diff --git a/arch/arm/src/stm32/Make.defs b/arch/arm/src/stm32/Make.defs
index 1fc0c18299c225c1453ef76da11189cc6528a1d9..402a3253308b490ea7ccaae51552066aad12afed 100644
--- a/arch/arm/src/stm32/Make.defs
+++ b/arch/arm/src/stm32/Make.defs
@@ -57,7 +57,7 @@ CHIP_CSRCS = stm32_allocateheap.c stm32_start.c stm32_rcc.c stm32_lse.c \
stm32_gpio.c stm32_exti.c stm32_flash.c stm32_irq.c \
stm32_timerisr.c stm32_dma.c stm32_lowputc.c stm32_serial.c \
stm32_spi.c stm32_usbdev.c stm32_sdio.c stm32_tim.c stm32_i2c.c \
- stm32_pwr.c stm32_idle.c stm32_waste.c
+ stm32_idle.c stm32_waste.c
ifeq ($(CONFIG_STM32_ETHMAC),y)
CHIP_CSRCS += stm32_eth.c
@@ -67,6 +67,10 @@ ifeq ($(CONFIG_STM32_RCCLOCK),y)
CHIP_CSRCS += stm32_rcclock.c
endif
+ifeq ($(CONFIG_STM32_PWR),y)
+CHIP_CSRCS += stm32_pwr.c
+endif
+
ifeq ($(CONFIG_RTC),y)
CHIP_CSRCS += stm32_rtc.c
endif
diff --git a/arch/arm/src/stm32/chip/stm32_exti.h b/arch/arm/src/stm32/chip/stm32_exti.h
index 31b50136dad7c889bf4077596528fd077ed88174..d3fb6b3fe2cb306cb4a6562abe282a70cc6f46b8 100644
--- a/arch/arm/src/stm32/chip/stm32_exti.h
+++ b/arch/arm/src/stm32/chip/stm32_exti.h
@@ -99,7 +99,7 @@
# define EXTI_OTGHS_WAKEUP (1 << 20) /* EXTI line 20 is connected to the USB OTG HS Wakeup event */
# define EXTI_RTC_TAMPER (1 << 21) /* EXTI line 21 is connected to the RTC Tamper and TimeStamp events */
# define EXTI_RTC_TIMESTAMP (1 << 22) /* EXTI line 21 is connected to the RTC Tamper and TimeStamp events */
-# define EXTI_RTC_WAKEUP (1 << 23) /* EXTI line 22 is connected to the RTC Wakeup event
+# define EXTI_RTC_WAKEUP (1 << 23) /* EXTI line 22 is connected to the RTC Wakeup event */
#endif
/* Interrupt mask register */
diff --git a/arch/arm/src/stm32/stm32f40xxx_rtc.c b/arch/arm/src/stm32/stm32f40xxx_rtc.c
index e249dc27b4b5d34c519853325b55be1953c582db..7eb1a896b16321cedacbd330cfe9d6a852fe50d9 100644
--- a/arch/arm/src/stm32/stm32f40xxx_rtc.c
+++ b/arch/arm/src/stm32/stm32f40xxx_rtc.c
@@ -43,6 +43,9 @@
#include <nuttx/irq.h>
#include <nuttx/rtc.h>
+#include <time.h>
+#include <errno.h>
+
#include <arch/board/board.h>
#include "up_arch.h"
@@ -61,10 +64,14 @@
# error "CONFIG_RTC_DATETIME must be set to use this driver"
#endif
-#ifndef CONFIG_RTC_HIRES
+#ifdef CONFIG_RTC_HIRES
# error "CONFIG_RTC_HIRES must NOT be set with this driver"
#endif
+#ifndef CONFIG_STM32_PWR
+# error "CONFIG_STM32_PWR must selected to use this driver"
+#endif
+
/* Constants ************************************************************************/
#define SYNCHRO_TIMEOUT (0x00020000)
@@ -226,24 +233,25 @@ static int rtc_enterinit(void)
ret = OK;
if ((regval & RTC_ISR_INITF) == 0)
- {
