[PATCH POWERPC] i2c: adds support for i2c bus on Frescale CPM1/CPM2controllers

[Jochen Friedrich]

Using the port of 2.4 code from Vitaly Bordug <vitb@xxxxxxxxxxxxxxxxxxx>
and the actual algorithm used by the i2c driver of the DBox code on
cvs.tuxboc.org from Tmbinc, Gillem (htoa@xxxxxxx). Renamed i2c-rpx.c and
i2c-algo-8xx.c to i2c-cpm.c and converted the driver to an
of_platform_driver.

Signed-off-by: Jochen Friedrich <jochen@xxxxxxxx>
---
arch/powerpc/boot/dts/mpc866ads.dts          |   10 +
arch/powerpc/boot/dts/mpc885ads.dts          |   10 +
arch/powerpc/platforms/8xx/mpc885ads_setup.c |    5 +
drivers/i2c/busses/Kconfig                   |   10 +
drivers/i2c/busses/Makefile                  |    1 +
drivers/i2c/busses/i2c-cpm.c                 |  776 ++++++++++++++++++++++++++
6 files changed, 812 insertions(+), 0 deletions(-)
create mode 100644 drivers/i2c/busses/i2c-cpm.c

diff --git a/arch/powerpc/boot/dts/mpc866ads.dts b/arch/powerpc/boot/dts/mpc866ads.dts
index 90f2293..c79cac1 100644
--- a/arch/powerpc/boot/dts/mpc866ads.dts
+++ b/arch/powerpc/boot/dts/mpc866ads.dts
@@ -141,6 +141,16 @@
				interrupts = <1e 3>;
				interrupt-parent = <&Cpm_pic>;
			};
+
+			i2c@860 {
+				compatible = "fsl,mpc866-i2c",
+					     "fsl,cpm1-i2c",
+					     "fsl,cpm-i2c";
+				reg = <860 20 3c80 30>;
+				interrupts = <10 3>;
+				interrupt-parent = <&Cpm_pic>;
+				fsl,cpm-command = <0010>;
+			};
		};
	};
};
diff --git a/arch/powerpc/boot/dts/mpc885ads.dts b/arch/powerpc/boot/dts/mpc885ads.dts
index 8848e63..fd9c9d7 100644
--- a/arch/powerpc/boot/dts/mpc885ads.dts
+++ b/arch/powerpc/boot/dts/mpc885ads.dts
@@ -213,6 +213,16 @@
				fsl,cpm-command = <0080>;
				linux,network-index = <2>;
			};
+
+			i2c@860 {
+				compatible = "fsl,mpc885-i2c",
+					     "fsl,cpm1-i2c",
+					     "fsl,cpm-i2c";
+				reg = <860 20 3c80 30>;
+				interrupts = <10>;
+				interrupt-parent = <&CPM_PIC>;
+				fsl,cpm-command = <0010>;
+			};
		};
	};

diff --git a/arch/powerpc/platforms/8xx/mpc885ads_setup.c b/arch/powerpc/platforms/8xx/mpc885ads_setup.c
index 2cf1b6a..4377521 100644
--- a/arch/powerpc/platforms/8xx/mpc885ads_setup.c
+++ b/arch/powerpc/platforms/8xx/mpc885ads_setup.c
@@ -157,6 +157,11 @@ static struct cpm_pin mpc885ads_pins[] = {
	{CPM_PORTE, 28, CPM_PIN_OUTPUT},
	{CPM_PORTE, 29, CPM_PIN_OUTPUT},
#endif
+	/* I2C */
+#ifdef CONFIG_I2C_8XX
+	{CPM_PORTB, 26, CPM_PIN_INPUT | CPM_PIN_OPENDRAIN},
+	{CPM_PORTB, 27, CPM_PIN_INPUT | CPM_PIN_OPENDRAIN},
+#endif
};

static void __init init_ioports(void)
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index c466c6c..5950172 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -114,6 +114,16 @@ config I2C_BLACKFIN_TWI_CLK_KHZ
	help
	  The unit of the TWI clock is kHz.

+config I2C_CPM
+	tristate "Freescale CPM1 or CPM2 (MPC8xx/826x)"
+	depends on (CPM1 || CPM2) && I2C && PPC_OF
+	help
+	  This supports the use of the I2C interface on Freescale
+	  processors with CPM1 or CPM2.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called i2c-cpm.
