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authorLinus Torvalds <torvalds@linux-foundation.org>2017-02-23 19:18:01 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2017-02-23 19:18:01 +0300
commitdf9cdc1727ed9debfce59c5f600d794a63fcbfeb (patch)
tree03438886f80e90213a6be5b21ac0d601584213a5 /Documentation/devicetree/bindings/mfd/aspeed-lpc.txt
parentbc49a7831b1137ce1c2dda1c57e3631655f5d2ae (diff)
parente93c10211d03c35271896b03a40d3eca4a674770 (diff)
downloadlinux-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 ...
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+======================================================================
+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>;
+};