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, 144 insertions, 0 deletions

diff --git a/drivers/acpi/fan_attr.c b/drivers/acpi/fan_attr.c
new file mode 100644
index 000000000..9b7fa52f3
--- /dev/null
+++ b/drivers/acpi/fan_attr.c
@@ -0,0 +1,144 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  fan_attr.c - Create extra attributes for ACPI Fan driver
+ *
+ *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
+ *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ *  Copyright (C) 2022 Intel Corporation. All rights reserved.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/acpi.h>
+
+#include "fan.h"
+
+MODULE_LICENSE("GPL");
+
+static ssize_t show_state(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct acpi_fan_fps *fps = container_of(attr, struct acpi_fan_fps, dev_attr);
+	int count;
+
+	if (fps->control == 0xFFFFFFFF || fps->control > 100)
+		count = sysfs_emit(buf, "not-defined:");
+	else
+		count = sysfs_emit(buf, "%lld:", fps->control);
+
+	if (fps->trip_point == 0xFFFFFFFF || fps->trip_point > 9)
+		count += sysfs_emit_at(buf, count, "not-defined:");
+	else
+		count += sysfs_emit_at(buf, count, "%lld:", fps->trip_point);
+
+	if (fps->speed == 0xFFFFFFFF)
+		count += sysfs_emit_at(buf, count, "not-defined:");
+	else
+		count += sysfs_emit_at(buf, count, "%lld:", fps->speed);
+
+	if (fps->noise_level == 0xFFFFFFFF)
+		count += sysfs_emit_at(buf, count, "not-defined:");
+	else
+		count += sysfs_emit_at(buf, count, "%lld:", fps->noise_level * 100);
+
+	if (fps->power == 0xFFFFFFFF)
+		count += sysfs_emit_at(buf, count, "not-defined\n");
+	else
+		count += sysfs_emit_at(buf, count, "%lld\n", fps->power);
+
+	return count;
+}
+
+static ssize_t show_fan_speed(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct acpi_device *acpi_dev = container_of(dev, struct acpi_device, dev);
+	struct acpi_fan_fst fst;
+	int status;
+
+	status = acpi_fan_get_fst(acpi_dev->handle, &fst);
+	if (status)
+		return status;
+
+	return sysfs_emit(buf, "%lld\n", fst.speed);
+}
+
+static ssize_t show_fine_grain_control(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct acpi_device *acpi_dev = container_of(dev, struct acpi_device, dev);
+	struct acpi_fan *fan = acpi_driver_data(acpi_dev);
+
+	return sysfs_emit(buf, "%d\n", fan->fif.fine_grain_ctrl);
+}
+
+int acpi_fan_create_attributes(struct acpi_device *device)
+{
+	struct acpi_fan *fan = acpi_driver_data(device);
+	int i, status;
+
+	/* _FST is present if we are here */
+	sysfs_attr_init(&fan->fst_speed.attr);
+	fan->fst_speed.show = show_fan_speed;
+	fan->fst_speed.store = NULL;
+	fan->fst_speed.attr.name = "fan_speed_rpm";
+	fan->fst_speed.attr.mode = 0444;
+	status = sysfs_create_file(&device->dev.kobj, &fan->fst_speed.attr);
+	if (status)
+		return status;
+
+	if (!fan->acpi4)
+		return 0;
+
+	sysfs_attr_init(&fan->fine_grain_control.attr);
+	fan->fine_grain_control.show = show_fine_grain_control;
+	fan->fine_grain_control.store = NULL;
+	fan->fine_grain_control.attr.name = "fine_grain_control";
+	fan->fine_grain_control.attr.mode = 0444;
+	status = sysfs_create_file(&device->dev.kobj, &fan->fine_grain_control.attr);
+	if (status)
+		goto rem_fst_attr;
+
+	for (i = 0; i < fan->fps_count; ++i) {
+		struct acpi_fan_fps *fps = &fan->fps[i];
+
+		snprintf(fps->name, ACPI_FPS_NAME_LEN, "state%d", i);
+		sysfs_attr_init(&fps->dev_attr.attr);
+		fps->dev_attr.show = show_state;
+		fps->dev_attr.store = NULL;
+		fps->dev_attr.attr.name = fps->name;
+		fps->dev_attr.attr.mode = 0444;
+		status = sysfs_create_file(&device->dev.kobj, &fps->dev_attr.attr);
+		if (status) {
+			int j;
+
+			for (j = 0; j < i; ++j)
+				sysfs_remove_file(&device->dev.kobj, &fan->fps[j].dev_attr.attr);
+			goto rem_fine_grain_attr;
+		}
+	}
+
+	return 0;
+
+rem_fine_grain_attr:
+	sysfs_remove_file(&device->dev.kobj, &fan->fine_grain_control.attr);
+
+rem_fst_attr:
+	sysfs_remove_file(&device->dev.kobj, &fan->fst_speed.attr);
+
+	return status;
+}
+
+void acpi_fan_delete_attributes(struct acpi_device *device)
+{
+	struct acpi_fan *fan = acpi_driver_data(device);
+	int i;
+
+	sysfs_remove_file(&device->dev.kobj, &fan->fst_speed.attr);
+
+	if (!fan->acpi4)
+		return;
+
+	for (i = 0; i < fan->fps_count; ++i)
+		sysfs_remove_file(&device->dev.kobj, &fan->fps[i].dev_attr.attr);
+
+	sysfs_remove_file(&device->dev.kobj, &fan->fine_grain_control.attr);
+}