rtc-cmos driver: add wakeup and day of month support

BZ: 144574

This patch adds two configurable features to the rtc-cmos driver:
 - if CONFIG_RTC_DRV_CMOS_WAKEUP_FROM_LPSTATES is set then driver will
add alarm wakeup capability from S3 (suspend to RAM) and S4/5 (OFF).
 - if CONFIG_RTC_DRV_CMOS_DAYOFMONTH_ALARM is set on top of the above
flag then alarm wakeup from low power states will be supported up to
one month instead of only one day. Day of month is set in RTC CMOS
register D.

This patch comes as part of the overall wakeup from OFF feature
supported on Intel mobile platforms.

Change-Id: I94d56710f570d58be1806c1642f1fa6722d3e3dc
Signed-off-by: Gabriel Touzeau <gabrielx.touzeau@intel.com>
Reviewed-on: https://android.intel.com/425802
Reviewed-by: Wood, Brian J <brian.j.wood@intel.com>
Tested-by: Wood, Brian J <brian.j.wood@intel.com>
Reviewed-by: Noziska, Patrick J <patrick.j.noziska@intel.com>

2 files changed, 35 insertions, 2 deletions

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index b9838130a7b..fe9640c3149 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -614,6 +614,20 @@ config RTC_DRV_CMOS
 	  This driver can also be built as a module. If so, the module
 	  will be called rtc-cmos.
 
+config RTC_DRV_CMOS_WAKEUP_FROM_LPSTATES
+	tristate "PC-style 'CMOS' can wakeup from low power states"
+	depends on RTC_DRV_CMOS
+	help
+	  Say "yes" to have rtc-cmos driver capability to wakeup from low
+	  power states (S3 and S4/5).
+
+config RTC_DRV_CMOS_DAYOFMONTH_ALARM
+	tristate "PC-style 'CMOS' supports day of month for alarms"
+	depends on RTC_DRV_CMOS_WAKEUP_FROM_LPSTATES
+	help
+	  Say "yes" to have rtc-cmos driver support day of month for
+	  alarms through REG_D register.
+
 config RTC_DRV_VRTC
 	tristate "Virtual RTC for Intel MID platforms"
 	depends on X86_INTEL_MID
diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
index 204d529ef22..459bdadac76 100644
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -729,8 +729,10 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
 	hpet_set_periodic_freq(cmos_rtc.rtc->irq_freq);
 	CMOS_WRITE(RTC_REF_CLCK_32KHZ | 0x06, RTC_FREQ_SELECT);
 
+#ifndef CONFIG_RTC_DRV_CMOS_WAKEUP_FROM_LPSTATES
 	/* disable irqs */
 	cmos_irq_disable(&cmos_rtc, RTC_PIE | RTC_AIE | RTC_UIE);
+#endif
 
 	rtc_control = CMOS_READ(RTC_CONTROL);
 
@@ -1023,12 +1025,27 @@ static void cmos_wake_setup(struct device *dev)
 	device_init_wakeup(dev, 1);
 }
 
-#elif defined(CONFIG_X86_INTEL_MID)
+#elif defined(CONFIG_RTC_DRV_CMOS_WAKEUP_FROM_LPSTATES)
+
+#ifdef	CONFIG_RTC_DRV_CMOS_DAYOFMONTH_ALARM
+static struct cmos_rtc_board_info cmos_wakeup_rtc_info;
+#endif
 
 static void cmos_wake_setup(struct device *dev)
 {
+#ifdef	CONFIG_RTC_DRV_CMOS_DAYOFMONTH_ALARM
+	/* add day of month capability for alarms */
+	cmos_wakeup_rtc_info.rtc_day_alarm = RTC_REG_D;
+	cmos_wakeup_rtc_info.rtc_mon_alarm = 0;
+	cmos_wakeup_rtc_info.rtc_century = 0;
+
+	cmos_wakeup_rtc_info.wake_on = NULL;
+	cmos_wakeup_rtc_info.wake_off = NULL;
+
+	dev->platform_data = &cmos_wakeup_rtc_info;
+#endif
+
 	/* RTC always wakes from S1/S2/S3, and often S4/STD */
-	/* on all Intel MID platforms using legacy RTC */
 	device_init_wakeup(dev, 1);
 }
 
@@ -1177,10 +1194,12 @@ static int __exit cmos_platform_remove(struct platform_device *pdev)
 
 static void cmos_platform_shutdown(struct platform_device *pdev)
 {
+#ifndef CONFIG_RTC_DRV_CMOS_WAKEUP_FROM_LPSTATES
 	if (system_state == SYSTEM_POWER_OFF && !cmos_poweroff(&pdev->dev))
 		return;
 
 	cmos_do_shutdown();
+#endif
 }
 
 /* work with hotplug and coldplug */