serial: sh-sci: Add overrun handling of SCIFA and SCIFB

SCIFA and SCIFB can detect the overrun, but it does not support.
This adds overrun handling of SCIFA and SCIFB.

Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 5b50c792ad5fd00e72ef86ed95a196d20e9ae06c..5bf997253a46452afad920fa5b8eb32ec1c9540c 100644 (file)
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -844,14 +844,32 @@ static int sci_handle_fifo_overrun(struct uart_port *port)
        struct tty_port *tport = &port->state->port;
        struct sci_port *s = to_sci_port(port);
        struct plat_sci_reg *reg;
-       int copied = 0;
+       int copied = 0, offset;
+       u16 status, bit;
 
-       reg = sci_getreg(port, SCLSR);
+       switch (port->type) {
+       case PORT_SCIF:
+       case PORT_HSCIF:
+               offset = SCLSR;
+               break;
+       case PORT_SCIFA:
+       case PORT_SCIFB:
+               offset = SCxSR;
+               break;
+       default:
+               return 0;
+       }
+
+       reg = sci_getreg(port, offset);
        if (!reg->size)
                return 0;
 
-       if ((serial_port_in(port, SCLSR) & (1 << s->overrun_bit))) {
-               serial_port_out(port, SCLSR, 0);
+       status = serial_port_in(port, offset);
+       bit = 1 << s->overrun_bit;
+
+       if (status & bit) {
+               status &= ~bit;
+               serial_port_out(port, offset, status);
 
                port->icount.overrun++;
 
@@ -996,16 +1014,24 @@ static inline unsigned long port_rx_irq_mask(struct uart_port *port)
 
 static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
 {
-       unsigned short ssr_status, scr_status, err_enabled;
-       unsigned short slr_status = 0;
+       unsigned short ssr_status, scr_status, err_enabled, orer_status = 0;
        struct uart_port *port = ptr;
        struct sci_port *s = to_sci_port(port);
        irqreturn_t ret = IRQ_NONE;
 
        ssr_status = serial_port_in(port, SCxSR);
        scr_status = serial_port_in(port, SCSCR);
-       if (port->type == PORT_SCIF || port->type == PORT_HSCIF)
-               slr_status = serial_port_in(port, SCLSR);
+       switch (port->type) {
+       case PORT_SCIF:
+       case PORT_HSCIF:
+               orer_status = serial_port_in(port, SCLSR);
+               break;
+       case PORT_SCIFA:
+       case PORT_SCIFB:
+               orer_status = ssr_status;
+               break;
+       }
+
        err_enabled = scr_status & port_rx_irq_mask(port);
 
        /* Tx Interrupt */
@@ -1033,10 +1059,8 @@ static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
                ret = sci_br_interrupt(irq, ptr);
 
        /* Overrun Interrupt */
-       if (port->type == PORT_SCIF || port->type == PORT_HSCIF) {
-               if (slr_status & 0x01)
-                       sci_handle_fifo_overrun(port);
-       }
+       if (orer_status & (1 << s->overrun_bit))
+               sci_handle_fifo_overrun(port);
 
        return ret;
 }