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| author | Neil Armstrong <narmstrong@baylibre.com> | 2018-11-22 11:01:03 +0100 |
|---|---|---|
| committer | Jagan Teki <jagan@amarulasolutions.com> | 2018-11-24 14:41:11 +0530 |
| commit | d13801ef1d14fe46f97630b56e01200b337dad6c (patch) | |
| tree | dbe871d31bd3bf95d3bed37cf07379d09266d754 | |
| parent | d821e5edfb8023dc01baa8e1fc0487485f313db2 (diff) | |
| download | u-boot-d13801ef1d14fe46f97630b56e01200b337dad6c.zip u-boot-d13801ef1d14fe46f97630b56e01200b337dad6c.tar.gz u-boot-d13801ef1d14fe46f97630b56e01200b337dad6c.tar.bz2 | |
regmap: add regmap_read_poll_timeout() helper
Add the regmap_read_poll_timeout() macro based on the Linux implementation
to simplify register polling with configurable timeout and sleep.
Tested-by: Jerome Brunet <jbrunet@baylibre.com>
Acked-by: Jagan Teki <jagan@openedev.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
| -rw-r--r-- | include/regmap.h | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/include/regmap.h b/include/regmap.h index b2b733f..a3afb72 100644 --- a/include/regmap.h +++ b/include/regmap.h @@ -240,6 +240,44 @@ int regmap_raw_read_range(struct regmap *map, uint range_num, uint offset, regmap_range_get(map, 0, type, member, valp) /** + * regmap_read_poll_timeout - Poll until a condition is met or a timeout occurs + * + * @map: Regmap to read from + * @addr: Offset to poll + * @val: Unsigned integer variable to read the value into + * @cond: Break condition (usually involving @val) + * @sleep_us: Maximum time to sleep between reads in us (0 tight-loops). + * @timeout_ms: Timeout in ms, 0 means never timeout + * + * Returns 0 on success and -ETIMEDOUT upon a timeout or the regmap_read + * error return value in case of a error read. In the two former cases, + * the last read value at @addr is stored in @val. Must not be called + * from atomic context if sleep_us or timeout_us are used. + * + * This is modelled after the regmap_read_poll_timeout macros in linux but + * with millisecond timeout. + */ +#define regmap_read_poll_timeout(map, addr, val, cond, sleep_us, timeout_ms) \ +({ \ + unsigned long __start = get_timer(0); \ + int __ret; \ + for (;;) { \ + __ret = regmap_read((map), (addr), &(val)); \ + if (__ret) \ + break; \ + if (cond) \ + break; \ + if ((timeout_ms) && get_timer(__start) > (timeout_ms)) { \ + __ret = regmap_read((map), (addr), &(val)); \ + break; \ + } \ + if ((sleep_us)) \ + udelay((sleep_us)); \ + } \ + __ret ?: ((cond) ? 0 : -ETIMEDOUT); \ +}) + +/** * regmap_update_bits() - Perform a read/modify/write using a mask * * @map: The map returned by regmap_init_mem*() |