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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/serial/mpc52xx_uart.c
downloadtalos-obmc-linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
talos-obmc-linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/serial/mpc52xx_uart.c')
-rw-r--r--drivers/serial/mpc52xx_uart.c852
1 files changed, 852 insertions, 0 deletions
diff --git a/drivers/serial/mpc52xx_uart.c b/drivers/serial/mpc52xx_uart.c
new file mode 100644
index 000000000000..2a5cf174ca30
--- /dev/null
+++ b/drivers/serial/mpc52xx_uart.c
@@ -0,0 +1,852 @@
+/*
+ * drivers/serial/mpc52xx_uart.c
+ *
+ * Driver for the PSC of the Freescale MPC52xx PSCs configured as UARTs.
+ *
+ * FIXME According to the usermanual the status bits in the status register
+ * are only updated when the peripherals access the FIFO and not when the
+ * CPU access them. So since we use this bits to know when we stop writing
+ * and reading, they may not be updated in-time and a race condition may
+ * exists. But I haven't be able to prove this and I don't care. But if
+ * any problem arises, it might worth checking. The TX/RX FIFO Stats
+ * registers should be used in addition.
+ * Update: Actually, they seem updated ... At least the bits we use.
+ *
+ *
+ * Maintainer : Sylvain Munaut <tnt@246tNt.com>
+ *
+ * Some of the code has been inspired/copied from the 2.4 code written
+ * by Dale Farnsworth <dfarnsworth@mvista.com>.
+ *
+ * Copyright (C) 2004-2005 Sylvain Munaut <tnt@246tNt.com>
+ * Copyright (C) 2003 MontaVista, Software, Inc.
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+/* Platform device Usage :
+ *
+ * Since PSCs can have multiple function, the correct driver for each one
+ * is selected by calling mpc52xx_match_psc_function(...). The function
+ * handled by this driver is "uart".
+ *
+ * The driver init all necessary registers to place the PSC in uart mode without
+ * DCD. However, the pin multiplexing aren't changed and should be set either
+ * by the bootloader or in the platform init code.
+ *
+ * The idx field must be equal to the PSC index ( e.g. 0 for PSC1, 1 for PSC2,
+ * and so on). So the PSC1 is mapped to /dev/ttyS0, PSC2 to /dev/ttyS1 and so
+ * on. But be warned, it's an ABSOLUTE REQUIREMENT ! This is needed mainly for
+ * the console code : without this 1:1 mapping, at early boot time, when we are
+ * parsing the kernel args console=ttyS?, we wouldn't know wich PSC it will be
+ * mapped to.
+ */
+
+#include <linux/config.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/tty.h>
+#include <linux/serial.h>
+#include <linux/sysrq.h>
+#include <linux/console.h>
+
+#include <asm/delay.h>
+#include <asm/io.h>
+
+#include <asm/mpc52xx.h>
+#include <asm/mpc52xx_psc.h>
+
+#if defined(CONFIG_SERIAL_MPC52xx_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/serial_core.h>
+
+
+
+#define ISR_PASS_LIMIT 256 /* Max number of iteration in the interrupt */
+
+
+static struct uart_port mpc52xx_uart_ports[MPC52xx_PSC_MAXNUM];
+ /* Rem: - We use the read_status_mask as a shadow of
+ * psc->mpc52xx_psc_imr
+ * - It's important that is array is all zero on start as we
+ * use it to know if it's initialized or not ! If it's not sure
+ * it's cleared, then a memset(...,0,...) should be added to
+ * the console_init
+ */
+
+#define PSC(port) ((struct mpc52xx_psc __iomem *)((port)->membase))
+
+
+/* Forward declaration of the interruption handling routine */
+static irqreturn_t mpc52xx_uart_int(int irq,void *dev_id,struct pt_regs *regs);
+
+
+/* Simple macro to test if a port is console or not. This one is taken
+ * for serial_core.c and maybe should be moved to serial_core.h ? */
+#ifdef CONFIG_SERIAL_CORE_CONSOLE
+#define uart_console(port) ((port)->cons && (port)->cons->index == (port)->line)
+#else
+#define uart_console(port) (0)
+#endif
+
+
+/* ======================================================================== */
+/* UART operations */
+/* ======================================================================== */
