clocksource: samsung_pwm_timer: Add support for non-DT platforms

This patch extends the driver to support platforms that still use legacy
ATAGS-based boot, without device tree, by providing an exported function
that can be used from platform code to initialize the clocksource.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Olof Johansson <olof@lixom.net>

drivers/clocksource/Kconfig

@@ -70,7 +70,6 @@ config CLKSRC_METAG_GENERIC
 
 config CLKSRC_SAMSUNG_PWM
 	bool
-	depends on OF
 	select CLKSRC_MMIO
 	help
 	  This is a new clocksource driver for the PWM timer found in

drivers/clocksource/samsung_pwm_timer.c

@@ -356,7 +356,7 @@ static void __init samsung_timer_resources(void)
 /*
  * PWM master driver
  */
-static void __init samsung_pwm_clocksource_init(void)
+static void __init _samsung_pwm_clocksource_init(void)
 {
 	u8 mask;
 	int channel;
@@ -378,6 +378,17 @@ static void __init samsung_pwm_clocksource_init(void)
 	samsung_clocksource_init();
 }
 
+void __init samsung_pwm_clocksource_init(void __iomem *base,
+			unsigned int *irqs, struct samsung_pwm_variant *variant)
+{
+	pwm.base = base;
+	memcpy(&pwm.variant, variant, sizeof(pwm.variant));
+	memcpy(pwm.irq, irqs, SAMSUNG_PWM_NUM * sizeof(*irqs));
+
+	_samsung_pwm_clocksource_init();
+}
+
+#ifdef CONFIG_CLKSRC_OF
 static void __init samsung_pwm_alloc(struct device_node *np,
 				     const struct samsung_pwm_variant *variant)
 {
@@ -414,7 +425,7 @@ static void __init samsung_pwm_alloc(struct device_node *np,
 		return;
 	}
 
-	samsung_pwm_clocksource_init();
+	_samsung_pwm_clocksource_init();
 }
 
 static const struct samsung_pwm_variant s3c24xx_variant = {
@@ -468,3 +479,4 @@ static void __init s5p_pwm_clocksource_init(struct device_node *np)
 	samsung_pwm_alloc(np, &s5p_variant);
 }
 CLOCKSOURCE_OF_DECLARE(s5pc100_pwm, "samsung,s5pc100-pwm", s5p_pwm_clocksource_init);
+#endif

include/clocksource/samsung_pwm.h

@@ -30,4 +30,7 @@ struct samsung_pwm_variant {
 	bool has_tint_cstat;
 };
 
+void samsung_pwm_clocksource_init(void __iomem *base,
+		unsigned int *irqs, struct samsung_pwm_variant *variant);
+
 #endif /* __CLOCKSOURCE_SAMSUNG_PWM_H */