[DRIVER][RTC] fix alarm feature on PCF2123 and improve debug logging

- fix PCF2123_REG_CTRL2 write in pcf2123_shutdown
- improve debugging log (when PCF_LOGGING is defined):
 - dump registers more often
 - dump all 16 regitsers

drivers/rtc/rtc-pcf2123.c

@@ -419,16 +419,17 @@ static int pcf2123_rtc_set_time(struct device *dev, struct rtc_time *tm)
 		(reg) & ~(mask))
 
 int pcf2123_rtc_read_reg_alrm (struct device *dev) {
-	int ret;
-	s8 rxbuf[4];
+	int ret, i=0;
+	u8 rxbuf[16];
 
-	ret = pcf2123_read(dev, PCF2123_REG_ALRM_MN, &rxbuf[0], sizeof(rxbuf));
+	ret = pcf2123_read(dev, 0x0, &rxbuf[0], sizeof(rxbuf));
 	if (ret < 0)
 		return ret;
 	pcf2123_delay_trec();
 
-	printk (KERN_ERR "dump alarm reg:\n %02x  %02x  %02x  %02x\n",
-			rxbuf[0], rxbuf[1], rxbuf[2], rxbuf[3]);
+	printk (KERN_ERR "dump alarm reg:\n");
+	for(i=0;i<16;i++)
+		printk (KERN_ERR "reg: %02x   val: %02x\n", i, rxbuf[i]);
 
 	ret = pcf2123_read(dev, PCF2123_REG_CTRL2, &rxbuf[0], 1);
 	if (ret < 0)
@@ -455,7 +456,9 @@ int pcf2123_rtc_clear_int_alrm (struct device *dev) {
 		return ret;
 	pcf2123_delay_trec();
 
-	//pcf2123_rtc_read_reg_alrm (dev);
+#if PCF_LOGGING
+	pcf2123_rtc_read_reg_alrm (dev);
+#endif
 	return 0;
 }
 
@@ -469,7 +472,7 @@ int pcf2123_rtc_read_alrm (struct device *dev, struct rtc_wkalrm *alrm) {
 		return ret;
 	pcf2123_delay_trec();
 
-	//ret = pcf2123_rtc_read_time (dev, &alrm->time);
+	ret = pcf2123_rtc_read_time (dev, &alrm->time);
 
 	alrm->time.tm_min  = bcd2bin(rxbuf[0] & 0x7F);
 	SET_REG_ALM_EN (alrm->enabled, PCF2123_MASK_ALM_EN_MN, GET_ALM_EN(rxbuf[0]));
@@ -482,6 +485,8 @@ int pcf2123_rtc_read_alrm (struct device *dev, struct rtc_wkalrm *alrm) {
 
 	alrm->enabled &= 0xF;
 
+	dev_dbg(dev, "%s: alrm is enabled=%d\n", __func__,
+			alrm->enabled);
 	dev_dbg(dev, "%s: alrm is mins=%d, hours=%d, mday=%d, wday=%d\n",
 			__func__,
 			alrm->time.tm_min, alrm->time.tm_hour,
@@ -538,6 +543,9 @@ int pcf2123_rtc_set_alrm (struct device *dev, struct rtc_wkalrm *alrm) {
 		return ret;
 	pcf2123_delay_trec();
 
+#if PCF_LOGGING
+	pcf2123_rtc_read_reg_alrm (dev);
+#endif
 
 	/* Set the AIE flag, if needed (enable == 1) */
 
@@ -855,6 +863,7 @@ static ssize_t pcf2123_rtc_sysfs_set_alarm_en (struct device *dev, struct device
 				if (flag != 0 && flag != 1)
 					return -EINVAL;
 				enable = !flag ? enable | (1 << (idx / 2)) : enable & ~(1 << (idx / 2));
+				dev_err(dev, "enable %d\n", enable);
 				buf_ptr++;
 				break;
 			case 1:
@@ -992,6 +1001,7 @@ static int pcf2123_probe(struct spi_device *spi)
 
 	ret = pcf2123_rtc_read_time(&spi->dev, &tm);
 	if (ret < 0) {
+		dev_dbg(&spi->dev, "chip resetted\n");
 		ret = pcf2123_reset(&spi->dev);
 		if (ret < 0) {
 			dev_err(&spi->dev, "chip not found\n");
@@ -1067,6 +1077,9 @@ static int pcf2123_remove(struct spi_device *spi)
 	struct pcf2123_plat_data *pdata = dev_get_platdata(&spi->dev);
 	int i;
 
+#if PCF_LOGGING
+	pcf2123_rtc_read_reg_alrm (&spi->dev);
+#endif
 	if (pdata) {
 		for (i = 0; i < 16; i++)
 			if (pdata->regs[i].name[0])
@@ -1081,11 +1094,14 @@ static void pcf2123_shutdown(struct spi_device *spi) {
 	s8 rxbuf[1];
 	int ret;
 
-	ret = pcf2123_read(&spi->dev, PCF2123_READ, &rxbuf[0], 1);
+	ret = pcf2123_read(&spi->dev, PCF2123_REG_CTRL2, &rxbuf[0], 1);
 	if ( ret < 0 )
 		return;
 		
 	ret = pcf2123_write_reg(&spi->dev, PCF2123_REG_CTRL2, rxbuf[0] & 0xF7);
+#if PCF_LOGGING
+	pcf2123_rtc_read_reg_alrm (&spi->dev);
+#endif
 }
 
 #ifdef CONFIG_OF