[PATCH] I2C: add the i2c-voodoo3 i2c bus driver

This is based on the lmsensor cvs version of the driver, but is cleaned
it up and ported it to 2.6.

drivers/i2c/busses/Kconfig

@@ -189,4 +189,15 @@ config I2C_VIAPRO
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-viapro.
 
+config I2C_VOODOO3
+	tristate "Voodoo 3"
+	depends on I2C && PCI && EXPERIMENTAL
+	help
+
+	  If you say yes to this option, support will be included for the
+	  Voodoo 3 I2C interface.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called i2c-voodoo3.
+
 endmenu

drivers/i2c/busses/Makefile

@@ -17,3 +17,4 @@ obj-$(CONFIG_I2C_SIS630)	+= i2c-sis630.o
 obj-$(CONFIG_I2C_SIS96X)	+= i2c-sis96x.o
 obj-$(CONFIG_I2C_VIA)		+= i2c-via.o
 obj-$(CONFIG_I2C_VIAPRO)	+= i2c-viapro.o
+obj-$(CONFIG_I2C_VOODOO3)	+= i2c-voodoo3.o

drivers/i2c/busses/i2c-voodoo3.c

+/*
+    voodoo3.c - Part of lm_sensors, Linux kernel modules for hardware
+              monitoring
+    Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl>,
+    Philip Edelbrock <phil@netroedge.com>,
+    Ralph Metzler <rjkm@thp.uni-koeln.de>, and
+    Mark D. Studebaker <mdsxyz123@yahoo.com>
+    
+    Based on code written by Ralph Metzler <rjkm@thp.uni-koeln.de> and
+    Simon Vogl
+
+    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.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+/* This interfaces to the I2C bus of the Voodoo3 to gain access to
+    the BT869 and possibly other I2C devices. */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/i2c.h>
+#include <linux/i2c-algo-bit.h>
+
+/* the only registers we use */
+#define REG		0x78
+#define REG2 		0x70
+
+/* bit locations in the register */
+#define DDC_ENAB	0x00040000
+#define DDC_SCL_OUT	0x00080000
+#define DDC_SDA_OUT	0x00100000
+#define DDC_SCL_IN	0x00200000
+#define DDC_SDA_IN	0x00400000
+#define I2C_ENAB	0x00800000
+#define I2C_SCL_OUT	0x01000000
+#define I2C_SDA_OUT	0x02000000
+#define I2C_SCL_IN	0x04000000
+#define I2C_SDA_IN	0x08000000
+
+/* initialization states */
+#define INIT2		0x2
+#define INIT3		0x4
+
+/* delays */
+#define CYCLE_DELAY	10
+#define TIMEOUT		(HZ / 2)
+
+
+static void *ioaddr;
+
+/* The voo GPIO registers don't have individual masks for each bit
+   so we always have to read before writing. */
+
+static void bit_vooi2c_setscl(void *data, int val)
+{
+	unsigned int r;
+	r = readl(ioaddr + REG);
+	if (val)
+		r |= I2C_SCL_OUT;
+	else
+		r &= ~I2C_SCL_OUT;
+	writel(r, ioaddr + REG);
+	readl(ioaddr + REG);	/* flush posted write */
+}
+
+static void bit_vooi2c_setsda(void *data, int val)
+{
+	unsigned int r;
+	r = readl(ioaddr + REG);
+	if (val)
+		r |= I2C_SDA_OUT;
+	else
+		r &= ~I2C_SDA_OUT;
+	writel(r, ioaddr + REG);
+	readl(ioaddr + REG);	/* flush posted write */
+}
+
+/* The GPIO pins are open drain, so the pins always remain outputs.
+   We rely on the i2c-algo-bit routines to set the pins high before
+   reading the input from other chips. */
+
+static int bit_vooi2c_getscl(void *data)
+{
+	return (0 != (readl(ioaddr + REG) & I2C_SCL_IN));
+}
+
+static int bit_vooi2c_getsda(void *data)
+{
+	return (0 != (readl(ioaddr + REG) & I2C_SDA_IN));
+}
+
+static void bit_vooddc_setscl(void *data, int val)
+{
+	unsigned int r;
+	r = readl(ioaddr + REG);
+	if (val)
+		r |= DDC_SCL_OUT;
+	else
+		r &= ~DDC_SCL_OUT;
+	writel(r, ioaddr + REG);
+	readl(ioaddr + REG);	/* flush posted write */
