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v3.15
 
   1/*
   2 *   serial.c
   3 *   Copyright (c) by Jaroslav Kysela <perex@perex.cz>,
   4 *                    Isaku Yamahata <yamahata@private.email.ne.jp>,
   5 *		      George Hansper <ghansper@apana.org.au>,
   6 *		      Hannu Savolainen
   7 *
   8 *   This code is based on the code from ALSA 0.5.9, but heavily rewritten.
   9 *
  10 *   This program is free software; you can redistribute it and/or modify
  11 *   it under the terms of the GNU General Public License as published by
  12 *   the Free Software Foundation; either version 2 of the License, or
  13 *   (at your option) any later version.
  14 *
  15 *   This program is distributed in the hope that it will be useful,
  16 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 *   GNU General Public License for more details.
  19 *
  20 *   You should have received a copy of the GNU General Public License
  21 *   along with this program; if not, write to the Free Software
  22 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  23 *
  24 * Sat Mar 31 17:27:57 PST 2001 tim.mann@compaq.com 
  25 *      Added support for the Midiator MS-124T and for the MS-124W in
  26 *      Single Addressed (S/A) or Multiple Burst (M/B) mode, with
  27 *      power derived either parasitically from the serial port or
  28 *      from a separate power supply.
  29 *
  30 *      More documentation can be found in serial-u16550.txt.
  31 */
  32
  33#include <linux/init.h>
  34#include <linux/interrupt.h>
  35#include <linux/err.h>
  36#include <linux/platform_device.h>
  37#include <linux/slab.h>
  38#include <linux/ioport.h>
  39#include <linux/module.h>
 
