diff options
Diffstat (limited to 'drivers/tty/serial/8250.c')
-rw-r--r-- | drivers/tty/serial/8250.c | 98 |
1 files changed, 35 insertions, 63 deletions
diff --git a/drivers/tty/serial/8250.c b/drivers/tty/serial/8250.c index eeadf1b..9f50c4e 100644 --- a/drivers/tty/serial/8250.c +++ b/drivers/tty/serial/8250.c @@ -129,32 +129,6 @@ static unsigned long probe_rsa[PORT_RSA_MAX]; static unsigned int probe_rsa_count; #endif /* CONFIG_SERIAL_8250_RSA */ -struct uart_8250_port { - struct uart_port port; - struct timer_list timer; /* "no irq" timer */ - struct list_head list; /* ports on this IRQ */ - unsigned short capabilities; /* port capabilities */ - unsigned short bugs; /* port bugs */ - unsigned int tx_loadsz; /* transmit fifo load size */ - unsigned char acr; - unsigned char ier; - unsigned char lcr; - unsigned char mcr; - unsigned char mcr_mask; /* mask of user bits */ - unsigned char mcr_force; /* mask of forced bits */ - unsigned char cur_iotype; /* Running I/O type */ - - /* - * Some bits in registers are cleared on a read, so they must - * be saved whenever the register is read but the bits will not - * be immediately processed. - */ -#define LSR_SAVE_FLAGS UART_LSR_BRK_ERROR_BITS - unsigned char lsr_saved_flags; -#define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA - unsigned char msr_saved_flags; -}; - struct irq_info { struct hlist_node node; int irq; @@ -1326,8 +1300,6 @@ static void serial8250_stop_tx(struct uart_port *port) } } -static void transmit_chars(struct uart_8250_port *up); - static void serial8250_start_tx(struct uart_port *port) { struct uart_8250_port *up = @@ -1344,7 +1316,7 @@ static void serial8250_start_tx(struct uart_port *port) if ((up->port.type == PORT_RM9000) ? (lsr & UART_LSR_THRE) : (lsr & UART_LSR_TEMT)) - transmit_chars(up); + serial8250_tx_chars(up); } } @@ -1401,11 +1373,16 @@ static void clear_rx_fifo(struct uart_8250_port *up) } while (1); } -static void -receive_chars(struct uart_8250_port *up, unsigned int *status) +/* + * serial8250_rx_chars: processes according to the passed in LSR + * value, and returns the remaining LSR bits not handled + * by this Rx routine. + */ +unsigned char +serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr) { struct tty_struct *tty = up->port.state->port.tty; - unsigned char ch, lsr = *status; + unsigned char ch; int max_count = 256; char flag; @@ -1481,10 +1458,11 @@ ignore_char: spin_unlock(&up->port.lock); tty_flip_buffer_push(tty); spin_lock(&up->port.lock); - *status = lsr; + return lsr; } +EXPORT_SYMBOL_GPL(serial8250_rx_chars); -static void transmit_chars(struct uart_8250_port *up) +void serial8250_tx_chars(struct uart_8250_port *up) { struct circ_buf *xmit = &up->port.state->xmit; int count; @@ -1521,8 +1499,9 @@ static void transmit_chars(struct uart_8250_port *up) if (uart_circ_empty(xmit)) __stop_tx(up); } +EXPORT_SYMBOL_GPL(serial8250_tx_chars); -static unsigned int check_modem_status(struct uart_8250_port *up) +unsigned int serial8250_modem_status(struct uart_8250_port *up) { unsigned int status = serial_in(up, UART_MSR); @@ -1544,14 +1523,20 @@ static unsigned int check_modem_status(struct uart_8250_port *up) return status; } +EXPORT_SYMBOL_GPL(serial8250_modem_status); /* * This handles the interrupt from one port. */ -static void