--- /dev/null
+/*
+ * $Id: grip_mp.c,v 1.9 2002/07/20 19:28:45 bonnland Exp $
+ *
+ * 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>
+
+MODULE_AUTHOR("Brian Bonnlander");
+MODULE_DESCRIPTION("Gravis Grip Multiport driver");
+#ifdef MODULE_LICENSE
+MODULE_LICENSE("GPL");
+#endif
+EXPORT_NO_SYMBOLS;
+
+#ifdef GRIP_DEBUG
+#define dbg(format, arg...) printk(KERN_ERR __FILE__ ": " format "\n" , ## arg)
+#else
+#define dbg(format, arg...) do {} while (0)
+#endif
+
+/*
+ * Grip multiport state
+ */
+
+struct grip_mp {
+ struct gameport *gameport;
+ struct timer_list timer;
+ struct input_dev dev[4];
+ int mode[4];
+ int registered[4];
+ int used;
+ int reads;
+ int bads;
+
+ /* individual gamepad states */
+ int buttons[4];
+ int xaxes[4];
+ int yaxes[4];
+ int dirty[4]; /* has the state been updated? */
+};
+
+/*
+ * 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_REFRESH_TIME HZ/50 /* 20 ms */
+
+#define GRIP_MODE_NONE 0
+#define GRIP_MODE_RESET 1
+#define GRIP_MODE_GP 2
+#define GRIP_MODE_C64 3
+
+static int grip_btn_gp[] = { BTN_TR, BTN_TL, BTN_A, BTN_B, BTN_C, BTN_X, BTN_Y, BTN_Z, -1 };
+static int grip_btn_c64[] = { BTN_JOYSTICK, -1 };
+
+static int grip_abs_gp[] = { ABS_X, ABS_Y, -1 };
+static int grip_abs_c64[] = { ABS_X, ABS_Y, -1 };
+
+static int *grip_abs[] = { 0, 0, grip_abs_gp, grip_abs_c64 };
+static int *grip_btn[] = { 0, 0, grip_btn_gp, grip_btn_c64 };
+
+static 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 int axis_map[] = { 5, 9, 1, 5, 6, 10, 2, 6, 4, 8, 0, 4, 5, 9, 1, 5 };
+
+/*
+ * 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);
+ portvals = raw_data & 0xf0;
+
+ if (raw_data & 0x31)
+ return IO_RESET;
+ gameport_trigger(gameport);
+
+ if (!poll_until(0x10, 0, 308, gameport, &raw_data))
+ return IO_RESET;
+ } else
+ return IO_RETRY;
+
+ /* Determine packet transfer mode and prepare for packet construction. */
+
+ if (raw_data & 0x20) { /* 3 data bits/read */
+ portvals |= raw_data >> 4; /* Compare B4-B7 before & after trigger */
+
+ if (portvals != 0xb)
+ return 0;
+ data_mask = 7;
+ bits_per_read = 3;
+ pkt = (PACKET_FULL | PACKET_IO_FAST) >> 28;
+ } else { /* 1 data bit/read */
+ data_mask = 1;
+ bits_per_read = 1;
+ pkt = (PACKET_FULL | PACKET_IO_SLOW) >> 28;
+ }
+
+ /* Construct a packet. Final data bits must be zero. */
+
+ while (1) {
+ if (!poll_until(0, 0x10, 77, gameport, &raw_data))
+ return IO_RESET;
+ raw_data = (raw_data >> 5) & data_mask;
+
+ if (pkt & PACKET_FULL)
+ break;
+ pkt = (pkt << bits_per_read) | raw_data;
+
+ if (!poll_until(0x10, 0, 77, gameport, &raw_data))
+ return IO_RESET;
+ }
+
+ if (raw_data)
+ return IO_RESET;
+
+ /* If 3 bits/read used, drop from 30 bits to 28. */
+
+ if (bits_per_read == 3) {
+ pkt = (pkt & 0xffff0000) | ((pkt << 1) & 0xffff);
+ pkt = (pkt >> 2) | 0xf0000000;
+ }
+
+ if (bit_parity(pkt) == 1)
+ return IO_RESET;
+
+ /* Acknowledge packet receipt */
+
+ if (!poll_until(0x30, 0, 77, gameport, &raw_data))
+ return IO_RESET;
+
+ raw_data = gameport_read(gameport);
+
+ if (raw_data & 1)
+ return IO_RESET;
+
+ gameport_trigger(gameport);
+
+ if (!poll_until(0, 0x20, 77, gameport, &raw_data))
+ return IO_RESET;
+
