MIPS: Add core files for MIPS SEAD-3 development platform.

More information about the SEAD-3 platform can be found at
<http://www.mips.com/products/development-kits/mips-sead-3/>
on MTI's site. Currently, the M14K family of cores is what
the SEAD-3 is utilised with.

Signed-off-by: Douglas Leung <douglas@mips.com>
Signed-off-by: Chris Dearman <chris@mips.com>
Signed-off-by: Steven J. Hill <sjhill@mips.com>

1 files changed, 435 insertions, 0 deletions

diff --git a/arch/mips/mti-sead3/sead3-pic32-i2c-drv.c b/arch/mips/mti-sead3/sead3-pic32-i2c-drv.c
new file mode 100644
index 00000000000..46509b0a620
--- /dev/null
+++ b/arch/mips/mti-sead3/sead3-pic32-i2c-drv.c
@@ -0,0 +1,435 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2012 MIPS Technologies, Inc.  All rights reserved.
+ */
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/platform_device.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+
+#define PIC32_I2CxCON		0x0000
+#define PIC32_I2CxCONCLR	0x0004
+#define PIC32_I2CxCONSET	0x0008
+#define PIC32_I2CxCONINV	0x000C
+#define  I2CCON_ON		(1<<15)
+#define  I2CCON_FRZ		(1<<14)
+#define  I2CCON_SIDL		(1<<13)
+#define  I2CCON_SCLREL		(1<<12)
+#define  I2CCON_STRICT		(1<<11)
+#define  I2CCON_A10M		(1<<10)
+#define  I2CCON_DISSLW		(1<<9)
+#define  I2CCON_SMEN		(1<<8)
+#define  I2CCON_GCEN		(1<<7)
+#define  I2CCON_STREN		(1<<6)
+#define  I2CCON_ACKDT		(1<<5)
+#define  I2CCON_ACKEN		(1<<4)
+#define  I2CCON_RCEN		(1<<3)
+#define  I2CCON_PEN		(1<<2)
+#define  I2CCON_RSEN		(1<<1)
+#define  I2CCON_SEN		(1<<0)
+
+#define PIC32_I2CxSTAT		0x0010
+#define PIC32_I2CxSTATCLR	0x0014
+#define PIC32_I2CxSTATSET	0x0018
+#define PIC32_I2CxSTATINV	0x001C
+#define  I2CSTAT_ACKSTAT	(1<<15)
+#define  I2CSTAT_TRSTAT		(1<<14)
+#define  I2CSTAT_BCL		(1<<10)
+#define  I2CSTAT_GCSTAT		(1<<9)
+#define  I2CSTAT_ADD10		(1<<8)
+#define  I2CSTAT_IWCOL		(1<<7)
+#define  I2CSTAT_I2COV		(1<<6)
+#define  I2CSTAT_DA		(1<<5)
+#define  I2CSTAT_P		(1<<4)
+#define  I2CSTAT_S		(1<<3)
+#define  I2CSTAT_RW		(1<<2)
+#define  I2CSTAT_RBF		(1<<1)
+#define  I2CSTAT_TBF		(1<<0)
+
+#define PIC32_I2CxADD		0x0020
+#define PIC32_I2CxADDCLR	0x0024
+#define PIC32_I2CxADDSET	0x0028
+#define PIC32_I2CxADDINV	0x002C
+#define PIC32_I2CxMSK		0x0030
+#define PIC32_I2CxMSKCLR	0x0034
+#define PIC32_I2CxMSKSET	0x0038
+#define PIC32_I2CxMSKINV	0x003C
+#define PIC32_I2CxBRG		0x0040
+#define PIC32_I2CxBRGCLR	0x0044
+#define PIC32_I2CxBRGSET	0x0048
+#define PIC32_I2CxBRGINV	0x004C
+#define PIC32_I2CxTRN		0x0050
+#define PIC32_I2CxTRNCLR	0x0054
+#define PIC32_I2CxTRNSET	0x0058
+#define PIC32_I2CxTRNINV	0x005C
+#define PIC32_I2CxRCV		0x0060
+
+struct i2c_platform_data {
+	u32	base;
+	struct i2c_adapter adap;
+	u32	xfer_timeout;
+	u32	ack_timeout;
+	u32	ctl_timeout;
+};
+
+extern u32 pic32_bus_readl(u32 reg);
+extern void pic32_bus_writel(u32 val, u32 reg);
+
+static inline void
+StartI2C(struct i2c_platform_data *adap)
+{
+	pr_debug("StartI2C\n");
+	pic32_bus_writel(I2CCON_SEN, adap->base + PIC32_I2CxCONSET);
+}
+
+static inline void
+StopI2C(struct i2c_platform_data *adap)
+{
+	pr_debug("StopI2C\n");
+	pic32_bus_writel(I2CCON_PEN, adap->base + PIC32_I2CxCONSET);
+}
+
+static inline void
+AckI2C(struct i2c_platform_data *adap)
+{
+	pr_debug("AckI2C\n");
+	pic32_bus_writel(I2CCON_ACKDT, adap->base + PIC32_I2CxCONCLR);
+	pic32_bus_writel(I2CCON_ACKEN, adap->base + PIC32_I2CxCONSET);
+}
+
+static inline void
+NotAckI2C(struct i2c_platform_data *adap)
+{
+	pr_debug("NakI2C\n");
