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author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-02-23 19:18:01 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-02-23 19:18:01 +0300 |
commit | df9cdc1727ed9debfce59c5f600d794a63fcbfeb (patch) | |
tree | 03438886f80e90213a6be5b21ac0d601584213a5 /Documentation/devicetree/bindings/mfd/aspeed-lpc.txt | |
parent | bc49a7831b1137ce1c2dda1c57e3631655f5d2ae (diff) | |
parent | e93c10211d03c35271896b03a40d3eca4a674770 (diff) | |
download | linux-df9cdc1727ed9debfce59c5f600d794a63fcbfeb.tar.xz |
Merge tag 'mfd-for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd
Pull MFD updates from Lee Jones:
"Core Frameworks:
- Add new !TOUCHSCREEN_SUN4I dependency for SUN4I_GPADC
- List include/dt-bindings/mfd/* to files supported in MAINTAINERS
New Drivers:
- Intel Apollo Lake SPI NOR
- ST STM32 Timers (Advanced, Basic and PWM)
- Motorola 6556002 CPCAP (PMIC)
New Device Support:
- Add support for AXP221 to axp20x
- Add support for Intel Gemini Lake to intel-lpss-pci
- Add support for MT6323 LED to mt6397-core
- Add support for COMe-bBD#, COMe-bSL6, COMe-bKL6, COMe-cAL6 and
COMe-cKL6 to kempld-core
New Functionality:
- Add support for Analog CODAC to sun6i-prcm
- Add support for Watchdog to lpc_ich
Fix-ups:
- Error handling improvements; axp288_charger, axp20x, ab8500-sysctrl
- Adapt platform data handling; axp20x
- IRQ handling improvements; arizona, axp20x
- Remove superfluous code; arizona, axp20x, lpc_ich
- Trivial coding style/spelling fixes; axp20x, abx500, mfd.txt
- Regmap fix-ups; axp20x
- DT changes; mfd.txt, aspeed-lpc, aspeed-gfx, ab8500-core, tps65912,
mt6397
- Use new I2C probing mechanism; max77686
- Constification; rk808
Bug Fixes:
- Stop data transfer whilst suspended; cros_ec"
* tag 'mfd-for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: (43 commits)
mfd: lpc_ich: Enable watchdog on Intel Apollo Lake PCH
mfd: lpc_ich: Remove useless comments in core part
mfd: Add support for several boards to Kontron PLD driver
mfd: constify regmap_irq_chip structures
MAINTAINERS: Add include/dt-bindings/mfd to MFD entry
mfd: cpcap: Add minimal support
mfd: mt6397: Add MT6323 LED support into MT6397 driver
Documentation: devicetree: Add LED subnode binding for MT6323 PMIC
mfd: tps65912: Export OF device ID table as module aliases
mfd: ab8500-core: Rename clock device and compatible
mfd: cros_ec: Send correct suspend/resume event to EC
mfd: max77686: Remove I2C device ID table
mfd: max77686: Use the struct i2c_driver .probe_new instead of .probe
mfd: max77686: Use of_device_get_match_data() helper
mfd: max77686: Don't attempt to get i2c_device_id .data
mfd: ab8500-sysctrl: Handle probe deferral
mfd: intel-lpss: Add Intel Gemini Lake PCI IDs
mfd: axp20x: Fix AXP806 access errors on cold boot
mfd: cros_ec: Send suspend state notification to EC
mfd: cros_ec: Prevent data transfer while device is suspended
...
