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Diffstat (limited to 'sound/drivers/serial-u16550.c')
| -rw-r--r-- | sound/drivers/serial-u16550.c | 1031 |
1 files changed, 1031 insertions, 0 deletions
diff --git a/sound/drivers/serial-u16550.c b/sound/drivers/serial-u16550.c new file mode 100644 index 000000000..3947f084d --- /dev/null +++ b/sound/drivers/serial-u16550.c @@ -0,0 +1,1031 @@ +// 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"); +MODULE_SUPPORTED_DEVICE("{{ALSA, MIDI serial u16550}}"); + +#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; + struct resource *res_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 */ + } + + uart->res_base = request_region(io_base, 8, "Serial MIDI"); + if (uart->res_base == NULL) { + 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_free(struct snd_uart16550 *uart) +{ + if (uart->irq >= 0) + free_irq(uart->irq, uart); + release_and_free_resource(uart->res_base); + kfree(uart); + return 0; +}; + +static int snd_uart16550_dev_free(struct snd_device *device) +{ + struct snd_uart16550 *uart = device->device_data; + return snd_uart16550_free(uart); +} + +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) +{ + static const struct snd_device_ops ops = { + .dev_free = snd_uart16550_dev_free, + }; + struct snd_uart16550 *uart; + int err; + + + if ((uart = kzalloc(sizeof(*uart), GFP_KERNEL)) == NULL) + 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; + + if ((err = snd_uart16550_detect(uart)) <= 0) { + printk(KERN_ERR "no UART detected at 0x%lx\n", iobase); + snd_uart16550_free(uart); + return -ENODEV; + } + + if (irq >= 0 && irq != SNDRV_AUTO_IRQ) { + if (request_irq(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; + + /* Register device */ + if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, uart, &ops)) < 0) { + snd_uart16550_free(uart); + return err; + } + + 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_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)"); + + if ((err = snd_uart16550_create(card, + port[dev], + irq[dev], + speed[dev], + base[dev], + adaptor[dev], + droponfull[dev], + &uart)) < 0) + goto _err; + + err = snd_uart16550_rmidi(uart, 0, outs[dev], ins[dev], &uart->rmidi); + if (err < 0) + goto _err; + + sprintf(card->longname, "%s [%s] at %#lx, irq %d", + card->shortname, + adaptor_names[uart->adaptor], + uart->base, + uart->irq); + + if ((err = snd_card_register(card)) < 0) + goto _err; + + platform_set_drvdata(devptr, card); + return 0; + + _err: + snd_card_free(card); + return err; +} + +static int snd_serial_remove(struct platform_device *devptr) +{ + snd_card_free(platform_get_drvdata(devptr)); + return 0; +} + +#define SND_SERIAL_DRIVER "snd_serial_u16550" + +static struct platform_driver snd_serial_driver = { + .probe = snd_serial_probe, + .remove = snd_serial_remove, + .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; + + if ((err = platform_driver_register(&snd_serial_driver)) < 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) |