+	pic32_bus_writel(I2CCON_ACKDT, adap->base + PIC32_I2CxCONSET);
+	pic32_bus_writel(I2CCON_ACKEN, adap->base + PIC32_I2CxCONSET);
+}
+
+static inline int
+IdleI2C(struct i2c_platform_data *adap)
+{
+	int i;
+
+	pr_debug("IdleI2C\n");
+	for (i = 0; i < adap->ctl_timeout; i++) {
+		if (((pic32_bus_readl(adap->base + PIC32_I2CxCON) &
+		     (I2CCON_ACKEN | I2CCON_RCEN | I2CCON_PEN | I2CCON_RSEN |
+		      I2CCON_SEN)) == 0) &&
+		    ((pic32_bus_readl(adap->base + PIC32_I2CxSTAT) &
+		     (I2CSTAT_TRSTAT)) == 0))
+			return 0;
+		udelay(1);
+	}
+	return -ETIMEDOUT;
+}
+
+static inline u32
+MasterWriteI2C(struct i2c_platform_data *adap, u32 byte)
+{
+	pr_debug("MasterWriteI2C\n");
+
+	pic32_bus_writel(byte, adap->base + PIC32_I2CxTRN);
+
+	return pic32_bus_readl(adap->base + PIC32_I2CxSTAT) & I2CSTAT_IWCOL;
+}
+
+static inline u32
+MasterReadI2C(struct i2c_platform_data *adap)
+{
+	pr_debug("MasterReadI2C\n");
+
+	pic32_bus_writel(I2CCON_RCEN, adap->base + PIC32_I2CxCONSET);
+
+	while (pic32_bus_readl(adap->base + PIC32_I2CxCON) & I2CCON_RCEN)
+		;
+
+	pic32_bus_writel(I2CSTAT_I2COV, adap->base + PIC32_I2CxSTATCLR);
+
+	return pic32_bus_readl(adap->base + PIC32_I2CxRCV);
+}
+
+static int
+do_address(struct i2c_platform_data *adap, unsigned int addr, int rd)
+{
+	pr_debug("doaddress\n");
+
+	IdleI2C(adap);
+	StartI2C(adap);
+	IdleI2C(adap);
+
+	addr <<= 1;
+	if (rd)
+		addr |= 1;
+
+	if (MasterWriteI2C(adap, addr))
+		return -EIO;
+	IdleI2C(adap);
+	if (pic32_bus_readl(adap->base + PIC32_I2CxSTAT) & I2CSTAT_ACKSTAT)
+		return -EIO;
+	return 0;
+}
+
+static int
+i2c_read(struct i2c_platform_data *adap, unsigned char *buf,
+		    unsigned int len)
+{
+	int	i;
+	u32	data;
+
+	pr_debug("i2c_read\n");
+
+	i = 0;
+	while (i < len) {
+		data = MasterReadI2C(adap);
+		buf[i++] = data;
+		if (i < len)
+			AckI2C(adap);
+		else
+			NotAckI2C(adap);
+	}
+
+	StopI2C(adap);
+	IdleI2C(adap);
+	return 0;
+}
+
+static int
+i2c_write(struct i2c_platform_data *adap, unsigned char *buf,
+		     unsigned int len)
+{
+	int	i;
+	u32	data;
+
+	pr_debug("i2c_write\n");
+
+	i = 0;
+	while (i < len) {
+		data = buf[i];
+		if (MasterWriteI2C(adap, data))
+			return -EIO;
+		IdleI2C(adap);
+		if (pic32_bus_readl(adap->base + PIC32_I2CxSTAT) &
+		    I2CSTAT_ACKSTAT)
+			return -EIO;
+		i++;
+	}
+
+	StopI2C(adap);
+	IdleI2C(adap);
+	return 0;
+}
+
+static int
+platform_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
+{
+	struct i2c_platform_data *adap = i2c_adap->algo_data;
+	struct i2c_msg *p;
+	int i, err = 0;
+
+	pr_debug("platform_xfer\n");
+	for (i = 0; i < num; i++) {
+#define __BUFSIZE 80
+		int ii;
+		static char buf[__BUFSIZE];
+		char *b = buf;
+
+		p = &msgs[i];
+		b += sprintf(buf, " [%d bytes]", p->len);
+		if ((p->flags & I2C_M_RD) == 0) {
+			for (ii = 0; ii < p->len; ii++) {
+				if (b < &buf[__BUFSIZE-4]) {
+					b += sprintf(b, " %02x", p->buf[ii]);
+				} else {
+					strcat(b, "...");
+					break;
+				}
+			}
+		}
+		pr_debug("xfer%d: DevAddr: %04x Op:%s Data:%s\n", i, p->addr,
+			 (p->flags & I2C_M_RD) ? "Rd" : "Wr", buf);
+	}
+
+
+	for (i = 0; !err && i < num; i++) {
+		p = &msgs[i];
+		err = do_address(adap, p->addr, p->flags & I2C_M_RD);
+		if (err || !p->len)
+			continue;
+		if (p->flags & I2C_M_RD)
+			err = i2c_read(adap, p->buf, p->len);
+		else
+			err = i2c_write(adap, p->buf, p->len);
+	}
+
+	/* Return the number of messages processed, or the error code. */
+	if (err == 0)
+		err = num;
+
+	return err;
+}
+
+static u32
+platform_func(struct i2c_adapter *adap)
