[PATCH v2 4/6] clk: at91: implement suspend/resume for the PMC irqchip

Boris Brezillon
2015-03-02T09:20:15Z

The irq line used by the PMC block is shared with several peripherals
including the init timer which is registering its handler with
IRQF_NO_SUSPEND.
Implement the appropriate suspend/resume callback for the PMC irqchip,
and inform irq core that PMC irq handler can be safely called while
the system is suspended by setting IRQF_COND_SUSPEND.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
---
drivers/clk/at91/pmc.c | 20 +++++++++++++++++++-
drivers/clk/at91/pmc.h | 1 +
2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/at91/pmc.c b/drivers/clk/at91/pmc.c
index f07c815..3f27d21 100644
--- a/drivers/clk/at91/pmc.c
+++ b/drivers/clk/at91/pmc.c
@@ -89,12 +89,29 @@ static int pmc_irq_set_type(struct irq_data *d, unsigned type)
return 0;
}

+static void pmc_irq_suspend(struct irq_data *d)
+{
+ struct at91_pmc *pmc = irq_data_get_irq_chip_data(d);
+
+ pmc->imr = pmc_read(pmc, AT91_PMC_IMR);
+ pmc_write(pmc, AT91_PMC_IDR, pmc->imr);
+}
+
+static void pmc_irq_resume(struct irq_data *d)
+{
+ struct at91_pmc *pmc = irq_data_get_irq_chip_data(d);
+
+ pmc_write(pmc, AT91_PMC_IER, pmc->imr);
+}
+
static struct irq_chip pmc_irq = {
.name = "PMC",
.irq_disable = pmc_irq_mask,
.irq_mask = pmc_irq_mask,
.irq_unmask = pmc_irq_unmask,
.irq_set_type = pmc_irq_set_type,
+ .irq_suspend = pmc_irq_suspend,
+ .irq_resume = pmc_irq_resume,
};

static struct lock_class_key pmc_lock_class;
@@ -224,7 +241,8 @@ static struct at91_pmc *__init at91_pmc_init(struct device_node *np,
goto out_free_pmc;

pmc_write(pmc, AT91_PMC_IDR, 0xffffffff);
- if (request_irq(pmc->virq, pmc_irq_handler, IRQF_SHARED, "pmc", pmc))
+ if (request_irq(pmc->virq, pmc_irq_handler,
+ IRQF_SHARED | IRQF_COND_SUSPEND, "pmc", pmc))
goto out_remove_irqdomain;

return pmc;
diff --git a/drivers/clk/at91/pmc.h b/drivers/clk/at91/pmc.h
index 52d2041..69abb08 100644
--- a/drivers/clk/at91/pmc.h
+++ b/drivers/clk/at91/pmc.h
@@ -33,6 +33,7 @@ struct at91_pmc {
spinlock_t lock;
const struct at91_pmc_caps *caps;
struct irq_domain *irqdomain;
+ u32 imr;
};

static inline void pmc_lock(struct at91_pmc *pmc)
--
1.9.1