| /* |
| * Driver core for serial ports |
| * |
| * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o. |
| * |
| * Copyright 1999 ARM Limited |
| * Copyright (C) 2000-2001 Deep Blue Solutions Ltd. |
| * |
| * 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/module.h> |
| #include <linux/tty.h> |
| #include <linux/slab.h> |
| #include <linux/init.h> |
| #include <linux/console.h> |
| #include <linux/proc_fs.h> |
| #include <linux/seq_file.h> |
| #include <linux/device.h> |
| #include <linux/serial.h> /* for serial_state and serial_icounter_struct */ |
| #include <linux/serial_core.h> |
| #include <linux/delay.h> |
| #include <linux/mutex.h> |
| |
| #include <asm/irq.h> |
| #include <asm/uaccess.h> |
| |
| /* |
| * This is used to lock changes in serial line configuration. |
| */ |
| static DEFINE_MUTEX(port_mutex); |
| |
| /* |
| * lockdep: port->lock is initialized in two places, but we |
| * want only one lock-class: |
| */ |
| static struct lock_class_key port_lock_key; |
| |
| #define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8) |
| |
| #ifdef CONFIG_SERIAL_CORE_CONSOLE |
| #define uart_console(port) ((port)->cons && (port)->cons->index == (port)->line) |
| #else |
| #define uart_console(port) (0) |
| #endif |
| |
| static void uart_change_speed(struct tty_struct *tty, struct uart_state *state, |
| struct ktermios *old_termios); |
| static void __uart_wait_until_sent(struct uart_port *port, int timeout); |
| static void uart_change_pm(struct uart_state *state, int pm_state); |
| |
| /* |
| * This routine is used by the interrupt handler to schedule processing in |
| * the software interrupt portion of the driver. |
| */ |
| void uart_write_wakeup(struct uart_port *port) |
| { |
| struct uart_state *state = port->state; |
| /* |
| * This means you called this function _after_ the port was |
| * closed. No cookie for you. |
| */ |
| BUG_ON(!state); |
| tasklet_schedule(&state->tlet); |
| } |
| |
| static void uart_stop(struct tty_struct *tty) |
| { |
| struct uart_state *state = tty->driver_data; |
| struct uart_port *port = state->uart_port; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&port->lock, flags); |
| port->ops->stop_tx(port); |
| spin_unlock_irqrestore(&port->lock, flags); |
| } |
| |
| static void __uart_start(struct tty_struct *tty) |
| { |
| struct uart_state *state = tty->driver_data; |
| struct uart_port *port = state->uart_port; |
| |
| if (!uart_circ_empty(&state->xmit) && state->xmit.buf && |
| !tty->stopped && !tty->hw_stopped) |
| port->ops->start_tx(port); |
| } |
| |
| static void uart_start(struct tty_struct *tty) |
| { |
| struct uart_state *state = tty->driver_data; |
| struct uart_port *port = state->uart_port; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&port->lock, flags); |
| __uart_start(tty); |
| spin_unlock_irqrestore(&port->lock, flags); |
| } |
| |
| static void uart_tasklet_action(unsigned long data) |
| { |
| struct uart_state *state = (struct uart_state *)data; |
| tty_wakeup(state->port.tty); |
| } |
| |
| static inline void |
| uart_update_mctrl(struct uart_port *port, unsigned int set, unsigned int clear) |
| { |
| unsigned long flags; |
| unsigned int old; |
| |
| spin_lock_irqsave(&port->lock, flags); |
| old = port->mctrl; |
| port->mctrl = (old & ~clear) | set; |
| if (old != port->mctrl) |
| port->ops->set_mctrl(port, port->mctrl); |
| spin_unlock_irqrestore(&port->lock, flags); |
| } |
| |
| #define uart_set_mctrl(port, set) uart_update_mctrl(port, set, 0) |
| #define uart_clear_mctrl(port, clear) uart_update_mctrl(port, 0, clear) |
| |
| /* |
| * Startup the port. This will be called once per open. All calls |
| * will be serialised by the per-port mutex. |
| */ |
| static int uart_startup(struct tty_struct *tty, struct uart_state *state, int init_hw) |
| { |
| struct uart_port *uport = state->uart_port; |
| struct tty_port *port = &state->port; |
| unsigned long page; |
| int retval = 0; |
| |
| if (port->flags & ASYNC_INITIALIZED) |
| return 0; |
| |
| /* |
| * Set the TTY IO error marker - we will only clear this |
| * once we have successfully opened the port. Also set |
| * up the tty->alt_speed kludge |
| */ |
| set_bit(TTY_IO_ERROR, &tty->flags); |
| |
| if (uport->type == PORT_UNKNOWN) |
| return 0; |
| |
| /* |
| * Initialise and allocate the transmit and temporary |
| * buffer. |
| */ |
| if (!state->xmit.buf) { |
| /* This is protected by the per port mutex */ |
| page = get_zeroed_page(GFP_KERNEL); |
| if (!page) |
| return -ENOMEM; |
| |
| state->xmit.buf = (unsigned char *) page; |
| uart_circ_clear(&state->xmit); |
| } |
| |
| retval = uport->ops->startup(uport); |
| if (retval == 0) { |
| if (uart_console(uport) && uport->cons->cflag) { |
| tty->termios->c_cflag = uport->cons->cflag; |
| uport->cons->cflag = 0; |
| } |
| /* |
| * Initialise the hardware port settings. |
| */ |
| uart_change_speed(tty, state, NULL); |
| |
| if (init_hw) { |
| /* |
| * Setup the RTS and DTR signals once the |
| * port is open and ready to respond. |
| */ |
| if (tty->termios->c_cflag & CBAUD) |
| uart_set_mctrl(uport, TIOCM_RTS | TIOCM_DTR); |
| } |
| |
| if (port->flags & ASYNC_CTS_FLOW) { |
| spin_lock_irq(&uport->lock); |
| if (!(uport->ops->get_mctrl(uport) & TIOCM_CTS)) |
| tty->hw_stopped = 1; |
| spin_unlock_irq(&uport->lock); |
| } |
| |
| set_bit(ASYNCB_INITIALIZED, &port->flags); |
| |
| clear_bit(TTY_IO_ERROR, &tty->flags); |
| } |
| |
| if (retval && capable(CAP_SYS_ADMIN)) |
| retval = 0; |
| |
| return retval; |
| } |
| |
| /* |
| * This routine will shutdown a serial port; interrupts are disabled, and |
| * DTR is dropped if the hangup on close termio flag is on. Calls to |
| * uart_shutdown are serialised by the per-port semaphore. |
| */ |
| static void uart_shutdown(struct tty_struct *tty, struct uart_state *state) |
| { |
| struct uart_port *uport = state->uart_port; |
| struct tty_port *port = &state->port; |
| |
| /* |
| * Set the TTY IO error marker |
| */ |
| if (tty) |
| set_bit(TTY_IO_ERROR, &tty->flags); |
| |
| if (test_and_clear_bit(ASYNCB_INITIALIZED, &port->flags)) { |
| /* |
| * Turn off DTR and RTS early. |
| */ |
| if (!tty || (tty->termios->c_cflag & HUPCL)) |
| uart_clear_mctrl(uport, TIOCM_DTR | TIOCM_RTS); |
| |
| /* |
| * clear delta_msr_wait queue to avoid mem leaks: we may free |
| * the irq here so the queue might never be woken up. Note |
| * that we won't end up waiting on delta_msr_wait again since |
| * any outstanding file descriptors should be pointing at |
| * hung_up_tty_fops now. |
| */ |
| wake_up_interruptible(&port->delta_msr_wait); |
| |
| /* |
| * Free the IRQ and disable the port. |
| */ |
| uport->ops->shutdown(uport); |
| |
| /* |
| * Ensure that the IRQ handler isn't running on another CPU. |
| */ |
| synchronize_irq(uport->irq); |
| } |
| |
| /* |
| * kill off our tasklet |
| */ |
| tasklet_kill(&state->tlet); |
| |
| /* |
| * Free the transmit buffer page. |
| */ |
| if (state->xmit.buf) { |
| free_page((unsigned long)state->xmit.buf); |
| state->xmit.buf = NULL; |
| } |
| } |
| |
| /** |
| * uart_update_timeout - update per-port FIFO timeout. |
| * @port: uart_port structure describing the port |
| * @cflag: termios cflag value |
| * @baud: speed of the port |
| * |
| * Set the port FIFO timeout value. The @cflag value should |
| * reflect the actual hardware settings. |
| */ |
| void |
| uart_update_timeout(struct uart_port *port, unsigned int cflag, |
| unsigned int baud) |
| { |
| unsigned int bits; |
| |
| /* byte size and parity */ |
| switch (cflag & CSIZE) { |
| case CS5: |
| bits = 7; |
| break; |
| case CS6: |
| bits = 8; |
| break; |
| case CS7: |
| bits = 9; |
| break; |
| default: |
| bits = 10; |
| break; /* CS8 */ |
| } |
| |
| if (cflag & CSTOPB) |
| bits++; |
| if (cflag & PARENB) |
| bits++; |
| |
| /* |
| * The total number of bits to be transmitted in the fifo. |
| */ |
| bits = bits * port->fifosize; |
| |
| /* |
| * Figure the timeout to send the above number of bits. |
| * Add .02 seconds of slop |
| */ |
| port->timeout = (HZ * bits) / baud + HZ/50; |
| } |
| |
| EXPORT_SYMBOL(uart_update_timeout); |
| |
| /** |
| * uart_get_baud_rate - return baud rate for a particular port |
| * @port: uart_port structure describing the port in question. |
| * @termios: desired termios settings. |
| * @old: old termios (or NULL) |
| * @min: minimum acceptable baud rate |
| * @max: maximum acceptable baud rate |
| * |
| * Decode the termios structure into a numeric baud rate, |
| * taking account of the magic 38400 baud rate (with spd_* |
