Wiki

This version is outdated by a newer approved version.DiffThis version (05 Sep 2012 14:08) was approved by Michael Hennerich.The Previously approved version (14 Dec 2011 11:02) is available.Diff

This is an old revision of the document!


ADP5589 Input Keyboard and GPIO Linux Driver

Supported Devices

Evaluation Boards

Description

ADP5589

ADP5585

Description

The driver supports multiple key press detection and resolution.
It independently delivers key press and key release events in
chronological order to the Linux input device system.

This allows SHIFT + ANYKEY, ALT + F1 or CTRL + ALT + DEL sequences.

Since the ADP5589 buffers events in its internal FIFO,
it’s unlikely that events are lost due to heavy system
load and interrupt latencies.

Configuration

Software configurable features

  • Configurable keypad size matrix up to 11 × 8 (columns, rows).
  • Support for switch events.
  • Enabling and disabling automatic key repeat feature.
  • Lock/Unlock key feature with configurable timer. (ADP5589 only)
  • Two independent and flexible reset signal generators with either two or three software configurable keys.
  • Flexible debounce, 100 kOhm/300kOhm pull-up and 300 kOhm pull-down configuration on all configurable I/Os.
  • Configurable keypad scan cycle times.
  • Unused row and column pins are exported as general-purpose inputs/outputs to GPIOLIB

Source Code

Status

Source Mainlined?
git Yes

Files

Example platform device initialization

For compile time configuration, it’s common Linux practice to keep board- and application-specific configuration out of the main driver file, instead putting it into the board support file.

For devices on custom boards, as typical of embedded and SoC-(system-on-chip) based hardware, Linux uses platform_data to point to board-specific structures describing devices and how they are connected to the SoC. This can include available ports, chip variants, preferred modes, default initialization, additional pin roles, and so on. This shrinks the board-support packages (BSPs) and minimizes board and application specific #ifdefs in drivers.

21 Oct 2010 16:10

<source trunk/include/linux/input/adp5589.h:/i2c_board_info/-EOF c linux-kernel>

Example key-map for an 4×4 matrix as found on the ADP5589 evaluation board.

#include <linux/input/adp5589.h>
static const unsigned short adp5589_keymap[ADP5589_KEYMAPSIZE] = {
	[0]	 = KEY_1,
	[1]	 = KEY_2,
	[2]	 = KEY_3,
	[3]	 = KEY_BACKSPACE,
	[11]	 = KEY_4,
	[12]	 = KEY_5,
	[13]	 = KEY_6,
	[15]	 = KEY_DOT,
	[22]	 = KEY_7,
	[23]	 = KEY_8,
	[24]	 = KEY_9,
	[25]	 = KEY_ESC,
	[55]	 = KEY_UP,
	[56]	 = KEY_0,
	[57]	 = KEY_DOWN,
	[58]	 = KEY_ENTER,
};

Unused row and column pins are exported as general-purpose inputs/outputs to GPIOLIB starting at gpio number 50.

use gpio_start = -1 for dynamic allocation
static const struct adp5589_gpio_platform_data adp5589_gpio_data = {
	.gpio_start = 50,
};

Declare two Input Switch Events (EV_SW), mapped to ROW6 and ROW7.

