.c

@@ -1406,7 +1406,7 @@ static void udc_disable(struct pxa2xx_udc *dev)
 
 #ifdef	CONFIG_ARCH_PXA
         /* Disable clock for USB device */
-        CKEN &= ~CKEN11_USB;
+	pxa_set_cken(CKEN11_USB, 0);
 #endif
 
 	ep0_idle (dev);
@@ -1452,7 +1452,7 @@ static void udc_enable (struct pxa2xx_udc *dev)
 
 #ifdef	CONFIG_ARCH_PXA
         /* Enable clock for USB device */
-        CKEN |= CKEN11_USB;
+	pxa_set_cken(CKEN11_USB, 1);
 #endif
 
 	/* try to clear these bits before we enable the udc */

drivers/video/pxafb.c

@@ -1237,7 +1237,6 @@ int __init pxafb_probe(struct device *dev)
 {
 	struct pxafb_info *fbi;
 	struct pxafb_mach_info *inf;
-	unsigned long flags;
 	int ret;
 
 	dev_dbg(dev, "pxafb_probe\n");
@@ -1301,9 +1300,7 @@ int __init pxafb_probe(struct device *dev)
 		goto failed;
 	}
 	/* enable LCD controller clock */
-	local_irq_save(flags);
-	CKEN |= CKEN16_LCD;
-	local_irq_restore(flags);
+	pxa_set_cken(CKEN16_LCD, 1);
 
 	ret = request_irq(IRQ_LCD, pxafb_handle_irq, SA_INTERRUPT, "LCD", fbi);
 	if (ret) {

include/asm-arm/arch-pxa/hardware.h

@@ -82,6 +82,11 @@ typedef struct { volatile u32 offset[4096]; } __regbase;
  */
 extern void pxa_gpio_mode( int gpio_mode );
 
+/*
+ * Routine to enable or disable CKEN
+ */
+extern void pxa_set_cken(int clock, int enable);
+
 /*
  * return current memory and LCD clock frequency in units of 10kHz
  */