+
config I2C_DAVINCI
	tristate "DaVinci I2C driver"
	depends on ARCH_DAVINCI
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 81d43c2..a395555 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_I2C_AMD8111)	+= i2c-amd8111.o
obj-$(CONFIG_I2C_AT91)		+= i2c-at91.o
obj-$(CONFIG_I2C_AU1550)	+= i2c-au1550.o
obj-$(CONFIG_I2C_BLACKFIN_TWI)	+= i2c-bfin-twi.o
+obj-$(CONFIG_I2C_CPM)		+= i2c-cpm.o
obj-$(CONFIG_I2C_DAVINCI)	+= i2c-davinci.o
obj-$(CONFIG_I2C_ELEKTOR)	+= i2c-elektor.o
obj-$(CONFIG_I2C_GPIO)		+= i2c-gpio.o
diff --git a/drivers/i2c/busses/i2c-cpm.c b/drivers/i2c/busses/i2c-cpm.c
new file mode 100644
index 0000000..c3714f6
--- /dev/null
+++ b/drivers/i2c/busses/i2c-cpm.c
@@ -0,0 +1,776 @@
+/*
+ * Freescale CPM1/CPM2 I2C interface.
+ * Copyright (c) 1999 Dan Malek (dmalek@xxxxxxx).
+ *
+ * moved into proper i2c interface;
+ * Brad Parker (brad@xxxxxxxxxxx)
+ *
+ * (C) 2007 Montavista Software, Inc.
+ * Vitaly Bordug <vitb@xxxxxxxxxxxxxxxxxxx>
+ *
+ * RPX lite specific parts of the i2c interface
+ * Update:  There actually isn't anything RPXLite-specific about this module.
+ * This should work for most any CPM board.  The console messages have been
+ * changed to eliminate RPXLite references.
+ *
+    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.
+ *
+ * moved into proper i2c interface; separated out platform specific
+ * parts into i2c-8xx.c
+ * Brad Parker (brad@xxxxxxxxxxx)
+ *
+ * Parts from dbox2_i2c.c (cvs.tuxbox.org)
+ * (C) 2000-2001 Tmbinc, Gillem (htoa@xxxxxxx)
+ *
+ * (C) 2007 Montavista Software, Inc.
+ * Vitaly Bordug <vitb@xxxxxxxxxxxxxxxxxxx>
+ *
+ * Converted to of_platform_device. Renamed to i2c-cpm.c.
+ * (C) 2007 Jochen Friedrich <jochen@xxxxxxxx>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/stddef.h>
+#include <linux/i2c.h>
+#include <linux/io.h>
+#include <linux/time.h>
+#include <linux/dma-mapping.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <sysdev/fsl_soc.h>
+#include <asm/cpm.h>
+
+/* Try to define this if you have an older CPU (earlier than rev D4) */
+/* However, better use a GPIO based bitbang driver in this case :/   */
+#undef	I2C_CHIP_ERRATA
+
+#define CPM_MAX_READ    513
+#define CPM_MAXBD       4
+
+/* Buffer descriptors used by many of the CPM protocols. */
+typedef struct cpm_buf_desc {
+       ushort  cbd_sc;         /* Status and Control */
+       ushort  cbd_datlen;     /* Data length in buffer */
+       uint    cbd_bufaddr;    /* Buffer address in host memory */
+} cbd_t;
+
+#define BD_I2C_EMPTY	(0x8000)	/* Receive is empty */
+#define BD_I2C_READY	(0x8000)	/* Transmit is ready */
+#define BD_I2C_WRAP	(0x2000)	/* Last buffer descriptor */
+#define BD_I2C_INTRPT	(0x1000)	/* Interrupt on change */
+#define BD_I2C_LAST	(0x0800)	/* Last buffer in frame */
+#define BD_I2C_START	(0x0400)	/* Send start condition */
+#define BD_I2C_NAK	(0x0004)	/* NAK - did not respond */
