pinctrl: sunxi: Properly handle level triggered gpio irqs

---
 drivers/pinctrl/sunxi/pinctrl-sunxi.c | 1 +
 1 file changed, 1 insertion(+)

drivers/pinctrl/sunxi/pinctrl-sunxi.c +1 -0

index d989a10..c199337 100644
@@ -630,6 +630,7 @@ static struct irq_chip sunxi_pinctrl_irq_chip = {
 	.irq_mask	= sunxi_pinctrl_irq_mask,
 	.irq_unmask	= sunxi_pinctrl_irq_unmask,
 	.irq_set_type	= sunxi_pinctrl_irq_set_type,
+	.flags		= IRQCHIP_SKIP_SET_WAKE,
 };
 
 static void sunxi_pinctrl_irq_handler(unsigned irq, struct irq_desc *desc)

Signature · 1 line

2.0.0

Linus Walleij

2014-07-04 21:32 UTC #2 lore raw

PATCH v3 1/4 pinctrl: sunxi: Add IRQCHIP_SKIP_SET_WAKE flag for pinctrl irq chip

Quoted 9 lines · Hans de Goede

From: Chen-Yu Tsai <[email protected]>
The sunxi pinctrl irq chip driver does not support wakeup at the moment. Adding IRQCHIP_SKIP_SET_WAKE lets the irqs work with drivers using wakeup.
Signed-off-by Chen-Yu Tsai <[email protected]>
Signed-off-by Hans de Goede <[email protected]>
Acked-by Maxime Ripard <[email protected]>

Patch applied.

Yours,
Linus Walleij

Hans de Goede

author

2014-06-29 14:11 UTC #3 lore raw

PATCH v3 2/4 pinctrl: sunxi: Move setting of mux to irq type from unmask to request_resources

With level triggered interrupt mask / unmask will get called for each interrupt, doing the somewhat expensive mux setting on each unmask thus is not a good idea. Instead add a request_resources callback and do it there.

---
 drivers/pinctrl/sunxi/pinctrl-sunxi.c | 24 ++++++++++++++++--------
 1 file changed, 16 insertions(+), 8 deletions(-)

drivers/pinctrl/sunxi/pinctrl-sunxi.c +16 -8

index c199337..8bdd65b 100644
@@ -531,6 +531,21 @@ static int sunxi_pinctrl_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 	return irq_find_mapping(pctl->domain, desc->irqnum);
 }
 
+static int sunxi_pinctrl_irq_request_resources(struct irq_data *d)
+{
+	struct sunxi_pinctrl *pctl = irq_data_get_irq_chip_data(d);
+	struct sunxi_desc_function *func;
+
+	func = sunxi_pinctrl_desc_find_function_by_pin(pctl,
+					pctl->irq_array[d->hwirq], "irq");
+	if (!func)
+		return -EINVAL;
+
+	/* Change muxing to INT mode */
+	sunxi_pmx_set(pctl->pctl_dev, pctl->irq_array[d->hwirq], func->muxval);
+
+	return 0;
+}
 
 static int sunxi_pinctrl_irq_set_type(struct irq_data *d,
 				      unsigned int type)

@@ -603,19 +618,11 @@ static void sunxi_pinctrl_irq_mask(struct irq_data *d)
 static void sunxi_pinctrl_irq_unmask(struct irq_data *d)
 {
 	struct sunxi_pinctrl *pctl = irq_data_get_irq_chip_data(d);
-	struct sunxi_desc_function *func;
 	u32 reg = sunxi_irq_ctrl_reg(d->hwirq);
 	u8 idx = sunxi_irq_ctrl_offset(d->hwirq);
 	unsigned long flags;
 	u32 val;
 
-	func = sunxi_pinctrl_desc_find_function_by_pin(pctl,
-						       pctl->irq_array[d->hwirq],
-						       "irq");
-
-	/* Change muxing to INT mode */
-	sunxi_pmx_set(pctl->pctl_dev, pctl->irq_array[d->hwirq], func->muxval);
-
 	spin_lock_irqsave(&pctl->lock, flags);
 
