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Diffstat (limited to 'arch/arm/mach-s3c2410/clock.c')
-rw-r--r--arch/arm/mach-s3c2410/clock.c235
1 files changed, 110 insertions, 125 deletions
diff --git a/arch/arm/mach-s3c2410/clock.c b/arch/arm/mach-s3c2410/clock.c
index 82e8253b1fa0..af2f3d52b61b 100644
--- a/arch/arm/mach-s3c2410/clock.c
+++ b/arch/arm/mach-s3c2410/clock.c
@@ -34,16 +34,16 @@
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/sysdev.h>
-
#include <linux/interrupt.h>
#include <linux/ioport.h>
+#include <linux/clk.h>
+#include <linux/mutex.h>
#include <asm/hardware.h>
#include <asm/atomic.h>
#include <asm/irq.h>
#include <asm/io.h>
-#include <asm/hardware/clock.h>
#include <asm/arch/regs-clock.h>
#include "clock.h"
@@ -52,7 +52,7 @@
/* clock information */
static LIST_HEAD(clocks);
-static DECLARE_MUTEX(clocks_sem);
+static DEFINE_MUTEX(clocks_mutex);
/* old functions */
@@ -103,7 +103,7 @@ struct clk *clk_get(struct device *dev, const char *id)
else
idno = to_platform_device(dev)->id;
- down(&clocks_sem);
+ mutex_lock(&clocks_mutex);
list_for_each_entry(p, &clocks, list) {
if (p->id == idno &&
@@ -127,7 +127,7 @@ struct clk *clk_get(struct device *dev, const char *id)
}
}
- up(&clocks_sem);
+ mutex_unlock(&clocks_mutex);
return clk;
}
@@ -151,18 +151,6 @@ void clk_disable(struct clk *clk)
}
-int clk_use(struct clk *clk)
-{
- atomic_inc(&clk->used);
- return 0;
-}
-
-
-void clk_unuse(struct clk *clk)
-{
- atomic_dec(&clk->used);
-}
-
unsigned long clk_get_rate(struct clk *clk)
{
if (IS_ERR(clk))
@@ -196,8 +184,6 @@ EXPORT_SYMBOL(clk_get);
EXPORT_SYMBOL(clk_put);
EXPORT_SYMBOL(clk_enable);
EXPORT_SYMBOL(clk_disable);
-EXPORT_SYMBOL(clk_use);
-EXPORT_SYMBOL(clk_unuse);
EXPORT_SYMBOL(clk_get_rate);
EXPORT_SYMBOL(clk_round_rate);
EXPORT_SYMBOL(clk_set_rate);
@@ -268,100 +254,101 @@ struct clk s3c24xx_uclk = {
/* clock definitions */
static struct clk init_clocks[] = {
- { .name = "nand",
- .id = -1,
- .parent = &clk_h,
- .enable = s3c24xx_clkcon_enable,
- .ctrlbit = S3C2410_CLKCON_NAND
- },
- { .name = "lcd",
- .id = -1,
- .parent = &clk_h,
- .enable = s3c24xx_clkcon_enable,
- .ctrlbit = S3C2410_CLKCON_LCDC
- },
- { .name = "usb-host",
- .id = -1,
- .parent = &clk_h,
- .enable = s3c24xx_clkcon_enable,
- .ctrlbit = S3C2410_CLKCON_USBH
- },
- { .name = "usb-device",
- .id = -1,
- .parent = &clk_h,
- .enable = s3c24xx_clkcon_enable,
- .ctrlbit = S3C2410_CLKCON_USBD
- },
- { .name = "timers",
- .id = -1,
- .parent = &clk_p,
- .enable = s3c24xx_clkcon_enable,
- .ctrlbit = S3C2410_CLKCON_PWMT
- },
- { .name = "sdi",
- .id = -1,
- .parent = &clk_p,
- .enable = s3c24xx_clkcon_enable,
- .ctrlbit = S3C2410_CLKCON_SDI
- },
- { .name = "uart",
- .id = 0,
- .parent = &clk_p,
- .enable = s3c24xx_clkcon_enable,
- .ctrlbit = S3C2410_CLKCON_UART0
- },
- { .name = "uart",
- .id = 1,
- .parent = &clk_p,
- .enable = s3c24xx_clkcon_enable,
- .ctrlbit = S3C2410_CLKCON_UART1
- },
- { .name = "uart",
- .id = 2,
- .parent = &clk_p,
- .enable = s3c24xx_clkcon_enable,
- .ctrlbit = S3C2410_CLKCON_UART2
- },
- { .name = "gpio",
- .id = -1,
- .parent = &clk_p,
- .enable = s3c24xx_clkcon_enable,
- .ctrlbit = S3C2410_CLKCON_GPIO
- },
- { .name = "rtc",
- .id = -1,
- .parent = &clk_p,
- .enable = s3c24xx_clkcon_enable,
- .ctrlbit = S3C2410_CLKCON_RTC
- },
- { .name = "adc",
- .id = -1,
- .parent = &clk_p,
- .enable = s3c24xx_clkcon_enable,
- .ctrlbit = S3C2410_CLKCON_ADC
- },
- { .name = "i2c",
- .id = -1,
- .parent = &clk_p,
- .enable = s3c24xx_clkcon_enable,
- .ctrlbit = S3C2410_CLKCON_IIC
- },
- { .name = "iis",
- .id = -1,
- .parent = &clk_p,
- .enable = s3c24xx_clkcon_enable,
- .ctrlbit = S3C2410_CLKCON_IIS
- },
- { .name = "spi",
- .id = -1,