+{
+	pr_debug("platform_algo\n");
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm platform_algo = {
+	.master_xfer	= platform_xfer,
+	.functionality	= platform_func,
+};
+
+static void i2c_platform_setup(struct i2c_platform_data *priv)
+{
+	pr_debug("i2c_platform_setup\n");
+
+	pic32_bus_writel(500, priv->base + PIC32_I2CxBRG);
+	pic32_bus_writel(I2CCON_ON, priv->base + PIC32_I2CxCONCLR);
+	pic32_bus_writel(I2CCON_ON, priv->base + PIC32_I2CxCONSET);
+	pic32_bus_writel((I2CSTAT_BCL | I2CSTAT_IWCOL),
+		(priv->base + PIC32_I2CxSTATCLR));
+}
+
+static void i2c_platform_disable(struct i2c_platform_data *priv)
+{
+	pr_debug("i2c_platform_disable\n");
+}
+
+static int __devinit
+i2c_platform_probe(struct platform_device *pdev)
+{
+	struct i2c_platform_data *priv;
+	struct resource *r;
+	int ret;
+
+	pr_debug("i2c_platform_probe\n");
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!r) {
+		ret = -ENODEV;
+		goto out;
+	}
+
+	priv = kzalloc(sizeof(struct i2c_platform_data), GFP_KERNEL);
+	if (!priv) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	/* FIXME: need to allocate resource in PIC32 space */
+#if 0
+	priv->base = bus_request_region(r->start, resource_size(r),
+					  pdev->name);
+#else
+	priv->base = r->start;
+#endif
+	if (!priv->base) {
+		ret = -EBUSY;
+		goto out_mem;
+	}
+
+	priv->xfer_timeout = 200;
+	priv->ack_timeout = 200;
+	priv->ctl_timeout = 200;
+
+	priv->adap.nr = pdev->id;
+	priv->adap.algo = &platform_algo;
+	priv->adap.algo_data = priv;
+	priv->adap.dev.parent = &pdev->dev;
+	strlcpy(priv->adap.name, "PIC32 I2C", sizeof(priv->adap.name));
+
+	i2c_platform_setup(priv);
+
+	ret = i2c_add_numbered_adapter(&priv->adap);
+	if (ret == 0) {
+		platform_set_drvdata(pdev, priv);
+		return 0;
+	}
+
+	i2c_platform_disable(priv);
+
+out_mem:
+	kfree(priv);
+out:
+	return ret;
+}
+
+static int __devexit
+i2c_platform_remove(struct platform_device *pdev)
+{
+	struct i2c_platform_data *priv = platform_get_drvdata(pdev);
+
+	pr_debug("i2c_platform_remove\n");
+	platform_set_drvdata(pdev, NULL);
+	i2c_del_adapter(&priv->adap);
+	i2c_platform_disable(priv);
+	kfree(priv);
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int
+i2c_platform_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct i2c_platform_data *priv = platform_get_drvdata(pdev);
+
+	dev_dbg(&pdev->dev, "i2c_platform_disable\n");
+	i2c_platform_disable(priv);
+
+	return 0;
+}
+
+static int
+i2c_platform_resume(struct platform_device *pdev)
+{
+	struct i2c_platform_data *priv = platform_get_drvdata(pdev);
+
+	dev_dbg(&pdev->dev, "i2c_platform_setup\n");
+	i2c_platform_setup(priv);
+
+	return 0;
+}
+#else
+#define i2c_platform_suspend	NULL
+#define i2c_platform_resume	NULL
+#endif
+
+static struct platform_driver i2c_platform_driver = {
+	.driver = {
+		.name	= "i2c_pic32",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= i2c_platform_probe,
+	.remove		= __devexit_p(i2c_platform_remove),
+	.suspend	= i2c_platform_suspend,
+	.resume		= i2c_platform_resume,
+};
+
+static int __init
+i2c_platform_init(void)
+{
+	pr_debug("i2c_platform_init\n");
+	return platform_driver_register(&i2c_platform_driver);
+}
+
+static void __exit
+i2c_platform_exit(void)
+{
+	pr_debug("i2c_platform_exit\n");
+	platform_driver_unregister(&i2c_platform_driver);
+}
+
+MODULE_AUTHOR("Chris Dearman, MIPS Technologies INC.");
+MODULE_DESCRIPTION("PIC32 I2C driver");
+MODULE_LICENSE("GPL");
+
+module_init(i2c_platform_init);
+module_exit(i2c_platform_exit);