+ /* Return if we just wanted the packet or multiport wants to send more */
+
+ *packet = pkt;
+ if ((sendflags == 0) || ((sendflags & IO_RETRY) && !(pkt & PACKET_MP_DONE)))
+ return IO_GOT_PACKET;
+
+ if (pkt & PACKET_MP_MORE)
+ return IO_GOT_PACKET | IO_RETRY;
+
+ /* Multiport is done sending packets and is ready to receive data */
+
+ if (!poll_until(0x20, 0, 77, gameport, &raw_data))
+ return IO_GOT_PACKET | IO_RESET;
+
+ raw_data = gameport_read(gameport);
+ if (raw_data & 1)
+ return IO_GOT_PACKET | IO_RESET;
+
+ /* Trigger gameport based on bits in sendcode */
+
+ gameport_trigger(gameport);
+ do {
+ if (!poll_until(0x20, 0x10, 116, gameport, &raw_data))
+ return IO_GOT_PACKET | IO_RESET;
+
+ if (!poll_until(0x30, 0, 193, gameport, &raw_data))
+ return IO_GOT_PACKET | IO_RESET;
+
+ if (raw_data & 1)
+ return IO_GOT_PACKET | IO_RESET;
+
+ if (sendcode & 1)
+ gameport_trigger(gameport);
+
+ sendcode >>= 1;
+ } while (sendcode);
+
+ return IO_GOT_PACKET | IO_MODE_FAST;
+}
+
+/*
+ * Disables and restores interrupts for mp_io(), which does the actual I/O.
+ */
+
+static int multiport_io(struct gameport* gameport, int sendflags, int sendcode, u32 *packet)
+{
+ int status;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ status = mp_io(gameport, sendflags, sendcode, packet);
+ local_irq_restore(flags);
+
+ return status;
+}
+
+/*
+ * Puts multiport into digital mode. Multiport LED turns green.
+ *
+ * Returns true if a valid digital packet was received, false otherwise.
+ */
+
+static int dig_mode_start(struct gameport *gameport, u32 *packet)
+{
+ int i, seq_len = sizeof(init_seq)/sizeof(int);
+ int flags, tries = 0, bads = 0;
+
+ for (i = 0; i < seq_len; i++) { /* Send magic sequence */
+ if (init_seq[i])
+ gameport_trigger(gameport);
+ udelay(GRIP_INIT_DELAY);
+ }
+
+ for (i = 0; i < 16; i++) /* Wait for multiport to settle */
+ udelay(GRIP_INIT_DELAY);
+
+ while (tries < 64 && bads < 8) { /* Reset multiport and try getting a packet */
+
+ flags = multiport_io(gameport, IO_RESET, 0x27, packet);
+
+ if (flags & IO_MODE_FAST)
+ return 1;
+
+ if (flags & IO_RETRY)
+ tries++;
+ else
+ bads++;
+ }
+ return 0;
+}
+
+/*
+ * Packet structure: B0-B15 => gamepad state
+ * B16-B20 => gamepad device type
+ * B21-B24 => multiport slot index (1-4)
+ *
+ * Known device types: 0x1f (grip pad), 0x0 (no device). Others may exist.
+ *
+ * Returns the packet status.
+ */
+
+static int get_and_decode_packet(struct grip_mp *grip, int flags)
+{
+ u32 packet;
+ int joytype = 0;
+ int slot = 0;
+ static void register_slot(int i, struct grip_mp *grip);
+
+ /* Get a packet and check for validity */
+
+ flags &= IO_RESET | IO_RETRY;
+ flags = multiport_io(grip->gameport, flags, 0, &packet);
+ grip->reads++;
+
+ if (packet & PACKET_MP_DONE)
+ flags |= IO_DONE;
+
+ if (flags && !(flags & IO_GOT_PACKET)) {
+ grip->bads++;
+ return flags;
+ }
+
+ /* Ignore non-gamepad packets, e.g. multiport hardware version */
+
+ slot = ((packet >> 21) & 0xf) - 1;
+ if ((slot < 0) || (slot > 3))
+ return flags;
+
+ /*
+ * Handle "reset" packets, which occur at startup, and when gamepads
+ * are removed or plugged in. May contain configuration of a new gamepad.