  40#include <sound/core.h>
  41#include <sound/rawmidi.h>
  42#include <sound/initval.h>
  43
  44#include <linux/serial_reg.h>
  45#include <linux/jiffies.h>
  46
  47#include <asm/io.h>
  48
  49MODULE_DESCRIPTION("MIDI serial u16550");
  50MODULE_LICENSE("GPL");
  51MODULE_SUPPORTED_DEVICE("{{ALSA, MIDI serial u16550}}");
  52
  53#define SNDRV_SERIAL_SOUNDCANVAS 0 /* Roland Soundcanvas; F5 NN selects part */
  54#define SNDRV_SERIAL_MS124T 1      /* Midiator MS-124T */
  55#define SNDRV_SERIAL_MS124W_SA 2   /* Midiator MS-124W in S/A mode */
  56#define SNDRV_SERIAL_MS124W_MB 3   /* Midiator MS-124W in M/B mode */
  57#define SNDRV_SERIAL_GENERIC 4     /* Generic Interface */
  58#define SNDRV_SERIAL_MAX_ADAPTOR SNDRV_SERIAL_GENERIC
  59static char *adaptor_names[] = {
  60	"Soundcanvas",
  61        "MS-124T",
  62	"MS-124W S/A",
  63	"MS-124W M/B",
  64	"Generic"
  65};
  66
  67#define SNDRV_SERIAL_NORMALBUFF 0 /* Normal blocking buffer operation */
  68#define SNDRV_SERIAL_DROPBUFF   1 /* Non-blocking discard operation */
  69
  70static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;	/* Index 0-MAX */
  71static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
  72static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE; /* Enable this card */
  73static long port[SNDRV_CARDS] = SNDRV_DEFAULT_PORT; /* 0x3f8,0x2f8,0x3e8,0x2e8 */
  74static int irq[SNDRV_CARDS] = SNDRV_DEFAULT_IRQ; 	/* 3,4,5,7,9,10,11,14,15 */
  75static int speed[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 38400}; /* 9600,19200,38400,57600,115200 */
  76static int base[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 115200}; /* baud base */
  77static int outs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};	 /* 1 to 16 */
  78static int ins[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};	/* 1 to 16 */
  79static int adaptor[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = SNDRV_SERIAL_SOUNDCANVAS};
  80static bool droponfull[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS -1)] = SNDRV_SERIAL_NORMALBUFF };
  81
  82module_param_array(index, int, NULL, 0444);
  83MODULE_PARM_DESC(index, "Index value for Serial MIDI.");
  84module_param_array(id, charp, NULL, 0444);
  85MODULE_PARM_DESC(id, "ID string for Serial MIDI.");
  86module_param_array(enable, bool, NULL, 0444);
  87MODULE_PARM_DESC(enable, "Enable UART16550A chip.");
  88module_param_array(port, long, NULL, 0444);
  89MODULE_PARM_DESC(port, "Port # for UART16550A chip.");
  90module_param_array(irq, int, NULL, 0444);
  91MODULE_PARM_DESC(irq, "IRQ # for UART16550A chip.");
  92module_param_array(speed, int, NULL, 0444);
  93MODULE_PARM_DESC(speed, "Speed in bauds.");
  94module_param_array(base, int, NULL, 0444);
  95MODULE_PARM_DESC(base, "Base for divisor in bauds.");
  96module_param_array(outs, int, NULL, 0444);
  97MODULE_PARM_DESC(outs, "Number of MIDI outputs.");
  98module_param_array(ins, int, NULL, 0444);
  99MODULE_PARM_DESC(ins, "Number of MIDI inputs.");
 100module_param_array(droponfull, bool, NULL, 0444);
 101MODULE_PARM_DESC(droponfull, "Flag to enable drop-on-full buffer mode");
 102
 103module_param_array(adaptor, int, NULL, 0444);
 104MODULE_PARM_DESC(adaptor, "Type of adaptor.");
 105
 106/*#define SNDRV_SERIAL_MS124W_MB_NOCOMBO 1*/  /* Address outs as 0-3 instead of bitmap */
 107
 108#define SNDRV_SERIAL_MAX_OUTS	16		/* max 64, min 16 */
 109#define SNDRV_SERIAL_MAX_INS	16		/* max 64, min 16 */
 110
 111#define TX_BUFF_SIZE		(1<<15)		/* Must be 2^n */
 112#define TX_BUFF_MASK		(TX_BUFF_SIZE - 1)
 113
 114#define SERIAL_MODE_NOT_OPENED 		(0)
 115#define SERIAL_MODE_INPUT_OPEN		(1 << 0)
 116#define SERIAL_MODE_OUTPUT_OPEN		(1 << 1)
 117#define SERIAL_MODE_INPUT_TRIGGERED	(1 << 2)
 118#define SERIAL_MODE_OUTPUT_TRIGGERED	(1 << 3)
 119
 120struct snd_uart16550 {
 121	struct snd_card *card;
 122	struct snd_rawmidi *rmidi;
 123	struct snd_rawmidi_substream *midi_output[SNDRV_SERIAL_MAX_OUTS];
 124	struct snd_rawmidi_substream *midi_input[SNDRV_SERIAL_MAX_INS];
 125
 126	int filemode;		/* open status of file */
 127
 128	spinlock_t open_lock;
 129
 130	int irq;
 131
 132	unsigned long base;
 133	struct resource *res_base;
 134
 135	unsigned int speed;
 136	unsigned int speed_base;
 137	unsigned char divisor;
 138
 139	unsigned char old_divisor_lsb;
 140	unsigned char old_divisor_msb;
 141	unsigned char old_line_ctrl_reg;
 142
 143	/* parameter for using of write loop */
 144	short int fifo_limit;	/* used in uart16550 */
 145        short int fifo_count;	/* used in uart16550 */
 146
 147	/* type of adaptor */
 148	int adaptor;
 149
 150	/* inputs */
 151	int prev_in;
 152	unsigned char rstatus;
 153
 154	/* outputs */
 155	int prev_out;
 156	unsigned char prev_status[SNDRV_SERIAL_MAX_OUTS];
 157
 158	/* write buffer and its writing/reading position */
 159	unsigned char tx_buff[TX_BUFF_SIZE];
 160	int buff_in_count;
 161        int buff_in;
 162        int buff_out;
 163        int drop_on_full;
 164
 165	/* wait timer */
 166	unsigned int timer_running:1;
 167	struct timer_list buffer_timer;
 168
 169};
 170
 171static struct platform_device *devices[SNDRV_CARDS];
 172
 173static inline void snd_uart16550_add_timer(struct snd_uart16550 *uart)
 174{
 175	if (!uart->timer_running) {
 176		/* timer 38600bps * 10bit * 16byte */
 177		uart->buffer_timer.expires = jiffies + (HZ+255)/256;
 178		uart->timer_running = 1;
 179		add_timer(&uart->buffer_timer);
 180	}
 181}
 182
 183static inline void snd_uart16550_del_timer(struct snd_uart16550 *uart)
 184{
 185	if (uart->timer_running) {
 186		del_timer(&uart->buffer_timer);
 187		uart->timer_running = 0;
 188	}
 189}
 190
 191/* This macro is only used in snd_uart16550_io_loop */
 192static inline void snd_uart16550_buffer_output(struct snd_uart16550 *uart)
 193{
 194	unsigned short buff_out = uart->buff_out;
 195	if (uart->buff_in_count > 0) {
 196		outb(uart->tx_buff[buff_out], uart->base + UART_TX);
 197		uart->fifo_count++;
 198		buff_out++;
 199		buff_out &= TX_BUFF_MASK;
 200		uart->buff_out = buff_out;
 201		uart->buff_in_count--;
 202	}
 203}
 204
 205/* This loop should be called with interrupts disabled
 206 * We don't want to interrupt this, 
 207 * as we're already handling an interrupt 
 208 */
 209static void snd_uart16550_io_loop(struct snd_uart16550 * uart)
 210{
 211	unsigned char c, status;
 212	int substream;
 213
 214	/* recall previous stream */
 215	substream = uart->prev_in;
 216
 217	/* Read Loop */
 218	while ((status = inb(uart->base + UART_LSR)) & UART_LSR_DR) {
 219		/* while receive data ready */
 220		c = inb(uart->base + UART_RX);
 221
 222		/* keep track of last status byte */
 223		if (c & 0x80)
 224			uart->rstatus = c;
 225
 226		/* handle stream switch */
 227		if (uart->adaptor == SNDRV_SERIAL_GENERIC) {
 228			if (uart->rstatus == 0xf5) {
 229				if (c <= SNDRV_SERIAL_MAX_INS && c > 0)
 230					substream = c - 1;
 231				if (c != 0xf5)
 232					/* prevent future bytes from being
 233					   interpreted as streams */
 234					uart->rstatus = 0;
 235			} else if ((uart->filemode & SERIAL_MODE_INPUT_OPEN)
 236				   && uart->midi_input[substream])
 237				snd_rawmidi_receive(uart->midi_input[substream],
 238						    &c, 1);
 239		} else if ((uart->filemode & SERIAL_MODE_INPUT_OPEN) &&
 240			   uart->midi_input[substream])
 241			snd_rawmidi_receive(uart->midi_input[substream], &c, 1);
 242
 243		if (status & UART_LSR_OE)
 244			snd_printk(KERN_WARNING
 245				   "%s: Overrun on device at 0x%lx\n",
 246			       uart->rmidi->name, uart->base);
 247	}
 248
 249	/* remember the last stream */
 250	uart->prev_in = substream;
 251
 252	/* no need of check SERIAL_MODE_OUTPUT_OPEN because if not,
 253	   buffer is never filled. */
 254	/* Check write status */
 255	if (status & UART_LSR_THRE)
 256		uart->fifo_count = 0;
 257	if (uart->adaptor == SNDRV_SERIAL_MS124W_SA
 258	   || uart->adaptor == SNDRV_SERIAL_GENERIC) {
 259		/* Can't use FIFO, must send only when CTS is true */
 260		status = inb(uart->base + UART_MSR);
 261		while (uart->fifo_count == 0 && (status & UART_MSR_CTS) &&
 262		       uart->buff_in_count > 0) {
 263		       snd_uart16550_buffer_output(uart);
 264		       status = inb(uart->base + UART_MSR);
 265		}
 266	} else {
 267		/* Write loop */
 268		while (uart->fifo_count < uart->fifo_limit /* Can we write ? */
 269		       && uart->buff_in_count > 0)	/* Do we want to? */
 270			snd_uart16550_buffer_output(uart);
 271	}
 272	if (uart->irq < 0 && uart->buff_in_count > 0)
 273		snd_uart16550_add_timer(uart);
 274}
 275
 276/* NOTES ON SERVICING INTERUPTS
 277 * ---------------------------
 278 * After receiving a interrupt, it is important to indicate to the UART that
 279 * this has been done. 
 280 * For a Rx interrupt, this is done by reading the received byte.
 281 * For a Tx interrupt this is done by either:
 282 * a) Writing a byte
 283 * b) Reading the IIR
 284 * It is particularly important to read the IIR if a Tx interrupt is received
 285 * when there is no data in tx_buff[], as in this case there no other
 286 * indication that the interrupt has been serviced, and it remains outstanding
 287 * indefinitely. This has the curious side effect that and no further interrupts
 288 * will be generated from this device AT ALL!!.
 289 * It is also desirable to clear outstanding interrupts when the device is
 290 * opened/closed.
 291 *
 292 *
 293 * Note that some devices need OUT2 to be set before they will generate
 294 * interrupts at all. (Possibly tied to an internal pull-up on CTS?)
 295 */
 296static irqreturn_t snd_uart16550_interrupt(int irq, void *dev_id)
 297{
 298	struct snd_uart16550 *uart;
 299
 300	uart = dev_id;
 301	spin_lock(&uart->open_lock);
 302	if (uart->filemode == SERIAL_MODE_NOT_OPENED) {
 303		spin_unlock(&uart->open_lock);
 304		return IRQ_NONE;
 305	}
 306	/* indicate to the UART that the interrupt has been serviced */
 307	inb(uart->base + UART_IIR);
 308	snd_uart16550_io_loop(uart);
 309	spin_unlock(&uart->open_lock);
 310	return IRQ_HANDLED;
 311}
 312
 313/* When the polling mode, this function calls snd_uart16550_io_loop. */
 314static void snd_uart16550_buffer_timer(unsigned long data)
 315{
 316	unsigned long flags;
 317	struct snd_uart16550 *uart;
 318
 319	uart = (struct snd_uart16550 *)data;
 320	spin_lock_irqsave(&uart->open_lock, flags);
 321	snd_uart16550_del_timer(uart);
 322	snd_uart16550_io_loop(uart);
 323	spin_unlock_irqrestore(&uart->open_lock, flags);
 324}
 325
 326/*
 327 *  this method probes, if an uart sits on given port
 328 *  return 0 if found
 329 *  return negative error if not found
 330 */
 331static int snd_uart16550_detect(struct snd_uart16550 *uart)
 332{
 333	unsigned long io_base = uart->base;
 334	int ok;
 335	unsigned char c;
 336
 337	/* Do some vague tests for the presence of the uart */
 338	if (io_base == 0 || io_base == SNDRV_AUTO_PORT) {
 339		return -ENODEV;	/* Not configured */
 340	}
 341
 342	uart->res_base = request_region(io_base, 8, "Serial MIDI");
 343	if (uart->res_base == NULL) {
 344		snd_printk(KERN_ERR "u16550: can't grab port 0x%lx\n", io_base);
 345		return -EBUSY;
 346	}
 347
 348	/* uart detected unless one of the following tests should fail */
 349	ok = 1;
 350	/* 8 data-bits, 1 stop-bit, parity off, DLAB = 0 */
 351	outb(UART_LCR_WLEN8, io_base + UART_LCR); /* Line Control Register */
 352	c = inb(io_base + UART_IER);
 353	/* The top four bits of the IER should always == 0 */
 354	if ((c & 0xf0) != 0)
 355		ok = 0;		/* failed */
 356
 357	outb(0xaa, io_base + UART_SCR);
 358	/* Write arbitrary data into the scratch reg */
 359	c = inb(io_base + UART_SCR);
 360	/* If it comes back, it's OK */
 361	if (c != 0xaa)
 362		ok = 0;		/* failed */
 363
 364	outb(0x55, io_base + UART_SCR);
 365	/* Write arbitrary data into the scratch reg */
 366	c = inb(io_base + UART_SCR);
 367	/* If it comes back, it's OK */
 368	if (c != 0x55)
 369		ok = 0;		/* failed */
 370
 371	return ok;
 372}
 373
 374static void snd_uart16550_do_open(struct snd_uart16550 * uart)
 375{
 376	char byte;
 377
 378	/* Initialize basic variables */
 379	uart->buff_in_count = 0;
 380	uart->buff_in = 0;
 381	uart->buff_out = 0;
 382	uart->fifo_limit = 1;
 383	uart->fifo_count = 0;
 384	uart->timer_running = 0;
 385
 386	outb(UART_FCR_ENABLE_FIFO	/* Enable FIFO's (if available) */
 387	     | UART_FCR_CLEAR_RCVR	/* Clear receiver FIFO */
 388	     | UART_FCR_CLEAR_XMIT	/* Clear transmitter FIFO */
 389	     | UART_FCR_TRIGGER_4	/* Set FIFO trigger at 4-bytes */
 390	/* NOTE: interrupt generated after T=(time)4-bytes
 391	 * if less than UART_FCR_TRIGGER bytes received
 392	 */
 393	     ,uart->base + UART_FCR);	/* FIFO Control Register */
 394
 395	if ((inb(uart->base + UART_IIR) & 0xf0) == 0xc0)
 396		uart->fifo_limit = 16;
 397	if (uart->divisor != 0) {
 398		uart->old_line_ctrl_reg = inb(uart->base + UART_LCR);
 399		outb(UART_LCR_DLAB	/* Divisor latch access bit */
 400		     ,uart->base + UART_LCR);	/* Line Control Register */
 401		uart->old_divisor_lsb = inb(uart->base + UART_DLL);
 402		uart->old_divisor_msb = inb(uart->base + UART_DLM);
 403
 404		outb(uart->divisor
 405		     ,uart->base + UART_DLL);	/* Divisor Latch Low */
 406		outb(0
 407		     ,uart->base + UART_DLM);	/* Divisor Latch High */
 408		/* DLAB is reset to 0 in next outb() */
 409	}
 410	/* Set serial parameters (parity off, etc) */
 411	outb(UART_LCR_WLEN8	/* 8 data-bits */
 412	     | 0		/* 1 stop-bit */
 413	     | 0		/* parity off */
 414	     | 0		/* DLAB = 0 */
 415	     ,uart->base + UART_LCR);	/* Line Control Register */
