/*
* Stop receiving - port is in process of being closed.
*/
static void atmel_stop_rx(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
if (atmel_port->use_dma_rx) {
UART_PUT_PTCR(port, ATMEL_PDC_RXTDIS); /* disable PDC receive */
UART_PUT_IDR(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
}
else
UART_PUT_IDR(port, ATMEL_US_RXRDY);
}
/*
* Stop transmitting.
*/
static void atmel_stop_tx(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
if (atmel_port->use_dma_tx) {
UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS); /* disable PDC transmit */
UART_PUT_IDR(port, ATMEL_US_ENDTX | ATMEL_US_TXBUFE);
}
else
UART_PUT_IDR(port, ATMEL_US_TXRDY);
}
/*
* The PDC transmitter is idle, so either start the next transfer or
* disable the transmitter.
*/
static void atmel_pdc_txbufe(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
struct circ_buf *xmit = &port->info->xmit;
struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx;
int count;
if (!uart_circ_empty(xmit)) {
/* more to transmit - setup next transfer */
UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS); /* disable PDC transmit */
dma_sync_single_for_device(port->dev, pdc->dma_addr, pdc->dma_size, DMA_TO_DEVICE);
if (xmit->tail < xmit->head)
count = xmit->head - xmit->tail;
else
count = SERIAL_XMIT_SIZE - xmit->tail;
pdc->ofs = count;
UART_PUT_TPR(port, pdc->dma_addr + xmit->tail);
UART_PUT_TCR(port, count);
UART_PUT_PTCR(port, ATMEL_PDC_TXTEN); /* re-enable PDC transmit */
}
else {
/* nothing left to transmit - disable the transmitter */
UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS); /* disable PDC transmit */
UART_PUT_IDR(port, ATMEL_US_ENDTX | ATMEL_US_TXBUFE);
}
}
static int __init at91_console_setup(struct console *co, char *options)
{
struct uart_port *port;
int baud = 115200;
int bits = 8;
int parity = 'n';
int flow = 'n';
/*
* Check whether an invalid uart number has been specified, and
* if so, search for the first available port that does have
* console support.
*/
port = uart_get_console(at91_ports, AT91_NR_UART, co);
/*
* Enable the serial console, in-case bootloader did not do it.
*/
at91_sys_write(AT91_PMC_PCER, 1 << port->irq); /* enable clock */
UART_PUT_IDR(port, -1); /* disable interrupts */
UART_PUT_CR(port, AT91_US_RSTSTA | AT91_US_RSTRX);
UART_PUT_CR(port, AT91_US_TXEN | AT91_US_RXEN);
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
else
at91_console_get_options(port, &baud, &parity, &bits);
return uart_set_options(port, co, baud, parity, bits, flow);
}
/*
* Interrupt handler
*/
static irqreturn_t atmel_interrupt(int irq, void *dev_id)
{
struct uart_port *port = dev_id;
struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
unsigned int status, pending, pass_counter = 0;
status = UART_GET_CSR(port);
pending = status & UART_GET_IMR(port);
while (pending) {
/* PDC receive */
if (pending & ATMEL_US_ENDRX)
atmel_pdc_endrx(port);
if (pending & ATMEL_US_TIMEOUT)
atmel_pdc_timeout(port);
if (atmel_port->use_dma_rx && pending & (ATMEL_US_RXBRK | ATMEL_US_OVRE | ATMEL_US_FRAME | ATMEL_US_PARE))
atmel_pdc_rxerr(port, pending);
/* Interrupt receive */
if (pending & ATMEL_US_RXRDY)
atmel_rx_chars(port);
else if (pending & ATMEL_US_RXBRK) {
/*
* End of break detected. If it came along
* with a character, atmel_rx_chars will
* handle it.
