serial: 8250_dw: Add support for IrDA SIR mode
Add a set_ldisc function to enable/disable IrDA SIR mode according to
the new line discipline, if IrDA SIR mode is supported by the hardware
configuration.
Signed-off-by: Ed Blake <ed.blake@imgtec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index 459d726..c89fafc 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -53,6 +53,8 @@
/* Helper for fifo size calculation */
#define DW_UART_CPR_FIFO_SIZE(a) (((a >> 16) & 0xff) * 16)
+/* DesignWare specific register fields */
+#define DW_UART_MCR_SIRE BIT(6)
struct dw8250_data {
u8 usr_reg;
@@ -254,6 +256,22 @@ static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios,
serial8250_do_set_termios(p, termios, old);
}
+static void dw8250_set_ldisc(struct uart_port *p, struct ktermios *termios)
+{
+ struct uart_8250_port *up = up_to_u8250p(p);
+ unsigned int mcr = p->serial_in(p, UART_MCR);
+
+ if (up->capabilities & UART_CAP_IRDA) {
+ if (termios->c_line == N_IRDA)
+ mcr |= DW_UART_MCR_SIRE;
+ else
+ mcr &= ~DW_UART_MCR_SIRE;
+
+ p->serial_out(p, UART_MCR, mcr);
+ }
+ serial8250_do_set_ldisc(p, termios);
+}
+
/*
* dw8250_fallback_dma_filter will prevent the UART from getting just any free
* channel on platforms that have DMA engines, but don't have any channels
@@ -357,6 +375,9 @@ static void dw8250_setup_port(struct uart_port *p)
if (reg & DW_UART_CPR_AFCE_MODE)
up->capabilities |= UART_CAP_AFE;
+
+ if (reg & DW_UART_CPR_SIR_MODE)
+ up->capabilities |= UART_CAP_IRDA;
}
static int dw8250_probe(struct platform_device *pdev)
@@ -392,6 +413,7 @@ static int dw8250_probe(struct platform_device *pdev)
p->iotype = UPIO_MEM;
p->serial_in = dw8250_serial_in;
p->serial_out = dw8250_serial_out;
+ p->set_ldisc = dw8250_set_ldisc;
p->membase = devm_ioremap(dev, regs->start, resource_size(regs));
if (!p->membase)
