Thread (5 messages) 5 messages, 3 authors, 2016-10-28

Re: [PATCH 2/2] serial: 8250_dw: Add support for IrDA SIR mode

From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Date: 2016-10-27 16:56:20
Also in: lkml

On Thu, 2016-10-27 at 17:38 +0100, Ed Blake wrote:
Add a set_ldisc function to enable/disable IrDA SIR mode according to
the new line discipline.
Thanks for the patch.

Consider that not all implementations based on 8250_dw support IRDA
feature. I suppose you need to read capability register bits 6 and 7,
set flag and then based on the value accept or reject IRDA mode.

P.S. Use -n when prepare patches to link them if you consider them
dependent.
quoted hunk ↗ jump to hunk
Signed-off-by: Ed Blake <redacted>
---
 drivers/tty/serial/8250/8250_dw.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
diff --git a/drivers/tty/serial/8250/8250_dw.c
b/drivers/tty/serial/8250/8250_dw.c
index 459d726..7dd5369 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 +256,20 @@ 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)
+{
+	unsigned int mcr = p->serial_in(p, UART_MCR);
+
+	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
@@ -392,6 +408,7 @@ 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)
-- 
Andy Shevchenko [off-list ref]
Intel Finland Oy
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