 	/* Unmask the IRQ */

@@ -629,6 +636,7 @@ static struct irq_chip sunxi_pinctrl_irq_chip = {
 	.irq_ack	= sunxi_pinctrl_irq_ack,
 	.irq_mask	= sunxi_pinctrl_irq_mask,
 	.irq_unmask	= sunxi_pinctrl_irq_unmask,
+	.irq_request_resources = sunxi_pinctrl_irq_request_resources,
 	.irq_set_type	= sunxi_pinctrl_irq_set_type,
 	.flags		= IRQCHIP_SKIP_SET_WAKE,
 };

Signature · 1 line

2.0.0

Linus Walleij

2014-07-04 21:33 UTC #4 lore raw

PATCH v3 2/4 pinctrl: sunxi: Move setting of mux to irq type from unmask to request_resources

Quoted 6 lines · Hans de Goede

With level triggered interrupt mask / unmask will get called for each interrupt, doing the somewhat expensive mux setting on each unmask thus is not a good idea. Instead add a request_resources callback and do it there.
Signed-off-by Hans de Goede <[email protected]>
Acked-by Maxime Ripard <[email protected]>

Patch applied.

Yours,
Linus Walleij

Hans de Goede

author

2014-06-29 14:11 UTC #5 lore raw

PATCH v3 3/4 pinctrl: sunxi: Properly handle level triggered gpio interrupts

For level triggered gpio interrupts we need to use handle_fasteoi_irq, like we do with the irq-sunxi-nmi driver. This is necessary to give threaded interrupt handlers a chance to actuall clear the source of the interrupt (which may involve sleeping waiting for i2c / spi / mmc transfers), before acknowledging the interrupt.

---
 drivers/pinctrl/sunxi/pinctrl-sunxi.c | 39 ++++++++++++++++++++++++++++-------
 1 file changed, 31 insertions(+), 8 deletions(-)

drivers/pinctrl/sunxi/pinctrl-sunxi.c +31 -8

index 8bdd65b..c1f0530 100644
@@ -31,6 +31,9 @@
 #include "../core.h"
 #include "pinctrl-sunxi.h"
 
+static struct irq_chip sunxi_pinctrl_edge_irq_chip;
+static struct irq_chip sunxi_pinctrl_level_irq_chip;
+
 static struct sunxi_pinctrl_group *
 sunxi_pinctrl_find_group_by_name(struct sunxi_pinctrl *pctl, const char *group)
 {

@@ -547,10 +550,10 @@ static int sunxi_pinctrl_irq_request_resources(struct irq_data *d)
 	return 0;
 }
 
-static int sunxi_pinctrl_irq_set_type(struct irq_data *d,
-				      unsigned int type)
+static int sunxi_pinctrl_irq_set_type(struct irq_data *d, unsigned int type)
 {
 	struct sunxi_pinctrl *pctl = irq_data_get_irq_chip_data(d);
+	struct irq_desc *desc = container_of(d, struct irq_desc, irq_data);
 	u32 reg = sunxi_irq_cfg_reg(d->hwirq);
 	u8 index = sunxi_irq_cfg_offset(d->hwirq);
 	unsigned long flags;

@@ -577,6 +580,14 @@ static int sunxi_pinctrl_irq_set_type(struct irq_data *d,
 		return -EINVAL;
 	}
 
+	if (type & IRQ_TYPE_LEVEL_MASK) {
+		d->chip = &sunxi_pinctrl_level_irq_chip;
+		desc->handle_irq = handle_fasteoi_irq;
+	} else {
+		d->chip = &sunxi_pinctrl_edge_irq_chip;
+		desc->handle_irq = handle_edge_irq;
+	}
+
 	spin_lock_irqsave(&pctl->lock, flags);
 
 	regval = readl(pctl->membase + reg);

@@ -632,7 +643,7 @@ static void sunxi_pinctrl_irq_unmask(struct irq_data *d)
 	spin_unlock_irqrestore(&pctl->lock, flags);
 }
 
