v4.19.13 snapshot.
diff --git a/drivers/i2c/busses/i2c-via.c b/drivers/i2c/busses/i2c-via.c
new file mode 100644
index 0000000..59b1d23
--- /dev/null
+++ b/drivers/i2c/busses/i2c-via.c
@@ -0,0 +1,163 @@
+/*
+ i2c Support for Via Technologies 82C586B South Bridge
+
+ Copyright (c) 1998, 1999 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/pci.h>
+#include <linux/ioport.h>
+#include <linux/i2c.h>
+#include <linux/i2c-algo-bit.h>
+#include <linux/io.h>
+
+/* Power management registers */
+#define PM_CFG_REVID 0x08 /* silicon revision code */
+#define PM_CFG_IOBASE0 0x20
+#define PM_CFG_IOBASE1 0x48
+
+#define I2C_DIR (pm_io_base+0x40)
+#define I2C_OUT (pm_io_base+0x42)
+#define I2C_IN (pm_io_base+0x44)
+#define I2C_SCL 0x02 /* clock bit in DIR/OUT/IN register */
+#define I2C_SDA 0x04
+
+/* io-region reservation */
+#define IOSPACE 0x06
+
+static struct pci_driver vt586b_driver;
+static u16 pm_io_base;
+
+/*
+ It does not appear from the datasheet that the GPIO pins are
+ open drain. So a we set a low value by setting the direction to
+ output and a high value by setting the direction to input and
+ relying on the required I2C pullup. The data value is initialized
+ to 0 in via_init() and never changed.
+*/
+static void bit_via_setscl(void *data, int state)
+{
+ outb(state ? inb(I2C_DIR) & ~I2C_SCL : inb(I2C_DIR) | I2C_SCL, I2C_DIR);
+}
+
+static void bit_via_setsda(void *data, int state)
+{
+ outb(state ? inb(I2C_DIR) & ~I2C_SDA : inb(I2C_DIR) | I2C_SDA, I2C_DIR);
+}
+
+static int bit_via_getscl(void *data)
+{
+ return (0 != (inb(I2C_IN) & I2C_SCL));
+}
+
+static int bit_via_getsda(void *data)
+{
+ return (0 != (inb(I2C_IN) & I2C_SDA));
+}
+
+
+static struct i2c_algo_bit_data bit_data = {
+ .setsda = bit_via_setsda,
+ .setscl = bit_via_setscl,
+ .getsda = bit_via_getsda,
+ .getscl = bit_via_getscl,
+ .udelay = 5,
+ .timeout = HZ
+};
+
+static struct i2c_adapter vt586b_adapter = {
+ .owner = THIS_MODULE,
+ .class = I2C_CLASS_HWMON | I2C_CLASS_SPD,
+ .name = "VIA i2c",
+ .algo_data = &bit_data,
+};
+
+
+static const struct pci_device_id vt586b_ids[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C586_3) },
+ { 0, }
+};
+
+MODULE_DEVICE_TABLE (pci, vt586b_ids);
+
+static int vt586b_probe(struct pci_dev *dev, const struct pci_device_id *id)
+{
+ u16 base;
+ u8 rev;
+ int res;
+
+ if (pm_io_base) {
+ dev_err(&dev->dev, "i2c-via: Will only support one host\n");
+ return -ENODEV;
+ }
+
+ pci_read_config_byte(dev, PM_CFG_REVID, &rev);
+
+ switch (rev) {
+ case 0x00:
+ base = PM_CFG_IOBASE0;
+ break;
+ case 0x01:
+ case 0x10:
+ base = PM_CFG_IOBASE1;
+ break;
+
+ default:
+ base = PM_CFG_IOBASE1;
+ /* later revision */
+ }
+
+ pci_read_config_word(dev, base, &pm_io_base);
+ pm_io_base &= (0xff << 8);
+
+ if (!request_region(I2C_DIR, IOSPACE, vt586b_driver.name)) {
+ dev_err(&dev->dev, "IO 0x%x-0x%x already in use\n", I2C_DIR, I2C_DIR + IOSPACE);
+ return -ENODEV;
+ }
+
+ outb(inb(I2C_DIR) & ~(I2C_SDA | I2C_SCL), I2C_DIR);
+ outb(inb(I2C_OUT) & ~(I2C_SDA | I2C_SCL), I2C_OUT);
+
+ /* set up the sysfs linkage to our parent device */
+ vt586b_adapter.dev.parent = &dev->dev;
+
+ res = i2c_bit_add_bus(&vt586b_adapter);
+ if ( res < 0 ) {
+ release_region(I2C_DIR, IOSPACE);
+ pm_io_base = 0;
+ return res;
+ }
+ return 0;
+}
+
+static void vt586b_remove(struct pci_dev *dev)
+{
+ i2c_del_adapter(&vt586b_adapter);
+ release_region(I2C_DIR, IOSPACE);
+ pm_io_base = 0;
+}
+
+
+static struct pci_driver vt586b_driver = {
+ .name = "vt586b_smbus",
+ .id_table = vt586b_ids,
+ .probe = vt586b_probe,
+ .remove = vt586b_remove,
+};
+
+module_pci_driver(vt586b_driver);
+
+MODULE_AUTHOR("Kyösti Mälkki <kmalkki@cc.hut.fi>");
+MODULE_DESCRIPTION("i2c for Via vt82c586b southbridge");
+MODULE_LICENSE("GPL");