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Release 4.11 drivers/input/joystick/analog.c

/*
 *  Copyright (c) 1996-2001 Vojtech Pavlik
 */

/*
 * Analog joystick and gamepad driver for Linux
 */

/*
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 * Should you need to contact me, the author, you can do so either by
 * e-mail - mail your message to <vojtech@ucw.cz>, or by paper mail:
 * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
 */

#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/bitops.h>
#include <linux/init.h>
#include <linux/input.h>
#include <linux/gameport.h>
#include <linux/jiffies.h>
#include <linux/timex.h>
#include <linux/timekeeping.h>


#define DRIVER_DESC	"Analog joystick and gamepad driver"

MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");


static bool use_ktime = true;
module_param(use_ktime, bool, 0400);
MODULE_PARM_DESC(use_ktime, "Use ktime for measuring I/O speed");

/*
 * Option parsing.
 */


#define ANALOG_PORTS		16


static char *js[ANALOG_PORTS];

static unsigned int js_nargs;

static int analog_options[ANALOG_PORTS];
module_param_array_named(map, js, charp, &js_nargs, 0);
MODULE_PARM_DESC(map, "Describes analog joysticks type/capabilities");

/*
 * Times, feature definitions.
 */


#define ANALOG_RUDDER		0x00004

#define ANALOG_THROTTLE		0x00008

#define ANALOG_AXES_STD		0x0000f

#define ANALOG_BTNS_STD		0x000f0


#define ANALOG_BTNS_CHF		0x00100

#define ANALOG_HAT1_CHF		0x00200

#define ANALOG_HAT2_CHF		0x00400

#define ANALOG_HAT_FCS		0x00800

#define ANALOG_HATS_ALL		0x00e00

#define ANALOG_BTN_TL		0x01000

#define ANALOG_BTN_TR		0x02000

#define ANALOG_BTN_TL2		0x04000

#define ANALOG_BTN_TR2		0x08000

#define ANALOG_BTNS_TLR		0x03000

#define ANALOG_BTNS_TLR2	0x0c000

#define ANALOG_BTNS_GAMEPAD	0x0f000


#define ANALOG_HBTN_CHF		0x10000

#define ANALOG_ANY_CHF		0x10700

#define ANALOG_SAITEK		0x20000

#define ANALOG_EXTENSIONS	0x7ff00

#define ANALOG_GAMEPAD		0x80000


#define ANALOG_MAX_TIME		3	
/* 3 ms */

#define ANALOG_LOOP_TIME	2000	
/* 2 * loop */

#define ANALOG_SAITEK_DELAY	200	
/* 200 us */

#define ANALOG_SAITEK_TIME	2000	
/* 2000 us */

#define ANALOG_AXIS_TIME	2	
/* 2 * refresh */

#define ANALOG_INIT_RETRIES	8	
/* 8 times */

#define ANALOG_FUZZ_BITS	2	
/* 2 bit more */

#define ANALOG_FUZZ_MAGIC	36	
/* 36 u*ms/loop */


#define ANALOG_MAX_NAME_LENGTH  128

#define ANALOG_MAX_PHYS_LENGTH	32


static short analog_axes[] = { ABS_X, ABS_Y, ABS_RUDDER, ABS_THROTTLE };

static short analog_hats[] = { ABS_HAT0X, ABS_HAT0Y, ABS_HAT1X, ABS_HAT1Y, ABS_HAT2X, ABS_HAT2Y };

static short analog_pads[] = { BTN_Y, BTN_Z, BTN_TL, BTN_TR };

static short analog_exts[] = { ANALOG_HAT1_CHF, ANALOG_HAT2_CHF, ANALOG_HAT_FCS };

static short analog_pad_btn[] = { BTN_A, BTN_B, BTN_C, BTN_X, BTN_TL2, BTN_TR2, BTN_SELECT, BTN_START, BTN_MODE, BTN_BASE };

static short analog_joy_btn[] = { BTN_TRIGGER, BTN_THUMB, BTN_TOP, BTN_TOP2, BTN_BASE, BTN_BASE2,
				  BTN_BASE3, BTN_BASE4, BTN_BASE5, BTN_BASE6 };


static unsigned char analog_chf[] = { 0xf, 0x0, 0x1, 0x9, 0x2, 0x4, 0xc, 0x8, 0x3, 0x5, 0xb, 0x7, 0xd, 0xe, 0xa, 0x6 };