+}
+
+static void bit_vooddc_setsda(void *data, int val)
+{
+	unsigned int r;
+	r = readl(ioaddr + REG);
+	if (val)
+		r |= DDC_SDA_OUT;
+	else
+		r &= ~DDC_SDA_OUT;
+	writel(r, ioaddr + REG);
+	readl(ioaddr + REG);	/* flush posted write */
+}
+
+static int bit_vooddc_getscl(void *data)
+{
+	return (0 != (readl(ioaddr + REG) & DDC_SCL_IN));
+}
+
+static int bit_vooddc_getsda(void *data)
+{
+	return (0 != (readl(ioaddr + REG) & DDC_SDA_IN));
+}
+
+static int config_v3(struct pci_dev *dev)
+{
+	unsigned int cadr;
+
+	/* map Voodoo3 memory */
+	cadr = dev->resource[0].start;
+	cadr &= PCI_BASE_ADDRESS_MEM_MASK;
+	ioaddr = ioremap_nocache(cadr, 0x1000);
+	if (ioaddr) {
+		writel(0x8160, ioaddr + REG2);
+		writel(0xcffc0020, ioaddr + REG);
+		dev_info(&dev->dev, "Using Banshee/Voodoo3 I2C device at %p\n", ioaddr);
+		return 0;
+	}
+	return -ENODEV;
+}
+
+static struct i2c_algo_bit_data voo_i2c_bit_data = {
+	.setsda		= bit_vooi2c_setsda,
+	.setscl		= bit_vooi2c_setscl,
+	.getsda		= bit_vooi2c_getsda,
+	.getscl		= bit_vooi2c_getscl,
+	.udelay		= CYCLE_DELAY,
+	.mdelay		= CYCLE_DELAY,
+	.timeout	= TIMEOUT
+};
+
+static struct i2c_adapter voodoo3_i2c_adapter = {
+	.owner		= THIS_MODULE,
+	.name		= "I2C Voodoo3/Banshee adapter",
+	.algo_data	= &voo_i2c_bit_data,
+};
+
+static struct i2c_algo_bit_data voo_ddc_bit_data = {
+	.setsda		= bit_vooddc_setsda,
+	.setscl		= bit_vooddc_setscl,
+	.getsda		= bit_vooddc_getsda,
+	.getscl		= bit_vooddc_getscl,
+	.udelay		= CYCLE_DELAY,
+	.mdelay		= CYCLE_DELAY,
+	.timeout	= TIMEOUT
+};
+
+static struct i2c_adapter voodoo3_ddc_adapter = {
+	.owner		= THIS_MODULE,
+	.name		= "DDC Voodoo3/Banshee adapter",
+	.algo_data	= &voo_ddc_bit_data,
+};
+
+static struct pci_device_id voodoo3_ids[] __devinitdata = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_3DFX, PCI_DEVICE_ID_3DFX_VOODOO3) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_3DFX, PCI_DEVICE_ID_3DFX_BANSHEE) },
+	{ 0, }
+};
+
+static int __devinit voodoo3_probe(struct pci_dev *dev, const struct pci_device_id *id)
+{
+	int retval;
+
+	retval = config_v3(dev);
+	if (retval)
+		return retval;
+
+	/* set up the sysfs linkage to our parent device */
+	voodoo3_i2c_adapter.dev.parent = &dev->dev;
+	voodoo3_ddc_adapter.dev.parent = &dev->dev;
+
+	retval = i2c_bit_add_bus(&voodoo3_i2c_adapter);
+	if (retval)
+		return retval;
+	retval = i2c_bit_add_bus(&voodoo3_ddc_adapter);
+	if (retval)
+		i2c_bit_del_bus(&voodoo3_i2c_adapter);
+	return retval;
+}
+
+static void __devexit voodoo3_remove(struct pci_dev *dev)
+{
+	i2c_bit_del_bus(&voodoo3_i2c_adapter);
+ 	i2c_bit_del_bus(&voodoo3_ddc_adapter);
+	iounmap(ioaddr);
+}
+
+static struct pci_driver voodoo3_driver = {
+	.name		= "voodoo3 smbus",
+	.id_table	= voodoo3_ids,
+	.probe		= voodoo3_probe,
+	.remove		= __devexit_p(voodoo3_remove),
+};
+
+static int __init i2c_voodoo3_init(void)
+{
+	return pci_module_init(&voodoo3_driver);
+}
+
+static void __exit i2c_voodoo3_exit(void)
+{
+	pci_unregister_driver(&voodoo3_driver);
+}
+
+
+MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>, "
+		"Philip Edelbrock <phil@netroedge.com>, "
+		"Ralph Metzler <rjkm@thp.uni-koeln.de>, "
+		"and Mark D. Studebaker <mdsxyz123@yahoo.com>");
+MODULE_DESCRIPTION("Voodoo3 I2C/SMBus driver");
+MODULE_LICENSE("GPL");
+
+module_init(i2c_voodoo3_init);
+module_exit(i2c_voodoo3_exit);