- /* Set the Initialization mode */
+ {
+ /* Set the Initialization mode */
- putreg32(RTC_ISR_INIT, STM32_RTC_ISR);
+ putreg32(RTC_ISR_INIT, STM32_RTC_ISR);
- /* Wait until the RTC is in the INIT state (or a timeout occurs) */
+ /* Wait until the RTC is in the INIT state (or a timeout occurs) */
- ret = -ETIMEDOUT;
- for (timeout = 0; timeout < INITMODE_TIMEOUT; timeout++)
- {
- regval = getreg32(STM32_RTC_ISR);
- if ((regval & RTC_ISR_INITF) != 0)
- {
- ret = OK;
- break;
- }
- }
-
+ ret = -ETIMEDOUT;
+ for (timeout = 0; timeout < INITMODE_TIMEOUT; timeout++)
+ {
+ regval = getreg32(STM32_RTC_ISR);
+ if ((regval & RTC_ISR_INITF) != 0)
+ {
+ ret = OK;
+ break;
+ }
+ }
+ }
+
return ret;
}
@@ -357,7 +365,7 @@ static int rtc_setup(void)
/* Set Initialization mode */
- ret = rtc_enterinit()
+ ret = rtc_enterinit();
if (ret == OK)
{
/* Set the 24 hour format by clearing the FMT bit in the RTC
@@ -365,7 +373,7 @@ static int rtc_setup(void)
*/
regval = getreg32(STM32_RTC_CR);
- regval &= ~RTC_CR_FMT
+ regval &= ~RTC_CR_FMT;
putreg32(regval, STM32_RTC_CR);
/* Configure RTC pre-scaler to the required, default values for
@@ -405,7 +413,9 @@ static int rtc_setup(void)
static int rtc_resume(void)
{
+#ifdef CONFIG_RTC_ALARM
uint32_t regval;
+#endif
int ret;
/* Wait for the RTC Time and Date registers to be syncrhonized with RTC APB
@@ -473,6 +483,7 @@ static int rtc_interrupt(int irq, void *context)
int up_rtcinitialize(void)
{
uint32_t regval;
+ int ret;
/* Clocking for the PWR block must be provided. However, this is done
* unconditionally in stm32f40xxx_rcc.c on power up. This done unconditionally
@@ -551,7 +562,7 @@ int up_rtcinitialize(void)
*
************************************************************************************/
-int up_rtc_getdatetime(FAR const struct tm *tp)
+int up_rtc_getdatetime(FAR struct tm *tp)
{
uint32_t dr;
uint32_t tr;
@@ -575,13 +586,13 @@ int up_rtc_getdatetime(FAR const struct tm *tp)
* register.
*/
- tmp = (uint8_t)(tr & (RTC_TR_SU_MASK|RTC_TR_ST_MASK)) >> RTC_TR_SU_SHIFT;
+ tmp = (tr & (RTC_TR_SU_MASK|RTC_TR_ST_MASK)) >> RTC_TR_SU_SHIFT;
tp->tm_sec = rtc_bcd2bin(tmp);
- tmp = (tr & RTC_TR_MNU_MASK|RTC_TR_MNT_MASK) >> RTC_TR_MNU_SHIFT;
+ tmp = (tr & (RTC_TR_MNU_MASK|RTC_TR_MNT_MASK)) >> RTC_TR_MNU_SHIFT;
tp->tm_min = rtc_bcd2bin(tmp);
- tmp = (tr & RTC_TR_HU_MASK|RTC_TR_HT_MASK) >> RTC_TR_HU_SHIFT;
+ tmp = (tr & (RTC_TR_HU_MASK|RTC_TR_HT_MASK)) >> RTC_TR_HU_SHIFT;
tp->tm_hour = rtc_bcd2bin(tmp);
/* Now convert the RTC date to fields in struct tm format:
@@ -593,13 +604,13 @@ int up_rtc_getdatetime(FAR const struct tm *tp)
* years 2000-2099? I'll assume so.
