diff --git a/arch/powerpc/platforms/powermac/pmac_low_i2c.c b/arch/powerpc/platforms/powermac/pmac_low_i2c.c
new file mode 100644
index 0000000..f3f39e8
--- /dev/null
+++ b/arch/powerpc/platforms/powermac/pmac_low_i2c.c
@@ -0,0 +1,523 @@
+/*
+ *  arch/ppc/platforms/pmac_low_i2c.c
+ *
+ *  Copyright (C) 2003 Ben. Herrenschmidt (benh@kernel.crashing.org)
+ *
+ *  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 file contains some low-level i2c access routines that
+ *  need to be used by various bits of the PowerMac platform code
+ *  at times where the real asynchronous & interrupt driven driver
+ *  cannot be used. The API borrows some semantics from the darwin
+ *  driver in order to ease the implementation of the platform
+ *  properties parser
+ */
+
+#undef DEBUG
+
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/adb.h>
+#include <linux/pmu.h>
+#include <asm/keylargo.h>
+#include <asm/uninorth.h>
+#include <asm/io.h>
+#include <asm/prom.h>
+#include <asm/machdep.h>
+#include <asm/pmac_low_i2c.h>
+
+#define MAX_LOW_I2C_HOST	4
+
+#ifdef DEBUG
+#define DBG(x...) do {\
+		printk(KERN_DEBUG "KW:" x);	\
+	} while(0)
+#else
+#define DBG(x...)
+#endif
+
+struct low_i2c_host;
+
+typedef int (*low_i2c_func_t)(struct low_i2c_host *host, u8 addr, u8 sub, u8 *data, int len);
+
+struct low_i2c_host
+{
+	struct device_node	*np;		/* OF device node */
+	struct semaphore	mutex;		/* Access mutex for use by i2c-keywest */
+	low_i2c_func_t		func;		/* Access function */
+	unsigned int		is_open : 1;	/* Poor man's access control */
+	int			mode;		/* Current mode */
+	int			channel;	/* Current channel */
+	int			num_channels;	/* Number of channels */
+	void __iomem		*base;		/* For keywest-i2c, base address */
+	int			bsteps;		/* And register stepping */
+	int			speed;		/* And speed */
+};
+
+static struct low_i2c_host	low_i2c_hosts[MAX_LOW_I2C_HOST];
+
+/* No locking is necessary on allocation, we are running way before
+ * anything can race with us
+ */
+static struct low_i2c_host *find_low_i2c_host(struct device_node *np)
+{
+	int i;
+
+	for (i = 0; i < MAX_LOW_I2C_HOST; i++)
+		if (low_i2c_hosts[i].np == np)
+			return &low_i2c_hosts[i];
+	return NULL;
+}
+
+/*
+ *
+ * i2c-keywest implementation (UniNorth, U2, U3, Keylargo's)
+ *
+ */
+
+/*
+ * Keywest i2c definitions borrowed from drivers/i2c/i2c-keywest.h,
+ * should be moved somewhere in include/asm-ppc/
+ */
+/* Register indices */
+typedef enum {
+	reg_mode = 0,
+	reg_control,
+	reg_status,
+	reg_isr,
+	reg_ier,
+	reg_addr,
+	reg_subaddr,
+	reg_data
+} reg_t;
+
+
+/* Mode register */
+#define KW_I2C_MODE_100KHZ	0x00
+#define KW_I2C_MODE_50KHZ	0x01
+#define KW_I2C_MODE_25KHZ	0x02
+#define KW_I2C_MODE_DUMB	0x00
+#define KW_I2C_MODE_STANDARD	0x04
+#define KW_I2C_MODE_STANDARDSUB	0x08
+#define KW_I2C_MODE_COMBINED	0x0C
+#define KW_I2C_MODE_MODE_MASK	0x0C
+#define KW_I2C_MODE_CHAN_MASK	0xF0
+
+/* Control register */
+#define KW_I2C_CTL_AAK		0x01
+#define KW_I2C_CTL_XADDR	0x02
+#define KW_I2C_CTL_STOP		0x04
+#define KW_I2C_CTL_START	0x08
+
+/* Status register */
+#define KW_I2C_STAT_BUSY	0x01
+#define KW_I2C_STAT_LAST_AAK	0x02