| * flags), and mapping the %B0 rate to 9600 baud. |
| * |
| * If the new baud rate is invalid, try the old termios setting. |
| * If it's still invalid, we try 9600 baud. |
| * |
| * Update the @termios structure to reflect the baud rate |
| * we're actually going to be using. Don't do this for the case |
| * where B0 is requested ("hang up"). |
| */ |
| unsigned int |
| uart_get_baud_rate(struct uart_port *port, struct ktermios *termios, |
| struct ktermios *old, unsigned int min, unsigned int max) |
| { |
| unsigned int try, baud, altbaud = 38400; |
| int hung_up = 0; |
| upf_t flags = port->flags & UPF_SPD_MASK; |
| |
| if (flags == UPF_SPD_HI) |
| altbaud = 57600; |
| else if (flags == UPF_SPD_VHI) |
| altbaud = 115200; |
| else if (flags == UPF_SPD_SHI) |
| altbaud = 230400; |
| else if (flags == UPF_SPD_WARP) |
| altbaud = 460800; |
| |
| for (try = 0; try < 2; try++) { |
| baud = tty_termios_baud_rate(termios); |
| |
| /* |
| * The spd_hi, spd_vhi, spd_shi, spd_warp kludge... |
| * Die! Die! Die! |
| */ |
| if (baud == 38400) |
| baud = altbaud; |
| |
| /* |
| * Special case: B0 rate. |
| */ |
| if (baud == 0) { |
| hung_up = 1; |
| baud = 9600; |
| } |
| |
| if (baud >= min && baud <= max) |
| return baud; |
| |
| /* |
| * Oops, the quotient was zero. Try again with |
| * the old baud rate if possible. |
| */ |
| termios->c_cflag &= ~CBAUD; |
| if (old) { |
| baud = tty_termios_baud_rate(old); |
| if (!hung_up) |
| tty_termios_encode_baud_rate(termios, |
| baud, baud); |
| old = NULL; |
| continue; |
| } |
| |
| /* |
| * As a last resort, if the range cannot be met then clip to |
| * the nearest chip supported rate. |
| */ |
| if (!hung_up) { |
| if (baud <= min) |
| tty_termios_encode_baud_rate(termios, |
| min + 1, min + 1); |
| else |
| tty_termios_encode_baud_rate(termios, |
| max - 1, max - 1); |
| } |
| } |
| /* Should never happen */ |
| WARN_ON(1); |
| return 0; |
| } |
| |
| EXPORT_SYMBOL(uart_get_baud_rate); |
| |
| /** |
| * uart_get_divisor - return uart clock divisor |
| * @port: uart_port structure describing the port. |
| * @baud: desired baud rate |
| * |
| * Calculate the uart clock divisor for the port. |
| */ |
| unsigned int |
| uart_get_divisor(struct uart_port *port, unsigned int baud) |
| { |
| unsigned int quot; |
| |
| /* |
| * Old custom speed handling. |
| */ |
| if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST) |
| quot = port->custom_divisor; |
| else |
| quot = (port->uartclk + (8 * baud)) / (16 * baud); |
| |
| return quot; |
| } |
| |
| EXPORT_SYMBOL(uart_get_divisor); |
| |
| /* FIXME: Consistent locking policy */ |
| static void uart_change_speed(struct tty_struct *tty, struct uart_state *state, |
| struct ktermios *old_termios) |
| { |
| struct tty_port *port = &state->port; |
| struct uart_port *uport = state->uart_port; |
| struct ktermios *termios; |
| |
| /* |
| * If we have no tty, termios, or the port does not exist, |
| * then we can't set the parameters for this port. |
| */ |
| if (!tty || !tty->termios || uport->type == PORT_UNKNOWN) |
| return; |
| |
| termios = tty->termios; |
| |
| /* |
| * Set flags based on termios cflag |
| */ |
| if (termios->c_cflag & CRTSCTS) |
| set_bit(ASYNCB_CTS_FLOW, &port->flags); |
| else |
| clear_bit(ASYNCB_CTS_FLOW, &port->flags); |
| |
| if (termios->c_cflag & CLOCAL) |
| clear_bit(ASYNCB_CHECK_CD, &port->flags); |
| else |
| set_bit(ASYNCB_CHECK_CD, &port->flags); |
| |
| uport->ops->set_termios(uport, termios, old_termios); |
| } |
| |
| static inline int __uart_put_char(struct uart_port *port, |
| struct circ_buf *circ, unsigned char c) |
| { |
| unsigned long flags; |
| int ret = 0; |
| |
| if (!circ->buf) |
| return 0; |
| |
| spin_lock_irqsave(&port->lock, flags); |
| if (uart_circ_chars_free(circ) != 0) { |
| circ->buf[circ->head] = c; |
| circ->head = (circ->head + 1) & (UART_XMIT_SIZE - 1); |
| ret = 1; |
| } |
| spin_unlock_irqrestore(&port->lock, flags); |
| return ret; |
| } |
| |
| static int uart_put_char(struct tty_struct *tty, unsigned char ch) |
| { |
| struct uart_state *state = tty->driver_data; |
| |
| return __uart_put_char(state->uart_port, &state->xmit, ch); |
| } |
| |
| static void uart_flush_chars(struct tty_struct *tty) |
| { |
| uart_start(tty); |
| } |
| |
| static int uart_write(struct tty_struct *tty, |
| const unsigned char *buf, int count) |
| { |
| struct uart_state *state = tty->driver_data; |
| struct uart_port *port; |
| struct circ_buf *circ; |
| unsigned long flags; |
| int c, ret = 0; |
| |
| /* |
| * This means you called this function _after_ the port was |
| * closed. No cookie for you. |
| */ |
| if (!state) { |
| WARN_ON(1); |
| return -EL3HLT; |
| } |
| |
| port = state->uart_port; |
| circ = &state->xmit; |
| |
| if (!circ->buf) |
| return 0; |
| |
| spin_lock_irqsave(&port->lock, flags); |
| while (1) { |
| c = CIRC_SPACE_TO_END(circ->head, circ->tail, UART_XMIT_SIZE); |
| if (count < c) |
| c = count; |
| if (c <= 0) |
| break; |
| memcpy(circ->buf + circ->head, buf, c); |
| circ->head = (circ->head + c) & (UART_XMIT_SIZE - 1); |
| buf += c; |
| count -= c; |
| ret += c; |
| } |
| spin_unlock_irqrestore(&port->lock, flags); |
| |
| uart_start(tty); |
| return ret; |
| } |
| |
| static int uart_write_room(struct tty_struct *tty) |
| { |
| struct uart_state *state = tty->driver_data; |
| unsigned long flags; |
| int ret; |
| |
| spin_lock_irqsave(&state->uart_port->lock, flags); |
| ret = uart_circ_chars_free(&state->xmit); |
| spin_unlock_irqrestore(&state->uart_port->lock, flags); |
| return ret; |
| } |
| |
| static int uart_chars_in_buffer(struct tty_struct *tty) |
| { |
| struct uart_state *state = tty->driver_data; |
| unsigned long flags; |
| int ret; |
| |
| spin_lock_irqsave(&state->uart_port->lock, flags); |
| ret = uart_circ_chars_pending(&state->xmit); |
| spin_unlock_irqrestore(&state->uart_port->lock, flags); |
| return ret; |
| } |
| |
| static void uart_flush_buffer(struct tty_struct *tty) |
| { |
| struct uart_state *state = tty->driver_data; |
| struct uart_port *port; |
| unsigned long flags; |
| |
| /* |
| * This means you called this function _after_ the port was |
| * closed. No cookie for you. |
| */ |
| if (!state) { |
| WARN_ON(1); |
| return; |
| } |
| |
| port = state->uart_port; |
| pr_debug("uart_flush_buffer(%d) called\n", tty->index); |
| |
| spin_lock_irqsave(&port->lock, flags); |
| uart_circ_clear(&state->xmit); |
| if (port->ops->flush_buffer) |
| port->ops->flush_buffer(port); |
| spin_unlock_irqrestore(&port->lock, flags); |
| tty_wakeup(tty); |
| } |
| |
| /* |
| * This function is used to send a high-priority XON/XOFF character to |
| * the device |
| */ |
| static void uart_send_xchar(struct tty_struct *tty, char ch) |
| { |
| struct uart_state *state = tty->driver_data; |
| struct uart_port *port = state->uart_port; |
| unsigned long flags; |
| |
| if (port->ops->send_xchar) |
| port->ops->send_xchar(port, ch); |
| else { |
| port->x_char = ch; |
| if (ch) { |
| spin_lock_irqsave(&port->lock, flags); |
| port->ops->start_tx(port); |
| spin_unlock_irqrestore(&port->lock, flags); |
| } |
| } |
| } |
| |
| static void uart_throttle(struct tty_struct *tty) |
| { |
| struct uart_state *state = tty->driver_data; |
| |
| if (I_IXOFF(tty)) |
| uart_send_xchar(tty, STOP_CHAR(tty)); |
| |
| if (tty->termios->c_cflag & CRTSCTS) |
| uart_clear_mctrl(state->uart_port, TIOCM_RTS); |
| } |
| |
| static void uart_unthrottle(struct tty_struct *tty) |
| { |
| struct uart_state *state = tty->driver_data; |
| struct uart_port *port = state->uart_port; |
| |
| if (I_IXOFF(tty)) { |
| if (port->x_char) |
| port->x_char = 0; |
| else |
| uart_send_xchar(tty, START_CHAR(tty)); |
| } |
| |
| if (tty->termios->c_cflag & CRTSCTS) |
| uart_set_mctrl(port, TIOCM_RTS); |
| } |
| |
| static int uart_get_info(struct uart_state *state, |
| struct serial_struct __user *retinfo) |
| { |
| struct uart_port *uport = state->uart_port; |
| struct tty_port *port = &state->port; |
| struct serial_struct tmp; |
| |
| memset(&tmp, 0, sizeof(tmp)); |
| |
| /* Ensure the state we copy is consistent and no hardware changes |
| occur as we go */ |
| mutex_lock(&port->mutex); |
| |
| tmp.type = uport->type; |
| tmp.line = uport->line; |
| tmp.port = uport->iobase; |
| if (HIGH_BITS_OFFSET) |
| tmp.port_high = (long) uport->iobase >> HIGH_BITS_OFFSET; |
| tmp.irq = uport->irq; |
| tmp.flags = uport->flags; |
| tmp.xmit_fifo_size = uport->fifosize; |
| tmp.baud_base = uport->uartclk / 16; |
| tmp.close_delay = port->close_delay / 10; |
| tmp.closing_wait = port->closing_wait == ASYNC_CLOSING_WAIT_NONE ? |
