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linux/sound/drivers/serial-u16550.c
Takashi Iwai 60d03de81c ALSA: serial-u16550: Allocate resources with device-managed APIs 
This patch converts the resource management in serial u16550 driver
with devres as a clean up.  Each manual resource management is
converted with the corresponding devres helper, and the card object
release is managed now via card->private_free instead of a lowlevel
snd_device.

This should give no user-visible functional changes.

Link: https://lore.kernel.org/r/20210715075941.23332-76-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-07-19 16:17:30 +02:00

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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* serial.c
* Copyright (c) by Jaroslav Kysela <perex@perex.cz>,
* Isaku Yamahata <yamahata@private.email.ne.jp>,
* George Hansper <ghansper@apana.org.au>,
* Hannu Savolainen
*
* This code is based on the code from ALSA 0.5.9, but heavily rewritten.
*
* Sat Mar 31 17:27:57 PST 2001 tim.mann@compaq.com
* Added support for the Midiator MS-124T and for the MS-124W in
* Single Addressed (S/A) or Multiple Burst (M/B) mode, with
* power derived either parasitically from the serial port or
* from a separate power supply.
*
* More documentation can be found in serial-u16550.txt.
*/
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/io.h>
#include <sound/core.h>
#include <sound/rawmidi.h>
#include <sound/initval.h>
#include <linux/serial_reg.h>
#include <linux/jiffies.h>
MODULE_DESCRIPTION("MIDI serial u16550");
MODULE_LICENSE("GPL");
#define SNDRV_SERIAL_SOUNDCANVAS 0 /* Roland Soundcanvas; F5 NN selects part */
#define SNDRV_SERIAL_MS124T 1 /* Midiator MS-124T */
#define SNDRV_SERIAL_MS124W_SA 2 /* Midiator MS-124W in S/A mode */
#define SNDRV_SERIAL_MS124W_MB 3 /* Midiator MS-124W in M/B mode */
#define SNDRV_SERIAL_GENERIC 4 /* Generic Interface */
#define SNDRV_SERIAL_MAX_ADAPTOR SNDRV_SERIAL_GENERIC
static const char * const adaptor_names[] = {
"Soundcanvas",
"MS-124T",
"MS-124W S/A",
"MS-124W M/B",
"Generic"
};
#define SNDRV_SERIAL_NORMALBUFF 0 /* Normal blocking buffer operation */
#define SNDRV_SERIAL_DROPBUFF 1 /* Non-blocking discard operation */
static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; /* Index 0-MAX */
static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; /* ID for this card */
static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE; /* Enable this card */
static long port[SNDRV_CARDS] = SNDRV_DEFAULT_PORT; /* 0x3f8,0x2f8,0x3e8,0x2e8 */
static int irq[SNDRV_CARDS] = SNDRV_DEFAULT_IRQ; /* 3,4,5,7,9,10,11,14,15 */
static int speed[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 38400}; /* 9600,19200,38400,57600,115200 */
static int base[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 115200}; /* baud base */
static int outs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1}; /* 1 to 16 */
static int ins[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1}; /* 1 to 16 */
static int adaptor[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = SNDRV_SERIAL_SOUNDCANVAS};
static bool droponfull[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS -1)] = SNDRV_SERIAL_NORMALBUFF };
module_param_array(index, int, NULL, 0444);
MODULE_PARM_DESC(index, "Index value for Serial MIDI.");
module_param_array(id, charp, NULL, 0444);
MODULE_PARM_DESC(id, "ID string for Serial MIDI.");
module_param_array(enable, bool, NULL, 0444);
MODULE_PARM_DESC(enable, "Enable UART16550A chip.");
module_param_hw_array(port, long, ioport, NULL, 0444);
MODULE_PARM_DESC(port, "Port # for UART16550A chip.");
module_param_hw_array(irq, int, irq, NULL, 0444);
