[PATCH 1/2] ARM.imx51 Freescale: 00106026-5 Add mxc IIM driver support

[Brad Figg]

Add mxc IIM driver support.

Signed-off-by: Liu Ying <b17645 at freescale.com>
Signed-off-by: Brad Figg <brad.figg at canonical.com>
---
 drivers/char/Kconfig   |    6 ++
 drivers/char/Makefile  |    1 +
 drivers/char/mxc_iim.c |  166 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 173 insertions(+), 0 deletions(-)
 create mode 100644 drivers/char/mxc_iim.c

diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index 782f4a5..c1f9d10 100644
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -424,6 +424,12 @@ config IMX_SIM
 	---help---
          Say Y to enable the SIM driver support.
 
+config MXC_IIM
+	tristate "MXC IIM device driver"
+	depends on ARCH_MXC
+	help
+	  Support for access to MXC IIM device, most people should say N here.
+
 source "drivers/serial/Kconfig"
 
 config UNIX98_PTYS
diff --git a/drivers/char/Makefile b/drivers/char/Makefile
index e4ae86e..bbd7913 100644
--- a/drivers/char/Makefile
+++ b/drivers/char/Makefile
@@ -9,6 +9,7 @@ FONTMAPFILE = cp437.uni
 
 obj-y	 += mem.o random.o tty_io.o n_tty.o tty_ioctl.o tty_ldisc.o tty_buffer.o tty_port.o
 
+obj-$(CONFIG_MXC_IIM)		+= mxc_iim.o
 obj-$(CONFIG_LEGACY_PTYS)	+= pty.o
 obj-$(CONFIG_UNIX98_PTYS)	+= pty.o
 obj-$(CONFIG_IMX_SIM) 		+= imx_sim.o
diff --git a/drivers/char/mxc_iim.c b/drivers/char/mxc_iim.c
new file mode 100644
index 0000000..c8956e7
--- /dev/null
+++ b/drivers/char/mxc_iim.c
@@ -0,0 +1,166 @@
+/*
+ * Copyright 2009 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/clk.h>
+#include <linux/miscdevice.h>
+
+static unsigned long iim_reg_base, iim_reg_end, iim_reg_size;
+static struct clk *iim_clk;
+static struct device *iim_dev;
+
+/*!
+ * MXC IIM interface - memory map function
+ *
+ * @param file	     struct file *
+ * @param vma	     structure vm_area_struct *
+ *
+ * @return	     Return 0 on success or negative error code on error
+ */
+static int mxc_iim_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	size_t size = vma->vm_end - vma->vm_start;
+
+	/* Check the physical addresses which can be mapped */
+	if ((vma->vm_pgoff != 0) || (size > iim_reg_size))
+		return -EINVAL;
+
+	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_base >> PAGE_SHIFT,
+			    size,
+			    vma->vm_page_prot))
+		return -EAGAIN;
+
+	return 0;
+}
+
+/*!
+ * MXC 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 mxc_iim_open(struct inode *inode, struct file *filp)
+{
+	iim_clk = clk_get(NULL, "iim_clk");
+	if (IS_ERR(iim_clk)) {
+		dev_err(iim_dev, "No IIM clock defined\n");
+		return -ENODEV;
+	}
+	clk_enable(iim_clk);
+
+	return 0;
+}
+
+/*!
+ * MXC 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 mxc_iim_release(struct inode *inode, struct file *filp)
+{
+	clk_disable(iim_clk);
+	clk_put(iim_clk);
+	return 0;
+}
+
+static const struct file_operations mxc_iim_fops = {
+	.mmap = mxc_iim_mmap,
+	.open = mxc_iim_open,
+	.release = mxc_iim_release,
+};
+
+static struct miscdevice mxc_iim_miscdev = {
+	.minor = MISC_DYNAMIC_MINOR,
+	.name = "mxc_iim",
+	.fops = &mxc_iim_fops,
+};
+
+/*!
+ * This function is called by the driver framework to get iim base/end address
+ * and register iim misc device.
+ *
+ * @param	dev	The device structure for IIM passed in by the driver
+ *			framework.
+ *
+ * @return      Returns 0 on success or negative error code on error
+ */
+static int mxc_iim_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 IIM resource\n");
+		return -ENODEV;
+	}
+
+	iim_reg_base = res->start;
+	iim_reg_end = res->end;
+	iim_reg_size = iim_reg_end - iim_reg_base + 1;
+
+	ret = misc_register(&mxc_iim_miscdev);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int mxc_iim_remove(struct platform_device *pdev)
+{
+	misc_deregister(&mxc_iim_miscdev);
+	return 0;
+}
+
+static struct platform_driver mxc_iim_driver = {
+	.driver = {
+		   .owner = THIS_MODULE,
+		   .name = "mxc_iim",
+		   },
+	.probe = mxc_iim_probe,
+	.remove = mxc_iim_remove,
+};
+
+static int __init mxc_iim_dev_init(void)
+{
+	return platform_driver_register(&mxc_iim_driver);
+}
+
+static void __exit mxc_iim_dev_cleanup(void)
+{
+	platform_driver_unregister(&mxc_iim_driver);
+}
+
+module_init(mxc_iim_dev_init);
+module_exit(mxc_iim_dev_cleanup);
+
+MODULE_AUTHOR("Freescale Semiconductor, Inc.");
+MODULE_DESCRIPTION("MXC IIM driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(MISC_DYNAMIC_MINOR);
-- 
1.6.0.4