7segled.c

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/*
 * 7 Segment LED routines
 * Based on RBTX49xx patch from CELF patch archive.
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * (C) Copyright TOSHIBA CORPORATION 2005-2007
 * All Rights Reserved.
 */
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/map_to_7segment.h>
#include <asm/txx9/generic.h>

static unsigned int tx_7segled_num;
static void (*tx_7segled_putc)(unsigned int pos, unsigned char val);

void __init txx9_7segled_init(unsigned int num,
                  void (*putc)(unsigned int pos, unsigned char val))
{
    tx_7segled_num = num;
    tx_7segled_putc = putc;
}

static SEG7_CONVERSION_MAP(txx9_seg7map, MAP_ASCII7SEG_ALPHANUM_LC);

int txx9_7segled_putc(unsigned int pos, char c)
{
    if (pos >= tx_7segled_num)
        return -EINVAL;
    c = map_to_seg7(&txx9_seg7map, c);
    if (c < 0)
        return c;
    tx_7segled_putc(pos, c);
    return 0;
}

static ssize_t ascii_store(struct device *dev,
               struct device_attribute *attr,
               const char *buf, size_t size)
{
    unsigned int ch = dev->id;
    txx9_7segled_putc(ch, buf[0]);
    return size;
}

static ssize_t raw_store(struct device *dev,
             struct device_attribute *attr,
             const char *buf, size_t size)
{
    unsigned int ch = dev->id;
    tx_7segled_putc(ch, buf[0]);
    return size;
}

static DEVICE_ATTR(ascii, 0200, NULL, ascii_store);
static DEVICE_ATTR(raw, 0200, NULL, raw_store);

static ssize_t map_seg7_show(struct device *dev,
                 struct device_attribute *attr,
                 char *buf)
{
    memcpy(buf, &txx9_seg7map, sizeof(txx9_seg7map));
    return sizeof(txx9_seg7map);
}

static ssize_t map_seg7_store(struct device *dev,
                  struct device_attribute *attr,
                  const char *buf, size_t size)
{
    if (size != sizeof(txx9_seg7map))
        return -EINVAL;
    memcpy(&txx9_seg7map, buf, size);
    return size;
}

static DEVICE_ATTR(map_seg7, 0600, map_seg7_show, map_seg7_store);

static struct bus_type tx_7segled_subsys = {
    .name       = "7segled",
    .dev_name   = "7segled",
};

static int __init tx_7segled_init_sysfs(void)
{
    int error, i;
    if (!tx_7segled_num)
        return -ENODEV;
    error = subsys_system_register(&tx_7segled_subsys, NULL);
    if (error)
        return error;
    error = device_create_file(tx_7segled_subsys.dev_root, &dev_attr_map_seg7);
    if (error)
        return error;
    for (i = 0; i < tx_7segled_num; i++) {
        struct device *dev;
        dev = kzalloc(sizeof(*dev), GFP_KERNEL);
        if (!dev) {
            error = -ENODEV;
            break;
        }
        dev->id = i;
        dev->bus = &tx_7segled_subsys;
        error = device_register(dev);
        if (!error) {
            device_create_file(dev, &dev_attr_ascii);
            device_create_file(dev, &dev_attr_raw);
        }
    }
    return error;
}

device_initcall(tx_7segled_init_sysfs);