[PATCH 1/7] macintosh: Use common code to access RTC

[Finn Thain <fthain@telegraphics.com.au>]

Now that the 68k Mac port has adopted the via-pmu driver, the same RTC
code can be shared between m68k and powerpc. Replace duplicated code in
arch/powerpc and arch/m68k with common RTC accessors for Cuda and PMU.

Drop the problematic WARN_ON which was introduced in commit 22db552b50fa
("powerpc/powermac: Fix rtc read/write functions").

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Arnd Bergmann <arnd@arndb.de>
---
This patch has been regression tested on the following Mac models.
  Centris 660av       (m68k, Cuda)
  PowerBook 190       (m68k, PMU)
  Beige G3 PowerMac   (powerpc, Cuda)
  Pismo G3 PowerBook  (powerpc, PMU)
  G5 PowerMac         (powerpc64, PMU)

These changes were previously submitted as "[RFC] macintosh: Use common
code to access RTC", and prior to that as "[PATCH v3 10/12] macintosh:
Use common code to access RTC", etc.

Changes since RFC:
- pmac_get_rtc_time() is no longer defined terms of pmac_get_boot_time().
- The 64-bit temporary variables were replaced with 64-bit casts,
  consistent with via_read_time() and via_set_rtc_time().
- Rebased.

Changes since v3:
- Rearranged some #ifdefs in arch/powerpc/platforms/powermac/time.c so
  that pmac_set_rtc_time() will return -ENODEV when appropriate.
- Rebased.
---
 arch/m68k/mac/misc.c                   |  75 +++-----------------
 arch/powerpc/platforms/powermac/time.c | 126 ++++++---------------------------
 drivers/macintosh/via-cuda.c           |  35 +++++++++
 drivers/macintosh/via-pmu.c            |  33 +++++++++
 include/linux/cuda.h                   |   4 ++
 include/linux/pmu.h                    |   4 ++
 6 files changed, 106 insertions(+), 171 deletions(-)

diff --git a/arch/m68k/mac/misc.c b/arch/m68k/mac/misc.c
index 1b083c500b9a..ebb3b6d169ea 100644
--- a/arch/m68k/mac/misc.c
+++ b/arch/m68k/mac/misc.c
@@ -37,35 +37,6 @@
 static void (*rom_reset)(void);
 
 #ifdef CONFIG_ADB_CUDA
-static time64_t cuda_read_time(void)
-{
-	struct adb_request req;
-	time64_t time;
-
-	if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_GET_TIME) < 0)
-		return 0;
-	while (!req.complete)
-		cuda_poll();
-
-	time = (u32)((req.reply[3] << 24) | (req.reply[4] << 16) |
-		     (req.reply[5] << 8) | req.reply[6]);
-
-	return time - RTC_OFFSET;
-}
-
-static void cuda_write_time(time64_t time)
-{
-	struct adb_request req;
-	u32 data = lower_32_bits(time + RTC_OFFSET);
-
-	if (cuda_request(&req, NULL, 6, CUDA_PACKET, CUDA_SET_TIME,
-			 (data >> 24) & 0xFF, (data >> 16) & 0xFF,
-			 (data >> 8) & 0xFF, data & 0xFF) < 0)
-		return;
-	while (!req.complete)
-		cuda_poll();
-}
-
 static __u8 cuda_read_pram(int offset)
 {
 	struct adb_request req;
@@ -91,33 +62,6 @@ static void cuda_write_pram(int offset, __u8 data)
 #endif /* CONFIG_ADB_CUDA */
 
 #ifdef CONFIG_ADB_PMU
-static time64_t pmu_read_time(void)
-{
-	struct adb_request req;
-	time64_t time;
-
-	if (pmu_request(&req, NULL, 1, PMU_READ_RTC) < 0)
-		return 0;
-	pmu_wait_complete(&req);
-
-	time = (u32)((req.reply[0] << 24) | (req.reply[1] << 16) |
-		     (req.reply[2] << 8) | req.reply[3]);
-
-	return time - RTC_OFFSET;
-}
-
-static void pmu_write_time(time64_t time)
-{
-	struct adb_request req;
-	u32 data = lower_32_bits(time + RTC_OFFSET);
-
-	if (pmu_request(&req, NULL, 5, PMU_SET_RTC,
-			(data >> 24) & 0xFF, (data >> 16) & 0xFF,
-			(data >> 8) & 0xFF, data & 0xFF) < 0)
-		return;
-	pmu_wait_complete(&req);
-}
-
 static __u8 pmu_read_pram(int offset)
 {
 	struct adb_request req;
@@ -295,13 +239,17 @@ static time64_t via_read_time(void)
  * is basically any machine with Mac II-style ADB.
  */
 
