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/*
* Driver for the Gravis Grip Multiport, a gamepad "hub" that
* connects up to four 9-pin digital gamepads/joysticks.
* Driver tested on SMP and UP kernel versions 2.4.18-4 and 2.4.18-5.
*
* Thanks to Chris Gassib for helpful advice.
*
* Copyright (c) 2002 Brian Bonnlander, Bill Soudan
* Copyright (c) 1998-2000 Vojtech Pavlik
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/gameport.h>
#include <linux/input.h>
#include <linux/delay.h>
#include <linux/proc_fs.h>
#include <linux/jiffies.h>
#define DRIVER_DESC "Gravis Grip Multiport driver"
MODULE_AUTHOR("Brian Bonnlander");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
#ifdef GRIP_DEBUG
#define dbg(format, arg...) printk(KERN_ERR __FILE__ ": " format "\n" , ## arg)
#else
#define dbg(format, arg...) do {} while (0)
#endif
#define GRIP_MAX_PORTS 4
/*
* Grip multiport state
*/
struct grip_port {
struct input_dev *dev;
int mode;
int registered;
/* individual gamepad states */
int buttons;
int xaxes;
int yaxes;
int dirty; /* has the state been updated? */
};
struct grip_mp {
struct gameport *gameport;
struct grip_port *port[GRIP_MAX_PORTS];
int reads;
int bads;
};
/*
* Multiport packet interpretation
*/
#define PACKET_FULL 0x80000000 /* packet is full */
#define PACKET_IO_FAST 0x40000000 /* 3 bits per gameport read */
#define PACKET_IO_SLOW 0x20000000 /* 1 bit per gameport read */
#define PACKET_MP_MORE 0x04000000 /* multiport wants to send more */
#define PACKET_MP_DONE 0x02000000 /* multiport done sending */
/*
* Packet status code interpretation
*/
#define IO_GOT_PACKET 0x0100 /* Got a packet */
#define IO_MODE_FAST 0x0200 /* Used 3 data bits per gameport read */
#define IO_SLOT_CHANGE 0x0800 /* Multiport physical slot status changed */
#define IO_DONE 0x1000 /* Multiport is done sending packets */
#define IO_RETRY 0x4000 /* Try again later to get packet */
#define IO_RESET 0x8000 /* Force multiport to resend all packets */
/*
* Gamepad configuration data. Other 9-pin digital joystick devices
* may work with the multiport, so this may not be an exhaustive list!
* Commodore 64 joystick remains untested.
*/
#define GRIP_INIT_DELAY 2000 /* 2 ms */
#define GRIP_MODE_NONE 0
#define GRIP_MODE_RESET 1
#define GRIP_MODE_GP 2
#define GRIP_MODE_C64 3
static const int grip_btn_gp[] = { BTN_TR, BTN_TL, BTN_A, BTN_B, BTN_C, BTN_X, BTN_Y, BTN_Z, -1 };
static const int grip_btn_c64[] = { BTN_JOYSTICK, -1 };
static const int grip_abs_gp[] = { ABS_X, ABS_Y, -1 };
static const int grip_abs_c64[] = { ABS_X, ABS_Y, -1 };
static const int *grip_abs[] = { NULL, NULL, grip_abs_gp, grip_abs_c64 };
static const int *grip_btn[] = { NULL, NULL, grip_btn_gp, grip_btn_c64 };
static const char *grip_name[] = { NULL, NULL, "Gravis Grip Pad", "Commodore 64 Joystick" };
static const int init_seq[] = {
1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1,
1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1,
1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1,
0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1 };
/* Maps multiport directional values to X,Y axis values (each axis encoded in 3 bits) */
static const int axis_map[] = { 5, 9, 1, 5, 6, 10, 2, 6, 4, 8, 0, 4, 5, 9, 1, 5 };
static int register_slot(int i, struct grip_mp *grip);
/*
* Returns whether an odd or even number of bits are on in pkt.
*/
static int bit_parity(u32 pkt)
{
int x = pkt ^ (pkt >> 16);
x ^= x >> 8;
x ^= x >> 4;
x ^= x >> 2;
x ^= x >> 1;
return x & 1;
}
/*
* Poll gameport; return true if all bits set in 'onbits' are on and
* all bits set in 'offbits' are off.
*/
static inline int poll_until(u8 onbits, u8 offbits, int u_sec, struct gameport* gp, u8 *data)
{
int i, nloops;
nloops = gameport_time(gp, u_sec);
for (i = 0; i < nloops; i++) {
*data = gameport_read(gp);
if ((*data & onbits) == onbits &&
(~(*data) & offbits) == offbits)
return 1;
}
dbg("gameport timed out after %d microseconds.\n", u_sec);
return 0;
}
/*
* Gets a 28-bit packet from the multiport.
*
* After getting a packet successfully, commands encoded by sendcode may
* be sent to the multiport.
*
* The multiport clock value is reflected in gameport bit B4.
*
* Returns a packet status code indicating whether packet is valid, the transfer
* mode, and any error conditions.
*
* sendflags: current I/O status
* sendcode: data to send to the multiport if sendflags is nonzero
*/
static int mp_io(struct gameport* gameport, int sendflags, int sendcode, u32 *packet)
{
u8 raw_data; /* raw data from gameport */
u8 data_mask; /* packet data bits from raw_data */
u32 pkt; /* packet temporary storage */
int bits_per_read; /* num packet bits per gameport read */
int portvals = 0; /* used for port value sanity check */
int i;
/* Gameport bits B0, B4, B5 should first be off, then B4 should come on. */
*packet = 0;
raw_data = gameport_read(gameport);
if (raw_data & 1)
return IO_RETRY;
for (i = 0; i < 64; i++) {
raw_data = gameport_read(gameport);
portvals |= 1 << ((raw_data >> 4) & 3); /* Demux B4, B5 */
}
if (portvals == 1) { /* B4, B5 off */
raw_data = gameport_read(gameport
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