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authorTakashi Iwai <tiwai@suse.de>2020-08-03 14:41:43 +0200
committerTakashi Iwai <tiwai@suse.de>2020-08-03 14:41:43 +0200
commit103f528d3bc35d2b6e726a3fffd879e492d191c2 (patch)
tree2829604c2386f96e228fac7841e49906f698dfff /Documentation/i2c
parent07c9983b567d0ef33aefc063299de95a987e12a8 (diff)
parent84569f329f7fcb40b7b1860f273b2909dabf2a2b (diff)
Merge tag 'asoc-v5.9' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Updates for v5.9 The biggest changes here one again come from Mormioto-san who has continued his dilligent work cleaning up long standing issues in the APIs, it's particularly nice to see the transition from digital_mute() to mute_stream() finally completed. There's also been a lot of work on the x86 code again, this time a big focus has been on cleaning up some issues identified by various static tests, and on the Freescale systems. Otherwise the biggest thing has been a lot of driver additions: - Convert users of digital_mute() to mute_stream(). - Simplify I/O helper functions. - Add a helper for getting the RTD from a substream. - Many, many fixes and cleanups to the x86 code. - New drivers for Freescale MQS and i.MX6sx, Intel KeemBay I2S, Maxim MAX98360A and MAX98373 Soundwire, several Mediatek boards, nVidia Tegra 186 and 210, RealTek RL6231, Samsung Midas and Aries boards (some of the first phones I worked on!) and TI J721e EVM.
Diffstat (limited to 'Documentation/i2c')
-rw-r--r--Documentation/i2c/slave-eeprom-backend.rst22
-rw-r--r--Documentation/i2c/smbus-protocol.rst2
2 files changed, 18 insertions, 6 deletions
diff --git a/Documentation/i2c/slave-eeprom-backend.rst b/Documentation/i2c/slave-eeprom-backend.rst
index 0b8cd83698e0..38d951f10302 100644
--- a/Documentation/i2c/slave-eeprom-backend.rst
+++ b/Documentation/i2c/slave-eeprom-backend.rst
@@ -1,14 +1,26 @@
==============================
-Linux I2C slave eeprom backend
+Linux I2C slave EEPROM backend
==============================
-by Wolfram Sang <wsa@sang-engineering.com> in 2014-15
+by Wolfram Sang <wsa@sang-engineering.com> in 2014-20
-This is a proof-of-concept backend which acts like an EEPROM on the connected
-I2C bus. The memory contents can be modified from userspace via this file
-located in sysfs::
+This backend simulates an EEPROM on the connected I2C bus. Its memory contents
+can be accessed from userspace via this file located in sysfs::
/sys/bus/i2c/devices/<device-directory>/slave-eeprom
+The following types are available: 24c02, 24c32, 24c64, and 24c512. Read-only
+variants are also supported. The name needed for instantiating has the form
+'slave-<type>[ro]'. Examples follow:
+
+24c02, read/write, address 0x64:
+ # echo slave-24c02 0x1064 > /sys/bus/i2c/devices/i2c-1/new_device
+
+24c512, read-only, address 0x42:
+ # echo slave-24c512ro 0x1042 > /sys/bus/i2c/devices/i2c-1/new_device
+
+You can also preload data during boot if a device-property named
+'firmware-name' contains a valid filename (DT or ACPI only).
+
As of 2015, Linux doesn't support poll on binary sysfs files, so there is no
notification when another master changed the content.
diff --git a/Documentation/i2c/smbus-protocol.rst b/Documentation/i2c/smbus-protocol.rst
index c2e29633071e..64689d19dd51 100644
--- a/Documentation/i2c/smbus-protocol.rst
+++ b/Documentation/i2c/smbus-protocol.rst
@@ -57,7 +57,7 @@ SMBus Quick Command
This sends a single bit to the device, at the place of the Rd/Wr bit::
- A Addr Rd/Wr [A] P
+ S Addr Rd/Wr [A] P
Functionality flag: I2C_FUNC_SMBUS_QUICK