| ASYNC_CLOSING_WAIT_NONE : |
| port->closing_wait / 10; |
| tmp.custom_divisor = uport->custom_divisor; |
| tmp.hub6 = uport->hub6; |
| tmp.io_type = uport->iotype; |
| tmp.iomem_reg_shift = uport->regshift; |
| tmp.iomem_base = (void *)(unsigned long)uport->mapbase; |
| |
| mutex_unlock(&port->mutex); |
| |
| if (copy_to_user(retinfo, &tmp, sizeof(*retinfo))) |
| return -EFAULT; |
| return 0; |
| } |
| |
| static int uart_set_info(struct tty_struct *tty, struct uart_state *state, |
| struct serial_struct __user *newinfo) |
| { |
| struct serial_struct new_serial; |
| struct uart_port *uport = state->uart_port; |
| struct tty_port *port = &state->port; |
| unsigned long new_port; |
| unsigned int change_irq, change_port, closing_wait; |
| unsigned int old_custom_divisor, close_delay; |
| upf_t old_flags, new_flags; |
| int retval = 0; |
| |
| if (copy_from_user(&new_serial, newinfo, sizeof(new_serial))) |
| return -EFAULT; |
| |
| new_port = new_serial.port; |
| if (HIGH_BITS_OFFSET) |
| new_port += (unsigned long) new_serial.port_high << HIGH_BITS_OFFSET; |
| |
| new_serial.irq = irq_canonicalize(new_serial.irq); |
| close_delay = new_serial.close_delay * 10; |
| closing_wait = new_serial.closing_wait == ASYNC_CLOSING_WAIT_NONE ? |
| ASYNC_CLOSING_WAIT_NONE : new_serial.closing_wait * 10; |
| |
| /* |
| * This semaphore protects port->count. It is also |
| * very useful to prevent opens. Also, take the |
| * port configuration semaphore to make sure that a |
| * module insertion/removal doesn't change anything |
| * under us. |
| */ |
| mutex_lock(&port->mutex); |
| |
| change_irq = !(uport->flags & UPF_FIXED_PORT) |
| && new_serial.irq != uport->irq; |
| |
| /* |
| * Since changing the 'type' of the port changes its resource |
| * allocations, we should treat type changes the same as |
| * IO port changes. |
| */ |
| change_port = !(uport->flags & UPF_FIXED_PORT) |
| && (new_port != uport->iobase || |
| (unsigned long)new_serial.iomem_base != uport->mapbase || |
| new_serial.hub6 != uport->hub6 || |
| new_serial.io_type != uport->iotype || |
| new_serial.iomem_reg_shift != uport->regshift || |
| new_serial.type != uport->type); |
| |
| old_flags = uport->flags; |
| new_flags = new_serial.flags; |
| old_custom_divisor = uport->custom_divisor; |
| |
| if (!capable(CAP_SYS_ADMIN)) { |
| retval = -EPERM; |
| if (change_irq || change_port || |
| (new_serial.baud_base != uport->uartclk / 16) || |
| (close_delay != port->close_delay) || |
| (closing_wait != port->closing_wait) || |
| (new_serial.xmit_fifo_size && |
| new_serial.xmit_fifo_size != uport->fifosize) || |
| (((new_flags ^ old_flags) & ~UPF_USR_MASK) != 0)) |
| goto exit; |
| uport->flags = ((uport->flags & ~UPF_USR_MASK) | |
| (new_flags & UPF_USR_MASK)); |
| uport->custom_divisor = new_serial.custom_divisor; |
| goto check_and_exit; |
| } |
| |
| /* |
| * Ask the low level driver to verify the settings. |
| */ |
| if (uport->ops->verify_port) |
| retval = uport->ops->verify_port(uport, &new_serial); |
| |
| if ((new_serial.irq >= nr_irqs) || (new_serial.irq < 0) || |
| (new_serial.baud_base < 9600)) |
| retval = -EINVAL; |
| |
| if (retval) |
| goto exit; |
| |
| if (change_port || change_irq) { |
| retval = -EBUSY; |
| |
| /* |
| * Make sure that we are the sole user of this port. |
| */ |
| if (tty_port_users(port) > 1) |
| goto exit; |
| |
| /* |
| * We need to shutdown the serial port at the old |
| * port/type/irq combination. |
| */ |
| uart_shutdown(tty, state); |
| } |
| |
| if (change_port) { |
| unsigned long old_iobase, old_mapbase; |
| unsigned int old_type, old_iotype, old_hub6, old_shift; |
| |
| old_iobase = uport->iobase; |
| old_mapbase = uport->mapbase; |
| old_type = uport->type; |
| old_hub6 = uport->hub6; |
| old_iotype = uport->iotype; |
| old_shift = uport->regshift; |
| |
| /* |
| * Free and release old regions |
| */ |
| if (old_type != PORT_UNKNOWN) |
| uport->ops->release_port(uport); |
| |
| uport->iobase = new_port; |
| uport->type = new_serial.type; |
| uport->hub6 = new_serial.hub6; |
| uport->iotype = new_serial.io_type; |
| uport->regshift = new_serial.iomem_reg_shift; |
| uport->mapbase = (unsigned long)new_serial.iomem_base; |
| |
| /* |
| * Claim and map the new regions |
| */ |
| if (uport->type != PORT_UNKNOWN) { |
| retval = uport->ops->request_port(uport); |
| } else { |
| /* Always success - Jean II */ |
| retval = 0; |
| } |
| |
| /* |
| * If we fail to request resources for the |
| * new port, try to restore the old settings. |
| */ |
| if (retval && old_type != PORT_UNKNOWN) { |
| uport->iobase = old_iobase; |
| uport->type = old_type; |
| uport->hub6 = old_hub6; |
| uport->iotype = old_iotype; |
| uport->regshift = old_shift; |
| uport->mapbase = old_mapbase; |
| retval = uport->ops->request_port(uport); |
| /* |
| * If we failed to restore the old settings, |
| * we fail like this. |
| */ |
| if (retval) |
| uport->type = PORT_UNKNOWN; |
| |
| /* |
| * We failed anyway. |
| */ |
| retval = -EBUSY; |
| /* Added to return the correct error -Ram Gupta */ |
| goto exit; |
| } |
| } |
| |
| if (change_irq) |
| uport->irq = new_serial.irq; |
| if (!(uport->flags & UPF_FIXED_PORT)) |
| uport->uartclk = new_serial.baud_base * 16; |
| uport->flags = (uport->flags & ~UPF_CHANGE_MASK) | |
| (new_flags & UPF_CHANGE_MASK); |
| uport->custom_divisor = new_serial.custom_divisor; |
| port->close_delay = close_delay; |
| port->closing_wait = closing_wait; |
| if (new_serial.xmit_fifo_size) |
| uport->fifosize = new_serial.xmit_fifo_size; |
| if (port->tty) |
| port->tty->low_latency = |
| (uport->flags & UPF_LOW_LATENCY) ? 1 : 0; |
| |
| check_and_exit: |
| retval = 0; |
| if (uport->type == PORT_UNKNOWN) |
| goto exit; |
| if (port->flags & ASYNC_INITIALIZED) { |
| if (((old_flags ^ uport->flags) & UPF_SPD_MASK) || |
| old_custom_divisor != uport->custom_divisor) { |
| /* |
| * If they're setting up a custom divisor or speed, |
| * instead of clearing it, then bitch about it. No |
| * need to rate-limit; it's CAP_SYS_ADMIN only. |
| */ |
| if (uport->flags & UPF_SPD_MASK) { |
| char buf[64]; |
| printk(KERN_NOTICE |
| "%s sets custom speed on %s. This " |
| "is deprecated.\n", current->comm, |
| tty_name(port->tty, buf)); |
| } |
| uart_change_speed(tty, state, NULL); |
| } |
| } else |
| retval = uart_startup(tty, state, 1); |
| exit: |
| mutex_unlock(&port->mutex); |
| return retval; |
| } |
| |
| /** |
| * uart_get_lsr_info - get line status register info |
| * @tty: tty associated with the UART |
| * @state: UART being queried |
| * @value: returned modem value |
| * |
| * Note: uart_ioctl protects us against hangups. |
| */ |
| static int uart_get_lsr_info(struct tty_struct *tty, |
| struct uart_state *state, unsigned int __user *value) |
| { |
| struct uart_port *uport = state->uart_port; |
| unsigned int result; |
| |
| result = uport->ops->tx_empty(uport); |
| |
| /* |
| * If we're about to load something into the transmit |
| * register, we'll pretend the transmitter isn't empty to |
| * avoid a race condition (depending on when the transmit |
| * interrupt happens). |
| */ |
| if (uport->x_char || |
| ((uart_circ_chars_pending(&state->xmit) > 0) && |
| !tty->stopped && !tty->hw_stopped)) |
| result &= ~TIOCSER_TEMT; |
| |
| return put_user(result, value); |
| } |
| |
| static int uart_tiocmget(struct tty_struct *tty) |
| { |
| struct uart_state *state = tty->driver_data; |
| struct tty_port *port = &state->port; |
| struct uart_port *uport = state->uart_port; |
| int result = -EIO; |
| |
| mutex_lock(&port->mutex); |
| if (!(tty->flags & (1 << TTY_IO_ERROR))) { |
| result = uport->mctrl; |
| spin_lock_irq(&uport->lock); |
| result |= uport->ops->get_mctrl(uport); |
| spin_unlock_irq(&uport->lock); |
| } |
| mutex_unlock(&port->mutex); |
| |
| return result; |
| } |
| |
| static int |
| uart_tiocmset(struct tty_struct *tty, unsigned int set, unsigned int clear) |
| { |
| struct uart_state *state = tty->driver_data; |
| struct uart_port *uport = state->uart_port; |
| struct tty_port *port = &state->port; |
| int ret = -EIO; |
| |
| mutex_lock(&port->mutex); |
| if (!(tty->flags & (1 << TTY_IO_ERROR))) { |
| uart_update_mctrl(uport, set, clear); |
| ret = 0; |
| } |
| mutex_unlock(&port->mutex); |
| return ret; |
| } |
| |
| static int uart_break_ctl(struct tty_struct *tty, int break_state) |
| { |
| struct uart_state *state = tty->driver_data; |
| struct tty_port *port = &state->port; |
| struct uart_port *uport = state->uart_port; |
| |
| mutex_lock(&port->mutex); |
