iio: proximity: isl29501: Fix return type of isl29501_register_writegrafted

isl29501_register_write() was returning a u32 instead of an int.
Since the function returns negative error codes (such as -ERANGE or
return values from i2c_smbus_write_byte_data()), returning an unsigned
integer type prevents callers from correctly checking for negative error
conditions.

Fix this by changing the function return type from u32 to int.

This was found through manual code review.

Fixes: 1c28799257bc ("iio: light: isl29501: Add support for the ISL29501 ToF sensor.")
Signed-off-by: Salah Triki <salah.triki@gmail.com>
Reviewed-by: Joshua Crofts <joshua.crofts1@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>

1 files changed, 156 insertions, 0 deletions

diff --git a/drivers/input/touchscreen/ipaq-micro-ts.c b/drivers/input/touchscreen/ipaq-micro-ts.c
new file mode 100644
index 000000000..243e6465d
--- /dev/null
+++ b/drivers/input/touchscreen/ipaq-micro-ts.c
@@ -0,0 +1,156 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * h3600 atmel micro companion support, touchscreen subdevice
+ * Author : Alessandro Gardich <gremlin@gremlin.it>
+ * Author : Dmitry Artamonow <mad_soft@inbox.ru>
+ * Author : Linus Walleij <linus.walleij@linaro.org>
+ */
+
+#include <asm/byteorder.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/pm.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/input.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/mfd/ipaq-micro.h>
+
+struct touchscreen_data {
+	struct input_dev *input;
+	struct ipaq_micro *micro;
+};
+
+static void micro_ts_receive(void *data, int len, unsigned char *msg)
+{
+	struct touchscreen_data *ts = data;
+
+	if (len == 4) {
+		input_report_abs(ts->input, ABS_X,
+				 be16_to_cpup((__be16 *) &msg[2]));
+		input_report_abs(ts->input, ABS_Y,
+				 be16_to_cpup((__be16 *) &msg[0]));
+		input_report_key(ts->input, BTN_TOUCH, 1);
+		input_sync(ts->input);
+	} else if (len == 0) {
+		input_report_abs(ts->input, ABS_X, 0);
+		input_report_abs(ts->input, ABS_Y, 0);
+		input_report_key(ts->input, BTN_TOUCH, 0);
+		input_sync(ts->input);
+	}
+}
+
+static void micro_ts_toggle_receive(struct touchscreen_data *ts, bool enable)
+{
+	struct ipaq_micro *micro = ts->micro;
+
+	guard(spinlock_irq)(&micro->lock);
+
+	if (enable) {
+		micro->ts = micro_ts_receive;
+		micro->ts_data = ts;
+	} else {
+		micro->ts = NULL;
+		micro->ts_data = NULL;
+	}
+}
+
+static int micro_ts_open(struct input_dev *input)
+{
+	struct touchscreen_data *ts = input_get_drvdata(input);
+
+	micro_ts_toggle_receive(ts, true);
+
+	return 0;
+}
+
+static void micro_ts_close(struct input_dev *input)
+{
+	struct touchscreen_data *ts = input_get_drvdata(input);
+
+	micro_ts_toggle_receive(ts, false);
+}
+
+static int micro_ts_probe(struct platform_device *pdev)
+{
+	struct ipaq_micro *micro = dev_get_drvdata(pdev->dev.parent);
+	struct touchscreen_data *ts;
+	int error;
+
+	ts = devm_kzalloc(&pdev->dev, sizeof(*ts), GFP_KERNEL);
+	if (!ts)
+		return -ENOMEM;
+
+	ts->micro = micro;
+
+	ts->input = devm_input_allocate_device(&pdev->dev);
+	if (!ts->input) {
+		dev_err(&pdev->dev, "failed to allocate input device\n");
+		return -ENOMEM;
+	}
+
+	ts->input->name = "ipaq micro ts";
+	ts->input->open = micro_ts_open;
+	ts->input->close = micro_ts_close;
+
+	input_set_drvdata(ts->input, ts);
+
+	input_set_capability(ts->input, EV_KEY, BTN_TOUCH);
+	input_set_capability(ts->input, EV_ABS, ABS_X);
+	input_set_capability(ts->input, EV_ABS, ABS_Y);
+	input_set_abs_params(ts->input, ABS_X, 0, 1023, 0, 0);
+	input_set_abs_params(ts->input, ABS_Y, 0, 1023, 0, 0);
+
+	error = input_register_device(ts->input);
+	if (error) {
+		dev_err(&pdev->dev, "error registering touch input\n");
+		return error;
+	}
+
+	platform_set_drvdata(pdev, ts);
+
+	dev_info(&pdev->dev, "iPAQ micro touchscreen\n");
+
+	return 0;
+}
+
+static int micro_ts_suspend(struct device *dev)
+{
+	struct touchscreen_data *ts = dev_get_drvdata(dev);
+
+	micro_ts_toggle_receive(ts, false);
+
+	return 0;
+}
+
+static int micro_ts_resume(struct device *dev)
+{
+	struct touchscreen_data *ts = dev_get_drvdata(dev);
+	struct input_dev *input = ts->input;
+
+	guard(mutex)(&input->mutex);
+
+	if (input_device_enabled(input))
+		micro_ts_toggle_receive(ts, true);
+
+	return 0;
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(micro_ts_dev_pm_ops,
+				micro_ts_suspend, micro_ts_resume);
+
+static struct platform_driver micro_ts_device_driver = {
+	.driver	= {
+		.name	= "ipaq-micro-ts",
+		.pm	= pm_sleep_ptr(&micro_ts_dev_pm_ops),
+	},
+	.probe	= micro_ts_probe,
+};
+module_platform_driver(micro_ts_device_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("driver for iPAQ Atmel micro touchscreen");
+MODULE_ALIAS("platform:ipaq-micro-ts");