| From 2be6a2d4eaa4db01d3afbd5e9d6fd15494a87f2f Mon Sep 17 00:00:00 2001 |
| From: Bo Jiao <Bo.Jiao@mediatek.com> |
| Date: Fri, 17 Jun 2022 11:23:57 +0800 |
| Subject: [PATCH 2/8] 9991-add-read-poll-timeout-function-for-kernel5.4 |
| |
| --- |
| include/linux/iopoll.h | 30 +++++++++++++++++++++++++++--- |
| 1 file changed, 27 insertions(+), 3 deletions(-) |
| mode change 100644 => 100755 include/linux/iopoll.h |
| |
| diff --git a/include/linux/iopoll.h b/include/linux/iopoll.h |
| old mode 100644 |
| new mode 100755 |
| index 35e15dfd4..d96087008 |
| --- a/include/linux/iopoll.h |
| +++ b/include/linux/iopoll.h |
| @@ -31,19 +31,22 @@ |
| * When available, you'll probably want to use one of the specialized |
| * macros defined below rather than this macro directly. |
| */ |
| -#define readx_poll_timeout(op, addr, val, cond, sleep_us, timeout_us) \ |
| +#define read_poll_timeout(op, val, cond, sleep_us, timeout_us, \ |
| + sleep_before_read, args...) \ |
| ({ \ |
| u64 __timeout_us = (timeout_us); \ |
| unsigned long __sleep_us = (sleep_us); \ |
| ktime_t __timeout = ktime_add_us(ktime_get(), __timeout_us); \ |
| might_sleep_if((__sleep_us) != 0); \ |
| + if (sleep_before_read && __sleep_us) \ |
| + usleep_range((__sleep_us >> 2) + 1, __sleep_us); \ |
| for (;;) { \ |
| - (val) = op(addr); \ |
| + (val) = op(args); \ |
| if (cond) \ |
| break; \ |
| if (__timeout_us && \ |
| ktime_compare(ktime_get(), __timeout) > 0) { \ |
| - (val) = op(addr); \ |
| + (val) = op(args); \ |
| break; \ |
| } \ |
| if (__sleep_us) \ |
| @@ -52,6 +55,27 @@ |
| (cond) ? 0 : -ETIMEDOUT; \ |
| }) |
| |
| +/** |
| + * readx_poll_timeout - Periodically poll an address until a condition is met or a timeout occurs |
| + * @op: accessor function (takes @addr as its only argument) |
| + * @addr: Address to poll |
| + * @val: 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.rst). |
| + * @timeout_us: Timeout in us, 0 means never timeout |
| + * |
| + * Returns 0 on success and -ETIMEDOUT upon a timeout. In either |
| + * case, 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. |
| + * |
| + * When available, you'll probably want to use one of the specialized |
| + * macros defined below rather than this macro directly. |
| + */ |
| +#define readx_poll_timeout(op, addr, val, cond, sleep_us, timeout_us) \ |
| + read_poll_timeout(op, val, cond, sleep_us, timeout_us, false, addr) |
| + |
| /** |
| * readx_poll_timeout_atomic - Periodically poll an address until a condition is met or a timeout occurs |
| * @op: accessor function (takes @addr as its only argument) |
| -- |
| 2.18.0 |
| |