| |
| if (uport->type != PORT_UNKNOWN) |
| uport->ops->break_ctl(uport, break_state); |
| |
| mutex_unlock(&port->mutex); |
| return 0; |
| } |
| |
| static int uart_do_autoconfig(struct tty_struct *tty,struct uart_state *state) |
| { |
| struct uart_port *uport = state->uart_port; |
| struct tty_port *port = &state->port; |
| int flags, ret; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| /* |
| * Take the per-port semaphore. This prevents count from |
| * changing, and hence any extra opens of the port while |
| * we're auto-configuring. |
| */ |
| if (mutex_lock_interruptible(&port->mutex)) |
| return -ERESTARTSYS; |
| |
| ret = -EBUSY; |
| if (tty_port_users(port) == 1) { |
| uart_shutdown(tty, state); |
| |
| /* |
| * If we already have a port type configured, |
| * we must release its resources. |
| */ |
| if (uport->type != PORT_UNKNOWN) |
| uport->ops->release_port(uport); |
| |
| flags = UART_CONFIG_TYPE; |
| if (uport->flags & UPF_AUTO_IRQ) |
| flags |= UART_CONFIG_IRQ; |
| |
| /* |
| * This will claim the ports resources if |
| * a port is found. |
| */ |
| uport->ops->config_port(uport, flags); |
| |
| ret = uart_startup(tty, state, 1); |
| } |
| mutex_unlock(&port->mutex); |
| return ret; |
| } |
| |
| /* |
| * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change |
| * - mask passed in arg for lines of interest |
| * (use |'ed TIOCM_RNG/DSR/CD/CTS for masking) |
| * Caller should use TIOCGICOUNT to see which one it was |
| * |
| * FIXME: This wants extracting into a common all driver implementation |
| * of TIOCMWAIT using tty_port. |
| */ |
| static int |
| uart_wait_modem_status(struct uart_state *state, unsigned long arg) |
| { |
| struct uart_port *uport = state->uart_port; |
| struct tty_port *port = &state->port; |
| DECLARE_WAITQUEUE(wait, current); |
| struct uart_icount cprev, cnow; |
| int ret; |
| |
| /* |
| * note the counters on entry |
| */ |
| spin_lock_irq(&uport->lock); |
| memcpy(&cprev, &uport->icount, sizeof(struct uart_icount)); |
| |
| /* |
| * Force modem status interrupts on |
| */ |
| uport->ops->enable_ms(uport); |
| spin_unlock_irq(&uport->lock); |
| |
| add_wait_queue(&port->delta_msr_wait, &wait); |
| for (;;) { |
| spin_lock_irq(&uport->lock); |
| memcpy(&cnow, &uport->icount, sizeof(struct uart_icount)); |
| spin_unlock_irq(&uport->lock); |
| |
| set_current_state(TASK_INTERRUPTIBLE); |
| |
| if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) || |
| ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) || |
| ((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) || |
| ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) { |
| ret = 0; |
| break; |
| } |
| |
| schedule(); |
| |
| /* see if a signal did it */ |
| if (signal_pending(current)) { |
| ret = -ERESTARTSYS; |
| break; |
| } |
| |
| cprev = cnow; |
| } |
| |
| current->state = TASK_RUNNING; |
| remove_wait_queue(&port->delta_msr_wait, &wait); |
| |
| return ret; |
| } |
| |
| /* |
| * Get counter of input serial line interrupts (DCD,RI,DSR,CTS) |
| * Return: write counters to the user passed counter struct |
| * NB: both 1->0 and 0->1 transitions are counted except for |
| * RI where only 0->1 is counted. |
| */ |
| static int uart_get_icount(struct tty_struct *tty, |
| struct serial_icounter_struct *icount) |
| { |
| struct uart_state *state = tty->driver_data; |
| struct uart_icount cnow; |
| struct uart_port *uport = state->uart_port; |
| |
| spin_lock_irq(&uport->lock); |
| memcpy(&cnow, &uport->icount, sizeof(struct uart_icount)); |
| spin_unlock_irq(&uport->lock); |
| |
| icount->cts = cnow.cts; |
| icount->dsr = cnow.dsr; |
| icount->rng = cnow.rng; |
| icount->dcd = cnow.dcd; |
| icount->rx = cnow.rx; |
| icount->tx = cnow.tx; |
| icount->frame = cnow.frame; |
| icount->overrun = cnow.overrun; |
| icount->parity = cnow.parity; |
| icount->brk = cnow.brk; |
| icount->buf_overrun = cnow.buf_overrun; |
| |
| return 0; |
| } |
| |
| /* |
| * Called via sys_ioctl. We can use spin_lock_irq() here. |
| */ |
| static int |
| uart_ioctl(struct tty_struct *tty, unsigned int cmd, |
| unsigned long arg) |
| { |
| struct uart_state *state = tty->driver_data; |
| struct tty_port *port = &state->port; |
| void __user *uarg = (void __user *)arg; |
| int ret = -ENOIOCTLCMD; |
| |
| |
| /* |
| * These ioctls don't rely on the hardware to be present. |
| */ |
| switch (cmd) { |
| case TIOCGSERIAL: |
| ret = uart_get_info(state, uarg); |
| break; |
| |
| case TIOCSSERIAL: |
| ret = uart_set_info(tty, state, uarg); |
| break; |
| |
| case TIOCSERCONFIG: |
| ret = uart_do_autoconfig(tty, state); |
| break; |
| |
| case TIOCSERGWILD: /* obsolete */ |
| case TIOCSERSWILD: /* obsolete */ |
| ret = 0; |
| break; |
| } |
| |
| if (ret != -ENOIOCTLCMD) |
| goto out; |
| |
| if (tty->flags & (1 << TTY_IO_ERROR)) { |
| ret = -EIO; |
| goto out; |
| } |
| |
| /* |
| * The following should only be used when hardware is present. |
| */ |
| switch (cmd) { |
| case TIOCMIWAIT: |
| ret = uart_wait_modem_status(state, arg); |
| break; |
| } |
| |
| if (ret != -ENOIOCTLCMD) |
| goto out; |
| |
| mutex_lock(&port->mutex); |
| |
| if (tty->flags & (1 << TTY_IO_ERROR)) { |
| ret = -EIO; |
| goto out_up; |
| } |
| |
| /* |
| * All these rely on hardware being present and need to be |
| * protected against the tty being hung up. |
| */ |
| switch (cmd) { |
| case TIOCSERGETLSR: /* Get line status register */ |
| ret = uart_get_lsr_info(tty, state, uarg); |
| break; |
| |
| default: { |
| struct uart_port *uport = state->uart_port; |
| if (uport->ops->ioctl) |
| ret = uport->ops->ioctl(uport, cmd, arg); |
| break; |
| } |
| } |
| out_up: |
| mutex_unlock(&port->mutex); |
| out: |
| return ret; |
| } |
| |
| static void uart_set_ldisc(struct tty_struct *tty) |
| { |
| struct uart_state *state = tty->driver_data; |
| struct uart_port *uport = state->uart_port; |
| |
| if (uport->ops->set_ldisc) |
| uport->ops->set_ldisc(uport, tty->termios->c_line); |
| } |
| |
| static void uart_set_termios(struct tty_struct *tty, |
| struct ktermios *old_termios) |
| { |
| struct uart_state *state = tty->driver_data; |
| unsigned long flags; |
| unsigned int cflag = tty->termios->c_cflag; |
| |
| |
| /* |
| * These are the bits that are used to setup various |
| * flags in the low level driver. We can ignore the Bfoo |
| * bits in c_cflag; c_[io]speed will always be set |
| * appropriately by set_termios() in tty_ioctl.c |
| */ |
| #define RELEVANT_IFLAG(iflag) ((iflag) & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK)) |
| if ((cflag ^ old_termios->c_cflag) == 0 && |
| tty->termios->c_ospeed == old_termios->c_ospeed && |
| tty->termios->c_ispeed == old_termios->c_ispeed && |
| RELEVANT_IFLAG(tty->termios->c_iflag ^ old_termios->c_iflag) == 0) { |
| return; |
| } |
| |
| uart_change_speed(tty, state, old_termios); |
| |
| /* Handle transition to B0 status */ |
| if ((old_termios->c_cflag & CBAUD) && !(cflag & CBAUD)) |
| uart_clear_mctrl(state->uart_port, TIOCM_RTS | TIOCM_DTR); |
| /* Handle transition away from B0 status */ |
| else if (!(old_termios->c_cflag & CBAUD) && (cflag & CBAUD)) { |
| unsigned int mask = TIOCM_DTR; |
| if (!(cflag & CRTSCTS) || |
| !test_bit(TTY_THROTTLED, &tty->flags)) |
| mask |= TIOCM_RTS; |
| uart_set_mctrl(state->uart_port, mask); |
| } |
| |
| /* Handle turning off CRTSCTS */ |
| if ((old_termios->c_cflag & CRTSCTS) && !(cflag & CRTSCTS)) { |
| spin_lock_irqsave(&state->uart_port->lock, flags); |
| tty->hw_stopped = 0; |
| __uart_start(tty); |
| spin_unlock_irqrestore(&state->uart_port->lock, flags); |
| } |
| /* Handle turning on CRTSCTS */ |
| else if (!(old_termios->c_cflag & CRTSCTS) && (cflag & CRTSCTS)) { |
| spin_lock_irqsave(&state->uart_port->lock, flags); |
| if (!(state->uart_port->ops->get_mctrl(state->uart_port) & TIOCM_CTS)) { |
| tty->hw_stopped = 1; |
| state->uart_port->ops->stop_tx(state->uart_port); |
| } |
| spin_unlock_irqrestore(&state->uart_port->lock, flags); |
| } |
| } |
| |
| /* |
| * In 2.4.5, calls to this will be serialized via the BKL in |
| * linux/drivers/char/tty_io.c:tty_release() |
| * linux/drivers/char/tty_io.c:do_tty_handup() |
| */ |
| static void uart_close(struct tty_struct *tty, struct file *filp) |
| { |
| struct uart_state *state = tty->driver_data; |
| struct tty_port *port; |
| struct uart_port *uport; |
| unsigned long flags; |
| |
| BUG_ON(!tty_locked()); |
| |
| if (!state) |
| return; |
| |
| uport = state->uart_port; |
| port = &state->port; |
| |
| pr_debug("uart_close(%d) called\n", uport->line); |
| |
| mutex_lock(&port->mutex); |
