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, 98 insertions, 0 deletions

diff --git a/drivers/input/misc/88pm886-onkey.c b/drivers/input/misc/88pm886-onkey.c
new file mode 100644
index 000000000..284ff5190
--- /dev/null
+++ b/drivers/input/misc/88pm886-onkey.c
@@ -0,0 +1,98 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include <linux/mfd/88pm886.h>
+
+struct pm886_onkey {
+	struct input_dev *idev;
+	struct pm886_chip *chip;
+};
+
+static irqreturn_t pm886_onkey_irq_handler(int irq, void *data)
+{
+	struct pm886_onkey *onkey = data;
+	struct regmap *regmap = onkey->chip->regmap;
+	struct input_dev *idev = onkey->idev;
+	struct device *parent = idev->dev.parent;
+	unsigned int val;
+	int err;
+
+	err = regmap_read(regmap, PM886_REG_STATUS1, &val);
+	if (err) {
+		dev_err(parent, "Failed to read status: %d\n", err);
+		return IRQ_NONE;
+	}
+	val &= PM886_ONKEY_STS1;
+
+	input_report_key(idev, KEY_POWER, val);
+	input_sync(idev);
+
+	return IRQ_HANDLED;
+}
+
+static int pm886_onkey_probe(struct platform_device *pdev)
+{
+	struct pm886_chip *chip = dev_get_drvdata(pdev->dev.parent);
+	struct device *dev = &pdev->dev;
+	struct pm886_onkey *onkey;
+	struct input_dev *idev;
+	int irq, err;
+
+	onkey = devm_kzalloc(dev, sizeof(*onkey), GFP_KERNEL);
+	if (!onkey)
+		return -ENOMEM;
+
+	onkey->chip = chip;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return dev_err_probe(dev, irq, "Failed to get IRQ\n");
+
+	idev = devm_input_allocate_device(dev);
+	if (!idev) {
+		dev_err(dev, "Failed to allocate input device\n");
+		return -ENOMEM;
+	}
+	onkey->idev = idev;
+
+	idev->name = "88pm886-onkey";
+	idev->phys = "88pm886-onkey/input0";
+	idev->id.bustype = BUS_I2C;
+
+	input_set_capability(idev, EV_KEY, KEY_POWER);
+
+	err = devm_request_threaded_irq(dev, irq, NULL, pm886_onkey_irq_handler,
+					IRQF_ONESHOT | IRQF_NO_SUSPEND, "onkey",
+					onkey);
+	if (err)
+		return dev_err_probe(dev, err, "Failed to request IRQ\n");
+
+	err = input_register_device(idev);
+	if (err)
+		return dev_err_probe(dev, err, "Failed to register input device\n");
+
+	return 0;
+}
+
+static const struct platform_device_id pm886_onkey_id_table[] = {
+	{ "88pm886-onkey", },
+	{ }
+};
+MODULE_DEVICE_TABLE(platform, pm886_onkey_id_table);
+
+static struct platform_driver pm886_onkey_driver = {
+	.driver = {
+		.name = "88pm886-onkey",
+	},
+	.probe = pm886_onkey_probe,
+	.id_table = pm886_onkey_id_table,
+};
+module_platform_driver(pm886_onkey_driver);
+
+MODULE_DESCRIPTION("Marvell 88PM886 onkey driver");
+MODULE_AUTHOR("Karel Balej <balejk@matfyz.cz>");
+MODULE_LICENSE("GPL");