MODULE_PARM_DESC(irq, "IRQ # for UART16550A chip.");
module_param_array(speed, int, NULL, 0444);
MODULE_PARM_DESC(speed, "Speed in bauds.");
module_param_array(base, int, NULL, 0444);
MODULE_PARM_DESC(base, "Base for divisor in bauds.");
module_param_array(outs, int, NULL, 0444);
MODULE_PARM_DESC(outs, "Number of MIDI outputs.");
module_param_array(ins, int, NULL, 0444);
MODULE_PARM_DESC(ins, "Number of MIDI inputs.");
module_param_array(droponfull, bool, NULL, 0444);
MODULE_PARM_DESC(droponfull, "Flag to enable drop-on-full buffer mode");
module_param_array(adaptor, int, NULL, 0444);
MODULE_PARM_DESC(adaptor, "Type of adaptor.");
/*#define SNDRV_SERIAL_MS124W_MB_NOCOMBO 1*/ /* Address outs as 0-3 instead of bitmap */
#define SNDRV_SERIAL_MAX_OUTS 16 /* max 64, min 16 */
#define SNDRV_SERIAL_MAX_INS 16 /* max 64, min 16 */
#define TX_BUFF_SIZE (1<<15) /* Must be 2^n */
#define TX_BUFF_MASK (TX_BUFF_SIZE - 1)
#define SERIAL_MODE_NOT_OPENED (0)
#define SERIAL_MODE_INPUT_OPEN (1 << 0)
#define SERIAL_MODE_OUTPUT_OPEN (1 << 1)
#define SERIAL_MODE_INPUT_TRIGGERED (1 << 2)
#define SERIAL_MODE_OUTPUT_TRIGGERED (1 << 3)
struct snd_uart16550 {
struct snd_card *card;
struct snd_rawmidi *rmidi;
struct snd_rawmidi_substream *midi_output[SNDRV_SERIAL_MAX_OUTS];
struct snd_rawmidi_substream *midi_input[SNDRV_SERIAL_MAX_INS];
int filemode; /* open status of file */
spinlock_t open_lock;
int irq;
unsigned long base;
unsigned int speed;
unsigned int speed_base;
unsigned char divisor;
unsigned char old_divisor_lsb;
unsigned char old_divisor_msb;
unsigned char old_line_ctrl_reg;
/* parameter for using of write loop */
short int fifo_limit; /* used in uart16550 */
short int fifo_count; /* used in uart16550 */
/* type of adaptor */
int adaptor;
/* inputs */
int prev_in;
unsigned char rstatus;
/* outputs */
int prev_out;
unsigned char prev_status[SNDRV_SERIAL_MAX_OUTS];
/* write buffer and its writing/reading position */
unsigned char tx_buff[TX_BUFF_SIZE];
int buff_in_count;
int buff_in;
int buff_out;
int drop_on_full;
/* wait timer */
unsigned int timer_running:1;
struct timer_list buffer_timer;
};
static struct platform_device *devices[SNDRV_CARDS];
static inline void snd_uart16550_add_timer(struct snd_uart16550 *uart)
{
if (!uart->timer_running) {
/* timer 38600bps * 10bit * 16byte */
mod_timer(&uart->buffer_timer, jiffies + (HZ + 255) / 256);
uart->timer_running = 1;
}
}
static inline void snd_uart16550_del_timer(struct snd_uart16550 *uart)
{
if (uart->timer_running) {
del_timer(&uart->buffer_timer);
uart->timer_running = 0;
}
}
/* This macro is only used in snd_uart16550_io_loop */
static inline void snd_uart16550_buffer_output(struct snd_uart16550 *uart)
{
unsigned short buff_out = uart->buff_out;
if (uart->buff_in_count > 0) {
outb(uart->tx_buff[buff_out], uart->base + UART_TX);
uart->fifo_count++;
buff_out++;
buff_out &= TX_BUFF_MASK;
uart->buff_out = buff_out;
uart->buff_in_count--;
}
}
/* This loop should be called with interrupts disabled
* We don't want to interrupt this,
* as we're already handling an interrupt
*/
static void snd_uart16550_io_loop(struct snd_uart16550 * uart)
{
unsigned char c, status;
int substream;
/* recall previous stream */
substream = uart->prev_in;
/* Read Loop */
while ((status = inb(uart->base + UART_LSR)) & UART_LSR_DR) {
/* while receive data ready */
c = inb(uart->base + UART_RX);
/* keep track of last status byte */
if (c & 0x80)
uart->rstatus = c;
/* handle stream switch */
if (uart->adaptor == SNDRV_SERIAL_GENERIC) {
if (uart->rstatus == 0xf5) {
if (c <= SNDRV_SERIAL_MAX_INS && c > 0)
substream = c - 1;
if (c != 0xf5)
/* prevent future bytes from being
interpreted as streams */
uart->rstatus = 0;
} else if ((uart->filemode & SERIAL_MODE_INPUT_OPEN)