-static void via_write_time(time64_t time)
+static void via_set_rtc_time(struct rtc_time *tm)
 {
 	union {
 		__u8 cdata[4];
 		__u32 idata;
 	} data;
 	__u8 temp;
+	time64_t time;
+
+	time = mktime64(tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,
+	                tm->tm_hour, tm->tm_min, tm->tm_sec);
 
 	/* Clear the write protect bit */
 
@@ -641,12 +589,12 @@ int mac_hwclk(int op, struct rtc_time *t)
 #ifdef CONFIG_ADB_CUDA
 		case MAC_ADB_EGRET:
 		case MAC_ADB_CUDA:
-			now = cuda_read_time();
+			now = cuda_get_time();
 			break;
 #endif
 #ifdef CONFIG_ADB_PMU
 		case MAC_ADB_PB2:
-			now = pmu_read_time();
+			now = pmu_get_time();
 			break;
 #endif
 		default:
@@ -665,24 +613,21 @@ int mac_hwclk(int op, struct rtc_time *t)
 		         __func__, t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
 		         t->tm_hour, t->tm_min, t->tm_sec);
 
-		now = mktime64(t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
-			       t->tm_hour, t->tm_min, t->tm_sec);
-
 		switch (macintosh_config->adb_type) {
 		case MAC_ADB_IOP:
 		case MAC_ADB_II:
 		case MAC_ADB_PB1:
-			via_write_time(now);
+			via_set_rtc_time(t);
 			break;
 #ifdef CONFIG_ADB_CUDA
 		case MAC_ADB_EGRET:
 		case MAC_ADB_CUDA:
-			cuda_write_time(now);
+			cuda_set_rtc_time(t);
 			break;
 #endif
 #ifdef CONFIG_ADB_PMU
 		case MAC_ADB_PB2:
-			pmu_write_time(now);
+			pmu_set_rtc_time(t);
 			break;
 #endif
 		default:
diff --git a/arch/powerpc/platforms/powermac/time.c b/arch/powerpc/platforms/powermac/time.c
index f92c1918fb56..f157e3d071f2 100644
--- a/arch/powerpc/platforms/powermac/time.c
+++ b/arch/powerpc/platforms/powermac/time.c
@@ -44,13 +44,6 @@
 #define DBG(x...)
 #endif
 
-/*
- * Offset between Unix time (1970-based) and Mac time (1904-based). Cuda and PMU
- * times wrap in 2040. If we need to handle later times, the read_time functions
- * need to be changed to interpret wrapped times as post-2040.
- */
-#define RTC_OFFSET	2082844800
-
 /*
  * Calibrate the decrementer frequency with the VIA timer 1.
  */
@@ -90,98 +83,6 @@ long __init pmac_time_init(void)
 	return delta;
 }
 