+ */
+
+ joytype = (packet >> 16) & 0x1f;
+ if (!joytype) {
+
+ if (grip->registered[slot]) {
+ printk(KERN_INFO "grip_mp: removing %s, slot %d\n",
+ grip_name[grip->mode[slot]], slot);
+ input_unregister_device(grip->dev + slot);
+ grip->registered[slot] = 0;
+ }
+ dbg("Reset: grip multiport slot %d\n", slot);
+ grip->mode[slot] = GRIP_MODE_RESET;
+ flags |= IO_SLOT_CHANGE;
+ return flags;
+ }
+
+ /* Interpret a grip pad packet */
+
+ if (joytype == 0x1f) {
+
+ int dir = (packet >> 8) & 0xf; /* eight way directional value */
+ grip->buttons[slot] = (~packet) & 0xff;
+ grip->yaxes[slot] = ((axis_map[dir] >> 2) & 3) - 1;
+ grip->xaxes[slot] = (axis_map[dir] & 3) - 1;
+ grip->dirty[slot] = 1;
+
+ if (grip->mode[slot] == GRIP_MODE_RESET)
+ flags |= IO_SLOT_CHANGE;
+
+ grip->mode[slot] = GRIP_MODE_GP;
+
+ if (!grip->registered[slot]) {
+ dbg("New Grip pad in multiport slot %d.\n", slot);
+ register_slot(slot, grip);
+ }
+ return flags;
+ }
+
+ /* Handle non-grip device codes. For now, just print diagnostics. */
+
+ {
+ static int strange_code = 0;
+ if (strange_code != joytype) {
+ printk(KERN_INFO "Possible non-grip pad/joystick detected.\n");
+ printk(KERN_INFO "Got joy type 0x%x and packet 0x%x.\n", joytype, packet);
+ strange_code = joytype;
+ }
+ }
+ return flags;
+}
+
+/*
+ * Returns true if all multiport slot states appear valid.
+ */
+
+static int slots_valid(struct grip_mp *grip)
+{
+ int flags, slot, invalid = 0, active = 0;
+
+ flags = get_and_decode_packet(grip, 0);
+ if (!(flags & IO_GOT_PACKET))
+ return 0;
+
+ for (slot = 0; slot < 4; slot++) {
+ if (grip->mode[slot] == GRIP_MODE_RESET)
+ invalid = 1;
+ if (grip->mode[slot] != GRIP_MODE_NONE)
+ active = 1;
+ }
+
+ /* Return true if no active slot but multiport sent all its data */
+ if (!active)
+ return (flags & IO_DONE) ? 1 : 0;
+
+ /* Return false if invalid device code received */
+ return invalid ? 0 : 1;
+}
+
+/*
+ * Returns whether the multiport was placed into digital mode and
+ * able to communicate its state successfully.
+ */
+
+static int multiport_init(struct grip_mp *grip)
+{
+ int dig_mode, initialized = 0, tries = 0;
+ u32 packet;
+
+ dig_mode = dig_mode_start(grip->gameport, &packet);
+ while (!dig_mode && tries < 4) {
+ dig_mode = dig_mode_start(grip->gameport, &packet);
+ tries++;
+ }
+
+ if (dig_mode)
+ dbg("multiport_init(): digital mode achieved.\n");
+ else {
+ dbg("multiport_init(): unable to achieve digital mode.\n");
+ return 0;
+ }
+
+ /* Get packets, store multiport state, and check state's validity */
+ for (tries = 0; tries < 4096; tries++) {
+ if ( slots_valid(grip) ) {
+ initialized = 1;
+ break;
+ }
+ }
+ dbg("multiport_init(): initialized == %d\n", initialized);
+ return initialized;
+}
+
+/*
+ * Reports joystick state to the linux input layer.
+ */
+
+static void report_slot(struct grip_mp *grip, int slot)
+{
+ struct input_dev *dev = &(grip->dev[slot]);
+ int i, buttons = grip->buttons[slot];
+
+ /* Store button states with linux input driver */
+
+ for (i = 0; i < 8; i++)
+ input_report_key(dev, grip_btn_gp[i], (buttons >> i) & 1);
+
+ /* Store axis states with linux driver */
+
+ input_report_abs(dev, ABS_X, grip->xaxes[slot]);
+ input_report_abs(dev, ABS_Y, grip->yaxes[slot]);
+
+ grip->dirty[slot] = 0;
+}
+
+/*
+ * Get the multiport state.
