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-rw-r--r--arch/v850/kernel/rte_cb_leds.c137
1 files changed, 0 insertions, 137 deletions
diff --git a/arch/v850/kernel/rte_cb_leds.c b/arch/v850/kernel/rte_cb_leds.c
deleted file mode 100644
index aa47ab1dcd87..000000000000
--- a/arch/v850/kernel/rte_cb_leds.c
+++ /dev/null
@@ -1,137 +0,0 @@
1/*
2 * include/asm-v850/rte_cb_leds.c -- Midas lab RTE-CB board LED device support
3 *
4 * Copyright (C) 2002,03 NEC Electronics Corporation
5 * Copyright (C) 2002,03 Miles Bader <miles@gnu.org>
6 *
7 * This file is subject to the terms and conditions of the GNU General
8 * Public License. See the file COPYING in the main directory of this
9 * archive for more details.
10 *
11 * Written by Miles Bader <miles@gnu.org>
12 */
13
14#include <linux/init.h>
15#include <linux/spinlock.h>
16#include <linux/fs.h>
17#include <linux/miscdevice.h>
18
19#include <asm/uaccess.h>
20
21#define LEDS_MINOR 169 /* Minor device number, using misc major. */
22
23/* The actual LED hardware is write-only, so we hold the contents here too. */
24static unsigned char leds_image[LED_NUM_DIGITS] = { 0 };
25
26/* Spinlock protecting the above leds. */
27static DEFINE_SPINLOCK(leds_lock);
28
29/* Common body of LED read/write functions, checks POS and LEN for
30 correctness, declares a variable using IMG_DECL, initialized pointing at
31 the POS position in the LED image buffer, and and iterates COPY_EXPR
32 until BUF is equal to the last buffer position; finally, sets LEN to be
33 the amount actually copied. IMG should be a variable declaration
34 (without an initializer or a terminating semicolon); POS, BUF, and LEN
35 should all be simple variables. */
36#define DO_LED_COPY(img_decl, pos, buf, len, copy_expr) \
37do { \
38 if (pos > LED_NUM_DIGITS) \
39 len = 0; \
40 else { \
41 if (pos + len > LED_NUM_DIGITS) \
42 len = LED_NUM_DIGITS - pos; \
43 \
44 if (len > 0) { \
45 unsigned long _flags; \
46 const char *_end = buf + len; \
47 img_decl = &leds_image[pos]; \
48 \
49 spin_lock_irqsave (leds_lock, _flags); \
50 do \
51 (copy_expr); \
52 while (buf != _end); \
53 spin_unlock_irqrestore (leds_lock, _flags); \
54 } \
55 } \
56} while (0)
57
58/* Read LEN bytes from LEDs at position POS, into BUF.
59 Returns actual amount read. */
60unsigned read_leds (unsigned pos, char *buf, unsigned len)
61{
62 DO_LED_COPY (const char *img, pos, buf, len, *buf++ = *img++);
63 return len;
64}
65
66/* Write LEN bytes to LEDs at position POS, from BUF.
67 Returns actual amount written. */
68unsigned write_leds (unsigned pos, const char *buf, unsigned len)
69{
70 /* We write the actual LED values backwards, because
71 increasing memory addresses reflect LEDs right-to-left. */
72 volatile char *led = &LED (LED_NUM_DIGITS - pos - 1);
73 /* We invert the value written to the hardware, because 1 = off,
74 and 0 = on. */
75 DO_LED_COPY (char *img, pos, buf, len,
76 *led-- = 0xFF ^ (*img++ = *buf++));
77 return len;
78}
79
80
81/* Device functions. */
82
83static ssize_t leds_dev_read (struct file *file, char *buf, size_t len,
84 loff_t *pos)
85{
86 char temp_buf[LED_NUM_DIGITS];
87 len = read_leds (*pos, temp_buf, len);
88 if (copy_to_user (buf, temp_buf, len))
89 return -EFAULT;
90 *pos += len;
91 return len;
92}
93
94static ssize_t leds_dev_write (struct file *file, const char *buf, size_t len,
95 loff_t *pos)
96{
97 char temp_buf[LED_NUM_DIGITS];
98 if (copy_from_user (temp_buf, buf, min_t(size_t, len, LED_NUM_DIGITS)))
99 return -EFAULT;
100 len = write_leds (*pos, temp_buf, len);
101 *pos += len;
102 return len;
103}
104
105static loff_t leds_dev_lseek (struct file *file, loff_t offs, int whence)
106{
107 if (whence == 1)
108 offs += file->f_pos; /* relative */
109 else if (whence == 2)
110 offs += LED_NUM_DIGITS; /* end-relative */
111
112 if (offs < 0 || offs > LED_NUM_DIGITS)
113 return -EINVAL;
114
115 file->f_pos = offs;
116
117 return 0;
118}
119
120static const struct file_operations leds_fops = {
121 .read = leds_dev_read,
122 .write = leds_dev_write,
123 .llseek = leds_dev_lseek
124};
125
126static struct miscdevice leds_miscdev = {
127 .name = "leds",
128 .minor = LEDS_MINOR,
129 .fops = &leds_fops
130};
131
132int __init leds_dev_init (void)
133{
134 return misc_register (&leds_miscdev);
135}
136
137__initcall (leds_dev_init);
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