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Diffstat (limited to 'drivers/serial/at91_serial.c')
-rw-r--r--drivers/serial/at91_serial.c894
1 files changed, 894 insertions, 0 deletions
diff --git a/drivers/serial/at91_serial.c b/drivers/serial/at91_serial.c
new file mode 100644
index 00000000000..0e206063d68
--- /dev/null
+++ b/drivers/serial/at91_serial.c
@@ -0,0 +1,894 @@
+/*
+ * linux/drivers/char/at91_serial.c
+ *
+ * Driver for Atmel AT91RM9200 Serial ports
+ *
+ * Copyright (C) 2003 Rick Bronson
+ *
+ * Based on drivers/char/serial_sa1100.c, by Deep Blue Solutions Ltd.
+ * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/tty.h>
+#include <linux/ioport.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/serial.h>
+#include <linux/console.h>
+#include <linux/sysrq.h>
+#include <linux/tty_flip.h>
+
+#include <asm/io.h>
+
+#include <asm/arch/at91rm9200_usart.h>
+#include <asm/mach/serial_at91rm9200.h>
+#include <asm/arch/board.h>
+#include <asm/arch/pio.h>
+
+
+#if defined(CONFIG_SERIAL_AT91_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/serial_core.h>
+
+#ifdef CONFIG_SERIAL_AT91_TTYAT
+
+/* Use device name ttyAT, major 204 and minor 154-169. This is necessary if we
+ * should coexist with the 8250 driver, such as if we have an external 16C550
+ * UART. */
+#define SERIAL_AT91_MAJOR 204
+#define MINOR_START 154
+#define AT91_DEVICENAME "ttyAT"
+
+#else
+
+/* Use device name ttyS, major 4, minor 64-68. This is the usual serial port
+ * name, but it is legally reserved for the 8250 driver. */
+#define SERIAL_AT91_MAJOR TTY_MAJOR
+#define MINOR_START 64
+#define AT91_DEVICENAME "ttyS"
+
+#endif
+
+#define AT91_VA_BASE_DBGU ((unsigned long) AT91_VA_BASE_SYS + AT91_DBGU)
+#define AT91_ISR_PASS_LIMIT 256
+
+#define UART_PUT_CR(port,v) writel(v, (port)->membase + AT91_US_CR)
+#define UART_GET_MR(port) readl((port)->membase + AT91_US_MR)
+#define UART_PUT_MR(port,v) writel(v, (port)->membase + AT91_US_MR)
+#define UART_PUT_IER(port,v) writel(v, (port)->membase + AT91_US_IER)
+#define UART_PUT_IDR(port,v) writel(v, (port)->membase + AT91_US_IDR)
+#define UART_GET_IMR(port) readl((port)->membase + AT91_US_IMR)
+#define UART_GET_CSR(port) readl((port)->membase + AT91_US_CSR)
+#define UART_GET_CHAR(port) readl((port)->membase + AT91_US_RHR)
+#define UART_PUT_CHAR(port,v) writel(v, (port)->membase + AT91_US_THR)
+#define UART_GET_BRGR(port) readl((port)->membase + AT91_US_BRGR)
+#define UART_PUT_BRGR(port,v) writel(v, (port)->membase + AT91_US_BRGR)
+#define UART_PUT_RTOR(port,v) writel(v, (port)->membase + AT91_US_RTOR)
+
+// #define UART_GET_CR(port) readl((port)->membase + AT91_US_CR) // is write-only
+
+ /* PDC registers */
+#define UART_PUT_PTCR(port,v) writel(v, (port)->membase + AT91_PDC_PTCR)
+#define UART_PUT_RPR(port,v) writel(v, (port)->membase + AT91_PDC_RPR)
+#define UART_PUT_RCR(port,v) writel(v, (port)->membase + AT91_PDC_RCR)
+#define UART_GET_RCR(port) readl((port)->membase + AT91_PDC_RCR)
+#define UART_PUT_RNPR(port,v) writel(v, (port)->membase + AT91_PDC_RNPR)
+#define UART_PUT_RNCR(port,v) writel(v, (port)->membase + AT91_PDC_RNCR)
+
+
+static int (*at91_open)(struct uart_port *);
+static void (*at91_close)(struct uart_port *);
+
+#ifdef SUPPORT_SYSRQ
+static struct console at91_console;
+#endif
+
+/*
+ * Return TIOCSER_TEMT when transmitter FIFO and Shift register is empty.