*/
- tmp = (dr & RTC_DR_DU_MASK|RTC_DR_DT_MASK) >> RTC_DR_DU_SHIFT;
+ tmp = (dr & (RTC_DR_DU_MASK|RTC_DR_DT_MASK)) >> RTC_DR_DU_SHIFT;
tp->tm_mday = rtc_bcd2bin(tmp);
- tmp = (dr & RTC_DR_MU_MASK|RTC_DR_MT) >> RTC_DR_MU_SHIFT;
+ tmp = (dr & (RTC_DR_MU_MASK|RTC_DR_MT)) >> RTC_DR_MU_SHIFT;
tp->tm_mon = rtc_bcd2bin(tmp) - 1;
- tmp = (dr & RTC_DR_YU_MASK|RTC_DR_YT_MASK) >> RTC_DR_YU_SHIFT; /* Year units, BCD 0-99 */
+ tmp = (dr & (RTC_DR_YU_MASK|RTC_DR_YT_MASK)) >> RTC_DR_YU_SHIFT;
tp->tm_year = rtc_bcd2bin(tmp) + 100;
return OK;
}
@@ -637,9 +648,9 @@ int up_rtc_settime(FAR const struct timespec *tp)
* register.
*/
- tr = (rtc_bin2bcd(tp->tm_sec) << RTC_TR_SU_SHIFT) |
- (rtc_bin2bcd(tp->tm_min) << RTC_TR_MNU_SHIFT) |
- (rtc_bin2bcd(tp->tm_hour) << RTC_TR_HU_SHIFT);
+ tr = (rtc_bin2bcd(newtime.tm_sec) << RTC_TR_SU_SHIFT) |
+ (rtc_bin2bcd(newtime.tm_min) << RTC_TR_MNU_SHIFT) |
+ (rtc_bin2bcd(newtime.tm_hour) << RTC_TR_HU_SHIFT);
tr &= ~RTC_TR_RESERVED_BITS;
/* Now convert the fields in struct tm format to the RTC date register fields:
@@ -651,9 +662,9 @@ int up_rtc_settime(FAR const struct timespec *tp)
* years 2000-2099? I'll assume so.
*/
- dr = (rtc_bin2bcd(tp->tm_mday) << RTC_DR_DU_SHIFT) |
- ((rtc_bin2bcd(tp->tm_mon) + 1) << RTC_DR_MU_SHIFT) |
- ((rtc_bin2bcd(tp->tm_year) - 100) << RTC_DR_YU_SHIFT);
+ dr = (rtc_bin2bcd(newtime.tm_mday) << RTC_DR_DU_SHIFT) |
+ ((rtc_bin2bcd(newtime.tm_mon) + 1) << RTC_DR_MU_SHIFT) |
+ ((rtc_bin2bcd(newtime.tm_year) - 100) << RTC_DR_YU_SHIFT);
dr &= ~RTC_DR_RESERVED_BITS;
/* Disable the write protection for RTC registers */
@@ -662,7 +673,7 @@ int up_rtc_settime(FAR const struct timespec *tp)
/* Set Initialization mode */
- ret = rtc_enterinit()
+ ret = rtc_enterinit();
if (ret == OK)
{
/* Set the RTC TR and DR registers */
@@ -674,7 +685,7 @@ int up_rtc_settime(FAR const struct timespec *tp)
* registers to be synchronized with RTC APB clock.
