[PATCH v6 0/4] Add STM32 EXTI interrupt controller support

[PATCH v6 0/4] Add STM32 EXTI interrupt controller support

[Alexandre TORGUE]

Hi,

This v6 fix useless mask in .free callback of stm32 exti driver (thanks
Thomas).
I resend only patches concerning STM32 EXTI driver (as pinctrl part has
already been applied by Linus W.)


The series adds support to EXTI interrupt controller and GPIO IRQ support in
STM32 pinctrl driver.

The STM32 external interrupt controller consists of edge detectors that
generate interrupts requests or wake-up events.

Each line can be independently configured as interrupt or wake-up source,
and triggers either on rising, fallin or both edges. Each line can also
be masked independently.

Regards 

Alex

Changes since v5:
-----------------
 - Fix .free callback according to Thomas

Changes since v4:
-----------------
 - Fix bad copy/paste in stm32 exti driver
 - Remove GPIOLIB_IRQCHIP config in stm32 pinctrl driver 

Changes since v3:
-----------------
 - Review domain dealloc/free irq in stm32 pinctrl driver
 - Review domain dealloc/free irq in stm32 exti driver
 - Fix remarks on coding style

Changes since v2:
-----------------
 - Define irq_chip for GPIO banks
 - Use hierarchical domain for GPIO banks
 - Improve search loop inside stm32_exti handler 
 - Rebased on top of v4.8-rc1

Changes since v1:
-----------------
 - Rebased on top of v4.6-rc1
 - Change variable name from virq to irq (Linus W.)


Alexandre TORGUE (4):
  Documentation: dt-bindings: Document STM32 EXTI controller bindings
  drivers: irqchip: Add STM32 external interrupts support
  ARM: STM32: Select external interrupts controller
  ARM: dts: Add EXTI controller node to stm32f429

 .../interrupt-controller/st,stm32-exti.txt         |  20 ++
 arch/arm/Kconfig                                   |   1 +
 arch/arm/boot/dts/stm32f429.dtsi                   |   8 +
 drivers/irqchip/Kconfig                            |   4 +
 drivers/irqchip/Makefile                           |   1 +
 drivers/irqchip/irq-stm32-exti.c                   | 201 +++++++++++++++++++++
 6 files changed, 235 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/interrupt-controller/st,stm32-exti.txt
 create mode 100644 drivers/irqchip/irq-stm32-exti.c

-- 
1.9.1

[PATCH v6 1/4] Documentation: dt-bindings: Document STM32 EXTI controller bindings

[Alexandre TORGUE]

Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>

diff --git a/Documentation/devicetree/bindings/interrupt-controller/st,stm32-exti.txt b/Documentation/devicetree/bindings/interrupt-controller/st,stm32-exti.txt
new file mode 100644
index 0000000..6e7703d
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/st,stm32-exti.txt
@@ -0,0 +1,20 @@
+STM32 External Interrupt Controller
+
+Required properties:
+
+- compatible: Should be "st,stm32-exti"
+- reg: Specifies base physical address and size of the registers
+- interrupt-controller: Indentifies the node as an interrupt controller
+- #interrupt-cells: Specifies the number of cells to encode an interrupt
+  specifier, shall be 2
+- interrupts: interrupts references to primary interrupt controller
+
+Example:
+
+exti: interrupt-controller at 40013c00 {
+	compatible = "st,stm32-exti";
+	interrupt-controller;
+	#interrupt-cells = <2>;
+	reg = <0x40013C00 0x400>;
+	interrupts = <1>, <2>, <3>, <6>, <7>, <8>, <9>, <10>, <23>, <40>, <41>, <42>, <62>, <76>;
+};
-- 
1.9.1

[PATCH v6 2/4] drivers: irqchip: Add STM32 external interrupts support

[Alexandre TORGUE]

The STM32 external interrupt controller consists of edge detectors that
generate interrupts requests or wake-up events.

Each line can be independently configured as interrupt or wake-up source,
and triggers either on rising, falling or both edges. Each line can also
be masked independently.

Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 7f87289..bc62d1f 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -264,3 +264,7 @@ config EZNPS_GIC
 	select IRQ_DOMAIN
 	help
 	  Support the EZchip NPS400 global interrupt controller
+
+config STM32_EXTI
+	bool
+	select IRQ_DOMAIN
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 4c203b6..96383b2 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -71,3 +71,4 @@ obj-$(CONFIG_MVEBU_ODMI)		+= irq-mvebu-odmi.o
 obj-$(CONFIG_LS_SCFG_MSI)		+= irq-ls-scfg-msi.o
 obj-$(CONFIG_EZNPS_GIC)			+= irq-eznps.o
 obj-$(CONFIG_ARCH_ASPEED)		+= irq-aspeed-vic.o
+obj-$(CONFIG_STM32_EXTI) 		+= irq-stm32-exti.o
diff --git a/drivers/irqchip/irq-stm32-exti.c b/drivers/irqchip/irq-stm32-exti.c
new file mode 100644
index 0000000..491568c
--- /dev/null
+++ b/drivers/irqchip/irq-stm32-exti.c
@@ -0,0 +1,201 @@
+/*
+ * Copyright (C) Maxime Coquelin 2015
+ * Author:  Maxime Coquelin <mcoquelin.stm32@gmail.com>
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+
+#include <linux/bitops.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define EXTI_IMR	0x0
+#define EXTI_EMR	0x4
+#define EXTI_RTSR	0x8
+#define EXTI_FTSR	0xc
+#define EXTI_SWIER	0x10
+#define EXTI_PR		0x14
+
+static void stm32_irq_handler(struct irq_desc *desc)
+{
+	struct irq_domain *domain = irq_desc_get_handler_data(desc);
+	struct irq_chip_generic *gc = domain->gc->gc[0];
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	unsigned long pending;
+	int n;
+
+	chained_irq_enter(chip, desc);
+
+	while ((pending = irq_reg_readl(gc, EXTI_PR))) {
+		for_each_set_bit(n, &pending, BITS_PER_LONG) {
+			generic_handle_irq(irq_find_mapping(domain, n));
+			irq_reg_writel(gc, BIT(n), EXTI_PR);
+		}
+	}
+
+	chained_irq_exit(chip, desc);
+}
+
+static int stm32_irq_set_type(struct irq_data *data, unsigned int type)
+{
+	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
+	int pin = data->hwirq;
+	u32 rtsr, ftsr;
+
+	irq_gc_lock(gc);
+
+	rtsr = irq_reg_readl(gc, EXTI_RTSR);
+	ftsr = irq_reg_readl(gc, EXTI_FTSR);
+
+	switch (type) {
+	case IRQ_TYPE_EDGE_RISING:
+		rtsr |= BIT(pin);
+		ftsr &= ~BIT(pin);
+		break;
+	case IRQ_TYPE_EDGE_FALLING:
+		rtsr &= ~BIT(pin);
+		ftsr |= BIT(pin);
+		break;
+	case IRQ_TYPE_EDGE_BOTH:
+		rtsr |= BIT(pin);
+		ftsr |= BIT(pin);
+		break;
+	default:
+		irq_gc_unlock(gc);
+		return -EINVAL;
+	}
+
+	irq_reg_writel(gc, rtsr, EXTI_RTSR);
+	irq_reg_writel(gc, ftsr, EXTI_FTSR);
+
+	irq_gc_unlock(gc);
+
+	return 0;
+}
+
+static int stm32_irq_set_wake(struct irq_data *data, unsigned int on)
+{
+	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
+	int pin = data->hwirq;
+	u32 emr;
+
+	irq_gc_lock(gc);
+
+	emr = irq_reg_readl(gc, EXTI_EMR);
+	if (on)
+		emr |= BIT(pin);
+	else
+		emr &= ~BIT(pin);
+	irq_reg_writel(gc, emr, EXTI_EMR);
+
+	irq_gc_unlock(gc);
+
+	return 0;
+}
+
+static int stm32_exti_alloc(struct irq_domain *d, unsigned int virq,
+			    unsigned int nr_irqs, void *data)
+{
+	struct irq_chip_generic *gc = d->gc->gc[0];
+	struct irq_fwspec *fwspec = data;
+	irq_hw_number_t hwirq;
+
+	hwirq = fwspec->param[0];
+
+	irq_map_generic_chip(d, virq, hwirq);
+	irq_domain_set_info(d, virq, hwirq, &gc->chip_types->chip, gc,
+			    handle_simple_irq, NULL, NULL);
+
+	return 0;
+}
+
+static void stm32_exti_free(struct irq_domain *d, unsigned int virq,
+			    unsigned int nr_irqs)
+{
+	struct irq_data *data = irq_domain_get_irq_data(d, virq);
+
+	irq_domain_reset_irq_data(data);
+}
+
+struct irq_domain_ops irq_exti_domain_ops = {
+	.map	= irq_map_generic_chip,
+	.xlate	= irq_domain_xlate_onetwocell,
+	.alloc  = stm32_exti_alloc,
+	.free	= stm32_exti_free,
+};
+
+static int __init stm32_exti_init(struct device_node *node,
+				  struct device_node *parent)
+{
+	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
+	int nr_irqs, nr_exti, ret, i;
+	struct irq_chip_generic *gc;
+	struct irq_domain *domain;
+	void *base;
+
+	base = of_iomap(node, 0);
+	if (!base) {
+		pr_err("%s: Unable to map registers\n", node->full_name);
+		return -ENOMEM;
+	}
+
+	/* Determine number of irqs supported */
+	writel_relaxed(~0UL, base + EXTI_RTSR);
+	nr_exti = fls(readl_relaxed(base + EXTI_RTSR));
+	writel_relaxed(0, base + EXTI_RTSR);
+
+	pr_info("%s: %d External IRQs detected\n", node->full_name, nr_exti);
+
+	domain = irq_domain_add_linear(node, nr_exti,
+				       &irq_exti_domain_ops, NULL);
+	if (!domain) {
+		pr_err("%s: Could not register interrupt domain.\n",
+				node->name);
+		ret = -ENOMEM;
+		goto out_unmap;
+	}
+
+	ret = irq_alloc_domain_generic_chips(domain, nr_exti, 1, "exti",
+					     handle_edge_irq, clr, 0, 0);
+	if (ret) {
+		pr_err("%s: Could not allocate generic interrupt chip.\n",
+			node->full_name);
+		goto out_free_domain;
+	}
+
+	gc = domain->gc->gc[0];
+	gc->reg_base                         = base;
+	gc->chip_types->type               = IRQ_TYPE_EDGE_BOTH;
+	gc->chip_types->chip.name          = gc->chip_types[0].chip.name;
+	gc->chip_types->chip.irq_ack       = irq_gc_ack_set_bit;
+	gc->chip_types->chip.irq_mask      = irq_gc_mask_clr_bit;
+	gc->chip_types->chip.irq_unmask    = irq_gc_mask_set_bit;
+	gc->chip_types->chip.irq_set_type  = stm32_irq_set_type;
+	gc->chip_types->chip.irq_set_wake  = stm32_irq_set_wake;
+	gc->chip_types->regs.ack           = EXTI_PR;
+	gc->chip_types->regs.mask          = EXTI_IMR;
+	gc->chip_types->handler            = handle_edge_irq;
+
+	nr_irqs = of_irq_count(node);
+	for (i = 0; i < nr_irqs; i++) {
+		unsigned int irq = irq_of_parse_and_map(node, i);
+
+		irq_set_handler_data(irq, domain);
+		irq_set_chained_handler(irq, stm32_irq_handler);
+	}
+
+	return 0;
+
+out_free_domain:
+	irq_domain_remove(domain);
+out_unmap:
+	iounmap(base);
+	return ret;
+}
+
+IRQCHIP_DECLARE(stm32_exti, "st,stm32-exti", stm32_exti_init);
-- 
1.9.1

