drivers/char/rtc.c: Handle memory-mapped chips properly

@@ -35,23 +35,22 @@
  *	1.09a	Pete Zaitcev: Sun SPARC
  *	1.09b	Jeff Garzik: Modularize, init cleanup
  *	1.09c	Jeff Garzik: SMP cleanup
- *	1.10    Paul Barton-Davis: add support for async I/O
+ *	1.10	Paul Barton-Davis: add support for async I/O
  *	1.10a	Andrea Arcangeli: Alpha updates
  *	1.10b	Andrew Morton: SMP lock fix
  *	1.10c	Cesar Barros: SMP locking fixes and cleanup
  *	1.10d	Paul Gortmaker: delete paranoia check in rtc_exit
  *	1.10e	Maciej W. Rozycki: Handle DECstation's year weirdness.
- *      1.11    Takashi Iwai: Kernel access functions
+ *	1.11	Takashi Iwai: Kernel access functions
  *			      rtc_register/rtc_unregister/rtc_control
  *      1.11a   Daniele Bellucci: Audit create_proc_read_entry in rtc_init
- *	1.12	Venkatesh Pallipadi: Hooks for emulating rtc on HPET base-timer
+ *	1.12    Venkatesh Pallipadi: Hooks for emulating rtc on HPET base-timer
  *		CONFIG_HPET_EMULATE_RTC
+ *	1.12a	Maciej W. Rozycki: Handle memory-mapped chips properly.
  *	1.12ac	Alan Cox: Allow read access to the day of week register
  */
 
-#define RTC_VERSION		"1.12ac"
-
-#define RTC_IO_EXTENT	0x8
+#define RTC_VERSION		"1.12a"
 
 /*
  *	Note that *all* calls to CMOS_READ and CMOS_WRITE are done with

@@ -338,7 +337,15 @@
 	if (rtc_has_irq == 0)
 		return -EIO;
 
-	if (count < sizeof(unsigned))
+	/*
+	 * Historically this function used to assume that sizeof(unsigned long)
+	 * is the same in userspace and kernelspace.  This lead to problems
+	 * for configurations with multiple ABIs such a the MIPS o32 and 64
+	 * ABIs supported on the same kernel.  So now we support read of both
+	 * 4 and 8 bytes and assume that's the sizeof(unsigned long) in the
+	 * userspace ABI.
+	 */
+	if (count != sizeof(unsigned int) && count !=  sizeof(unsigned long))
 		return -EINVAL;
 
 	add_wait_queue(&rtc_wait, &wait);

@@ -369,10 +376,12 @@
 		schedule();
 	} while (1);
 
-	if (count < sizeof(unsigned long))
-		retval = put_user(data, (unsigned int __user *)buf) ?: sizeof(int); 
+	if (count == sizeof(unsigned int))
+		retval = put_user(data, (unsigned int __user *)buf) ?: sizeof(int);
 	else
 		retval = put_user(data, (unsigned long __user *)buf) ?: sizeof(long);
+	if (!retval)
+		retval = count;
  out:
 	current->state = TASK_RUNNING;
 	remove_wait_queue(&rtc_wait, &wait);

@@ -924,6 +933,9 @@
 	struct sparc_isa_device *isa_dev;
 #endif
 #endif
+#ifndef __sparc__
+	void *r;
+#endif
 
 #ifdef __sparc__
 	for_each_ebus(ebus) {

@@ -969,8 +981,13 @@
 	}
 no_irq:
 #else
-	if (!request_region(RTC_PORT(0), RTC_IO_EXTENT, "rtc")) {
-		printk(KERN_ERR "rtc: I/O port %d is not free.\n", RTC_PORT (0));
+	if (RTC_IOMAPPED)
+		r = request_region(RTC_PORT(0), RTC_IO_EXTENT, "rtc");
+	else
+		r = request_mem_region(RTC_PORT(0), RTC_IO_EXTENT, "rtc");
+	if (!r) {
+		printk(KERN_ERR "rtc: I/O resource %lx is not free.\n",
+		       (long)(RTC_PORT(0)));
 		return -EIO;
 	}
 

@@ -984,7 +1001,10 @@
 	if(request_irq(RTC_IRQ, rtc_int_handler_ptr, SA_INTERRUPT, "rtc", NULL)) {
 		/* Yeah right, seeing as irq 8 doesn't even hit the bus. */
 		printk(KERN_ERR "rtc: IRQ %d is not free.\n", RTC_IRQ);
-		release_region(RTC_PORT(0), RTC_IO_EXTENT);
+		if (RTC_IOMAPPED)
+			release_region(RTC_PORT(0), RTC_IO_EXTENT);
+		else
+			release_mem_region(RTC_PORT(0), RTC_IO_EXTENT);
 		return -EIO;
 	}
 	hpet_rtc_timer_init();

@@ -1084,7 +1104,10 @@
 	if (rtc_has_irq)
 		free_irq (rtc_irq, &rtc_port);
 #else
-	release_region (RTC_PORT (0), RTC_IO_EXTENT);
+	if (RTC_IOMAPPED)
+		release_region(RTC_PORT(0), RTC_IO_EXTENT);
+	else
+		release_mem_region(RTC_PORT(0), RTC_IO_EXTENT);
 #ifdef RTC_IRQ
 	if (rtc_has_irq)
 		free_irq (RTC_IRQ, NULL);