84e55bdd8b
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+
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*
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* Copyright (c) 2018 Microchip Technology, Inc.
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*
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*/
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#include <common.h>
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#include <linux/err.h>
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#include <dm.h>
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#include <w1-eeprom.h>
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#include <w1.h>
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#define W1_F2D_READ_EEPROM 0xf0
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#define EEP_SANDBOX_SAMPLE_MEM "this is a sample EEPROM memory string."
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static int eep_sandbox_read_buf(struct udevice *dev, unsigned int offset,
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u8 *buf, unsigned int count)
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{
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/* do not allow to copy more than our maximum sample string */
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if (offset + count < strlen(EEP_SANDBOX_SAMPLE_MEM)) {
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offset = 0;
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count = strlen(EEP_SANDBOX_SAMPLE_MEM);
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}
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strncpy((char *)buf, EEP_SANDBOX_SAMPLE_MEM, count);
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/*
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* in case the w1 subsystem uses some different kind of sandbox testing,
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* like randomized gpio values , we take the buffer from there
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*/
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w1_reset_select(dev);
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w1_write_byte(dev, W1_F2D_READ_EEPROM);
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w1_write_byte(dev, offset & 0xff);
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w1_write_byte(dev, offset >> 8);
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w1_read_buf(dev, buf, count);
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/*
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* even if read buf from w1 fails, return success as we hardcoded
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* the buffer.
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*/
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return 0;
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}
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static const struct w1_eeprom_ops eep_sandbox_ops = {
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.read_buf = eep_sandbox_read_buf,
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};
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static const struct udevice_id eep_sandbox_id[] = {
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{ .compatible = "sandbox,w1-eeprom", .data = W1_FAMILY_EEP_SANDBOX },
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{ },
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};
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U_BOOT_DRIVER(eep_sandbox) = {
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.name = "eep_sandbox",
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.id = UCLASS_W1_EEPROM,
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.of_match = eep_sandbox_id,
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.ops = &eep_sandbox_ops,
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};
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