+#define BD_I2C_OV	(0x0002)	/* OV - receive overrun */
+#define BD_I2C_UN	(0x0002)	/* UN - transmit underrun */
+#define BD_I2C_CL	(0x0001)	/* Collision */
+
+#define CPM_CR_INIT_TRX		(0x00)
+#define CPM_CR_CLOSE_RXBD	(0x07)
+
+#define I2C_EB			(0x10) /* Big endian mode */
+
+/* I2C parameter RAM. */
+typedef struct i2c_ram {
+	ushort  rbase;		/* Rx Buffer descriptor base address */
+	ushort  tbase;		/* Tx Buffer descriptor base address */
+	u_char  rfcr;		/* Rx function code */
+	u_char  tfcr;		/* Tx function code */
+	ushort  mrblr;		/* Max receive buffer length */
+	uint    rstate;		/* Internal */
+	uint    rdp;		/* Internal */
+	ushort  rbptr;		/* Rx Buffer descriptor pointer */
+	ushort  rbc;		/* Internal */
+	uint    rxtmp;		/* Internal */
+	uint    tstate;		/* Internal */
+	uint    tdp;		/* Internal */
+	ushort  tbptr;		/* Tx Buffer descriptor pointer */
+	ushort  tbc;		/* Internal */
+	uint    txtmp;		/* Internal */
+	char    res1[4];	/* Reserved */
+	ushort  rpbase;		/* Relocation pointer */
+} i2c_ram_t;
+
+/* I2C Registers */
+typedef struct i2c_reg {
+	u8	i2mod;
+	u8	res1[3];
+	u8	i2add;
+	u8	res2[3];
+	u8	i2brg;
+	u8	res3[3];
+	u8	i2com;
+	u8	res4[3];
+	u8	i2cer;
+	u8	res5[3];
+	u8	i2cmr;
+} i2c_reg_t;
+
+struct cpm_i2c {
+	char *base;
+	struct of_device *ofdev;
+	struct i2c_adapter adap;
+	uint dp_addr;
+	int reloc;
+	int version; /* CPM1=1, CPM2=2 */
+	int irq;
+	int cp_command;
+	i2c_reg_t __iomem *i2c_reg;
+	i2c_ram_t __iomem *i2c_ram;
+	u16 i2c_addr;
+	wait_queue_head_t i2c_wait;
+	struct mutex i2c_mutex; /* Protects I2C CPM */
+	u_char *txbuf[CPM_MAXBD];
+	u_char *rxbuf[CPM_MAXBD];
+	u32 txdma[CPM_MAXBD];
+	u32 rxdma[CPM_MAXBD];
+};
+
+static irqreturn_t cpm_i2c_interrupt(int irq, void *dev_id)
+{
+	struct i2c_adapter *adap;
+	struct cpm_i2c *cpm;
+	i2c_reg_t __iomem *i2c_reg;
+	int i;
+
+	adap = (struct i2c_adapter *) dev_id;
+	cpm = i2c_get_adapdata(adap);
+	i2c_reg = cpm->i2c_reg;
+
+	/* Clear interrupt.
+	 */
+	i = in_8(&i2c_reg->i2cer);
+	out_8(&i2c_reg->i2cer, i);
+
+	dev_dbg(&adap->dev, "Interrupt: %x\n", i);
+
+	/* Get 'me going again.
+	 */
+	wake_up_interruptible(&cpm->i2c_wait);
+
+	return i ? IRQ_HANDLED : IRQ_NONE;
+}
+
+static void cpm_reset_i2c_params(struct cpm_i2c *cpm)
+{
+	i2c_ram_t __iomem *i2c_ram = cpm->i2c_ram;
+
+	/* Set up the IIC parameters in the parameter ram.
+	 */
+	out_be16(&i2c_ram->tbase, cpm->dp_addr);
+	out_be16(&i2c_ram->rbase, cpm->dp_addr + sizeof(cbd_t) * CPM_MAXBD);
+
+	out_8(&i2c_ram->tfcr, I2C_EB);
+	out_8(&i2c_ram->rfcr, I2C_EB);
+
+	out_be16(&i2c_ram->mrblr, CPM_MAX_READ);
+
+	out_be32(&i2c_ram->rstate, 0);
+	out_be32(&i2c_ram->rdp, 0);
+	out_be16(&i2c_ram->rbptr, in_be16(&i2c_ram->rbase));
+	out_be16(&i2c_ram->rbc, 0);
+	out_be32(&i2c_ram->rxtmp, 0);
+	out_be32(&i2c_ram->tstate, 0);
+	out_be32(&i2c_ram->tdp, 0);
+	out_be16(&i2c_ram->tbptr, in_be16(&i2c_ram->tbase));
+	out_be16(&i2c_ram->tbc, 0);
+	out_be32(&i2c_ram->txtmp, 0);
