118 lines
2.6 KiB
C
118 lines
2.6 KiB
C
/*
|
|
* OF helpers for the I2C API
|
|
*
|
|
* Copyright (c) 2008 Jochen Friedrich <jochen@scram.de>
|
|
*
|
|
* Based on a previous patch from Jon Smirl <jonsmirl@gmail.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*/
|
|
|
|
#include <linux/i2c.h>
|
|
#include <linux/of.h>
|
|
#include <linux/module.h>
|
|
|
|
struct i2c_driver_device {
|
|
char *of_device;
|
|
char *i2c_type;
|
|
};
|
|
|
|
static struct i2c_driver_device i2c_devices[] = {
|
|
};
|
|
|
|
static int of_find_i2c_driver(struct device_node *node,
|
|
struct i2c_board_info *info)
|
|
{
|
|
int i, cplen;
|
|
const char *compatible;
|
|
const char *p;
|
|
|
|
/* 1. search for exception list entry */
|
|
for (i = 0; i < ARRAY_SIZE(i2c_devices); i++) {
|
|
if (!of_device_is_compatible(node, i2c_devices[i].of_device))
|
|
continue;
|
|
if (strlcpy(info->type, i2c_devices[i].i2c_type,
|
|
I2C_NAME_SIZE) >= I2C_NAME_SIZE)
|
|
return -ENOMEM;
|
|
|
|
return 0;
|
|
}
|
|
|
|
compatible = of_get_property(node, "compatible", &cplen);
|
|
if (!compatible)
|
|
return -ENODEV;
|
|
|
|
/* 2. search for linux,<i2c-type> entry */
|
|
p = compatible;
|
|
while (cplen > 0) {
|
|
if (!strncmp(p, "linux,", 6)) {
|
|
p += 6;
|
|
if (strlcpy(info->type, p,
|
|
I2C_NAME_SIZE) >= I2C_NAME_SIZE)
|
|
return -ENOMEM;
|
|
return 0;
|
|
}
|
|
|
|
i = strlen(p) + 1;
|
|
p += i;
|
|
cplen -= i;
|
|
}
|
|
|
|
/* 3. take fist compatible entry and strip manufacturer */
|
|
p = strchr(compatible, ',');
|
|
if (!p)
|
|
return -ENODEV;
|
|
p++;
|
|
if (strlcpy(info->type, p, I2C_NAME_SIZE) >= I2C_NAME_SIZE)
|
|
return -ENOMEM;
|
|
return 0;
|
|
}
|
|
|
|
void of_register_i2c_devices(struct i2c_adapter *adap,
|
|
struct device_node *adap_node)
|
|
{
|
|
void *result;
|
|
struct device_node *node;
|
|
|
|
for_each_child_of_node(adap_node, node) {
|
|
struct i2c_board_info info = {};
|
|
const u32 *addr;
|
|
int len;
|
|
|
|
addr = of_get_property(node, "reg", &len);
|
|
if (!addr || len < sizeof(int) || *addr > (1 << 10) - 1) {
|
|
printk(KERN_ERR
|
|
"of-i2c: invalid i2c device entry\n");
|
|
continue;
|
|
}
|
|
|
|
info.irq = irq_of_parse_and_map(node, 0);
|
|
if (info.irq == NO_IRQ)
|
|
info.irq = -1;
|
|
|
|
if (of_find_i2c_driver(node, &info) < 0) {
|
|
irq_dispose_mapping(info.irq);
|
|
continue;
|
|
}
|
|
|
|
info.addr = *addr;
|
|
|
|
request_module(info.type);
|
|
|
|
result = i2c_new_device(adap, &info);
|
|
if (result == NULL) {
|
|
printk(KERN_ERR
|
|
"of-i2c: Failed to load driver for %s\n",
|
|
info.type);
|
|
irq_dispose_mapping(info.irq);
|
|
continue;
|
|
}
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(of_register_i2c_devices);
|
|
|
|
MODULE_LICENSE("GPL");
|