*/
- rtc_enterinit()
+ rtc_exitinit();
ret = rtc_synchwait();
}
diff --git a/configs/README.txt b/configs/README.txt
index 46b41d1aba72d38ce524f2f742c43de73a95daed..3ed5d256353a932cffc0a31a760cad9f124975c4 100644
--- a/configs/README.txt
+++ b/configs/README.txt
@@ -609,20 +609,29 @@ defconfig -- This is a configuration file similar to the Linux
RTC
- CONFIG_RTC - Enables general support for a hardware RTC. Specific
+ CONFIG_RTC - Enables general support for a hardware RTC. Specific
architectures may require other specific settings.
- CONFIG_RTC_HIRES - The typical RTC keeps time to resolution of 1
- second, usually supporting a 32-bit time_t value. In this case,
- the RTC is used to "seed" the normal NuttX timer and the
- NuttX timer provides for higher resoution time. If CONFIG_RTC_HIRES
- is enabled in the NuttX configuration, then the RTC provides higher
- resolution time and completely replaces the system timer for purpose of
- date and time.
- CONFIG_RTC_FREQUENCY - If CONFIG_RTC_HIRES is defined, then the
- frequency of the high resolution RTC must be provided. If CONFIG_RTC_HIRES
- is not defined, CONFIG_RTC_FREQUENCY is assumed to be one.
- CONFIG_RTC_ALARM - Enable if the RTC hardware supports setting of an alarm.
- A callback function will be executed when the alarm goes off
+ CONFIG_RTC_DATETIME - There are two general types of RTC: (1) A simple
+ battery backed counter that keeps the time when power is down, and (2)
+ A full date / time RTC the provides the date and time information, often
+ in BCD format. If CONFIG_RTC_DATETIME is selected, it specifies this
+ second kind of RTC. In this case, the RTC is used to "seed" the normal
+ NuttX timer and the NuttX system timer provides for higher resoution
+ time.
+ CONFIG_RTC_HIRES - If CONFIG_RTC_DATETIME not selected, then the simple,
+ battery backed counter is used. There are two different implementations
+ of such simple counters based on the time resolution of the counter:
+ The typical RTC keeps time to resolution of 1 second, usually
+ supporting a 32-bit time_t value. In this case, the RTC is used to
+ "seed" the normal NuttX timer and the NuttX timer provides for higher
+ resoution time. If CONFIG_RTC_HIRES is enabled in the NuttX configuration,
+ then the RTC provides higher resolution time and completely replaces the
+ system timer for purpose of date and time.
+ CONFIG_RTC_FREQUENCY - If CONFIG_RTC_HIRES is defined, then the frequency
+ of the high resolution RTC must be provided. If CONFIG_RTC_HIRES is
+ not defined, CONFIG_RTC_FREQUENCY is assumed to be one.
+ CONFIG_RTC_ALARM - Enable if the RTC hardware supports setting of an
+ alarm. A callback function will be executed when the alarm goes off
SPI driver
diff --git a/configs/stm3240g-eval/README.txt b/configs/stm3240g-eval/README.txt
index a840e16991e60426607003739e1306c1d01a3d76..3368ef1fb7caf9c2f7b3bf260e709db9eb6f2411 100755
--- a/configs/stm3240g-eval/README.txt
+++ b/configs/stm3240g-eval/README.txt
@@ -335,6 +335,7 @@ STM3240G-EVAL-specific Configuration Options
CONFIG_STM32_CAN1
CONFIG_STM32_CAN2
CONFIG_STM32_DAC
+ CONFIG_STM32_PWR -- Required for RTC
APB2
----
diff --git a/configs/stm3240g-eval/dhcpd/defconfig b/configs/stm3240g-eval/dhcpd/defconfig
index a3bdd3f32ea836e82e452cbd5cdabd9b8f67c879..c2f3440f39f62d60b0239dd7789999f38b182de0 100755
--- a/configs/stm3240g-eval/dhcpd/defconfig
+++ b/configs/stm3240g-eval/dhcpd/defconfig
@@ -161,6 +161,7 @@ CONFIG_STM32_I2C3=n
CONFIG_STM32_CAN1=n
CONFIG_STM32_CAN2=n
CONFIG_STM32_DAC=n
+CONFIG_STM32_PWR=n
# APB2:
CONFIG_STM32_TIM1=n
CONFIG_STM32_TIM8=n
@@ -754,6 +755,39 @@ CONFIG_NET_BROADCAST=y
CONFIG_NET_DHCP_LIGHT=n
CONFIG_NET_RESOLV_ENTRIES=4
+#
+# RTC Configuration
+#
+# CONFIG_RTC - Enables general support for a hardware RTC. Specific
+# architectures may require other specific settings.