+ */
+static u_int at91_tx_empty(struct uart_port *port)
+{
+ return (UART_GET_CSR(port) & AT91_US_TXEMPTY) ? TIOCSER_TEMT : 0;
+}
+
+/*
+ * Set state of the modem control output lines
+ */
+static void at91_set_mctrl(struct uart_port *port, u_int mctrl)
+{
+ unsigned int control = 0;
+
+ /*
+ * Errata #39: RTS0 is not internally connected to PA21. We need to drive
+ * the pin manually.
+ */
+ if (port->mapbase == AT91_VA_BASE_US0) {
+ if (mctrl & TIOCM_RTS)
+ at91_sys_write(AT91_PIOA + PIO_CODR, AT91_PA21_RTS0);
+ else
+ at91_sys_write(AT91_PIOA + PIO_SODR, AT91_PA21_RTS0);
+ }
+
+ if (mctrl & TIOCM_RTS)
+ control |= AT91_US_RTSEN;
+ else
+ control |= AT91_US_RTSDIS;
+
+ if (mctrl & TIOCM_DTR)
+ control |= AT91_US_DTREN;
+ else
+ control |= AT91_US_DTRDIS;
+
+ UART_PUT_CR(port,control);
+}
+
+/*
+ * Get state of the modem control input lines
+ */
+static u_int at91_get_mctrl(struct uart_port *port)
+{
+ unsigned int status, ret = 0;
+
+ status = UART_GET_CSR(port);
+
+ /*
+ * The control signals are active low.
+ */
+ if (!(status & AT91_US_DCD))
+ ret |= TIOCM_CD;
+ if (!(status & AT91_US_CTS))
+ ret |= TIOCM_CTS;
+ if (!(status & AT91_US_DSR))
+ ret |= TIOCM_DSR;
+ if (!(status & AT91_US_RI))
+ ret |= TIOCM_RI;
+
+ return ret;
+}
+
+/*
+ * 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;
+}
+
+/*
+ * Start transmitting.
+ */
+static void at91_start_tx(struct uart_port *port)
+{
+ port->read_status_mask |= AT91_US_TXRDY;
+ UART_PUT_IER(port, AT91_US_TXRDY);
+}
+
+/*
+ * 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);
+}
+
+/*
+ * Enable modem status interrupts
+ */
+static void at91_enable_ms(struct uart_port *port)
+{
+ port->read_status_mask |= (AT91_US_RIIC | AT91_US_DSRIC | AT91_US_DCDIC | AT91_US_CTSIC);
+ UART_PUT_IER(port, AT91_US_RIIC | AT91_US_DSRIC | AT91_US_DCDIC | AT91_US_CTSIC);
+}
+
+/*
+ * Control the transmission of a break signal
+ */
+static void at91_break_ctl(struct uart_port *port, int break_state)
+{
+ if (break_state != 0)
+ UART_PUT_CR(port, AT91_US_STTBRK); /* start break */
+ else
+ UART_PUT_CR(port, AT91_US_STPBRK); /* stop break */
+}
+
+/*
+ * Characters received (called from interrupt handler)
+ */
+static void at91_rx_chars(struct uart_port *port, struct pt_regs *regs)
+{
+ struct tty_struct *tty = port->info->tty;
+ unsigned int status, ch, flg;
+
+ status = UART_GET_CSR(port) & port->read_status_mask;
+ while (status & (AT91_US_RXRDY)) {
+ ch = UART_GET_CHAR(port);
+
+ if (tty->flip.count >= TTY_FLIPBUF_SIZE)
+ goto ignore_char;
+ port->icount.rx++;
+
+ flg = TTY_NORMAL;
+
+ /*
+ * note that the error handling code is
+ * out of the main execution path
+ */
+ if (unlikely(status & (AT91_US_PARE | AT91_US_FRAME | AT91_US_OVRE))) {
+ UART_PUT_CR(port, AT91_US_RSTSTA); /* clear error */
+ if (status & (AT91_US_PARE))
+ port->icount.parity++;
+ if (status & (AT91_US_FRAME))
+ port->icount.frame++;
