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93c4bb3666
The ds28ec20 eeprom is (almost) backward compatible with the
ds2433. The only differences are:
- the eeprom size is now 2560 bytes instead of 512;
- the number of pages is now 80 (same page size as the ds2433: 256 bits);
- the programming time has increased from 5ms to 10ms;
This patch adds support for the ds28ec20 to the ds2433 driver. From
the datasheet: The DS28EC20 provides a high degree of backward
compatibility with the DS2433. Besides the different family codes, the
only protocol change that is required on an existing DS2433
implementation is a lengthening of the programming duration (tPROG)
from 5ms to 10ms.
dmesg now returns:
w1_master_driver w1_bus_master1: Attaching one wire slave 43.000000478756 crc e0
instead of:
w1_master_driver w1_bus_master1: Attaching one wire slave 43.000000478756 crc e0
w1_master_driver w1_bus_master1: Family 43 for 43.000000478756.e0 is not registered.
Test script writing/reading random data (CONFIG_W1_SLAVE_DS2433_CRC is
not set):
#!/bin/sh
EEPROM=/sys/bus/w1/devices/43-000000478756/eeprom
BINFILE1=/home/root/file1.bin
BINFILE2=/home/root/file2.bin
for BS in 1 2 3 4 8 16 32 64 128 256 512 1024 2560; do
dd if=/dev/random of=${BINFILE1} bs=${BS} count=1 status=none
dd if=${BINFILE1} of=${EEPROM} status=none
dd if=${EEPROM} of=${BINFILE2} bs=${BS} count=1 status=none
if ! cmp --silent ${BINFILE1} ${BINFILE2}; then
echo file1
hexdump ${BINFILE1}
echo file2
hexdump ${BINFILE2}
echo FAIL
exit 1
fi
echo "${BS} OK!"
done
Results:
# ./test.sh
1 OK!
2 OK!
3 OK!
4 OK!
8 OK!
16 OK!
32 OK!
64 OK!
128 OK!
256 OK!
512 OK!
1024 OK!
2560 OK!
Tests with CONFIG_W1_SLAVE_DS2433_CRC=y:
$ cat /proc/config.gz | gunzip | grep CONFIG_W1_SLAVE_DS2433
CONFIG_W1_SLAVE_DS2433=m
CONFIG_W1_SLAVE_DS2433_CRC=y
# create a 32 bytes block with a crc, i.e.:
00000000 31 32 33 34 35 36 37 38 39 3a 3b 3c 3d 3e 3f 40 |123456789:;<=>?@|
00000010 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e ba 63 |ABCDEFGHIJKLMN.c|
# fill all 80 blocks
$ dd if=test.bin of=/sys/bus/w1/devices/43-000000478756/eeprom bs=32 count=80
# read back all blocks, i.e.:
$ hexdump -C /sys/bus/w1/devices/43-000000478756/eeprom
00000000 31 32 33 34 35 36 37 38 39 3a 3b 3c 3d 3e 3f 40 |123456789:;<=>?@|
00000010 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e ba 63 |ABCDEFGHIJKLMN.c|
00000020 31 32 33 34 35 36 37 38 39 3a 3b 3c 3d 3e 3f 40 |123456789:;<=>?@|
00000030 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e ba 63 |ABCDEFGHIJKLMN.c|
...
000009e0 31 32 33 34 35 36 37 38 39 3a 3b 3c 3d 3e 3f 40 |123456789:;<=>?@|
000009f0 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e ba 63 |ABCDEFGHIJKLMN.c|
00000a00
Note: both memories (ds2433 and ds28ec20) have been tested with the
new driver.
Signed-off-by: Marc Ferland <marc.ferland@sonatest.com>
Co-developed-by: Jean-Francois Dagenais <jeff.dagenais@gmail.com>
Signed-off-by: Jean-Francois Dagenais <jeff.dagenais@gmail.com>
Link: https://lore.kernel.org/r/20231218150230.1992448-6-marc.ferland@sonatest.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.