tegra: add I2C adapter-class driver

Driver implementation uses NvRm, NvDdk and NvOdm APIs to implement standard I2C
bus interface.

Change-Id: I29fbd39bd7fae95d70f1a1b9b552e34cc045371c

4 files changed, 309 insertions, 0 deletions

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 7f95905bbb9d..0602f0b01689 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -180,6 +180,14 @@ config I2C_SIS630
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-sis630.
 
+config I2C_TEGRA
+	boolean "NVIDIA Tegra internal I2C controller"
+	depends on ARCH_TEGRA
+	help
+	  If you say yes to this option, support will be included for the
+	  I2C controller embedded in NVIDIA Tegra SOCs
+
+
 config I2C_SIS96X
 	tristate "SiS 96x"
 	depends on PCI
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 0c2c4b26cdf1..104b63198dee 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -47,6 +47,7 @@ obj-$(CONFIG_I2C_SH7760)	+= i2c-sh7760.o
 obj-$(CONFIG_I2C_SH_MOBILE)	+= i2c-sh_mobile.o
 obj-$(CONFIG_I2C_SIMTEC)	+= i2c-simtec.o
 obj-$(CONFIG_I2C_VERSATILE)	+= i2c-versatile.o
+obj-$(CONFIG_I2C_TEGRA)		+= i2c-tegra.o
 
