diff options
Diffstat (limited to 'Documentation/i2c/chips/pcf8574')
-rw-r--r-- | Documentation/i2c/chips/pcf8574 | 12 |
1 files changed, 5 insertions, 7 deletions
diff --git a/Documentation/i2c/chips/pcf8574 b/Documentation/i2c/chips/pcf8574 index 5c1ad1376b62..235815c075ff 100644 --- a/Documentation/i2c/chips/pcf8574 +++ b/Documentation/i2c/chips/pcf8574 | |||
@@ -4,13 +4,13 @@ Kernel driver pcf8574 | |||
4 | Supported chips: | 4 | Supported chips: |
5 | * Philips PCF8574 | 5 | * Philips PCF8574 |
6 | Prefix: 'pcf8574' | 6 | Prefix: 'pcf8574' |
7 | Addresses scanned: I2C 0x20 - 0x27 | 7 | Addresses scanned: none |
8 | Datasheet: Publicly available at the Philips Semiconductors website | 8 | Datasheet: Publicly available at the Philips Semiconductors website |
9 | http://www.semiconductors.philips.com/pip/PCF8574P.html | 9 | http://www.semiconductors.philips.com/pip/PCF8574P.html |
10 | 10 | ||
11 | * Philips PCF8574A | 11 | * Philips PCF8574A |
12 | Prefix: 'pcf8574a' | 12 | Prefix: 'pcf8574a' |
13 | Addresses scanned: I2C 0x38 - 0x3f | 13 | Addresses scanned: none |
14 | Datasheet: Publicly available at the Philips Semiconductors website | 14 | Datasheet: Publicly available at the Philips Semiconductors website |
15 | http://www.semiconductors.philips.com/pip/PCF8574P.html | 15 | http://www.semiconductors.philips.com/pip/PCF8574P.html |
16 | 16 | ||
@@ -38,12 +38,10 @@ For more informations see the datasheet. | |||
38 | Accessing PCF8574(A) via /sys interface | 38 | Accessing PCF8574(A) via /sys interface |
39 | ------------------------------------- | 39 | ------------------------------------- |
40 | 40 | ||
41 | ! Be careful ! | ||
42 | The PCF8574(A) is plainly impossible to detect ! Stupid chip. | 41 | The PCF8574(A) is plainly impossible to detect ! Stupid chip. |
43 | So every chip with address in the interval [20..27] and [38..3f] are | 42 | So, you have to pass the I2C bus and address of the installed PCF857A |
44 | detected as PCF8574(A). If you have other chips in this address | 43 | and PCF8574A devices explicitly to the driver at load time via the |
45 | range, the workaround is to load this module after the one | 44 | force=... parameter. |
46 | for your others chips. | ||
47 | 45 | ||
48 | On detection (i.e. insmod, modprobe et al.), directories are being | 46 | On detection (i.e. insmod, modprobe et al.), directories are being |
49 | created for each detected PCF8574(A): | 47 | created for each detected PCF8574(A): |