drivers/input/misc/dm355evm_keys.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * dm355evm_keys.c - support buttons and IR remote on DM355 EVM board
  *
  * Copyright (c) 2008 by David Brownell
  */
 #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/mfd/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;
 };

 /* 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 dm355evm_keys_probe(struct platform_device *pdev)
 {
 	struct dm355evm_keys	*keys;
 	struct input_dev	*input;
 	int			irq;
 	int			error;

 	keys = devm_kzalloc(&pdev->dev, sizeof (*keys), GFP_KERNEL);
 	if (!keys)
 		return -ENOMEM;

 	input = devm_input_allocate_device(&pdev->dev);
 	if (!input)
 		return -ENOMEM;

 	keys->dev = &pdev->dev;
 	keys->input = input;

 	input->name = "DM355 EVM Controls";
 	input->phys = "dm355evm/input0";

 	input->id.bustype = BUS_I2C;
 	input->id.product = 0x0355;
 	input->id.version = dm355evm_msp_read(DM355EVM_MSP_FIRMREV);

 	error = sparse_keymap_setup(input, dm355evm_keys, NULL);
 	if (error)
 		return error;

 	/* REVISIT:  flush the event queue? */

 	/* set up "threaded IRQ handler" */
 	irq = platform_get_irq(pdev, 0);
 	if (irq < 0)
 		return irq;

 	error = devm_request_threaded_irq(&pdev->dev, irq,
 					  NULL, dm355evm_keys_irq,
 					  IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 					  dev_name(&pdev->dev), keys);
 	if (error)
 		return error;

 	/* register */
 	error = input_register_device(input);
 	if (error)
 		return error;

 	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,
 	.driver		= {
 		.name	= "dm355evm_keys",
 	},
 };
 module_platform_driver(dm355evm_keys_driver);

 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* dm355evm_keys.c - support buttons and IR remote on DM355 EVM board
	*
	* Copyright (c) 2008 by David Brownell
	*/
	#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/mfd/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;
	};

	/* 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 dm355evm_keys_probe(struct platform_device *pdev)
	{
	struct dm355evm_keys *keys;
	struct input_dev *input;
	int irq;
	int error;

	keys = devm_kzalloc(&pdev->dev, sizeof (*keys), GFP_KERNEL);
	if (!keys)
	return -ENOMEM;

	input = devm_input_allocate_device(&pdev->dev);
	if (!input)
	return -ENOMEM;

	keys->dev = &pdev->dev;
	keys->input = input;

	input->name = "DM355 EVM Controls";
	input->phys = "dm355evm/input0";

	input->id.bustype = BUS_I2C;
	input->id.product = 0x0355;
	input->id.version = dm355evm_msp_read(DM355EVM_MSP_FIRMREV);

	error = sparse_keymap_setup(input, dm355evm_keys, NULL);
	if (error)
	return error;

	/* REVISIT: flush the event queue? */

	/* set up "threaded IRQ handler" */
	irq = platform_get_irq(pdev, 0);
	if (irq < 0)
	return irq;

	error = devm_request_threaded_irq(&pdev->dev, irq,
	NULL, dm355evm_keys_irq,
	IRQF_TRIGGER_FALLING \| IRQF_ONESHOT,
	dev_name(&pdev->dev), keys);
	if (error)
	return error;

	/* register */
	error = input_register_device(input);
	if (error)
	return error;

	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,
	.driver = {
	.name = "dm355evm_keys",
	},
	};
	module_platform_driver(dm355evm_keys_driver);

	MODULE_LICENSE("GPL");