mirror of
https://github.com/torvalds/linux.git
synced 2026-04-27 11:02:31 -04:00
00423c4a7d
Add i915_jiffies.h and intel_display_jiffies.h for jiffies timeout and wait helpers, and use them separately from i915 and display. This helps reduce the display dependency on i915_utils.h. Long term, both msecs_to_jiffies_timeout() and wait_remaining_ms_from_jiffies() really belong in core kernel headers, but for now unblock display refactoring. Reviewed-by: Luca Coelho <luciano.coelho@intel.com> Link: https://patch.msgid.link/d8bc62b3a81afa05c849dde9b0f633572eaf5611.1761146196.git.jani.nikula@intel.com Signed-off-by: Jani Nikula <jani.nikula@intel.com>
44 lines
1.3 KiB
C
44 lines
1.3 KiB
C
/* SPDX-License-Identifier: MIT */
|
|
/* Copyright © 2025 Intel Corporation */
|
|
|
|
#ifndef __INTEL_DISPLAY_JIFFIES_H__
|
|
#define __INTEL_DISPLAY_JIFFIES_H__
|
|
|
|
#include <linux/jiffies.h>
|
|
|
|
static inline unsigned long msecs_to_jiffies_timeout(const unsigned int m)
|
|
{
|
|
unsigned long j = msecs_to_jiffies(m);
|
|
|
|
return min_t(unsigned long, MAX_JIFFY_OFFSET, j + 1);
|
|
}
|
|
|
|
/*
|
|
* If you need to wait X milliseconds between events A and B, but event B
|
|
* doesn't happen exactly after event A, you record the timestamp (jiffies) of
|
|
* when event A happened, then just before event B you call this function and
|
|
* pass the timestamp as the first argument, and X as the second argument.
|
|
*/
|
|
static inline void
|
|
wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies, int to_wait_ms)
|
|
{
|
|
unsigned long target_jiffies, tmp_jiffies, remaining_jiffies;
|
|
|
|
/*
|
|
* Don't re-read the value of "jiffies" every time since it may change
|
|
* behind our back and break the math.
|
|
*/
|
|
tmp_jiffies = jiffies;
|
|
target_jiffies = timestamp_jiffies +
|
|
msecs_to_jiffies_timeout(to_wait_ms);
|
|
|
|
if (time_after(target_jiffies, tmp_jiffies)) {
|
|
remaining_jiffies = target_jiffies - tmp_jiffies;
|
|
while (remaining_jiffies)
|
|
remaining_jiffies =
|
|
schedule_timeout_uninterruptible(remaining_jiffies);
|
|
}
|
|
}
|
|
|
|
#endif /* __INTEL_DISPLAY_JIFFIES_H__ */
|