&& uart->midi_input[substream])
snd_rawmidi_receive(uart->midi_input[substream],
&c, 1);
} else if ((uart->filemode & SERIAL_MODE_INPUT_OPEN) &&
uart->midi_input[substream])
snd_rawmidi_receive(uart->midi_input[substream], &c, 1);
if (status & UART_LSR_OE)
snd_printk(KERN_WARNING
"%s: Overrun on device at 0x%lx\n",
uart->rmidi->name, uart->base);
}
/* remember the last stream */
uart->prev_in = substream;
/* no need of check SERIAL_MODE_OUTPUT_OPEN because if not,
buffer is never filled. */
/* Check write status */
if (status & UART_LSR_THRE)
uart->fifo_count = 0;
if (uart->adaptor == SNDRV_SERIAL_MS124W_SA
|| uart->adaptor == SNDRV_SERIAL_GENERIC) {
/* Can't use FIFO, must send only when CTS is true */
status = inb(uart->base + UART_MSR);
while (uart->fifo_count == 0 && (status & UART_MSR_CTS) &&
uart->buff_in_count > 0) {
snd_uart16550_buffer_output(uart);
status = inb(uart->base + UART_MSR);
}
} else {
/* Write loop */
while (uart->fifo_count < uart->fifo_limit /* Can we write ? */
&& uart->buff_in_count > 0) /* Do we want to? */
snd_uart16550_buffer_output(uart);
}
if (uart->irq < 0 && uart->buff_in_count > 0)
snd_uart16550_add_timer(uart);
}
/* NOTES ON SERVICING INTERUPTS
* ---------------------------
* After receiving a interrupt, it is important to indicate to the UART that
* this has been done.
* For a Rx interrupt, this is done by reading the received byte.
* For a Tx interrupt this is done by either:
* a) Writing a byte
* b) Reading the IIR
* It is particularly important to read the IIR if a Tx interrupt is received
* when there is no data in tx_buff[], as in this case there no other
* indication that the interrupt has been serviced, and it remains outstanding
* indefinitely. This has the curious side effect that and no further interrupts
* will be generated from this device AT ALL!!.
* It is also desirable to clear outstanding interrupts when the device is
* opened/closed.
*
*
* Note that some devices need OUT2 to be set before they will generate
* interrupts at all. (Possibly tied to an internal pull-up on CTS?)
*/
static irqreturn_t snd_uart16550_interrupt(int irq, void *dev_id)
{
struct snd_uart16550 *uart;
uart = dev_id;
spin_lock(&uart->open_lock);
if (uart->filemode == SERIAL_MODE_NOT_OPENED) {
spin_unlock(&uart->open_lock);
return IRQ_NONE;
}
/* indicate to the UART that the interrupt has been serviced */
inb(uart->base + UART_IIR);
snd_uart16550_io_loop(uart);
spin_unlock(&uart->open_lock);
return IRQ_HANDLED;
}
/* When the polling mode, this function calls snd_uart16550_io_loop. */
static void snd_uart16550_buffer_timer(struct timer_list *t)
{
unsigned long flags;
struct snd_uart16550 *uart;
uart = from_timer(uart, t, buffer_timer);
spin_lock_irqsave(&uart->open_lock, flags);
snd_uart16550_del_timer(uart);
snd_uart16550_io_loop(uart);
spin_unlock_irqrestore(&uart->open_lock, flags);
}
/*
* this method probes, if an uart sits on given port
* return 0 if found
* return negative error if not found
*/
static int snd_uart16550_detect(struct snd_uart16550 *uart)
{
unsigned long io_base = uart->base;
int ok;
unsigned char c;
/* Do some vague tests for the presence of the uart */
if (io_base == 0 || io_base == SNDRV_AUTO_PORT) {
return -ENODEV; /* Not configured */
}
if (!devm_request_region(uart->card->dev, io_base, 8, "Serial MIDI")) {
snd_printk(KERN_ERR "u16550: can't grab port 0x%lx\n", io_base);
return -EBUSY;
}
/* uart detected unless one of the following tests should fail */
ok = 1;
/* 8 data-bits, 1 stop-bit, parity off, DLAB = 0 */
outb(UART_LCR_WLEN8, io_base + UART_LCR); /* Line Control Register */
c = inb(io_base + UART_IER);
/* The top four bits of the IER should always == 0 */
if ((c & 0xf0) != 0)