-#ifdef CONFIG_ADB_CUDA
-static time64_t cuda_get_time(void)
-{
-	struct adb_request req;
-	time64_t now;
-
-	if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_GET_TIME) < 0)
-		return 0;
-	while (!req.complete)
-		cuda_poll();
-	if (req.reply_len != 7)
-		printk(KERN_ERR "cuda_get_time: got %d byte reply\n",
-		       req.reply_len);
-	now = (u32)((req.reply[3] << 24) + (req.reply[4] << 16) +
-		    (req.reply[5] << 8) + req.reply[6]);
-	/* it's either after year 2040, or the RTC has gone backwards */
-	WARN_ON(now < RTC_OFFSET);
-
-	return now - RTC_OFFSET;
-}
-
-#define cuda_get_rtc_time(tm)	rtc_time64_to_tm(cuda_get_time(), (tm))
-
-static int cuda_set_rtc_time(struct rtc_time *tm)
-{
-	u32 nowtime;
-	struct adb_request req;
-
-	nowtime = lower_32_bits(rtc_tm_to_time64(tm) + RTC_OFFSET);
-	if (cuda_request(&req, NULL, 6, CUDA_PACKET, CUDA_SET_TIME,
-			 nowtime >> 24, nowtime >> 16, nowtime >> 8,
-			 nowtime) < 0)
-		return -ENXIO;
-	while (!req.complete)
-		cuda_poll();
-	if ((req.reply_len != 3) && (req.reply_len != 7))
-		printk(KERN_ERR "cuda_set_rtc_time: got %d byte reply\n",
-		       req.reply_len);
-	return 0;
-}
-
-#else
-#define cuda_get_time()		0
-#define cuda_get_rtc_time(tm)
-#define cuda_set_rtc_time(tm)	0
-#endif
-
-#ifdef CONFIG_ADB_PMU
-static time64_t pmu_get_time(void)
-{
-	struct adb_request req;
-	time64_t now;
-
-	if (pmu_request(&req, NULL, 1, PMU_READ_RTC) < 0)
-		return 0;
-	pmu_wait_complete(&req);
-	if (req.reply_len != 4)
-		printk(KERN_ERR "pmu_get_time: got %d byte reply from PMU\n",
-		       req.reply_len);
-	now = (u32)((req.reply[0] << 24) + (req.reply[1] << 16)	+
-		    (req.reply[2] << 8) + req.reply[3]);
-
-	/* it's either after year 2040, or the RTC has gone backwards */
-	WARN_ON(now < RTC_OFFSET);
-
-	return now - RTC_OFFSET;
-}
-
-#define pmu_get_rtc_time(tm)	rtc_time64_to_tm(pmu_get_time(), (tm))
-
-static int pmu_set_rtc_time(struct rtc_time *tm)
-{
-	u32 nowtime;
-	struct adb_request req;
-
-	nowtime = lower_32_bits(rtc_tm_to_time64(tm) + RTC_OFFSET);
-	if (pmu_request(&req, NULL, 5, PMU_SET_RTC, nowtime >> 24,
-			nowtime >> 16, nowtime >> 8, nowtime) < 0)
-		return -ENXIO;
-	pmu_wait_complete(&req);
-	if (req.reply_len != 0)
-		printk(KERN_ERR "pmu_set_rtc_time: %d byte reply from PMU\n",
-		       req.reply_len);
-	return 0;
-}
-
-#else
-#define pmu_get_time()		0
-#define pmu_get_rtc_time(tm)
-#define pmu_set_rtc_time(tm)	0
-#endif
-
 #ifdef CONFIG_PMAC_SMU
 static time64_t smu_get_time(void)
 {
@@ -191,11 +92,6 @@ static time64_t smu_get_time(void)
 		return 0;
 	return rtc_tm_to_time64(&tm);
 }
-
-#else
-#define smu_get_time()			0
-#define smu_get_rtc_time(tm, spin)
-#define smu_set_rtc_time(tm, spin)	0
 #endif
 
 /* Can't be __init, it's called when suspending and resuming */
@@ -203,12 +99,18 @@ time64_t pmac_get_boot_time(void)
 {
 	/* Get the time from the RTC, used only at boot time */
 	switch (sys_ctrler) {
+#ifdef CONFIG_ADB_CUDA
 	case SYS_CTRLER_CUDA:
 		return cuda_get_time();
+#endif
+#ifdef CONFIG_ADB_PMU
 	case SYS_CTRLER_PMU:
 		return pmu_get_time();
+#endif
+#ifdef CONFIG_PMAC_SMU
 	case SYS_CTRLER_SMU:
 		return smu_get_time();
+#endif
 	default:
 		return 0;
 	}
@@ -218,15 +120,21 @@ void pmac_get_rtc_time(struct rtc_time *tm)
 {
 	/* Get the time from the RTC, used only at boot time */
 	switch (sys_ctrler) {
+#ifdef CONFIG_ADB_CUDA
 	case SYS_CTRLER_CUDA:
-		cuda_get_rtc_time(tm);
+		rtc_time64_to_tm(cuda_get_time(), tm);
 		break;
+#endif
+#ifdef CONFIG_ADB_PMU
 	case SYS_CTRLER_PMU:
-		pmu_get_rtc_time(tm);
+		rtc_time64_to_tm(pmu_get_time(), tm);
 		break;
+#endif
+#ifdef CONFIG_PMAC_SMU
 	case SYS_CTRLER_SMU:
 		smu_get_rtc_time(tm, 1);
 		break;
+#endif
 	default:
 		;
 	}
@@ -235,12 +143,18 @@ void pmac_get_rtc_time(struct rtc_time *tm)
 int pmac_set_rtc_time(struct rtc_time *tm)
 {
 	switch (sys_ctrler) {
+#ifdef CONFIG_ADB_CUDA
 	case SYS_CTRLER_CUDA:
 		return cuda_set_rtc_time(tm);
+#endif
+#ifdef CONFIG_ADB_PMU
 	case SYS_CTRLER_PMU:
 		return pmu_set_rtc_time(tm);
+#endif
+#ifdef CONFIG_PMAC_SMU
 	case SYS_CTRLER_SMU:
 		return smu_set_rtc_time(tm, 1);
+#endif
 	default:
 		return -ENODEV;
 	}
diff --git a/drivers/macintosh/via-cuda.c b/drivers/macintosh/via-cuda.c
index 98dd702eb867..bbec6ac0a966 100644
--- a/drivers/macintosh/via-cuda.c
+++ b/drivers/macintosh/via-cuda.c
@@ -766,3 +766,38 @@ cuda_input(unsigned char *buf, int nb)
 	               buf, nb, false);
     }
 }
+
+/* Offset between Unix time (1970-based) and Mac time (1904-based) */
+#define RTC_OFFSET	2082844800
+
+time64_t cuda_get_time(void)
+{
+	struct adb_request req;
+	u32 now;
+
+	if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_GET_TIME) < 0)
+		return 0;
+	while (!req.complete)
+		cuda_poll();
+	if (req.reply_len != 7)
+		pr_err("%s: got %d byte reply\n", __func__, req.reply_len);
+	now = (req.reply[3] << 24) + (req.reply[4] << 16) +
+	      (req.reply[5] << 8) + req.reply[6];
+	return (time64_t)now - RTC_OFFSET;
+}
+
+int cuda_set_rtc_time(struct rtc_time *tm)
+{
+	u32 now;
+	struct adb_request req;
+
+	now = lower_32_bits(rtc_tm_to_time64(tm) + RTC_OFFSET);
+	if (cuda_request(&req, NULL, 6, CUDA_PACKET, CUDA_SET_TIME,
+	                 now >> 24, now >> 16, now >> 8, now) < 0)
+		return -ENXIO;
+	while (!req.complete)
+		cuda_poll();
+	if ((req.reply_len != 3) && (req.reply_len != 7))
+		pr_err("%s: got %d byte reply\n", __func__, req.reply_len);
+	return 0;
+}
diff --git a/drivers/macintosh/via-pmu.c b/drivers/macintosh/via-pmu.c
index d72c450aebe5..60f57e2abf21 100644
--- a/drivers/macintosh/via-pmu.c
+++ b/drivers/macintosh/via-pmu.c
@@ -1737,6 +1737,39 @@ pmu_enable_irled(int on)
 	pmu_wait_complete(&req);
 }
 