 # External I2C/SMBus adapter drivers
 obj-$(CONFIG_I2C_PARPORT)	+= i2c-parport.o
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
new file mode 100644
index 000000000000..723b8e4a797d
--- /dev/null
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -0,0 +1,290 @@
+/*
+ * drivers/i2c/busses/i2c-tegra.c
+ *
+ * I2C bus driver for internal I2C controllers in NVIDIA Tegra SoCs
+ *
+ * Copyright (C) 2009 NVIDIA Corporation
+ *
+ * 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/tegra_devices.h>
+#include <asm/uaccess.h>
+
+#include <mach/nvrm_linux.h>
+#include <nvrm_module.h>
+#include <nvos.h>
+#include <nvodm_query_discovery.h>
+
+#define I2C_SMBUS_TRASNSPORT_GUID NV_ODM_GUID('I','2','c','S','m','B','u','s')
+
+struct tegra_i2c_dev
+{
+	struct device		*dev;
+	struct i2c_adapter	adapter;
+	NvRmI2cHandle		I2cHandle;
+	int			clock_in_khz;
+	NvOdmI2cPinMap		pin_map;
+};
+
+static int tegra_i2c_xfer(struct i2c_adapter *adap,
+	struct i2c_msg msgs[], int num)
+{
+	struct tegra_i2c_dev  *dev = i2c_get_adapdata(adap);
+	NvRmI2cTransactionInfo *tInfo=NULL;
+	NvU32 i;
+	NvU32 len=0;
+	int err = 0;
+	int nverror = NvSuccess;
+	NvU8 *tempBuffer,*buffer=NULL;
+
+	tInfo = kzalloc(sizeof(NvRmI2cTransactionInfo)*num,GFP_KERNEL);
+	if(!tInfo) {
+		printk(KERN_ERR "tegra_i2c_xfer: Could not allocate memory\n");
+		err = -ENOMEM;
+		goto end;
+	}
+
+	for(i = 0 ; i < num ; i++) {
+		len += msgs[i].len;
+	}
+
+	buffer = kzalloc(len,GFP_KERNEL);
+	if(!buffer) {
+		printk(KERN_ERR "tegra_i2c_xfer: Could not allocate memory\n");
+		err = -ENOMEM;
+		goto end;
+	}
+
+	/*
+	 * NvRmI2cTransactions accepts all the messages at once. We can not
+	 * send 1 message at a time. Hence clubbing all messages and
+	 * representing them in a form that NvRmI2cTransactions understands
+	 * */
+
+	tempBuffer = buffer;
+
+	for (i = 0 ;  i < num ; i++) {
+		if (msgs[i].flags & I2C_M_NOSTART) {
+			tInfo[i].Flags |= NVRM_I2C_NOSTOP;
+		}
+		if (msgs[i].flags & I2C_M_IGNORE_NAK) {
+			tInfo[i].Flags |= NVRM_I2C_NOACK;
+		}
+		if (msgs[i].flags & I2C_M_RD) {
+			tInfo[i].Flags |= NVRM_I2C_READ;
+		}
+		else {
+			tInfo[i].Flags |= NVRM_I2C_WRITE;
+			memcpy(tempBuffer,msgs[i].buf,msgs[i].len);
+		}
+		tempBuffer += msgs[i].len;
+		tInfo[i].NumBytes = msgs[i].len;
+		tInfo[i].Address = msgs[i].addr << 1;
+		tInfo[i].Is10BitAddress =  (NvBool)(msgs[i].flags &  I2C_M_TEN);
+	}
+
+	nverror = NvRmI2cTransaction(dev->I2cHandle, dev->pin_map, 1000,
+			dev->clock_in_khz, buffer, len, tInfo, num);
+
+	if (nverror != NvSuccess) {
+		switch (nverror) {
+		case NvError_I2cDeviceNotFound:
+			printk(KERN_ERR "NvRmI2cTransaction failed: No I2C "
+					"device claimed the address 0x%x on "
+					"adapter %d\n", msgs[i].addr,adap->nr);
+			err = -ENXIO;
+			break;
+		case NvError_I2cReadFailed:
+			printk(KERN_ERR "NvRmI2c Read failed %x\n", err);
+			err = -EIO;
+			break;
+		case NvError_I2cWriteFailed:
+			printk(KERN_ERR "NvRmI2c Write failed %x\n", err);
+			err = -EIO;
+			break;
+		case NvError_Timeout:
+			printk(KERN_ERR "NvRmI2c Timeout %x\n", err);
+			err = -ETIMEDOUT;
+			break;
+		default:
+			printk(KERN_ERR "NvRmI2c Transaction Error %x\n",err);
+			err = -EIO;
+			break;
+		}
+		goto end;
+	}
+
+	tempBuffer = buffer;
+
+	for (i = 0 ; i < num ; i++) {
+		if (tInfo[i].Flags & NVRM_I2C_READ) {
+			memcpy(msgs[i].buf,tempBuffer,tInfo[i].NumBytes);
+		}
+		tempBuffer += tInfo[i].NumBytes;
+	}
+
+end:
+	if(tInfo != NULL)
+		kfree(tInfo);
+
+	if(buffer != NULL)
+		kfree(buffer);
+
+	if (!err)
+		return num;
+	else
+		return err;
+}
+
+static u32 tegra_i2c_func(struct i2c_adapter *adap)
+{
+	/* FIXME: For now keep it simple and don't support protocol mangling
+	   features */