+}
+
+static int cpm_i2c_init(struct i2c_adapter *adap)
+{
+	struct cpm_i2c *cpm = i2c_get_adapdata(adap);
+	i2c_ram_t __iomem *i2c_ram = cpm->i2c_ram;
+	i2c_reg_t __iomem *i2c_reg = cpm->i2c_reg;
+	unsigned char brg;
+	int ret, i;
+
+	pr_debug("i2c-cpm: cpm_i2c_init()\n");
+
+	ret = 0;
+	init_waitqueue_head(&cpm->i2c_wait);
+	mutex_init(&cpm->i2c_mutex);
+
+	/* Initialize Tx/Rx parameters. */
+
+	cpm_reset_i2c_params(cpm);
+
+	pr_debug("i2c-cpm: i2c_ram %x, dp_addr 0x%x\n", (uint) cpm->i2c_ram,
+		cpm->dp_addr);
+	pr_debug("i2c-cpm: tbase %d, rbase %d\n",
+		in_be16(&i2c_ram->tbase), in_be16(&i2c_ram->rbase));
+
+	cpm_command(cpm->cp_command, CPM_CR_INIT_TRX);
+
+	/* Select an invalid address. Just make sure we don't use loopback mode
+	 */
+	out_8(&i2c_reg->i2add, 0xfe);
+
+	/* Make clock run at 60 kHz. */
+
+	brg = get_brgfreq() / (32 * 2 * 60000) - 3;
+	out_8(&i2c_reg->i2brg, brg);
+
+	out_8(&i2c_reg->i2mod, 0x00);
+	out_8(&i2c_reg->i2com, 0x01);	/* Master mode */
+
+	/* Disable interrupts. */
+	out_8(&i2c_reg->i2cmr, 0);
+	out_8(&i2c_reg->i2cer, 0xff);
+
+	/* Allocate TX and RX buffers */
+	for (i = 0; i < CPM_MAXBD; i++) {
+		cpm->rxbuf[i] = dma_alloc_coherent(
+			NULL, CPM_MAX_READ + 1, &cpm->rxdma[i], GFP_KERNEL);
+		if (!cpm->rxbuf[i]) {
+			ret = -ENOMEM;
+			goto out;
+		}
+		cpm->txbuf[i] = (unsigned char *)dma_alloc_coherent(
+			NULL, CPM_MAX_READ + 1, &cpm->txdma[i], GFP_KERNEL);
+		if (!cpm->txbuf[i]) {
+			ret = -ENOMEM;
+			goto out;
+		}
+	}
+
+	/* Install interrupt handler.
+	 */
+	ret = request_irq(cpm->irq, cpm_i2c_interrupt, 0, "cpm_i2c", adap);
+	if (ret)
+		goto out;
+
+	return 0;
+
+out:
+	for (i = 0; i < CPM_MAXBD; i++) {
+		if (cpm->rxbuf[i])
+			dma_free_coherent(NULL, CPM_MAX_READ + 1,
+				cpm->rxbuf[i], cpm->rxdma[i]);
+		if (cpm->txbuf[i])
+			dma_free_coherent(NULL, CPM_MAX_READ + 1,
+				cpm->txbuf[i], cpm->txdma[i]);
+	}
+	return ret;
+}
+
+static int cpm_i2c_shutdown(struct i2c_adapter *adap)
+{
+	struct cpm_i2c *cpm = i2c_get_adapdata(adap);
+	int i;
+
+	i2c_reg_t __iomem *i2c_reg = cpm->i2c_reg;
+
+	/* Shut down IIC. */
+	out_8(&i2c_reg->i2mod, in_8(&i2c_reg->i2mod) | ~1);
+	out_8(&i2c_reg->i2cmr, 0);
+	out_8(&i2c_reg->i2cer, 0xff);
+
+	for (i = 0; i < CPM_MAXBD; i++) {
+		if (cpm->rxbuf[i])
+			dma_free_coherent(NULL, CPM_MAX_READ + 1,
+				cpm->rxbuf[i], cpm->rxdma[i]);
+		if (cpm->txbuf[i])
+			dma_free_coherent(NULL, CPM_MAX_READ + 1,
+				cpm->txbuf[i], cpm->txdma[i]);
+	}
+
+	free_irq(cpm->irq, adap);
+
+	return 0;
+}
+
+static void cpm_i2c_force_close(struct i2c_adapter *adap)
+{
+	struct cpm_i2c *cpm = i2c_get_adapdata(adap);
+	i2c_reg_t __iomem *i2c_reg = cpm->i2c_reg;
+
+	dev_dbg(&adap->dev, "cpm_i2c_force_close()\n");
+
+	cpm_command(cpm->cp_command, CPM_CR_CLOSE_RXBD);
+
+	out_8(&i2c_reg->i2cmr, 0x00);	/* Disable all interrupts */
+	out_8(&i2c_reg->i2cer, 0xff);
+}
+