[PATCH v6 2/4] drivers: irqchip: Add STM32 external interrupts support

[Thomas Gleixner]

Alexandre,

On Tue, 20 Sep 2016, Alexandre TORGUE wrote:

> The STM32 external interrupt controller consists of edge detectors that
> generate interrupts requests or wake-up events.
> 
> Each line can be independently configured as interrupt or wake-up source,
> and triggers either on rising, falling or both edges. Each line can also
> be masked independently.
> 
> Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
> Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>

That all looks very reasonable now. The only remaining question is your SOB
chain. Who is the author of these patches? You or Maxime? If it's Maxime,
then the changelog misses a From: tag. If it's you then Maximes SOB is
bogus.

Thanks,

	tglx

[PATCH v6 2/4] drivers: irqchip: Add STM32 external interrupts support

[Alexandre Torgue]

Hi Thomas,

On 09/20/2016 10:16 PM, Thomas Gleixner wrote:
> Alexandre,
>
> On Tue, 20 Sep 2016, Alexandre TORGUE wrote:
>
>> The STM32 external interrupt controller consists of edge detectors that
>> generate interrupts requests or wake-up events.
>>
>> Each line can be independently configured as interrupt or wake-up source,
>> and triggers either on rising, falling or both edges. Each line can also
>> be masked independently.
>>
>> Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
>> Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
>
> That all looks very reasonable now. The only remaining question is your SOB
> chain. Who is the author of these patches? You or Maxime? If it's Maxime,
> then the changelog misses a From: tag. If it's you then Maximes SOB is
> bogus.

Actually Maxime wrote the main part of this driver and sent version 1 
and 2 of the series. After Linus W. reviews, rework was required to use 
hierarchical domain. According to Maxime, I coded the rework (adaptation 
to hierarchical domain) and sent other version of the series.

