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Release 4.7 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/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; }

Contributors

PersonTokensPropCommitsCommitProp
david brownelldavid brownell18685.32%266.67%
dmitry torokhovdmitry torokhov3214.68%133.33%
Total218100.00%3100.00%

/*----------------------------------------------------------------------*/
static int 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 | IRQF_ONESHOT, 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; }

Contributors

PersonTokensPropCommitsCommitProp
david brownelldavid brownell25891.17%240.00%
dmitry torokhovdmitry torokhov238.13%240.00%
lars-peter clausenlars-peter clausen20.71%120.00%
Total283100.00%5100.00%


static int 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; }

Contributors

PersonTokensPropCommitsCommitProp
david brownelldavid brownell4586.54%150.00%
dmitry torokhovdmitry torokhov713.46%150.00%
Total52100.00%2100.00%

/* 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 = dm355evm_keys_remove, .driver = { .name = "dm355evm_keys", }, }; module_platform_driver(dm355evm_keys_driver); MODULE_LICENSE("GPL");

Overall Contributors

PersonTokensPropCommitsCommitProp
david brownelldavid brownell75575.05%225.00%
dmitry torokhovdmitry torokhov24224.06%225.00%
tejun heotejun heo30.30%112.50%
paul gortmakerpaul gortmaker30.30%112.50%
lars-peter clausenlars-peter clausen20.20%112.50%
jj dingjj ding10.10%112.50%
Total1006100.00%8100.00%
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