+
+static unsigned int
+mpc52xx_uart_tx_empty(struct uart_port *port)
+{
+ int status = in_be16(&PSC(port)->mpc52xx_psc_status);
+ return (status & MPC52xx_PSC_SR_TXEMP) ? TIOCSER_TEMT : 0;
+}
+
+static void
+mpc52xx_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+ /* Not implemented */
+}
+
+static unsigned int
+mpc52xx_uart_get_mctrl(struct uart_port *port)
+{
+ /* Not implemented */
+ return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
+}
+
+static void
+mpc52xx_uart_stop_tx(struct uart_port *port, unsigned int tty_stop)
+{
+ /* port->lock taken by caller */
+ port->read_status_mask &= ~MPC52xx_PSC_IMR_TXRDY;
+ out_be16(&PSC(port)->mpc52xx_psc_imr,port->read_status_mask);
+}
+
+static void
+mpc52xx_uart_start_tx(struct uart_port *port, unsigned int tty_start)
+{
+ /* port->lock taken by caller */
+ port->read_status_mask |= MPC52xx_PSC_IMR_TXRDY;
+ out_be16(&PSC(port)->mpc52xx_psc_imr,port->read_status_mask);
+}
+
+static void
+mpc52xx_uart_send_xchar(struct uart_port *port, char ch)
+{
+ unsigned long flags;
+ spin_lock_irqsave(&port->lock, flags);
+
+ port->x_char = ch;
+ if (ch) {
+ /* Make sure tx interrupts are on */
+ /* Truly necessary ??? They should be anyway */
+ port->read_status_mask |= MPC52xx_PSC_IMR_TXRDY;
+ out_be16(&PSC(port)->mpc52xx_psc_imr,port->read_status_mask);
+ }
+
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void
+mpc52xx_uart_stop_rx(struct uart_port *port)
+{
+ /* port->lock taken by caller */
+ port->read_status_mask &= ~MPC52xx_PSC_IMR_RXRDY;
+ out_be16(&PSC(port)->mpc52xx_psc_imr,port->read_status_mask);
+}
+
+static void
+mpc52xx_uart_enable_ms(struct uart_port *port)
+{
+ /* Not implemented */
+}
+
+static void
+mpc52xx_uart_break_ctl(struct uart_port *port, int ctl)
+{
+ unsigned long flags;
+ spin_lock_irqsave(&port->lock, flags);
+
+ if ( ctl == -1 )
+ out_8(&PSC(port)->command,MPC52xx_PSC_START_BRK);
+ else
+ out_8(&PSC(port)->command,MPC52xx_PSC_STOP_BRK);
+
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static int
+mpc52xx_uart_startup(struct uart_port *port)
+{
+ struct mpc52xx_psc __iomem *psc = PSC(port);
+ int ret;
+
+ /* Request IRQ */
+ ret = request_irq(port->irq, mpc52xx_uart_int,
+ SA_INTERRUPT | SA_SAMPLE_RANDOM, "mpc52xx_psc_uart", port);
+ if (ret)
+ return ret;
+
+ /* Reset/activate the port, clear and enable interrupts */
+ out_8(&psc->command,MPC52xx_PSC_RST_RX);
+ out_8(&psc->command,MPC52xx_PSC_RST_TX);
+
+ out_be32(&psc->sicr,0); /* UART mode DCD ignored */
+
+ out_be16(&psc->mpc52xx_psc_clock_select, 0xdd00); /* /16 prescaler on */
+
+ out_8(&psc->rfcntl, 0x00);
+ out_be16(&psc->rfalarm, 0x1ff);
+ out_8(&psc->tfcntl, 0x07);
+ out_be16(&psc->tfalarm, 0x80);
+
+ port->read_status_mask |= MPC52xx_PSC_IMR_RXRDY | MPC52xx_PSC_IMR_TXRDY;
+ out_be16(&psc->mpc52xx_psc_imr,port->read_status_mask);
+
+ out_8(&psc->command,MPC52xx_PSC_TX_ENABLE);
+ out_8(&psc->command,MPC52xx_PSC_RX_ENABLE);
+
+ return 0;
+}
+
+static void
+mpc52xx_uart_shutdown(struct uart_port *port)
+{
+ struct mpc52xx_psc __iomem *psc = PSC(port);
+
+ /* Shut down the port, interrupt and all */
+ out_8(&psc->command,MPC52xx_PSC_RST_RX);
+ out_8(&psc->command,MPC52xx_PSC_RST_TX);
+
+ port->read_status_mask = 0;
+ out_be16(&psc->mpc52xx_psc_imr,port->read_status_mask);
+
+ /* Release interrupt */
+ free_irq(port->irq, port);
+}
+
+static void
+mpc52xx_uart_set_termios(struct uart_port *port, struct termios *new,
+ struct termios *old)
+{
+ struct mpc52xx_psc __iomem *psc = PSC(port);
+ unsigned long flags;
+ unsigned char mr1, mr2;
+ unsigned short ctr;
+ unsigned int j, baud, quot;
+
+ /* Prepare what we're gonna write */
+ mr1 = 0;
+
+ switch (new->c_cflag & CSIZE) {
+ case CS5: mr1 |= MPC52xx_PSC_MODE_5_BITS;
+ break;
+ case CS6: mr1 |= MPC52xx_PSC_MODE_6_BITS;
+ break;
+ case CS7: mr1 |= MPC52xx_PSC_MODE_7_BITS;
+ break;
+ case CS8:
+ default: mr1 |= MPC52xx_PSC_MODE_8_BITS;
+ }
+
+ if (new->c_cflag & PARENB) {
+ mr1 |= (new->c_cflag & PARODD) ?