+static void cpm_i2c_parse_message(struct i2c_adapter *adap,
+	struct i2c_msg *pmsg, int num, int tx, int rx)
+{
+	cbd_t *tbdf, *rbdf;
+	u_char addr;
+	u_char *tb;
+	u_char *rb;
+	struct cpm_i2c *cpm = i2c_get_adapdata(adap);
+	i2c_ram_t __iomem *i2c_ram = cpm->i2c_ram;
+	int i, dscan;
+
+	tbdf = (cbd_t *) cpm_muram_addr(in_be16(&i2c_ram->tbase));
+	rbdf = (cbd_t *) cpm_muram_addr(in_be16(&i2c_ram->rbase));
+
+	/* This chip can't do zero length writes. However, the i2c core uses
+	   them to scan for devices. The best we can do is to convert them
+	   into 1 byte reads */
+
+	dscan = ((pmsg->len == 0) && (num == 1));
+
+	addr = pmsg->addr << 1;
+	if ((pmsg->flags & I2C_M_RD) || dscan)
+		addr |= 1;
+
+	tb = cpm->txbuf[tx];
+	rb = cpm->rxbuf[rx];
+
+	/* Align read buffer */
+	rb = (u_char *) (((ulong) rb + 1) & ~1);
+
+	if ((pmsg->flags & I2C_M_RD) || dscan) {
+		/* To read, we need an empty buffer of the proper length.
+		 * All that is used is the first byte for address, the remainder
+		 * is just used for timing (and doesn't really have to exist).
+		 */
+		tb[0] = addr;		/* Device address byte w/rw flag */
+
+		dev_dbg(&adap->dev, "cpm_i2c_read(abyte=0x%x)\n", addr);
+		tbdf[tx].cbd_bufaddr = cpm->txdma[tx];
+
+		if (dscan)
+			tbdf[tx].cbd_datlen = 2;
+		else
+			tbdf[tx].cbd_datlen = pmsg->len + 1;
+
+		tbdf[tx].cbd_sc = 0;
+
+		if (!(pmsg->flags & I2C_M_NOSTART))
+			tbdf[tx].cbd_sc |= BD_I2C_START;
+		if (tx + 1 == num)
+			tbdf[tx].cbd_sc |= BD_I2C_LAST | BD_I2C_WRAP;
+
+		rbdf[rx].cbd_datlen = 0;
+		rbdf[rx].cbd_bufaddr = ((cpm->rxdma[rx] + 1) & ~1);
+		rbdf[rx].cbd_sc = BD_I2C_EMPTY | BD_I2C_INTRPT;
+
+		if (rx + 1 == CPM_MAXBD)
+			tbdf[rx].cbd_sc |= BD_I2C_WRAP;
+
+		eieio();
+		tbdf[tx].cbd_sc |= BD_I2C_READY;
+	} else {
+		tb[0] = addr;		/* Device address byte w/rw flag */
+		for (i = 0; i < pmsg->len; i++)
+			tb[i+1] = pmsg->buf[i];
+
+		dev_dbg(&adap->dev, "cpm_iic_write(abyte=0x%x)\n", addr);
+
+		tbdf[tx].cbd_bufaddr = cpm->txdma[tx];
+		tbdf[tx].cbd_datlen = pmsg->len + 1;
+		tbdf[tx].cbd_sc = 0;
+
+		if (!(pmsg->flags & I2C_M_NOSTART))
+			tbdf[tx].cbd_sc |= BD_I2C_START;
+
+		if (tx + 1 == num)
+			tbdf[tx].cbd_sc |= BD_I2C_LAST | BD_I2C_WRAP;
+
+		eieio();
+		tbdf[tx].cbd_sc |= BD_I2C_READY | BD_I2C_INTRPT;
+
+		dev_dbg(&adap->dev, "tx sc %d %04x\n",
+			tx, tbdf[tx].cbd_sc);
+	}
+}
+
+static int cpm_i2c_check_message(struct i2c_adapter *adap,
+	struct i2c_msg *pmsg, int tx, int rx)
+{
+	cbd_t *tbdf, *rbdf;
+	u_char *tb;
+	u_char *rb;
+	struct cpm_i2c *cpm = i2c_get_adapdata(adap);
+	i2c_ram_t __iomem *i2c_ram = cpm->i2c_ram;
+	int i;
+
+	tbdf = (cbd_t *) cpm_muram_addr(in_be16(&i2c_ram->tbase));
+	rbdf = (cbd_t *) cpm_muram_addr(in_be16(&i2c_ram->rbase));
+
+	tb = cpm->txbuf[tx];
+	rb = cpm->rxbuf[rx];
+
+	/* Align read buffer */
+	rb = (u_char *) (((uint) rb + 1) & ~1);
+
+	if (pmsg->flags & I2C_M_RD) {
+		dev_dbg(&adap->dev, "rx sc %04x, rx sc %04x\n",