 416
 417	switch (uart->adaptor) {
 418	default:
 419		outb(UART_MCR_RTS	/* Set Request-To-Send line active */
 420		     | UART_MCR_DTR	/* Set Data-Terminal-Ready line active */
 421		     | UART_MCR_OUT2	/* Set OUT2 - not always required, but when
 422					 * it is, it is ESSENTIAL for enabling interrupts
 423				 */
 424		     ,uart->base + UART_MCR);	/* Modem Control Register */
 425		break;
 426	case SNDRV_SERIAL_MS124W_SA:
 427	case SNDRV_SERIAL_MS124W_MB:
 428		/* MS-124W can draw power from RTS and DTR if they
 429		   are in opposite states. */ 
 430		outb(UART_MCR_RTS | (0&UART_MCR_DTR) | UART_MCR_OUT2,
 431		     uart->base + UART_MCR);
 432		break;
 433	case SNDRV_SERIAL_MS124T:
 434		/* MS-124T can draw power from RTS and/or DTR (preferably
 435		   both) if they are both asserted. */
 436		outb(UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2,
 437		     uart->base + UART_MCR);
 438		break;
 439	}
 440
 441	if (uart->irq < 0) {
 442		byte = (0 & UART_IER_RDI)	/* Disable Receiver data interrupt */
 443		    |(0 & UART_IER_THRI)	/* Disable Transmitter holding register empty interrupt */
 444		    ;
 445	} else if (uart->adaptor == SNDRV_SERIAL_MS124W_SA) {
 446		byte = UART_IER_RDI	/* Enable Receiver data interrupt */
 447		    | UART_IER_MSI	/* Enable Modem status interrupt */
 448		    ;
 449	} else if (uart->adaptor == SNDRV_SERIAL_GENERIC) {
 450		byte = UART_IER_RDI	/* Enable Receiver data interrupt */
 451		    | UART_IER_MSI	/* Enable Modem status interrupt */
 452		    | UART_IER_THRI	/* Enable Transmitter holding register empty interrupt */
 453		    ;
 454	} else {
 455		byte = UART_IER_RDI	/* Enable Receiver data interrupt */
 456		    | UART_IER_THRI	/* Enable Transmitter holding register empty interrupt */
 457		    ;
 458	}
 459	outb(byte, uart->base + UART_IER);	/* Interrupt enable Register */
 460
 461	inb(uart->base + UART_LSR);	/* Clear any pre-existing overrun indication */
 462	inb(uart->base + UART_IIR);	/* Clear any pre-existing transmit interrupt */
 463	inb(uart->base + UART_RX);	/* Clear any pre-existing receive interrupt */
 464}
 465
 466static void snd_uart16550_do_close(struct snd_uart16550 * uart)
 467{
 468	if (uart->irq < 0)
 469		snd_uart16550_del_timer(uart);
 470
 471	/* NOTE: may need to disable interrupts before de-registering out handler.
 472	 * For now, the consequences are harmless.
 473	 */
 474
 475	outb((0 & UART_IER_RDI)		/* Disable Receiver data interrupt */
 476	     |(0 & UART_IER_THRI)	/* Disable Transmitter holding register empty interrupt */
 477	     ,uart->base + UART_IER);	/* Interrupt enable Register */
 478
 479	switch (uart->adaptor) {
 480	default:
 481		outb((0 & UART_MCR_RTS)		/* Deactivate Request-To-Send line  */
 482		     |(0 & UART_MCR_DTR)	/* Deactivate Data-Terminal-Ready line */
 483		     |(0 & UART_MCR_OUT2)	/* Deactivate OUT2 */
 484		     ,uart->base + UART_MCR);	/* Modem Control Register */
 485	  break;
 486	case SNDRV_SERIAL_MS124W_SA:
 487	case SNDRV_SERIAL_MS124W_MB:
 488		/* MS-124W can draw power from RTS and DTR if they
 489		   are in opposite states; leave it powered. */ 
 490		outb(UART_MCR_RTS | (0&UART_MCR_DTR) | (0&UART_MCR_OUT2),
 491		     uart->base + UART_MCR);
 492		break;
 493	case SNDRV_SERIAL_MS124T:
 494		/* MS-124T can draw power from RTS and/or DTR (preferably
 495		   both) if they are both asserted; leave it powered. */
 496		outb(UART_MCR_RTS | UART_MCR_DTR | (0&UART_MCR_OUT2),
 497		     uart->base + UART_MCR);
 498		break;
 499	}
 500
 501	inb(uart->base + UART_IIR);	/* Clear any outstanding interrupts */
 502
 503	/* Restore old divisor */
 504	if (uart->divisor != 0) {
 505		outb(UART_LCR_DLAB		/* Divisor latch access bit */
 506		     ,uart->base + UART_LCR);	/* Line Control Register */
 507		outb(uart->old_divisor_lsb
 508		     ,uart->base + UART_DLL);	/* Divisor Latch Low */
 509		outb(uart->old_divisor_msb
 510		     ,uart->base + UART_DLM);	/* Divisor Latch High */
 511		/* Restore old LCR (data bits, stop bits, parity, DLAB) */
 512		outb(uart->old_line_ctrl_reg
 513		     ,uart->base + UART_LCR);	/* Line Control Register */
 514	}
 515}
 516
 517static int snd_uart16550_input_open(struct snd_rawmidi_substream *substream)
 518{
 519	unsigned long flags;
 520	struct snd_uart16550 *uart = substream->rmidi->private_data;
 521
 522	spin_lock_irqsave(&uart->open_lock, flags);
 523	if (uart->filemode == SERIAL_MODE_NOT_OPENED)
 524		snd_uart16550_do_open(uart);
 525	uart->filemode |= SERIAL_MODE_INPUT_OPEN;
 526	uart->midi_input[substream->number] = substream;
 527	spin_unlock_irqrestore(&uart->open_lock, flags);
 528	return 0;
 529}
 530
 531static int snd_uart16550_input_close(struct snd_rawmidi_substream *substream)
 532{
 533	unsigned long flags;
 534	struct snd_uart16550 *uart = substream->rmidi->private_data;
 535
 536	spin_lock_irqsave(&uart->open_lock, flags);
 537	uart->filemode &= ~SERIAL_MODE_INPUT_OPEN;
 538	uart->midi_input[substream->number] = NULL;
 539	if (uart->filemode == SERIAL_MODE_NOT_OPENED)
 540		snd_uart16550_do_close(uart);
 541	spin_unlock_irqrestore(&uart->open_lock, flags);
 542	return 0;
 543}
 544
 545static void snd_uart16550_input_trigger(struct snd_rawmidi_substream *substream,
 546					int up)
 547{
 548	unsigned long flags;
 549	struct snd_uart16550 *uart = substream->rmidi->private_data;
 550
 551	spin_lock_irqsave(&uart->open_lock, flags);
 552	if (up)
 553		uart->filemode |= SERIAL_MODE_INPUT_TRIGGERED;
 554	else
 555		uart->filemode &= ~SERIAL_MODE_INPUT_TRIGGERED;
 556	spin_unlock_irqrestore(&uart->open_lock, flags);
 557}
 558
 559static int snd_uart16550_output_open(struct snd_rawmidi_substream *substream)
 560{
 561	unsigned long flags;
 562	struct snd_uart16550 *uart = substream->rmidi->private_data;
 563
 564	spin_lock_irqsave(&uart->open_lock, flags);
 565	if (uart->filemode == SERIAL_MODE_NOT_OPENED)
 566		snd_uart16550_do_open(uart);
 567	uart->filemode |= SERIAL_MODE_OUTPUT_OPEN;
 568	uart->midi_output[substream->number] = substream;
 569	spin_unlock_irqrestore(&uart->open_lock, flags);
 570	return 0;
 571};
 572
 573static int snd_uart16550_output_close(struct snd_rawmidi_substream *substream)
 574{
 575	unsigned long flags;
 576	struct snd_uart16550 *uart = substream->rmidi->private_data;
 577
 578	spin_lock_irqsave(&uart->open_lock, flags);
 579	uart->filemode &= ~SERIAL_MODE_OUTPUT_OPEN;
 580	uart->midi_output[substream->number] = NULL;
 581	if (uart->filemode == SERIAL_MODE_NOT_OPENED)
 582		snd_uart16550_do_close(uart);
 583	spin_unlock_irqrestore(&uart->open_lock, flags);
 584	return 0;
 585};
 586
 587static inline int snd_uart16550_buffer_can_write(struct snd_uart16550 *uart,
 588						 int Num)
 589{
 590	if (uart->buff_in_count + Num < TX_BUFF_SIZE)
 591		return 1;
 592	else
 593		return 0;
 594}
 595
 596static inline int snd_uart16550_write_buffer(struct snd_uart16550 *uart,
 597					     unsigned char byte)
 598{
 599	unsigned short buff_in = uart->buff_in;
 600	if (uart->buff_in_count < TX_BUFF_SIZE) {
 601		uart->tx_buff[buff_in] = byte;
 602		buff_in++;
 603		buff_in &= TX_BUFF_MASK;
 604		uart->buff_in = buff_in;
 605		uart->buff_in_count++;
 606		if (uart->irq < 0) /* polling mode */
 607			snd_uart16550_add_timer(uart);
 608		return 1;
 609	} else
 610		return 0;
 611}
 612
 613static int snd_uart16550_output_byte(struct snd_uart16550 *uart,
 614				     struct snd_rawmidi_substream *substream,
 615				     unsigned char midi_byte)
 616{
 617	if (uart->buff_in_count == 0                    /* Buffer empty? */
 618	    && ((uart->adaptor != SNDRV_SERIAL_MS124W_SA &&
 619	    uart->adaptor != SNDRV_SERIAL_GENERIC) ||
 620		(uart->fifo_count == 0                  /* FIFO empty? */
 621		 && (inb(uart->base + UART_MSR) & UART_MSR_CTS)))) { /* CTS? */
 622
 623	        /* Tx Buffer Empty - try to write immediately */
 624		if ((inb(uart->base + UART_LSR) & UART_LSR_THRE) != 0) {
 625		        /* Transmitter holding register (and Tx FIFO) empty */
 626		        uart->fifo_count = 1;
 627			outb(midi_byte, uart->base + UART_TX);
 628		} else {
 629		        if (uart->fifo_count < uart->fifo_limit) {
 630			        uart->fifo_count++;
 631				outb(midi_byte, uart->base + UART_TX);
 632			} else {
 633			        /* Cannot write (buffer empty) -
 634				 * put char in buffer */
 635				snd_uart16550_write_buffer(uart, midi_byte);
 636			}
 637		}
 638	} else {
 639		if (!snd_uart16550_write_buffer(uart, midi_byte)) {
 640			snd_printk(KERN_WARNING
 641				   "%s: Buffer overrun on device at 0x%lx\n",
 642				   uart->rmidi->name, uart->base);
 643			return 0;
 644		}
 645	}
 646
 647	return 1;
 648}
 649
 650static void snd_uart16550_output_write(struct snd_rawmidi_substream *substream)
 651{
 652	unsigned long flags;
 653	unsigned char midi_byte, addr_byte;
 654	struct snd_uart16550 *uart = substream->rmidi->private_data;
 655	char first;
 656	static unsigned long lasttime = 0;
 657	
 658	/* Interrupts are disabled during the updating of the tx_buff,
 659	 * since it is 'bad' to have two processes updating the same
 660	 * variables (ie buff_in & buff_out)
 661	 */
 662
 663	spin_lock_irqsave(&uart->open_lock, flags);
 664
 665	if (uart->irq < 0)	/* polling */
 666		snd_uart16550_io_loop(uart);
 667
 668	if (uart->adaptor == SNDRV_SERIAL_MS124W_MB) {
 669		while (1) {
 670			/* buffer full? */
 671			/* in this mode we need two bytes of space */
 672			if (uart->buff_in_count > TX_BUFF_SIZE - 2)
 673				break;
 674			if (snd_rawmidi_transmit(substream, &midi_byte, 1) != 1)
 675				break;
 676#ifdef SNDRV_SERIAL_MS124W_MB_NOCOMBO
 677			/* select exactly one of the four ports */
 678			addr_byte = (1 << (substream->number + 4)) | 0x08;
 679#else
 680			/* select any combination of the four ports */
 681			addr_byte = (substream->number << 4) | 0x08;
 682			/* ...except none */
 683			if (addr_byte == 0x08)
 684				addr_byte = 0xf8;
 685#endif
 686			snd_uart16550_output_byte(uart, substream, addr_byte);
 687			/* send midi byte */
 688			snd_uart16550_output_byte(uart, substream, midi_byte);
 689		}
 690	} else {
 691		first = 0;
 692		while (snd_rawmidi_transmit_peek(substream, &midi_byte, 1) == 1) {
 693			/* Also send F5 after 3 seconds with no data
 694			 * to handle device disconnect */
 695			if (first == 0 &&
 696			    (uart->adaptor == SNDRV_SERIAL_SOUNDCANVAS ||
 697			     uart->adaptor == SNDRV_SERIAL_GENERIC) &&
 698			    (uart->prev_out != substream->number ||
 699			     time_after(jiffies, lasttime + 3*HZ))) {
 700
 701				if (snd_uart16550_buffer_can_write(uart, 3)) {
 702					/* Roland Soundcanvas part selection */
 703					/* If this substream of the data is
 704					 * different previous substream
 705					 * in this uart, send the change part
 706					 * event
 707					 */
 708					uart->prev_out = substream->number;
 709					/* change part */
 710					snd_uart16550_output_byte(uart, substream,
 711								  0xf5);
 712					/* data */
 713					snd_uart16550_output_byte(uart, substream,
 714								  uart->prev_out + 1);
 715					/* If midi_byte is a data byte,
 716					 * send the previous status byte */
 717					if (midi_byte < 0x80 &&
 718					    uart->adaptor == SNDRV_SERIAL_SOUNDCANVAS)
 719						snd_uart16550_output_byte(uart, substream, uart->prev_status[uart->prev_out]);
 720				} else if (!uart->drop_on_full)
 721					break;
 722
 723			}
 724
 725			/* send midi byte */
 726			if (!snd_uart16550_output_byte(uart, substream, midi_byte) &&
 727			    !uart->drop_on_full )
 728				break;
 729
 730			if (midi_byte >= 0x80 && midi_byte < 0xf0)
 731				uart->prev_status[uart->prev_out] = midi_byte;
 732			first = 1;
 733
 734			snd_rawmidi_transmit_ack( substream, 1 );
 735		}
 736		lasttime = jiffies;
 737	}
 738	spin_unlock_irqrestore(&uart->open_lock, flags);
 739}
 740
 741static void snd_uart16550_output_trigger(struct snd_rawmidi_substream *substream,
 742					 int up)
 743{
 744	unsigned long flags;
 745	struct snd_uart16550 *uart = substream->rmidi->private_data;
 746
 747	spin_lock_irqsave(&uart->open_lock, flags);
 748	if (up)
 749		uart->filemode |= SERIAL_MODE_OUTPUT_TRIGGERED;
 750	else
 751		uart->filemode &= ~SERIAL_MODE_OUTPUT_TRIGGERED;
 752	spin_unlock_irqrestore(&uart->open_lock, flags);
 753	if (up)
 754		snd_uart16550_output_write(substream);
 755}
 756
 757static struct snd_rawmidi_ops snd_uart16550_output =
 758{
 759	.open =		snd_uart16550_output_open,
 760	.close =	snd_uart16550_output_close,
 761	.trigger =	snd_uart16550_output_trigger,
 762};
 763
 764static struct snd_rawmidi_ops snd_uart16550_input =
 765{
 766	.open =		snd_uart16550_input_open,
 767	.close =	snd_uart16550_input_close,
 768	.trigger =	snd_uart16550_input_trigger,
 769};
 770
 771static int snd_uart16550_free(struct snd_uart16550 *uart)
 772{
 773	if (uart->irq >= 0)
 774		free_irq(uart->irq, uart);
 775	release_and_free_resource(uart->res_base);
 776	kfree(uart);
 777	return 0;
 778};
 779
 780static int snd_uart16550_dev_free(struct snd_device *device)
 781{
 782	struct snd_uart16550 *uart = device->device_data;
 783	return snd_uart16550_free(uart);
 784}
 785
 786static int snd_uart16550_create(struct snd_card *card,
 787				unsigned long iobase,
 788				int irq,
 789				unsigned int speed,
 790				unsigned int base,
 791				int adaptor,
 792				int droponfull,
 793				struct snd_uart16550 **ruart)
 794{
 795	static struct snd_device_ops ops = {
 796		.dev_free =	snd_uart16550_dev_free,
 797	};
 798	struct snd_uart16550 *uart;
 799	int err;
 800
 801
 802	if ((uart = kzalloc(sizeof(*uart), GFP_KERNEL)) == NULL)
 