+ if (status & (AT91_US_OVRE))
+ port->icount.overrun++;
+
+ if (status & AT91_US_PARE)
+ flg = TTY_PARITY;
+ else if (status & AT91_US_FRAME)
+ flg = TTY_FRAME;
+ if (status & AT91_US_OVRE) {
+ /*
+ * overrun does *not* affect the character
+ * we read from the FIFO
+ */
+ tty_insert_flip_char(tty, ch, flg);
+ ch = 0;
+ flg = TTY_OVERRUN;
+ }
+#ifdef SUPPORT_SYSRQ
+ port->sysrq = 0;
+#endif
+ }
+
+ if (uart_handle_sysrq_char(port, ch, regs))
+ goto ignore_char;
+
+ tty_insert_flip_char(tty, ch, flg);
+
+ ignore_char:
+ status = UART_GET_CSR(port) & port->read_status_mask;
+ }
+
+ tty_flip_buffer_push(tty);
+}
+
+/*
+ * Transmit characters (called from interrupt handler)
+ */
+static void at91_tx_chars(struct uart_port *port)
+{
+ struct circ_buf *xmit = &port->info->xmit;
+
+ if (port->x_char) {
+ UART_PUT_CHAR(port, port->x_char);
+ port->icount.tx++;
+ port->x_char = 0;
+ return;
+ }
+ if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
+ at91_stop_tx(port);
+ return;
+ }
+
+ while (UART_GET_CSR(port) & AT91_US_TXRDY) {
+ UART_PUT_CHAR(port, xmit->buf[xmit->tail]);
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ port->icount.tx++;
+ if (uart_circ_empty(xmit))
+ break;
+ }
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(port);
+
+ if (uart_circ_empty(xmit))
+ at91_stop_tx(port);
+}
+
+/*
+ * Interrupt handler
+ */
+static irqreturn_t at91_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+ struct uart_port *port = dev_id;
+ unsigned int status, pending, pass_counter = 0;
+
+ status = UART_GET_CSR(port);
+ pending = status & port->read_status_mask;
+ if (pending) {
+ do {
+ if (pending & AT91_US_RXRDY)
+ at91_rx_chars(port, regs);
+
+ /* Clear the relevent break bits */
+ if (pending & AT91_US_RXBRK) {
+ UART_PUT_CR(port, AT91_US_RSTSTA);
+ port->icount.brk++;
+ uart_handle_break(port);
+ }
+
+ // TODO: All reads to CSR will clear these interrupts!
+ if (pending & AT91_US_RIIC) port->icount.rng++;
+ if (pending & AT91_US_DSRIC) port->icount.dsr++;
+ if (pending & AT91_US_DCDIC)
+ uart_handle_dcd_change(port, !(status & AT91_US_DCD));
+ if (pending & AT91_US_CTSIC)
+ uart_handle_cts_change(port, !(status & AT91_US_CTS));
+ if (pending & (AT91_US_RIIC | AT91_US_DSRIC | AT91_US_DCDIC | AT91_US_CTSIC))
+ wake_up_interruptible(&port->info->delta_msr_wait);
+
+ if (pending & AT91_US_TXRDY)
+ at91_tx_chars(port);
+ if (pass_counter++ > AT91_ISR_PASS_LIMIT)
+ break;
+
+ status = UART_GET_CSR(port);
+ pending = status & port->read_status_mask;
+ } while (pending);
+ }
+ return IRQ_HANDLED;
+}
+
+/*
+ * 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);
+}
+
+/*
+ * Power / Clock management.
+ */
+static void at91_serial_pm(struct uart_port *port, unsigned int state, unsigned int oldstate)
+{
+ switch (state) {
+ case 0:
+ /*
+ * Enable the peripheral clock for this serial port.
+ * This is called on uart_open() or a resume event.
