[PATCH 2/6] mfd: Provide the PRCMU with its own IRQ domain

[Lee Jones]

The PRCMU has its own USB, Thermal, GPIO, Modem, HSI and RTC drivers,
amongst other things. This patch allows those subordinate devices to
use it as an interrupt controller as and when they are DT enabled.

Signed-off-by: Lee Jones <lee.jones at linaro.org>
---
 drivers/mfd/db8500-prcmu.c       |   54 +++++++++++++++++++++++++++++---------
 include/linux/mfd/db8500-prcmu.h |    2 ++
 2 files changed, 43 insertions(+), 13 deletions(-)

diff --git a/drivers/mfd/db8500-prcmu.c b/drivers/mfd/db8500-prcmu.c
index 7040a00..937ce3a 100644
--- a/drivers/mfd/db8500-prcmu.c
+++ b/drivers/mfd/db8500-prcmu.c
@@ -270,6 +270,8 @@ static struct {
 	struct prcmu_fw_version version;
 } fw_info;
 
+struct irq_domain *db8500_irq_domain;
+
 /*
  * This vector maps irq numbers to the bits in the bit field used in
  * communication with the PRCMU firmware.
@@ -2583,7 +2585,7 @@ static void prcmu_irq_mask(struct irq_data *d)
 
 	spin_lock_irqsave(&mb0_transfer.dbb_irqs_lock, flags);
 
-	mb0_transfer.req.dbb_irqs &= ~prcmu_irq_bit[d->irq - IRQ_PRCMU_BASE];
+	mb0_transfer.req.dbb_irqs &= ~prcmu_irq_bit[d->hwirq];
 
 	spin_unlock_irqrestore(&mb0_transfer.dbb_irqs_lock, flags);
 
@@ -2597,7 +2599,7 @@ static void prcmu_irq_unmask(struct irq_data *d)
 
 	spin_lock_irqsave(&mb0_transfer.dbb_irqs_lock, flags);
 
-	mb0_transfer.req.dbb_irqs |= prcmu_irq_bit[d->irq - IRQ_PRCMU_BASE];
+	mb0_transfer.req.dbb_irqs |= prcmu_irq_bit[d->hwirq];
 
 	spin_unlock_irqrestore(&mb0_transfer.dbb_irqs_lock, flags);
 
@@ -2637,9 +2639,43 @@ static char *fw_project_name(u8 project)
 	}
 }
 
+int db8500_irq_get_virq(int irq)
+{
+	return irq_create_mapping(db8500_irq_domain, irq);
+}
+EXPORT_SYMBOL_GPL(db8500_irq_get_virq);
+
+static int db8500_irq_map(struct irq_domain *d, unsigned int virq,
+				irq_hw_number_t hwirq)
+{
+	irq_set_chip_and_handler(virq, &prcmu_irq_chip,
+				handle_simple_irq);
+	set_irq_flags(virq, IRQF_VALID);
+
+	return 0;
+}
+
+static struct irq_domain_ops db8500_irq_ops = {
+        .map    = db8500_irq_map,
+        .xlate  = irq_domain_xlate_twocell,
+};
+
+static int db8500_irq_init(struct device_node *np)
+{
+	db8500_irq_domain = irq_domain_add_legacy(
+		np, NUM_PRCMU_WAKEUPS, IRQ_PRCMU_BASE,
+		0, &db8500_irq_ops, NULL);
+
+	if (!db8500_irq_domain) {
+		pr_err("Failed to create irqdomain\n");
+		return -ENOSYS;
+	}
+
+	return 0;
+}
+
 void __init db8500_prcmu_early_init(void)
 {
-	unsigned int i;
 	if (cpu_is_u8500v2()) {
 		void *tcpm_base = ioremap_nocache(U8500_PRCMU_TCPM_BASE, SZ_4K);
 
@@ -2683,16 +2719,6 @@ void __init db8500_prcmu_early_init(void)
 	init_completion(&mb5_transfer.work);
 
 	INIT_WORK(&mb0_transfer.mask_work, prcmu_mask_work);
-
-	/* Initalize irqs. */
-	for (i = 0; i < NUM_PRCMU_WAKEUPS; i++) {
-		unsigned int irq;
-
-		irq = IRQ_PRCMU_BASE + i;
-		irq_set_chip_and_handler(irq, &prcmu_irq_chip,
-					 handle_simple_irq);
-		set_irq_flags(irq, IRQF_VALID);
-	}
 }
 
 static void __init init_prcm_registers(void)
@@ -2999,6 +3025,8 @@ static int __devinit db8500_prcmu_probe(struct platform_device *pdev)
 		goto no_irq_return;
 	}
 
+	db8500_irq_init(np);
+
 	for (i = 0; i < ARRAY_SIZE(db8500_prcmu_devs); i++) {
 		if (!strcmp(db8500_prcmu_devs[i].name, "ab8500-core")) {
 			db8500_prcmu_devs[i].platform_data = ab8500_platdata;
diff --git a/include/linux/mfd/db8500-prcmu.h b/include/linux/mfd/db8500-prcmu.h
index b82f6ee..38494d9 100644
--- a/include/linux/mfd/db8500-prcmu.h
+++ b/include/linux/mfd/db8500-prcmu.h
@@ -571,6 +571,8 @@ u32 db8500_prcmu_read(unsigned int reg);
 void db8500_prcmu_write(unsigned int reg, u32 value);
 void db8500_prcmu_write_masked(unsigned int reg, u32 mask, u32 value);
 
+int db8500_irq_get_virq(int irq);
+
 #else /* !CONFIG_MFD_DB8500_PRCMU */
 
 static inline void db8500_prcmu_early_init(void) {}
-- 
1.7.9.5