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authorGabor Juhos <juhosg@openwrt.org>2013-08-28 10:09:28 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-08-28 16:00:42 -0700
commit15ef17f622033455dcf03ae96256e474073a7b11 (patch)
treef3b0b6f88fffa9e9be3395d7b4d655767a608194 /drivers
parenta416bfa2a6b4e00a7bc69641b8fc2414873a5fd9 (diff)
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>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/tty/serial/Kconfig2
-rw-r--r--drivers/tty/serial/ar933x_uart.c35
2 files changed, 27 insertions, 10 deletions
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index f13624807d12..3c598e3e7156 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -1402,7 +1402,7 @@ config SERIAL_XILINX_PS_UART_CONSOLE
config SERIAL_AR933X
bool "AR933X serial port support"
- depends on SOC_AR933X
+ depends on HAVE_CLK && SOC_AR933X
select SERIAL_CORE
help
If you have an Atheros AR933X SOC based board and want to use the
diff --git a/drivers/tty/serial/ar933x_uart.c b/drivers/tty/serial/ar933x_uart.c
index 78be13ac1a95..1052ee0383e0 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 @@ struct ar933x_uart_port {
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 struct uart_driver ar933x_uart_driver = {
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 @@ static int ar933x_uart_probe(struct platform_device *pdev)
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 @@ static int ar933x_uart_probe(struct platform_device *pdev)
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 @@ static int ar933x_uart_probe(struct platform_device *pdev)
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 @@ static int ar933x_uart_probe(struct platform_device *pdev)
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 @@ static int ar933x_uart_remove(struct platform_device *pdev)
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;
}