| spin_lock_irqsave(&port->lock, flags); |
| |
| if (tty_hung_up_p(filp)) { |
| spin_unlock_irqrestore(&port->lock, flags); |
| goto done; |
| } |
| |
| if ((tty->count == 1) && (port->count != 1)) { |
| /* |
| * Uh, oh. tty->count is 1, which means that the tty |
| * structure will be freed. port->count should always |
| * be one in these conditions. If it's greater than |
| * one, we've got real problems, since it means the |
| * serial port won't be shutdown. |
| */ |
| printk(KERN_ERR "uart_close: bad serial port count; tty->count is 1, " |
| "port->count is %d\n", port->count); |
| port->count = 1; |
| } |
| if (--port->count < 0) { |
| printk(KERN_ERR "uart_close: bad serial port count for %s: %d\n", |
| tty->name, port->count); |
| port->count = 0; |
| } |
| if (port->count) { |
| spin_unlock_irqrestore(&port->lock, flags); |
| goto done; |
| } |
| |
| /* |
| * Now we wait for the transmit buffer to clear; and we notify |
| * the line discipline to only process XON/XOFF characters by |
| * setting tty->closing. |
| */ |
| tty->closing = 1; |
| spin_unlock_irqrestore(&port->lock, flags); |
| |
| if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE) { |
| /* |
| * hack: open-coded tty_wait_until_sent to avoid |
| * recursive tty_lock |
| */ |
| long timeout = msecs_to_jiffies(port->closing_wait); |
| if (wait_event_interruptible_timeout(tty->write_wait, |
| !tty_chars_in_buffer(tty), timeout) >= 0) |
| __uart_wait_until_sent(uport, timeout); |
| } |
| |
| /* |
| * At this point, we stop accepting input. To do this, we |
| * disable the receive line status interrupts. |
| */ |
| if (port->flags & ASYNC_INITIALIZED) { |
| unsigned long flags; |
| spin_lock_irqsave(&uport->lock, flags); |
| uport->ops->stop_rx(uport); |
| spin_unlock_irqrestore(&uport->lock, flags); |
| /* |
| * Before we drop DTR, make sure the UART transmitter |
| * has completely drained; this is especially |
| * important if there is a transmit FIFO! |
| */ |
| __uart_wait_until_sent(uport, uport->timeout); |
| } |
| |
| uart_shutdown(tty, state); |
| uart_flush_buffer(tty); |
| |
| tty_ldisc_flush(tty); |
| |
| tty_port_tty_set(port, NULL); |
| spin_lock_irqsave(&port->lock, flags); |
| tty->closing = 0; |
| |
| if (port->blocked_open) { |
| spin_unlock_irqrestore(&port->lock, flags); |
| if (port->close_delay) |
| msleep_interruptible(port->close_delay); |
| spin_lock_irqsave(&port->lock, flags); |
| } else if (!uart_console(uport)) { |
| spin_unlock_irqrestore(&port->lock, flags); |
| uart_change_pm(state, 3); |
| spin_lock_irqsave(&port->lock, flags); |
| } |
| |
| /* |
| * Wake up anyone trying to open this port. |
| */ |
| clear_bit(ASYNCB_NORMAL_ACTIVE, &port->flags); |
| spin_unlock_irqrestore(&port->lock, flags); |
| wake_up_interruptible(&port->open_wait); |
| |
| done: |
| mutex_unlock(&port->mutex); |
| } |
| |
| static void __uart_wait_until_sent(struct uart_port *port, int timeout) |
| { |
| unsigned long char_time, expire; |
| |
| if (port->type == PORT_UNKNOWN || port->fifosize == 0) |
| return; |
| |
| /* |
| * Set the check interval to be 1/5 of the estimated time to |
| * send a single character, and make it at least 1. The check |
| * interval should also be less than the timeout. |
| * |
| * Note: we have to use pretty tight timings here to satisfy |
| * the NIST-PCTS. |
| */ |
| char_time = (port->timeout - HZ/50) / port->fifosize; |
| char_time = char_time / 5; |
| if (char_time == 0) |
| char_time = 1; |
| if (timeout && timeout < char_time) |
| char_time = timeout; |
| |
| /* |
| * If the transmitter hasn't cleared in twice the approximate |
| * amount of time to send the entire FIFO, it probably won't |
| * ever clear. This assumes the UART isn't doing flow |
| * control, which is currently the case. Hence, if it ever |
| * takes longer than port->timeout, this is probably due to a |
| * UART bug of some kind. So, we clamp the timeout parameter at |
| * 2*port->timeout. |
| */ |
| if (timeout == 0 || timeout > 2 * port->timeout) |
| timeout = 2 * port->timeout; |
| |
| expire = jiffies + timeout; |
| |
| pr_debug("uart_wait_until_sent(%d), jiffies=%lu, expire=%lu...\n", |
| port->line, jiffies, expire); |
| |
| /* |
| * Check whether the transmitter is empty every 'char_time'. |
| * 'timeout' / 'expire' give us the maximum amount of time |
| * we wait. |
| */ |
| while (!port->ops->tx_empty(port)) { |
| msleep_interruptible(jiffies_to_msecs(char_time)); |
| if (signal_pending(current)) |
| break; |
| if (time_after(jiffies, expire)) |
| break; |
| } |
| } |
| |
| static void uart_wait_until_sent(struct tty_struct *tty, int timeout) |
| { |
| struct uart_state *state = tty->driver_data; |
| struct uart_port *port = state->uart_port; |
| |
| tty_lock(); |
| __uart_wait_until_sent(port, timeout); |
| tty_unlock(); |
| } |
| |
| /* |
| * This is called with the BKL held in |
| * linux/drivers/char/tty_io.c:do_tty_hangup() |
| * We're called from the eventd thread, so we can sleep for |
| * a _short_ time only. |
| */ |
| static void uart_hangup(struct tty_struct *tty) |
| { |
| struct uart_state *state = tty->driver_data; |
| struct tty_port *port = &state->port; |
| unsigned long flags; |
| |
| BUG_ON(!tty_locked()); |
| pr_debug("uart_hangup(%d)\n", state->uart_port->line); |
| |
| mutex_lock(&port->mutex); |
| if (port->flags & ASYNC_NORMAL_ACTIVE) { |
| uart_flush_buffer(tty); |
| uart_shutdown(tty, state); |
| spin_lock_irqsave(&port->lock, flags); |
| port->count = 0; |
| clear_bit(ASYNCB_NORMAL_ACTIVE, &port->flags); |
| spin_unlock_irqrestore(&port->lock, flags); |
| tty_port_tty_set(port, NULL); |
| wake_up_interruptible(&port->open_wait); |
| wake_up_interruptible(&port->delta_msr_wait); |
| } |
| mutex_unlock(&port->mutex); |
| } |
| |
| static int uart_carrier_raised(struct tty_port *port) |
| { |
| struct uart_state *state = container_of(port, struct uart_state, port); |
| struct uart_port *uport = state->uart_port; |
| int mctrl; |
| spin_lock_irq(&uport->lock); |
| uport->ops->enable_ms(uport); |
| mctrl = uport->ops->get_mctrl(uport); |
| spin_unlock_irq(&uport->lock); |
| if (mctrl & TIOCM_CAR) |
| return 1; |
| return 0; |
| } |
| |
| static void uart_dtr_rts(struct tty_port *port, int onoff) |
| { |
| struct uart_state *state = container_of(port, struct uart_state, port); |
| struct uart_port *uport = state->uart_port; |
| |
| if (onoff) |
| uart_set_mctrl(uport, TIOCM_DTR | TIOCM_RTS); |
| else |
| uart_clear_mctrl(uport, TIOCM_DTR | TIOCM_RTS); |
| } |
| |
| static struct uart_state *uart_get(struct uart_driver *drv, int line) |
| { |
| struct uart_state *state; |
| struct tty_port *port; |
| int ret = 0; |
| |
| state = drv->state + line; |
| port = &state->port; |
| if (mutex_lock_interruptible(&port->mutex)) { |
| ret = -ERESTARTSYS; |
| goto err; |
| } |
| |
| port->count++; |
| if (!state->uart_port || state->uart_port->flags & UPF_DEAD) { |
| ret = -ENXIO; |
| goto err_unlock; |
| } |
| return state; |
| |
| err_unlock: |
| port->count--; |
| mutex_unlock(&port->mutex); |
| err: |
| return ERR_PTR(ret); |
| } |
| |
| /* |
| * calls to uart_open are serialised by the BKL in |
| * fs/char_dev.c:chrdev_open() |
| * Note that if this fails, then uart_close() _will_ be called. |
| * |
| * In time, we want to scrap the "opening nonpresent ports" |
| * behaviour and implement an alternative way for setserial |
| * to set base addresses/ports/types. This will allow us to |
| * get rid of a certain amount of extra tests. |
| */ |
| static int uart_open(struct tty_struct *tty, struct file *filp) |
| { |
| struct uart_driver *drv = (struct uart_driver *)tty->driver->driver_state; |
| struct uart_state *state; |
| struct tty_port *port; |
| int retval, line = tty->index; |
| |
| BUG_ON(!tty_locked()); |
| pr_debug("uart_open(%d) called\n", line); |
| |
| /* |
| * We take the semaphore inside uart_get to guarantee that we won't |
| * be re-entered while allocating the state structure, or while we |
| * request any IRQs that the driver may need. This also has the nice |
| * side-effect that it delays the action of uart_hangup, so we can |
| * guarantee that state->port.tty will always contain something |
| * reasonable. |
| */ |
| state = uart_get(drv, line); |
| if (IS_ERR(state)) { |
| retval = PTR_ERR(state); |
| goto fail; |
| } |
| port = &state->port; |
| |
| /* |
| * Once we set tty->driver_data here, we are guaranteed that |
| * uart_close() will decrement the driver module use count. |
| * Any failures from here onwards should not touch the count. |
| */ |
| tty->driver_data = state; |