static const struct adp5589_gpi_map adp5589_gpimap[] = {
	{
		.pin = ADP5589_GPI_PIN_ROW6,
		.sw_evt = SW_KEYPAD_SLIDE,
	},{
		.pin = ADP5589_GPI_PIN_ROW7,
		.sw_evt = SW_CAMERA_LENS_COVER,
	}
};
static struct adp5589_kpad_platform_data adp5589_kpad_data = {
	/* KEYPAD Config */
	.keypad_en_mask	= ADP_COL(0) | ADP_COL(1) | ADP_COL(2) | ADP_COL(3) |
			  ADP_ROW(0) | ADP_ROW(1) | ADP_ROW(2) | ADP_ROW(5),
	.keymap		= adp5589_keymap,
	.keymapsize	= ARRAY_SIZE(adp5589_keymap),
	.repeat		= false,
	.scan_cycle_time = ADP5589_SCAN_CYCLE_10ms,
	/* GPI Switch Event Config */
	.gpimap		= adp5589_gpimap,
	.gpimapsize	= ARRAY_SIZE(adp5589_gpimap),
	/* PULL Config */
	.pullup_en_300k =  ADP_COL(4) | ADP_COL(5) | ADP_COL(6) | ADP_COL(7) |
			   ADP_COL(8) | ADP_COL(9) | ADP_COL(10) |
			   ADP_ROW(3) | ADP_ROW(4) | ADP_ROW(6) | ADP_ROW(7),
	/* GPIO Config */
	.gpio_data = &adp5589_gpio_data,
	/* RESET 1 Config */
	.reset_cfg = RESET_PULSE_WIDTH_10ms | RESET_TRIG_TIME_2000ms | RESET1_POL_LOW,
	.reset1_key_1 = KEY_1,
	.reset1_key_2 = KEY_2,
	.reset1_key_3 = KEY_ESC,
};

Declaring I2C devices

Unlike PCI or USB devices, I2C devices are not enumerated at the hardware level. Instead, the software must know which devices are connected on each I2C bus segment, and what address these devices are using. For this reason, the kernel code must instantiate I2C devices explicitly. There are different ways to achieve this, depending on the context and requirements. However the most common method is to declare the I2C devices by bus number.

This method is appropriate when the I2C bus is a system bus, as in many embedded systems, wherein each I2C bus has a number which is known in advance. It is thus possible to pre-declare the I2C devices that inhabit this bus. This is done with an array of struct i2c_board_info, which is registered by calling i2c_register_board_info().

So, to enable such a driver one need only edit the board support file by adding an appropriate entry to i2c_board_info.

For more information see: Documentation/i2c/instantiating-devices.rst

21 Oct 2010 16:10
ADI part number I2C_BOARD_INFO Name
ADP5589 adp5589-keys
ADP5585-00 adp5585-keys
ADP5585-02 adp5585-02-keys
static struct i2c_board_info __initdata board_i2c_board_info[] = {
#if defined(CONFIG_KEYBOARD_ADP5589) || defined(CONFIG_KEYBOARD_ADP5589_MODULE)
	{
		I2C_BOARD_INFO("adp5589-keys", 0x34),
		.irq = IRQ_PG0,
		.platform_data = &adp5589_kpad_data,
	},
#endif
};
static int __init board_init(void)
{
	[--snip--]
 
	i2c_register_board_info(0, board_i2c_board_info,
				ARRAY_SIZE(board_i2c_board_info));
	[--snip--]
 
	return 0;
}
arch_initcall(board_init);

Adding Linux driver support

Configure kernel with “make menuconfig” (alternatively use “make xconfig” or “make qconfig”)

The ADP5589 Driver depends on CONFIG_I2C

  --- Input Device Support
  <*> Generic input layer (needed for keyboard, mouse, ...)
  < >   Support for memoryless force-feedback devices
  ---   Userland interfaces
  < >   Mouse interface
  < >   Joystick interface
  < >   Touchscreen interface
  <M>   Event interface
  < >   Event debugging
  ---   Input Device Drivers
  [*]   Keyboards  —>

	  --- Keyboards
		< >   ADP5588/87 I2C QWERTY Keypad and IO Expander
		<M>   ADP5589 ADP5585 I2C QWERTY Keypad and IO Expander
		< >   AT keyboard
		< >   Atmel AT42QT1070 Touch Sensor Chip
		< >   Atmel AT42QT2160 Touch Sensor Chip
		< >   DECstation/VAXstation LK201/LK401 keyboard
		< >   GPIO Buttons
		< >   Polled GPIO buttons
		< >   TCA6416/TCA6408A Keypad Support
		< >   GPIO driven matrix keypad support
		< >   Maxim MAX7359 Key Switch Controller
		< >   MELFAS MCS Touchkey
		< >   Freescale MPR121 Touchkey
		< >   Newton keyboard
		< >   OpenCores Keyboard Controller
		< >   Stowaway keyboard
		< >   Sun Type 4 and Type 5 keyboard
		< >   XT keyboard

  [ ]   Mouse  --->
  [ ]   Joysticks  --->
  [ ]   Touchscreens  --->
  [ ]   Miscellaneous devices  --->
      Hardware I/O ports  --->

Hardware configuration

There is no dedicated Blackfin STAMP evaluation board for the ADP5589. During test and driver development we used the ADP5589 Demo Mother/Daughter Board.

