37 lines
1.1 KiB
Text
37 lines
1.1 KiB
Text
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TPS65950 Driver (Power Management IC)
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=====================================
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Overview
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--------
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This driver is for the power management chip commonly found on the
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BeagleBoard-xM.
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Limitations
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-----------
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The TPS65950 has a pin labelled MSECURE which provides a form of write
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protection. Depending on the pin's state (high or low), writing to certain
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registers is disabled or enabled. The pin is driven by a GPIO on the SoC.
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There isn't a good way to access that pin on the SoC yet, so the PMIC
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is always in the default insecure mode. It isn't really insecure as this
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driver is the only one that the i2c bus driver will allow to access the
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PMIC.
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This is a huge chip. It has two I2C controllers, one with 4 slave addresses
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hosting 256 registers per address. The TRM is over 900 pages. Given the
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limited usefulness of some peripherals on the chip, not everything is
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implemented.
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Testing the Code
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----------------
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Starting up an instance:
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/bin/service up /usr/sbin/tps65950 -label tps65950.1.48 \
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-args 'bus=1 address=0x48'
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Killing an instance:
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/bin/service down tps65950.1.48
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