Some users may want to read multiple consecutive 8-bit registers. Instead of each caller having to implement the loop, provide a rtc_read8_array() helper. Also, allow a driver to provide a read8_array method, which can be more efficient than reading one register at a time.
Signed-off-by: Rasmus Villemoes <rasmus.villem...@prevas.dk> --- drivers/rtc/rtc-uclass.c | 19 +++++++++++++++++++ include/rtc.h | 24 ++++++++++++++++++++++++ 2 files changed, 43 insertions(+) diff --git a/drivers/rtc/rtc-uclass.c b/drivers/rtc/rtc-uclass.c index a0a238aedd..5070fb416d 100644 --- a/drivers/rtc/rtc-uclass.c +++ b/drivers/rtc/rtc-uclass.c @@ -49,6 +49,25 @@ int rtc_read8(struct udevice *dev, unsigned int reg) return ops->read8(dev, reg); } +int rtc_read8_array(struct udevice *dev, unsigned int reg, + u8 *buf, unsigned int len) +{ + struct rtc_ops *ops = rtc_get_ops(dev); + + assert(ops); + if (ops->read8_array) + return ops->read8_array(dev, reg, buf, len); + if (!ops->read8) + return -ENOSYS; + while (len--) { + int ret = ops->read8(dev, reg++); + if (ret < 0) + return ret; + *buf++ = ret; + } + return 0; +} + int rtc_write8(struct udevice *dev, unsigned int reg, int val) { struct rtc_ops *ops = rtc_get_ops(dev); diff --git a/include/rtc.h b/include/rtc.h index 8aabfc1162..f7f622c1db 100644 --- a/include/rtc.h +++ b/include/rtc.h @@ -64,6 +64,18 @@ struct rtc_ops { */ int (*read8)(struct udevice *dev, unsigned int reg); + /** + * read8_array() - Read multiple 8-bit registers + * + * @dev: Device to read from + * @reg: First register to read + * @buf: Output buffer + * @len: Number of registers to read + * @return 0 if OK, -ve on error + */ + int (*read8_array)(struct udevice *dev, unsigned int reg, + u8 *buf, unsigned int len); + /** * write8() - Write an 8-bit register * @@ -118,6 +130,18 @@ int dm_rtc_reset(struct udevice *dev); */ int rtc_read8(struct udevice *dev, unsigned int reg); +/** + * rtc_read8_array() - Read multiple 8-bit registers + * + * @dev: Device to read from + * @reg: First register to read + * @buf: Output buffer + * @len: Number of registers to read + * @return 0 if OK, -ve on error + */ +int rtc_read8_array(struct udevice *dev, unsigned int reg, + u8 *buf, unsigned int len); + /** * rtc_write8() - Write an 8-bit register * -- 2.23.0