aboutsummaryrefslogtreecommitdiffstats
path: root/include/linux/regmap.h
diff options
context:
space:
mode:
authorRodrigo Vivi <rodrigo.vivi@intel.com>2020-02-25 09:29:58 -0800
committerRodrigo Vivi <rodrigo.vivi@intel.com>2020-02-25 09:39:23 -0800
commitff36e78fdb251b9fa65028554689806961e011eb (patch)
treef5af925d509224e06a10936196be6c06bcbdc6ae /include/linux/regmap.h
parentdrm/i915: Drop assertion that active->fence is unchanged (diff)
parentMerge tag 'drm-misc-next-2020-02-10' of git://anongit.freedesktop.org/drm/drm-misc into drm-next (diff)
downloadlinux-dev-ff36e78fdb251b9fa65028554689806961e011eb.tar.xz
linux-dev-ff36e78fdb251b9fa65028554689806961e011eb.zip
Merge drm/drm-next into drm-intel-next-queued
Some DSI and VBT pending patches from Hans will apply cleanly and with less ugly conflicts if they are rebuilt on top of other patches that recently landed on drm-next. Reference: https://patchwork.freedesktop.org/series/70952/ Cc: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com
Diffstat (limited to 'include/linux/regmap.h')
-rw-r--r--include/linux/regmap.h45
1 files changed, 45 insertions, 0 deletions
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index dfe493ac692d..f0a092a1a96d 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -145,6 +145,51 @@ 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.
+ *
+ * Note: In general regmap cannot be used in atomic context. If you want to use
+ * this macro then first setup your regmap for atomic use (flat or no cache
+ * and MMIO regmap).
+ */
+#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