From 2be12549c900303c418fcbb7044979e190fd4e7e Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Thu, 12 Apr 2012 03:04:28 -0400 Subject: ARM: bL_switcher: add a simple /dev user interface for debugging purposes Only the basic to aid debugging. Usage: echo , > /dev/b.L_switcher where is between 0 and 3, and is 0 for the A15 cluster and 1 for the A7 cluster. Signed-off-by: nicolas Pitre --- arch/arm/common/bL_switcher_dummy_if.c | 71 ++++++++++++++++++++++++++++++++++ 1 file changed, 71 insertions(+) create mode 100644 arch/arm/common/bL_switcher_dummy_if.c (limited to 'arch/arm/common/bL_switcher_dummy_if.c') 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 00000000000..5e2dd197e72 --- /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 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 +#include +#include +#include +#include +#include + +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: , */ + if (val[0] < '0' || val[0] > '4' || + 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); -- cgit v1.2.3