ok = 0; /* failed */
outb(0xaa, io_base + UART_SCR);
/* Write arbitrary data into the scratch reg */
c = inb(io_base + UART_SCR);
/* If it comes back, it's OK */
if (c != 0xaa)
ok = 0; /* failed */
outb(0x55, io_base + UART_SCR);
/* Write arbitrary data into the scratch reg */
c = inb(io_base + UART_SCR);
/* If it comes back, it's OK */
if (c != 0x55)
ok = 0; /* failed */
return ok;
}
static void snd_uart16550_do_open(struct snd_uart16550 * uart)
{
char byte;
/* Initialize basic variables */
uart->buff_in_count = 0;
uart->buff_in = 0;
uart->buff_out = 0;
uart->fifo_limit = 1;
uart->fifo_count = 0;
uart->timer_running = 0;
outb(UART_FCR_ENABLE_FIFO /* Enable FIFO's (if available) */
| UART_FCR_CLEAR_RCVR /* Clear receiver FIFO */
| UART_FCR_CLEAR_XMIT /* Clear transmitter FIFO */
| UART_FCR_TRIGGER_4 /* Set FIFO trigger at 4-bytes */
/* NOTE: interrupt generated after T=(time)4-bytes
* if less than UART_FCR_TRIGGER bytes received
*/
,uart->base + UART_FCR); /* FIFO Control Register */
if ((inb(uart->base + UART_IIR) & 0xf0) == 0xc0)
uart->fifo_limit = 16;
if (uart->divisor != 0) {
uart->old_line_ctrl_reg = inb(uart->base + UART_LCR);
outb(UART_LCR_DLAB /* Divisor latch access bit */
,uart->base + UART_LCR); /* Line Control Register */
uart->old_divisor_lsb = inb(uart->base + UART_DLL);
uart->old_divisor_msb = inb(uart->base + UART_DLM);
outb(uart->divisor
,uart->base + UART_DLL); /* Divisor Latch Low */
outb(0
,uart->base + UART_DLM); /* Divisor Latch High */
/* DLAB is reset to 0 in next outb() */
}
/* Set serial parameters (parity off, etc) */
outb(UART_LCR_WLEN8 /* 8 data-bits */
| 0 /* 1 stop-bit */
| 0 /* parity off */
| 0 /* DLAB = 0 */
,uart->base + UART_LCR); /* Line Control Register */
switch (uart->adaptor) {
default:
outb(UART_MCR_RTS /* Set Request-To-Send line active */
| UART_MCR_DTR /* Set Data-Terminal-Ready line active */
| UART_MCR_OUT2 /* Set OUT2 - not always required, but when
* it is, it is ESSENTIAL for enabling interrupts
*/
,uart->base + UART_MCR); /* Modem Control Register */
break;
case SNDRV_SERIAL_MS124W_SA:
case SNDRV_SERIAL_MS124W_MB:
/* MS-124W can draw power from RTS and DTR if they
are in opposite states. */
outb(UART_MCR_RTS | (0&UART_MCR_DTR) | UART_MCR_OUT2,
uart->base + UART_MCR);
break;
case SNDRV_SERIAL_MS124T:
/* MS-124T can draw power from RTS and/or DTR (preferably
both) if they are both asserted. */
outb(UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2,
uart->base + UART_MCR);
break;
}
if (uart->irq < 0) {
byte = (0 & UART_IER_RDI) /* Disable Receiver data interrupt */
|(0 & UART_IER_THRI) /* Disable Transmitter holding register empty interrupt */
;
} else if (uart->adaptor == SNDRV_SERIAL_MS124W_SA) {
byte = UART_IER_RDI /* Enable Receiver data interrupt */
| UART_IER_MSI /* Enable Modem status interrupt */
;
} else if (uart->adaptor == SNDRV_SERIAL_GENERIC) {
byte = UART_IER_RDI /* Enable Receiver data interrupt */
| UART_IER_MSI /* Enable Modem status interrupt */
| UART_IER_THRI /* Enable Transmitter holding register empty interrupt */
;
} else {
byte = UART_IER_RDI /* Enable Receiver data interrupt */
| UART_IER_THRI /* Enable Transmitter holding register empty interrupt */
;
}
outb(byte, uart->base + UART_IER); /* Interrupt enable Register */
inb(uart->base + UART_LSR); /* Clear any pre-existing overrun indication */
inb(uart->base + UART_IIR); /* Clear any pre-existing transmit interrupt */
inb(uart->base + UART_RX); /* Clear any pre-existing receive interrupt */
}
static void snd_uart16550_do_close(struct snd_uart16550 * uart)
{
if (uart->irq < 0)
snd_uart16550_del_timer(uart);
/* NOTE: may need to disable interrupts before de-registering out handler.
* For now, the consequences are harmless.