-static struct irq_chip sunxi_pinctrl_irq_chip = {
+static struct irq_chip sunxi_pinctrl_edge_irq_chip = {
 	.irq_ack	= sunxi_pinctrl_irq_ack,
 	.irq_mask	= sunxi_pinctrl_irq_mask,
 	.irq_unmask	= sunxi_pinctrl_irq_unmask,

@@ -641,6 +652,16 @@ static struct irq_chip sunxi_pinctrl_irq_chip = {
 	.flags		= IRQCHIP_SKIP_SET_WAKE,
 };
 
+static struct irq_chip sunxi_pinctrl_level_irq_chip = {
+	.irq_eoi	= sunxi_pinctrl_irq_ack,
+	.irq_mask	= sunxi_pinctrl_irq_mask,
+	.irq_unmask	= sunxi_pinctrl_irq_unmask,
+	.irq_request_resources = sunxi_pinctrl_irq_request_resources,
+	.irq_set_type	= sunxi_pinctrl_irq_set_type,
+	.flags		= IRQCHIP_SKIP_SET_WAKE | IRQCHIP_EOI_THREADED |
+			  IRQCHIP_EOI_IF_HANDLED,
+};
+
 static void sunxi_pinctrl_irq_handler(unsigned irq, struct irq_desc *desc)
 {
 	struct irq_chip *chip = irq_get_chip(irq);

@@ -657,9 +678,6 @@ static void sunxi_pinctrl_irq_handler(unsigned irq, struct irq_desc *desc)
 	reg = sunxi_irq_status_reg_from_bank(bank);
 	val = readl(pctl->membase + reg);
 
-	/* Clear all interrupts */
-	writel(val, pctl->membase + reg);
-
 	if (val) {
 		int irqoffset;

@@ -929,12 +947,17 @@ int sunxi_pinctrl_init(struct platform_device *pdev,
 	for (i = 0; i < (pctl->desc->irq_banks * IRQ_PER_BANK); i++) {
 		int irqno = irq_create_mapping(pctl->domain, i);
 
-		irq_set_chip_and_handler(irqno, &sunxi_pinctrl_irq_chip,
-					 handle_simple_irq);
+		irq_set_chip_and_handler(irqno, &sunxi_pinctrl_edge_irq_chip,
+					 handle_edge_irq);
 		irq_set_chip_data(irqno, pctl);
 	};
 
 	for (i = 0; i < pctl->desc->irq_banks; i++) {
+		/* Mask and clear all IRQs before registering a handler */
+		writel(0, pctl->membase + sunxi_irq_ctrl_reg_from_bank(i));
+		writel(0xffffffff,
+			pctl->membase + sunxi_irq_status_reg_from_bank(i));
+
 		irq_set_chained_handler(pctl->irq[i],
 					sunxi_pinctrl_irq_handler);
 		irq_set_handler_data(pctl->irq[i], pctl);

Signature · 1 line

2.0.0

Maxime Ripard

2014-07-01 14:41 UTC #6 lore raw

PATCH v3 3/4 pinctrl: sunxi: Properly handle level triggered gpio interrupts

Quoted 7 lines · Hans de Goede

For level triggered gpio interrupts we need to use handle_fasteoi_irq, like we do with the irq-sunxi-nmi driver. This is necessary to give threaded interrupt handlers a chance to actuall clear the source of the interrupt (which may involve sleeping waiting for i2c / spi / mmc transfers), before acknowledging the interrupt.
Signed-off-by Hans de Goede <[email protected]>

Thanks!
Maxime

Signature · 10 lines

Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
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Linus Walleij

2014-07-04 21:35 UTC #7 lore raw

PATCH v3 3/4 pinctrl: sunxi: Properly handle level triggered gpio interrupts

Quoted 7 lines · Hans de Goede

For level triggered gpio interrupts we need to use handle_fasteoi_irq, like we do with the irq-sunxi-nmi driver. This is necessary to give threaded interrupt handlers a chance to actuall clear the source of the interrupt (which may involve sleeping waiting for i2c / spi / mmc transfers), before acknowledging the interrupt.
Signed-off-by Hans de Goede <[email protected]>

Patch applied with Maxime's ACK.

