drivers/input/joystick/joydump.c

Source file repositories/reference/linux-study-clean/drivers/input/joystick/joydump.c

File Facts

System
Linux kernel
Corpus path
drivers/input/joystick/joydump.c
Extension
.c
Size
3287 bytes
Lines
143
Domain
Driver Families
Bucket
drivers/input
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

struct joydump {
	unsigned int time;
	unsigned char data;
};

static int joydump_connect(struct gameport *gameport, struct gameport_driver *drv)
{
	struct joydump *buf;	/* all entries */
	struct joydump *dump, *prev;	/* one entry each */
	int axes[4], buttons;
	int i, j, t, timeout;
	unsigned long flags;
	unsigned char u;

	printk(KERN_INFO "joydump: ,------------------ START ----------------.\n");
	printk(KERN_INFO "joydump: | Dumping: %30s |\n", gameport->phys);
	printk(KERN_INFO "joydump: | Speed: %28d kHz |\n", gameport->speed);

	if (gameport_open(gameport, drv, GAMEPORT_MODE_RAW)) {

		printk(KERN_INFO "joydump: | Raw mode not available - trying cooked.    |\n");

		if (gameport_open(gameport, drv, GAMEPORT_MODE_COOKED)) {

			printk(KERN_INFO "joydump: | Cooked not available either. Failing.   |\n");
			printk(KERN_INFO "joydump: `------------------- END -----------------'\n");
			return -ENODEV;
		}

		gameport_cooked_read(gameport, axes, &buttons);

		for (i = 0; i < 4; i++)
			printk(KERN_INFO "joydump: | Axis %d: %4d.                           |\n", i, axes[i]);
		printk(KERN_INFO "joydump: | Buttons %02x.                             |\n", buttons);
		printk(KERN_INFO "joydump: `------------------- END -----------------'\n");
	}

	timeout = gameport_time(gameport, 10000); /* 10 ms */

	buf = kmalloc_objs(struct joydump, BUF_SIZE);
	if (!buf) {
		printk(KERN_INFO "joydump: no memory for testing\n");
		goto jd_end;
	}
	dump = buf;
	t = 0;
	i = 1;

	local_irq_save(flags);

	u = gameport_read(gameport);

	dump->data = u;
	dump->time = t;
	dump++;

	gameport_trigger(gameport);

	while (i < BUF_SIZE && t < timeout) {

		dump->data = gameport_read(gameport);

		if (dump->data ^ u) {
			u = dump->data;
			dump->time = t;
			i++;
			dump++;
		}
		t++;
	}

	local_irq_restore(flags);

/*
 * Dump data.
 */

	t = i;
	dump = buf;
	prev = dump;

	printk(KERN_INFO "joydump: >------------------ DATA -----------------<\n");
	printk(KERN_INFO "joydump: | index: %3d delta: %3d us data: ", 0, 0);
	for (j = 7; j >= 0; j--)
		printk("%d", (dump->data >> j) & 1);
	printk(" |\n");
	dump++;

	for (i = 1; i < t; i++, dump++, prev++) {
		printk(KERN_INFO "joydump: | index: %3d delta: %3d us data: ",

Annotation

Implementation Notes