diff options
author | Jean Delvare <jdelvare@suse.de> | 2019-07-04 05:34:02 -0400 |
---|---|---|
committer | Wolfram Sang <wsa@the-dreams.de> | 2019-07-05 14:59:10 -0400 |
commit | ed6182a83924c2385679afd5a3b9cd3d41e2ef44 (patch) | |
tree | 82d651d87bf82737a30eee47db3cf4b4b9ab904a /Documentation/i2c | |
parent | 051d769f0a36b4642897d909cef980f944ae20ab (diff) |
i2c: i801: Documentation update
The i2c-i801 driver documentation needs some dusting:
* Mention disable_features flag 0x20.
* The i2c_ec driver has been removed from the kernel long ago. Driver
i2c-scmi serves the same purpose for more recent hardware.
* Replace obsolete /proc paths with equivalent /sys paths.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'Documentation/i2c')
-rw-r--r-- | Documentation/i2c/busses/i2c-i801 | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/Documentation/i2c/busses/i2c-i801 b/Documentation/i2c/busses/i2c-i801 index 04b5de80ce4e..f426c13c63a9 100644 --- a/Documentation/i2c/busses/i2c-i801 +++ b/Documentation/i2c/busses/i2c-i801 | |||
@@ -60,6 +60,7 @@ question doesn't work as intended for whatever reason. Bit values: | |||
60 | 0x02 disable the block buffer | 60 | 0x02 disable the block buffer |
61 | 0x08 disable the I2C block read functionality | 61 | 0x08 disable the I2C block read functionality |
62 | 0x10 don't use interrupts | 62 | 0x10 don't use interrupts |
63 | 0x20 disable SMBus Host Notify | ||
63 | 64 | ||
64 | 65 | ||
65 | Description | 66 | Description |
@@ -120,16 +121,15 @@ BIOS to enable it, it means it has been hidden by the BIOS code. Asus is | |||
120 | well known for first doing this on their P4B motherboard, and many other | 121 | well known for first doing this on their P4B motherboard, and many other |
121 | boards after that. Some vendor machines are affected as well. | 122 | boards after that. Some vendor machines are affected as well. |
122 | 123 | ||
123 | The first thing to try is the "i2c_ec" ACPI driver. It could be that the | 124 | The first thing to try is the "i2c-scmi" ACPI driver. It could be that the |
124 | SMBus was hidden on purpose because it'll be driven by ACPI. If the | 125 | SMBus was hidden on purpose because it'll be driven by ACPI. If the |
125 | i2c_ec driver works for you, just forget about the i2c-i801 driver and | 126 | i2c-scmi driver works for you, just forget about the i2c-i801 driver and |
126 | don't try to unhide the ICH SMBus. Even if i2c_ec doesn't work, you | 127 | don't try to unhide the ICH SMBus. Even if i2c-scmi doesn't work, you |
127 | better make sure that the SMBus isn't used by the ACPI code. Try loading | 128 | better make sure that the SMBus isn't used by the ACPI code. Try loading |
128 | the "fan" and "thermal" drivers, and check in /proc/acpi/fan and | 129 | the "fan" and "thermal" drivers, and check in /sys/class/thermal. If you |
129 | /proc/acpi/thermal_zone. If you find anything there, it's likely that | 130 | find a thermal zone with type "acpitz", it's likely that the ACPI is |
130 | the ACPI is accessing the SMBus and it's safer not to unhide it. Only | 131 | accessing the SMBus and it's safer not to unhide it. Only once you are |
131 | once you are certain that ACPI isn't using the SMBus, you can attempt | 132 | certain that ACPI isn't using the SMBus, you can attempt to unhide it. |
132 | to unhide it. | ||
133 | 133 | ||
134 | In order to unhide the SMBus, we need to change the value of a PCI | 134 | In order to unhide the SMBus, we need to change the value of a PCI |
135 | register before the kernel enumerates the PCI devices. This is done in | 135 | register before the kernel enumerates the PCI devices. This is done in |