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, 199 insertions, 0 deletions

diff --git a/drivers/input/misc/gpio-vibra.c b/drivers/input/misc/gpio-vibra.c
new file mode 100644
index 000000000..ad44b4d18
--- /dev/null
+++ b/drivers/input/misc/gpio-vibra.c
@@ -0,0 +1,199 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ *  GPIO vibrator driver
+ *
+ *  Copyright (C) 2019 Luca Weiss <luca@z3ntu.xyz>
+ *
+ *  Based on PWM vibrator driver:
+ *  Copyright (C) 2017 Collabora Ltd.
+ *
+ *  Based on previous work from:
+ *  Copyright (C) 2012 Dmitry Torokhov <dmitry.torokhov@gmail.com>
+ *
+ *  Based on PWM beeper driver:
+ *  Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
+ */
+
+#include <linux/gpio/consumer.h>
+#include <linux/input.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+struct gpio_vibrator {
+	struct input_dev *input;
+	struct gpio_desc *gpio;
+	struct regulator *vcc;
+
+	struct work_struct play_work;
+	bool running;
+	bool vcc_on;
+};
+
+static int gpio_vibrator_start(struct gpio_vibrator *vibrator)
+{
+	struct device *pdev = vibrator->input->dev.parent;
+	int err;
+
+	if (!vibrator->vcc_on) {
+		err = regulator_enable(vibrator->vcc);
+		if (err) {
+			dev_err(pdev, "failed to enable regulator: %d\n", err);
+			return err;
+		}
+		vibrator->vcc_on = true;
+	}
+
+	gpiod_set_value_cansleep(vibrator->gpio, 1);
+
+	return 0;
+}
+
+static void gpio_vibrator_stop(struct gpio_vibrator *vibrator)
+{
+	gpiod_set_value_cansleep(vibrator->gpio, 0);
+
+	if (vibrator->vcc_on) {
+		regulator_disable(vibrator->vcc);
+		vibrator->vcc_on = false;
+	}
+}
+
+static void gpio_vibrator_play_work(struct work_struct *work)
+{
+	struct gpio_vibrator *vibrator =
+		container_of(work, struct gpio_vibrator, play_work);
+
+	if (vibrator->running)
+		gpio_vibrator_start(vibrator);
+	else
+		gpio_vibrator_stop(vibrator);
+}
+
+static int gpio_vibrator_play_effect(struct input_dev *dev, void *data,
+				     struct ff_effect *effect)
+{
+	struct gpio_vibrator *vibrator = input_get_drvdata(dev);
+	int level;
+
+	level = effect->u.rumble.strong_magnitude;
+	if (!level)
+		level = effect->u.rumble.weak_magnitude;
+
+	vibrator->running = level;
+	schedule_work(&vibrator->play_work);
+
+	return 0;
+}
+
+static void gpio_vibrator_close(struct input_dev *input)
+{
+	struct gpio_vibrator *vibrator = input_get_drvdata(input);
+
+	cancel_work_sync(&vibrator->play_work);
+	gpio_vibrator_stop(vibrator);
+	vibrator->running = false;
+}
+
+static int gpio_vibrator_probe(struct platform_device *pdev)
+{
+	struct gpio_vibrator *vibrator;
+	int err;
+
+	vibrator = devm_kzalloc(&pdev->dev, sizeof(*vibrator), GFP_KERNEL);
+	if (!vibrator)
+		return -ENOMEM;
+
+	vibrator->input = devm_input_allocate_device(&pdev->dev);
+	if (!vibrator->input)
+		return -ENOMEM;
+
+	vibrator->vcc = devm_regulator_get(&pdev->dev, "vcc");
+	if (IS_ERR(vibrator->vcc))
+		return dev_err_probe(&pdev->dev, PTR_ERR(vibrator->vcc),
+				     "Failed to request regulator\n");
+
+	vibrator->gpio = devm_gpiod_get(&pdev->dev, "enable", GPIOD_OUT_LOW);
+	if (IS_ERR(vibrator->gpio))
+		return dev_err_probe(&pdev->dev, PTR_ERR(vibrator->gpio),
+				     "Failed to request main gpio\n");
+
+	INIT_WORK(&vibrator->play_work, gpio_vibrator_play_work);
+
+	vibrator->input->name = "gpio-vibrator";
+	vibrator->input->id.bustype = BUS_HOST;
+	vibrator->input->close = gpio_vibrator_close;
+
+	input_set_drvdata(vibrator->input, vibrator);
+	input_set_capability(vibrator->input, EV_FF, FF_RUMBLE);
+
+	err = input_ff_create_memless(vibrator->input, NULL,
+				      gpio_vibrator_play_effect);
+	if (err) {
+		dev_err(&pdev->dev, "Couldn't create FF dev: %d\n", err);
+		return err;
+	}
+
+	err = input_register_device(vibrator->input);
+	if (err) {
+		dev_err(&pdev->dev, "Couldn't register input dev: %d\n", err);
+		return err;
+	}
+
+	platform_set_drvdata(pdev, vibrator);
+
+	return 0;
+}
+
+static int gpio_vibrator_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct gpio_vibrator *vibrator = platform_get_drvdata(pdev);
+
+	cancel_work_sync(&vibrator->play_work);
+	if (vibrator->running)
+		gpio_vibrator_stop(vibrator);
+
+	return 0;
+}
+
+static int gpio_vibrator_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct gpio_vibrator *vibrator = platform_get_drvdata(pdev);
+
+	if (vibrator->running)
+		gpio_vibrator_start(vibrator);
+
+	return 0;
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(gpio_vibrator_pm_ops,
+				gpio_vibrator_suspend, gpio_vibrator_resume);
+
+#ifdef CONFIG_OF
+static const struct of_device_id gpio_vibra_dt_match_table[] = {
+	{ .compatible = "gpio-vibrator" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, gpio_vibra_dt_match_table);
+#endif
+
+static struct platform_driver gpio_vibrator_driver = {
+	.probe	= gpio_vibrator_probe,
+	.driver	= {
+		.name	= "gpio-vibrator",
+		.pm	= pm_sleep_ptr(&gpio_vibrator_pm_ops),
+		.of_match_table = of_match_ptr(gpio_vibra_dt_match_table),
+	},
+};
+module_platform_driver(gpio_vibrator_driver);
+
+MODULE_AUTHOR("Luca Weiss <luca@z3ntu.xy>");
+MODULE_DESCRIPTION("GPIO vibrator driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:gpio-vibrator");