+#define KW_I2C_STAT_LAST_RW	0x04
+#define KW_I2C_STAT_SDA		0x08
+#define KW_I2C_STAT_SCL		0x10
+
+/* IER & ISR registers */
+#define KW_I2C_IRQ_DATA		0x01
+#define KW_I2C_IRQ_ADDR		0x02
+#define KW_I2C_IRQ_STOP		0x04
+#define KW_I2C_IRQ_START	0x08
+#define KW_I2C_IRQ_MASK		0x0F
+
+/* State machine states */
+enum {
+	state_idle,
+	state_addr,
+	state_read,
+	state_write,
+	state_stop,
+	state_dead
+};
+
+#define WRONG_STATE(name) do {\
+		printk(KERN_DEBUG "KW: wrong state. Got %s, state: %s (isr: %02x)\n", \
+		       name, __kw_state_names[state], isr); \
+	} while(0)
+
+static const char *__kw_state_names[] = {
+	"state_idle",
+	"state_addr",
+	"state_read",
+	"state_write",
+	"state_stop",
+	"state_dead"
+};
+
+static inline u8 __kw_read_reg(struct low_i2c_host *host, reg_t reg)
+{
+	return readb(host->base + (((unsigned int)reg) << host->bsteps));
+}
+
+static inline void __kw_write_reg(struct low_i2c_host *host, reg_t reg, u8 val)
+{
+	writeb(val, host->base + (((unsigned)reg) << host->bsteps));
+	(void)__kw_read_reg(host, reg_subaddr);
+}
+
+#define kw_write_reg(reg, val)	__kw_write_reg(host, reg, val) 
+#define kw_read_reg(reg)	__kw_read_reg(host, reg) 
+
+
+/* Don't schedule, the g5 fan controller is too
+ * timing sensitive
+ */
+static u8 kw_wait_interrupt(struct low_i2c_host* host)
+{
+	int i, j;
+	u8 isr;
+	
+	for (i = 0; i < 100000; i++) {
+		isr = kw_read_reg(reg_isr) & KW_I2C_IRQ_MASK;
+		if (isr != 0)
+			return isr;
+
+		/* This code is used with the timebase frozen, we cannot rely
+		 * on udelay ! For now, just use a bogus loop
+		 */
+		for (j = 1; j < 10000; j++)
+			mb();
+	}
+	return isr;
+}
+
+static int kw_handle_interrupt(struct low_i2c_host *host, int state, int rw, int *rc, u8 **data, int *len, u8 isr)
+{
+	u8 ack;
+
+	DBG("kw_handle_interrupt(%s, isr: %x)\n", __kw_state_names[state], isr);
+
+	if (isr == 0) {
+		if (state != state_stop) {
+			DBG("KW: Timeout !\n");
+			*rc = -EIO;
+			goto stop;
+		}
+		if (state == state_stop) {
+			ack = kw_read_reg(reg_status);
+			if (!(ack & KW_I2C_STAT_BUSY)) {
+				state = state_idle;
+				kw_write_reg(reg_ier, 0x00);
+			}
+		}
+		return state;
+	}
+
+	if (isr & KW_I2C_IRQ_ADDR) {
+		ack = kw_read_reg(reg_status);
+		if (state != state_addr) {
+			kw_write_reg(reg_isr, KW_I2C_IRQ_ADDR);
+			WRONG_STATE("KW_I2C_IRQ_ADDR"); 
+			*rc = -EIO;
+			goto stop;
+		}
+		if ((ack & KW_I2C_STAT_LAST_AAK) == 0) {			
+			*rc = -ENODEV;
+			DBG("KW: NAK on address\n");
+			return state_stop;		     
+		} else {
+			if (rw) {
+				state = state_read;
+				if (*len > 1)
+					kw_write_reg(reg_control, KW_I2C_CTL_AAK);
+			} else {
+				state = state_write;
+				kw_write_reg(reg_data, **data);
+				(*data)++; (*len)--;
+			}
+		}
+		kw_write_reg(reg_isr, KW_I2C_IRQ_ADDR);
+	}
+
+	if (isr & KW_I2C_IRQ_DATA) {
+		if (state == state_read) {
+			**data = kw_read_reg(reg_data);
+			(*data)++; (*len)--;
+			kw_write_reg(reg_isr, KW_I2C_IRQ_DATA);
+			if ((*len) == 0)
+				state = state_stop;
+			else if ((*len) == 1)
+				kw_write_reg(reg_control, 0);
+		} else if (state == state_write) {
+			ack = kw_read_reg(reg_status);
