OMAP/serial: Add support for driving a GPIO as DTR.
OMAP hardware doesn't provide a phyisical DTR line, but
some configurations may need a DTR line which tracks whether
the device is open or not.
So allow a gpio to be configured as the DTR line.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index d3cda0c..aa603f2 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -39,6 +39,7 @@
#include <linux/irq.h>
#include <linux/pm_runtime.h>
#include <linux/of.h>
+#include <linux/gpio.h>
#include <plat/dma.h>
#include <plat/dmtimer.h>
@@ -507,6 +508,16 @@
up->mcr |= mcr;
serial_out(up, UART_MCR, up->mcr);
pm_runtime_put(&up->pdev->dev);
+
+ if (gpio_is_valid(up->DTR_gpio) &&
+ !!(mctrl & TIOCM_DTR) != up->DTR_active) {
+ up->DTR_active = !up->DTR_active;
+ if (gpio_cansleep(up->DTR_gpio))
+ schedule_work(&up->qos_work);
+ else
+ gpio_set_value(up->DTR_gpio,
+ up->DTR_active != up->DTR_inverted);
+ }
}
static void serial_omap_break_ctl(struct uart_port *port, int break_state)
@@ -715,6 +726,9 @@
qos_work);
pm_qos_update_request(&up->pm_qos_request, up->latency);
+ if (gpio_is_valid(up->DTR_gpio))
+ gpio_set_value_cansleep(up->DTR_gpio,
+ up->DTR_active != up->DTR_inverted);
}
static void
@@ -1435,7 +1449,7 @@
struct uart_omap_port *up;
struct resource *mem, *irq, *dma_tx, *dma_rx;
struct omap_uart_port_info *omap_up_info = pdev->dev.platform_data;
- int ret = -ENOSPC;
+ int ret;
if (pdev->dev.of_node)
omap_up_info = of_get_uart_port_info(&pdev->dev);
@@ -1466,10 +1480,29 @@
if (!dma_tx)
return -ENXIO;
+ if (gpio_is_valid(omap_up_info->DTR_gpio) &&
+ omap_up_info->DTR_present) {
+ ret = gpio_request(omap_up_info->DTR_gpio, "omap-serial");
+ if (ret < 0)
+ return ret;
+ ret = gpio_direction_output(omap_up_info->DTR_gpio,
+ omap_up_info->DTR_inverted);
+ if (ret < 0)
+ return ret;
+ }
+
up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
if (!up)
return -ENOMEM;
+ if (gpio_is_valid(omap_up_info->DTR_gpio) &&
+ omap_up_info->DTR_present) {
+ up->DTR_gpio = omap_up_info->DTR_gpio;
+ up->DTR_inverted = omap_up_info->DTR_inverted;
+ } else
+ up->DTR_gpio = -EINVAL;
+ up->DTR_active = 0;
+
up->pdev = pdev;
up->port.dev = &pdev->dev;
up->port.type = PORT_OMAP;