 803		return -ENOMEM;
 804	uart->adaptor = adaptor;
 805	uart->card = card;
 806	spin_lock_init(&uart->open_lock);
 807	uart->irq = -1;
 808	uart->base = iobase;
 809	uart->drop_on_full = droponfull;
 810
 811	if ((err = snd_uart16550_detect(uart)) <= 0) {
 812		printk(KERN_ERR "no UART detected at 0x%lx\n", iobase);
 813		snd_uart16550_free(uart);
 814		return -ENODEV;
 815	}
 816
 817	if (irq >= 0 && irq != SNDRV_AUTO_IRQ) {
 818		if (request_irq(irq, snd_uart16550_interrupt,
 819				0, "Serial MIDI", uart)) {
 820			snd_printk(KERN_WARNING
 821				   "irq %d busy. Using Polling.\n", irq);
 822		} else {
 823			uart->irq = irq;
 824		}
 825	}
 826	uart->divisor = base / speed;
 827	uart->speed = base / (unsigned int)uart->divisor;
 828	uart->speed_base = base;
 829	uart->prev_out = -1;
 830	uart->prev_in = 0;
 831	uart->rstatus = 0;
 832	memset(uart->prev_status, 0x80, sizeof(unsigned char) * SNDRV_SERIAL_MAX_OUTS);
 833	init_timer(&uart->buffer_timer);
 834	uart->buffer_timer.function = snd_uart16550_buffer_timer;
 835	uart->buffer_timer.data = (unsigned long)uart;
 836	uart->timer_running = 0;
 837
 838	/* Register device */
 839	if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, uart, &ops)) < 0) {
 840		snd_uart16550_free(uart);
 841		return err;
 842	}
 843
 844	switch (uart->adaptor) {
 845	case SNDRV_SERIAL_MS124W_SA:
 846	case SNDRV_SERIAL_MS124W_MB:
 847		/* MS-124W can draw power from RTS and DTR if they
 848		   are in opposite states. */ 
 849		outb(UART_MCR_RTS | (0&UART_MCR_DTR), uart->base + UART_MCR);
 850		break;
 851	case SNDRV_SERIAL_MS124T:
 852		/* MS-124T can draw power from RTS and/or DTR (preferably
 853		   both) if they are asserted. */
 854		outb(UART_MCR_RTS | UART_MCR_DTR, uart->base + UART_MCR);
 855		break;
 856	default:
 857		break;
 858	}
 859
 860	if (ruart)
 861		*ruart = uart;
 862
 863	return 0;
 864}
 865
 866static void snd_uart16550_substreams(struct snd_rawmidi_str *stream)
 867{
 868	struct snd_rawmidi_substream *substream;
 869
 870	list_for_each_entry(substream, &stream->substreams, list) {
 871		sprintf(substream->name, "Serial MIDI %d", substream->number + 1);
 872	}
 873}
 874
 875static int snd_uart16550_rmidi(struct snd_uart16550 *uart, int device,
 876			       int outs, int ins,
 877			       struct snd_rawmidi **rmidi)
 878{
 879	struct snd_rawmidi *rrawmidi;
 880	int err;
 881
 882	err = snd_rawmidi_new(uart->card, "UART Serial MIDI", device,
 883			      outs, ins, &rrawmidi);
 884	if (err < 0)
 885		return err;
 886	snd_rawmidi_set_ops(rrawmidi, SNDRV_RAWMIDI_STREAM_INPUT,
 887			    &snd_uart16550_input);
 888	snd_rawmidi_set_ops(rrawmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
 889			    &snd_uart16550_output);
 890	strcpy(rrawmidi->name, "Serial MIDI");
 891	snd_uart16550_substreams(&rrawmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT]);
 892	snd_uart16550_substreams(&rrawmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT]);
 893	rrawmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
 894			       SNDRV_RAWMIDI_INFO_INPUT |
 895			       SNDRV_RAWMIDI_INFO_DUPLEX;
 896	rrawmidi->private_data = uart;
 897	if (rmidi)
 898		*rmidi = rrawmidi;
 899	return 0;
 900}
 901
 902static int snd_serial_probe(struct platform_device *devptr)
 903{
 904	struct snd_card *card;
 905	struct snd_uart16550 *uart;
 906	int err;
 907	int dev = devptr->id;
 908
 909	switch (adaptor[dev]) {
 910	case SNDRV_SERIAL_SOUNDCANVAS:
 911		ins[dev] = 1;
 912		break;
 913	case SNDRV_SERIAL_MS124T:
 914	case SNDRV_SERIAL_MS124W_SA:
 915		outs[dev] = 1;
 916		ins[dev] = 1;
 917		break;
 918	case SNDRV_SERIAL_MS124W_MB:
 919		outs[dev] = 16;
 920		ins[dev] = 1;
 921		break;
 922	case SNDRV_SERIAL_GENERIC:
 923		break;
 924	default:
 925		snd_printk(KERN_ERR
 926			   "Adaptor type is out of range 0-%d (%d)\n",
 927			   SNDRV_SERIAL_MAX_ADAPTOR, adaptor[dev]);
 928		return -ENODEV;
 929	}
 930
 931	if (outs[dev] < 1 || outs[dev] > SNDRV_SERIAL_MAX_OUTS) {
 932		snd_printk(KERN_ERR
 933			   "Count of outputs is out of range 1-%d (%d)\n",
 934			   SNDRV_SERIAL_MAX_OUTS, outs[dev]);
 935		return -ENODEV;
 936	}
 937
 938	if (ins[dev] < 1 || ins[dev] > SNDRV_SERIAL_MAX_INS) {
 939		snd_printk(KERN_ERR
 940			   "Count of inputs is out of range 1-%d (%d)\n",
 941			   SNDRV_SERIAL_MAX_INS, ins[dev]);
 942		return -ENODEV;
 943	}
 944
 945	err  = snd_card_new(&devptr->dev, index[dev], id[dev], THIS_MODULE,
 946			    0, &card);
 947	if (err < 0)
 948		return err;
 949
 950	strcpy(card->driver, "Serial");
 951	strcpy(card->shortname, "Serial MIDI (UART16550A)");
 952
 953	if ((err = snd_uart16550_create(card,
 954					port[dev],
 955					irq[dev],
 956					speed[dev],
 957					base[dev],
 958					adaptor[dev],
 959					droponfull[dev],
 960					&uart)) < 0)
 961		goto _err;
 962
 963	err = snd_uart16550_rmidi(uart, 0, outs[dev], ins[dev], &uart->rmidi);
 964	if (err < 0)
 965		goto _err;
 966
 967	sprintf(card->longname, "%s [%s] at %#lx, irq %d",
 968		card->shortname,
 969		adaptor_names[uart->adaptor],
 970		uart->base,
 971		uart->irq);
 972
 973	if ((err = snd_card_register(card)) < 0)
 974		goto _err;
 