*/
outb((0 & UART_IER_RDI) /* Disable Receiver data interrupt */
|(0 & UART_IER_THRI) /* Disable Transmitter holding register empty interrupt */
,uart->base + UART_IER); /* Interrupt enable Register */
switch (uart->adaptor) {
default:
outb((0 & UART_MCR_RTS) /* Deactivate Request-To-Send line */
|(0 & UART_MCR_DTR) /* Deactivate Data-Terminal-Ready line */
|(0 & UART_MCR_OUT2) /* Deactivate OUT2 */
,uart->base + UART_MCR); /* Modem Control Register */
break;
case SNDRV_SERIAL_MS124W_SA:
case SNDRV_SERIAL_MS124W_MB:
/* MS-124W can draw power from RTS and DTR if they
are in opposite states; leave it powered. */
outb(UART_MCR_RTS | (0&UART_MCR_DTR) | (0&UART_MCR_OUT2),
uart->base + UART_MCR);
break;
case SNDRV_SERIAL_MS124T:
/* MS-124T can draw power from RTS and/or DTR (preferably
both) if they are both asserted; leave it powered. */
outb(UART_MCR_RTS | UART_MCR_DTR | (0&UART_MCR_OUT2),
uart->base + UART_MCR);
break;
}
inb(uart->base + UART_IIR); /* Clear any outstanding interrupts */
/* Restore old divisor */
if (uart->divisor != 0) {
outb(UART_LCR_DLAB /* Divisor latch access bit */
,uart->base + UART_LCR); /* Line Control Register */
outb(uart->old_divisor_lsb
,uart->base + UART_DLL); /* Divisor Latch Low */
outb(uart->old_divisor_msb
,uart->base + UART_DLM); /* Divisor Latch High */
/* Restore old LCR (data bits, stop bits, parity, DLAB) */
outb(uart->old_line_ctrl_reg
,uart->base + UART_LCR); /* Line Control Register */
}
}
static int snd_uart16550_input_open(struct snd_rawmidi_substream *substream)
{
unsigned long flags;
struct snd_uart16550 *uart = substream->rmidi->private_data;
spin_lock_irqsave(&uart->open_lock, flags);
if (uart->filemode == SERIAL_MODE_NOT_OPENED)
snd_uart16550_do_open(uart);
uart->filemode |= SERIAL_MODE_INPUT_OPEN;
uart->midi_input[substream->number] = substream;
spin_unlock_irqrestore(&uart->open_lock, flags);
return 0;
}
static int snd_uart16550_input_close(struct snd_rawmidi_substream *substream)
{
unsigned long flags;
struct snd_uart16550 *uart = substream->rmidi->private_data;
spin_lock_irqsave(&uart->open_lock, flags);
uart->filemode &= ~SERIAL_MODE_INPUT_OPEN;
uart->midi_input[substream->number] = NULL;
if (uart->filemode == SERIAL_MODE_NOT_OPENED)
snd_uart16550_do_close(uart);
spin_unlock_irqrestore(&uart->open_lock, flags);
return 0;
}
static void snd_uart16550_input_trigger(struct snd_rawmidi_substream *substream,
int up)
{
unsigned long flags;
struct snd_uart16550 *uart = substream->rmidi->private_data;
spin_lock_irqsave(&uart->open_lock, flags);
if (up)
uart->filemode |= SERIAL_MODE_INPUT_TRIGGERED;
else
uart->filemode &= ~SERIAL_MODE_INPUT_TRIGGERED;
spin_unlock_irqrestore(&uart->open_lock, flags);
}
static int snd_uart16550_output_open(struct snd_rawmidi_substream *substream)
{
unsigned long flags;
struct snd_uart16550 *uart = substream->rmidi->private_data;
spin_lock_irqsave(&uart->open_lock, flags);
if (uart->filemode == SERIAL_MODE_NOT_OPENED)
snd_uart16550_do_open(uart);
uart->filemode |= SERIAL_MODE_OUTPUT_OPEN;
uart->midi_output[substream->number] = substream;
spin_unlock_irqrestore(&uart->open_lock, flags);
return 0;
};
static int snd_uart16550_output_close(struct snd_rawmidi_substream *substream)
{
unsigned long flags;
struct snd_uart16550 *uart = substream->rmidi->private_data;
spin_lock_irqsave(&uart->open_lock, flags);
uart->filemode &= ~SERIAL_MODE_OUTPUT_OPEN;
uart->midi_output[substream->number] = NULL;
if (uart->filemode == SERIAL_MODE_NOT_OPENED)