+ MPC52xx_PSC_MODE_PARODD : MPC52xx_PSC_MODE_PAREVEN;
+ } else
+ mr1 |= MPC52xx_PSC_MODE_PARNONE;
+
+
+ mr2 = 0;
+
+ if (new->c_cflag & CSTOPB)
+ mr2 |= MPC52xx_PSC_MODE_TWO_STOP;
+ else
+ mr2 |= ((new->c_cflag & CSIZE) == CS5) ?
+ MPC52xx_PSC_MODE_ONE_STOP_5_BITS :
+ MPC52xx_PSC_MODE_ONE_STOP;
+
+
+ baud = uart_get_baud_rate(port, new, old, 0, port->uartclk/16);
+ quot = uart_get_divisor(port, baud);
+ ctr = quot & 0xffff;
+
+ /* Get the lock */
+ spin_lock_irqsave(&port->lock, flags);
+
+ /* Update the per-port timeout */
+ uart_update_timeout(port, new->c_cflag, baud);
+
+ /* Do our best to flush TX & RX, so we don't loose anything */
+ /* But we don't wait indefinitly ! */
+ j = 5000000; /* Maximum wait */
+ /* FIXME Can't receive chars since set_termios might be called at early
+ * boot for the console, all stuff is not yet ready to receive at that
+ * time and that just makes the kernel oops */
+ /* while (j-- && mpc52xx_uart_int_rx_chars(port)); */
+ while (!(in_be16(&psc->mpc52xx_psc_status) & MPC52xx_PSC_SR_TXEMP) &&
+ --j)
+ udelay(1);
+
+ if (!j)
+ printk( KERN_ERR "mpc52xx_uart.c: "
+ "Unable to flush RX & TX fifos in-time in set_termios."
+ "Some chars may have been lost.\n" );
+
+ /* Reset the TX & RX */
+ out_8(&psc->command,MPC52xx_PSC_RST_RX);
+ out_8(&psc->command,MPC52xx_PSC_RST_TX);
+
+ /* Send new mode settings */
+ out_8(&psc->command,MPC52xx_PSC_SEL_MODE_REG_1);
+ out_8(&psc->mode,mr1);
+ out_8(&psc->mode,mr2);
+ out_8(&psc->ctur,ctr >> 8);
+ out_8(&psc->ctlr,ctr & 0xff);
+
+ /* Reenable TX & RX */
+ out_8(&psc->command,MPC52xx_PSC_TX_ENABLE);
+ out_8(&psc->command,MPC52xx_PSC_RX_ENABLE);
+
+ /* We're all set, release the lock */
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static const char *
+mpc52xx_uart_type(struct uart_port *port)
+{
+ return port->type == PORT_MPC52xx ? "MPC52xx PSC" : NULL;
+}
+
+static void
+mpc52xx_uart_release_port(struct uart_port *port)
+{
+ if (port->flags & UPF_IOREMAP) { /* remapped by us ? */
+ iounmap(port->membase);
+ port->membase = NULL;
+ }
+
+ release_mem_region(port->mapbase, MPC52xx_PSC_SIZE);
+}
+
+static int
+mpc52xx_uart_request_port(struct uart_port *port)
+{
+ if (port->flags & UPF_IOREMAP) /* Need to remap ? */
+ port->membase = ioremap(port->mapbase, MPC52xx_PSC_SIZE);
+
+ if (!port->membase)
+ return -EINVAL;
+
+ return request_mem_region(port->mapbase, MPC52xx_PSC_SIZE,
+ "mpc52xx_psc_uart") != NULL ? 0 : -EBUSY;
+}
+
+static void
+mpc52xx_uart_config_port(struct uart_port *port, int flags)
+{
+ if ( (flags & UART_CONFIG_TYPE) &&
+ (mpc52xx_uart_request_port(port) == 0) )
+ port->type = PORT_MPC52xx;
+}
+
+static int
+mpc52xx_uart_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+ if ( ser->type != PORT_UNKNOWN && ser->type != PORT_MPC52xx )
+ return -EINVAL;
+
+ if ( (ser->irq != port->irq) ||