 975
 976	platform_set_drvdata(devptr, card);
 977	return 0;
 978
 979 _err:
 980	snd_card_free(card);
 981	return err;
 982}
 983
 984static int snd_serial_remove(struct platform_device *devptr)
 985{
 986	snd_card_free(platform_get_drvdata(devptr));
 987	return 0;
 988}
 989
 990#define SND_SERIAL_DRIVER	"snd_serial_u16550"
 991
 992static struct platform_driver snd_serial_driver = {
 993	.probe		= snd_serial_probe,
 994	.remove		=  snd_serial_remove,
 995	.driver		= {
 996		.name	= SND_SERIAL_DRIVER,
 997		.owner	= THIS_MODULE,
 998	},
 999};
1000
1001static void snd_serial_unregister_all(void)
1002{
1003	int i;
1004
1005	for (i = 0; i < ARRAY_SIZE(devices); ++i)
1006		platform_device_unregister(devices[i]);
1007	platform_driver_unregister(&snd_serial_driver);
1008}
1009
1010static int __init alsa_card_serial_init(void)
1011{
1012	int i, cards, err;
1013
1014	if ((err = platform_driver_register(&snd_serial_driver)) < 0)
 
1015		return err;
1016
1017	cards = 0;
1018	for (i = 0; i < SNDRV_CARDS; i++) {
1019		struct platform_device *device;
1020		if (! enable[i])
1021			continue;
1022		device = platform_device_register_simple(SND_SERIAL_DRIVER,
1023							 i, NULL, 0);
1024		if (IS_ERR(device))
1025			continue;
1026		if (!platform_get_drvdata(device)) {
1027			platform_device_unregister(device);
1028			continue;
1029		}
1030		devices[i] = device;
1031		cards++;
1032	}
1033	if (! cards) {
1034#ifdef MODULE
1035		printk(KERN_ERR "serial midi soundcard not found or device busy\n");
1036#endif
1037		snd_serial_unregister_all();
1038		return -ENODEV;
1039	}
1040	return 0;
1041}
1042
1043static void __exit alsa_card_serial_exit(void)
1044{
1045	snd_serial_unregister_all();
1046}
1047
1048module_init(alsa_card_serial_init)
1049module_exit(alsa_card_serial_exit)
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *   serial.c
  4 *   Copyright (c) by Jaroslav Kysela <perex@perex.cz>,
  5 *                    Isaku Yamahata <yamahata@private.email.ne.jp>,
  6 *		      George Hansper <ghansper@apana.org.au>,
  7 *		      Hannu Savolainen
  8 *
  9 *   This code is based on the code from ALSA 0.5.9, but heavily rewritten.
 10 *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 11 * Sat Mar 31 17:27:57 PST 2001 tim.mann@compaq.com 
 12 *      Added support for the Midiator MS-124T and for the MS-124W in
 13 *      Single Addressed (S/A) or Multiple Burst (M/B) mode, with
 14 *      power derived either parasitically from the serial port or
 15 *      from a separate power supply.
 16 *
 17 *      More documentation can be found in serial-u16550.txt.
 18 */
 19
 20#include <linux/init.h>
 21#include <linux/interrupt.h>
 22#include <linux/err.h>
 23#include <linux/platform_device.h>
 24#include <linux/slab.h>
 25#include <linux/ioport.h>
 26#include <linux/module.h>
 27#include <linux/io.h>
 28#include <sound/core.h>
 29#include <sound/rawmidi.h>
 30#include <sound/initval.h>
 31
 32#include <linux/serial_reg.h>
 33#include <linux/jiffies.h>
 34
 
 
 35MODULE_DESCRIPTION("MIDI serial u16550");
 36MODULE_LICENSE("GPL");
 
 37
 38#define SNDRV_SERIAL_SOUNDCANVAS 0 /* Roland Soundcanvas; F5 NN selects part */
 39#define SNDRV_SERIAL_MS124T 1      /* Midiator MS-124T */
 40#define SNDRV_SERIAL_MS124W_SA 2   /* Midiator MS-124W in S/A mode */
 41#define SNDRV_SERIAL_MS124W_MB 3   /* Midiator MS-124W in M/B mode */
 42#define SNDRV_SERIAL_GENERIC 4     /* Generic Interface */
 43#define SNDRV_SERIAL_MAX_ADAPTOR SNDRV_SERIAL_GENERIC
 44static const char * const adaptor_names[] = {
 45	"Soundcanvas",
 46        "MS-124T",
 47	"MS-124W S/A",
 48	"MS-124W M/B",
 49	"Generic"
 50};
 51
 52#define SNDRV_SERIAL_NORMALBUFF 0 /* Normal blocking buffer operation */
 53#define SNDRV_SERIAL_DROPBUFF   1 /* Non-blocking discard operation */
 54
 55static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;	/* Index 0-MAX */
 56static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
 57static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE; /* Enable this card */
 58static long port[SNDRV_CARDS] = SNDRV_DEFAULT_PORT; /* 0x3f8,0x2f8,0x3e8,0x2e8 */
 59static int irq[SNDRV_CARDS] = SNDRV_DEFAULT_IRQ; 	/* 3,4,5,7,9,10,11,14,15 */
 60static int speed[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 38400}; /* 9600,19200,38400,57600,115200 */
 61static int base[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 115200}; /* baud base */
 62static int outs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};	 /* 1 to 16 */
 63static int ins[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};	/* 1 to 16 */
 64static int adaptor[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = SNDRV_SERIAL_SOUNDCANVAS};
 65static bool droponfull[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS -1)] = SNDRV_SERIAL_NORMALBUFF };
 66
 67module_param_array(index, int, NULL, 0444);
 68MODULE_PARM_DESC(index, "Index value for Serial MIDI.");
 69module_param_array(id, charp, NULL, 0444);
 70MODULE_PARM_DESC(id, "ID string for Serial MIDI.");
 71module_param_array(enable, bool, NULL, 0444);
 72MODULE_PARM_DESC(enable, "Enable UART16550A chip.");
 73module_param_hw_array(port, long, ioport, NULL, 0444);
 74MODULE_PARM_DESC(port, "Port # for UART16550A chip.");
 75module_param_hw_array(irq, int, irq, NULL, 0444);
 76MODULE_PARM_DESC(irq, "IRQ # for UART16550A chip.");
 77module_param_array(speed, int, NULL, 0444);
 78MODULE_PARM_DESC(speed, "Speed in bauds.");
 79module_param_array(base, int, NULL, 0444);
 80MODULE_PARM_DESC(base, "Base for divisor in bauds.");
 81module_param_array(outs, int, NULL, 0444);
 82MODULE_PARM_DESC(outs, "Number of MIDI outputs.");
 83module_param_array(ins, int, NULL, 0444);
 84MODULE_PARM_DESC(ins, "Number of MIDI inputs.");
 85module_param_array(droponfull, bool, NULL, 0444);
 86MODULE_PARM_DESC(droponfull, "Flag to enable drop-on-full buffer mode");
 87
 88module_param_array(adaptor, int, NULL, 0444);
 89MODULE_PARM_DESC(adaptor, "Type of adaptor.");
 90
 91/*#define SNDRV_SERIAL_MS124W_MB_NOCOMBO 1*/  /* Address outs as 0-3 instead of bitmap */
 92
 93#define SNDRV_SERIAL_MAX_OUTS	16		/* max 64, min 16 */
 94#define SNDRV_SERIAL_MAX_INS	16		/* max 64, min 16 */
 95
 96#define TX_BUFF_SIZE		(1<<15)		/* Must be 2^n */
 97#define TX_BUFF_MASK		(TX_BUFF_SIZE - 1)
 98
 99#define SERIAL_MODE_NOT_OPENED 		(0)
100#define SERIAL_MODE_INPUT_OPEN		(1 << 0)
101#define SERIAL_MODE_OUTPUT_OPEN		(1 << 1)
102#define SERIAL_MODE_INPUT_TRIGGERED	(1 << 2)
103#define SERIAL_MODE_OUTPUT_TRIGGERED	(1 << 3)
104
105struct snd_uart16550 {
106	struct snd_card *card;
107	struct snd_rawmidi *rmidi;
108	struct snd_rawmidi_substream *midi_output[SNDRV_SERIAL_MAX_OUTS];
109	struct snd_rawmidi_substream *midi_input[SNDRV_SERIAL_MAX_INS];
110
111	int filemode;		/* open status of file */
112
113	spinlock_t open_lock;
114
115	int irq;
116
117	unsigned long base;
 
118
119	unsigned int speed;
120	unsigned int speed_base;
121	unsigned char divisor;
122
123	unsigned char old_divisor_lsb;
124	unsigned char old_divisor_msb;
125	unsigned char old_line_ctrl_reg;
126
127	/* parameter for using of write loop */
128	short int fifo_limit;	/* used in uart16550 */
129        short int fifo_count;	/* used in uart16550 */
130
131	/* type of adaptor */
132	int adaptor;
133
134	/* inputs */
135	int prev_in;
136	unsigned char rstatus;
137
138	/* outputs */
139	int prev_out;
140	unsigned char prev_status[SNDRV_SERIAL_MAX_OUTS];
141
142	/* write buffer and its writing/reading position */
143	unsigned char tx_buff[TX_BUFF_SIZE];
144	int buff_in_count;
145        int buff_in;
146        int buff_out;
147        int drop_on_full;
148
149	/* wait timer */
150	unsigned int timer_running:1;
151	struct timer_list buffer_timer;
152
153};
154
155static struct platform_device *devices[SNDRV_CARDS];
156
157static inline void snd_uart16550_add_timer(struct snd_uart16550 *uart)
158{
159	if (!uart->timer_running) {
160		/* timer 38600bps * 10bit * 16byte */
161		mod_timer(&uart->buffer_timer, jiffies + (HZ + 255) / 256);
162		uart->timer_running = 1;
 
