Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 275 insertions, 0 deletions

diff --git a/drivers/i2c/busses/i2c-parport-light.c b/drivers/i2c/busses/i2c-parport-light.c
new file mode 100644
index 000000000..fa41ff799
--- /dev/null
+++ b/drivers/i2c/busses/i2c-parport-light.c
@@ -0,0 +1,275 @@
+/* ------------------------------------------------------------------------ *
+ * i2c-parport-light.c I2C bus over parallel port                           *
+ * ------------------------------------------------------------------------ *
+   Copyright (C) 2003-2010 Jean Delvare <jdelvare@suse.de>
+
+   Based on older i2c-velleman.c driver
+   Copyright (C) 1995-2000 Simon G. Vogl
+   With some changes from:
+   Frodo Looijaard <frodol@dds.nl>
+   Kyösti Mälkki <kmalkki@cc.hut.fi>
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+ * ------------------------------------------------------------------------ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/ioport.h>
+#include <linux/i2c.h>
+#include <linux/i2c-algo-bit.h>
+#include <linux/i2c-smbus.h>
+#include <linux/io.h>
+#include "i2c-parport.h"
+
+#define DEFAULT_BASE 0x378
+#define DRVNAME "i2c-parport-light"
+
+static struct platform_device *pdev;
+
+static u16 base;
+module_param_hw(base, ushort, ioport, 0);
+MODULE_PARM_DESC(base, "Base I/O address");
+
+static int irq;
+module_param_hw(irq, int, irq, 0);
+MODULE_PARM_DESC(irq, "IRQ (optional)");
+
+/* ----- Low-level parallel port access ----------------------------------- */
+
+static inline void port_write(unsigned char p, unsigned char d)
+{
+	outb(d, base+p);
+}
+
+static inline unsigned char port_read(unsigned char p)
+{
+	return inb(base+p);
+}
+
+/* ----- Unified line operation functions --------------------------------- */
+
+static inline void line_set(int state, const struct lineop *op)
+{
+	u8 oldval = port_read(op->port);
+
+	/* Touch only the bit(s) needed */
+	if ((op->inverted && !state) || (!op->inverted && state))
+		port_write(op->port, oldval | op->val);
+	else
+		port_write(op->port, oldval & ~op->val);
+}
+
+static inline int line_get(const struct lineop *op)
+{
+	u8 oldval = port_read(op->port);
+
+	return ((op->inverted && (oldval & op->val) != op->val)
+	    || (!op->inverted && (oldval & op->val) == op->val));
+}
+
+/* ----- I2C algorithm call-back functions and structures ----------------- */
+
+static void parport_setscl(void *data, int state)
+{
+	line_set(state, &adapter_parm[type].setscl);
+}
+
+static void parport_setsda(void *data, int state)
+{
+	line_set(state, &adapter_parm[type].setsda);
+}
+
+static int parport_getscl(void *data)
+{
+	return line_get(&adapter_parm[type].getscl);
+}
+
+static int parport_getsda(void *data)
+{
+	return line_get(&adapter_parm[type].getsda);
+}
+
+/* Encapsulate the functions above in the correct structure
+   Note that getscl will be set to NULL by the attaching code for adapters
+   that cannot read SCL back */
+static struct i2c_algo_bit_data parport_algo_data = {
+	.setsda		= parport_setsda,
+	.setscl		= parport_setscl,
+	.getsda		= parport_getsda,
+	.getscl		= parport_getscl,
+	.udelay		= 50,
+	.timeout	= HZ,
+};
+
+/* ----- Driver registration ---------------------------------------------- */
+
+static struct i2c_adapter parport_adapter = {
+	.owner		= THIS_MODULE,
+	.class		= I2C_CLASS_HWMON,
+	.algo_data	= &parport_algo_data,