+ (ser->io_type != SERIAL_IO_MEM) ||
+ (ser->baud_base != port->uartclk) ||
+ (ser->iomem_base != (void*)port->mapbase) ||
+ (ser->hub6 != 0 ) )
+ return -EINVAL;
+
+ return 0;
+}
+
+
+static struct uart_ops mpc52xx_uart_ops = {
+ .tx_empty = mpc52xx_uart_tx_empty,
+ .set_mctrl = mpc52xx_uart_set_mctrl,
+ .get_mctrl = mpc52xx_uart_get_mctrl,
+ .stop_tx = mpc52xx_uart_stop_tx,
+ .start_tx = mpc52xx_uart_start_tx,
+ .send_xchar = mpc52xx_uart_send_xchar,
+ .stop_rx = mpc52xx_uart_stop_rx,
+ .enable_ms = mpc52xx_uart_enable_ms,
+ .break_ctl = mpc52xx_uart_break_ctl,
+ .startup = mpc52xx_uart_startup,
+ .shutdown = mpc52xx_uart_shutdown,
+ .set_termios = mpc52xx_uart_set_termios,
+/* .pm = mpc52xx_uart_pm, Not supported yet */
+/* .set_wake = mpc52xx_uart_set_wake, Not supported yet */
+ .type = mpc52xx_uart_type,
+ .release_port = mpc52xx_uart_release_port,
+ .request_port = mpc52xx_uart_request_port,
+ .config_port = mpc52xx_uart_config_port,
+ .verify_port = mpc52xx_uart_verify_port
+};
+
+
+/* ======================================================================== */
+/* Interrupt handling */
+/* ======================================================================== */
+
+static inline int
+mpc52xx_uart_int_rx_chars(struct uart_port *port, struct pt_regs *regs)
+{
+ struct tty_struct *tty = port->info->tty;
+ unsigned char ch;
+ unsigned short status;
+
+ /* While we can read, do so ! */
+ while ( (status = in_be16(&PSC(port)->mpc52xx_psc_status)) &
+ MPC52xx_PSC_SR_RXRDY) {
+
+ /* If we are full, just stop reading */
+ if (tty->flip.count >= TTY_FLIPBUF_SIZE)
+ break;
+
+ /* Get the char */
+ ch = in_8(&PSC(port)->mpc52xx_psc_buffer_8);
+
+ /* Handle sysreq char */
+#ifdef SUPPORT_SYSRQ
+ if (uart_handle_sysrq_char(port, ch, regs)) {
+ port->sysrq = 0;
+ continue;
+ }
+#endif
+
+ /* Store it */
+ *tty->flip.char_buf_ptr = ch;
+ *tty->flip.flag_buf_ptr = 0;
+ port->icount.rx++;
+
+ if ( status & (MPC52xx_PSC_SR_PE |
+ MPC52xx_PSC_SR_FE |
+ MPC52xx_PSC_SR_RB |
+ MPC52xx_PSC_SR_OE) ) {
+
+ if (status & MPC52xx_PSC_SR_RB) {
+ *tty->flip.flag_buf_ptr = TTY_BREAK;
+ uart_handle_break(port);
+ } else if (status & MPC52xx_PSC_SR_PE)
+ *tty->flip.flag_buf_ptr = TTY_PARITY;
+ else if (status & MPC52xx_PSC_SR_FE)
+ *tty->flip.flag_buf_ptr = TTY_FRAME;
+ if (status & MPC52xx_PSC_SR_OE) {
+ /*
+ * Overrun is special, since it's
+ * reported immediately, and doesn't
+ * affect the current character
+ */
+ if (tty->flip.count < (TTY_FLIPBUF_SIZE-1)) {
+ tty->flip.flag_buf_ptr++;
+ tty->flip.char_buf_ptr++;
+ tty->flip.count++;
+ }
+ *tty->flip.flag_buf_ptr = TTY_OVERRUN;
+ }
+
+ /* Clear error condition */
+ out_8(&PSC(port)->command,MPC52xx_PSC_RST_ERR_STAT);
+
+ }
+
+ tty->flip.char_buf_ptr++;
+ tty->flip.flag_buf_ptr++;
+ tty->flip.count++;
+
+ }
+
