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>

3 files changed, 126 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/trigger-source/adi,util-sigma-delta-spi.yaml b/Documentation/devicetree/bindings/trigger-source/adi,util-sigma-delta-spi.yaml
new file mode 100644
index 000000000..ea4661795
--- /dev/null
+++ b/Documentation/devicetree/bindings/trigger-source/adi,util-sigma-delta-spi.yaml
@@ -0,0 +1,49 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+# Copyright (c) 2025 Analog Devices, Inc.
+# Copyright (c) 2025 BayLibre, SAS
+
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/trigger-source/adi,util-sigma-delta-spi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Analog Devices Util Sigma-Delta SPI IP Core
+
+maintainers:
+  - David Lechner <dlechner@baylibre.com>
+
+description:
+  The Util Sigma-Delta SPI is an FPGA IP core from Analog Devices that provides
+  a SPI offload trigger from the RDY signal of the combined DOUT/RDY pin of
+  the sigma-delta family of ADCs.
+  https://analogdevicesinc.github.io/hdl/library/util_sigma_delta_spi/index.html
+
+properties:
+  compatible:
+    const: adi,util-sigma-delta-spi
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  '#trigger-source-cells':
+    const: 0
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - '#trigger-source-cells'
+
+additionalProperties: false
+
+examples:
+  - |
+    trigger@40000 {
+        reg = <0x40000 0x1000>;
+        compatible = "adi,util-sigma-delta-spi";
+        clocks = <&clk 0>;
+        #trigger-source-cells = <0>;
+    };
diff --git a/Documentation/devicetree/bindings/trigger-source/gpio-trigger.yaml b/Documentation/devicetree/bindings/trigger-source/gpio-trigger.yaml
new file mode 100644
index 000000000..1331d153e
--- /dev/null
+++ b/Documentation/devicetree/bindings/trigger-source/gpio-trigger.yaml
@@ -0,0 +1,40 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/trigger-source/gpio-trigger.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Generic trigger source using GPIO
+
+description: A GPIO used as a trigger source.
+
+maintainers:
+  - Jonathan Santos <Jonathan.Santos@analog.com>
+
+properties:
+  compatible:
+    const: gpio-trigger
+
+  '#trigger-source-cells':
+    const: 0
+
+  gpios:
+    maxItems: 1
+    description: GPIO to be used as a trigger source.
+
+required:
+  - compatible
+  - '#trigger-source-cells'
+  - gpios
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    trigger {
+        compatible = "gpio-trigger";
+        #trigger-source-cells = <0>;
+        gpios = <&gpio1 15 GPIO_ACTIVE_HIGH>;
+    };
diff --git a/Documentation/devicetree/bindings/trigger-source/pwm-trigger.yaml b/Documentation/devicetree/bindings/trigger-source/pwm-trigger.yaml
new file mode 100644
index 000000000..1eac20031
--- /dev/null
+++ b/Documentation/devicetree/bindings/trigger-source/pwm-trigger.yaml
@@ -0,0 +1,37 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/trigger-source/pwm-trigger.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Generic trigger source using PWM
+
+description: Remaps a PWM channel as a trigger source.
+
+maintainers:
+  - David Lechner <dlechner@baylibre.com>
+
+properties:
+  compatible:
+    const: pwm-trigger
+
+  '#trigger-source-cells':
+    const: 0
+
+  pwms:
+    maxItems: 1
+
+required:
+  - compatible
+  - '#trigger-source-cells'
+  - pwms
+
+additionalProperties: false
+
+examples:
+  - |
+    trigger {
+        compatible = "pwm-trigger";
+        #trigger-source-cells = <0>;
+        pwms = <&pwm 0 1000000 0>;
+    };