3 files changed, 80 insertions, 0 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index ade70017fd65..cfcb0d8d6f85 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1556,6 +1556,14 @@ config BL_SWITCHER
           transparently handle transition between a cluster of A15's
           and a cluster of A7's in a big.LITTLE system.
 
+config BL_SWITCHER_DUMMY_IF
+        tristate "Simple big.LITTLE switcher user interface"
+        depends on BL_SWITCHER && DEBUG_KERNEL
+        help
+          This is a simple and dummy char dev interface to control
+          the big.LITTLE switcher core code.  It is meant for
+          debugging purposes only.
+
 choice
         prompt "Memory split"
         default VMSPLIT_3G
diff --git a/arch/arm/common/Makefile b/arch/arm/common/Makefile
index 2586240d5a45..5c8584c4944d 100644
--- a/arch/arm/common/Makefile
+++ b/arch/arm/common/Makefile
@@ -18,3 +18,4 @@ AFLAGS_mcpm_head.o		:= -march=armv7-a
 AFLAGS_vlock.o                  := -march=armv7-a
 obj-$(CONFIG_TI_PRIV_EDMA)      += edma.o
 obj-$(CONFIG_BL_SWITCHER)       += bL_switcher.o
+obj-$(CONFIG_BL_SWITCHER_DUMMY_IF) += bL_switcher_dummy_if.o
diff --git a/arch/arm/common/bL_switcher_dummy_if.c b/arch/arm/common/bL_switcher_dummy_if.c
new file mode 100644
index 000000000000..3f47f1203c6b
--- /dev/null
+++ b/arch/arm/common/bL_switcher_dummy_if.c
@@ -0,0 +1,71 @@
+/*
+ * arch/arm/common/bL_switcher_dummy_if.c -- b.L switcher dummy interface
+ *
+ * Created by:  Nicolas Pitre, November 2012
+ * Copyright:   (C) 2012-2013  Linaro Limited
+ *
+ * Dummy interface to user space for debugging purpose only.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <asm/uaccess.h>
+#include <asm/bL_switcher.h>
+
+static ssize_t bL_switcher_write(struct file *file, const char __user *buf,
+                        size_t len, loff_t *pos)
+{
+        unsigned char val[3];
+        unsigned int cpu, cluster;
+        int ret;
+
+        pr_debug("%s\n", __func__);
+
+        if (len < 3)
+                return -EINVAL;
+
+        if (copy_from_user(val, buf, 3))
+                return -EFAULT;
+
+        /* format: <cpu#>,<cluster#> */
+        if (val[0] < '0' || val[0] > '9' ||
+            val[1] != ',' ||
+            val[2] < '0' || val[2] > '1')
+                return -EINVAL;
+
+        cpu = val[0] - '0';
+        cluster = val[2] - '0';
+        ret = bL_switch_request(cpu, cluster);
+
+        return ret ? : len;
+}
+
+static const struct file_operations bL_switcher_fops = {
+        .write          = bL_switcher_write,
+        .owner  = THIS_MODULE,
+};
+
+static struct miscdevice bL_switcher_device = {
+        MISC_DYNAMIC_MINOR,
+        "b.L_switcher",
+        &bL_switcher_fops
+};
+
+static int __init bL_switcher_dummy_if_init(void)
+{
+        return misc_register(&bL_switcher_device);
+}
+
+static void __exit bL_switcher_dummy_if_exit(void)
+{
+        misc_deregister(&bL_switcher_device);
+}
+
+module_init(bL_switcher_dummy_if_init);
+module_exit(bL_switcher_dummy_if_exit);