*/
UART_PUT_CR(port, ATMEL_US_RSTSTA);
UART_PUT_IDR(port, ATMEL_US_RXBRK);
atmel_port->break_active = 0;
}
// TODO: All reads to CSR will clear these interrupts!
if (pending & ATMEL_US_RIIC) port->icount.rng++;
if (pending & ATMEL_US_DSRIC) port->icount.dsr++;
if (pending & ATMEL_US_DCDIC)
uart_handle_dcd_change(port, !(status & ATMEL_US_DCD));
if (pending & ATMEL_US_CTSIC)
uart_handle_cts_change(port, !(status & ATMEL_US_CTS));
if (pending & (ATMEL_US_RIIC | ATMEL_US_DSRIC | ATMEL_US_DCDIC | ATMEL_US_CTSIC))
wake_up_interruptible(&port->info->delta_msr_wait);
/* PDC transmit */
if (pending & ATMEL_US_ENDTX)
atmel_pdc_endtx(port);
if (pending & ATMEL_US_TXBUFE)
atmel_pdc_txbufe(port);
/* Interrupt transmit */
if (pending & ATMEL_US_TXRDY)
atmel_tx_chars(port);
if (pass_counter++ > ATMEL_ISR_PASS_LIMIT)
break;
status = UART_GET_CSR(port);
pending = status & UART_GET_IMR(port);
}
return IRQ_HANDLED;
}
/*
* Disable the port
*/
static void atmel_shutdown(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
/*
* Ensure everything is stopped.
*/
atmel_stop_rx(port);
atmel_stop_tx(port);
/*
* Shut-down the DMA.
*/
if (atmel_port->use_dma_rx) {
int i;
for (i = 0; i < 2; i++) {
struct atmel_dma_buffer *pdc = &atmel_port->pdc_rx[i];
dma_unmap_single(port->dev, pdc->dma_addr, pdc->dma_size, DMA_FROM_DEVICE);
kfree(pdc->buf);
}
}
if (atmel_port->use_dma_tx) {
struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx;
dma_unmap_single(port->dev, pdc->dma_addr, pdc->dma_size, DMA_TO_DEVICE);
}
/*
* Disable all interrupts, port and break condition.
*/
UART_PUT_CR(port, ATMEL_US_RSTSTA);
UART_PUT_IDR(port, -1);
/*
* Free the interrupt
*/
free_irq(port->irq, port);
/*
* If there is a specific "close" function (to unregister
* control line interrupts)
*/
if (atmel_close_hook)
atmel_close_hook(port);
}
/*
* Perform initialization and enable port for reception
*/
static int atmel_startup(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
int retval;
/*
* Ensure that no interrupts are enabled otherwise when
* request_irq() is called we could get stuck trying to
* handle an unexpected interrupt
*/
UART_PUT_IDR(port, -1);
/*
* Allocate the IRQ
*/
retval = request_irq(port->irq, atmel_interrupt, IRQF_SHARED, "atmel_serial", port);
if (retval) {
printk("atmel_serial: atmel_startup - Can't get irq\n");
return retval;
}
/*
* If there is a specific "open" function (to register
* control line interrupts)
*/
if (atmel_open_hook) {
retval = atmel_open_hook(port);
if (retval) {
free_irq(port->irq, port);
return retval;
}
}
/*
* Finally, enable the serial port
*/
UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN); /* enable xmit & rcvr */
UART_PUT_IER(port, ATMEL_US_RXRDY); /* enable receive only */
return 0;
}
/*
* Perform initialization and enable port for reception
*/
static int at91_startup(struct uart_port *port)
{
int retval;
/*
* Ensure that no interrupts are enabled otherwise when
* request_irq() is called we could get stuck trying to
* handle an unexpected interrupt
*/
UART_PUT_IDR(port, -1);
/*
* Allocate the IRQ
*/
retval = request_irq(port->irq, at91_interrupt, SA_SHIRQ, "at91_serial", port);
if (retval) {
printk("at91_serial: at91_startup - Can't get irq\n");
return retval;
}
/*
* If there is a specific "open" function (to register
* control line interrupts)
*/
if (at91_open) {
retval = at91_open(port);
if (retval) {
free_irq(port->irq, port);
return retval;
}
}
port->read_status_mask = AT91_US_RXRDY | AT91_US_TXRDY | AT91_US_OVRE
| AT91_US_FRAME | AT91_US_PARE | AT91_US_RXBRK;
/*
* Finally, enable the serial port
*/
UART_PUT_CR(port, AT91_US_RSTSTA | AT91_US_RSTRX);
UART_PUT_CR(port, AT91_US_TXEN | AT91_US_RXEN); /* enable xmit & rcvr */
UART_PUT_IER(port, AT91_US_RXRDY); /* do receive only */
return 0;
}
/*
* Disable the port
*/
static void at91_shutdown(struct uart_port *port)
{
/*
* Disable all interrupts, port and break condition.