struct analog {
	
struct input_dev *dev;
	
int mask;
	
short *buttons;
	
char name[ANALOG_MAX_NAME_LENGTH];
	
char phys[ANALOG_MAX_PHYS_LENGTH];
};


struct analog_port {
	
struct gameport *gameport;
	
struct analog analog[2];
	
unsigned char mask;
	
char saitek;
	
char cooked;
	
int bads;
	
int reads;
	
int speed;
	
int loop;
	
int fuzz;
	
int axes[4];
	
int buttons;
	
int initial[4];
	
int axtime;
};

/*
 * Time macros.
 */

#ifdef __i386__

#include <linux/i8253.h>


#define GET_TIME(x)	do { if (boot_cpu_has(X86_FEATURE_TSC)) x = (unsigned int)rdtsc(); else x = get_time_pit(); } while (0)

#define DELTA(x,y)	(boot_cpu_has(X86_FEATURE_TSC) ? ((y) - (x)) : ((x) - (y) + ((x) < (y) ? PIT_TICK_RATE / HZ : 0)))

#define TIME_NAME	(boot_cpu_has(X86_FEATURE_TSC)?"TSC":"PIT")

static unsigned int get_time_pit(void) { unsigned long flags; unsigned int count; raw_spin_lock_irqsave(&i8253_lock, flags); outb_p(0x00, 0x43); count = inb_p(0x40); count |= inb_p(0x40) << 8; raw_spin_unlock_irqrestore(&i8253_lock, flags); return count; }

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Vojtech Pavlik5796.61%150.00%
Thomas Gleixner23.39%150.00%
Total59100.00%2100.00%

#elif defined(__x86_64__) #define GET_TIME(x) do { x = (unsigned int)rdtsc(); } while (0) #define DELTA(x,y) ((y)-(x)) #define TIME_NAME "TSC" #elif defined(__alpha__) || defined(CONFIG_MN10300) || defined(CONFIG_ARM) || defined(CONFIG_ARM64) || defined(CONFIG_TILE) #define GET_TIME(x) do { x = get_cycles(); } while (0) #define DELTA(x,y) ((y)-(x)) #define TIME_NAME "get_cycles" #else #define FAKE_TIME static unsigned long analog_faketime = 0; #define GET_TIME(x) do { x = analog_faketime++; } while(0) #define DELTA(x,y) ((y)-(x)) #define TIME_NAME "Unreliable" #warning Precise timer not defined for this architecture. #endif
static inline u64 get_time(void) { if (use_ktime) { return ktime_get_ns(); } else { unsigned int x; GET_TIME(x); return x; } }

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static inline unsigned int delta(u64 x, u64 y) { if (use_ktime) return y - x; else return DELTA((unsigned int)x, (unsigned int)y); }

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Takashi Iwai40100.00%1100.00%
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/* * analog_decode() decodes analog joystick data and reports input events. */
static void analog_decode(struct analog *analog, int *axes, int *initial, int buttons) { struct input_dev *dev = analog->dev; int i, j; if (analog->mask & ANALOG_HAT_FCS) for (i = 0; i < 4; i++) if (axes[3] < ((initial[3] * ((i << 1) + 1)) >> 3)) { buttons |= 1 << (i + 14); break; } for (i = j = 0; i < 6; i++) if (analog->mask & (0x10 << i)) input_report_key(dev, analog->buttons[j++], (buttons >> i) & 1); if (analog->mask & ANALOG_HBTN_CHF) for (i = 0; i < 4; i++) input_report_key(dev, analog->buttons[j++], (buttons >> (i + 10)) & 1); if (analog->mask & ANALOG_BTN_TL) input_report_key(dev, analog_pads[0], axes[2] < (initial[2] >> 1)); if (analog->mask & ANALOG_BTN_TR) input_report_key(dev, analog_pads[1], axes[3] < (initial[3] >> 1)); if (analog->mask & ANALOG_BTN_TL2) input_report_key(dev, analog_pads[2], axes[2] > (initial[2] + (initial[2] >> 1))); if (analog->mask & ANALOG_BTN_TR2) input_report_key(dev, analog_pads[3], axes[3] > (initial[3] + (initial[3] >> 1))); for (i = j = 0; i < 4; i++) if (analog->mask & (1 << i)) input_report_abs(dev, analog_axes[j++], axes[i]); for (i = j = 0; i < 3; i++) if (analog->mask & analog_exts[i]) { input_report_abs(dev, analog_hats[j++], ((buttons >> ((i << 2) + 7)) & 1) - ((buttons >> ((i << 2) + 9)) & 1)); input_report_abs(dev, analog_hats[j++], ((buttons >> ((i << 2) + 8)) & 1) - ((buttons >> ((i << 2) + 6)) & 1)); } input_sync(dev); }

