diff options
Diffstat (limited to 'include/linux/iopoll.h')
-rw-r--r-- | include/linux/iopoll.h | 80 |
1 files changed, 65 insertions, 15 deletions
diff --git a/include/linux/iopoll.h b/include/linux/iopoll.h index 35e15dfd4155..2c8860e406bd 100644 --- a/include/linux/iopoll.h +++ b/include/linux/iopoll.h @@ -14,36 +14,41 @@ #include <linux/io.h> /** - * 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 + * read_poll_timeout - Periodically poll an address until a condition is + * met or a timeout occurs + * @op: accessor function (takes @args as its arguments) * @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 + * @sleep_before_read: if it is true, sleep @sleep_us before read. + * @args: arguments for @op poll * * Returns 0 on success and -ETIMEDOUT upon a timeout. In either - * case, the last read value at @addr is stored in @val. Must not + * case, the last read value at @args 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) \ +#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) \ @@ -53,42 +58,87 @@ }) /** - * 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) - * @addr: Address to poll + * read_poll_timeout_atomic - Periodically poll an address until a condition is + * met or a timeout occurs + * @op: accessor function (takes @args as its arguments) * @val: Variable to read the value into * @cond: Break condition (usually involving @val) * @delay_us: Time to udelay between reads in us (0 tight-loops). Should * be less than ~10us since udelay is used (see * Documentation/timers/timers-howto.rst). * @timeout_us: Timeout in us, 0 means never timeout + * @delay_before_read: if it is true, delay @delay_us before read. + * @args: arguments for @op poll * * Returns 0 on success and -ETIMEDOUT upon a timeout. In either - * case, the last read value at @addr is stored in @val. + * case, the last read value at @args is stored in @val. * * When available, you'll probably want to use one of the specialized * macros defined below rather than this macro directly. */ -#define readx_poll_timeout_atomic(op, addr, val, cond, delay_us, timeout_us) \ +#define read_poll_timeout_atomic(op, val, cond, delay_us, timeout_us, \ + delay_before_read, args...) \ ({ \ u64 __timeout_us = (timeout_us); \ unsigned long __delay_us = (delay_us); \ ktime_t __timeout = ktime_add_us(ktime_get(), __timeout_us); \ + if (delay_before_read && __delay_us) \ + udelay(__delay_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 (__delay_us) \ - udelay(__delay_us); \ + udelay(__delay_us); \ } \ (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) + * @addr: Address to poll + * @val: Variable to read the value into + * @cond: Break condition (usually involving @val) + * @delay_us: Time to udelay between reads in us (0 tight-loops). Should + * be less than ~10us since udelay 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. + * + * When available, you'll probably want to use one of the specialized + * macros defined below rather than this macro directly. + */ +#define readx_poll_timeout_atomic(op, addr, val, cond, delay_us, timeout_us) \ + read_poll_timeout_atomic(op, val, cond, delay_us, timeout_us, false, addr) #define readb_poll_timeout(addr, val, cond, delay_us, timeout_us) \ readx_poll_timeout(readb, addr, val, cond, delay_us, timeout_us) |