+ */
+ at91_sys_write(AT91_PMC_PCER, 1 << port->irq);
+ break;
+ case 3:
+ /*
+ * Disable the peripheral clock for this serial port.
+ * This is called on uart_close() or a suspend event.
+ */
+ if (port->irq != AT91_ID_SYS) /* is this a shared clock? */
+ at91_sys_write(AT91_PMC_PCDR, 1 << port->irq);
+ break;
+ default:
+ printk(KERN_ERR "at91_serial: unknown pm %d\n", state);
+ }
+}
+
+/*
+ * Change the port parameters
+ */
+static void at91_set_termios(struct uart_port *port, struct termios * termios, struct termios * old)
+{
+ unsigned long flags;
+ unsigned int mode, imr, quot, baud;
+
+ baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
+ quot = uart_get_divisor(port, baud);
+
+ /* Get current mode register */
+ mode = UART_GET_MR(port) & ~(AT91_US_CHRL | AT91_US_NBSTOP | AT91_US_PAR);
+
+ /* byte size */
+ switch (termios->c_cflag & CSIZE) {
+ case CS5:
+ mode |= AT91_US_CHRL_5;
+ break;
+ case CS6:
+ mode |= AT91_US_CHRL_6;
+ break;
+ case CS7:
+ mode |= AT91_US_CHRL_7;
+ break;
+ default:
+ mode |= AT91_US_CHRL_8;
+ break;
+ }
+
+ /* stop bits */
+ if (termios->c_cflag & CSTOPB)
+ mode |= AT91_US_NBSTOP_2;
+
+ /* parity */
+ if (termios->c_cflag & PARENB) {
+ if (termios->c_cflag & CMSPAR) { /* Mark or Space parity */
+ if (termios->c_cflag & PARODD)
+ mode |= AT91_US_PAR_MARK;
+ else
+ mode |= AT91_US_PAR_SPACE;
+ }
+ else if (termios->c_cflag & PARODD)
+ mode |= AT91_US_PAR_ODD;
+ else
+ mode |= AT91_US_PAR_EVEN;
+ }
+ else
+ mode |= AT91_US_PAR_NONE;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ port->read_status_mask |= AT91_US_OVRE;
+ if (termios->c_iflag & INPCK)
+ port->read_status_mask |= AT91_US_FRAME | AT91_US_PARE;
+ if (termios->c_iflag & (BRKINT | PARMRK))
+ port->read_status_mask |= AT91_US_RXBRK;
+
+ /*
+ * Characters to ignore
+ */
+ port->ignore_status_mask = 0;
+ if (termios->c_iflag & IGNPAR)
+ port->ignore_status_mask |= (AT91_US_FRAME | AT91_US_PARE);
+ if (termios->c_iflag & IGNBRK) {
+ port->ignore_status_mask |= AT91_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 |= AT91_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) & AT91_US_TXEMPTY)) { barrier(); }
+
+ /* disable receiver and transmitter */
+ UART_PUT_CR(port, AT91_US_TXDIS | AT91_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, AT91_US_RSTSTA | AT91_US_RSTRX);
+ UART_PUT_CR(port, AT91_US_TXEN | AT91_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);
+}
+
+/*
+ * Return string describing the specified port
+ */
+static const char *at91_type(struct uart_port *port)
+{
+ return (port->type == PORT_AT91RM9200) ? "AT91_SERIAL" : NULL;
+}
+
+/*
+ * Release the memory region(s) being used by 'port'.
+ */
+static void at91_release_port(struct uart_port *port)
+{
+ release_mem_region(port->mapbase,
+ (port->mapbase == AT91_VA_BASE_DBGU) ? 512 : SZ_16K);
+}
+
+/*
+ * Request the memory region(s) being used by 'port'.
+ */
+static int at91_request_port(struct uart_port *port)
+{
+ return request_mem_region(port->mapbase,
+ (port->mapbase == AT91_VA_BASE_DBGU) ? 512 : SZ_16K,
+ "at91_serial") != NULL ? 0 : -EBUSY;
+
+}
+
+/*
+ * Configure/autoconfigure the port.