snd_uart16550_do_close(uart);
spin_unlock_irqrestore(&uart->open_lock, flags);
return 0;
};
static inline int snd_uart16550_buffer_can_write(struct snd_uart16550 *uart,
int Num)
{
if (uart->buff_in_count + Num < TX_BUFF_SIZE)
return 1;
else
return 0;
}
static inline int snd_uart16550_write_buffer(struct snd_uart16550 *uart,
unsigned char byte)
{
unsigned short buff_in = uart->buff_in;
if (uart->buff_in_count < TX_BUFF_SIZE) {
uart->tx_buff[buff_in] = byte;
buff_in++;
buff_in &= TX_BUFF_MASK;
uart->buff_in = buff_in;
uart->buff_in_count++;
if (uart->irq < 0) /* polling mode */
snd_uart16550_add_timer(uart);
return 1;
} else
return 0;
}
static int snd_uart16550_output_byte(struct snd_uart16550 *uart,
struct snd_rawmidi_substream *substream,
unsigned char midi_byte)
{
if (uart->buff_in_count == 0 /* Buffer empty? */
&& ((uart->adaptor != SNDRV_SERIAL_MS124W_SA &&
uart->adaptor != SNDRV_SERIAL_GENERIC) ||
(uart->fifo_count == 0 /* FIFO empty? */
&& (inb(uart->base + UART_MSR) & UART_MSR_CTS)))) { /* CTS? */
/* Tx Buffer Empty - try to write immediately */
if ((inb(uart->base + UART_LSR) & UART_LSR_THRE) != 0) {
/* Transmitter holding register (and Tx FIFO) empty */
uart->fifo_count = 1;
outb(midi_byte, uart->base + UART_TX);
} else {
if (uart->fifo_count < uart->fifo_limit) {
uart->fifo_count++;
outb(midi_byte, uart->base + UART_TX);
} else {
/* Cannot write (buffer empty) -
* put char in buffer */
snd_uart16550_write_buffer(uart, midi_byte);
}
}
} else {
if (!snd_uart16550_write_buffer(uart, midi_byte)) {
snd_printk(KERN_WARNING
"%s: Buffer overrun on device at 0x%lx\n",
uart->rmidi->name, uart->base);
return 0;
}
}
return 1;
}
static void snd_uart16550_output_write(struct snd_rawmidi_substream *substream)
{
unsigned long flags;
unsigned char midi_byte, addr_byte;
struct snd_uart16550 *uart = substream->rmidi->private_data;
char first;
static unsigned long lasttime = 0;
/* Interrupts are disabled during the updating of the tx_buff,
* since it is 'bad' to have two processes updating the same
* variables (ie buff_in & buff_out)
*/
spin_lock_irqsave(&uart->open_lock, flags);
if (uart->irq < 0) /* polling */
snd_uart16550_io_loop(uart);
if (uart->adaptor == SNDRV_SERIAL_MS124W_MB) {
while (1) {
/* buffer full? */
/* in this mode we need two bytes of space */
if (uart->buff_in_count > TX_BUFF_SIZE - 2)
break;
if (snd_rawmidi_transmit(substream, &midi_byte, 1) != 1)
break;
#ifdef SNDRV_SERIAL_MS124W_MB_NOCOMBO
/* select exactly one of the four ports */
addr_byte = (1 << (substream->number + 4)) | 0x08;
#else
/* select any combination of the four ports */
addr_byte = (substream->number << 4) | 0x08;
/* ...except none */
if (addr_byte == 0x08)
addr_byte = 0xf8;
#endif
snd_uart16550_output_byte(uart, substream, addr_byte);
/* send midi byte */
snd_uart16550_output_byte(uart, substream, midi_byte);
}
} else {
first = 0;
while (snd_rawmidi_transmit_peek(substream, &midi_byte, 1) == 1) {
/* Also send F5 after 3 seconds with no data
* to handle device disconnect */
if (first == 0 &&
(uart->adaptor == SNDRV_SERIAL_SOUNDCANVAS ||
uart->adaptor == SNDRV_SERIAL_GENERIC) &&
(uart->prev_out != substream->number ||
time_after(jiffies, lasttime + 3*HZ))) {
if (snd_uart16550_buffer_can_write(uart, 3)) {
/* Roland Soundcanvas part selection */
/* If this substream of the data is
* different previous substream
* in this uart, send the change part
* event
*/
uart->prev_out = substream->number;
/* change part */
