u-boot/drivers/w1-eeprom/ds24xxx.c
Maxime Ripard 0749f646c3 W1-EEPROM: add support for Maxim DS24 eeprom families
Add a driver that supports Maxim 1 wire EEPROMs families
DS24B33 and DS2431.
Can be extended for other families as well.

Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
[eugen.hristev@microchip.com: reworked driver]
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
2018-09-28 20:22:35 -04:00

55 lines
1.1 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
*
* Copyright (c) 2015 Free Electrons
* Copyright (c) 2015 NextThing Co
* Copyright (c) 2018 Microchip Technology, Inc.
*
*/
#include <common.h>
#include <linux/err.h>
#include <dm.h>
#include <w1-eeprom.h>
#include <w1.h>
#define W1_F2D_READ_EEPROM 0xf0
static int ds24xxx_read_buf(struct udevice *dev, unsigned int offset,
u8 *buf, unsigned int count)
{
w1_reset_select(dev);
w1_write_byte(dev, W1_F2D_READ_EEPROM);
w1_write_byte(dev, offset & 0xff);
w1_write_byte(dev, offset >> 8);
return w1_read_buf(dev, buf, count);
}
static int ds24xxx_probe(struct udevice *dev)
{
struct w1_device *w1;
w1 = dev_get_platdata(dev);
w1->id = 0;
return 0;
}
static const struct w1_eeprom_ops ds24xxx_ops = {
.read_buf = ds24xxx_read_buf,
};
static const struct udevice_id ds24xxx_id[] = {
{ .compatible = "maxim,ds24b33", .data = W1_FAMILY_DS24B33 },
{ .compatible = "maxim,ds2431", .data = W1_FAMILY_DS2431 },
{ },
};
U_BOOT_DRIVER(ds24xxx) = {
.name = "ds24xxx",
.id = UCLASS_W1_EEPROM,
.of_match = ds24xxx_id,
.ops = &ds24xxx_ops,
.probe = ds24xxx_probe,
};