Documentation/i2c/gpio-fault-injection.rst

12 'i2c-fault-injector' subdirectory in the Kernel debugfs filesystem, usually
15 injection. They will be described now along with their intended use-cases.
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52 in a bus master driver, make sure you checked your hardware setup for such
53 devices before. And always verify with a scope or logic analyzer!
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60 it will stop at the ACK phase after the address of the client has been
61 transmitted. Because the device will ACK its presence, this results in SDA
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73 The injector will again stop at one ACK phase, so the device will keep SDA low
78 b) after the address byte, a 0x00 byte will be transferred. Then, stop at ACK.
90 bus arbitration against another master in a multi-master setup.
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97 and wait for the next bus clock. The process is interruptible, though.
99 Arbitration lost is achieved by waiting for SCL going down by the master under
100 test and then pulling SDA low for some time. So, the I2C address sent out
106 corrupted. A good starting point for using this fault injector on an otherwise
110   # i2cget -y <bus_to_test> 0x3f
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126 The calling process will then sleep and wait for the next bus clock. The
129 Start of a transfer is detected by waiting for SCL going down by the master
130 under test.  A good starting point for using this fault injector is::
133   # i2cget -y <bus_to_test> <some_address>