ENGR00154889-2: Add virtual iim driver

Add virtual iim driver.
This driver will be used by MM team.

Signed-off-by: Terry Lv <r65388@freescale.com>
(cherry picked from commit 6637e480585112bb310fcbd7ccd1cbf1d67cf9ff)
Signed-off-by: Robin Gong <b38343@freescale.com>

3 files changed, 182 insertions, 0 deletions

diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index 15a6d56c95b9..926b469fd3bd 100644
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -620,5 +620,11 @@ config TILE_SROM
 	  device appear much like a simple EEPROM, and knows
 	  how to partition a single ROM for multiple purposes.
 
+config MXS_VIIM
+	tristate "MXS Virtual IIM device driver"
+	depends on (ARCH_MX50 || ARCH_MX6)
+	help
+	  Support for access to MXS Virtual IIM device, most people should say N here.
+
 endmenu
 
diff --git a/drivers/char/Makefile b/drivers/char/Makefile
index 53f7ea5506b7..953be8dba511 100644
--- a/drivers/char/Makefile
+++ b/drivers/char/Makefile
@@ -58,6 +58,7 @@ obj-$(CONFIG_HANGCHECK_TIMER)	+= hangcheck-timer.o
 obj-$(CONFIG_TCG_TPM)		+= tpm/
 
 obj-$(CONFIG_PS3_FLASH)		+= ps3flash.o
+obj-$(CONFIG_MXS_VIIM)		+= mxs_viim.o
 
 obj-$(CONFIG_JS_RTC)		+= js-rtc.o
 js-rtc-y = rtc.o
diff --git a/drivers/char/mxs_viim.c b/drivers/char/mxs_viim.c
new file mode 100644
index 000000000000..9384b84cd77b
--- /dev/null
+++ b/drivers/char/mxs_viim.c
@@ -0,0 +1,175 @@
+/*
+ * Copyright (C) 2009-2011, 2014 Freescale Semiconductor, Inc. All Rights Reserved.
+ */
+
+/*
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/mm.h>
+#include <linux/miscdevice.h>
+
+static unsigned long iim_reg_base0, iim_reg_end0, iim_reg_size0;
+static unsigned long iim_reg_base1, iim_reg_end1, iim_reg_size1;
+static struct device *iim_dev;
+
+/*!
+ * MXS Virtual IIM interface - memory map function
+ * This function maps one page size VIIM registers from VIIM base address0
+ * if the size of the required virtual memory space is less than or equal to
+ * one page size, otherwise this function will also map one page size VIIM
+ * registers from VIIM base address1.
+ *
+ * @param file	     struct file *
+ * @param vma	     structure vm_area_struct *
+ *
+ * @return	     Return 0 on success or negative error code on error
+ */
+static int mxs_viim_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	size_t size = vma->vm_end - vma->vm_start;
+
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+	/* Remap-pfn-range will mark the range VM_IO and VM_RESERVED */
+	if (remap_pfn_range(vma,
+			    vma->vm_start,
+			    iim_reg_base0 >> PAGE_SHIFT,
+			    iim_reg_size0,
+			    vma->vm_page_prot))
+		return -EAGAIN;
+
+	if (size > iim_reg_size0) {
+		if (remap_pfn_range(vma,
+				    vma->vm_start + iim_reg_size0,
+				    iim_reg_base1 >> PAGE_SHIFT,
+				    iim_reg_size1,
+				    vma->vm_page_prot))
+			return -EAGAIN;
+	}
+
+	return 0;
+}
+
+/*!
+ * MXS Virtual IIM interface - open function
+ *
+ * @param inode	     struct inode *
+ * @param filp	     struct file *
+ *
+ * @return	     Return 0 on success or negative error code on error
+ */
+static int mxs_viim_open(struct inode *inode, struct file *filp)
+{
+	return 0;
+}
+
+/*!
+ * MXS Virtual IIM interface - release function
+ *
+ * @param inode	     struct inode *
+ * @param filp	     struct file *
+ *
+ * @return	     Return 0 on success or negative error code on error
+ */
+static int mxs_viim_release(struct inode *inode, struct file *filp)
+{
+	return 0;
+}
+
+static const struct file_operations mxs_viim_fops = {
+	.mmap = mxs_viim_mmap,
+	.open = mxs_viim_open,
+	.release = mxs_viim_release,
+};
+
+static struct miscdevice mxs_viim_miscdev = {
+	.minor = MISC_DYNAMIC_MINOR,
+	.name = "mxs_viim",
+	.fops = &mxs_viim_fops,
+};
+
+/*!
+ * This function is called by the driver framework to get virtual iim base/end
+ * address and register iim misc device.
+ *
+ * @param	dev	The device structure for Virtual IIM passed in by the
+ *			driver framework.
+ *
+ * @return      Returns 0 on success or negative error code on error
+ */
+static int mxs_viim_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	int ret;
+
+	iim_dev = &pdev->dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (IS_ERR(res)) {
+		dev_err(iim_dev, "Unable to get Virtual IIM resource 0\n");
+		return -ENODEV;
+	}
+
+	iim_reg_base0 = res->start;
+	iim_reg_end0 = res->end;
+	iim_reg_size0 = iim_reg_end0 - iim_reg_base0 + 1;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (IS_ERR(res)) {
+		dev_err(iim_dev, "Unable to get Virtual IIM resource 1\n");
+		return -ENODEV;
+	}
+
+	iim_reg_base1 = res->start;
+	iim_reg_end1 = res->end;
+	iim_reg_size1 = iim_reg_end1 - iim_reg_base1 + 1;
+
+	ret = misc_register(&mxs_viim_miscdev);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int mxs_viim_remove(struct platform_device *pdev)
+{
+	misc_deregister(&mxs_viim_miscdev);
+	return 0;
+}
+
+static struct platform_driver mxs_viim_driver = {
+	.driver = {
+		   .owner = THIS_MODULE,
+		   .name = "imx_viim",
+		   },
+	.probe = mxs_viim_probe,
+	.remove = mxs_viim_remove,
+};
+
+static int __init mxs_viim_dev_init(void)
+{
+	return platform_driver_register(&mxs_viim_driver);
+}
+
+static void __exit mxs_viim_dev_cleanup(void)
+{
+	platform_driver_unregister(&mxs_viim_driver);
+}
+
+module_init(mxs_viim_dev_init);
+module_exit(mxs_viim_dev_cleanup);
+
+MODULE_AUTHOR("Freescale Semiconductor, Inc.");
+MODULE_DESCRIPTION("IMX Virtual IIM driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(MISC_DYNAMIC_MINOR);