This patch adds a macro 'regmap_read_poll_timeout_atomic' that works
similar to 'readx_poll_timeout_atomic' defined in linux/iopoll.h; This
is atomic version of already available 'regmap_read_poll_timeout' macro.
Signed-off-by: Sameer Pujar <spujar@xxxxxxxxxx>
---
include/linux/regmap.h | 41 +++++++++++++++++++++++++++++++++++++++++
1 file changed, 41 insertions(+)
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index dfe493a..09d79ea 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -145,6 +145,47 @@ struct reg_sequence {
})
/**
+ * regmap_read_poll_timeout_atomic - Poll until a condition is met or a timeout occurs
+ *
+ * @map: Regmap to read from
+ * @addr: Address to poll
+ * @val: Unsigned integer 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 or the regmap_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.
+ *
+ * This is modelled after the readx_poll_timeout_atomic macros in linux/iopoll.h.
+ */
+#define regmap_read_poll_timeout_atomic(map, addr, val, cond, delay_us, timeout_us) \
+({ \
+ u64 __timeout_us = (timeout_us); \
+ unsigned long __delay_us = (delay_us); \
+ ktime_t __timeout = ktime_add_us(ktime_get(), __timeout_us); \
+ int __ret; \
+ for (;;) { \
+ __ret = regmap_read((map), (addr), &(val)); \
+ if (__ret) \
+ break; \
+ if (cond) \
+ break; \
+ if ((__timeout_us) && \
+ ktime_compare(ktime_get(), __timeout) > 0) { \
+ __ret = regmap_read((map), (addr), &(val)); \
+ break; \
+ } \
+ if (__delay_us) \
+ udelay(__delay_us); \
+ } \
+ __ret ?: ((cond) ? 0 : -ETIMEDOUT); \
+})
+
+/**
* regmap_field_read_poll_timeout - Poll until a condition is met or timeout
*
* @field: Regmap field to read from
--
2.7.4
