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serial: clean up parameter passing for 8250 Rx IRQ handling 

The receive_chars() was taking a pointer to a passed in LSR value
in status and knocking off bits as it processed them.  But since
receive_chars isn't returning a value, we can instead pass in
a normal non-pointer value for LSR, and simply return the
residual (unprocessed) LSR once it is done.

The value in this cleanup, is that it clarifies the API of the
receive_chars prior to exporting it to other 8250-like drivers
for shared usage.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Paul Gortmaker 2011-12-04 18:42:19 -05:00 committed by Greg Kroah-Hartman
parent 850624c15d
commit 0690f41fdd
1 changed files with 11 additions and 6 deletions
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17
drivers/tty/serial/8250.c
View File

@ -1375,11 +1375,16 @@ static void clear_rx_fifo(struct uart_8250_port *up)
} while (1);
}
static void
receive_chars(struct uart_8250_port *up, unsigned int *status)
/*
* receive_chars: processes according to the passed in LSR
* value, and returns the remaining LSR bits not handled
* by this Rx routine.
*/
static unsigned char
receive_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;
@ -1455,7 +1460,7 @@ ignore_char:
spin_unlock(&up->port.lock);
tty_flip_buffer_push(tty);
spin_lock(&up->port.lock);
*status = lsr;
return lsr;
}
static void transmit_chars(struct uart_8250_port *up)
@ -1524,7 +1529,7 @@ static unsigned int check_modem_status(struct uart_8250_port *up)
*/
static void serial8250_handle_port(struct uart_8250_port *up)
{
unsigned int status;
unsigned char status;
unsigned long flags;
spin_lock_irqsave(&up->port.lock, flags);
@ -1534,7 +1539,7 @@ 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);
status = receive_chars(up, status);
check_modem_status(up);
if (status & UART_LSR_THRE)
transmit_chars(up);