snd_uart16550_output_byte(uart, substream,
0xf5);
/* data */
snd_uart16550_output_byte(uart, substream,
uart->prev_out + 1);
/* If midi_byte is a data byte,
* send the previous status byte */
if (midi_byte < 0x80 &&
uart->adaptor == SNDRV_SERIAL_SOUNDCANVAS)
snd_uart16550_output_byte(uart, substream, uart->prev_status[uart->prev_out]);
} else if (!uart->drop_on_full)
break;
}
/* send midi byte */
if (!snd_uart16550_output_byte(uart, substream, midi_byte) &&
!uart->drop_on_full )
break;
if (midi_byte >= 0x80 && midi_byte < 0xf0)
uart->prev_status[uart->prev_out] = midi_byte;
first = 1;
snd_rawmidi_transmit_ack( substream, 1 );
}
lasttime = jiffies;
}
spin_unlock_irqrestore(&uart->open_lock, flags);
}
static void snd_uart16550_output_trigger(struct snd_rawmidi_substream *substream,
int up)
{
unsigned long flags;
struct snd_uart16550 *uart = substream->rmidi->private_data;
spin_lock_irqsave(&uart->open_lock, flags);
if (up)
uart->filemode |= SERIAL_MODE_OUTPUT_TRIGGERED;
else
uart->filemode &= ~SERIAL_MODE_OUTPUT_TRIGGERED;
spin_unlock_irqrestore(&uart->open_lock, flags);
if (up)
snd_uart16550_output_write(substream);
}
static const struct snd_rawmidi_ops snd_uart16550_output =
{
.open = snd_uart16550_output_open,
.close = snd_uart16550_output_close,
.trigger = snd_uart16550_output_trigger,
};
static const struct snd_rawmidi_ops snd_uart16550_input =
{
.open = snd_uart16550_input_open,
.close = snd_uart16550_input_close,
.trigger = snd_uart16550_input_trigger,
};
static int snd_uart16550_create(struct snd_card *card,
unsigned long iobase,
int irq,
unsigned int speed,
unsigned int base,
int adaptor,
int droponfull,
struct snd_uart16550 **ruart)
{
struct snd_uart16550 *uart;
int err;
uart = devm_kzalloc(card->dev, sizeof(*uart), GFP_KERNEL);
if (!uart)
return -ENOMEM;
uart->adaptor = adaptor;
uart->card = card;
spin_lock_init(&uart->open_lock);
uart->irq = -1;
uart->base = iobase;
uart->drop_on_full = droponfull;
err = snd_uart16550_detect(uart);
if (err <= 0) {
printk(KERN_ERR "no UART detected at 0x%lx\n", iobase);
return -ENODEV;
}
if (irq >= 0 && irq != SNDRV_AUTO_IRQ) {
if (devm_request_irq(card->dev, irq, snd_uart16550_interrupt,
0, "Serial MIDI", uart)) {
snd_printk(KERN_WARNING
"irq %d busy. Using Polling.\n", irq);
} else {
uart->irq = irq;
}
}
uart->divisor = base / speed;
uart->speed = base / (unsigned int)uart->divisor;
uart->speed_base = base;
uart->prev_out = -1;
uart->prev_in = 0;
uart->rstatus = 0;
memset(uart->prev_status, 0x80, sizeof(unsigned char) * SNDRV_SERIAL_MAX_OUTS);
timer_setup(&uart->buffer_timer, snd_uart16550_buffer_timer, 0);
uart->timer_running = 0;
switch (uart->adaptor) {
case SNDRV_SERIAL_MS124W_SA:
case SNDRV_SERIAL_MS124W_MB:
/* MS-124W can draw power from RTS and DTR if they
are in opposite states. */
outb(UART_MCR_RTS | (0&UART_MCR_DTR), uart->base + UART_MCR);
break;
case SNDRV_SERIAL_MS124T:
/* MS-124T can draw power from RTS and/or DTR (preferably
both) if they are asserted. */
outb(UART_MCR_RTS | UART_MCR_DTR, uart->base + UART_MCR);
break;
default:
break;
}
if (ruart)
*ruart = uart;
return 0;
}
static void snd_uart16550_substreams(struct snd_rawmidi_str *stream)
{
struct snd_rawmidi_substream *substream;
list_for_each_entry(substream, &stream->substreams, list) {
sprintf(substream->name, "Serial MIDI %d", substream->number + 1);
}
}
static int snd_uart16550_rmidi(struct snd_uart16550 *uart, int device,
int outs, int ins,
struct snd_rawmidi **rmidi)
{
struct snd_rawmidi *rrawmidi;
