c58da9fbc3
IMPORTANT: this change has a docs/UPDATING entry! This rename is unfortunately necessary because NetBSD has decided to create its own service(8) utility, and we will want to import theirs as well. The two can obviously not coexist. Also move ours from /bin to /sbin, as it is a superuser-only utility. Change-Id: Ic6e46ffb3a84b4747d2fdcb0d74e62dbea065039
37 lines
1.1 KiB
Plaintext
37 lines
1.1 KiB
Plaintext
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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/sbin/minix-service up /service/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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/sbin/minix-service down tps65950.1.48
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