diff --git a/arch/arm/mach-s5p6440/cpu.c b/arch/arm/mach-s5p6440/cpu.c
index 526f33adb31d65e56d0a5064f3ac7b16496eef33..ec592e8660547a45956bcddc4bb6426523973b30 100644
--- a/arch/arm/mach-s5p6440/cpu.c
+++ b/arch/arm/mach-s5p6440/cpu.c
@@ -19,6 +19,7 @@
 #include <linux/sysdev.h>
 #include <linux/serial_core.h>
 #include <linux/platform_device.h>
+#include <linux/sched.h>
 
 #include <asm/mach/arch.h>
 #include <asm/mach/map.h>
diff --git a/arch/arm/mach-s5p6442/cpu.c b/arch/arm/mach-s5p6442/cpu.c
index a48fb553fd01cf5d42e1ab590146d7cad1e7680f..70ac681af72bc7a1a9ce5434c164e5b86e1fdf55 100644
--- a/arch/arm/mach-s5p6442/cpu.c
+++ b/arch/arm/mach-s5p6442/cpu.c
@@ -19,6 +19,7 @@
 #include <linux/sysdev.h>
 #include <linux/serial_core.h>
 #include <linux/platform_device.h>
+#include <linux/sched.h>
 
 #include <asm/mach/arch.h>
 #include <asm/mach/map.h>
diff --git a/arch/arm/mach-s5pc100/cpu.c b/arch/arm/mach-s5pc100/cpu.c
index 251c92ac5b227e05a28251ed7b890ff1f84eccfb..cd1afbce83e2cfa6d006d6084e384e1705408be8 100644
--- a/arch/arm/mach-s5pc100/cpu.c
+++ b/arch/arm/mach-s5pc100/cpu.c
@@ -21,6 +21,7 @@
 #include <linux/sysdev.h>
 #include <linux/serial_core.h>
 #include <linux/platform_device.h>
+#include <linux/sched.h>
 
 #include <asm/mach/arch.h>
 #include <asm/mach/map.h>
diff --git a/arch/arm/mach-s5pv210/clock.c b/arch/arm/mach-s5pv210/clock.c
index cfecd70657cb62e51d01ad820ce2f7856957f9fc..d562670e1b0b44005ade9644f69338de44b459bb 100644
--- a/arch/arm/mach-s5pv210/clock.c
+++ b/arch/arm/mach-s5pv210/clock.c
@@ -173,11 +173,6 @@ static int s5pv210_clk_ip3_ctrl(struct clk *clk, int enable)
 	return s5p_gatectrl(S5P_CLKGATE_IP3, clk, enable);
 }
 
-static int s5pv210_clk_ip4_ctrl(struct clk *clk, int enable)
-{
-	return s5p_gatectrl(S5P_CLKGATE_IP4, clk, enable);
-}
-
 static int s5pv210_clk_mask0_ctrl(struct clk *clk, int enable)
 {
 	return s5p_gatectrl(S5P_CLK_SRC_MASK0, clk, enable);
diff --git a/arch/arm/mach-s5pv210/cpu.c b/arch/arm/mach-s5pv210/cpu.c
index 77f456c91ad36ba97001630613f9c75d1d335819..245b82b53df4612d63d45984659e2221605d124f 100644
--- a/arch/arm/mach-s5pv210/cpu.c
+++ b/arch/arm/mach-s5pv210/cpu.c
@@ -19,6 +19,7 @@
 #include <linux/io.h>
 #include <linux/sysdev.h>
 #include <linux/platform_device.h>
+#include <linux/sched.h>
 
 #include <asm/mach/arch.h>
 #include <asm/mach/map.h>
diff --git a/arch/arm/plat-samsung/adc.c b/arch/arm/plat-samsung/adc.c
index 04d9521ddc9f0e652d62453a99bbb19fa877c7fa..e8f2be2d67f2cac33961487b47a7880b68f33832 100644
--- a/arch/arm/plat-samsung/adc.c
+++ b/arch/arm/plat-samsung/adc.c
@@ -435,7 +435,6 @@ static int s3c_adc_suspend(struct platform_device *pdev, pm_message_t state)
 static int s3c_adc_resume(struct platform_device *pdev)
 {
 	struct adc_device *adc = platform_get_drvdata(pdev);
-	unsigned long flags;
 
 	clk_enable(adc->clk);
 	enable_irq(adc->irq);
diff --git a/arch/arm/plat-samsung/clock.c b/arch/arm/plat-samsung/clock.c
index 90a20512d68d5a40d9fa789b15c24620a0c8f9b3..e8d20b0bc50e11ee43d78f230b811409def1cb87 100644
--- a/arch/arm/plat-samsung/clock.c
+++ b/arch/arm/plat-samsung/clock.c
@@ -48,6 +48,9 @@
 #include <plat/clock.h>
 #include <plat/cpu.h>
 
+#include <linux/serial_core.h>
+#include <plat/regs-serial.h> /* for s3c24xx_uart_devs */
+
 /* clock information */
 
 static LIST_HEAD(clocks);
@@ -65,6 +68,28 @@ static int clk_null_enable(struct clk *clk, int enable)
 	return 0;
 }
 
+static int dev_is_s3c_uart(struct device *dev)
+{
+	struct platform_device **pdev = s3c24xx_uart_devs;
+	int i;
+	for (i = 0; i < ARRAY_SIZE(s3c24xx_uart_devs); i++, pdev++)
+		if (*pdev && dev == &(*pdev)->dev)
+			return 1;
+	return 0;
+}
+
+/*
+ * Serial drivers call get_clock() very early, before platform bus
+ * has been set up, this requires a special check to let them get
+ * a proper clock
+ */
+
+static int dev_is_platform_device(struct device *dev)
+{
+	return dev->bus == &platform_bus_type ||
+	       (dev->bus == NULL && dev_is_s3c_uart(dev));
+}
+
 /* Clock API calls */
 
 struct clk *clk_get(struct device *dev, const char *id)
@@ -73,7 +98,7 @@ struct clk *clk_get(struct device *dev, const char *id)
 	struct clk *clk = ERR_PTR(-ENOENT);
 	int idno;
 
-	if (dev == NULL || dev->bus != &platform_bus_type)
+	if (dev == NULL || !dev_is_platform_device(dev))
 		idno = -1;
 	else
 		idno = to_platform_device(dev)->id;