+	return I2C_FUNC_I2C;
+}
+
+static const struct i2c_algorithm tegra_i2c_algo = {
+	.master_xfer	= tegra_i2c_xfer,
+	.functionality	= tegra_i2c_func,
+};
+
+static int tegra_i2c_probe(struct platform_device *pdev)
+{
+	struct tegra_i2c_dev *dev;
+	struct tegra_i2c_platform_data *pdata = pdev->dev.platform_data;
+	int ret;
+	NvError err;
+	const NvOdmPeripheralConnectivity *pConn = NULL;
+	const NvOdmIoAddress *addr_list;
+	int i = 0;
+
+	printk(KERN_INFO "tegra_i2c_probe\n");
+
+	if (pdata == NULL)
+		return -ENODEV;
+
+	// Check if the I2C instance is dedicated for NvEc communication.
+	// If yes, then don't allow it to register as platform driver.
+	pConn = NvOdmPeripheralGetGuid(I2C_SMBUS_TRASNSPORT_GUID);
+	if (pConn) {
+		const NvOdmIoAddress *addr_list = pConn->AddressList;
+		for (i = 0; i < pConn->NumAddress; i++, addr_list++) {
+			if (addr_list->Interface == NvOdmIoModule_I2c) &&
+				addr_list->Instance == pData->Instance) {
+				return -ENODEV;
+			}
+		}
+	}
+
+	dev = kzalloc(sizeof(struct tegra_i2c_dev), GFP_KERNEL);
+	if (!dev)
+	{
+		ret = -ENOMEM;
+		return ret;
+	}
+
+	err = NvRmI2cOpen(s_hRmGlobal, pdata->IoModuleID,
+		pdata->Instance, &dev->I2cHandle);
+	if (err)
+	{
+		ret = -ENODEV;
+		printk("Failed to open NvRmI2cOpen - returned %d\n", err);
+		goto err_rmapi_failed;
+	}
+	dev->clock_in_khz = pdata->ClockInKHz;
+	dev->pin_map = pdata->PinMuxConfig;
+
+	dev->dev = &pdev->dev;
+	platform_set_drvdata(pdev, dev);
+
+	i2c_set_adapdata(&dev->adapter, dev);
+	dev->adapter.algo = &tegra_i2c_algo;
+	strncpy(dev->adapter.name, "Tegra I2C adapter",
+		sizeof(dev->adapter.name));
+
+	dev->adapter.nr = pdev->id;
+	ret = i2c_add_numbered_adapter(&dev->adapter);
+	if (ret)
+	{
+		dev_err(&pdev->dev, "i2c_add_adapter failed\n");
+		goto err_i2c_add_adapter_failed;
+	}
+
+	return 0;
+
+err_rmapi_failed:
+err_i2c_add_adapter_failed:
+	kfree(dev);
+	return ret;
+}
+
+static int
+tegra_i2c_remove(struct platform_device *pdev)
+{
+	struct tegra_i2c_dev *dev = platform_get_drvdata(pdev);
+
+	NvRmI2cClose(dev->I2cHandle);
+	platform_set_drvdata(pdev, NULL);
+	i2c_del_adapter(&dev->adapter);
+	kfree(dev);
+	return 0;
+}
+
+static int tegra_i2c_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	/* FIXME to be implemented */
+	return 0;
+}
+
+static int tegra_i2c_resume(struct platform_device *pdev)
+{
+	/* FIXME to be implemented */
+	return 0;
+}
+
+static struct platform_driver tegra_i2c_driver = {
+	.probe   = tegra_i2c_probe,
+	.remove  = tegra_i2c_remove,
+	.suspend = tegra_i2c_suspend,
+	.resume  = tegra_i2c_resume,
+	.driver  =
+	{
+		.name  = "tegra_i2c",
+		.owner = THIS_MODULE,
+	},
+};
+
+/* I2C may be needed to bring up other drivers */
+static int __init
+tegra_i2c_init_driver(void)
+{
+	return platform_driver_register(&tegra_i2c_driver);
+}
+module_init(tegra_i2c_init_driver);
+
+static void __exit tegra_i2c_exit_driver(void)
+{
+	platform_driver_unregister(&tegra_i2c_driver);
+}
+module_exit(tegra_i2c_exit_driver);
diff --git a/include/linux/tegra_devices.h b/include/linux/tegra_devices.h
index d3fd49fa0684..a890e0276a79 100644
--- a/include/linux/tegra_devices.h
+++ b/include/linux/tegra_devices.h
@@ -27,7 +27,9 @@
 #include "nvrm_gpio.h"
 #include "nvddk_usbphy.h"
 #include "nvodm_query.h"
+#include "nvodm_query_pinmux.h"
 
+/* Platform data for EHCI HCD driver */
 struct tegra_hcd_platform_data {
 	NvU32			instance;
 	NvRmGpioPinHandle	hGpioIDpin;
@@ -42,4 +44,12 @@ struct tegra_hcd_platform_data {
 	NvDdkUsbPhyHandle	hUsbPhy;
 };
 
+/* Platfrom data for I2C bus driver */
+struct tegra_i2c_platform_data {
+	NvU32		IoModuleID;
+	NvU32		Instance;
+	NvU32		ClockInKHz;
+	NvOdmI2cPinMap	PinMuxConfig;
+};
+
 #endif