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, 205 insertions, 0 deletions

diff --git a/drivers/input/joystick/magellan.c b/drivers/input/joystick/magellan.c
new file mode 100644
index 000000000..201a049c8
--- /dev/null
+++ b/drivers/input/joystick/magellan.c
@@ -0,0 +1,205 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  Copyright (c) 1999-2001 Vojtech Pavlik
+ */
+
+/*
+ * Magellan and Space Mouse 6dof controller driver for Linux
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/serio.h>
+
+#define DRIVER_DESC	"Magellan and SpaceMouse 6dof controller driver"
+
+MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+
+/*
+ * Definitions & global arrays.
+ */
+
+#define	MAGELLAN_MAX_LENGTH	32
+
+static int magellan_buttons[] = { BTN_0, BTN_1, BTN_2, BTN_3, BTN_4, BTN_5, BTN_6, BTN_7, BTN_8 };
+static int magellan_axes[] = { ABS_X, ABS_Y, ABS_Z, ABS_RX, ABS_RY, ABS_RZ };
+
+/*
+ * Per-Magellan data.
+ */
+
+struct magellan {
+	struct input_dev *dev;
+	int idx;
+	unsigned char data[MAGELLAN_MAX_LENGTH];
+	char phys[32];
+};
+
+/*
+ * magellan_crunch_nibbles() verifies that the bytes sent from the Magellan
+ * have correct upper nibbles for the lower ones, if not, the packet will
+ * be thrown away. It also strips these upper halves to simplify further
+ * processing.
+ */
+
+static int magellan_crunch_nibbles(unsigned char *data, int count)
+{
+	static const unsigned char nibbles[16] __nonstring = "0AB3D56GH9:K<MN?";
+
+	do {
+		if (data[count] == nibbles[data[count] & 0xf])
+			data[count] = data[count] & 0xf;
+		else
+			return -1;
+	} while (--count);
+
+	return 0;
+}
+
+static void magellan_process_packet(struct magellan* magellan)
+{
+	struct input_dev *dev = magellan->dev;
+	unsigned char *data = magellan->data;
+	int i, t;
+
+	if (!magellan->idx) return;
+
+	switch (magellan->data[0]) {
+
+		case 'd':				/* Axis data */
+			if (magellan->idx != 25) return;
+			if (magellan_crunch_nibbles(data, 24)) return;
+			for (i = 0; i < 6; i++)
+				input_report_abs(dev, magellan_axes[i],
+					(data[(i << 2) + 1] << 12 | data[(i << 2) + 2] << 8 |
+					 data[(i << 2) + 3] <<  4 | data[(i << 2) + 4]) - 32768);
+			break;
+
+		case 'k':				/* Button data */
+			if (magellan->idx != 4) return;
+			if (magellan_crunch_nibbles(data, 3)) return;
+			t = (data[1] << 1) | (data[2] << 5) | data[3];
+			for (i = 0; i < 9; i++) input_report_key(dev, magellan_buttons[i], (t >> i) & 1);
+			break;
+	}
+
+	input_sync(dev);
+}
+
+static irqreturn_t magellan_interrupt(struct serio *serio,
+		unsigned char data, unsigned int flags)
+{
+	struct magellan* magellan = serio_get_drvdata(serio);
+
+	if (data == '\r') {
+		magellan_process_packet(magellan);
+		magellan->idx = 0;
+	} else {
+		if (magellan->idx < MAGELLAN_MAX_LENGTH)
+			magellan->data[magellan->idx++] = data;
+	}
+	return IRQ_HANDLED;
+}
+
+/*
+ * magellan_disconnect() is the opposite of magellan_connect()
+ */
+
+static void magellan_disconnect(struct serio *serio)
+{
+	struct magellan* magellan = serio_get_drvdata(serio);
+
+	serio_close(serio);
+	serio_set_drvdata(serio, NULL);
+	input_unregister_device(magellan->dev);
+	kfree(magellan);
+}
+
+/*
+ * magellan_connect() is the routine that is called when someone adds a
+ * new serio device that supports Magellan protocol and registers it as
+ * an input device.
+ */
+
+static int magellan_connect(struct serio *serio, struct serio_driver *drv)
+{
+	struct magellan *magellan;
+	struct input_dev *input_dev;
+	int err = -ENOMEM;
+	int i;
+
+	magellan = kzalloc_obj(*magellan);
+	input_dev = input_allocate_device();
+	if (!magellan || !input_dev)
+		goto fail1;
+
+	magellan->dev = input_dev;
+	snprintf(magellan->phys, sizeof(magellan->phys), "%s/input0", serio->phys);
+
+	input_dev->name = "LogiCad3D Magellan / SpaceMouse";
+	input_dev->phys = magellan->phys;
+	input_dev->id.bustype = BUS_RS232;
+	input_dev->id.vendor = SERIO_MAGELLAN;
+	input_dev->id.product = 0x0001;
+	input_dev->id.version = 0x0100;
+	input_dev->dev.parent = &serio->dev;
+
+	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+
+	for (i = 0; i < 9; i++)
+		set_bit(magellan_buttons[i], input_dev->keybit);
+
+	for (i = 0; i < 6; i++)
+		input_set_abs_params(input_dev, magellan_axes[i], -360, 360, 0, 0);
+
+	serio_set_drvdata(serio, magellan);
+
+	err = serio_open(serio, drv);
+	if (err)
+		goto fail2;
+
+	err = input_register_device(magellan->dev);
+	if (err)
+		goto fail3;
+
+	return 0;
+
+ fail3:	serio_close(serio);
+ fail2:	serio_set_drvdata(serio, NULL);
+ fail1:	input_free_device(input_dev);
+	kfree(magellan);
+	return err;
+}
+
+/*
+ * The serio driver structure.
+ */
+
+static const struct serio_device_id magellan_serio_ids[] = {
+	{
+		.type	= SERIO_RS232,
+		.proto	= SERIO_MAGELLAN,
+		.id	= SERIO_ANY,
+		.extra	= SERIO_ANY,
+	},
+	{ 0 }
+};
+
+MODULE_DEVICE_TABLE(serio, magellan_serio_ids);
+
+static struct serio_driver magellan_drv = {
+	.driver		= {
+		.name	= "magellan",
+	},
+	.description	= DRIVER_DESC,
+	.id_table	= magellan_serio_ids,
+	.interrupt	= magellan_interrupt,
+	.connect	= magellan_connect,
+	.disconnect	= magellan_disconnect,
+};
+
+module_serio_driver(magellan_drv);