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Linus Torvalds (pre-git)49999.01%150.00%
Vojtech Pavlik50.99%150.00%
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/* * analog_cooked_read() reads analog joystick data. */
static int analog_cooked_read(struct analog_port *port) { struct gameport *gameport = port->gameport; u64 time[4], start, loop, now; unsigned int loopout, timeout; unsigned char data[4], this, last; unsigned long flags; int i, j; loopout = (ANALOG_LOOP_TIME * port->loop) / 1000; timeout = ANALOG_MAX_TIME * port->speed; local_irq_save(flags); gameport_trigger(gameport); now = get_time(); local_irq_restore(flags); start = now; this = port->mask; i = 0; do { loop = now; last = this; local_irq_disable(); this = gameport_read(gameport) & port->mask; now = get_time(); local_irq_restore(flags); if ((last ^ this) && (delta(loop, now) < loopout)) { data[i] = last ^ this; time[i] = now; i++; } } while (this && (i < 4) && (delta(start, now) < timeout)); this <<= 4; for (--i; i >= 0; i--) { this |= data[i]; for (j = 0; j < 4; j++) if (data[i] & (1 << j)) port->axes[j] = (delta(start, time[i]) << ANALOG_FUZZ_BITS) / port->loop; } return -(this != port->mask); }

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Linus Torvalds (pre-git)27894.24%125.00%
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static int analog_button_read(struct analog_port *port, char saitek, char chf) { unsigned char u; int t = 1, i = 0; int strobe = gameport_time(port->gameport, ANALOG_SAITEK_TIME); u = gameport_read(port->gameport); if (!chf) { port->buttons = (~u >> 4) & 0xf; return 0; } port->buttons = 0; while ((~u & 0xf0) && (i < 16) && t) { port->buttons |= 1 << analog_chf[(~u >> 4) & 0xf]; if (!saitek) return 0; udelay(ANALOG_SAITEK_DELAY); t = strobe; gameport_trigger(port->gameport); while (((u = gameport_read(port->gameport)) & port->mask) && t) t--; i++; } return -(!t || (i == 16)); }

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/* * analog_poll() repeatedly polls the Analog joysticks. */
static void analog_poll(struct gameport *gameport) { struct analog_port *port = gameport_get_drvdata(gameport); int i; char saitek = !!(port->analog[0].mask & ANALOG_SAITEK); char chf = !!(port->analog[0].mask & ANALOG_ANY_CHF); if (port->cooked) { port->bads -= gameport_cooked_read(port->gameport, port->axes, &port->buttons); if (chf) port->buttons = port->buttons ? (1 << analog_chf[port->buttons]) : 0; port->reads++; } else { if (!port->axtime--) { port->bads -= analog_cooked_read(port); port->bads -= analog_button_read(port, saitek, chf); port->reads++; port->axtime = ANALOG_AXIS_TIME - 1; } else { if (!saitek) analog_button_read(port, saitek, chf); } } for (i = 0; i < 2; i++) if (port->analog[i].mask) analog_decode(port->analog + i, port->axes, port->initial, port->buttons); }

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Linus Torvalds (pre-git)21996.05%150.00%
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/* * analog_open() is a callback from the input open routine. */
static int analog_open(struct input_dev *dev) { struct analog_port *port = input_get_drvdata(dev); gameport_start_polling(port->gameport); return 0; }

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/* * analog_close() is a callback from the input close routine. */
static void analog_close(struct input_dev *dev) { struct analog_port *port = input_get_drvdata(dev); gameport_stop_polling(port->gameport); }