Diffstat (limited to 'Documentation/devicetree/bindings/mfd/aspeed-lpc.txt')
-rw-r--r-- | Documentation/devicetree/bindings/mfd/aspeed-lpc.txt | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/mfd/aspeed-lpc.txt b/Documentation/devicetree/bindings/mfd/aspeed-lpc.txt new file mode 100644 index 000000000000..514d82ced95b --- /dev/null +++ b/Documentation/devicetree/bindings/mfd/aspeed-lpc.txt @@ -0,0 +1,137 @@ +====================================================================== +Device tree bindings for the Aspeed Low Pin Count (LPC) Bus Controller +====================================================================== + +The LPC bus is a means to bridge a host CPU to a number of low-bandwidth +peripheral devices, replacing the use of the ISA bus in the age of PCI[0]. The +primary use case of the Aspeed LPC controller is as a slave on the bus +(typically in a Baseboard Management Controller SoC), but under certain +conditions it can also take the role of bus master. + +The LPC controller is represented as a multi-function device to account for the +mix of functionality it provides. The principle split is between the register +layout at the start of the I/O space which is, to quote the Aspeed datasheet, +"basically compatible with the [LPC registers from the] popular BMC controller +H8S/2168[1]", and everything else, where everything else is an eclectic +collection of functions with a esoteric register layout. "Everything else", +here labeled the "host" portion of the controller, includes, but is not limited +to: + +* An IPMI Block Transfer[2] Controller + +* An LPC Host Controller: Manages LPC functions such as host vs slave mode, the + physical properties of some LPC pins, configuration of serial IRQs, and + APB-to-LPC bridging amonst other functions. + +* An LPC Host Interface Controller: Manages functions exposed to the host such + as LPC firmware hub cycles, configuration of the LPC-to-AHB mapping, UART + management and bus snoop configuration. + +* A set of SuperIO[3] scratch registers: Enables implementation of e.g. custom + hardware management protocols for handover between the host and baseboard + management controller. + +Additionally the state of the LPC controller influences the pinmux +configuration, therefore the host portion of the controller is exposed as a +syscon as a means to arbitrate access. + +[0] http://www.intel.com/design/chipsets/industry/25128901.pdf +[1] https://www.renesas.com/en-sg/doc/products/mpumcu/001/rej09b0078_h8s2168.pdf?key=7c88837454702128622bee53acbda8f4 +[2] http://www.intel.com/content/dam/www/public/us/en/documents/product-briefs/ipmi-second-gen-interface-spec-v2-rev1-1.pdf +[3] https://en.wikipedia.org/wiki/Super_I/O + +Required properties +=================== + +- compatible: One of: + "aspeed,ast2400-lpc", "simple-mfd" + "aspeed,ast2500-lpc", "simple-mfd" + +- reg: contains the physical address and length values of the Aspeed + LPC memory region. + +- #address-cells: <1> +- #size-cells: <1> +- ranges: Maps 0 to the physical address and length of the LPC memory + region + +Required LPC Child nodes +======================== + +BMC Node +-------- + +- compatible: One of: + "aspeed,ast2400-lpc-bmc" + "aspeed,ast2500-lpc-bmc" + +- reg: contains the physical address and length values of the + H8S/2168-compatible LPC controller memory region + +Host Node +--------- + +- compatible: One of: + "aspeed,ast2400-lpc-host", "simple-mfd", "syscon" + "aspeed,ast2500-lpc-host", "simple-mfd", "syscon" + +- reg: contains the address and length values of the host-related + register space for the Aspeed LPC controller + +- #address-cells: <1> +- #size-cells: <1> +- ranges: Maps 0 to the address and length of the host-related LPC memory + region + +Example: + +lpc: lpc@1e789000 { + compatible = "aspeed,ast2500-lpc", "simple-mfd"; + reg = <0x1e789000 0x1000>; + + #address-cells = <1>; + #size-cells = <1>; + ranges = <0x0 0x1e789000 0x1000>; + + lpc_bmc: lpc-bmc@0 { + compatible = "aspeed,ast2500-lpc-bmc"; + reg = <0x0 0x80>; + }; + + lpc_host: lpc-host@80 { + compatible = "aspeed,ast2500-lpc-host", "simple-mfd", "syscon"; + reg = <0x80 0x1e0>; + reg-io-width = <4>; + + #address-cells = <1>; + #size-cells = <1>; + ranges = <0x0 0x80 0x1e0>; + }; +}; + +Host Node Children +================== + +LPC Host Controller +------------------- + +The Aspeed LPC Host Controller configures the Low Pin Count (LPC) bus behaviour +between the host and the baseboard management controller. The registers exist +in the "host" portion of the Aspeed LPC controller, which must be the parent of +the LPC host controller node. + +Required properties: + +- compatible: One of: + "aspeed,ast2400-lhc"; + "aspeed,ast2500-lhc"; + +- reg: contains offset/length values of the LHC memory regions. In the + AST2400 and AST2500 there are two regions. + +Example: + +lhc: lhc@20 { + compatible = "aspeed,ast2500-lhc"; + reg = <0x20 0x24 0x48 0x8>; +}; |