2 * Wait for bit with timeout and ctrlc
4 * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
6 * SPDX-License-Identifier: GPL-2.0+
14 #include <asm/errno.h>
18 * wait_for_bit() waits for bit set/cleared in register
20 * Function polls register waiting for specific bit(s) change
21 * (either 0->1 or 1->0). It can fail under two conditions:
23 * - User interaction (CTRL-C)
24 * Function succeeds only if all bits of masked register are set/cleared
25 * (depending on set option).
27 * @param prefix Prefix added to timeout messagge (message visible only
29 * @param reg Register that will be read (using readl())
30 * @param mask Bit(s) of register that must be active
31 * @param set Selects wait condition (bit set or clear)
32 * @param timeout_ms Timeout (in miliseconds)
33 * @param breakable Enables CTRL-C interruption
34 * @return 0 on success, -ETIMEDOUT or -EINTR on failure
36 static inline int wait_for_bit(const char *prefix, const u32 *reg,
37 const u32 mask, const bool set,
38 const unsigned int timeout_ms,
42 unsigned long start = get_timer(0);
50 if ((val & mask) == mask)
53 if (get_timer(start) > timeout_ms)
56 if (breakable && ctrlc()) {
64 debug("%s: Timeout (reg=%p mask=%08x wait_set=%i)\n", prefix, reg, mask,