+ */
+
+static void get_and_report_mp_state(struct grip_mp *grip)
+{
+ int i, npkts, flags;
+
+ for (npkts = 0; npkts < 4; npkts++) {
+ flags = IO_RETRY;
+ for (i = 0; i < 32; i++) {
+ flags = get_and_decode_packet(grip, flags);
+ if ((flags & IO_GOT_PACKET) || !(flags & IO_RETRY))
+ break;
+ }
+ if (flags & IO_DONE)
+ break;
+ }
+
+ for (i = 0; i < 4; i++)
+ if (grip->dirty[i])
+ report_slot(grip, i);
+}
+
+/*
+ * Called when a joystick device file is opened
+ */
+
+static int grip_open(struct input_dev *dev)
+{
+ struct grip_mp *grip = dev->private;
+ if (!grip->used++)
+ mod_timer(&grip->timer, jiffies + GRIP_REFRESH_TIME);
+ return 0;
+}
+
+/*
+ * Called when a joystick device file is closed
+ */
+
+static void grip_close(struct input_dev *dev)
+{
+ struct grip_mp *grip = dev->private;
+ if (!--grip->used)
+ del_timer(&grip->timer);
+}
+
+/*
+ * Tell the linux input layer about a newly plugged-in gamepad.
+ */
+
+static void register_slot(int slot, struct grip_mp *grip)
+{
+ int j, t;
+
+ grip->dev[slot].private = grip;
+ grip->dev[slot].open = grip_open;
+ grip->dev[slot].close = grip_close;
+ grip->dev[slot].name = grip_name[grip->mode[slot]];
+ grip->dev[slot].id.bustype = BUS_GAMEPORT;
+ grip->dev[slot].id.vendor = GAMEPORT_ID_VENDOR_GRAVIS;
+ grip->dev[slot].id.product = 0x0100 + grip->mode[slot];
+ grip->dev[slot].id.version = 0x0100;
+ grip->dev[slot].evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
+
+ for (j = 0; (t = grip_abs[grip->mode[slot]][j]) >= 0; j++) {
+ set_bit(t, grip->dev[slot].absbit);
+ grip->dev[slot].absmin[t] = -1;
+ grip->dev[slot].absmax[t] = 1;
+ }
+
+ for (j = 0; (t = grip_btn[grip->mode[slot]][j]) >= 0; j++)
+ if (t > 0)
+ set_bit(t, grip->dev[slot].keybit);
+
+ input_register_device(grip->dev + slot);
+ grip->registered[slot] = 1;
+
+ if (grip->dirty[slot]) /* report initial state, if any */
+ report_slot(grip, slot);
+
+ printk(KERN_INFO "grip_mp: added %s, slot %d\n",
+ grip_name[grip->mode[slot]], slot);
+}
+
+/*
+ * Repeatedly polls the multiport and generates events.
+ */
+
+static void grip_timer(unsigned long private)
+{
+ struct grip_mp *grip = (void*) private;
+ get_and_report_mp_state(grip);
+ mod_timer(&grip->timer, jiffies + GRIP_REFRESH_TIME);
+}
+
+static void grip_connect(struct gameport *gameport, struct gameport_dev *dev)
+{
+ struct grip_mp *grip;
+
+ if (!(grip = kmalloc(sizeof(struct grip_mp), GFP_KERNEL)))
+ return;
+ memset(grip, 0, sizeof(struct grip_mp));
+ gameport->private = grip;
+ grip->gameport = gameport;
+ init_timer(&grip->timer);
+ grip->timer.data = (long) grip;
+ grip->timer.function = grip_timer;
+
+ if (gameport_open(gameport, dev, GAMEPORT_MODE_RAW))
+ goto fail1;
+ if (!multiport_init(grip))
+ goto fail2;
+ if (!grip->mode[0] && !grip->mode[1] && /* nothing plugged in */
+ !grip->mode[2] && !grip->mode[3])
+ goto fail2;
+ return;
+
+fail2: gameport_close(gameport);
+fail1: kfree(grip);
+}
+
+static void grip_disconnect(struct gameport *gameport)
+{
+ int i;
+
+ struct grip_mp *grip = gameport->private;
+ for (i = 0; i < 4; i++)
+ if (grip->registered[i])
+ input_unregister_device(grip->dev + i);
+ gameport_close(gameport);
+ kfree(grip);
+}
+
+static struct gameport_dev grip_dev = {
+ .connect = grip_connect,
+ .disconnect = grip_disconnect,
+};
+
+static int grip_init(void)
+{
+ gameport_register_device(&grip_dev);
+ return 0;
+}
+
+static void grip_exit(void)
+{
+ gameport_unregister_device(&grip_dev);
+}
+
+module_init(grip_init);
+module_exit(grip_exit);
projects / linux / commitdiff