The patch regmap: add iopoll-like polling macro for regmap_field has been applied to the regmap tree at git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap.git All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark >From 667063acb81931e2f8fd0cb91df9fcccad131d9a Mon Sep 17 00:00:00 2001 From: Chen-Yu Tsai <wens@xxxxxxxx> Date: Fri, 29 Sep 2017 16:23:01 +0800 Subject: [PATCH] regmap: add iopoll-like polling macro for regmap_field This patch adds a macro regmap_field_read_poll_timeout that works similar to the readx_poll_timeout defined in linux/iopoll.h, except that this can also return the error value returned by a failed regmap_field_read. Signed-off-by: Chen-Yu Tsai <wens@xxxxxxxx> Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> --- include/linux/regmap.h | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/include/linux/regmap.h b/include/linux/regmap.h index 978abfbac617..93a4663d7acb 100644 --- a/include/linux/regmap.h +++ b/include/linux/regmap.h @@ -139,6 +139,45 @@ struct reg_sequence { pollret ?: ((cond) ? 0 : -ETIMEDOUT); \ }) +/** + * regmap_field_read_poll_timeout - Poll until a condition is met or timeout + * + * @field: Regmap field to read from + * @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). Should be less than ~20ms since usleep_range + * is used (see Documentation/timers/timers-howto.txt). + * @timeout_us: Timeout in us, 0 means never timeout + * + * Returns 0 on success and -ETIMEDOUT upon a timeout or the regmap_field_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 readx_poll_timeout macros in linux/iopoll.h. + */ +#define regmap_field_read_poll_timeout(field, val, cond, sleep_us, timeout_us) \ +({ \ + ktime_t timeout = ktime_add_us(ktime_get(), timeout_us); \ + int pollret; \ + might_sleep_if(sleep_us); \ + for (;;) { \ + pollret = regmap_field_read((field), &(val)); \ + if (pollret) \ + break; \ + if (cond) \ + break; \ + if (timeout_us && ktime_compare(ktime_get(), timeout) > 0) { \ + pollret = regmap_field_read((field), &(val)); \ + break; \ + } \ + if (sleep_us) \ + usleep_range((sleep_us >> 2) + 1, sleep_us); \ + } \ + pollret ?: ((cond) ? 0 : -ETIMEDOUT); \ +}) + #ifdef CONFIG_REGMAP enum regmap_endian { -- 2.14.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html