+			tbdf[tx].cbd_sc, rbdf[rx].cbd_sc);
+
+		if (tbdf[tx].cbd_sc & BD_I2C_NAK) {
+			dev_dbg(&adap->dev, "IIC read; No ack\n");
+
+			if (pmsg->flags & I2C_M_IGNORE_NAK)
+				return 0;
+			else
+				return -EIO;
+		}
+		if (rbdf[rx].cbd_sc & BD_I2C_EMPTY) {
+			dev_dbg(&adap->dev,
+				"IIC read; complete but rbuf empty\n");
+			return -EREMOTEIO;
+		}
+		if (rbdf[rx].cbd_sc & BD_I2C_OV) {
+			dev_dbg(&adap->dev, "IIC read; Overrun\n");
+			return -EREMOTEIO;
+		}
+		for (i = 0; i < pmsg->len; i++)
+			pmsg->buf[i] = rb[i];
+	} else {
+		dev_dbg(&adap->dev, "tx sc %d %04x\n", tx, tbdf[tx].cbd_sc);
+
+		if (tbdf[tx].cbd_sc & BD_I2C_NAK) {
+			dev_dbg(&adap->dev, "IIC write; No ack\n");
+
+			if (pmsg->flags & I2C_M_IGNORE_NAK)
+				return 0;
+			else
+				return -EIO;
+		}
+		if (tbdf[tx].cbd_sc & BD_I2C_UN) {
+			dev_dbg(&adap->dev, "IIC write; Underrun\n");
+			return -EIO;
+		}
+		if (tbdf[tx].cbd_sc & BD_I2C_CL) {
+			dev_dbg(&adap->dev, "IIC write; Collision\n");
+			return -EIO;
+		}
+	}
+	return 0;
+}
+
+static int cpm_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
+{
+	struct cpm_i2c *cpm = i2c_get_adapdata(adap);
+	i2c_reg_t __iomem *i2c_reg = cpm->i2c_reg;
+	i2c_ram_t __iomem *i2c_ram = cpm->i2c_ram;
+	struct i2c_msg *pmsg, *rmsg;
+	int ret, i;
+	int tptr;
+	int rptr;
+	cbd_t *tbdf, *rbdf;
+
+	if (num > CPM_MAXBD)
+		return -EINVAL;
+
+	/* Check if we have any oversized READ requests */
+	for (i = 0; i < num; i++) {
+		pmsg = &msgs[i];
+		if (pmsg->len >= CPM_MAX_READ)
+			return -EINVAL;
+	}
+
+	mutex_lock(&cpm->i2c_mutex);
+
+	/* Reset to use first buffer */
+	out_be16(&i2c_ram->rbptr, in_be16(&i2c_ram->rbase));
+	out_be16(&i2c_ram->tbptr, in_be16(&i2c_ram->tbase));
+
+	tbdf = (cbd_t *) cpm_muram_addr(in_be16(&i2c_ram->tbase));
+	rbdf = (cbd_t *) cpm_muram_addr(in_be16(&i2c_ram->rbase));
+
+	tptr = 0;
+	rptr = 0;
+
+	while (tptr < num) {
+		pmsg = &msgs[tptr];
+		dev_dbg(&adap->dev, "i2c-algo-cpm.o: " "R: %d T: %d\n",
+			rptr, tptr);
+
+		cpm_i2c_parse_message(adap, pmsg, num, tptr, rptr);
+		if (pmsg->flags & I2C_M_RD)
+			rptr++;
+		tptr++;
+	}
+	/* Start transfer now */
+	/* Chip bug, set enable here */
+	out_8(&i2c_reg->i2cmr, 0x13);	/* Enable some interupts */
+	out_8(&i2c_reg->i2cer, 0xff);
+	out_8(&i2c_reg->i2mod, in_8(&i2c_reg->i2mod) | 1);	/* Enable */
+	/* Begin transmission */
+	out_8(&i2c_reg->i2com, in_8(&i2c_reg->i2com) | 0x80);
+
+	tptr = 0;
+	rptr = 0;
+
+	while (tptr < num) {
+		/* Check for outstanding messages */
+		dev_dbg(&adap->dev, "test ready.\n");
+		if (!(tbdf[tptr].cbd_sc & BD_I2C_READY)) {
+			dev_dbg(&adap->dev, "ready.\n");
+			rmsg = &msgs[tptr];
+			ret = cpm_i2c_check_message(adap, rmsg, tptr, rptr);
+			tptr++;
+			if (rmsg->flags & I2C_M_RD)
+				rptr++;
+			if (ret) {
+				cpm_i2c_force_close(adap);
+				mutex_unlock(&cpm->i2c_mutex);
+				return ret;
+			}
+		} else {
+			dev_dbg(&adap->dev, "not ready.\n");