Regards

Alex

>
> Thanks,
>
> 	tglx
>
>

[PATCH v6 2/4] drivers: irqchip: Add STM32 external interrupts support

[Thomas Gleixner]

On Wed, 21 Sep 2016, Alexandre Torgue wrote:

> Hi Thomas,
> 
> On 09/20/2016 10:16 PM, Thomas Gleixner wrote:
> > Alexandre,
> > 
> > On Tue, 20 Sep 2016, Alexandre TORGUE wrote:
> > 
> > > The STM32 external interrupt controller consists of edge detectors that
> > > generate interrupts requests or wake-up events.
> > > 
> > > Each line can be independently configured as interrupt or wake-up source,
> > > and triggers either on rising, falling or both edges. Each line can also
> > > be masked independently.
> > > 
> > > Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
> > > Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
> > 
> > That all looks very reasonable now. The only remaining question is your SOB
> > chain. Who is the author of these patches? You or Maxime? If it's Maxime,
> > then the changelog misses a From: tag. If it's you then Maximes SOB is
> > bogus.
> 
> Actually Maxime wrote the main part of this driver and sent version 1 and 2 of
> the series. After Linus W. reviews, rework was required to use hierarchical
> domain. According to Maxime, I coded the rework (adaptation to hierarchical
> domain) and sent other version of the series.

So I replace Maximes SOB with Originally-by: Does that apply to all four
patches?

Thanks,

	tglx

[PATCH v6 2/4] drivers: irqchip: Add STM32 external interrupts support

[Maxime Coquelin]

2016-09-21 9:50 GMT+02:00 Thomas Gleixner <tglx@linutronix.de>:
> On Wed, 21 Sep 2016, Alexandre Torgue wrote:
>
>> Hi Thomas,
>>
>> On 09/20/2016 10:16 PM, Thomas Gleixner wrote:
>> > Alexandre,
>> >
>> > On Tue, 20 Sep 2016, Alexandre TORGUE wrote:
>> >
>> > > The STM32 external interrupt controller consists of edge detectors that
>> > > generate interrupts requests or wake-up events.
>> > >
>> > > Each line can be independently configured as interrupt or wake-up source,
>> > > and triggers either on rising, falling or both edges. Each line can also
>> > > be masked independently.
>> > >
>> > > Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
>> > > Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
>> >
>> > That all looks very reasonable now. The only remaining question is your SOB
>> > chain. Who is the author of these patches? You or Maxime? If it's Maxime,
>> > then the changelog misses a From: tag. If it's you then Maximes SOB is
>> > bogus.
>>
>> Actually Maxime wrote the main part of this driver and sent version 1 and 2 of
>> the series. After Linus W. reviews, rework was required to use hierarchical
>> domain. According to Maxime, I coded the rework (adaptation to hierarchical
>> domain) and sent other version of the series.
>
> So I replace Maximes SOB with Originally-by: Does that apply to all four
> patches?
Yes, that's fine.
Alex did a lot of rework on this series, he deserves the SoB.

Thanks,
Maxime

[PATCH v6 3/4] ARM: STM32: Select external interrupts controller

[Alexandre TORGUE]

Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 2d601d7..157cea9 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -877,6 +877,7 @@ config ARCH_STM32
 	select CLKSRC_STM32
 	select PINCTRL
 	select RESET_CONTROLLER
+	select STM32_EXTI
 	help
 	  Support for STMicroelectronics STM32 processors.
 
-- 
1.9.1

[PATCH v6 4/4] ARM: dts: Add EXTI controller node to stm32f429

[Alexandre TORGUE]

Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>

diff --git a/arch/arm/boot/dts/stm32f429.dtsi b/arch/arm/boot/dts/stm32f429.dtsi
index 35df462..1a189d4 100644
--- a/arch/arm/boot/dts/stm32f429.dtsi
+++ b/arch/arm/boot/dts/stm32f429.dtsi
@@ -176,6 +176,14 @@
 			reg = <0x40013800 0x400>;
 		};
 
+		exti: interrupt-controller at 40013c00 {
+			compatible = "st,stm32-exti";
+			interrupt-controller;
+			#interrupt-cells = <2>;
+			reg = <0x40013C00 0x400>;
+			interrupts = <1>, <2>, <3>, <6>, <7>, <8>, <9>, <10>, <23>, <40>, <41>, <42>, <62>, <76>;
+		};
+
 		pin-controller {
 			#address-cells = <1>;
 			#size-cells = <1>;
-- 
1.9.1