tty: ar933x_uart: use the clk API to get the uart clock
The AR933x UARTs are only used on the Atheros AR933x
SoCs. The base clock frequency of the UART is passed
to the driver via platform data. The SoC support code
implements the generic clock API, and the clock rate
can be retrieved via that.
Update the code to get the clock rate via the generic
clock API instead of using the platform data.
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/ar933x_uart.c b/drivers/tty/serial/ar933x_uart.c
index 78be13a..1052ee0 100644
--- a/drivers/tty/serial/ar933x_uart.c
+++ b/drivers/tty/serial/ar933x_uart.c
@@ -24,11 +24,11 @@
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/irq.h>
+#include <linux/clk.h>
#include <asm/div64.h>
#include <asm/mach-ath79/ar933x_uart.h>
-#include <asm/mach-ath79/ar933x_uart_platform.h>
#define DRIVER_NAME "ar933x-uart"
@@ -47,6 +47,7 @@
unsigned int ier; /* shadow Interrupt Enable Register */
unsigned int min_baud;
unsigned int max_baud;
+ struct clk *clk;
};
static inline unsigned int ar933x_uart_read(struct ar933x_uart_port *up,
@@ -622,7 +623,6 @@
static int ar933x_uart_probe(struct platform_device *pdev)
{
- struct ar933x_uart_platform_data *pdata;
struct ar933x_uart_port *up;
struct uart_port *port;
struct resource *mem_res;
@@ -631,10 +631,6 @@
int id;
int ret;
- pdata = dev_get_platdata(&pdev->dev);
- if (!pdata)
- return -EINVAL;
-
id = pdev->id;
if (id == -1)
id = 0;
@@ -653,6 +649,12 @@
if (!up)
return -ENOMEM;
+ up->clk = devm_clk_get(&pdev->dev, "uart");
+ if (IS_ERR(up->clk)) {
+ dev_err(&pdev->dev, "unable to get UART clock\n");
+ return PTR_ERR(up->clk);
+ }
+
port = &up->port;
mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -660,13 +662,22 @@
if (IS_ERR(port->membase))
return PTR_ERR(port->membase);
+ ret = clk_prepare_enable(up->clk);
+ if (ret)
+ return ret;
+
+ port->uartclk = clk_get_rate(up->clk);
+ if (!port->uartclk) {
+ ret = -EINVAL;
+ goto err_disable_clk;
+ }
+
port->mapbase = mem_res->start;
port->line = id;
port->irq = irq_res->start;
port->dev = &pdev->dev;
port->type = PORT_AR933X;
port->iotype = UPIO_MEM32;
- port->uartclk = pdata->uartclk;
port->regshift = 2;
port->fifosize = AR933X_UART_FIFO_SIZE;
@@ -682,10 +693,14 @@
ret = uart_add_one_port(&ar933x_uart_driver, &up->port);
if (ret)
- return ret;
+ goto err_disable_clk;
platform_set_drvdata(pdev, up);
return 0;
+
+err_disable_clk:
+ clk_disable_unprepare(up->clk);
+ return ret;
}
static int ar933x_uart_remove(struct platform_device *pdev)
@@ -694,8 +709,10 @@
up = platform_get_drvdata(pdev);
- if (up)
+ if (up) {
uart_remove_one_port(&ar933x_uart_driver, &up->port);
+ clk_disable_unprepare(up->clk);
+ }
return 0;
}