163	}
164}
165
166static inline void snd_uart16550_del_timer(struct snd_uart16550 *uart)
167{
168	if (uart->timer_running) {
169		del_timer(&uart->buffer_timer);
170		uart->timer_running = 0;
171	}
172}
173
174/* This macro is only used in snd_uart16550_io_loop */
175static inline void snd_uart16550_buffer_output(struct snd_uart16550 *uart)
176{
177	unsigned short buff_out = uart->buff_out;
178	if (uart->buff_in_count > 0) {
179		outb(uart->tx_buff[buff_out], uart->base + UART_TX);
180		uart->fifo_count++;
181		buff_out++;
182		buff_out &= TX_BUFF_MASK;
183		uart->buff_out = buff_out;
184		uart->buff_in_count--;
185	}
186}
187
188/* This loop should be called with interrupts disabled
189 * We don't want to interrupt this, 
190 * as we're already handling an interrupt 
191 */
192static void snd_uart16550_io_loop(struct snd_uart16550 * uart)
193{
194	unsigned char c, status;
195	int substream;
196
197	/* recall previous stream */
198	substream = uart->prev_in;
199
200	/* Read Loop */
201	while ((status = inb(uart->base + UART_LSR)) & UART_LSR_DR) {
202		/* while receive data ready */
203		c = inb(uart->base + UART_RX);
204
205		/* keep track of last status byte */
206		if (c & 0x80)
207			uart->rstatus = c;
208
209		/* handle stream switch */
210		if (uart->adaptor == SNDRV_SERIAL_GENERIC) {
211			if (uart->rstatus == 0xf5) {
212				if (c <= SNDRV_SERIAL_MAX_INS && c > 0)
213					substream = c - 1;
214				if (c != 0xf5)
215					/* prevent future bytes from being
216					   interpreted as streams */
217					uart->rstatus = 0;
218			} else if ((uart->filemode & SERIAL_MODE_INPUT_OPEN)
219				   && uart->midi_input[substream])
220				snd_rawmidi_receive(uart->midi_input[substream],
221						    &c, 1);
222		} else if ((uart->filemode & SERIAL_MODE_INPUT_OPEN) &&
223			   uart->midi_input[substream])
224			snd_rawmidi_receive(uart->midi_input[substream], &c, 1);
225
226		if (status & UART_LSR_OE)
227			dev_warn(uart->card->dev,
228				 "%s: Overrun on device at 0x%lx\n",
229				 uart->rmidi->name, uart->base);
230	}
231
232	/* remember the last stream */
233	uart->prev_in = substream;
234
235	/* no need of check SERIAL_MODE_OUTPUT_OPEN because if not,
236	   buffer is never filled. */
237	/* Check write status */
238	if (status & UART_LSR_THRE)
239		uart->fifo_count = 0;
240	if (uart->adaptor == SNDRV_SERIAL_MS124W_SA
241	   || uart->adaptor == SNDRV_SERIAL_GENERIC) {
242		/* Can't use FIFO, must send only when CTS is true */
243		status = inb(uart->base + UART_MSR);
244		while (uart->fifo_count == 0 && (status & UART_MSR_CTS) &&
245		       uart->buff_in_count > 0) {
246		       snd_uart16550_buffer_output(uart);
247		       status = inb(uart->base + UART_MSR);
248		}
249	} else {
250		/* Write loop */
251		while (uart->fifo_count < uart->fifo_limit /* Can we write ? */
252		       && uart->buff_in_count > 0)	/* Do we want to? */
253			snd_uart16550_buffer_output(uart);
254	}
255	if (uart->irq < 0 && uart->buff_in_count > 0)
256		snd_uart16550_add_timer(uart);
257}
258
259/* NOTES ON SERVICING INTERUPTS
260 * ---------------------------
261 * After receiving a interrupt, it is important to indicate to the UART that
262 * this has been done. 
263 * For a Rx interrupt, this is done by reading the received byte.
264 * For a Tx interrupt this is done by either:
265 * a) Writing a byte
266 * b) Reading the IIR
267 * It is particularly important to read the IIR if a Tx interrupt is received
268 * when there is no data in tx_buff[], as in this case there no other
269 * indication that the interrupt has been serviced, and it remains outstanding
270 * indefinitely. This has the curious side effect that and no further interrupts
271 * will be generated from this device AT ALL!!.
272 * It is also desirable to clear outstanding interrupts when the device is
273 * opened/closed.
274 *
275 *
276 * Note that some devices need OUT2 to be set before they will generate
277 * interrupts at all. (Possibly tied to an internal pull-up on CTS?)
278 */
279static irqreturn_t snd_uart16550_interrupt(int irq, void *dev_id)
280{
281	struct snd_uart16550 *uart;
282
283	uart = dev_id;
284	spin_lock(&uart->open_lock);
285	if (uart->filemode == SERIAL_MODE_NOT_OPENED) {
286		spin_unlock(&uart->open_lock);
287		return IRQ_NONE;
288	}
289	/* indicate to the UART that the interrupt has been serviced */
290	inb(uart->base + UART_IIR);
291	snd_uart16550_io_loop(uart);
292	spin_unlock(&uart->open_lock);
293	return IRQ_HANDLED;
294}
295
296/* When the polling mode, this function calls snd_uart16550_io_loop. */
297static void snd_uart16550_buffer_timer(struct timer_list *t)
298{
299	unsigned long flags;
300	struct snd_uart16550 *uart;
301
302	uart = from_timer(uart, t, buffer_timer);
303	spin_lock_irqsave(&uart->open_lock, flags);
304	snd_uart16550_del_timer(uart);
305	snd_uart16550_io_loop(uart);
306	spin_unlock_irqrestore(&uart->open_lock, flags);
307}
308
309/*
310 *  this method probes, if an uart sits on given port
311 *  return 0 if found
312 *  return negative error if not found
313 */
314static int snd_uart16550_detect(struct snd_uart16550 *uart)
315{
316	unsigned long io_base = uart->base;
317	int ok;
318	unsigned char c;
319
320	/* Do some vague tests for the presence of the uart */
321	if (io_base == 0 || io_base == SNDRV_AUTO_PORT) {
322		return -ENODEV;	/* Not configured */
323	}
324
325	if (!devm_request_region(uart->card->dev, io_base, 8, "Serial MIDI")) {
326		dev_err(uart->card->dev,
327			"u16550: can't grab port 0x%lx\n", io_base);
328		return -EBUSY;
329	}
330
331	/* uart detected unless one of the following tests should fail */
332	ok = 1;
333	/* 8 data-bits, 1 stop-bit, parity off, DLAB = 0 */
334	outb(UART_LCR_WLEN8, io_base + UART_LCR); /* Line Control Register */
335	c = inb(io_base + UART_IER);
336	/* The top four bits of the IER should always == 0 */
337	if ((c & 0xf0) != 0)
338		ok = 0;		/* failed */
339
340	outb(0xaa, io_base + UART_SCR);
341	/* Write arbitrary data into the scratch reg */
342	c = inb(io_base + UART_SCR);
343	/* If it comes back, it's OK */
344	if (c != 0xaa)
345		ok = 0;		/* failed */
346
347	outb(0x55, io_base + UART_SCR);
348	/* Write arbitrary data into the scratch reg */
349	c = inb(io_base + UART_SCR);
350	/* If it comes back, it's OK */
351	if (c != 0x55)
352		ok = 0;		/* failed */
353
354	return ok;
355}
356
357static void snd_uart16550_do_open(struct snd_uart16550 * uart)
358{
359	char byte;
360
361	/* Initialize basic variables */
362	uart->buff_in_count = 0;
363	uart->buff_in = 0;
364	uart->buff_out = 0;
365	uart->fifo_limit = 1;
366	uart->fifo_count = 0;
367	uart->timer_running = 0;
368
369	outb(UART_FCR_ENABLE_FIFO	/* Enable FIFO's (if available) */
370	     | UART_FCR_CLEAR_RCVR	/* Clear receiver FIFO */
371	     | UART_FCR_CLEAR_XMIT	/* Clear transmitter FIFO */
372	     | UART_FCR_TRIGGER_4	/* Set FIFO trigger at 4-bytes */
373	/* NOTE: interrupt generated after T=(time)4-bytes
374	 * if less than UART_FCR_TRIGGER bytes received
375	 */
376	     ,uart->base + UART_FCR);	/* FIFO Control Register */
377
378	if ((inb(uart->base + UART_IIR) & 0xf0) == 0xc0)
379		uart->fifo_limit = 16;
380	if (uart->divisor != 0) {
381		uart->old_line_ctrl_reg = inb(uart->base + UART_LCR);
382		outb(UART_LCR_DLAB	/* Divisor latch access bit */
383		     ,uart->base + UART_LCR);	/* Line Control Register */
384		uart->old_divisor_lsb = inb(uart->base + UART_DLL);
385		uart->old_divisor_msb = inb(uart->base + UART_DLM);
386
387		outb(uart->divisor
388		     ,uart->base + UART_DLL);	/* Divisor Latch Low */
389		outb(0
390		     ,uart->base + UART_DLM);	/* Divisor Latch High */
391		/* DLAB is reset to 0 in next outb() */
392	}
393	/* Set serial parameters (parity off, etc) */
394	outb(UART_LCR_WLEN8	/* 8 data-bits */
395	     | 0		/* 1 stop-bit */
396	     | 0		/* parity off */
397	     | 0		/* DLAB = 0 */
398	     ,uart->base + UART_LCR);	/* Line Control Register */
399
400	switch (uart->adaptor) {
401	default:
402		outb(UART_MCR_RTS	/* Set Request-To-Send line active */
403		     | UART_MCR_DTR	/* Set Data-Terminal-Ready line active */
404		     | UART_MCR_OUT2	/* Set OUT2 - not always required, but when
405					 * it is, it is ESSENTIAL for enabling interrupts
406				 */
407		     ,uart->base + UART_MCR);	/* Modem Control Register */
408		break;
409	case SNDRV_SERIAL_MS124W_SA:
410	case SNDRV_SERIAL_MS124W_MB:
411		/* MS-124W can draw power from RTS and DTR if they
412		   are in opposite states. */ 
413		outb(UART_MCR_RTS | (0&UART_MCR_DTR) | UART_MCR_OUT2,
414		     uart->base + UART_MCR);
415		break;
416	case SNDRV_SERIAL_MS124T:
417		/* MS-124T can draw power from RTS and/or DTR (preferably
418		   both) if they are both asserted. */
419		outb(UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2,
420		     uart->base + UART_MCR);
421		break;
422	}
423
424	if (uart->irq < 0) {
425		byte = (0 & UART_IER_RDI)	/* Disable Receiver data interrupt */
426		    |(0 & UART_IER_THRI)	/* Disable Transmitter holding register empty interrupt */
427		    ;
428	} else if (uart->adaptor == SNDRV_SERIAL_MS124W_SA) {
429		byte = UART_IER_RDI	/* Enable Receiver data interrupt */
430		    | UART_IER_MSI	/* Enable Modem status interrupt */
431		    ;
432	} else if (uart->adaptor == SNDRV_SERIAL_GENERIC) {
433		byte = UART_IER_RDI	/* Enable Receiver data interrupt */
434		    | UART_IER_MSI	/* Enable Modem status interrupt */
435		    | UART_IER_THRI	/* Enable Transmitter holding register empty interrupt */
436		    ;
437	} else {
438		byte = UART_IER_RDI	/* Enable Receiver data interrupt */
439		    | UART_IER_THRI	/* Enable Transmitter holding register empty interrupt */
440		    ;
441	}
442	outb(byte, uart->base + UART_IER);	/* Interrupt enable Register */
443
444	inb(uart->base + UART_LSR);	/* Clear any pre-existing overrun indication */
445	inb(uart->base + UART_IIR);	/* Clear any pre-existing transmit interrupt */
446	inb(uart->base + UART_RX);	/* Clear any pre-existing receive interrupt */
447}
448
449static void snd_uart16550_do_close(struct snd_uart16550 * uart)
450{
451	if (uart->irq < 0)
452		snd_uart16550_del_timer(uart);
453
454	/* NOTE: may need to disable interrupts before de-registering out handler.
455	 * For now, the consequences are harmless.
456	 */
457
458	outb((0 & UART_IER_RDI)		/* Disable Receiver data interrupt */
