iio: proximity: vl53l0x-i2c: claim direct mode for raw readsgrafted

vl53l0x_read_raw() starts a single-shot ranging measurement and reads
back the result. Once the triggered buffer is enabled the sensor runs in
continuous mode and its data-ready interrupt is routed to the trigger,
so a concurrent in_distance_raw read disturbs the streaming setup and
never gets its completion, returning -ETIMEDOUT.

The original submission claimed direct mode here, but it was dropped
during review because the driver had no buffer support at the time [1].
Continuous (buffered) mode was later added without restoring the
claim [2], reintroducing the conflict.

Reject direct reads while buffered capture is active by claiming direct
mode around the measurement, as the vl53l1x sibling already does.

Fixes: 762186c6e7b1 ("iio: proximity: vl53l0x-i2c: Added continuous mode support")
Link: https://lore.kernel.org/linux-iio/20180911160300.GA9212@himanshu-Vostro-3559/ [1]
Link: https://lore.kernel.org/linux-iio/20240909101508.263085-3-abhashkumarjha123@gmail.com/ [2]
Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>

1 files changed, 17 insertions, 0 deletions

diff --git a/Documentation/firmware_class/hotplug-script b/Documentation/firmware_class/hotplug-script
new file mode 100644
index 000000000..8143a950b
--- /dev/null
+++ b/Documentation/firmware_class/hotplug-script
@@ -0,0 +1,17 @@
+#!/bin/sh
+
+# Simple hotplug script sample:
+# 
+# Both $DEVPATH and $FIRMWARE are already provided in the environment.
+
+HOTPLUG_FW_DIR=/usr/lib/hotplug/firmware/
+
+if [ "$SUBSYSTEM" == "firmware" -a "$ACTION" == "add" ]; then
+  if [ -f $HOTPLUG_FW_DIR/$FIRMWARE ]; then
+    echo 1 > /sys/$DEVPATH/loading
+    cat $HOTPLUG_FW_DIR/$FIRMWARE > /sys/$DEVPATH/data
+    echo 0 > /sys/$DEVPATH/loading
+  else
+    echo -1 > /sys/$DEVPATH/loading
+  fi
+fi