+ */
+static void at91_config_port(struct uart_port *port, int flags)
+{
+ if (flags & UART_CONFIG_TYPE) {
+ port->type = PORT_AT91RM9200;
+ at91_request_port(port);
+ }
+}
+
+/*
+ * Verify the new serial_struct (for TIOCSSERIAL).
+ */
+static int at91_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+ int ret = 0;
+ if (ser->type != PORT_UNKNOWN && ser->type != PORT_AT91RM9200)
+ ret = -EINVAL;
+ if (port->irq != ser->irq)
+ ret = -EINVAL;
+ if (ser->io_type != SERIAL_IO_MEM)
+ ret = -EINVAL;
+ if (port->uartclk / 16 != ser->baud_base)
+ ret = -EINVAL;
+ if ((void *)port->mapbase != ser->iomem_base)
+ ret = -EINVAL;
+ if (port->iobase != ser->port)
+ ret = -EINVAL;
+ if (ser->hub6 != 0)
+ ret = -EINVAL;
+ return ret;
+}
+
+static struct uart_ops at91_pops = {
+ .tx_empty = at91_tx_empty,
+ .set_mctrl = at91_set_mctrl,
+ .get_mctrl = at91_get_mctrl,
+ .stop_tx = at91_stop_tx,
+ .start_tx = at91_start_tx,
+ .stop_rx = at91_stop_rx,
+ .enable_ms = at91_enable_ms,
+ .break_ctl = at91_break_ctl,
+ .startup = at91_startup,
+ .shutdown = at91_shutdown,
+ .set_termios = at91_set_termios,
+ .type = at91_type,
+ .release_port = at91_release_port,
+ .request_port = at91_request_port,
+ .config_port = at91_config_port,
+ .verify_port = at91_verify_port,
+ .pm = at91_serial_pm,
+};
+
+static struct uart_port at91_ports[AT91_NR_UART];
+
+void __init at91_init_ports(void)
+{
+ static int first = 1;
+ int i;
+
+ if (!first)
+ return;
+ first = 0;
+
+ for (i = 0; i < AT91_NR_UART; i++) {
+ at91_ports[i].iotype = UPIO_MEM;
+ at91_ports[i].flags = UPF_BOOT_AUTOCONF;
+ at91_ports[i].uartclk = at91_master_clock;
+ at91_ports[i].ops = &at91_pops;
+ at91_ports[i].fifosize = 1;
+ at91_ports[i].line = i;
+ }
+}
+
+void __init at91_register_uart_fns(struct at91rm9200_port_fns *fns)
+{
+ if (fns->enable_ms)
+ at91_pops.enable_ms = fns->enable_ms;
+ if (fns->get_mctrl)
+ at91_pops.get_mctrl = fns->get_mctrl;
+ if (fns->set_mctrl)
+ at91_pops.set_mctrl = fns->set_mctrl;
+ at91_open = fns->open;
+ at91_close = fns->close;
+ at91_pops.pm = fns->pm;
+ at91_pops.set_wake = fns->set_wake;
+}
+
+/*
+ * Setup ports.
+ */
+void __init at91_register_uart(int idx, int port)
+{
+ if ((idx < 0) || (idx >= AT91_NR_UART)) {
+ printk(KERN_ERR "%s: bad index number %d\n", __FUNCTION__, idx);
+ return;
+ }
+
+ switch (port) {
+ case 0:
+ at91_ports[idx].membase = (void __iomem *) AT91_VA_BASE_US0;
+ at91_ports[idx].mapbase = AT91_VA_BASE_US0;
+ at91_ports[idx].irq = AT91_ID_US0;
+ AT91_CfgPIO_USART0();
+ break;
+ case 1:
+ at91_ports[idx].membase = (void __iomem *) AT91_VA_BASE_US1;
+ at91_ports[idx].mapbase = AT91_VA_BASE_US1;
+ at91_ports[idx].irq = AT91_ID_US1;
+ AT91_CfgPIO_USART1();
+ break;
+ case 2:
+ at91_ports[idx].membase = (void __iomem *) AT91_VA_BASE_US2;
+ at91_ports[idx].mapbase = AT91_VA_BASE_US2;
+ at91_ports[idx].irq = AT91_ID_US2;
+ AT91_CfgPIO_USART2();
+ break;
+ case 3:
+ at91_ports[idx].membase = (void __iomem *) AT91_VA_BASE_US3;
+ at91_ports[idx].mapbase = AT91_VA_BASE_US3;
+ at91_ports[idx].irq = AT91_ID_US3;
+ AT91_CfgPIO_USART3();
+ break;
+ case 4:
+ at91_ports[idx].membase = (void __iomem *) AT91_VA_BASE_DBGU;
+ at91_ports[idx].mapbase = AT91_VA_BASE_DBGU;
+ at91_ports[idx].irq = AT91_ID_SYS;
+ AT91_CfgPIO_DBGU();
+ break;
+ default:
+ printk(KERN_ERR "%s : bad port number %d\n", __FUNCTION__, port);
+ }
+}
+
+#ifdef CONFIG_SERIAL_AT91_CONSOLE
+
+/*
+ * 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 */
+}
+
+/*
+ * If the port was already initialised (eg, by a boot loader), try to determine
+ * the current setup.