459	     |(0 & UART_IER_THRI)	/* Disable Transmitter holding register empty interrupt */
460	     ,uart->base + UART_IER);	/* Interrupt enable Register */
461
462	switch (uart->adaptor) {
463	default:
464		outb((0 & UART_MCR_RTS)		/* Deactivate Request-To-Send line  */
465		     |(0 & UART_MCR_DTR)	/* Deactivate Data-Terminal-Ready line */
466		     |(0 & UART_MCR_OUT2)	/* Deactivate OUT2 */
467		     ,uart->base + UART_MCR);	/* Modem Control Register */
468	  break;
469	case SNDRV_SERIAL_MS124W_SA:
470	case SNDRV_SERIAL_MS124W_MB:
471		/* MS-124W can draw power from RTS and DTR if they
472		   are in opposite states; leave it powered. */ 
473		outb(UART_MCR_RTS | (0&UART_MCR_DTR) | (0&UART_MCR_OUT2),
474		     uart->base + UART_MCR);
475		break;
476	case SNDRV_SERIAL_MS124T:
477		/* MS-124T can draw power from RTS and/or DTR (preferably
478		   both) if they are both asserted; leave it powered. */
479		outb(UART_MCR_RTS | UART_MCR_DTR | (0&UART_MCR_OUT2),
480		     uart->base + UART_MCR);
481		break;
482	}
483
484	inb(uart->base + UART_IIR);	/* Clear any outstanding interrupts */
485
486	/* Restore old divisor */
487	if (uart->divisor != 0) {
488		outb(UART_LCR_DLAB		/* Divisor latch access bit */
489		     ,uart->base + UART_LCR);	/* Line Control Register */
490		outb(uart->old_divisor_lsb
491		     ,uart->base + UART_DLL);	/* Divisor Latch Low */
492		outb(uart->old_divisor_msb
493		     ,uart->base + UART_DLM);	/* Divisor Latch High */
494		/* Restore old LCR (data bits, stop bits, parity, DLAB) */
495		outb(uart->old_line_ctrl_reg
496		     ,uart->base + UART_LCR);	/* Line Control Register */
497	}
498}
499
500static int snd_uart16550_input_open(struct snd_rawmidi_substream *substream)
501{
502	unsigned long flags;
503	struct snd_uart16550 *uart = substream->rmidi->private_data;
504
505	spin_lock_irqsave(&uart->open_lock, flags);
506	if (uart->filemode == SERIAL_MODE_NOT_OPENED)
507		snd_uart16550_do_open(uart);
508	uart->filemode |= SERIAL_MODE_INPUT_OPEN;
509	uart->midi_input[substream->number] = substream;
510	spin_unlock_irqrestore(&uart->open_lock, flags);
511	return 0;
512}
513
514static int snd_uart16550_input_close(struct snd_rawmidi_substream *substream)
515{
516	unsigned long flags;
517	struct snd_uart16550 *uart = substream->rmidi->private_data;
518
519	spin_lock_irqsave(&uart->open_lock, flags);
520	uart->filemode &= ~SERIAL_MODE_INPUT_OPEN;
521	uart->midi_input[substream->number] = NULL;
522	if (uart->filemode == SERIAL_MODE_NOT_OPENED)
523		snd_uart16550_do_close(uart);
524	spin_unlock_irqrestore(&uart->open_lock, flags);
525	return 0;
526}
527
528static void snd_uart16550_input_trigger(struct snd_rawmidi_substream *substream,
529					int up)
530{
531	unsigned long flags;
532	struct snd_uart16550 *uart = substream->rmidi->private_data;
533
534	spin_lock_irqsave(&uart->open_lock, flags);
535	if (up)
536		uart->filemode |= SERIAL_MODE_INPUT_TRIGGERED;
537	else
538		uart->filemode &= ~SERIAL_MODE_INPUT_TRIGGERED;
539	spin_unlock_irqrestore(&uart->open_lock, flags);
540}
541
542static int snd_uart16550_output_open(struct snd_rawmidi_substream *substream)
543{
544	unsigned long flags;
545	struct snd_uart16550 *uart = substream->rmidi->private_data;
546
547	spin_lock_irqsave(&uart->open_lock, flags);
548	if (uart->filemode == SERIAL_MODE_NOT_OPENED)
549		snd_uart16550_do_open(uart);
550	uart->filemode |= SERIAL_MODE_OUTPUT_OPEN;
551	uart->midi_output[substream->number] = substream;
552	spin_unlock_irqrestore(&uart->open_lock, flags);
553	return 0;
554};
555
556static int snd_uart16550_output_close(struct snd_rawmidi_substream *substream)
557{
558	unsigned long flags;
559	struct snd_uart16550 *uart = substream->rmidi->private_data;
560
561	spin_lock_irqsave(&uart->open_lock, flags);
562	uart->filemode &= ~SERIAL_MODE_OUTPUT_OPEN;
563	uart->midi_output[substream->number] = NULL;
564	if (uart->filemode == SERIAL_MODE_NOT_OPENED)
565		snd_uart16550_do_close(uart);
566	spin_unlock_irqrestore(&uart->open_lock, flags);
567	return 0;
568};
569
570static inline int snd_uart16550_buffer_can_write(struct snd_uart16550 *uart,
571						 int Num)
572{
573	if (uart->buff_in_count + Num < TX_BUFF_SIZE)
574		return 1;
575	else
576		return 0;
577}
578
579static inline int snd_uart16550_write_buffer(struct snd_uart16550 *uart,
580					     unsigned char byte)
581{
582	unsigned short buff_in = uart->buff_in;
583	if (uart->buff_in_count < TX_BUFF_SIZE) {
584		uart->tx_buff[buff_in] = byte;
585		buff_in++;
586		buff_in &= TX_BUFF_MASK;
587		uart->buff_in = buff_in;
588		uart->buff_in_count++;
589		if (uart->irq < 0) /* polling mode */
590			snd_uart16550_add_timer(uart);
591		return 1;
592	} else
593		return 0;
594}
595
596static int snd_uart16550_output_byte(struct snd_uart16550 *uart,
597				     struct snd_rawmidi_substream *substream,
598				     unsigned char midi_byte)
599{
600	if (uart->buff_in_count == 0                    /* Buffer empty? */
601	    && ((uart->adaptor != SNDRV_SERIAL_MS124W_SA &&
602	    uart->adaptor != SNDRV_SERIAL_GENERIC) ||
603		(uart->fifo_count == 0                  /* FIFO empty? */
604		 && (inb(uart->base + UART_MSR) & UART_MSR_CTS)))) { /* CTS? */
605
606	        /* Tx Buffer Empty - try to write immediately */
607		if ((inb(uart->base + UART_LSR) & UART_LSR_THRE) != 0) {
608		        /* Transmitter holding register (and Tx FIFO) empty */
609		        uart->fifo_count = 1;
610			outb(midi_byte, uart->base + UART_TX);
611		} else {
612		        if (uart->fifo_count < uart->fifo_limit) {
613			        uart->fifo_count++;
614				outb(midi_byte, uart->base + UART_TX);
615			} else {
616			        /* Cannot write (buffer empty) -
617				 * put char in buffer */
618				snd_uart16550_write_buffer(uart, midi_byte);
619			}
620		}
621	} else {
622		if (!snd_uart16550_write_buffer(uart, midi_byte)) {
623			dev_warn(uart->card->dev,
624				 "%s: Buffer overrun on device at 0x%lx\n",
625				 uart->rmidi->name, uart->base);
626			return 0;
627		}
628	}
629
630	return 1;
631}
632
633static void snd_uart16550_output_write(struct snd_rawmidi_substream *substream)
634{
635	unsigned long flags;
636	unsigned char midi_byte, addr_byte;
637	struct snd_uart16550 *uart = substream->rmidi->private_data;
638	char first;
639	static unsigned long lasttime = 0;
640	
641	/* Interrupts are disabled during the updating of the tx_buff,
642	 * since it is 'bad' to have two processes updating the same
643	 * variables (ie buff_in & buff_out)
644	 */
645
646	spin_lock_irqsave(&uart->open_lock, flags);
647
648	if (uart->irq < 0)	/* polling */
649		snd_uart16550_io_loop(uart);
650
651	if (uart->adaptor == SNDRV_SERIAL_MS124W_MB) {
652		while (1) {
653			/* buffer full? */
654			/* in this mode we need two bytes of space */
655			if (uart->buff_in_count > TX_BUFF_SIZE - 2)
656				break;
657			if (snd_rawmidi_transmit(substream, &midi_byte, 1) != 1)
658				break;
659#ifdef SNDRV_SERIAL_MS124W_MB_NOCOMBO
660			/* select exactly one of the four ports */
661			addr_byte = (1 << (substream->number + 4)) | 0x08;
662#else
663			/* select any combination of the four ports */
664			addr_byte = (substream->number << 4) | 0x08;
665			/* ...except none */
666			if (addr_byte == 0x08)
667				addr_byte = 0xf8;
668#endif
669			snd_uart16550_output_byte(uart, substream, addr_byte);
670			/* send midi byte */
671			snd_uart16550_output_byte(uart, substream, midi_byte);
672		}
673	} else {
674		first = 0;
675		while (snd_rawmidi_transmit_peek(substream, &midi_byte, 1) == 1) {
676			/* Also send F5 after 3 seconds with no data
677			 * to handle device disconnect */
678			if (first == 0 &&
679			    (uart->adaptor == SNDRV_SERIAL_SOUNDCANVAS ||
680			     uart->adaptor == SNDRV_SERIAL_GENERIC) &&
681			    (uart->prev_out != substream->number ||
682			     time_after(jiffies, lasttime + 3*HZ))) {
683
684				if (snd_uart16550_buffer_can_write(uart, 3)) {
685					/* Roland Soundcanvas part selection */
686					/* If this substream of the data is
687					 * different previous substream
688					 * in this uart, send the change part
689					 * event
690					 */
691					uart->prev_out = substream->number;
692					/* change part */
693					snd_uart16550_output_byte(uart, substream,
694								  0xf5);
695					/* data */
696					snd_uart16550_output_byte(uart, substream,
697								  uart->prev_out + 1);
698					/* If midi_byte is a data byte,
699					 * send the previous status byte */
700					if (midi_byte < 0x80 &&
701					    uart->adaptor == SNDRV_SERIAL_SOUNDCANVAS)
702						snd_uart16550_output_byte(uart, substream, uart->prev_status[uart->prev_out]);
703				} else if (!uart->drop_on_full)
704					break;
705
706			}
707
708			/* send midi byte */
709			if (!snd_uart16550_output_byte(uart, substream, midi_byte) &&
710			    !uart->drop_on_full )
711				break;
712
713			if (midi_byte >= 0x80 && midi_byte < 0xf0)
714				uart->prev_status[uart->prev_out] = midi_byte;
715			first = 1;
716
717			snd_rawmidi_transmit_ack( substream, 1 );
718		}
719		lasttime = jiffies;
720	}
721	spin_unlock_irqrestore(&uart->open_lock, flags);
722}
723
724static void snd_uart16550_output_trigger(struct snd_rawmidi_substream *substream,
725					 int up)
726{
727	unsigned long flags;
728	struct snd_uart16550 *uart = substream->rmidi->private_data;
729
730	spin_lock_irqsave(&uart->open_lock, flags);
731	if (up)
732		uart->filemode |= SERIAL_MODE_OUTPUT_TRIGGERED;
733	else
734		uart->filemode &= ~SERIAL_MODE_OUTPUT_TRIGGERED;
735	spin_unlock_irqrestore(&uart->open_lock, flags);
736	if (up)
737		snd_uart16550_output_write(substream);
738}
739
740static const struct snd_rawmidi_ops snd_uart16550_output =
741{
742	.open =		snd_uart16550_output_open,
743	.close =	snd_uart16550_output_close,
744	.trigger =	snd_uart16550_output_trigger,
745};
746
747static const struct snd_rawmidi_ops snd_uart16550_input =
748{
749	.open =		snd_uart16550_input_open,
750	.close =	snd_uart16550_input_close,
751	.trigger =	snd_uart16550_input_trigger,
752};
753
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
754static int snd_uart16550_create(struct snd_card *card,
755				unsigned long iobase,
756				int irq,
757				unsigned int speed,
758				unsigned int base,
759				int adaptor,
760				int droponfull,
761				struct snd_uart16550 **ruart)
762{
 