+			ret = wait_event_interruptible_timeout(cpm->i2c_wait,
+				!(tbdf[tptr].cbd_sc & BD_I2C_READY), 1 * HZ);
+			if (ret == 0) {
+				cpm_i2c_force_close(adap);
+				dev_dbg(&adap->dev, "I2C read: timeout!\n");
+				mutex_unlock(&cpm->i2c_mutex);
+				return -EREMOTEIO;
+			}
+		}
+	}
+#ifdef I2C_CHIP_ERRATA
+	/* Chip errata, clear enable. This is not needed on rev D4 CPUs.
+	   Disabling I2C too early may cause too short stop condition */
+	udelay(4);
+	out_8(&i2c_reg->i2mod, in_8(&i2c_reg->i2mod) | ~1);
+#endif
+	mutex_unlock(&cpm->i2c_mutex);
+	return (num);
+}
+
+static u32 cpm_i2c_func(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+/* -----exported algorithm data: -------------------------------------	*/
+
+static struct i2c_algorithm cpm_i2c_algo = {
+	.master_xfer = cpm_i2c_xfer,
+	.functionality = cpm_i2c_func,
+};
+
+/*
+ * registering functions to load algorithms at runtime
+ */
+int i2c_cpm_add_bus(struct i2c_adapter *adap)
+{
+	int res;
+
+	pr_debug("i2c-cpm: hw routines for %s registered.\n", adap->name);
+
+	/* register new adapter to i2c module... */
+
+	adap->algo = &cpm_i2c_algo;
+
+	res = cpm_i2c_init(adap);
+
+	if (res)
+		return res;
+
+	return i2c_add_adapter(adap);
+}
+
+int i2c_cpm_del_bus(struct i2c_adapter *adap)
+{
+	i2c_del_adapter(adap);
+
+	return cpm_i2c_shutdown(adap);
+}
+
+static const struct i2c_adapter cpm_ops = {
+	.owner		= THIS_MODULE,
+	.name		= "i2c-cpm",
+	.id		= I2C_HW_MPC8XX_EPON,
+	.class		= I2C_CLASS_HWMON,
+};
+
+static int i2c_cpm_setup(struct cpm_i2c *i2c)
+{
+	struct of_device *ofdev = i2c->ofdev;
+	const u32 *data;
+	int len, ret;
+	void __iomem *i2c_base;
+
+	/* Pointer to Communication Processor
+	 */
+	i2c->irq = of_irq_to_resource(ofdev->node, 0, NULL);
+	if (i2c->irq == NO_IRQ)
+		return -EINVAL;
+
+	if (of_device_is_compatible(ofdev->node, "fsl,cpm1-i2c")) {
+
+		/* IIC parameter RAM */
+		i2c->i2c_ram = of_iomap(ofdev->node, 1);
+		if (i2c->i2c_ram == NULL)
+			return -EINVAL;
+	
+		/* Check for and use a microcode relocation patch.
+		 */
+		i2c->reloc = i2c->i2c_ram->rpbase;
+
+		/* Maybe should use cpm_muram_alloc instead of hardcoding
+		 * this in micropatch.c */
+		if (i2c->reloc) {
+			iounmap(i2c->i2c_ram);
+			i2c->i2c_ram = cpm_muram_addr(i2c->i2c_ram->rpbase);
+		}
+		i2c->version = 1;
+	} else if (of_device_is_compatible(ofdev->node, "fsl,cpm2-i2c")) {
+		i2c_base = of_iomap(ofdev->node, 1);
+		if (i2c_base == NULL)
+			return -EINVAL;
+		i2c->i2c_addr = cpm_muram_alloc(0x30, 64);
+		i2c->i2c_ram = cpm_muram_addr(i2c->i2c_addr);
+		out_be16(i2c_base, i2c->i2c_addr);
+		iounmap(i2c_base);
+		i2c->version = 2;
+	} else
+		return -EINVAL;
+
+	/* I2C control/status registers */
+	i2c->i2c_reg = of_iomap(ofdev->node, 0);
+	if (i2c->i2c_reg == NULL) {
+		ret = -EINVAL;
+		goto out_ram;
+	}
+
+	/* Allocate space for two transmit and two receive buffer
+	 * descriptors in the DP ram.