+	.name		= "Parallel port adapter (light)",
+};
+
+/* SMBus alert support */
+static struct i2c_smbus_alert_setup alert_data = {
+};
+static struct i2c_client *ara;
+static struct lineop parport_ctrl_irq = {
+	.val		= (1 << 4),
+	.port		= PORT_CTRL,
+};
+
+static int i2c_parport_probe(struct platform_device *pdev)
+{
+	int err;
+
+	/* Reset hardware to a sane state (SCL and SDA high) */
+	parport_setsda(NULL, 1);
+	parport_setscl(NULL, 1);
+	/* Other init if needed (power on...) */
+	if (adapter_parm[type].init.val) {
+		line_set(1, &adapter_parm[type].init);
+		/* Give powered devices some time to settle */
+		msleep(100);
+	}
+
+	parport_adapter.dev.parent = &pdev->dev;
+	err = i2c_bit_add_bus(&parport_adapter);
+	if (err) {
+		dev_err(&pdev->dev, "Unable to register with I2C\n");
+		return err;
+	}
+
+	/* Setup SMBus alert if supported */
+	if (adapter_parm[type].smbus_alert && irq) {
+		alert_data.irq = irq;
+		ara = i2c_setup_smbus_alert(&parport_adapter, &alert_data);
+		if (ara)
+			line_set(1, &parport_ctrl_irq);
+		else
+			dev_warn(&pdev->dev, "Failed to register ARA client\n");
+	}
+
+	return 0;
+}
+
+static int i2c_parport_remove(struct platform_device *pdev)
+{
+	if (ara) {
+		line_set(0, &parport_ctrl_irq);
+		i2c_unregister_device(ara);
+		ara = NULL;
+	}
+	i2c_del_adapter(&parport_adapter);
+
+	/* Un-init if needed (power off...) */
+	if (adapter_parm[type].init.val)
+		line_set(0, &adapter_parm[type].init);
+
+	return 0;
+}
+
+static struct platform_driver i2c_parport_driver = {
+	.driver = {
+		.name	= DRVNAME,
+	},
+	.probe		= i2c_parport_probe,
+	.remove		= i2c_parport_remove,
+};
+
+static int __init i2c_parport_device_add(u16 address)
+{
+	int err;
+
+	pdev = platform_device_alloc(DRVNAME, -1);
+	if (!pdev) {
+		err = -ENOMEM;
+		printk(KERN_ERR DRVNAME ": Device allocation failed\n");
+		goto exit;
+	}
+
+	err = platform_device_add(pdev);
+	if (err) {
+		printk(KERN_ERR DRVNAME ": Device addition failed (%d)\n",
+		       err);
+		goto exit_device_put;
+	}
+
+	return 0;
+
+exit_device_put:
+	platform_device_put(pdev);
+exit:
+	return err;
+}
+
+static int __init i2c_parport_init(void)
+{
+	int err;
+
+	if (type < 0) {
+		printk(KERN_ERR DRVNAME ": adapter type unspecified\n");
+		return -ENODEV;
+	}
+
+	if (type >= ARRAY_SIZE(adapter_parm)) {
+		printk(KERN_ERR DRVNAME ": invalid type (%d)\n", type);
+		return -ENODEV;
+	}
+
+	if (base == 0) {
+		pr_info(DRVNAME ": using default base 0x%x\n", DEFAULT_BASE);
+		base = DEFAULT_BASE;
+	}
+
+	if (!request_region(base, 3, DRVNAME))
+		return -EBUSY;
+
+	if (irq != 0)
+		pr_info(DRVNAME ": using irq %d\n", irq);
+
+	if (!adapter_parm[type].getscl.val)
+		parport_algo_data.getscl = NULL;
+
+	/* Sets global pdev as a side effect */
+	err = i2c_parport_device_add(base);
+	if (err)
+		goto exit_release;
+
+	err = platform_driver_register(&i2c_parport_driver);
+	if (err)
+		goto exit_device;
+
+	return 0;
+
+exit_device:
+	platform_device_unregister(pdev);
+exit_release:
+	release_region(base, 3);
+	return err;
+}
+
+static void __exit i2c_parport_exit(void)
+{
+	platform_driver_unregister(&i2c_parport_driver);
+	platform_device_unregister(pdev);
+	release_region(base, 3);
+}
+
+MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
+MODULE_DESCRIPTION("I2C bus over parallel port (light)");
+MODULE_LICENSE("GPL");
+
+module_init(i2c_parport_init);
+module_exit(i2c_parport_exit);