+/* Offset between Unix time (1970-based) and Mac time (1904-based) */
+#define RTC_OFFSET	2082844800
+
+time64_t pmu_get_time(void)
+{
+	struct adb_request req;
+	u32 now;
+
+	if (pmu_request(&req, NULL, 1, PMU_READ_RTC) < 0)
+		return 0;
+	pmu_wait_complete(&req);
+	if (req.reply_len != 4)
+		pr_err("%s: got %d byte reply\n", __func__, req.reply_len);
+	now = (req.reply[0] << 24) + (req.reply[1] << 16) +
+	      (req.reply[2] << 8) + req.reply[3];
+	return (time64_t)now - RTC_OFFSET;
+}
+
+int pmu_set_rtc_time(struct rtc_time *tm)
+{
+	u32 now;
+	struct adb_request req;
+
+	now = lower_32_bits(rtc_tm_to_time64(tm) + RTC_OFFSET);
+	if (pmu_request(&req, NULL, 5, PMU_SET_RTC,
+	                now >> 24, now >> 16, now >> 8, now) < 0)
+		return -ENXIO;
+	pmu_wait_complete(&req);
+	if (req.reply_len != 0)
+		pr_err("%s: got %d byte reply\n", __func__, req.reply_len);
+	return 0;
+}
+
 void
 pmu_restart(void)
 {
diff --git a/include/linux/cuda.h b/include/linux/cuda.h
index 056867f09a01..45bfe9d61271 100644
--- a/include/linux/cuda.h
+++ b/include/linux/cuda.h
@@ -8,6 +8,7 @@
 #ifndef _LINUX_CUDA_H
 #define _LINUX_CUDA_H
 
+#include <linux/rtc.h>
 #include <uapi/linux/cuda.h>
 
 
@@ -16,4 +17,7 @@ extern int cuda_request(struct adb_request *req,
 			void (*done)(struct adb_request *), int nbytes, ...);
 extern void cuda_poll(void);
 
+extern time64_t cuda_get_time(void);
+extern int cuda_set_rtc_time(struct rtc_time *tm);
+
 #endif /* _LINUX_CUDA_H */
diff --git a/include/linux/pmu.h b/include/linux/pmu.h
index 9ac8fc60ad49..52453a24a24f 100644
--- a/include/linux/pmu.h
+++ b/include/linux/pmu.h
@@ -9,6 +9,7 @@
 #ifndef _LINUX_PMU_H
 #define _LINUX_PMU_H
 
+#include <linux/rtc.h>
 #include <uapi/linux/pmu.h>
 
 
@@ -36,6 +37,9 @@ static inline void pmu_resume(void)
 
 extern void pmu_enable_irled(int on);
 
+extern time64_t pmu_get_time(void);
+extern int pmu_set_rtc_time(struct rtc_time *tm);
+
 extern void pmu_restart(void);
 extern void pmu_shutdown(void);
 extern void pmu_unlock(void);
-- 
2.16.4