+# CONFIG_RTC_DATETIME - There are two general types of RTC: (1) A simple
+# battery backed counter that keeps the time when power is down, and (2)
+# A full date / time RTC the provides the date and time information, often
+# in BCD format. If CONFIG_RTC_DATETIME is selected, it specifies this
+# second kind of RTC. In this case, the RTC is used to "seed" the normal
+# NuttX timer and the NuttX system timer provides for higher resoution
+# time.
+# CONFIG_RTC_HIRES - If CONFIG_RTC_DATETIME not selected, then the simple,
+# battery backed counter is used. There are two different implementations
+# of such simple counters based on the time resolution of the counter:
+# The typical RTC keeps time to resolution of 1 second, usually
+# supporting a 32-bit time_t value. In this case, the RTC is used to
+# "seed" the normal NuttX timer and the NuttX timer provides for higher
+# resoution time. If CONFIG_RTC_HIRES is enabled in the NuttX configuration,
+# then the RTC provides higher resolution time and completely replaces the
+# system timer for purpose of date and time.
+# CONFIG_RTC_FREQUENCY - If CONFIG_RTC_HIRES is defined, then the frequency
+# of the high resolution RTC must be provided. If CONFIG_RTC_HIRES is
+# not defined, CONFIG_RTC_FREQUENCY is assumed to be one.
+# CONFIG_RTC_ALARM - Enable if the RTC hardware supports setting of an
+# alarm. A callback function will be executed when the alarm goes off
+#
+CONFIG_RTC=n
+CONFIG_RTC_DATETIME=y
+CONFIG_RTC_HIRES=n
+CONFIG_RTC_FREQUENCY=n
+CONFIG_RTC_ALARM=n
+
#
# USB Device Configuration
#
diff --git a/configs/stm3240g-eval/nettest/defconfig b/configs/stm3240g-eval/nettest/defconfig
index 7399ea9ed4a2a16828fd9f478ecfc2f64e965571..94b8075db947733a9aba1134f5ac9b326dc4efd5 100755
--- a/configs/stm3240g-eval/nettest/defconfig
+++ b/configs/stm3240g-eval/nettest/defconfig
@@ -161,6 +161,7 @@ CONFIG_STM32_I2C3=n
CONFIG_STM32_CAN1=n
CONFIG_STM32_CAN2=n
CONFIG_STM32_DAC=n
+CONFIG_STM32_PWR=n
# APB2:
CONFIG_STM32_TIM1=n
CONFIG_STM32_TIM8=n
@@ -754,6 +755,39 @@ CONFIG_NET_BROADCAST=n
CONFIG_NET_DHCP_LIGHT=n
CONFIG_NET_RESOLV_ENTRIES=4
+#
+# RTC Configuration
+#
+# CONFIG_RTC - Enables general support for a hardware RTC. Specific
+# architectures may require other specific settings.
+# CONFIG_RTC_DATETIME - There are two general types of RTC: (1) A simple
+# battery backed counter that keeps the time when power is down, and (2)
+# A full date / time RTC the provides the date and time information, often
+# in BCD format. If CONFIG_RTC_DATETIME is selected, it specifies this
+# second kind of RTC. In this case, the RTC is used to "seed" the normal
+# NuttX timer and the NuttX system timer provides for higher resoution
+# time.
