mirror of
https://github.com/brain-hackers/u-boot-brain
synced 2024-08-30 22:08:52 +09:00
![Eugen Hristev](/assets/img/avatar_default.png)
Add a sandbox driver for a one wire EEPROM memory Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
62 lines
1.4 KiB
C
62 lines
1.4 KiB
C
/* SPDX-License-Identifier: GPL-2.0+
|
|
*
|
|
* 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
|
|
|
|
#define EEP_SANDBOX_SAMPLE_MEM "this is a sample EEPROM memory string."
|
|
|
|
static int eep_sandbox_read_buf(struct udevice *dev, unsigned int offset,
|
|
u8 *buf, unsigned int count)
|
|
{
|
|
/* do not allow to copy more than our maximum sample string */
|
|
if (offset + count < strlen(EEP_SANDBOX_SAMPLE_MEM)) {
|
|
offset = 0;
|
|
count = strlen(EEP_SANDBOX_SAMPLE_MEM);
|
|
}
|
|
strncpy((char *)buf, EEP_SANDBOX_SAMPLE_MEM, count);
|
|
|
|
/*
|
|
* in case the w1 subsystem uses some different kind of sandbox testing,
|
|
* like randomized gpio values , we take the buffer from there
|
|
*/
|
|
|
|
w1_reset_select(dev);
|
|
|
|
w1_write_byte(dev, W1_F2D_READ_EEPROM);
|
|
w1_write_byte(dev, offset & 0xff);
|
|
w1_write_byte(dev, offset >> 8);
|
|
|
|
w1_read_buf(dev, buf, count);
|
|
|
|
/*
|
|
* even if read buf from w1 fails, return success as we hardcoded
|
|
* the buffer.
|
|
*/
|
|
return 0;
|
|
}
|
|
|
|
static const struct w1_eeprom_ops eep_sandbox_ops = {
|
|
.read_buf = eep_sandbox_read_buf,
|
|
};
|
|
|
|
static const struct udevice_id eep_sandbox_id[] = {
|
|
{ .compatible = "sandbox,w1-eeprom", .data = W1_FAMILY_EEP_SANDBOX },
|
|
{ },
|
|
};
|
|
|
|
U_BOOT_DRIVER(eep_sandbox) = {
|
|
.name = "eep_sandbox",
|
|
.id = UCLASS_W1_EEPROM,
|
|
.of_match = eep_sandbox_id,
|
|
.ops = &eep_sandbox_ops,
|
|
};
|