clocksource: nomadik-mtu: support of probe

Support device tree probe of the nomadik-mtu clocksource.

Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>

1 files changed, 58 insertions, 12 deletions

diff --git a/drivers/clocksource/nomadik-mtu.c b/drivers/clocksource/nomadik-mtu.c
index e405531e1cc5..7982cb0f25f2 100644
--- a/drivers/clocksource/nomadik-mtu.c
+++ b/drivers/clocksource/nomadik-mtu.c
@@ -13,6 +13,9 @@
 #include <linux/io.h>
 #include <linux/clockchips.h>
 #include <linux/clocksource.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
 #include <linux/clk.h>
 #include <linux/jiffies.h>
 #include <linux/delay.h>
@@ -188,22 +191,15 @@ static struct irqaction nmdk_timer_irq = {
         .dev_id         = &nmdk_clkevt,
 };
 
-void __init nmdk_timer_init(void __iomem *base, int irq)
+static void __init __nmdk_timer_init(void __iomem *base, int irq,
+                                     struct clk *pclk, struct clk *clk)
 {
         unsigned long rate;
-        struct clk *clk0, *pclk0;
 
         mtu_base = base;
 
-        pclk0 = clk_get_sys("mtu0", "apb_pclk");
-        BUG_ON(IS_ERR(pclk0));
-        BUG_ON(clk_prepare(pclk0) < 0);
-        BUG_ON(clk_enable(pclk0) < 0);
-
-        clk0 = clk_get_sys("mtu0", NULL);
-        BUG_ON(IS_ERR(clk0));
-        BUG_ON(clk_prepare(clk0) < 0);
-        BUG_ON(clk_enable(clk0) < 0);
+        BUG_ON(clk_prepare_enable(pclk));
+        BUG_ON(clk_prepare_enable(clk));
 
         /*
          * Tick rate is 2.4MHz for Nomadik and 2.4Mhz, 100MHz or 133 MHz
@@ -213,7 +209,7 @@ void __init nmdk_timer_init(void __iomem *base, int irq)
          * to wake-up at a max 127s a head in time. Dividing a 2.4 MHz timer
          * with 16 gives too low timer resolution.
          */
-        rate = clk_get_rate(clk0);
+        rate = clk_get_rate(clk);
         if (rate > 32000000) {
                 rate /= 16;
                 clk_prescale = MTU_CRn_PRESCALE_16;
@@ -247,3 +243,53 @@ void __init nmdk_timer_init(void __iomem *base, int irq)
         mtu_delay_timer.freq = rate;
         register_current_timer_delay(&mtu_delay_timer);
 }
+
+void __init nmdk_timer_init(void __iomem *base, int irq)
+{
+        struct clk *clk0, *pclk0;
+
+        pclk0 = clk_get_sys("mtu0", "apb_pclk");
+        BUG_ON(IS_ERR(pclk0));
+        clk0 = clk_get_sys("mtu0", NULL);
+        BUG_ON(IS_ERR(clk0));
+
+        __nmdk_timer_init(base, irq, pclk0, clk0);
+}
+
+static struct of_device_id nmdk_timer_match[] __initconst = {
+        { .compatible = "st,nomadik-mtu" },
+        {}
+};
+
+static void __init nmdk_timer_of_init(void)
+{
+        struct device_node *node;
+        struct clk *pclk;
+        struct clk *clk;
+        void __iomem *base;
+        int irq;
+
+        node = of_find_matching_node(NULL, nmdk_timer_match);
+        if (!node)
+                panic("No timer node");
+
+        base = of_iomap(node, 0);
+        if (!base)
+                panic("Can't remap registers");
+
+        pclk = of_clk_get_by_name(node, "apb_pclk");
+        if (IS_ERR(pclk))
+                panic("could not get apb_pclk");
+
+        clk = of_clk_get_by_name(node, "timclk");
+        if (IS_ERR(clk))
+                panic("could not get timclk");
+
+        irq = irq_of_parse_and_map(node, 0);
+        if (irq <= 0)
+                panic("Can't parse IRQ");
+
+        __nmdk_timer_init(base, irq, pclk, clk);
+}
+CLOCKSOURCE_OF_DECLARE(nomadik_mtu, "st,nomadik-mtu",
+                       nmdk_timer_of_init);