+			if ((ack & KW_I2C_STAT_LAST_AAK) == 0) {
+				DBG("KW: nack on data write\n");
+				*rc = -EIO;
+				goto stop;
+			} else if (*len) {
+				kw_write_reg(reg_data, **data);
+				(*data)++; (*len)--;
+			} else {
+				kw_write_reg(reg_control, KW_I2C_CTL_STOP);
+				state = state_stop;
+				*rc = 0;
+			}
+			kw_write_reg(reg_isr, KW_I2C_IRQ_DATA);
+		} else {
+			kw_write_reg(reg_isr, KW_I2C_IRQ_DATA);
+			WRONG_STATE("KW_I2C_IRQ_DATA"); 
+			if (state != state_stop) {
+				*rc = -EIO;
+				goto stop;
+			}
+		}
+	}
+
+	if (isr & KW_I2C_IRQ_STOP) {
+		kw_write_reg(reg_isr, KW_I2C_IRQ_STOP);
+		if (state != state_stop) {
+			WRONG_STATE("KW_I2C_IRQ_STOP");
+			*rc = -EIO;
+		}
+		return state_idle;
+	}
+
+	if (isr & KW_I2C_IRQ_START)
+		kw_write_reg(reg_isr, KW_I2C_IRQ_START);
+
+	return state;
+
+ stop:
+	kw_write_reg(reg_control, KW_I2C_CTL_STOP);	
+	return state_stop;
+}
+
+static int keywest_low_i2c_func(struct low_i2c_host *host, u8 addr, u8 subaddr, u8 *data, int len)
+{
+	u8 mode_reg = host->speed;
+	int state = state_addr;
+	int rc = 0;
+
+	/* Setup mode & subaddress if any */
+	switch(host->mode) {
+	case pmac_low_i2c_mode_dumb:
+		printk(KERN_ERR "low_i2c: Dumb mode not supported !\n");
+		return -EINVAL;
+	case pmac_low_i2c_mode_std:
+		mode_reg |= KW_I2C_MODE_STANDARD;
+		break;
+	case pmac_low_i2c_mode_stdsub:
+		mode_reg |= KW_I2C_MODE_STANDARDSUB;
+		break;
+	case pmac_low_i2c_mode_combined:
+		mode_reg |= KW_I2C_MODE_COMBINED;
+		break;
+	}
+
+	/* Setup channel & clear pending irqs */
+	kw_write_reg(reg_isr, kw_read_reg(reg_isr));
+	kw_write_reg(reg_mode, mode_reg | (host->channel << 4));
+	kw_write_reg(reg_status, 0);
+
+	/* Set up address and r/w bit */
+	kw_write_reg(reg_addr, addr);
+
+	/* Set up the sub address */
+	if ((mode_reg & KW_I2C_MODE_MODE_MASK) == KW_I2C_MODE_STANDARDSUB
+	    || (mode_reg & KW_I2C_MODE_MODE_MASK) == KW_I2C_MODE_COMBINED)
+		kw_write_reg(reg_subaddr, subaddr);
+
+	/* Start sending address & disable interrupt*/
+	kw_write_reg(reg_ier, 0 /*KW_I2C_IRQ_MASK*/);
+	kw_write_reg(reg_control, KW_I2C_CTL_XADDR);
+
+	/* State machine, to turn into an interrupt handler */
+	while(state != state_idle) {
+		u8 isr = kw_wait_interrupt(host);
+		state = kw_handle_interrupt(host, state, addr & 1, &rc, &data, &len, isr);
+	}
+
+	return rc;
+}
+
+static void keywest_low_i2c_add(struct device_node *np)
+{
+	struct low_i2c_host	*host = find_low_i2c_host(NULL);
+	u32			*psteps, *prate, steps, aoffset = 0;
+	struct device_node	*parent;
+
+	if (host == NULL) {
+		printk(KERN_ERR "low_i2c: Can't allocate host for %s\n",
+		       np->full_name);
+		return;
+	}
+	memset(host, 0, sizeof(*host));
+
+	init_MUTEX(&host->mutex);
+	host->np = of_node_get(np);	
+	psteps = (u32 *)get_property(np, "AAPL,address-step", NULL);
+	steps = psteps ? (*psteps) : 0x10;
+	for (host->bsteps = 0; (steps & 0x01) == 0; host->bsteps++)
+		steps >>= 1;
+	parent = of_get_parent(np);
+	host->num_channels = 1;
+	if (parent && parent->name[0] == 'u') {
+		host->num_channels = 2;
+		aoffset = 3;
+	}
+	/* Select interface rate */
+	host->speed = KW_I2C_MODE_100KHZ;
