diff options
| author |   Vineet Gupta <Vineet.Gupta1@synopsys.com> | 2013-08-01 21:49:19 -0700 |
|---|---|---|
| committer |   Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-08-02 11:54:12 +0800 |
| commit | 5284eba7b37dfeffe75bfdf81a13e9efebe0480a (patch) | |
| tree | 488245e42b7e58d5e813cfd3de6f56c04c53c8a1 /drivers/tty/serial/arc_uart.c | |
| parent | tty: Only hangup once (diff) | |
| download | linux-dev-5284eba7b37dfeffe75bfdf81a13e9efebe0480a.tar.xz linux-dev-5284eba7b37dfeffe75bfdf81a13e9efebe0480a.zip | |
serial/arc-uart: Handle Rx Error Interrupts w/o any data
Currently, Rx error handling only triggers if there is some Rx data.
Fix that by checking for error - before the data handling.
Reported-by: Mischa Jonker <mjonker@synopsys.com>
Tested-by: Mischa Jonker <mjonker@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/arc_uart.c')
| -rw-r--r-- | drivers/tty/serial/arc_uart.c | 26 |
1 files changed, 16 insertions, 10 deletions
diff --git a/drivers/tty/serial/arc_uart.c b/drivers/tty/serial/arc_uart.c index 2f195f0d7a11..e296c892df61 100644 --- a/drivers/tty/serial/arc_uart.c +++ b/drivers/tty/serial/arc_uart.c @@ -209,9 +209,9 @@ static void arc_serial_start_tx(struct uart_port *port) arc_serial_tx_chars(uart); } -static void arc_serial_rx_chars(struct arc_uart_port *uart) +static void arc_serial_rx_chars(struct arc_uart_port *uart, unsigned int status) { - unsigned int status, ch, flg = 0; + unsigned int ch, flg = 0; /* * UART has 4 deep RX-FIFO. Driver's recongnition of this fact @@ -222,11 +222,11 @@ static void arc_serial_rx_chars(struct arc_uart_port *uart) * before RX-EMPTY=0, implies some sort of buffering going on in the * controller, which is indeed the Rx-FIFO. */ - while (!((status = UART_GET_STATUS(uart)) & RXEMPTY)) { - - ch = UART_GET_DATA(uart); - uart->port.icount.rx++; - + do { + /* + * This could be an Rx Intr for err (no data), + * so check err and clear that Intr first + */ if (unlikely(status & (RXOERR | RXFERR))) { if (status & RXOERR) { uart->port.icount.overrun++; @@ -242,6 +242,12 @@ static void arc_serial_rx_chars(struct arc_uart_port *uart) } else flg = TTY_NORMAL; + if (status & RXEMPTY) + continue; + + ch = UART_GET_DATA(uart); + uart->port.icount.rx++; + if (unlikely(uart_handle_sysrq_char(&uart->port, ch))) goto done; @@ -249,7 +255,7 @@ static void arc_serial_rx_chars(struct arc_uart_port *uart) done: tty_flip_buffer_push(&uart->port.state->port); - } + } while (!((status = UART_GET_STATUS(uart)) & RXEMPTY)); } /* @@ -292,11 +298,11 @@ static irqreturn_t arc_serial_isr(int irq, void *dev_id) * notifications from the UART Controller. * To demultiplex between the two, we check the relevant bits */ - if ((status & RXIENB) && !(status & RXEMPTY)) { + if (status & RXIENB) { /* already in ISR, no need of xx_irqsave */ spin_lock(&uart->port.lock); - arc_serial_rx_chars(uart); + arc_serial_rx_chars(uart, status); spin_unlock(&uart->port.lock); } |