serial8250_handle_port(struct uart_8250_port *up) +int serial8250_handle_irq(struct uart_port *port, unsigned int iir) { - unsigned int status; + unsigned char status; unsigned long flags; + struct uart_8250_port *up = + container_of(port, struct uart_8250_port, port); + + if (iir & UART_IIR_NO_INT) + return 0; spin_lock_irqsave(&up->port.lock, flags); @@ -1560,25 +1545,13 @@ static void serial8250_handle_port(struct uart_8250_port *up) DEBUG_INTR("status = %x...", status); if (status & (UART_LSR_DR | UART_LSR_BI)) - receive_chars(up, &status); - check_modem_status(up); + status = serial8250_rx_chars(up, status); + serial8250_modem_status(up); if (status & UART_LSR_THRE) - transmit_chars(up); + serial8250_tx_chars(up); spin_unlock_irqrestore(&up->port.lock, flags); -} - -int serial8250_handle_irq(struct uart_port *port, unsigned int iir) -{ - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); - - if (!(iir & UART_IIR_NO_INT)) { - serial8250_handle_port(up); - return 1; - } - - return 0; + return 1; } EXPORT_SYMBOL_GPL(serial8250_handle_irq); @@ -1619,11 +1592,13 @@ static irqreturn_t serial8250_interrupt(int irq, void *dev_id) do { struct uart_8250_port *up; struct uart_port *port; + bool skip; up = list_entry(l, struct uart_8250_port, list); port = &up->port; + skip = pass_counter && up->port.flags & UPF_IIR_ONCE; - if (port->handle_irq(port)) { + if (!skip && port->handle_irq(port)) { handled = 1; end = NULL; } else if (end == NULL) @@ -1758,11 +1733,8 @@ static void serial_unlink_irq_chain(struct uart_8250_port *up) static void serial8250_timeout(unsigned long data) { struct uart_8250_port *up = (struct uart_8250_port *)data; - unsigned int iir; - iir = serial_in(up, UART_IIR); - if (!(iir & UART_IIR_NO_INT)) - serial8250_handle_port(up); + up->port.handle_irq(&up->port); mod_timer(&up->timer, jiffies + uart_poll_timeout(&up->port)); } @@ -1801,7 +1773,7 @@ static void serial8250_backup_timeout(unsigned long data) } if (!(iir & UART_IIR_NO_INT)) - transmit_chars(up); + serial8250_tx_chars(up); if (is_real_interrupt(up->port.irq)) serial_out(up, UART_IER, ier); @@ -1835,7 +1807,7 @@ static unsigned int serial8250_get_mctrl(struct uart_port *port) unsigned int status; unsigned int ret; - status = check_modem_status(up); + status = serial8250_modem_status(up); ret = 0; if (status & UART_MSR_DCD) @@ -2000,7 +1972,7 @@ static int serial8250_startup(struct uart_port *port) serial_outp(up, UART_IER, 0); serial_outp(up, UART_LCR, 0); serial_icr_write(up, UART_CSR, 0); /* Reset the UART */ - serial_outp(up, UART_LCR, 0xBF); + serial_outp(up, UART_LCR, UART_LCR_CONF_MODE_B); serial_outp(up, UART_EFR, UART_EFR_ECB); serial_outp(up, UART_LCR, 0); } @@ -2848,7 +2820,7 @@ serial8250_console_write(struct console *co, const char *s, unsigned int count) local_irq_save(flags); if (up->port.sysrq) { - /* serial8250_handle_port() already took the lock */ + /* serial8250_handle_irq() already took the lock */ locked = 0; } else if (oops_in_progress) { locked = spin_trylock(&up->port.lock); @@ -2882,7 +2854,7 @@ serial8250_console_write(struct console *co, const char *s, unsigned int count) * while processing with interrupts off. */ if (up->msr_saved_flags) - check_modem_status(up); + serial8250_modem_status(up); if (locked) spin_unlock(&up->port.lock); |