int err;
err = snd_rawmidi_new(uart->card, "UART Serial MIDI", device,
outs, ins, &rrawmidi);
if (err < 0)
return err;
snd_rawmidi_set_ops(rrawmidi, SNDRV_RAWMIDI_STREAM_INPUT,
&snd_uart16550_input);
snd_rawmidi_set_ops(rrawmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
&snd_uart16550_output);
strcpy(rrawmidi->name, "Serial MIDI");
snd_uart16550_substreams(&rrawmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT]);
snd_uart16550_substreams(&rrawmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT]);
rrawmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
SNDRV_RAWMIDI_INFO_INPUT |
SNDRV_RAWMIDI_INFO_DUPLEX;
rrawmidi->private_data = uart;
if (rmidi)
*rmidi = rrawmidi;
return 0;
}
static int snd_serial_probe(struct platform_device *devptr)
{
struct snd_card *card;
struct snd_uart16550 *uart;
int err;
int dev = devptr->id;
switch (adaptor[dev]) {
case SNDRV_SERIAL_SOUNDCANVAS:
ins[dev] = 1;
break;
case SNDRV_SERIAL_MS124T:
case SNDRV_SERIAL_MS124W_SA:
outs[dev] = 1;
ins[dev] = 1;
break;
case SNDRV_SERIAL_MS124W_MB:
outs[dev] = 16;
ins[dev] = 1;
break;
case SNDRV_SERIAL_GENERIC:
break;
default:
snd_printk(KERN_ERR
"Adaptor type is out of range 0-%d (%d)\n",
SNDRV_SERIAL_MAX_ADAPTOR, adaptor[dev]);
return -ENODEV;
}
if (outs[dev] < 1 || outs[dev] > SNDRV_SERIAL_MAX_OUTS) {
snd_printk(KERN_ERR
"Count of outputs is out of range 1-%d (%d)\n",
SNDRV_SERIAL_MAX_OUTS, outs[dev]);
return -ENODEV;
}
if (ins[dev] < 1 || ins[dev] > SNDRV_SERIAL_MAX_INS) {
snd_printk(KERN_ERR
"Count of inputs is out of range 1-%d (%d)\n",
SNDRV_SERIAL_MAX_INS, ins[dev]);
return -ENODEV;
}
err = snd_devm_card_new(&devptr->dev, index[dev], id[dev], THIS_MODULE,
0, &card);
if (err < 0)
return err;
strcpy(card->driver, "Serial");
strcpy(card->shortname, "Serial MIDI (UART16550A)");
err = snd_uart16550_create(card, port[dev], irq[dev], speed[dev],
base[dev], adaptor[dev], droponfull[dev],
&uart);
if (err < 0)
return err;
err = snd_uart16550_rmidi(uart, 0, outs[dev], ins[dev], &uart->rmidi);
if (err < 0)
return err;
sprintf(card->longname, "%s [%s] at %#lx, irq %d",
card->shortname,
adaptor_names[uart->adaptor],
uart->base,
uart->irq);
err = snd_card_register(card);
if (err < 0)
return err;
platform_set_drvdata(devptr, card);
return 0;
}
#define SND_SERIAL_DRIVER "snd_serial_u16550"
static struct platform_driver snd_serial_driver = {
.probe = snd_serial_probe,
.driver = {
.name = SND_SERIAL_DRIVER,
},
};
static void snd_serial_unregister_all(void)
{
int i;
for (i = 0; i < ARRAY_SIZE(devices); ++i)
platform_device_unregister(devices[i]);
platform_driver_unregister(&snd_serial_driver);
}
static int __init alsa_card_serial_init(void)
{
int i, cards, err;
err = platform_driver_register(&snd_serial_driver);
if (err < 0)
return err;
cards = 0;
for (i = 0; i < SNDRV_CARDS; i++) {
struct platform_device *device;
if (! enable[i])
continue;
device = platform_device_register_simple(SND_SERIAL_DRIVER,
i, NULL, 0);
if (IS_ERR(device))
continue;
if (!platform_get_drvdata(device)) {
platform_device_unregister(device);
continue;
}
devices[i] = device;
cards++;
}
if (! cards) {
#ifdef MODULE
printk(KERN_ERR "serial midi soundcard not found or device busy\n");
#endif
snd_serial_unregister_all();
return -ENODEV;
}
return 0;
}
static void __exit alsa_card_serial_exit(void)
{
snd_serial_unregister_all();
}
module_init(alsa_card_serial_init)
module_exit(alsa_card_serial_exit)
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