 
 
763	struct snd_uart16550 *uart;
764	int err;
765
766
767	uart = devm_kzalloc(card->dev, sizeof(*uart), GFP_KERNEL);
768	if (!uart)
769		return -ENOMEM;
770	uart->adaptor = adaptor;
771	uart->card = card;
772	spin_lock_init(&uart->open_lock);
773	uart->irq = -1;
774	uart->base = iobase;
775	uart->drop_on_full = droponfull;
776
777	err = snd_uart16550_detect(uart);
778	if (err <= 0) {
779		dev_err(card->dev, "no UART detected at 0x%lx\n", iobase);
780		return -ENODEV;
781	}
782
783	if (irq >= 0 && irq != SNDRV_AUTO_IRQ) {
784		if (devm_request_irq(card->dev, irq, snd_uart16550_interrupt,
785				     0, "Serial MIDI", uart)) {
786			dev_warn(card->dev,
787				 "irq %d busy. Using Polling.\n", irq);
788		} else {
789			uart->irq = irq;
790		}
791	}
792	uart->divisor = base / speed;
793	uart->speed = base / (unsigned int)uart->divisor;
794	uart->speed_base = base;
795	uart->prev_out = -1;
796	uart->prev_in = 0;
797	uart->rstatus = 0;
798	memset(uart->prev_status, 0x80, sizeof(unsigned char) * SNDRV_SERIAL_MAX_OUTS);
799	timer_setup(&uart->buffer_timer, snd_uart16550_buffer_timer, 0);
 
 
800	uart->timer_running = 0;
801
 
 
 
 
 
 
802	switch (uart->adaptor) {
803	case SNDRV_SERIAL_MS124W_SA:
804	case SNDRV_SERIAL_MS124W_MB:
805		/* MS-124W can draw power from RTS and DTR if they
806		   are in opposite states. */ 
807		outb(UART_MCR_RTS | (0&UART_MCR_DTR), uart->base + UART_MCR);
808		break;
809	case SNDRV_SERIAL_MS124T:
810		/* MS-124T can draw power from RTS and/or DTR (preferably
811		   both) if they are asserted. */
812		outb(UART_MCR_RTS | UART_MCR_DTR, uart->base + UART_MCR);
813		break;
814	default:
815		break;
816	}
817
818	if (ruart)
819		*ruart = uart;
820
821	return 0;
822}
823
824static void snd_uart16550_substreams(struct snd_rawmidi_str *stream)
825{
826	struct snd_rawmidi_substream *substream;
827
828	list_for_each_entry(substream, &stream->substreams, list) {
829		sprintf(substream->name, "Serial MIDI %d", substream->number + 1);
830	}
831}
832
833static int snd_uart16550_rmidi(struct snd_uart16550 *uart, int device,
834			       int outs, int ins,
835			       struct snd_rawmidi **rmidi)
836{
837	struct snd_rawmidi *rrawmidi;
838	int err;
839
840	err = snd_rawmidi_new(uart->card, "UART Serial MIDI", device,
841			      outs, ins, &rrawmidi);
842	if (err < 0)
843		return err;
844	snd_rawmidi_set_ops(rrawmidi, SNDRV_RAWMIDI_STREAM_INPUT,
845			    &snd_uart16550_input);
846	snd_rawmidi_set_ops(rrawmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
847			    &snd_uart16550_output);
848	strcpy(rrawmidi->name, "Serial MIDI");
849	snd_uart16550_substreams(&rrawmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT]);
850	snd_uart16550_substreams(&rrawmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT]);
851	rrawmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
852			       SNDRV_RAWMIDI_INFO_INPUT |
853			       SNDRV_RAWMIDI_INFO_DUPLEX;
854	rrawmidi->private_data = uart;
855	if (rmidi)
856		*rmidi = rrawmidi;
857	return 0;
858}
859
860static int snd_serial_probe(struct platform_device *devptr)
861{
862	struct snd_card *card;
863	struct snd_uart16550 *uart;
864	int err;
865	int dev = devptr->id;
866
867	switch (adaptor[dev]) {
868	case SNDRV_SERIAL_SOUNDCANVAS:
869		ins[dev] = 1;
870		break;
871	case SNDRV_SERIAL_MS124T:
872	case SNDRV_SERIAL_MS124W_SA:
873		outs[dev] = 1;
874		ins[dev] = 1;
875		break;
876	case SNDRV_SERIAL_MS124W_MB:
877		outs[dev] = 16;
878		ins[dev] = 1;
879		break;
880	case SNDRV_SERIAL_GENERIC:
881		break;
882	default:
883		dev_err(&devptr->dev,
884			"Adaptor type is out of range 0-%d (%d)\n",
885			SNDRV_SERIAL_MAX_ADAPTOR, adaptor[dev]);
886		return -ENODEV;
887	}
888
889	if (outs[dev] < 1 || outs[dev] > SNDRV_SERIAL_MAX_OUTS) {
890		dev_err(&devptr->dev,
891			"Count of outputs is out of range 1-%d (%d)\n",
892			SNDRV_SERIAL_MAX_OUTS, outs[dev]);
893		return -ENODEV;
894	}
895
896	if (ins[dev] < 1 || ins[dev] > SNDRV_SERIAL_MAX_INS) {
897		dev_err(&devptr->dev,
898			"Count of inputs is out of range 1-%d (%d)\n",
899			SNDRV_SERIAL_MAX_INS, ins[dev]);
900		return -ENODEV;
901	}
902
903	err  = snd_devm_card_new(&devptr->dev, index[dev], id[dev], THIS_MODULE,
904				 0, &card);
905	if (err < 0)
906		return err;
907
908	strcpy(card->driver, "Serial");
909	strcpy(card->shortname, "Serial MIDI (UART16550A)");
910
911	err = snd_uart16550_create(card, port[dev], irq[dev], speed[dev],
912				   base[dev], adaptor[dev], droponfull[dev],
913				   &uart);
914	if (err < 0)
915		return err;
 
 
 
 
916
917	err = snd_uart16550_rmidi(uart, 0, outs[dev], ins[dev], &uart->rmidi);
918	if (err < 0)
919		return err;
920
921	sprintf(card->longname, "%s [%s] at %#lx, irq %d",
922		card->shortname,
923		adaptor_names[uart->adaptor],
924		uart->base,
925		uart->irq);
926
927	err = snd_card_register(card);
928	if (err < 0)
929		return err;
930
931	platform_set_drvdata(devptr, card);
932	return 0;
 
 
 
 
 
 
 
 
 
 
933}
934
935#define SND_SERIAL_DRIVER	"snd_serial_u16550"
936
937static struct platform_driver snd_serial_driver = {
938	.probe		= snd_serial_probe,
 
939	.driver		= {
940		.name	= SND_SERIAL_DRIVER,
 
941	},
942};
943
944static void snd_serial_unregister_all(void)
945{
946	int i;
947
948	for (i = 0; i < ARRAY_SIZE(devices); ++i)
949		platform_device_unregister(devices[i]);
950	platform_driver_unregister(&snd_serial_driver);
951}
952
953static int __init alsa_card_serial_init(void)
954{
955	int i, cards, err;
956
957	err = platform_driver_register(&snd_serial_driver);
958	if (err < 0)
959		return err;
960
961	cards = 0;
962	for (i = 0; i < SNDRV_CARDS; i++) {
963		struct platform_device *device;
964		if (! enable[i])
965			continue;
966		device = platform_device_register_simple(SND_SERIAL_DRIVER,
967							 i, NULL, 0);
968		if (IS_ERR(device))
969			continue;
970		if (!platform_get_drvdata(device)) {
971			platform_device_unregister(device);
972			continue;
973		}
974		devices[i] = device;
975		cards++;
976	}
977	if (! cards) {
978#ifdef MODULE
979		pr_err("serial midi soundcard not found or device busy\n");
980#endif
981		snd_serial_unregister_all();
982		return -ENODEV;
983	}
984	return 0;
985}
986
987static void __exit alsa_card_serial_exit(void)
988{
989	snd_serial_unregister_all();
990}
991
992module_init(alsa_card_serial_init)
993module_exit(alsa_card_serial_exit)