Yours,
Linus Walleij

Hans de Goede

author

2014-06-29 14:11 UTC #8 lore raw

PATCH v3 4/4 pinctrl: sunxi: Define enable / disable irq callbacks for level triggered irqs

Some drivers use disable_irq / enable_irq and do the work clearing the source in another thread instead of using a threaded interrupt handler.

The irqchip used not having irq_disable and irq_enable callbacks in this case, will lead to unnecessary spurious interrupts:

On a disable_irq in a chip without a handller for this, the irq core will remember the disable, but not actually call into the irqchip. With a level triggered interrupt (where the source has not been cleared) this will lead to an immediate retrigger, at which point the irq-core will mask the irq. So having an irq_disable callback in the irqchip will save us the interrupt firing a 2nd time for nothing.

Drivers using disable / enable_irq like this, will call enable_irq when they finally have cleared the interrupt source, without an enable_irq callback, this will turn into an unmask, at which point the irq will trigger immediately because when it was originally acked the level was still high, so the ack was a nop.

---
 drivers/pinctrl/sunxi/pinctrl-sunxi.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

drivers/pinctrl/sunxi/pinctrl-sunxi.c +10 -0

index c1f0530..c641566 100644
@@ -643,6 +643,12 @@ static void sunxi_pinctrl_irq_unmask(struct irq_data *d)
 	spin_unlock_irqrestore(&pctl->lock, flags);
 }
 
+static void sunxi_pinctrl_irq_ack_unmask(struct irq_data *d)
+{
+	sunxi_pinctrl_irq_ack(d);
+	sunxi_pinctrl_irq_unmask(d);
+}
+
 static struct irq_chip sunxi_pinctrl_edge_irq_chip = {
 	.irq_ack	= sunxi_pinctrl_irq_ack,
 	.irq_mask	= sunxi_pinctrl_irq_mask,

@@ -656,6 +662,10 @@ static struct irq_chip sunxi_pinctrl_level_irq_chip = {
 	.irq_eoi	= sunxi_pinctrl_irq_ack,
 	.irq_mask	= sunxi_pinctrl_irq_mask,
 	.irq_unmask	= sunxi_pinctrl_irq_unmask,
+	/* Define irq_enable / disable to avoid spurious irqs for drivers
+	 * using these to suppress irqs while they clear the irq source */
+	.irq_enable	= sunxi_pinctrl_irq_ack_unmask,
+	.irq_disable	= sunxi_pinctrl_irq_mask,
 	.irq_request_resources = sunxi_pinctrl_irq_request_resources,
 	.irq_set_type	= sunxi_pinctrl_irq_set_type,
 	.flags		= IRQCHIP_SKIP_SET_WAKE | IRQCHIP_EOI_THREADED |

Signature · 1 line

2.0.0

Maxime Ripard

2014-07-01 14:45 UTC #9 lore raw

PATCH v3 4/4 pinctrl: sunxi: Define enable / disable irq callbacks for level triggered irqs

Quoted 13 lines · Hans de Goede

Some drivers use disable_irq / enable_irq and do the work clearing the source in another thread instead of using a threaded interrupt handler.
The irqchip used not having irq_disable and irq_enable callbacks in this case, will lead to unnecessary spurious interrupts:
On a disable_irq in a chip without a handller for this, the irq core will remember the disable, but not actually call into the irqchip. With a level triggered interrupt (where the source has not been cleared) this will lead to an immediate retrigger, at which point the irq-core will mask the irq. So having an irq_disable callback in the irqchip will save us the interrupt firing a 2nd time for nothing.

Quoted 7 lines

Drivers using disable / enable_irq like this, will call enable_irq when they finally have cleared the interrupt source, without an enable_irq callback, this will turn into an unmask, at which point the irq will trigger immediately because when it was originally acked the level was still high, so the ack was a nop.
Signed-off-by Hans de Goede <[email protected]>

Maxime

Signature · 10 lines

Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
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Linus Walleij

2014-07-04 21:39 UTC #10 lore raw

PATCH v3 4/4 pinctrl: sunxi: Define enable / disable irq callbacks for level triggered irqs