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, 217 insertions, 0 deletions

diff --git a/drivers/input/serio/pcips2.c b/drivers/input/serio/pcips2.c
new file mode 100644
index 000000000..78f47b0ca
--- /dev/null
+++ b/drivers/input/serio/pcips2.c
@@ -0,0 +1,217 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/drivers/input/serio/pcips2.c
+ *
+ *  Copyright (C) 2003 Russell King, All Rights Reserved.
+ *
+ *  I'm not sure if this is a generic PS/2 PCI interface or specific to
+ *  the Mobility Electronics docking station.
+ */
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/input.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+#include <linux/serio.h>
+#include <linux/delay.h>
+#include <asm/io.h>
+
+#define PS2_CTRL		(0)
+#define PS2_STATUS		(1)
+#define PS2_DATA		(2)
+
+#define PS2_CTRL_CLK		(1<<0)
+#define PS2_CTRL_DAT		(1<<1)
+#define PS2_CTRL_TXIRQ		(1<<2)
+#define PS2_CTRL_ENABLE		(1<<3)
+#define PS2_CTRL_RXIRQ		(1<<4)
+
+#define PS2_STAT_CLK		(1<<0)
+#define PS2_STAT_DAT		(1<<1)
+#define PS2_STAT_PARITY		(1<<2)
+#define PS2_STAT_RXFULL		(1<<5)
+#define PS2_STAT_TXBUSY		(1<<6)
+#define PS2_STAT_TXEMPTY	(1<<7)
+
+struct pcips2_data {
+	struct serio	*io;
+	unsigned int	base;
+	struct pci_dev	*dev;
+};
+
+static int pcips2_write(struct serio *io, unsigned char val)
+{
+	struct pcips2_data *ps2if = io->port_data;
+	unsigned int stat;
+
+	do {
+		stat = inb(ps2if->base + PS2_STATUS);
+		cpu_relax();
+	} while (!(stat & PS2_STAT_TXEMPTY));
+
+	outb(val, ps2if->base + PS2_DATA);
+
+	return 0;
+}
+
+static irqreturn_t pcips2_interrupt(int irq, void *devid)
+{
+	struct pcips2_data *ps2if = devid;
+	unsigned char status, scancode;
+	int handled = 0;
+
+	do {
+		unsigned int flag;
+
+		status = inb(ps2if->base + PS2_STATUS);
+		if (!(status & PS2_STAT_RXFULL))
+			break;
+		handled = 1;
+		scancode = inb(ps2if->base + PS2_DATA);
+		if (status == 0xff && scancode == 0xff)
+			break;
+
+		flag = (status & PS2_STAT_PARITY) ? 0 : SERIO_PARITY;
+
+		if (hweight8(scancode) & 1)
+			flag ^= SERIO_PARITY;
+
+		serio_interrupt(ps2if->io, scancode, flag);
+	} while (1);
+	return IRQ_RETVAL(handled);
+}
+
+static void pcips2_flush_input(struct pcips2_data *ps2if)
+{
+	unsigned char status, scancode;
+
+	do {
+		status = inb(ps2if->base + PS2_STATUS);
+		if (!(status & PS2_STAT_RXFULL))
+			break;
+		scancode = inb(ps2if->base + PS2_DATA);
+		if (status == 0xff && scancode == 0xff)
+			break;
+	} while (1);
+}
+
+static int pcips2_open(struct serio *io)
+{
+	struct pcips2_data *ps2if = io->port_data;
+	int ret, val = 0;
+
+	outb(PS2_CTRL_ENABLE, ps2if->base);
+	pcips2_flush_input(ps2if);
+
+	ret = request_irq(ps2if->dev->irq, pcips2_interrupt, IRQF_SHARED,
+			  "pcips2", ps2if);
+	if (ret == 0)
+		val = PS2_CTRL_ENABLE | PS2_CTRL_RXIRQ;
+
+	outb(val, ps2if->base);
+
+	return ret;
+}
+
+static void pcips2_close(struct serio *io)
+{
+	struct pcips2_data *ps2if = io->port_data;
+
+	outb(0, ps2if->base);
+
+	free_irq(ps2if->dev->irq, ps2if);
+}
+
+static int pcips2_probe(struct pci_dev *dev, const struct pci_device_id *id)
+{
+	struct pcips2_data *ps2if;
+	struct serio *serio;
+	int ret;
+
+	ret = pci_enable_device(dev);
+	if (ret)
+		goto out;
+
+	ret = pci_request_regions(dev, "pcips2");
+	if (ret)
+		goto disable;
+
+	ps2if = kzalloc_obj(*ps2if);
+	serio = kzalloc_obj(*serio);
+	if (!ps2if || !serio) {
+		ret = -ENOMEM;
+		goto release;
+	}
+
+
+	serio->id.type		= SERIO_8042;
+	serio->write		= pcips2_write;
+	serio->open		= pcips2_open;
+	serio->close		= pcips2_close;
+	strscpy(serio->name, pci_name(dev), sizeof(serio->name));
+	strscpy(serio->phys, dev_name(&dev->dev), sizeof(serio->phys));
+	serio->port_data	= ps2if;
+	serio->dev.parent	= &dev->dev;
+	ps2if->io		= serio;
+	ps2if->dev		= dev;
+	ps2if->base		= pci_resource_start(dev, 0);
+
+	pci_set_drvdata(dev, ps2if);
+
+	serio_register_port(ps2if->io);
+	return 0;
+
+ release:
+	kfree(ps2if);
+	kfree(serio);
+	pci_release_regions(dev);
+ disable:
+	pci_disable_device(dev);
+ out:
+	return ret;
+}
+
+static void pcips2_remove(struct pci_dev *dev)
+{
+	struct pcips2_data *ps2if = pci_get_drvdata(dev);
+
+	serio_unregister_port(ps2if->io);
+	kfree(ps2if);
+	pci_release_regions(dev);
+	pci_disable_device(dev);
+}
+
+static const struct pci_device_id pcips2_ids[] = {
+	{
+		.vendor		= 0x14f2,	/* MOBILITY */
+		.device		= 0x0123,	/* Keyboard */
+		.subvendor	= PCI_ANY_ID,
+		.subdevice	= PCI_ANY_ID,
+		.class		= PCI_CLASS_INPUT_KEYBOARD << 8,
+		.class_mask	= 0xffff00,
+	},
+	{
+		.vendor		= 0x14f2,	/* MOBILITY */
+		.device		= 0x0124,	/* Mouse */
+		.subvendor	= PCI_ANY_ID,
+		.subdevice	= PCI_ANY_ID,
+		.class		= PCI_CLASS_INPUT_MOUSE << 8,
+		.class_mask	= 0xffff00,
+	},
+	{ 0, }
+};
+MODULE_DEVICE_TABLE(pci, pcips2_ids);
+
+static struct pci_driver pcips2_driver = {
+	.name			= "pcips2",
+	.id_table		= pcips2_ids,
+	.probe			= pcips2_probe,
+	.remove			= pcips2_remove,
+};
+
+module_pci_driver(pcips2_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
+MODULE_DESCRIPTION("PCI PS/2 keyboard/mouse driver");