u-boot/drivers/w1-eeprom/eep_sandbox.c

62 lines
1.4 KiB
C
Raw Normal View History

/* 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,
};