+# CONFIG_RTC_HIRES - If CONFIG_RTC_DATETIME not selected, then the simple,
+# battery backed counter is used. There are two different implementations
+# of such simple counters based on the time resolution of the counter:
+# The typical RTC keeps time to resolution of 1 second, usually
+# supporting a 32-bit time_t value. In this case, the RTC is used to
+# "seed" the normal NuttX timer and the NuttX timer provides for higher
+# resoution time. If CONFIG_RTC_HIRES is enabled in the NuttX configuration,
+# then the RTC provides higher resolution time and completely replaces the
+# system timer for purpose of date and time.
+# CONFIG_RTC_FREQUENCY - If CONFIG_RTC_HIRES is defined, then the frequency
+# of the high resolution RTC must be provided. If CONFIG_RTC_HIRES is
+# not defined, CONFIG_RTC_FREQUENCY is assumed to be one.
+# CONFIG_RTC_ALARM - Enable if the RTC hardware supports setting of an
+# alarm. A callback function will be executed when the alarm goes off
+#
+CONFIG_RTC=n
+CONFIG_RTC_DATETIME=y
+CONFIG_RTC_HIRES=n
+CONFIG_RTC_FREQUENCY=n
+CONFIG_RTC_ALARM=n
+
#
# USB Device Configuration
#
diff --git a/configs/stm3240g-eval/nsh/defconfig b/configs/stm3240g-eval/nsh/defconfig
index cc98db02aa227ebce711fdcf9609f4cb620c5dc3..ca378376030cc1fded31d50e05f7d60da625e66c 100755
--- a/configs/stm3240g-eval/nsh/defconfig
+++ b/configs/stm3240g-eval/nsh/defconfig
@@ -161,6 +161,7 @@ CONFIG_STM32_I2C3=n
CONFIG_STM32_CAN1=n
CONFIG_STM32_CAN2=n
CONFIG_STM32_DAC=n
+CONFIG_STM32_PWR=n
# APB2:
CONFIG_STM32_TIM1=n
CONFIG_STM32_TIM8=n
@@ -758,6 +759,39 @@ CONFIG_NET_BROADCAST=n
CONFIG_NET_DHCP_LIGHT=n
CONFIG_NET_RESOLV_ENTRIES=4
+#
+# RTC Configuration
+#
+# CONFIG_RTC - Enables general support for a hardware RTC. Specific
+# architectures may require other specific settings.
+# CONFIG_RTC_DATETIME - There are two general types of RTC: (1) A simple
+# battery backed counter that keeps the time when power is down, and (2)
+# A full date / time RTC the provides the date and time information, often
+# in BCD format. If CONFIG_RTC_DATETIME is selected, it specifies this
+# second kind of RTC. In this case, the RTC is used to "seed" the normal
+# NuttX timer and the NuttX system timer provides for higher resoution
+# time.
+# CONFIG_RTC_HIRES - If CONFIG_RTC_DATETIME not selected, then the simple,
+# battery backed counter is used. There are two different implementations
+# of such simple counters based on the time resolution of the counter:
+# The typical RTC keeps time to resolution of 1 second, usually
+# supporting a 32-bit time_t value. In this case, the RTC is used to
+# "seed" the normal NuttX timer and the NuttX timer provides for higher
+# resoution time. If CONFIG_RTC_HIRES is enabled in the NuttX configuration,
+# then the RTC provides higher resolution time and completely replaces the
+# system timer for purpose of date and time.
+# CONFIG_RTC_FREQUENCY - If CONFIG_RTC_HIRES is defined, then the frequency
+# of the high resolution RTC must be provided. If CONFIG_RTC_HIRES is
+# not defined, CONFIG_RTC_FREQUENCY is assumed to be one.