| state->uart_port->state = state; |
| tty->low_latency = (state->uart_port->flags & UPF_LOW_LATENCY) ? 1 : 0; |
| tty->alt_speed = 0; |
| tty_port_tty_set(port, tty); |
| |
| /* |
| * If the port is in the middle of closing, bail out now. |
| */ |
| if (tty_hung_up_p(filp)) { |
| retval = -EAGAIN; |
| port->count--; |
| mutex_unlock(&port->mutex); |
| goto fail; |
| } |
| |
| /* |
| * Make sure the device is in D0 state. |
| */ |
| if (port->count == 1) |
| uart_change_pm(state, 0); |
| |
| /* |
| * Start up the serial port. |
| */ |
| retval = uart_startup(tty, state, 0); |
| |
| /* |
| * If we succeeded, wait until the port is ready. |
| */ |
| mutex_unlock(&port->mutex); |
| if (retval == 0) |
| retval = tty_port_block_til_ready(port, tty, filp); |
| |
| fail: |
| return retval; |
| } |
| |
| static const char *uart_type(struct uart_port *port) |
| { |
| const char *str = NULL; |
| |
| if (port->ops->type) |
| str = port->ops->type(port); |
| |
| if (!str) |
| str = "unknown"; |
| |
| return str; |
| } |
| |
| #ifdef CONFIG_PROC_FS |
| |
| static void uart_line_info(struct seq_file *m, struct uart_driver *drv, int i) |
| { |
| struct uart_state *state = drv->state + i; |
| struct tty_port *port = &state->port; |
| int pm_state; |
| struct uart_port *uport = state->uart_port; |
| char stat_buf[32]; |
| unsigned int status; |
| int mmio; |
| |
| if (!uport) |
| return; |
| |
| mmio = uport->iotype >= UPIO_MEM; |
| seq_printf(m, "%d: uart:%s %s%08llX irq:%d", |
| uport->line, uart_type(uport), |
| mmio ? "mmio:0x" : "port:", |
| mmio ? (unsigned long long)uport->mapbase |
| : (unsigned long long)uport->iobase, |
| uport->irq); |
| |
| if (uport->type == PORT_UNKNOWN) { |
| seq_putc(m, '\n'); |
| return; |
| } |
| |
| if (capable(CAP_SYS_ADMIN)) { |
| mutex_lock(&port->mutex); |
| pm_state = state->pm_state; |
| if (pm_state) |
| uart_change_pm(state, 0); |
| spin_lock_irq(&uport->lock); |
| status = uport->ops->get_mctrl(uport); |
| spin_unlock_irq(&uport->lock); |
| if (pm_state) |
| uart_change_pm(state, pm_state); |
| mutex_unlock(&port->mutex); |
| |
| seq_printf(m, " tx:%d rx:%d", |
| uport->icount.tx, uport->icount.rx); |
| if (uport->icount.frame) |
| seq_printf(m, " fe:%d", |
| uport->icount.frame); |
| if (uport->icount.parity) |
| seq_printf(m, " pe:%d", |
| uport->icount.parity); |
| if (uport->icount.brk) |
| seq_printf(m, " brk:%d", |
| uport->icount.brk); |
| if (uport->icount.overrun) |
| seq_printf(m, " oe:%d", |
| uport->icount.overrun); |
| |
| #define INFOBIT(bit, str) \ |
| if (uport->mctrl & (bit)) \ |
| strncat(stat_buf, (str), sizeof(stat_buf) - \ |
| strlen(stat_buf) - 2) |
| #define STATBIT(bit, str) \ |
| if (status & (bit)) \ |
| strncat(stat_buf, (str), sizeof(stat_buf) - \ |
| strlen(stat_buf) - 2) |
| |
| stat_buf[0] = '\0'; |
| stat_buf[1] = '\0'; |
| INFOBIT(TIOCM_RTS, "|RTS"); |
| STATBIT(TIOCM_CTS, "|CTS"); |
| INFOBIT(TIOCM_DTR, "|DTR"); |
| STATBIT(TIOCM_DSR, "|DSR"); |
| STATBIT(TIOCM_CAR, "|CD"); |
| STATBIT(TIOCM_RNG, "|RI"); |
| if (stat_buf[0]) |
| stat_buf[0] = ' '; |
| |
| seq_puts(m, stat_buf); |
| } |
| seq_putc(m, '\n'); |
| #undef STATBIT |
| #undef INFOBIT |
| } |
| |
| static int uart_proc_show(struct seq_file *m, void *v) |
| { |
| struct tty_driver *ttydrv = m->private; |
| struct uart_driver *drv = ttydrv->driver_state; |
| int i; |
| |
| seq_printf(m, "serinfo:1.0 driver%s%s revision:%s\n", |
| "", "", ""); |
| for (i = 0; i < drv->nr; i++) |
| uart_line_info(m, drv, i); |
| return 0; |
| } |
| |
| static int uart_proc_open(struct inode *inode, struct file *file) |
| { |
| return single_open(file, uart_proc_show, PDE(inode)->data); |
| } |
| |
| static const struct file_operations uart_proc_fops = { |
| .owner = THIS_MODULE, |
| .open = uart_proc_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| #endif |
| |
| #if defined(CONFIG_SERIAL_CORE_CONSOLE) || defined(CONFIG_CONSOLE_POLL) |
| /* |
| * uart_console_write - write a console message to a serial port |
| * @port: the port to write the message |
| * @s: array of characters |
| * @count: number of characters in string to write |
| * @write: function to write character to port |
| */ |
| void uart_console_write(struct uart_port *port, const char *s, |
| unsigned int count, |
| void (*putchar)(struct uart_port *, int)) |
| { |
| unsigned int i; |
| |
| for (i = 0; i < count; i++, s++) { |
| if (*s == '\n') |
| putchar(port, '\r'); |
| putchar(port, *s); |
| } |
| } |
| EXPORT_SYMBOL_GPL(uart_console_write); |
| |
| /* |
| * Check whether an invalid uart number has been specified, and |
| * if so, search for the first available port that does have |
| * console support. |
| */ |
| struct uart_port * __init |
| uart_get_console(struct uart_port *ports, int nr, struct console *co) |
| { |
| int idx = co->index; |
| |
| if (idx < 0 || idx >= nr || (ports[idx].iobase == 0 && |
| ports[idx].membase == NULL)) |
| for (idx = 0; idx < nr; idx++) |
| if (ports[idx].iobase != 0 || |
| ports[idx].membase != NULL) |
| break; |
| |
| co->index = idx; |
| |
| return ports + idx; |
| } |
| |
| /** |
| * uart_parse_options - Parse serial port baud/parity/bits/flow contro. |
| * @options: pointer to option string |
| * @baud: pointer to an 'int' variable for the baud rate. |
| * @parity: pointer to an 'int' variable for the parity. |
| * @bits: pointer to an 'int' variable for the number of data bits. |
| * @flow: pointer to an 'int' variable for the flow control character. |
| * |
| * uart_parse_options decodes a string containing the serial console |
| * options. The format of the string is <baud><parity><bits><flow>, |
| * eg: 115200n8r |
| */ |
| void |
| uart_parse_options(char *options, int *baud, int *parity, int *bits, int *flow) |
| { |
| char *s = options; |
| |
| *baud = simple_strtoul(s, NULL, 10); |
| while (*s >= '0' && *s <= '9') |
| s++; |
| if (*s) |
| *parity = *s++; |
| if (*s) |
| *bits = *s++ - '0'; |
| if (*s) |
| *flow = *s; |
| } |
| EXPORT_SYMBOL_GPL(uart_parse_options); |
| |
| struct baud_rates { |
| unsigned int rate; |
| unsigned int cflag; |
| }; |
| |
| static const struct baud_rates baud_rates[] = { |
| { 921600, B921600 }, |
| { 460800, B460800 }, |
| { 230400, B230400 }, |
| { 115200, B115200 }, |
| { 57600, B57600 }, |
| { 38400, B38400 }, |
| { 19200, B19200 }, |
| { 9600, B9600 }, |
| { 4800, B4800 }, |
| { 2400, B2400 }, |
| { 1200, B1200 }, |
| { 0, B38400 } |
| }; |
| |
| /** |
| * uart_set_options - setup the serial console parameters |
| * @port: pointer to the serial ports uart_port structure |
| * @co: console pointer |
| * @baud: baud rate |
| * @parity: parity character - 'n' (none), 'o' (odd), 'e' (even) |
| * @bits: number of data bits |
| * @flow: flow control character - 'r' (rts) |
| */ |
| int |
| uart_set_options(struct uart_port *port, struct console *co, |
| int baud, int parity, int bits, int flow) |
| { |
| struct ktermios termios; |
| static struct ktermios dummy; |
| int i; |
| |
| /* |
| * Ensure that the serial console lock is initialised |
| * early. |
| */ |
| spin_lock_init(&port->lock); |
| lockdep_set_class(&port->lock, &port_lock_key); |
| |
| memset(&termios, 0, sizeof(struct ktermios)); |
| |
| termios.c_cflag = CREAD | HUPCL | CLOCAL; |
| |
| /* |
| * Construct a cflag setting. |
| */ |
| for (i = 0; baud_rates[i].rate; i++) |
| if (baud_rates[i].rate <= baud) |
| break; |
| |
| termios.c_cflag |= baud_rates[i].cflag; |
| |
| if (bits == 7) |
| termios.c_cflag |= CS7; |
| else |
| termios.c_cflag |= CS8; |
| |
| switch (parity) { |
| case 'o': case 'O': |
| termios.c_cflag |= PARODD; |
| /*fall through*/ |
| case 'e': case 'E': |
| termios.c_cflag |= PARENB; |
| break; |
| } |
| |
| if (flow == 'r') |
| termios.c_cflag |= CRTSCTS; |
| |
| /* |
| * some uarts on other side don't support no flow control. |
| * So we set * DTR in host uart to make them happy |
| */ |
| port->mctrl |= TIOCM_DTR; |
| |
| port->ops->set_termios(port, &termios, &dummy); |
| /* |
| * Allow the setting of the UART parameters with a NULL console |
| * too: |
| */ |
| if (co) |
| co->cflag = termios.c_cflag; |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(uart_set_options); |
| #endif /* CONFIG_SERIAL_CORE_CONSOLE */ |
| |
| static void uart_change_pm(struct uart_state *state, int pm_state) |
| { |
| struct uart_port *port = state->uart_port; |
| |
| if (state->pm_state != pm_state) { |
| if (port->ops->pm) |
| port->ops->pm(port, pm_state, state->pm_state); |
| state->pm_state = pm_state; |
| } |
| } |
| |
| struct uart_match { |
