- 根目录:
- drivers
- input
- misc
- dm355evm_keys.c
/*
* dm355evm_keys.c - support buttons and IR remote on DM355 EVM board
*
* Copyright (c) 2008 by David Brownell
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/input/sparse-keymap.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/i2c/dm355evm_msp.h>
#include <linux/module.h>
/*
* The MSP430 firmware on the DM355 EVM monitors on-board pushbuttons
* and an IR receptor used for the remote control. When any key is
* pressed, or its autorepeat kicks in, an event is sent. This driver
* read those events from the small (32 event) queue and reports them.
*
* Note that physically there can only be one of these devices.
*
* This driver was tested with firmware revision A4.
*/
struct dm355evm_keys {
struct input_dev *input;
struct device *dev;
int irq;
};
/* These initial keycodes can be remapped */
static const struct key_entry dm355evm_keys[] = {
/*
* Pushbuttons on the EVM board ... note that the labels for these
* are SW10/SW11/etc on the PC board. The left/right orientation
* comes only from the firmware's documentation, and presumes the
* power connector is immediately in front of you and the IR sensor
* is to the right. (That is, rotate the board counter-clockwise
* by 90 degrees from the SW10/etc and "DM355 EVM" labels.)
*/
{ KE_KEY, 0x00d8, { KEY_OK } }, /* SW12 */
{ KE_KEY, 0x00b8, { KEY_UP } }, /* SW13 */
{ KE_KEY, 0x00e8, { KEY_DOWN } }, /* SW11 */
{ KE_KEY, 0x0078, { KEY_LEFT } }, /* SW14 */
{ KE_KEY, 0x00f0, { KEY_RIGHT } }, /* SW10 */
/*
* IR buttons ... codes assigned to match the universal remote
* provided with the EVM (Philips PM4S) using DVD code 0020.
*
* These event codes match firmware documentation, but other
* remote controls could easily send more RC5-encoded events.
* The PM4S manual was used in several cases to help select
* a keycode reflecting the intended usage.
*
* RC5 codes are 14 bits, with two start bits (0x3 prefix)
* and a toggle bit (masked out below).
*/
{ KE_KEY, 0x300c, { KEY_POWER } }, /* NOTE: docs omit this */
{ KE_KEY, 0x3000, { KEY_NUMERIC_0 } },
{ KE_KEY, 0x3001, { KEY_NUMERIC_1 } },
{ KE_KEY, 0x3002, { KEY_NUMERIC_2 } },
{ KE_KEY, 0x3003, { KEY_NUMERIC_3 } },
{ KE_KEY, 0x3004, { KEY_NUMERIC_4 } },
{ KE_KEY, 0x3005, { KEY_NUMERIC_5 } },
{ KE_KEY, 0x3006, { KEY_NUMERIC_6 } },
{ KE_KEY, 0x3007, { KEY_NUMERIC_7 } },
{ KE_KEY, 0x3008, { KEY_NUMERIC_8 } },
{ KE_KEY, 0x3009, { KEY_NUMERIC_9 } },
{ KE_KEY, 0x3022, { KEY_ENTER } },
{ KE_KEY, 0x30ec, { KEY_MODE } }, /* "tv/vcr/..." */
{ KE_KEY, 0x300f, { KEY_SELECT } }, /* "info" */
{ KE_KEY, 0x3020, { KEY_CHANNELUP } }, /* "up" */
{ KE_KEY, 0x302e, { KEY_MENU } }, /* "in/out" */
{ KE_KEY, 0x3011, { KEY_VOLUMEDOWN } }, /* "left" */
{ KE_KEY, 0x300d, { KEY_MUTE } }, /* "ok" */
{ KE_KEY, 0x3010, { KEY_VOLUMEUP } }, /* "right" */
{ KE_KEY, 0x301e, { KEY_SUBTITLE } }, /* "cc" */
{ KE_KEY, 0x3021, { KEY_CHANNELDOWN } },/* "down" */
{ KE_KEY, 0x3022, { KEY_PREVIOUS } },
{ KE_KEY, 0x3026, { KEY_SLEEP } },
{ KE_KEY, 0x3172, { KEY_REWIND } }, /* NOTE: docs wrongly say 0x30ca */
{ KE_KEY, 0x3175, { KEY_PLAY } },
{ KE_KEY, 0x3174, { KEY_FASTFORWARD } },
{ KE_KEY, 0x3177, { KEY_RECORD } },
{ KE_KEY, 0x3176, { KEY_STOP } },
{ KE_KEY, 0x3169, { KEY_PAUSE } },
};
/*
* Because we communicate with the MSP430 using I2C, and all I2C calls
* in Linux sleep, we use a threaded IRQ handler. The IRQ itself is
* active low, but we go through the GPIO controller so we can trigger
* on falling edges and not worry about enabling/disabling the IRQ in
* the keypress handling path.