It can be easily wired to the Blackfin STAMP TWI/I2C header.

BF537-STAMP (P10) TWI/I2C header ADP5589 Daughter Board
PIN Function PIN/Function
2 (+3.3V) VDD
5 SCL SCL
6 SDA SDA
10 PORTG0 /INT
20 GND GND

Driver testing

Driver loading

root:/> modprobe adp5589_keys
input: adp5589-keys as /devices/platform/i2c-bfin-twi.0/i2c-0/0-0034/input/input0
adp5589_keys 0-0034: Rev.0 keypad, irq 66

Keypad test

root:/> modprobe evdev

Simple event test utility

evtest.c

root:/> event_test /dev/input/event0
Input driver version is 1.0.1
Input device ID: bus 0x18 vendor 0x1 product 0x1 version 0x0
Input device name: "adp5589-keys"
Supported events:
  Event type 0 (Sync)
  Event type 1 (Key)
    Event code 1 (Esc)
    Event code 2 (1)
    Event code 3 (2)
    Event code 4 (3)
    Event code 5 (4)
    Event code 6 (5)
    Event code 7 (6)
    Event code 8 (7)
    Event code 9 (8)
    Event code 10 (9)
    Event code 11 (0)
    Event code 14 (Backspace)
    Event code 28 (Enter)
    Event code 52 (Dot)
    Event code 103 (Up)
    Event code 108 (Down)
  Event type 5 (Switch)
    Event code 9 (?)
    Event code 10 (?)
Testing ... (interrupt to exit)
Event: time 212452.773693, type 1 (Key), code 2 (1), value 1
Event: time 212452.773708, -------------- Report Sync ------------
Event: time 212452.967254, type 1 (Key), code 2 (1), value 0
Event: time 212452.967264, -------------- Report Sync ------------
Event: time 212453.173026, type 1 (Key), code 3 (2), value 1
Event: time 212453.173040, -------------- Report Sync ------------
Event: time 212453.347251, type 1 (Key), code 3 (2), value 0
Event: time 212453.347261, -------------- Report Sync ------------
Event: time 212453.885500, type 1 (Key), code 14 (Backspace), value 1
Event: time 212453.885515, -------------- Report Sync ------------
Event: time 212454.030671, type 1 (Key), code 14 (Backspace), value 0
Event: time 212454.030680, -------------- Report Sync ------------
Event: time 212454.702005, type 1 (Key), code 1 (Esc), value 1
Event: time 212454.702019, -------------- Report Sync ------------
Event: time 212454.876222, type 1 (Key), code 1 (Esc), value 0
Event: time 212454.876232, -------------- Report Sync ------------
Event: time 212455.182126, type 1 (Key), code 28 (Enter), value 1
Event: time 212455.182139, -------------- Report Sync ------------
Event: time 212455.395101, type 1 (Key), code 28 (Enter), value 0
Event: time 212455.395111, -------------- Report Sync ------------
Event: time 212456.614392, type 1 (Key), code 103 (Up), value 1
Event: time 212456.614407, -------------- Report Sync ------------
Event: time 212456.846672, type 1 (Key), code 103 (Up), value 0
Event: time 212456.846683, -------------- Report Sync ------------
Event: time 212459.236095, type 1 (Key), code 28 (Enter), value 1
Event: time 212459.236110, -------------- Report Sync ------------
Event: time 212459.458719, type 1 (Key), code 28 (Enter), value 0
Event: time 212459.458728, -------------- Report Sync ------------
Event: time 212463.264521, type 5 (Switch), code 10 (?), value 1
Event: time 212463.264536, -------------- Report Sync ------------
Event: time 212464.528812, type 5 (Switch), code 10 (?), value 0
Event: time 212464.528823, -------------- Report Sync ------------

GPIO test

In this particular configuration example, GPIO50 will map to ROW3. For more information read GPIO Kernel Documentation