- .parent = &clk_p,
- .enable = s3c24xx_clkcon_enable,
- .ctrlbit = S3C2410_CLKCON_SPI
- },
- { .name = "watchdog",
- .id = -1,
- .parent = &clk_p,
- .ctrlbit = 0
+ {
+ .name = "nand",
+ .id = -1,
+ .parent = &clk_h,
+ .enable = s3c24xx_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_NAND,
+ }, {
+ .name = "lcd",
+ .id = -1,
+ .parent = &clk_h,
+ .enable = s3c24xx_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_LCDC,
+ }, {
+ .name = "usb-host",
+ .id = -1,
+ .parent = &clk_h,
+ .enable = s3c24xx_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_USBH,
+ }, {
+ .name = "usb-device",
+ .id = -1,
+ .parent = &clk_h,
+ .enable = s3c24xx_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_USBD,
+ }, {
+ .name = "timers",
+ .id = -1,
+ .parent = &clk_p,
+ .enable = s3c24xx_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_PWMT,
+ }, {
+ .name = "sdi",
+ .id = -1,
+ .parent = &clk_p,
+ .enable = s3c24xx_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_SDI,
+ }, {
+ .name = "uart",
+ .id = 0,
+ .parent = &clk_p,
+ .enable = s3c24xx_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_UART0,
+ }, {
+ .name = "uart",
+ .id = 1,
+ .parent = &clk_p,
+ .enable = s3c24xx_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_UART1,
+ }, {
+ .name = "uart",
+ .id = 2,
+ .parent = &clk_p,
+ .enable = s3c24xx_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_UART2,
+ }, {
+ .name = "gpio",
+ .id = -1,
+ .parent = &clk_p,
+ .enable = s3c24xx_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_GPIO,
+ }, {
+ .name = "rtc",
+ .id = -1,
+ .parent = &clk_p,
+ .enable = s3c24xx_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_RTC,
+ }, {
+ .name = "adc",
+ .id = -1,
+ .parent = &clk_p,
+ .enable = s3c24xx_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_ADC,
+ }, {
+ .name = "i2c",
+ .id = -1,
+ .parent = &clk_p,
+ .enable = s3c24xx_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_IIC,
+ }, {
+ .name = "iis",
+ .id = -1,
+ .parent = &clk_p,
+ .enable = s3c24xx_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_IIS,
+ }, {
+ .name = "spi",
+ .id = -1,
+ .parent = &clk_p,
+ .enable = s3c24xx_clkcon_enable,
+ .ctrlbit = S3C2410_CLKCON_SPI,
+ }, {
+ .name = "watchdog",
+ .id = -1,
+ .parent = &clk_p,
+ .ctrlbit = 0,
}
};
@@ -370,16 +357,15 @@ static struct clk init_clocks[] = {
int s3c24xx_register_clock(struct clk *clk)
{
clk->owner = THIS_MODULE;
- atomic_set(&clk->used, 0);
if (clk->enable == NULL)
clk->enable = clk_null_enable;
/* add to the list of available clocks */
- down(&clocks_sem);
+ mutex_lock(&clocks_mutex);
list_add(&clk->list, &clocks);
- up(&clocks_sem);
+ mutex_unlock(&clocks_mutex);
return 0;
}
@@ -406,16 +392,15 @@ int __init s3c24xx_setup_clocks(unsigned long xtal,
clk_p.rate = pclk;
clk_f.rate = fclk;
- /* it looks like just setting the register here is not good
- * enough, and causes the odd hang at initial boot time, so
- * do all of them indivdually.
- *
- * I think disabling the LCD clock if the LCD is active is
- * very dangerous, and therefore the bootloader should be
- * careful to not enable the LCD clock if it is not needed.
+ /* We must be careful disabling the clocks we are not intending to
+ * be using at boot time, as subsytems such as the LCD which do
+ * their own DMA requests to the bus can cause the system to lockup
+ * if they where in the middle of requesting bus access.
*
- * and of course, this looks neater
- */
+ * Disabling the LCD clock if the LCD is active is very dangerous,
+ * and therefore the bootloader should be careful to not enable
+ * the LCD clock if it is not needed.
+ */
s3c24xx_clk_enable(S3C2410_CLKCON_NAND, 0);
s3c24xx_clk_enable(S3C2410_CLKCON_USBH, 0);