From dbeda5b2255089889788e0dd3478680feec86139 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Mon, 20 Apr 2015 12:37:23 -0600 Subject: dm: rtc: Add a uclass for real-time clocks Add a uclass for real-time clocks which support getting the current time, setting it and resetting the chip to a known-working state. Some RTCs have additional registers which can be used to store settings, so also provide an interface to these. Signed-off-by: Simon Glass --- include/dm/uclass-id.h | 1 + include/rtc.h | 132 +++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 133 insertions(+) (limited to 'include') diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h index 395e25a431..08f1bad938 100644 --- a/include/dm/uclass-id.h +++ b/include/dm/uclass-id.h @@ -46,6 +46,7 @@ enum uclass_id { UCLASS_USB_DEV_GENERIC, /* USB generic device */ UCLASS_MASS_STORAGE, /* Mass storage device */ UCLASS_CPU, /* CPU, typically part of an SoC */ + UCLASS_RTC, /* Real time clock device */ UCLASS_COUNT, UCLASS_INVALID = -1, diff --git a/include/rtc.h b/include/rtc.h index 2566c83b81..bd8621d60b 100644 --- a/include/rtc.h +++ b/include/rtc.h @@ -17,6 +17,137 @@ #include #include +#ifdef CONFIG_DM_RTC + +struct rtc_ops { + /** + * get() - get the current time + * + * Returns the current time read from the RTC device. The driver + * is responsible for setting up every field in the structure. + * + * @dev: Device to read from + * @time: Place to put the time that is read + */ + int (*get)(struct udevice *dev, struct rtc_time *time); + + /** + * set() - set the current time + * + * Sets the time in the RTC device. The driver can expect every + * field to be set correctly. + * + * @dev: Device to read from + * @time: Time to write + */ + int (*set)(struct udevice *dev, const struct rtc_time *time); + + /** + * reset() - reset the RTC to a known-good state + * + * This function resets the RTC to a known-good state. The time may + * be unset by this method, so should be set after this method is + * called. + * + * @dev: Device to read from + * @return 0 if OK, -ve on error + */ + int (*reset)(struct udevice *dev); + + /** + * read8() - Read an 8-bit register + * + * @dev: Device to read from + * @reg: Register to read + * @return value read, or -ve on error + */ + int (*read8)(struct udevice *dev, unsigned int reg); + + /** + * write8() - Write an 8-bit register + * + * @dev: Device to write to + * @reg: Register to write + * @value: Value to write + * @return 0 if OK, -ve on error + */ + int (*write8)(struct udevice *dev, unsigned int reg, int val); +}; + +/* Access the operations for an RTC device */ +#define rtc_get_ops(dev) ((struct rtc_ops *)(dev)->driver->ops) + +/** + * dm_rtc_get() - Read the time from an RTC + * + * @dev: Device to read from + * @time: Place to put the current time + * @return 0 if OK, -ve on error + */ +int dm_rtc_get(struct udevice *dev, struct rtc_time *time); + +/** + * dm_rtc_put() - Write a time to an RTC + * + * @dev: Device to read from + * @time: Time to write into the RTC + * @return 0 if OK, -ve on error + */ +int dm_rtc_set(struct udevice *dev, struct rtc_time *time); + +/** + * dm_rtc_reset() - reset the RTC to a known-good state + * + * If the RTC appears to be broken (e.g. it is not counting up in seconds) + * it may need to be reset to a known good state. This function achieves this. + * After resetting the RTC the time should then be set to a known value by + * the caller. + * + * @dev: Device to read from + * @return 0 if OK, -ve on error + */ +int dm_rtc_reset(struct udevice *dev); + +/** + * rtc_read8() - Read an 8-bit register + * + * @dev: Device to read from + * @reg: Register to read + * @return value read, or -ve on error + */ +int rtc_read8(struct udevice *dev, unsigned int reg); + +/** + * rtc_write8() - Write an 8-bit register + * + * @dev: Device to write to + * @reg: Register to write + * @value: Value to write + * @return 0 if OK, -ve on error + */ +int rtc_write8(struct udevice *dev, unsigned int reg, int val); + +/** + * rtc_read32() - Read a 32-bit value from the RTC + * + * @dev: Device to read from + * @reg: Offset to start reading from + * @valuep: Place to put the value that is read + * @return 0 if OK, -ve on error + */ +int rtc_read32(struct udevice *dev, unsigned int reg, u32 *valuep); + +/** + * rtc_write32() - Write a 32-bit value to the RTC + * + * @dev: Device to write to + * @reg: Register to start writing to + * @value: Value to write + * @return 0 if OK, -ve on error + */ +int rtc_write32(struct udevice *dev, unsigned int reg, u32 value); + +#else int rtc_get (struct rtc_time *); int rtc_set (struct rtc_time *); void rtc_reset (void); @@ -57,6 +188,7 @@ void rtc_write32(int reg, u32 value); * rtc_init() - Set up the real time clock ready for use */ void rtc_init(void); +#endif /** * rtc_calc_weekday() - Work out the weekday from a time -- cgit v1.2.3