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path: root/drivers/clk/at91/clk-system.c
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Diffstat (limited to 'drivers/clk/at91/clk-system.c')
-rw-r--r--drivers/clk/at91/clk-system.c74
1 files changed, 64 insertions, 10 deletions
diff --git a/drivers/clk/at91/clk-system.c b/drivers/clk/at91/clk-system.c
index 48c89fe..8c96307 100644
--- a/drivers/clk/at91/clk-system.c
+++ b/drivers/clk/at91/clk-system.c
@@ -14,6 +14,11 @@
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/of_irq.h>
+#include <linux/interrupt.h>
+#include <linux/wait.h>
+#include <linux/sched.h>
#include "pmc.h"
@@ -25,19 +30,48 @@
struct clk_system {
struct clk_hw hw;
struct at91_pmc *pmc;
+ unsigned int irq;
+ wait_queue_head_t wait;
u8 id;
};
-static int clk_system_enable(struct clk_hw *hw)
+static inline int is_pck(int id)
+{
+ return (id >= 8) && (id <= 15);
+}
+static irqreturn_t clk_system_irq_handler(int irq, void *dev_id)
+{
+ struct clk_system *sys = (struct clk_system *)dev_id;
+
+ wake_up(&sys->wait);
+ disable_irq_nosync(sys->irq);
+
+ return IRQ_HANDLED;
+}
+
+static int clk_system_prepare(struct clk_hw *hw)
{
struct clk_system *sys = to_clk_system(hw);
struct at91_pmc *pmc = sys->pmc;
+ u32 mask = 1 << sys->id;
- pmc_write(pmc, AT91_PMC_SCER, 1 << sys->id);
+ pmc_write(pmc, AT91_PMC_SCER, mask);
+
+ if (!is_pck(sys->id))
+ return 0;
+
+ while (!(pmc_read(pmc, AT91_PMC_SR) & mask)) {
+ if (sys->irq) {
+ enable_irq(sys->irq);
+ wait_event(sys->wait,
+ pmc_read(pmc, AT91_PMC_SR) & mask);
+ } else
+ cpu_relax();
+ }
return 0;
}
-static void clk_system_disable(struct clk_hw *hw)
+static void clk_system_unprepare(struct clk_hw *hw)
{
struct clk_system *sys = to_clk_system(hw);
struct at91_pmc *pmc = sys->pmc;
@@ -45,27 +79,34 @@ static void clk_system_disable(struct clk_hw *hw)
pmc_write(pmc, AT91_PMC_SCDR, 1 << sys->id);
}
-static int clk_system_is_enabled(struct clk_hw *hw)
+static int clk_system_is_prepared(struct clk_hw *hw)
{
struct clk_system *sys = to_clk_system(hw);
struct at91_pmc *pmc = sys->pmc;
- return !!(pmc_read(pmc, AT91_PMC_SCSR) & (1 << sys->id));
+ if (!(pmc_read(pmc, AT91_PMC_SCSR) & (1 << sys->id)))
+ return 0;
+
+ if (!is_pck(sys->id))
+ return 1;
+
+ return !!(pmc_read(pmc, AT91_PMC_SR) & (1 << sys->id));
}
static const struct clk_ops system_ops = {
- .enable = clk_system_enable,
- .disable = clk_system_disable,
- .is_enabled = clk_system_is_enabled,
+ .prepare = clk_system_prepare,
+ .unprepare = clk_system_unprepare,
+ .is_prepared = clk_system_is_prepared,
};
static struct clk * __init
at91_clk_register_system(struct at91_pmc *pmc, const char *name,
- const char *parent_name, u8 id)
+ const char *parent_name, u8 id, int irq)
{
struct clk_system *sys;
struct clk *clk = NULL;
struct clk_init_data init;
+ int ret;
if (!parent_name || id > SYSTEM_MAX_ID)
return ERR_PTR(-EINVAL);
@@ -89,6 +130,15 @@ at91_clk_register_system(struct at91_pmc *pmc, const char *name,
sys->id = id;
sys->hw.init = &init;
sys->pmc = pmc;
+ sys->irq = irq;
+ if (irq) {
+ init_waitqueue_head(&sys->wait);
+ irq_set_status_flags(sys->irq, IRQ_NOAUTOEN);
+ ret = request_irq(sys->irq, clk_system_irq_handler,
+ IRQF_TRIGGER_HIGH, name, sys);
+ if (ret)
+ return ERR_PTR(ret);
+ }
clk = clk_register(NULL, &sys->hw);
if (IS_ERR(clk))
@@ -101,6 +151,7 @@ static void __init
of_at91_clk_sys_setup(struct device_node *np, struct at91_pmc *pmc)
{
int num;
+ int irq = 0;
u32 id;
struct clk *clk;
const char *name;
@@ -118,9 +169,12 @@ of_at91_clk_sys_setup(struct device_node *np, struct at91_pmc *pmc)
if (of_property_read_string(np, "clock-output-names", &name))
name = sysclknp->name;
+ if (is_pck(id))
+ irq = irq_of_parse_and_map(sysclknp, 0);
+
parent_name = of_clk_get_parent_name(sysclknp, 0);
- clk = at91_clk_register_system(pmc, name, parent_name, id);
+ clk = at91_clk_register_system(pmc, name, parent_name, id, irq);
if (IS_ERR(clk))
continue;
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