| struct uart_port *port; |
| struct uart_driver *driver; |
| }; |
| |
| static int serial_match_port(struct device *dev, void *data) |
| { |
| struct uart_match *match = data; |
| struct tty_driver *tty_drv = match->driver->tty_driver; |
| dev_t devt = MKDEV(tty_drv->major, tty_drv->minor_start) + |
| match->port->line; |
| |
| return dev->devt == devt; /* Actually, only one tty per port */ |
| } |
| |
| int uart_suspend_port(struct uart_driver *drv, struct uart_port *uport) |
| { |
| struct uart_state *state = drv->state + uport->line; |
| struct tty_port *port = &state->port; |
| struct device *tty_dev; |
| struct uart_match match = {uport, drv}; |
| |
| mutex_lock(&port->mutex); |
| |
| tty_dev = device_find_child(uport->dev, &match, serial_match_port); |
| if (device_may_wakeup(tty_dev)) { |
| if (!enable_irq_wake(uport->irq)) |
| uport->irq_wake = 1; |
| put_device(tty_dev); |
| mutex_unlock(&port->mutex); |
| return 0; |
| } |
| if (console_suspend_enabled || !uart_console(uport)) |
| uport->suspended = 1; |
| |
| if (port->flags & ASYNC_INITIALIZED) { |
| const struct uart_ops *ops = uport->ops; |
| int tries; |
| |
| if (console_suspend_enabled || !uart_console(uport)) { |
| set_bit(ASYNCB_SUSPENDED, &port->flags); |
| clear_bit(ASYNCB_INITIALIZED, &port->flags); |
| |
| spin_lock_irq(&uport->lock); |
| ops->stop_tx(uport); |
| ops->set_mctrl(uport, 0); |
| ops->stop_rx(uport); |
| spin_unlock_irq(&uport->lock); |
| } |
| |
| /* |
| * Wait for the transmitter to empty. |
| */ |
| for (tries = 3; !ops->tx_empty(uport) && tries; tries--) |
| msleep(10); |
| if (!tries) |
| printk(KERN_ERR "%s%s%s%d: Unable to drain " |
| "transmitter\n", |
| uport->dev ? dev_name(uport->dev) : "", |
| uport->dev ? ": " : "", |
| drv->dev_name, |
| drv->tty_driver->name_base + uport->line); |
| |
| if (console_suspend_enabled || !uart_console(uport)) |
| ops->shutdown(uport); |
| } |
| |
| /* |
| * Disable the console device before suspending. |
| */ |
| if (console_suspend_enabled && uart_console(uport)) |
| console_stop(uport->cons); |
| |
| if (console_suspend_enabled || !uart_console(uport)) |
| uart_change_pm(state, 3); |
| |
| mutex_unlock(&port->mutex); |
| |
| return 0; |
| } |
| |
| int uart_resume_port(struct uart_driver *drv, struct uart_port *uport) |
| { |
| struct uart_state *state = drv->state + uport->line; |
| struct tty_port *port = &state->port; |
| struct device *tty_dev; |
| struct uart_match match = {uport, drv}; |
| struct ktermios termios; |
| |
| mutex_lock(&port->mutex); |
| |
| tty_dev = device_find_child(uport->dev, &match, serial_match_port); |
| if (!uport->suspended && device_may_wakeup(tty_dev)) { |
| if (uport->irq_wake) { |
| disable_irq_wake(uport->irq); |
| uport->irq_wake = 0; |
| } |
| mutex_unlock(&port->mutex); |
| return 0; |
| } |
| uport->suspended = 0; |
| |
| /* |
| * Re-enable the console device after suspending. |
| */ |
| if (uart_console(uport)) { |
| /* |
| * First try to use the console cflag setting. |
| */ |
| memset(&termios, 0, sizeof(struct ktermios)); |
| termios.c_cflag = uport->cons->cflag; |
| |
| /* |
| * If that's unset, use the tty termios setting. |
| */ |
| if (port->tty && port->tty->termios && termios.c_cflag == 0) |
| termios = *(port->tty->termios); |
| |
| if (console_suspend_enabled) |
| uart_change_pm(state, 0); |
| uport->ops->set_termios(uport, &termios, NULL); |
| if (console_suspend_enabled) |
| console_start(uport->cons); |
| } |
| |
| if (port->flags & ASYNC_SUSPENDED) { |
| const struct uart_ops *ops = uport->ops; |
| int ret; |
| |
| uart_change_pm(state, 0); |
| spin_lock_irq(&uport->lock); |
| ops->set_mctrl(uport, 0); |
| spin_unlock_irq(&uport->lock); |
| if (console_suspend_enabled || !uart_console(uport)) { |
| /* Protected by port mutex for now */ |
| struct tty_struct *tty = port->tty; |
| ret = ops->startup(uport); |
| if (ret == 0) { |
| if (tty) |
| uart_change_speed(tty, state, NULL); |
| spin_lock_irq(&uport->lock); |
| ops->set_mctrl(uport, uport->mctrl); |
| ops->start_tx(uport); |
| spin_unlock_irq(&uport->lock); |
| set_bit(ASYNCB_INITIALIZED, &port->flags); |
| } else { |
| /* |
| * Failed to resume - maybe hardware went away? |
| * Clear the "initialized" flag so we won't try |
| * to call the low level drivers shutdown method. |
| */ |
| uart_shutdown(tty, state); |
| } |
| } |
| |
| clear_bit(ASYNCB_SUSPENDED, &port->flags); |
| } |
| |
| mutex_unlock(&port->mutex); |
| |
| return 0; |
| } |
| |
| static inline void |
| uart_report_port(struct uart_driver *drv, struct uart_port *port) |
| { |
| char address[64]; |
| |
| switch (port->iotype) { |
| case UPIO_PORT: |
| snprintf(address, sizeof(address), "I/O 0x%lx", port->iobase); |
| break; |
| case UPIO_HUB6: |
| snprintf(address, sizeof(address), |
| "I/O 0x%lx offset 0x%x", port->iobase, port->hub6); |
| break; |
| case UPIO_MEM: |
| case UPIO_MEM32: |
| case UPIO_AU: |
| case UPIO_TSI: |
| case UPIO_DWAPB: |
| case UPIO_DWAPB32: |
| snprintf(address, sizeof(address), |
| "MMIO 0x%llx", (unsigned long long)port->mapbase); |
| break; |
| default: |
| strlcpy(address, "*unknown*", sizeof(address)); |
| break; |
| } |
| |
| printk(KERN_INFO "%s%s%s%d at %s (irq = %d) is a %s\n", |
| port->dev ? dev_name(port->dev) : "", |
| port->dev ? ": " : "", |
| drv->dev_name, |
| drv->tty_driver->name_base + port->line, |
| address, port->irq, uart_type(port)); |
| } |
| |
| static void |
| uart_configure_port(struct uart_driver *drv, struct uart_state *state, |
| struct uart_port *port) |
| { |
| unsigned int flags; |
| |
| /* |
| * If there isn't a port here, don't do anything further. |
| */ |
| if (!port->iobase && !port->mapbase && !port->membase) |
| return; |
| |
| /* |
| * Now do the auto configuration stuff. Note that config_port |
| * is expected to claim the resources and map the port for us. |
| */ |
| flags = 0; |
| if (port->flags & UPF_AUTO_IRQ) |
| flags |= UART_CONFIG_IRQ; |
| if (port->flags & UPF_BOOT_AUTOCONF) { |
| if (!(port->flags & UPF_FIXED_TYPE)) { |
| port->type = PORT_UNKNOWN; |
| flags |= UART_CONFIG_TYPE; |
| } |
| port->ops->config_port(port, flags); |
| } |
| |
| if (port->type != PORT_UNKNOWN) { |
| unsigned long flags; |
| |
| uart_report_port(drv, port); |
| |
| /* Power up port for set_mctrl() */ |
| uart_change_pm(state, 0); |
| |
| /* |
| * Ensure that the modem control lines are de-activated. |
| * keep the DTR setting that is set in uart_set_options() |
| * We probably don't need a spinlock around this, but |
| */ |
| spin_lock_irqsave(&port->lock, flags); |
| port->ops->set_mctrl(port, port->mctrl & TIOCM_DTR); |
| spin_unlock_irqrestore(&port->lock, flags); |
| |
| /* |
| * If this driver supports console, and it hasn't been |
| * successfully registered yet, try to re-register it. |
| * It may be that the port was not available. |
| */ |
| if (port->cons && !(port->cons->flags & CON_ENABLED)) |
| register_console(port->cons); |
| |
| /* |
| * Power down all ports by default, except the |
| * console if we have one. |
| */ |
| if (!uart_console(port)) |
| uart_change_pm(state, 3); |
| } |
| } |
| |
| #ifdef CONFIG_CONSOLE_POLL |
| |
| static int uart_poll_init(struct tty_driver *driver, int line, char *options) |
| { |
| struct uart_driver *drv = driver->driver_state; |
| struct uart_state *state = drv->state + line; |
| struct uart_port *port; |
| int baud = 9600; |
| int bits = 8; |
| int parity = 'n'; |
| int flow = 'n'; |
| |
| if (!state || !state->uart_port) |
| return -1; |
| |
| port = state->uart_port; |
| if (!(port->ops->poll_get_char && port->ops->poll_put_char)) |
| return -1; |
| |
| if (options) { |
| uart_parse_options(options, &baud, &parity, &bits, &flow); |
| return uart_set_options(port, NULL, baud, parity, bits, flow); |
| } |
| |
| return 0; |
| } |
| |
| static int uart_poll_get_char(struct tty_driver *driver, int line) |
| { |
| struct uart_driver *drv = driver->driver_state; |
| struct uart_state *state = drv->state + line; |
| struct uart_port *port; |
| |
| if (!state || !state->uart_port) |
| return -1; |
| |
| port = state->uart_port; |
| return port->ops->poll_get_char(port); |
| } |
| |
| static void uart_poll_put_char(struct tty_driver *driver, int line, char ch) |
| { |
| struct uart_driver *drv = driver->driver_state; |
| struct uart_state *state = drv->state + line; |
| struct uart_port *port; |
| |
| if (!state || !state->uart_port) |
| return; |
| |
| port = state->uart_port; |
| port->ops->poll_put_char(port, ch); |
| } |
| #endif |
| |
| static const struct tty_operations uart_ops = { |
| .open = uart_open, |
