drivers/hid/hid-picolcd_cir.c

Source file repositories/reference/linux-study-clean/drivers/hid/hid-picolcd_cir.c

File Facts

System
Linux kernel
Corpus path
drivers/hid/hid-picolcd_cir.c
Extension
.c
Size
3979 bytes
Lines
140
Domain
Driver Families
Bucket
drivers/hid
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-only
/***************************************************************************
 *   Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org>  *
 *                                                                         *
 *   Based on Logitech G13 driver (v0.4)                                   *
 *     Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu>   *
 *                                                                         *
 ***************************************************************************/

#include <linux/hid.h>
#include <linux/hid-debug.h>
#include <linux/input.h>
#include "hid-ids.h"

#include <linux/fb.h>
#include <linux/vmalloc.h>
#include <linux/backlight.h>
#include <linux/lcd.h>

#include <linux/leds.h>

#include <linux/seq_file.h>
#include <linux/debugfs.h>

#include <linux/completion.h>
#include <linux/uaccess.h>
#include <linux/module.h>
#include <media/rc-core.h>

#include "hid-picolcd.h"


int picolcd_raw_cir(struct picolcd_data *data,
		struct hid_report *report, u8 *raw_data, int size)
{
	unsigned long flags;
	int i, w, sz;
	struct ir_raw_event rawir = {};

	/* ignore if rc_dev is NULL or status is shunned */
	spin_lock_irqsave(&data->lock, flags);
	if (!data->rc_dev || (data->status & PICOLCD_CIR_SHUN)) {
		spin_unlock_irqrestore(&data->lock, flags);
		return 1;
	}
	spin_unlock_irqrestore(&data->lock, flags);

	/* PicoLCD USB packets contain 16-bit intervals in network order,
	 * with value negated for pulse. Intervals are in microseconds.
	 *
	 * Note: some userspace LIRC code for PicoLCD says negated values
	 * for space - is it a matter of IR chip? (pulse for my TSOP2236)
	 *
	 * In addition, the first interval seems to be around 15000 + base
	 * interval for non-first report of IR data - thus the quirk below
	 * to get RC_CODE to understand Sony and JVC remotes I have at hand
	 */
	sz = size > 0 ? min((int)raw_data[0], size-1) : 0;
	for (i = 0; i+1 < sz; i += 2) {
		w = (raw_data[i] << 8) | (raw_data[i+1]);
		rawir.pulse = !!(w & 0x8000);
		rawir.duration = rawir.pulse ? (65536 - w) : w;
		/* Quirk!! - see above */
		if (i == 0 && rawir.duration > 15000)
			rawir.duration -= 15000;
		ir_raw_event_store(data->rc_dev, &rawir);
	}
	ir_raw_event_handle(data->rc_dev);

	return 1;
}

static int picolcd_cir_open(struct rc_dev *dev)
{
	struct picolcd_data *data = dev->priv;
	unsigned long flags;

	spin_lock_irqsave(&data->lock, flags);
	data->status &= ~PICOLCD_CIR_SHUN;
	spin_unlock_irqrestore(&data->lock, flags);
	return 0;
}

static void picolcd_cir_close(struct rc_dev *dev)
{
	struct picolcd_data *data = dev->priv;
	unsigned long flags;

	spin_lock_irqsave(&data->lock, flags);
	data->status |= PICOLCD_CIR_SHUN;

Annotation

Implementation Notes