*/
UART_PUT_CR(port, AT91_US_RSTSTA);
UART_PUT_IDR(port, -1);
/*
* Free the interrupt
*/
free_irq(port->irq, port);
/*
* If there is a specific "close" function (to unregister
* control line interrupts)
*/
if (at91_close)
at91_close(port);
}
/*
* Interrupts are disabled on entering
*/
static void atmel_console_write(struct console *co, const char *s, u_int count)
{
struct uart_port *port = &atmel_ports[co->index].uart;
unsigned int status, imr;
/*
* First, save IMR and then disable interrupts
*/
imr = UART_GET_IMR(port); /* get interrupt mask */
UART_PUT_IDR(port, ATMEL_US_RXRDY | ATMEL_US_TXRDY);
uart_console_write(port, s, count, atmel_console_putchar);
/*
* Finally, wait for transmitter to become empty
* and restore IMR
*/
do {
status = UART_GET_CSR(port);
} while (!(status & ATMEL_US_TXRDY));
UART_PUT_IER(port, imr); /* set interrupts back the way they were */
}
static int __init atmel_console_setup(struct console *co, char *options)
{
struct uart_port *port = &atmel_ports[co->index].uart;
int baud = 115200;
int bits = 8;
int parity = 'n';
int flow = 'n';
if (port->membase == 0) /* Port not initialized yet - delay setup */
return -ENODEV;
UART_PUT_IDR(port, -1); /* disable interrupts */
UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN);
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
else
atmel_console_get_options(port, &baud, &parity, &bits);
return uart_set_options(port, co, baud, parity, bits, flow);
}
/*
* Interrupts are disabled on entering
*/
static void at91_console_write(struct console *co, const char *s, u_int count)
{
struct uart_port *port = at91_ports + co->index;
unsigned int status, i, imr;
/*
* First, save IMR and then disable interrupts
*/
imr = UART_GET_IMR(port); /* get interrupt mask */
UART_PUT_IDR(port, AT91_US_RXRDY | AT91_US_TXRDY);
/*
* Now, do each character
*/
for (i = 0; i < count; i++) {
do {
status = UART_GET_CSR(port);
} while (!(status & AT91_US_TXRDY));
UART_PUT_CHAR(port, s[i]);
if (s[i] == '\n') {
do {
status = UART_GET_CSR(port);
} while (!(status & AT91_US_TXRDY));
UART_PUT_CHAR(port, '\r');
}
}
/*
* Finally, wait for transmitter to become empty
* and restore IMR
*/
do {
status = UART_GET_CSR(port);
} while (!(status & AT91_US_TXRDY));
UART_PUT_IER(port, imr); /* set interrupts back the way they were */
}
/*
* Perform initialization and enable port for reception
*/
static int atmel_startup(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
int retval;
/*
* Ensure that no interrupts are enabled otherwise when
* request_irq() is called we could get stuck trying to
* handle an unexpected interrupt
*/
UART_PUT_IDR(port, -1);
/*
* Allocate the IRQ
*/
retval = request_irq(port->irq, atmel_interrupt, IRQF_SHARED, "atmel_serial", port);
if (retval) {
printk("atmel_serial: atmel_startup - Can't get irq\n");
return retval;
}
/*
* Initialize DMA (if necessary)
*/
if (atmel_port->use_dma_rx) {
int i;
u32 pdc_buffer_size;
#ifdef INFRAD_NO_PDC_SUPPORT
struct tty_struct *tty = port->info->tty;
printk ("petworm: serial open index is %d.\n", tty->index);
if (tty->index == 2)
{
printk ("petworm: DMA buffer is 16.\n");
pdc_buffer_size = 16;
}
else
pdc_buffer_size = PDC_BUFFER_SIZE;
#else
pdc_buffer_size = PDC_BUFFER_SIZE;
#endif
for (i = 0; i < 2; i++) {
struct atmel_dma_buffer *pdc = &atmel_port->pdc_rx[i];