+	 */
+	i2c->dp_addr = cpm_muram_alloc(sizeof(cbd_t) * 4, 8);
+	if (!i2c->dp_addr) {
+		ret = -ENOMEM;
+		goto out_reg;
+	}
+
+	data = of_get_property(ofdev->node, "fsl,cpm-command", &len);
+	if (!data || len != 4) {
+		ret = -EINVAL;
+		goto out_muram;
+	}
+
+	i2c->cp_command = *data;
+	return 0;
+
+out_muram:
+	cpm_muram_free(i2c->dp_addr);
+out_reg:
+	iounmap(i2c->i2c_reg);
+out_ram:
+	if ((i2c->version == 1) && (!i2c->reloc))
+		iounmap(i2c->i2c_ram);
+	if (i2c->version == 2)
+		cpm_muram_free(i2c->i2c_addr);
+	return ret;
+}
+
+static void i2c_cpm_release(struct cpm_i2c *i2c)
+{
+	cpm_muram_free(i2c->dp_addr);
+	iounmap(i2c->i2c_reg);
+
+	if ((i2c->version == 1) && (!i2c->reloc))
+		iounmap(i2c->i2c_ram);
+	if (i2c->version == 2)
+		cpm_muram_free(i2c->i2c_addr);
+
+	return;
+}
+
+static int i2c_cpm_probe(struct of_device *ofdev,
+			 const struct of_device_id *match)
+{
+	int result;
+	struct cpm_i2c *i2c;
+
+	i2c = kzalloc(sizeof(struct cpm_i2c), GFP_KERNEL);
+	if (!i2c)
+		return -ENOMEM;
+
+	i2c->ofdev = ofdev;
+
+	result = i2c_cpm_setup(i2c);
+	if (result) {
+		printk(KERN_ERR "i2c-cpm: Unable to register resources\n");
+		goto out;
+	}
+
+	dev_set_drvdata(&ofdev->dev, i2c);
+
+	i2c->adap = cpm_ops;
+	i2c_set_adapdata(&i2c->adap, i2c);
+	i2c->adap.dev.parent = &ofdev->dev;
+
+	result = i2c_cpm_add_bus(&i2c->adap);
+	if (result < 0) {
+		printk(KERN_ERR "i2c-cpm: Unable to register with I2C\n");
+		goto out;
+	}
+	return 0;
+
+out:
+	kfree(i2c);
+	return result;
+}
+
+static int i2c_cpm_remove(struct of_device *ofdev)
+{
+	struct cpm_i2c *i2c = dev_get_drvdata(&ofdev->dev);
+
+	i2c_cpm_del_bus(&i2c->adap);
+	dev_set_drvdata(&ofdev->dev, NULL);
+
+	i2c_cpm_release(i2c);
+	kfree(i2c);
+	return 0;
+}
+
+static struct of_device_id i2c_cpm_match[] = {
+	{
+		.compatible = "fsl,cpm-i2c",
+	},
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, i2c_cpm_match);
+
+static struct of_platform_driver i2c_cpm_driver = {
+	.name		= "fsl-i2c-cpm",
+	.match_table	= i2c_cpm_match,
+	.probe		= i2c_cpm_probe,
+	.remove		= i2c_cpm_remove,
+};
+
+static int __init i2c_cpm_init(void)
+{
+	return of_register_platform_driver(&i2c_cpm_driver);
+}
+
+static void __exit i2c_cpm_exit(void)
+{
+	of_unregister_platform_driver(&i2c_cpm_driver);
+}
+
+module_init(i2c_cpm_init);
+module_exit(i2c_cpm_exit);
+
+MODULE_AUTHOR("Dan Malek <dmalek@xxxxxxx>");
+MODULE_DESCRIPTION("I2C-Bus adapter routines for CPM boards");
+MODULE_LICENSE("GPL");
--
1.5.3.7

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