diff options
author | Markus Franke <franm@hrz.tu-chemnitz.de> | 2012-05-25 18:45:12 -0400 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-06-13 19:47:10 -0400 |
commit | fbf7f7b4e2ae40f790828c86d31beff2d49e9ac8 (patch) | |
tree | 101a1272b8f1ebdf948945ade2aa7cff1b9a7311 /Documentation/w1 | |
parent | a59d6293e5372d7c35212932e083e2a541151eff (diff) |
w1: Add 1-wire slave device driver for DS28E04-100
Signed-off-by: Markus Franke <franm@hrz.tu-chemnitz.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation/w1')
-rw-r--r-- | Documentation/w1/slaves/w1_ds28e04 | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/Documentation/w1/slaves/w1_ds28e04 b/Documentation/w1/slaves/w1_ds28e04 new file mode 100644 index 000000000000..85bc9a7e02fe --- /dev/null +++ b/Documentation/w1/slaves/w1_ds28e04 | |||
@@ -0,0 +1,36 @@ | |||
1 | Kernel driver w1_ds28e04 | ||
2 | ======================== | ||
3 | |||
4 | Supported chips: | ||
5 | * Maxim DS28E04-100 4096-Bit Addressable 1-Wire EEPROM with PIO | ||
6 | |||
7 | supported family codes: | ||
8 | W1_FAMILY_DS28E04 0x1C | ||
9 | |||
10 | Author: Markus Franke, <franke.m@sebakmt.com> <franm@hrz.tu-chemnitz.de> | ||
11 | |||
12 | Description | ||
13 | ----------- | ||
14 | |||
15 | Support is provided through the sysfs files "eeprom" and "pio". CRC checking | ||
16 | during memory accesses can optionally be enabled/disabled via the device | ||
17 | attribute "crccheck". The strong pull-up can optionally be enabled/disabled | ||
18 | via the module parameter "w1_strong_pullup". | ||
19 | |||
20 | Memory Access | ||
21 | |||
22 | A read operation on the "eeprom" file reads the given amount of bytes | ||
23 | from the EEPROM of the DS28E04. | ||
24 | |||
25 | A write operation on the "eeprom" file writes the given byte sequence | ||
26 | to the EEPROM of the DS28E04. If CRC checking mode is enabled only | ||
27 | fully alligned blocks of 32 bytes with valid CRC16 values (in bytes 30 | ||
28 | and 31) are allowed to be written. | ||
29 | |||
30 | PIO Access | ||
31 | |||
32 | The 2 PIOs of the DS28E04-100 are accessible via the "pio" sysfs file. | ||
33 | |||
34 | The current status of the PIO's is returned as an 8 bit value. Bit 0/1 | ||
35 | represent the state of PIO_0/PIO_1. Bits 2..7 do not care. The PIO's are | ||
36 | driven low-active, i.e. the driver delivers/expects low-active values. | ||