pdc->buf = kmalloc(pdc_buffer_size, GFP_KERNEL);
if (pdc->buf == NULL) {
if (i != 0) {
dma_unmap_single(port->dev, atmel_port->pdc_rx[0].dma_addr, pdc_buffer_size, DMA_FROM_DEVICE);
kfree(atmel_port->pdc_rx[0].buf);
}
free_irq(port->irq, port);
return -ENOMEM;
}
pdc->dma_addr = dma_map_single(port->dev, pdc->buf, pdc_buffer_size, DMA_FROM_DEVICE);
pdc->dma_size = pdc_buffer_size;
pdc->ofs = 0;
}
atmel_port->pdc_rx_idx = 0;
UART_PUT_RPR(port, atmel_port->pdc_rx[0].dma_addr);
UART_PUT_RCR(port, pdc_buffer_size);
UART_PUT_RNPR(port, atmel_port->pdc_rx[1].dma_addr);
UART_PUT_RNCR(port, pdc_buffer_size);
}
if (atmel_port->use_dma_tx) {
struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx;
struct circ_buf *xmit = &port->info->xmit;
pdc->buf = xmit->buf;
pdc->dma_addr = dma_map_single(port->dev, pdc->buf, SERIAL_XMIT_SIZE, DMA_TO_DEVICE);
pdc->dma_size = SERIAL_XMIT_SIZE;
pdc->ofs = 0;
}
/*
* If there is a specific "open" function (to register
* control line interrupts)
*/
if (atmel_open_hook) {
retval = atmel_open_hook(port);
if (retval) {
free_irq(port->irq, port);
return retval;
}
}
/*
* Finally, enable the serial port
*/
UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN); /* enable xmit & rcvr */
if (atmel_port->use_dma_rx) {
UART_PUT_RTOR(port, PDC_RX_TIMEOUT); /* set UART timeout */
UART_PUT_CR(port, ATMEL_US_STTTO);
UART_PUT_IER(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
UART_PUT_PTCR(port, ATMEL_PDC_RXTEN); /* enable PDC controller */
}
else
UART_PUT_IER(port, ATMEL_US_RXRDY); /* enable receive only */
return 0;
}
/*
* Characters received (called from interrupt handler)
*/
static void atmel_rx_chars(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
struct tty_struct *tty = port->info->tty;
unsigned int status, ch, flg;
status = UART_GET_CSR(port);
while (status & ATMEL_US_RXRDY) {
ch = UART_GET_CHAR(port);
port->icount.rx++;
flg = TTY_NORMAL;
/*
* note that the error handling code is
* out of the main execution path
*/
if (unlikely(status & (ATMEL_US_PARE | ATMEL_US_FRAME
| ATMEL_US_OVRE | ATMEL_US_RXBRK)
|| atmel_port->break_active)) {
UART_PUT_CR(port, ATMEL_US_RSTSTA); /* clear error */
if (status & ATMEL_US_RXBRK
&& !atmel_port->break_active) {
status &= ~(ATMEL_US_PARE | ATMEL_US_FRAME); /* ignore side-effect */
port->icount.brk++;
atmel_port->break_active = 1;
UART_PUT_IER(port, ATMEL_US_RXBRK);
if (uart_handle_break(port))
goto ignore_char;
} else {
/*
* This is either the end-of-break
* condition or we've received at
* least one character without RXBRK
* being set. In both cases, the next
* RXBRK will indicate start-of-break.
*/
UART_PUT_IDR(port, ATMEL_US_RXBRK);
status &= ~ATMEL_US_RXBRK;
atmel_port->break_active = 0;
}
if (status & ATMEL_US_PARE)
port->icount.parity++;
if (status & ATMEL_US_FRAME)
port->icount.frame++;
if (status & ATMEL_US_OVRE)
port->icount.overrun++;
status &= port->read_status_mask;
if (status & ATMEL_US_RXBRK)
flg = TTY_BREAK;
else if (status & ATMEL_US_PARE)
flg = TTY_PARITY;
else if (status & ATMEL_US_FRAME)
flg = TTY_FRAME;
}
if (uart_handle_sysrq_char(port, ch))
goto ignore_char;
uart_insert_char(port, status, ATMEL_US_OVRE, ch, flg);
ignore_char:
status = UART_GET_CSR(port);
}
tty_flip_buffer_push(tty);
}
/*
* Stop receiving - port is in process of being closed.