| .close = uart_close, |
| .write = uart_write, |
| .put_char = uart_put_char, |
| .flush_chars = uart_flush_chars, |
| .write_room = uart_write_room, |
| .chars_in_buffer= uart_chars_in_buffer, |
| .flush_buffer = uart_flush_buffer, |
| .ioctl = uart_ioctl, |
| .throttle = uart_throttle, |
| .unthrottle = uart_unthrottle, |
| .send_xchar = uart_send_xchar, |
| .set_termios = uart_set_termios, |
| .set_ldisc = uart_set_ldisc, |
| .stop = uart_stop, |
| .start = uart_start, |
| .hangup = uart_hangup, |
| .break_ctl = uart_break_ctl, |
| .wait_until_sent= uart_wait_until_sent, |
| #ifdef CONFIG_PROC_FS |
| .proc_fops = &uart_proc_fops, |
| #endif |
| .tiocmget = uart_tiocmget, |
| .tiocmset = uart_tiocmset, |
| .get_icount = uart_get_icount, |
| #ifdef CONFIG_CONSOLE_POLL |
| .poll_init = uart_poll_init, |
| .poll_get_char = uart_poll_get_char, |
| .poll_put_char = uart_poll_put_char, |
| #endif |
| }; |
| |
| static const struct tty_port_operations uart_port_ops = { |
| .carrier_raised = uart_carrier_raised, |
| .dtr_rts = uart_dtr_rts, |
| }; |
| |
| /** |
| * uart_register_driver - register a driver with the uart core layer |
| * @drv: low level driver structure |
| * |
| * Register a uart driver with the core driver. We in turn register |
| * with the tty layer, and initialise the core driver per-port state. |
| * |
| * We have a proc file in /proc/tty/driver which is named after the |
| * normal driver. |
| * |
| * drv->port should be NULL, and the per-port structures should be |
| * registered using uart_add_one_port after this call has succeeded. |
| */ |
| int uart_register_driver(struct uart_driver *drv) |
| { |
| struct tty_driver *normal; |
| int i, retval; |
| |
| BUG_ON(drv->state); |
| |
| /* |
| * Maybe we should be using a slab cache for this, especially if |
| * we have a large number of ports to handle. |
| */ |
| drv->state = kzalloc(sizeof(struct uart_state) * drv->nr, GFP_KERNEL); |
| if (!drv->state) |
| goto out; |
| |
| normal = alloc_tty_driver(drv->nr); |
| if (!normal) |
| goto out_kfree; |
| |
| drv->tty_driver = normal; |
| |
| normal->owner = drv->owner; |
| normal->driver_name = drv->driver_name; |
| normal->name = drv->dev_name; |
| normal->major = drv->major; |
| normal->minor_start = drv->minor; |
| normal->type = TTY_DRIVER_TYPE_SERIAL; |
| normal->subtype = SERIAL_TYPE_NORMAL; |
| normal->init_termios = tty_std_termios; |
| normal->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL; |
| normal->init_termios.c_ispeed = normal->init_termios.c_ospeed = 9600; |
| normal->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV; |
| normal->driver_state = drv; |
| tty_set_operations(normal, &uart_ops); |
| |
| /* |
| * Initialise the UART state(s). |
| */ |
| for (i = 0; i < drv->nr; i++) { |
| struct uart_state *state = drv->state + i; |
| struct tty_port *port = &state->port; |
| |
| tty_port_init(port); |
| port->ops = &uart_port_ops; |
| port->close_delay = 500; /* .5 seconds */ |
| port->closing_wait = 30000; /* 30 seconds */ |
| tasklet_init(&state->tlet, uart_tasklet_action, |
| (unsigned long)state); |
| } |
| |
| retval = tty_register_driver(normal); |
| if (retval >= 0) |
| return retval; |
| |
| put_tty_driver(normal); |
| out_kfree: |
| kfree(drv->state); |
| out: |
| return -ENOMEM; |
| } |
| |
| /** |
| * uart_unregister_driver - remove a driver from the uart core layer |
| * @drv: low level driver structure |
| * |
| * Remove all references to a driver from the core driver. The low |
| * level driver must have removed all its ports via the |
| * uart_remove_one_port() if it registered them with uart_add_one_port(). |
| * (ie, drv->port == NULL) |
| */ |
| void uart_unregister_driver(struct uart_driver *drv) |
| { |
| struct tty_driver *p = drv->tty_driver; |
| tty_unregister_driver(p); |
| put_tty_driver(p); |
| kfree(drv->state); |
| drv->tty_driver = NULL; |
| } |
| |
| struct tty_driver *uart_console_device(struct console *co, int *index) |
| { |
| struct uart_driver *p = co->data; |
| *index = co->index; |
| return p->tty_driver; |
| } |
| |
| /** |
| * uart_add_one_port - attach a driver-defined port structure |
| * @drv: pointer to the uart low level driver structure for this port |
| * @uport: uart port structure to use for this port. |
| * |
| * This allows the driver to register its own uart_port structure |
| * with the core driver. The main purpose is to allow the low |
| * level uart drivers to expand uart_port, rather than having yet |
| * more levels of structures. |
| */ |
| int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport) |
| { |
| struct uart_state *state; |
| struct tty_port *port; |
| int ret = 0; |
| struct device *tty_dev; |
| |
| BUG_ON(in_interrupt()); |
| |
| if (uport->line >= drv->nr) |
| return -EINVAL; |
| |
| state = drv->state + uport->line; |
| port = &state->port; |
| |
| mutex_lock(&port_mutex); |
| mutex_lock(&port->mutex); |
| if (state->uart_port) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| state->uart_port = uport; |
| state->pm_state = -1; |
| |
| uport->cons = drv->cons; |
| uport->state = state; |
| |
| /* |
| * If this port is a console, then the spinlock is already |
| * initialised. |
| */ |
| if (!(uart_console(uport) && (uport->cons->flags & CON_ENABLED))) { |
| spin_lock_init(&uport->lock); |
| lockdep_set_class(&uport->lock, &port_lock_key); |
| } |
| |
| uart_configure_port(drv, state, uport); |
| |
| /* |
| * Register the port whether it's detected or not. This allows |
| * setserial to be used to alter this ports parameters. |
| */ |
| tty_dev = tty_register_device(drv->tty_driver, uport->line, uport->dev); |
| if (likely(!IS_ERR(tty_dev))) { |
| device_init_wakeup(tty_dev, 1); |
| device_set_wakeup_enable(tty_dev, 0); |
| } else |
| printk(KERN_ERR "Cannot register tty device on line %d\n", |
| uport->line); |
| |
| /* |
| * Ensure UPF_DEAD is not set. |
| */ |
| uport->flags &= ~UPF_DEAD; |
| |
| out: |
| mutex_unlock(&port->mutex); |
| mutex_unlock(&port_mutex); |
| |
| return ret; |
| } |
| |
| /** |
| * uart_remove_one_port - detach a driver defined port structure |
| * @drv: pointer to the uart low level driver structure for this port |
| * @uport: uart port structure for this port |
| * |
| * This unhooks (and hangs up) the specified port structure from the |
| * core driver. No further calls will be made to the low-level code |
| * for this port. |
| */ |
| int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport) |
| { |
| struct uart_state *state = drv->state + uport->line; |
| struct tty_port *port = &state->port; |
| |
| BUG_ON(in_interrupt()); |
| |
| if (state->uart_port != uport) |
| printk(KERN_ALERT "Removing wrong port: %p != %p\n", |
| state->uart_port, uport); |
| |
| mutex_lock(&port_mutex); |
| |
| /* |
| * Mark the port "dead" - this prevents any opens from |
| * succeeding while we shut down the port. |
| */ |
| mutex_lock(&port->mutex); |
| uport->flags |= UPF_DEAD; |
| mutex_unlock(&port->mutex); |
| |
| /* |
| * Remove the devices from the tty layer |
| */ |
| tty_unregister_device(drv->tty_driver, uport->line); |
| |
| if (port->tty) |
| tty_vhangup(port->tty); |
| |
| /* |
| * Free the port IO and memory resources, if any. |
| */ |
| if (uport->type != PORT_UNKNOWN) |
| uport->ops->release_port(uport); |
| |
| /* |
| * Indicate that there isn't a port here anymore. |
| */ |
| uport->type = PORT_UNKNOWN; |
| |
| /* |
| * Kill the tasklet, and free resources. |
| */ |
| tasklet_kill(&state->tlet); |
| |
| state->uart_port = NULL; |
| mutex_unlock(&port_mutex); |
| |
| return 0; |
| } |
| |
| /* |
| * Are the two ports equivalent? |
| */ |
| int uart_match_port(struct uart_port *port1, struct uart_port *port2) |
| { |
| if (port1->iotype != port2->iotype) |
| return 0; |
| |
| switch (port1->iotype) { |
| case UPIO_PORT: |
| return (port1->iobase == port2->iobase); |
| case UPIO_HUB6: |
| return (port1->iobase == port2->iobase) && |
| (port1->hub6 == port2->hub6); |
| case UPIO_MEM: |
| case UPIO_MEM32: |
| case UPIO_AU: |
| case UPIO_TSI: |
| case UPIO_DWAPB: |
| case UPIO_DWAPB32: |
| return (port1->mapbase == port2->mapbase); |
| } |
| return 0; |
| } |
| EXPORT_SYMBOL(uart_match_port); |
| |
| EXPORT_SYMBOL(uart_write_wakeup); |
| EXPORT_SYMBOL(uart_register_driver); |
| EXPORT_SYMBOL(uart_unregister_driver); |
| EXPORT_SYMBOL(uart_suspend_port); |
| EXPORT_SYMBOL(uart_resume_port); |
| EXPORT_SYMBOL(uart_add_one_port); |
| EXPORT_SYMBOL(uart_remove_one_port); |
| |
| MODULE_DESCRIPTION("Serial driver core"); |
| MODULE_LICENSE("GPL"); |