+ tty_flip_buffer_push(tty);
+
+ return in_be16(&PSC(port)->mpc52xx_psc_status) & MPC52xx_PSC_SR_RXRDY;
+}
+
+static inline int
+mpc52xx_uart_int_tx_chars(struct uart_port *port)
+{
+ struct circ_buf *xmit = &port->info->xmit;
+
+ /* Process out of band chars */
+ if (port->x_char) {
+ out_8(&PSC(port)->mpc52xx_psc_buffer_8, port->x_char);
+ port->icount.tx++;
+ port->x_char = 0;
+ return 1;
+ }
+
+ /* Nothing to do ? */
+ if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
+ mpc52xx_uart_stop_tx(port,0);
+ return 0;
+ }
+
+ /* Send chars */
+ while (in_be16(&PSC(port)->mpc52xx_psc_status) & MPC52xx_PSC_SR_TXRDY) {
+ out_8(&PSC(port)->mpc52xx_psc_buffer_8, xmit->buf[xmit->tail]);
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ port->icount.tx++;
+ if (uart_circ_empty(xmit))
+ break;
+ }
+
+ /* Wake up */
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(port);
+
+ /* Maybe we're done after all */
+ if (uart_circ_empty(xmit)) {
+ mpc52xx_uart_stop_tx(port,0);
+ return 0;
+ }
+
+ return 1;
+}
+
+static irqreturn_t
+mpc52xx_uart_int(int irq, void *dev_id, struct pt_regs *regs)
+{
+ struct uart_port *port = (struct uart_port *) dev_id;
+ unsigned long pass = ISR_PASS_LIMIT;
+ unsigned int keepgoing;
+ unsigned short status;
+
+ if ( irq != port->irq ) {
+ printk( KERN_WARNING
+ "mpc52xx_uart_int : " \
+ "Received wrong int %d. Waiting for %d\n",
+ irq, port->irq);
+ return IRQ_NONE;
+ }
+
+ spin_lock(&port->lock);
+
+ /* While we have stuff to do, we continue */
+ do {
+ /* If we don't find anything to do, we stop */
+ keepgoing = 0;
+
+ /* Read status */
+ status = in_be16(&PSC(port)->mpc52xx_psc_isr);
+ status &= port->read_status_mask;
+
+ /* Do we need to receive chars ? */
+ /* For this RX interrupts must be on and some chars waiting */
+ if ( status & MPC52xx_PSC_IMR_RXRDY )
+ keepgoing |= mpc52xx_uart_int_rx_chars(port, regs);
+
+ /* Do we need to send chars ? */
+ /* For this, TX must be ready and TX interrupt enabled */
+ if ( status & MPC52xx_PSC_IMR_TXRDY )
+ keepgoing |= mpc52xx_uart_int_tx_chars(port);
+
+ /* Limit number of iteration */
+ if ( !(--pass) )
+ keepgoing = 0;
+
+ } while (keepgoing);
+
+ spin_unlock(&port->lock);
+
+ return IRQ_HANDLED;
+}
+
+
+/* ======================================================================== */
+/* Console ( if applicable ) */
+/* ======================================================================== */
+
+#ifdef CONFIG_SERIAL_MPC52xx_CONSOLE
+
+static void __init
+mpc52xx_console_get_options(struct uart_port *port,
+ int *baud, int *parity, int *bits, int *flow)
+{
+ struct mpc52xx_psc __iomem *psc = PSC(port);
+ unsigned char mr1;
+
+ /* Read the mode registers */
+ out_8(&psc->command,MPC52xx_PSC_SEL_MODE_REG_1);
+ mr1 = in_8(&psc->mode);
+
+ /* CT{U,L}R are write-only ! */
+ *baud = __res.bi_baudrate ?