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/* * analog_calibrate_timer() calibrates the timer and computes loop * and timeout values for a joystick port. */
static void analog_calibrate_timer(struct analog_port *port) { struct gameport *gameport = port->gameport; unsigned int i, t, tx; u64 t1, t2, t3; unsigned long flags; if (use_ktime) { port->speed = 1000000; } else { local_irq_save(flags); t1 = get_time(); #ifdef FAKE_TIME analog_faketime += 830; #endif mdelay(1); t2 = get_time(); t3 = get_time(); local_irq_restore(flags); port->speed = delta(t1, t2) - delta(t2, t3); } tx = ~0; for (i = 0; i < 50; i++) { local_irq_save(flags); t1 = get_time(); for (t = 0; t < 50; t++) { gameport_read(gameport); t2 = get_time(); } t3 = get_time(); local_irq_restore(flags); udelay(i); t = delta(t1, t2) - delta(t2, t3); if (t < tx) tx = t; } port->loop = tx / 50; }

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Linus Torvalds (pre-git)17079.07%125.00%
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Vojtech Pavlik62.79%250.00%
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/* * analog_name() constructs a name for an analog joystick. */
static void analog_name(struct analog *analog) { snprintf(analog->name, sizeof(analog->name), "Analog %d-axis %d-button", hweight8(analog->mask & ANALOG_AXES_STD), hweight8(analog->mask & ANALOG_BTNS_STD) + !!(analog->mask & ANALOG_BTNS_CHF) * 2 + hweight16(analog->mask & ANALOG_BTNS_GAMEPAD) + !!(analog->mask & ANALOG_HBTN_CHF) * 4); if (analog->mask & ANALOG_HATS_ALL) snprintf(analog->name, sizeof(analog->name), "%s %d-hat", analog->name, hweight16(analog->mask & ANALOG_HATS_ALL)); if (analog->mask & ANALOG_HAT_FCS) strlcat(analog->name, " FCS", sizeof(analog->name)); if (analog->mask & ANALOG_ANY_CHF) strlcat(analog->name, (analog->mask & ANALOG_SAITEK) ? " Saitek" : " CHF", sizeof(analog->name)); strlcat(analog->name, (analog->mask & ANALOG_GAMEPAD) ? " gamepad": " joystick", sizeof(analog->name)); }

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/* * analog_init_device() */
static int analog_init_device(struct analog_port *port, struct analog *analog, int index) { struct input_dev *input_dev; int i, j, t, v, w, x, y, z; int error; analog_name(analog); snprintf(analog->phys, sizeof(analog->phys), "%s/input%d", port->gameport->phys, index); analog->buttons = (analog->mask & ANALOG_GAMEPAD) ? analog_pad_btn : analog_joy_btn; analog->dev = input_dev = input_allocate_device(); if (!input_dev) return -ENOMEM; input_dev->name = analog->name; input_dev->phys = analog->phys; input_dev->id.bustype = BUS_GAMEPORT; input_dev->id.vendor = GAMEPORT_ID_VENDOR_ANALOG; input_dev->id.product = analog->mask >> 4; input_dev->id.version = 0x0100; input_dev->dev.parent = &port->gameport->dev; input_set_drvdata(input_dev, port); input_dev->open = analog_open; input_dev->close = analog_close; input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); for (i = j = 0; i < 4; i++) if (analog->mask & (1 << i)) { t = analog_axes[j]; x = port->axes[i]; y = (port->axes[0] + port->axes[1]) >> 1; z = y - port->axes[i]; z = z > 0 ? z : -z; v = (x >> 3); w = (x >> 3); if ((i == 2 || i == 3) && (j == 2 || j == 3) && (z > (y >> 3))) x = y; if (analog->mask & ANALOG_SAITEK) { if (i == 2) x = port->axes[i]; v = x - (x >> 2); w = (x >> 4); } input_set_abs_params(input_dev, t, v, (x << 1) - v, port->fuzz, w); j++; } for (i = j = 0; i < 3; i++) if (analog->mask & analog_exts[i]) for (x = 0; x < 2; x++) { t = analog_hats[j++]; input_set_abs_params(input_dev, t, -1, 1, 0, 0); } for (i = j = 0; i < 4; i++) if (analog->mask & (0x10 << i)) set_bit(analog->buttons[j++], input_dev->keybit); if (analog->mask & ANALOG_BTNS_CHF) for (i = 0; i < 2; i++) set_bit(analog->buttons[j++], input_dev->keybit); if (analog->mask & ANALOG_HBTN_CHF) for (i =