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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-05 12:01:30 +0900
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-05 12:01:30 +0900
commit578f1ef91aa92beb571bfb9af8f4d18f405f3b9e (patch)
tree8ff59e772d09180b7e7f952a8c90a1bcf25e1d19 /Documentation/smsc_ece1099.txt
parentecefbd94b834fa32559d854646d777c56749ef1c (diff)
parent74d8378159de16a0a1d1975d4778120d263d6000 (diff)
Merge tag 'mfd-3.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6
Pull MFD changes from Samuel Ortiz: "MFD bits for the 3.7 merge window. As usual we have a few new drivers: - TI LP8788 - TI OMAP USB TLL - Maxim MAX8907 - SMSC ECE1099 - Dialog Semiconductor DA9055 - A simpler syscon driver that allow us to get rid of the anatop one. Drivers are also gradually getting Device Tree and IRQ domain support. The following drivers got DT support: - palmas, 88pm860x, tc3589x and twl4030-audio And those ones now use the IRQ domain APIs: - 88pm860x, tc3589x, db8500_prcmu Also some other interesting changes: - Intel's ICH LPC now supports Lynx Point - TI's twl4030-audio added a GPO child - tps6527 enabled its backlight subdevice - The twl6030 pwm driver moved to the new PWM subsystem And finally a bunch of cleanup and casual fixes for mc13xxx, 88pm860x, palmas, ab8500, wm8994, wm5110, max8907 and the tps65xxx family." Fix up various annoying conflicts: the DT and IRQ domain support came in twice and was already in 3.6. And then it was apparently rebased. Guys, DON'T REBASE! * tag 'mfd-3.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6: (89 commits) ARM: dts: Enable 88pm860x pmic mfd: 88pm860x: Move gpadc init into touch mfd: 88pm860x: Device tree support mfd: 88pm860x: Use irqdomain mfd: smsc: Add support for smsc gpio io/keypad driver backlight: tps65217_bl: Add missing platform_set_drvdata in tps65217_bl_probe mfd: DA9055 core driver mfd: tps65910: Add alarm interrupt of TPS65910 RTC to mfd device list mfd: wm5110: Add register patches for revision B mfd: wm5110: Disable control interface error report for WM5110 rev B mfd: max8907: Remove regulator-compatible from DT docs backlight: Add TPS65217 WLED driver mfd: Add backlight as subdevice to the tps65217 mfd: Provide the PRCMU with its own IRQ domain mfd: Fix max8907 sparse warning mfd: Add lp8788 mfd driver mfd: dbx500: Provide a more accurate smp_twd clock mfd: rc5t583: Fix warning messages regulator: palmas: Add DT support mfd: palmas: Change regulator defns to better suite DT ...
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+What is smsc-ece1099?
+----------------------
+
+The ECE1099 is a 40-Pin 3.3V Keyboard Scan Expansion
+or GPIO Expansion device. The device supports a keyboard
+scan matrix of 23x8. The device is connected to a Master
+via the SMSC BC-Link interface or via the SMBus.
+Keypad scan Input(KSI) and Keypad Scan Output(KSO) signals
+are multiplexed with GPIOs.
+
+Interrupt generation
+--------------------
+
+Interrupts can be generated by an edge detection on a GPIO
+pin or an edge detection on one of the bus interface pins.
+Interrupts can also be detected on the keyboard scan interface.
+The bus interrupt pin (BC_INT# or SMBUS_INT#) is asserted if
+any bit in one of the Interrupt Status registers is 1 and
+the corresponding Interrupt Mask bit is also 1.
+
+In order for software to determine which device is the source
+of an interrupt, it should first read the Group Interrupt Status Register
+to determine which Status register group is a source for the interrupt.
+Software should read both the Status register and the associated Mask register,
+then AND the two values together. Bits that are 1 in the result of the AND
+are active interrupts. Software clears an interrupt by writing a 1 to the
+corresponding bit in the Status register.
+
+Communication Protocol
+----------------------
+
+- SMbus slave Interface
+ The host processor communicates with the ECE1099 device
+ through a series of read/write registers via the SMBus
+ interface. SMBus is a serial communication protocol between
+ a computer host and its peripheral devices. The SMBus data
+ rate is 10KHz minimum to 400 KHz maximum
+
+- Slave Bus Interface
+ The ECE1099 device SMBus implementation is a subset of the
+ SMBus interface to the host. The device is a slave-only SMBus device.
+ The implementation in the device is a subset of SMBus since it
+ only supports four protocols.
+
+ The Write Byte, Read Byte, Send Byte, and Receive Byte protocols are the
+ only valid SMBus protocols for the device.
+
+- BC-LinkTM Interface
+ The BC-Link is a proprietary bus that allows communication
+ between a Master device and a Companion device. The Master
+ device uses this serial bus to read and write registers
+ located on the Companion device. The bus comprises three signals,
+ BC_CLK, BC_DAT and BC_INT#. The Master device always provides the
+ clock, BC_CLK, and the Companion device is the source for an
+ independent asynchronous interrupt signal, BC_INT#. The ECE1099
+ supports BC-Link speeds up to 24MHz.