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diff --git a/Documentation/driver-api/smsc_ece1099.rst b/Documentation/driver-api/smsc_ece1099.rst deleted file mode 100644 index 079277421eaf..000000000000 --- a/Documentation/driver-api/smsc_ece1099.rst +++ /dev/null @@ -1,60 +0,0 @@ -================================================= -Msc Keyboard Scan Expansion/GPIO Expansion device -================================================= - -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. |