+ __res.bi_baudrate : CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
+
+ /* Parse them */
+ switch (mr1 & MPC52xx_PSC_MODE_BITS_MASK) {
+ case MPC52xx_PSC_MODE_5_BITS: *bits = 5; break;
+ case MPC52xx_PSC_MODE_6_BITS: *bits = 6; break;
+ case MPC52xx_PSC_MODE_7_BITS: *bits = 7; break;
+ case MPC52xx_PSC_MODE_8_BITS:
+ default: *bits = 8;
+ }
+
+ if (mr1 & MPC52xx_PSC_MODE_PARNONE)
+ *parity = 'n';
+ else
+ *parity = mr1 & MPC52xx_PSC_MODE_PARODD ? 'o' : 'e';
+}
+
+static void
+mpc52xx_console_write(struct console *co, const char *s, unsigned int count)
+{
+ struct uart_port *port = &mpc52xx_uart_ports[co->index];
+ struct mpc52xx_psc __iomem *psc = PSC(port);
+ unsigned int i, j;
+
+ /* Disable interrupts */
+ out_be16(&psc->mpc52xx_psc_imr, 0);
+
+ /* Wait the TX buffer to be empty */
+ j = 5000000; /* Maximum wait */
+ while (!(in_be16(&psc->mpc52xx_psc_status) & MPC52xx_PSC_SR_TXEMP) &&
+ --j)
+ udelay(1);
+
+ /* Write all the chars */
+ for ( i=0 ; i<count ; i++ ) {
+
+ /* Send the char */
+ out_8(&psc->mpc52xx_psc_buffer_8, *s);
+
+ /* Line return handling */
+ if ( *s++ == '\n' )
+ out_8(&psc->mpc52xx_psc_buffer_8, '\r');
+
+ /* Wait the TX buffer to be empty */
+ j = 20000; /* Maximum wait */
+ while (!(in_be16(&psc->mpc52xx_psc_status) &
+ MPC52xx_PSC_SR_TXEMP) && --j)
+ udelay(1);
+ }
+
+ /* Restore interrupt state */
+ out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
+}
+
+static int __init
+mpc52xx_console_setup(struct console *co, char *options)
+{
+ struct uart_port *port = &mpc52xx_uart_ports[co->index];
+
+ int baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+
+ if (co->index < 0 || co->index >= MPC52xx_PSC_MAXNUM)
+ return -EINVAL;
+
+ /* Basic port init. Needed since we use some uart_??? func before
+ * real init for early access */
+ spin_lock_init(&port->lock);
+ port->uartclk = __res.bi_ipbfreq / 2; /* Look at CTLR doc */
+ port->ops = &mpc52xx_uart_ops;
+ port->mapbase = MPC52xx_PA(MPC52xx_PSCx_OFFSET(co->index+1));
+
+ /* We ioremap ourself */
+ port->membase = ioremap(port->mapbase, MPC52xx_PSC_SIZE);
+ if (port->membase == NULL)
+ return -EINVAL;
+
+ /* Setup the port parameters accoding to options */
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+ else
+ mpc52xx_console_get_options(port, &baud, &parity, &bits, &flow);
+
+ return uart_set_options(port, co, baud, parity, bits, flow);
+}
+
+
+extern struct uart_driver mpc52xx_uart_driver;
+
+static struct console mpc52xx_console = {
+ .name = "ttyS",
+ .write = mpc52xx_console_write,
+ .device = uart_console_device,
+ .setup = mpc52xx_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1, /* Specified on the cmdline (e.g. console=ttyS0 ) */
+ .data = &mpc52xx_uart_driver,
+};
+
+
+static int __init
+mpc52xx_console_init(void)
+{
+ register_console(&mpc52xx_console);
+ return 0;
+}
+
+console_initcall(mpc52xx_console_init);
+
+#define MPC52xx_PSC_CONSOLE &mpc52xx_console
+#else
+#define MPC52xx_PSC_CONSOLE NULL
+#endif
+
+
+/* ======================================================================== */
+/* UART Driver */
+/* ======================================================================== */
+
+static struct uart_driver mpc52xx_uart_driver = {
+ .owner = THIS_MODULE,
+ .driver_name = "mpc52xx_psc_uart",
+ .dev_name = "ttyS",
+ .devfs_name = "ttyS",
+ .major = TTY_MAJOR,
+ .minor = 64,
+ .nr = MPC52xx_PSC_MAXNUM,
+ .cons = MPC52xx_PSC_CONSOLE,
+};
+
+
