Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit c43c1be0 authored by Ingo Molnar's avatar Ingo Molnar
Browse files

Merge branch 'linus' into x86/urgent

parents e22146e6 a3cf8593

Documentation/i2c/chips/max6875

+1 −1
Original line number Diff line number Diff line
@@ -49,7 +49,7 @@ $ modprobe max6875 force=0,0x50 


The MAX6874/MAX6875 ignores address bit 0, so this driver attaches to multiple

addresses.  For example, for address 0x50, it also reserves 0x51.

The even-address instance is called 'max6875', the odd one is 'max6875 subclient'.

The even-address instance is called 'max6875', the odd one is 'dummy'.





Programming the chip using i2c-dev

Documentation/i2c/chips/pca9539

+9 −1
Original line number Diff line number Diff line
@@ -7,7 +7,7 @@ drivers/gpio/pca9539.c instead. 
Supported chips:

  * Philips PCA9539

    Prefix: 'pca9539'

    Addresses scanned: 0x74 - 0x77

    Addresses scanned: none

    Datasheet:

        http://www.semiconductors.philips.com/acrobat/datasheets/PCA9539_2.pdf
@@ -23,6 +23,14 @@ The input sense can also be inverted. 
The 16 lines are split between two bytes.





Detection

---------



The PCA9539 is difficult to detect and not commonly found in PC machines,

so you have to pass the I2C bus and address of the installed PCA9539

devices explicitly to the driver at load time via the force=... parameter.





Sysfs entries

-------------

Documentation/i2c/chips/pcf8574

+5 −7
Original line number Diff line number Diff line
@@ -4,13 +4,13 @@ Kernel driver pcf8574 
Supported chips:

  * Philips PCF8574

    Prefix: 'pcf8574'

    Addresses scanned: I2C 0x20 - 0x27

    Addresses scanned: none

    Datasheet: Publicly available at the Philips Semiconductors website

               http://www.semiconductors.philips.com/pip/PCF8574P.html



 * Philips PCF8574A

    Prefix: 'pcf8574a'

    Addresses scanned: I2C 0x38 - 0x3f

    Addresses scanned: none

    Datasheet: Publicly available at the Philips Semiconductors website

               http://www.semiconductors.philips.com/pip/PCF8574P.html
@@ -38,12 +38,10 @@ For more informations see the datasheet. 
Accessing PCF8574(A) via /sys interface

-------------------------------------



! Be careful !

The PCF8574(A) is plainly impossible to detect ! Stupid chip.

So every chip with address in the interval [20..27] and [38..3f] are

detected as PCF8574(A). If you have other chips in this address

range, the workaround is to load this module after the one

for your others chips.

So, you have to pass the I2C bus and address of the installed PCF857A

and PCF8574A devices explicitly to the driver at load time via the

force=... parameter.



On detection (i.e. insmod, modprobe et al.), directories are being

created for each detected PCF8574(A):

Documentation/i2c/chips/pcf8575

+3 −6
Original line number Diff line number Diff line
@@ -40,12 +40,9 @@ Detection 
---------



There is no method known to detect whether a chip on a given I2C address is

a PCF8575 or whether it is any other I2C device. So there are two alternatives

to let the driver find the installed PCF8575 devices:

- Load this driver after any other I2C driver for I2C devices with addresses

  in the range 0x20 .. 0x27.

- Pass the I2C bus and address of the installed PCF8575 devices explicitly to

  the driver at load time via the probe=... or force=... parameters.

a PCF8575 or whether it is any other I2C device, so you have to pass the I2C

bus and address of the installed PCF8575 devices explicitly to the driver at

load time via the force=... parameter.



/sys interface

--------------

Makefile

+2 −2
Original line number Diff line number Diff line
@@ -508,6 +508,8 @@ else 
KBUILD_CFLAGS	+= -O2

endif



include $(srctree)/arch/$(SRCARCH)/Makefile



ifneq (CONFIG_FRAME_WARN,0)

KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})

endif
@@ -516,8 +518,6 @@ endif 
# Arch Makefiles may override this setting

KBUILD_CFLAGS += $(call cc-option, -fno-stack-protector)



include $(srctree)/arch/$(SRCARCH)/Makefile



ifdef CONFIG_FRAME_POINTER

KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls

else