+ */
+static void __init at91_console_get_options(struct uart_port *port, int *baud, int *parity, int *bits)
+{
+ unsigned int mr, quot;
+
+// TODO: CR is a write-only register
+// unsigned int cr;
+//
+// cr = UART_GET_CR(port) & (AT91_US_RXEN | AT91_US_TXEN);
+// if (cr == (AT91_US_RXEN | AT91_US_TXEN)) {
+// /* ok, the port was enabled */
+// }
+
+ mr = UART_GET_MR(port) & AT91_US_CHRL;
+ if (mr == AT91_US_CHRL_8)
+ *bits = 8;
+ else
+ *bits = 7;
+
+ mr = UART_GET_MR(port) & AT91_US_PAR;
+ if (mr == AT91_US_PAR_EVEN)
+ *parity = 'e';
+ else if (mr == AT91_US_PAR_ODD)
+ *parity = 'o';
+
+ quot = UART_GET_BRGR(port);
+ *baud = port->uartclk / (16 * (quot));
+}
+
+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);
+}
+
+static struct uart_driver at91_uart;
+
+static struct console at91_console = {
+ .name = AT91_DEVICENAME,
+ .write = at91_console_write,
+ .device = uart_console_device,
+ .setup = at91_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &at91_uart,
+};
+
+#define AT91_CONSOLE_DEVICE &at91_console
+
+static int __init at91_console_init(void)
+{
+ at91_init_ports();
+
+ at91_console.index = at91_console_port;
+ register_console(&at91_console);
+ return 0;
+}
+console_initcall(at91_console_init);
+
+#else
+#define AT91_CONSOLE_DEVICE NULL
+#endif
+
+static struct uart_driver at91_uart = {
+ .owner = THIS_MODULE,
+ .driver_name = AT91_DEVICENAME,
+ .dev_name = AT91_DEVICENAME,
+ .devfs_name = AT91_DEVICENAME,
+ .major = SERIAL_AT91_MAJOR,
+ .minor = MINOR_START,
+ .nr = AT91_NR_UART,
+ .cons = AT91_CONSOLE_DEVICE,
+};
+
+static int __init at91_serial_init(void)
+{
+ int ret, i;
+
+ at91_init_ports();
+
+ ret = uart_register_driver(&at91_uart);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < AT91_NR_UART; i++) {
+ if (at91_serial_map[i] >= 0)
+ uart_add_one_port(&at91_uart, &at91_ports[i]);
+ }
+
+ return 0;
+}
+
+static void __exit at91_serial_exit(void)
+{
+ int i;
+
+ for (i = 0; i < AT91_NR_UART; i++) {
+ if (at91_serial_map[i] >= 0)
+ uart_remove_one_port(&at91_uart, &at91_ports[i]);
+ }
+
+ uart_unregister_driver(&at91_uart);
+}
+
+module_init(at91_serial_init);
+module_exit(at91_serial_exit);
+
+MODULE_AUTHOR("Rick Bronson");
+MODULE_DESCRIPTION("AT91 generic serial port driver");
+MODULE_LICENSE("GPL");