Access using the sysfs interface for userspace

root:/> cd sys/class/gpio/

root:/sys/class/gpio> ls
export      gpiochip0   gpiochip50  unexport

root:/sys/class/gpio> echo 50 > export

root:/sys/class/gpio> ls
export      gpio50      gpiochip0   gpiochip50  unexport

root:/sys/class/gpio> cd gpio50

root:/sys/devices/virtual/gpio/gpio50> ls
active_low  direction   subsystem   uevent      value
root:/sys/devices/virtual/gpio/gpio50> echo low > direction
root:/sys/devices/virtual/gpio/gpio50> echo high > direction

PMOD-IOXP

The PMOD-IOXP is an PMOD board made by Digilent Inc. which features the ADP5589.

The following example shows how to connect the PMOD-IOXP to a Blackfin BF537-STAMP board and a PMOD-KYPD. Also

Hardware configuration

BF537-STAMP (P10) TWI/I2C header PMOD-IOXP
PIN Function PIN/Function
2 (+3.3V) VDD
5 SCL SCL
6 SDA SDA
10 PORTG0 /INT
20 GND GND

Software configuration

#include <linux/input/adp5589.h>
static const unsigned short adp5589_keymap[ADP5589_KEYMAPSIZE] = {
       [ADP5589_KEY(0, 0)]      = KEY_D,
       [ADP5589_KEY(0, 1)]      = KEY_C,
       [ADP5589_KEY(0, 2)]      = KEY_B,
       [ADP5589_KEY(0, 3)]      = KEY_A,
 
       [ADP5589_KEY(1, 0)]      = KEY_E,
       [ADP5589_KEY(1, 1)]      = KEY_9,
       [ADP5589_KEY(1, 2)]      = KEY_6,
       [ADP5589_KEY(1, 3)]      = KEY_3,
 
       [ADP5589_KEY(2, 0)]      = KEY_F,
       [ADP5589_KEY(2, 1)]      = KEY_8,
       [ADP5589_KEY(2, 2)]      = KEY_5,
       [ADP5589_KEY(2, 3)]      = KEY_2,
 
       [ADP5589_KEY(3, 0)]      = KEY_0,
       [ADP5589_KEY(3, 1)]      = KEY_7,
       [ADP5589_KEY(3, 2)]      = KEY_4,
       [ADP5589_KEY(3, 3)]      = KEY_1,
};
 
static struct adp5589_kpad_platform_data adp5589_kpad_data = {
       /* KEYPAD Config */
       .keypad_en_mask = ADP_COL(0) | ADP_COL(1) | ADP_COL(2) | ADP_COL(3) |
                         ADP_ROW(0) | ADP_ROW(1) | ADP_ROW(2) | ADP_ROW(3),
       .keymap         = adp5589_keymap,
       .keymapsize     = ARRAY_SIZE(adp5589_keymap),
       .repeat         = false,
       .scan_cycle_time = ADP5589_SCAN_CYCLE_10ms,
       /* PULL Config */
       .pullup_en_300k =  ADP_COL(4) | ADP_COL(5) | ADP_COL(6) | ADP_COL(7) |
                          ADP_COL(8) | ADP_COL(9) | ADP_COL(10) |
                          ADP_ROW(4) | ADP_ROW(5) | ADP_ROW(6) | ADP_ROW(7),
       /* RESET 1 Config */
       .reset_cfg = RESET_PULSE_WIDTH_10ms | RESET_TRIG_TIME_2000ms | RESET1_POL_LOW,
       .reset1_key_1 = KEY_1,
       .reset1_key_2 = KEY_2,
       .reset1_key_3 = KEY_ESC,
};
 
static struct i2c_board_info __initdata bfin_i2c_board_info[] = {
       {
               I2C_BOARD_INFO("adp5589-keys", 0x34),
               .platform_data = &adp5589_kpad_data,
               .irq = IRQ_PG0,
       },
}

More Information

resources/tools-software/linux-drivers/input-keyboard/adp5589.1346846883.txt.gz · Last modified: 05 Sep 2012 14:08 by Michael Hennerich