+# CONFIG_RTC_ALARM - Enable if the RTC hardware supports setting of an
+# alarm. A callback function will be executed when the alarm goes off
+#
+CONFIG_RTC=n
+CONFIG_RTC_DATETIME=y
+CONFIG_RTC_HIRES=n
+CONFIG_RTC_FREQUENCY=n
+CONFIG_RTC_ALARM=n
+
#
# USB Device Configuration
#
diff --git a/configs/stm3240g-eval/ostest/defconfig b/configs/stm3240g-eval/ostest/defconfig
index f45820bf9fb094d1ef4f48e0212a37568f6f200b..8acda4c6bfd7ede902a25b3b8eca334a9f2d4b4e 100755
--- a/configs/stm3240g-eval/ostest/defconfig
+++ b/configs/stm3240g-eval/ostest/defconfig
@@ -161,6 +161,7 @@ CONFIG_STM32_I2C3=n
CONFIG_STM32_CAN1=n
CONFIG_STM32_CAN2=n
CONFIG_STM32_DAC=n
+CONFIG_STM32_PWR=n
# APB2:
CONFIG_STM32_TIM1=n
CONFIG_STM32_TIM8=n
@@ -714,6 +715,39 @@ CONFIG_NET_BROADCAST=n
CONFIG_NET_DHCP_LIGHT=n
CONFIG_NET_RESOLV_ENTRIES=4
+#
+# RTC Configuration
+#
+# CONFIG_RTC - Enables general support for a hardware RTC. Specific
+# architectures may require other specific settings.
+# CONFIG_RTC_DATETIME - There are two general types of RTC: (1) A simple
+# battery backed counter that keeps the time when power is down, and (2)
+# A full date / time RTC the provides the date and time information, often
+# in BCD format. If CONFIG_RTC_DATETIME is selected, it specifies this
+# second kind of RTC. In this case, the RTC is used to "seed" the normal
+# NuttX timer and the NuttX system timer provides for higher resoution
+# time.
+# CONFIG_RTC_HIRES - If CONFIG_RTC_DATETIME not selected, then the simple,
+# battery backed counter is used. There are two different implementations
+# of such simple counters based on the time resolution of the counter:
+# The typical RTC keeps time to resolution of 1 second, usually
+# supporting a 32-bit time_t value. In this case, the RTC is used to
+# "seed" the normal NuttX timer and the NuttX timer provides for higher
+# resoution time. If CONFIG_RTC_HIRES is enabled in the NuttX configuration,
+# then the RTC provides higher resolution time and completely replaces the
+# system timer for purpose of date and time.
+# CONFIG_RTC_FREQUENCY - If CONFIG_RTC_HIRES is defined, then the frequency
+# of the high resolution RTC must be provided. If CONFIG_RTC_HIRES is
+# not defined, CONFIG_RTC_FREQUENCY is assumed to be one.
+# CONFIG_RTC_ALARM - Enable if the RTC hardware supports setting of an
+# alarm. A callback function will be executed when the alarm goes off
+#
+CONFIG_RTC=n
+CONFIG_RTC_DATETIME=y
+CONFIG_RTC_HIRES=n
+CONFIG_RTC_FREQUENCY=n
+CONFIG_RTC_ALARM=n
+
#
# USB Device Configuration
#
diff --git a/include/nuttx/rtc.h b/include/nuttx/rtc.h
index 30aa7ce85ee7bd3bda4544f12961cc17f189cbbd..46a7c8a2ffe7caaa1ea988383682ff5e6af2cfa9 100644
--- a/include/nuttx/rtc.h
+++ b/include/nuttx/rtc.h
@@ -217,7 +217,7 @@ EXTERN int up_rtc_gettime(FAR struct timespec *tp);
************************************************************************************/
#ifdef CONFIG_RTC_DATETIME
-EXTERN int up_rtc_getdatetime(FAR const struct tm *tp);
+EXTERN int up_rtc_getdatetime(FAR struct tm *tp);
#endif
/************************************************************************************