Currently this driver expects the clock-frequency attribute. This
patch allows getting clock-frequency through clk driver API
clk_get_rate() if clock-frequency attribute is not defined.
So in the device bindings for serial device, one can add clocks
phandle to refer to the clk device to get the rate.
Signed-off-by: Murali Karicheri <[email protected]>
diff --git a/drivers/tty/serial/of_serial.c b/drivers/tty/serial/of_serial.c
index 34e7187..6f64f02 100644
--- a/drivers/tty/serial/of_serial.c
+++ b/drivers/tty/serial/of_serial.c
@@ -21,8 +21,10 @@
#include <linux/of_serial.h>
#include <linux/of_platform.h>
#include <linux/nwpserial.h>
+#include <linux/clk.h>
struct of_serial_info {
+ struct clk *clk;
int type;
int line;
};
@@ -51,7 +53,8 @@ EXPORT_SYMBOL_GPL(tegra_serial_handle_break);
* Fill a struct uart_port for a given device node
*/
static int __devinit of_platform_serial_setup(struct platform_device *ofdev,
- int type, struct uart_port *port)
+ int type, struct uart_port *port,
+ struct of_serial_info *info)
{
struct resource resource;
struct device_node *np = ofdev->dev.of_node;
@@ -60,8 +63,17 @@ static int __devinit of_platform_serial_setup(struct
platform_device *ofdev,
memset(port, 0, sizeof *port);
if (of_property_read_u32(np, "clock-frequency", &clk)) {
- dev_warn(&ofdev->dev, "no clock-frequency property set\n");
- return -ENODEV;
+
+ /* Get clk rate through clk driver if present */
+ info->clk = clk_get(&ofdev->dev, NULL);
+ if (info->clk == NULL) {
+ dev_warn(&ofdev->dev,
+ "clk or clock-frequency not defined\n");
+ return -ENODEV;
+ }
+
+ clk_prepare_enable(info->clk);
+ clk = clk_get_rate(info->clk);
}
/* If current-speed was set, then try not to change it. */
if (of_property_read_u32(np, "current-speed", &spd) == 0)
@@ -70,7 +82,7 @@ static int __devinit of_platform_serial_setup(struct
platform_device *ofdev,
ret = of_address_to_resource(np, 0, &resource);
if (ret) {
dev_warn(&ofdev->dev, "invalid address\n");
- return ret;
+ goto out;
}
spin_lock_init(&port->lock);
@@ -97,7 +109,8 @@ static int __devinit of_platform_serial_setup(struct
platform_device *ofdev,
default:
dev_warn(&ofdev->dev, "unsupported reg-io-width (%d)\n",
prop);
- return -EINVAL;
+ ret = -EINVAL;
+ goto out;
}
}
@@ -111,6 +124,10 @@ static int __devinit of_platform_serial_setup(struct platform_device *ofdev,
port->handle_break = tegra_serial_handle_break;
return 0;
+out:
+ if (info->clk)
+ clk_disable_unprepare(info->clk);
+ return ret;
}
/*
@@ -137,7 +154,7 @@ static int __devinit of_platform_serial_probe(struct
platform_device *ofdev)
return -ENOMEM;
port_type = (unsigned long)match->data;
- ret = of_platform_serial_setup(ofdev, port_type, &port);
+ ret = of_platform_serial_setup(ofdev, port_type, &port, info);
if (ret)
goto out;
@@ -193,6 +210,9 @@ static int of_platform_serial_remove(struct platform_device *ofdev)
/* need to add code for these */
break;
}
+
+ if (info->clk)
+ clk_disable_unprepare(info->clk);
kfree(info);
return 0;
}