*/
static irqreturn_t dm355evm_keys_irq(int irq, void *_keys)
{
static u16 last_event;
struct dm355evm_keys *keys = _keys;
const struct key_entry *ke;
unsigned int keycode;
int status;
u16 event;
/* For simplicity we ignore INPUT_COUNT and just read
* events until we get the "queue empty" indicator.
* Reading INPUT_LOW decrements the count.
*/
for (;;) {
status = dm355evm_msp_read(DM355EVM_MSP_INPUT_HIGH);
if (status < 0) {
dev_dbg(keys->dev, "input high err %d\n",
status);
break;
}
event = status << 8;
status = dm355evm_msp_read(DM355EVM_MSP_INPUT_LOW);
if (status < 0) {
dev_dbg(keys->dev, "input low err %d\n",
status);
break;
}
event |= status;
if (event == 0xdead)
break;
/* Press and release a button: two events, same code.
* Press and hold (autorepeat), then release: N events
* (N > 2), same code. For RC5 buttons the toggle bits
* distinguish (for example) "1-autorepeat" from "1 1";
* but PCB buttons don't support that bit.
*
* So we must synthesize release events. We do that by
* mapping events to a press/release event pair; then
* to avoid adding extra events, skip the second event
* of each pair.
*/
if (event == last_event) {
last_event = 0;
continue;
}
last_event = event;
/* ignore the RC5 toggle bit */
event &= ~0x0800;
/* find the key, or report it as unknown */
ke = sparse_keymap_entry_from_scancode(keys->input, event);
keycode = ke ? ke->keycode : KEY_UNKNOWN;
dev_dbg(keys->dev,
"input event 0x%04x--> keycode %d\n",
event, keycode);
/* report press + release */
input_report_key(keys->input, keycode, 1);
input_sync(keys->input);
input_report_key(keys->input, keycode, 0);
input_sync(keys->input);
}
return IRQ_HANDLED;
}
/*----------------------------------------------------------------------*/
static int __devinit dm355evm_keys_probe(struct platform_device *pdev)
{
struct dm355evm_keys *keys;
struct input_dev *input;
int status;
/* allocate instance struct and input dev */
keys = kzalloc(sizeof *keys, GFP_KERNEL);
input = input_allocate_device();
if (!keys || !input) {
status = -ENOMEM;
goto fail1;
}
keys->dev = &pdev->dev;
keys->input = input;
/* set up "threaded IRQ handler" */
status = platform_get_irq(pdev, 0);
if (status < 0)
goto fail1;
keys->irq = status;
input_set_drvdata(input, keys);
input->name = "DM355 EVM Controls";
input->phys = "dm355evm/input0";
input->dev.parent = &pdev->dev;
input->id.bustype = BUS_I2C;
input->id.product = 0x0355;
input->id.version = dm355evm_msp_read(DM355EVM_MSP_FIRMREV);
status = sparse_keymap_setup(input, dm355evm_keys, NULL);
if (status)
goto fail1;
/* REVISIT: flush the event queue? */
status = request_threaded_irq(keys->irq, NULL, dm355evm_keys_irq,
IRQF_TRIGGER_FALLING, dev_name(&pdev->dev), keys);
if (status < 0)
goto fail2;
/* register */
status = input_register_device(input);
if (status < 0)
goto fail3;
platform_set_drvdata(pdev, keys);
return 0;
fail3:
free_irq(keys->irq, keys);
fail2:
sparse_keymap_free(input);
fail1:
input_free_device(input);
kfree(keys);
dev_err(&pdev->dev, "can't register, err %d\n", status);
return status;
}
static int __devexit dm355evm_keys_remove(struct platform_device *pdev)
{
struct dm355evm_keys *keys = platform_get_drvdata(pdev);
free_irq(keys->irq, keys);
sparse_keymap_free(keys->input);
input_unregister_device(keys->input);
kfree(keys);
return 0;
}
/* REVISIT: add suspend/resume when DaVinci supports it. The IRQ should
* be able to wake up the system. When device_may_wakeup(&pdev->dev), call
* enable_irq_wake() on suspend, and disable_irq_wake() on resume.
*/
/*
* I2C is used to talk to the MSP430, but this platform device is
* exposed by an MFD driver that manages I2C communications.
*/
static struct platform_driver dm355evm_keys_driver = {
.probe = dm355evm_keys_probe,
.remove = __devexit_p(dm355evm_keys_remove),
.driver = {
.owner = THIS_MODULE,
.name = "dm355evm_keys",
},
};
module_platform_driver(dm355evm_keys_driver);
MODULE_LICENSE("GPL");