+/* ======================================================================== */
+/* Platform Driver */
+/* ======================================================================== */
+
+static int __devinit
+mpc52xx_uart_probe(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct resource *res = pdev->resource;
+
+ struct uart_port *port = NULL;
+ int i, idx, ret;
+
+ /* Check validity & presence */
+ idx = pdev->id;
+ if (idx < 0 || idx >= MPC52xx_PSC_MAXNUM)
+ return -EINVAL;
+
+ if (!mpc52xx_match_psc_function(idx,"uart"))
+ return -ENODEV;
+
+ /* Init the port structure */
+ port = &mpc52xx_uart_ports[idx];
+
+ memset(port, 0x00, sizeof(struct uart_port));
+
+ spin_lock_init(&port->lock);
+ port->uartclk = __res.bi_ipbfreq / 2; /* Look at CTLR doc */
+ port->fifosize = 255; /* Should be 512 ! But it can't be */
+ /* stored in a unsigned char */
+ port->iotype = UPIO_MEM;
+ port->flags = UPF_BOOT_AUTOCONF |
+ ( uart_console(port) ? 0 : UPF_IOREMAP );
+ port->line = idx;
+ port->ops = &mpc52xx_uart_ops;
+
+ /* Search for IRQ and mapbase */
+ for (i=0 ; i<pdev->num_resources ; i++, res++) {
+ if (res->flags & IORESOURCE_MEM)
+ port->mapbase = res->start;
+ else if (res->flags & IORESOURCE_IRQ)
+ port->irq = res->start;
+ }
+ if (!port->irq || !port->mapbase)
+ return -EINVAL;
+
+ /* Add the port to the uart sub-system */
+ ret = uart_add_one_port(&mpc52xx_uart_driver, port);
+ if (!ret)
+ dev_set_drvdata(dev, (void*)port);
+
+ return ret;
+}
+
+static int
+mpc52xx_uart_remove(struct device *dev)
+{
+ struct uart_port *port = (struct uart_port *) dev_get_drvdata(dev);
+
+ dev_set_drvdata(dev, NULL);
+
+ if (port)
+ uart_remove_one_port(&mpc52xx_uart_driver, port);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int
+mpc52xx_uart_suspend(struct device *dev, u32 state, u32 level)
+{
+ struct uart_port *port = (struct uart_port *) dev_get_drvdata(dev);
+
+ if (sport && level == SUSPEND_DISABLE)
+ uart_suspend_port(&mpc52xx_uart_driver, port);
+
+ return 0;
+}
+
+static int
+mpc52xx_uart_resume(struct device *dev, u32 level)
+{
+ struct uart_port *port = (struct uart_port *) dev_get_drvdata(dev);
+
+ if (port && level == RESUME_ENABLE)
+ uart_resume_port(&mpc52xx_uart_driver, port);
+
+ return 0;
+}
+#endif
+
+static struct device_driver mpc52xx_uart_platform_driver = {
+ .name = "mpc52xx-psc",
+ .bus = &platform_bus_type,
+ .probe = mpc52xx_uart_probe,
+ .remove = mpc52xx_uart_remove,
+#ifdef CONFIG_PM
+ .suspend = mpc52xx_uart_suspend,
+ .resume = mpc52xx_uart_resume,
+#endif
+};
+
+
+/* ======================================================================== */
+/* Module */
+/* ======================================================================== */
+
+static int __init
+mpc52xx_uart_init(void)
+{
+ int ret;
+
+ printk(KERN_INFO "Serial: MPC52xx PSC driver\n");
+
+ ret = uart_register_driver(&mpc52xx_uart_driver);
+ if (ret == 0) {
+ ret = driver_register(&mpc52xx_uart_platform_driver);
+ if (ret)
+ uart_unregister_driver(&mpc52xx_uart_driver);
+ }
+
+ return ret;
+}
+
+static void __exit
+mpc52xx_uart_exit(void)
+{
+ driver_unregister(&mpc52xx_uart_platform_driver);
+ uart_unregister_driver(&mpc52xx_uart_driver);
+}
+
+
+module_init(mpc52xx_uart_init);
+module_exit(mpc52xx_uart_exit);
+
+MODULE_AUTHOR("Sylvain Munaut <tnt@246tNt.com>");
+MODULE_DESCRIPTION("Freescale MPC52xx PSC UART");
+MODULE_LICENSE("GPL");
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