From 5327b9b83a9c45a3fcbcda224a2b02d9eea9f6bb Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Sun, 6 Dec 2009 18:30:44 -0800 Subject: Doc: use misc-devices/ dir for drivers We have a directory for misc drivers documentation, let's use it. Signed-off-by: Jean Delvare Signed-off-by: Randy Dunlap Cc: "Darrick J. Wong" Cc: Rodolfo Giometti Signed-off-by: Linus Torvalds --- Documentation/misc-devices/c2port.txt | 90 +++++++++++++++++++++++++++++++++++ Documentation/misc-devices/ics932s401 | 31 ++++++++++++ 2 files changed, 121 insertions(+) create mode 100644 Documentation/misc-devices/c2port.txt create mode 100644 Documentation/misc-devices/ics932s401 (limited to 'Documentation/misc-devices') diff --git a/Documentation/misc-devices/c2port.txt b/Documentation/misc-devices/c2port.txt new file mode 100644 index 00000000000..d9bf93ea439 --- /dev/null +++ b/Documentation/misc-devices/c2port.txt @@ -0,0 +1,90 @@ + C2 port support + --------------- + +(C) Copyright 2007 Rodolfo Giometti + +This program is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + + + +Overview +-------- + +This driver implements the support for Linux of Silicon Labs (Silabs) +C2 Interface used for in-system programming of micro controllers. + +By using this driver you can reprogram the in-system flash without EC2 +or EC3 debug adapter. This solution is also useful in those systems +where the micro controller is connected via special GPIOs pins. + +References +---------- + +The C2 Interface main references are at (http://www.silabs.com) +Silicon Laboratories site], see: + +- AN127: FLASH Programming via the C2 Interface at +http://www.silabs.com/public/documents/tpub_doc/anote/Microcontrollers/Small_Form_Factor/en/an127.pdf, and + +- C2 Specification at +http://www.silabs.com/public/documents/tpub_doc/spec/Microcontrollers/en/C2spec.pdf, + +however it implements a two wire serial communication protocol (bit +banging) designed to enable in-system programming, debugging, and +boundary-scan testing on low pin-count Silicon Labs devices. Currently +this code supports only flash programming but extensions are easy to +add. + +Using the driver +---------------- + +Once the driver is loaded you can use sysfs support to get C2port's +info or read/write in-system flash. + +# ls /sys/class/c2port/c2port0/ +access flash_block_size flash_erase rev_id +dev_id flash_blocks_num flash_size subsystem/ +flash_access flash_data reset uevent + +Initially the C2port access is disabled since you hardware may have +such lines multiplexed with other devices so, to get access to the +C2port, you need the command: + +# echo 1 > /sys/class/c2port/c2port0/access + +after that you should read the device ID and revision ID of the +connected micro controller: + +# cat /sys/class/c2port/c2port0/dev_id +8 +# cat /sys/class/c2port/c2port0/rev_id +1 + +However, for security reasons, the in-system flash access in not +enabled yet, to do so you need the command: + +# echo 1 > /sys/class/c2port/c2port0/flash_access + +After that you can read the whole flash: + +# cat /sys/class/c2port/c2port0/flash_data > image + +erase it: + +# echo 1 > /sys/class/c2port/c2port0/flash_erase + +and write it: + +# cat image > /sys/class/c2port/c2port0/flash_data + +after writing you have to reset the device to execute the new code: + +# echo 1 > /sys/class/c2port/c2port0/reset diff --git a/Documentation/misc-devices/ics932s401 b/Documentation/misc-devices/ics932s401 new file mode 100644 index 00000000000..07a739f406d --- /dev/null +++ b/Documentation/misc-devices/ics932s401 @@ -0,0 +1,31 @@ +Kernel driver ics932s401 +====================== + +Supported chips: + * IDT ICS932S401 + Prefix: 'ics932s401' + Addresses scanned: I2C 0x69 + Datasheet: Publically available at the IDT website + +Author: Darrick J. Wong + +Description +----------- + +This driver implements support for the IDT ICS932S401 chip family. + +This chip has 4 clock outputs--a base clock for the CPU (which is likely +multiplied to get the real CPU clock), a system clock, a PCI clock, a USB +clock, and a reference clock. The driver reports selected and actual +frequency. If spread spectrum mode is enabled, the driver also reports by what +percent the clock signal is being spread, which should be between 0 and -0.5%. +All frequencies are reported in KHz. + +The ICS932S401 monitors all inputs continuously. The driver will not read +the registers more often than once every other second. + +Special Features +---------------- + +The clocks could be reprogrammed to increase system speed. I will not help you +do this, as you risk damaging your system! -- cgit v1.2.3