summaryrefslogtreecommitdiff
path: root/drivers/tty/serial/8250.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/tty/serial/8250.c')
-rw-r--r--drivers/tty/serial/8250.c98
1 files changed, 35 insertions, 63 deletions
diff --git a/drivers/tty/serial/8250.c b/drivers/tty/serial/8250.c
index eeadf1b8e093..9f50c4e3c2be 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);
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-08 06:48:15 +0300