+	prate = (u32 *)get_property(np, "AAPL,i2c-rate", NULL);
+	if (prate) switch(*prate) {
+	case 100:
+		host->speed = KW_I2C_MODE_100KHZ;
+		break;
+	case 50:
+		host->speed = KW_I2C_MODE_50KHZ;
+		break;
+	case 25:
+		host->speed = KW_I2C_MODE_25KHZ;
+		break;
+	}	
+
+	host->mode = pmac_low_i2c_mode_std;
+	host->base = ioremap(np->addrs[0].address + aoffset,
+						np->addrs[0].size);
+	host->func = keywest_low_i2c_func;
+}
+
+/*
+ *
+ * PMU implementation
+ *
+ */
+
+
+#ifdef CONFIG_ADB_PMU
+
+static int pmu_low_i2c_func(struct low_i2c_host *host, u8 addr, u8 sub, u8 *data, int len)
+{
+	// TODO
+	return -ENODEV;
+}
+
+static void pmu_low_i2c_add(struct device_node *np)
+{
+	struct low_i2c_host	*host = find_low_i2c_host(NULL);
+
+	if (host == NULL) {
+		printk(KERN_ERR "low_i2c: Can't allocate host for %s\n",
+		       np->full_name);
+		return;
+	}
+	memset(host, 0, sizeof(*host));
+
+	init_MUTEX(&host->mutex);
+	host->np = of_node_get(np);	
+	host->num_channels = 3;
+	host->mode = pmac_low_i2c_mode_std;
+	host->func = pmu_low_i2c_func;
+}
+
+#endif /* CONFIG_ADB_PMU */
+
+void __init pmac_init_low_i2c(void)
+{
+	struct device_node *np;
+
+	/* Probe keywest-i2c busses */
+	np = of_find_compatible_node(NULL, "i2c", "keywest-i2c");
+	while(np) {
+		keywest_low_i2c_add(np);
+		np = of_find_compatible_node(np, "i2c", "keywest-i2c");
+	}
+
+#ifdef CONFIG_ADB_PMU
+	/* Probe PMU busses */
+	np = of_find_node_by_name(NULL, "via-pmu");
+	if (np)
+		pmu_low_i2c_add(np);
+#endif /* CONFIG_ADB_PMU */
+
+	/* TODO: Add CUDA support as well */
+}
+
+int pmac_low_i2c_lock(struct device_node *np)
+{
+	struct low_i2c_host *host = find_low_i2c_host(np);
+
+	if (!host)
+		return -ENODEV;
+	down(&host->mutex);
+	return 0;
+}
+EXPORT_SYMBOL(pmac_low_i2c_lock);
+
+int pmac_low_i2c_unlock(struct device_node *np)
+{
+	struct low_i2c_host *host = find_low_i2c_host(np);
+
+	if (!host)
+		return -ENODEV;
+	up(&host->mutex);
+	return 0;
+}
+EXPORT_SYMBOL(pmac_low_i2c_unlock);
+
+
+int pmac_low_i2c_open(struct device_node *np, int channel)
+{
+	struct low_i2c_host *host = find_low_i2c_host(np);
+
+	if (!host)
+		return -ENODEV;
+
+	if (channel >= host->num_channels)
+		return -EINVAL;
+
+	down(&host->mutex);
+	host->is_open = 1;
+	host->channel = channel;
+
+	return 0;
+}
+EXPORT_SYMBOL(pmac_low_i2c_open);
+
+int pmac_low_i2c_close(struct device_node *np)
+{
+	struct low_i2c_host *host = find_low_i2c_host(np);
+
+	if (!host)
+		return -ENODEV;
+
+	host->is_open = 0;
+	up(&host->mutex);
+
+	return 0;
+}
+EXPORT_SYMBOL(pmac_low_i2c_close);
+
+int pmac_low_i2c_setmode(struct device_node *np, int mode)
+{
+	struct low_i2c_host *host = find_low_i2c_host(np);
+
+	if (!host)
+		return -ENODEV;
+	WARN_ON(!host->is_open);
+	host->mode = mode;
+
+	return 0;
+}
+EXPORT_SYMBOL(pmac_low_i2c_setmode);
+
+int pmac_low_i2c_xfer(struct device_node *np, u8 addrdir, u8 subaddr, u8 *data, int len)
+{
+	struct low_i2c_host *host = find_low_i2c_host(np);
+
+	if (!host)
+		return -ENODEV;
+	WARN_ON(!host->is_open);
+
+	return host->func(host, addrdir, subaddr, data, len);
+}
+EXPORT_SYMBOL(pmac_low_i2c_xfer);
+