serial driver PMC MSP71xx

[linux-2.6-omap-h63xx.git] / drivers / serial / 8250.c

diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index 90621c3312bc662b4d97f178cd3f3cc14cc16d33..194362d9f5a33f7fbe269f34ff6824f188cc93c3 100644 (file)
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -308,6 +308,7 @@ static unsigned int serial_in(struct uart_8250_port *up, int offset)
                return inb(up->port.iobase + 1);
 
        case UPIO_MEM:
+       case UPIO_DWAPB:
                return readb(up->port.membase + offset);
 
        case UPIO_MEM32:
@@ -333,6 +334,8 @@ static unsigned int serial_in(struct uart_8250_port *up, int offset)
 static void
 serial_out(struct uart_8250_port *up, int offset, int value)
 {
+       /* Save the offset before it's remapped */
+       int save_offset = offset;
        offset = map_8250_out_reg(up, offset) << up->port.regshift;
 
        switch (up->port.iotype) {
@@ -359,6 +362,18 @@ serial_out(struct uart_8250_port *up, int offset, int value)
                        writeb(value, up->port.membase + offset);
                break;
 
+       case UPIO_DWAPB:
+               /* Save the LCR value so it can be re-written when a
+                * Busy Detect interrupt occurs. */
+               if (save_offset == UART_LCR)
+                       up->lcr = value;
+               writeb(value, up->port.membase + offset);
+               /* Read the IER to ensure any interrupt is cleared before
+                * returning from ISR. */
+               if (save_offset == UART_TX || save_offset == UART_IER)
+                       value = serial_in(up, UART_IER);
+               break;
+
        default:
                outb(value, up->port.iobase + offset);
        }
@@ -373,6 +388,7 @@ serial_out_sync(struct uart_8250_port *up, int offset, int value)
 #ifdef CONFIG_SERIAL_8250_AU1X00
        case UPIO_AU:
 #endif
+       case UPIO_DWAPB:
                serial_out(up, offset, value);
                serial_in(up, UART_LCR);        /* safe, no side-effects */
                break;
@@ -1388,6 +1404,19 @@ static irqreturn_t serial8250_interrupt(int irq, void *dev_id)
 
                        handled = 1;
 
+                       end = NULL;
+               } else if (up->port.iotype == UPIO_DWAPB &&
+                         (iir & UART_IIR_BUSY) == UART_IIR_BUSY) {
+                       /* The DesignWare APB UART has an Busy Detect (0x07)
+                        * interrupt meaning an LCR write attempt occured while the
+                        * UART was busy. The interrupt must be cleared by reading
+                        * the UART status register (USR) and the LCR re-written. */
+                       unsigned int status;
+                       status = *(volatile u32 *)up->port.private_data;
+                       serial_out(up, UART_LCR, up->lcr);
+
+                       handled = 1;
+
                        end = NULL;
                } else if (end == NULL)
                        end = l;
@@ -2090,6 +2119,7 @@ static int serial8250_request_std_resource(struct uart_8250_port *up)
        case UPIO_TSI:
        case UPIO_MEM32:
        case UPIO_MEM:
+       case UPIO_DWAPB:
                if (!up->port.mapbase)
                        break;
 
@@ -2127,6 +2157,7 @@ static void serial8250_release_std_resource(struct uart_8250_port *up)
        case UPIO_TSI:
        case UPIO_MEM32:
        case UPIO_MEM:
+       case UPIO_DWAPB:
                if (!up->port.mapbase)
                        break;