*/
static void at91_stop_rx(struct uart_port *port)
{
UART_PUT_IDR(port, AT91_US_RXRDY);
}
/*
* Stop receiving - port is in process of being closed.
*/
static void atmel_stop_rx(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
UART_PUT_IDR(port, ATMEL_US_RXRDY);
}
/*
* Change the port parameters
*/
static void atmel_set_termios(struct uart_port *port, struct ktermios * termios, struct ktermios * old)
{
struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
unsigned long flags;
unsigned int mode, imr, quot, baud;
/* Get current mode register */
mode = UART_GET_MR(port) & ~(ATMEL_US_USCLKS | ATMEL_US_CHRL | ATMEL_US_NBSTOP | ATMEL_US_PAR);
baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
quot = uart_get_divisor(port, baud);
if (quot > 65535) { /* BRGR is 16-bit, so switch to slower clock */
quot /= 8;
mode |= ATMEL_US_USCLKS_MCK_DIV8;
}
/* byte size */
switch (termios->c_cflag & CSIZE) {
case CS5:
mode |= ATMEL_US_CHRL_5;
break;
case CS6:
mode |= ATMEL_US_CHRL_6;
break;
case CS7:
mode |= ATMEL_US_CHRL_7;
break;
default:
mode |= ATMEL_US_CHRL_8;
break;
}
/* stop bits */
if (termios->c_cflag & CSTOPB)
mode |= ATMEL_US_NBSTOP_2;
/* parity */
if (termios->c_cflag & PARENB) {
if (termios->c_cflag & CMSPAR) { /* Mark or Space parity */
if (termios->c_cflag & PARODD)
mode |= ATMEL_US_PAR_MARK;
else
mode |= ATMEL_US_PAR_SPACE;
}
else if (termios->c_cflag & PARODD)
mode |= ATMEL_US_PAR_ODD;
else
mode |= ATMEL_US_PAR_EVEN;
}
else
mode |= ATMEL_US_PAR_NONE;
spin_lock_irqsave(&port->lock, flags);
port->read_status_mask = ATMEL_US_OVRE;
if (termios->c_iflag & INPCK)
port->read_status_mask |= (ATMEL_US_FRAME | ATMEL_US_PARE);
if (termios->c_iflag & (BRKINT | PARMRK))
port->read_status_mask |= ATMEL_US_RXBRK;
if (atmel_port->use_dma_rx) /* need to enable error interrupts */
UART_PUT_IER(port, port->read_status_mask);
/*
* Characters to ignore
*/
port->ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |= (ATMEL_US_FRAME | ATMEL_US_PARE);
if (termios->c_iflag & IGNBRK) {
port->ignore_status_mask |= ATMEL_US_RXBRK;
/*
* If we're ignoring parity and break indicators,
* ignore overruns too (for real raw support).
*/
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |= ATMEL_US_OVRE;
}
// TODO: Ignore all characters if CREAD is set.
/* update the per-port timeout */
uart_update_timeout(port, termios->c_cflag, baud);
/* disable interrupts and drain transmitter */
imr = UART_GET_IMR(port); /* get interrupt mask */
UART_PUT_IDR(port, -1); /* disable all interrupts */
while (!(UART_GET_CSR(port) & ATMEL_US_TXEMPTY))
cpu_relax();
/* disable receiver and transmitter */
UART_PUT_CR(port, ATMEL_US_TXDIS | ATMEL_US_RXDIS);
/* set the parity, stop bits and data size */
UART_PUT_MR(port, mode);
/* set the baud rate */
UART_PUT_BRGR(port, quot);
UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN);
/* restore interrupts */
UART_PUT_IER(port, imr);
/* CTS flow-control and modem-status interrupts */
if (UART_ENABLE_MS(port, termios->c_cflag))
port->ops->enable_ms(port);
spin_unlock_irqrestore(&port->lock, flags);
}
/*
* Stop transmitting.
*/
static void at91_stop_tx(struct uart_port *port)
{
UART_PUT_IDR(port, AT91_US_TXRDY);
port->read_status_mask &= ~AT91_US_TXRDY;
}
