From d8be08805bc03d53b0dd6953792fba543a4f3890 Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Mon, 6 Jul 2020 22:01:10 +0200 Subject: [PATCH] rtc: add dm_rtc_read helper and ->read method Some users may want to read multiple consecutive 8-bit registers. Instead of each caller having to implement the loop, provide a dm_rtc_read() helper. Also, allow a driver to provide a ->read method, which can be more efficient than reading one register at a time. Reviewed-by: Simon Glass Reviewed-by: Heiko Schocher Signed-off-by: Rasmus Villemoes --- drivers/rtc/rtc-uclass.c | 19 +++++++++++++++++++ include/rtc.h | 23 +++++++++++++++++++++++ 2 files changed, 42 insertions(+) diff --git a/drivers/rtc/rtc-uclass.c b/drivers/rtc/rtc-uclass.c index 926cca234e..4a0e3c5643 100644 --- a/drivers/rtc/rtc-uclass.c +++ b/drivers/rtc/rtc-uclass.c @@ -40,6 +40,25 @@ int dm_rtc_reset(struct udevice *dev) return ops->reset(dev); } +int dm_rtc_read(struct udevice *dev, unsigned int reg, u8 *buf, unsigned int len) +{ + struct rtc_ops *ops = rtc_get_ops(dev); + + assert(ops); + if (ops->read) + return ops->read(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_read8(struct udevice *dev, unsigned int reg) { struct rtc_ops *ops = rtc_get_ops(dev); diff --git a/include/rtc.h b/include/rtc.h index 8aabfc1162..f30e908221 100644 --- a/include/rtc.h +++ b/include/rtc.h @@ -55,6 +55,18 @@ struct rtc_ops { */ int (*reset)(struct udevice *dev); + /** + * read() - 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 (*read)(struct udevice *dev, unsigned int reg, + u8 *buf, unsigned int len); + /** * read8() - Read an 8-bit register * @@ -109,6 +121,17 @@ int dm_rtc_set(struct udevice *dev, struct rtc_time *time); */ int dm_rtc_reset(struct udevice *dev); +/** + * dm_rtc_read() - 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 dm_rtc_read(struct udevice *dev, unsigned int reg, u8 *buf, unsigned int len); + /** * rtc_read8() - Read an 8-bit register * -- 2.39.5