Commit 29b5357d authored by Rabin Vincent's avatar Rabin Vincent Committed by Linus Walleij
Browse files

gpio: etraxfs: add interrupt support 



On ETRAX FS, all pins on the first port (and only the first port) have
interrupt support.

On ARTPEC-3, all pins on all ports have interrupt support.  However,
there are only eight interrupts.  Each of the interrupts is associated
with a group of pins and for each interrupt the one pin from the group
which will trigger it can be selected.

Signed-off-by: default avatarRabin Vincent <rabin@rab.in>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent 8b67a1f0

drivers/gpio/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -171,6 +171,7 @@ config GPIO_ETRAXFS 
	depends on CRIS || COMPILE_TEST

	depends on OF

	select GPIO_GENERIC

	select GPIOLIB_IRQCHIP

	help

	  Say yes here to support the GPIO controller on Axis ETRAX FS SoCs.

drivers/gpio/gpio-etraxfs.c

+252 −7
Original line number Diff line number Diff line 
#include <linux/kernel.h>

#include <linux/init.h>

#include <linux/gpio.h>

#include <linux/gpio/driver.h>

#include <linux/of_gpio.h>

#include <linux/io.h>

#include <linux/interrupt.h>

#include <linux/platform_device.h>

#include <linux/basic_mmio_gpio.h>
@@ -13,6 +15,7 @@ 
#define ETRAX_FS_rw_intr_mask	16

#define ETRAX_FS_rw_ack_intr	20

#define ETRAX_FS_r_intr		24

#define ETRAX_FS_r_masked_intr	28

#define ETRAX_FS_rw_pb_dout	32

#define ETRAX_FS_r_pb_din	36

#define ETRAX_FS_rw_pb_oe	40
@@ -36,6 +39,37 @@ 
#define ARTPEC3_rw_pc_dout	92

#define ARTPEC3_rw_pc_oe	96

#define ARTPEC3_r_pd_din	116

#define ARTPEC3_rw_intr_cfg	120

#define ARTPEC3_rw_intr_pins	124

#define ARTPEC3_rw_intr_mask	128

#define ARTPEC3_rw_ack_intr	132

#define ARTPEC3_r_masked_intr	140



#define GIO_CFG_OFF		0

#define GIO_CFG_HI		1

#define GIO_CFG_LO		2

#define GIO_CFG_SET		3

#define GIO_CFG_POSEDGE		5

#define GIO_CFG_NEGEDGE		6

#define GIO_CFG_ANYEDGE		7



struct etraxfs_gpio_info;



struct etraxfs_gpio_block {

	spinlock_t lock;

	u32 mask;

	u32 cfg;

	u32 pins;

	unsigned int group[8];



	void __iomem *regs;

	const struct etraxfs_gpio_info *info;

};



struct etraxfs_gpio_chip {

	struct bgpio_chip bgc;

	struct etraxfs_gpio_block *block;

};



struct etraxfs_gpio_port {

	const char *label;
@@ -48,6 +82,12 @@ struct etraxfs_gpio_port { 
struct etraxfs_gpio_info {

	unsigned int num_ports;

	const struct etraxfs_gpio_port *ports;



	unsigned int rw_ack_intr;

	unsigned int rw_intr_mask;

	unsigned int rw_intr_cfg;

	unsigned int rw_intr_pins;

	unsigned int r_masked_intr;

};



static const struct etraxfs_gpio_port etraxfs_gpio_etraxfs_ports[] = {
@@ -91,6 +131,10 @@ static const struct etraxfs_gpio_port etraxfs_gpio_etraxfs_ports[] = { 
static const struct etraxfs_gpio_info etraxfs_gpio_etraxfs = {

	.num_ports = ARRAY_SIZE(etraxfs_gpio_etraxfs_ports),

	.ports = etraxfs_gpio_etraxfs_ports,

	.rw_ack_intr	= ETRAX_FS_rw_ack_intr,

	.rw_intr_mask	= ETRAX_FS_rw_intr_mask,

	.rw_intr_cfg	= ETRAX_FS_rw_intr_cfg,

	.r_masked_intr	= ETRAX_FS_r_masked_intr,

};



static const struct etraxfs_gpio_port etraxfs_gpio_artpec3_ports[] = {
@@ -125,8 +169,18 @@ static const struct etraxfs_gpio_port etraxfs_gpio_artpec3_ports[] = { 
static const struct etraxfs_gpio_info etraxfs_gpio_artpec3 = {

	.num_ports = ARRAY_SIZE(etraxfs_gpio_artpec3_ports),

	.ports = etraxfs_gpio_artpec3_ports,

	.rw_ack_intr	= ARTPEC3_rw_ack_intr,

	.rw_intr_mask	= ARTPEC3_rw_intr_mask,

	.rw_intr_cfg	= ARTPEC3_rw_intr_cfg,

	.r_masked_intr	= ARTPEC3_r_masked_intr,

	.rw_intr_pins	= ARTPEC3_rw_intr_pins,

};



static unsigned int etraxfs_gpio_chip_to_port(struct gpio_chip *gc)

{

	return gc->label[0] - 'A';

}



static int etraxfs_gpio_of_xlate(struct gpio_chip *gc,

			       const struct of_phandle_args *gpiospec,

			       u32 *flags)
@@ -135,7 +189,7 @@ static int etraxfs_gpio_of_xlate(struct gpio_chip *gc, 
	 * Port numbers are A to E, and the properties are integers, so we

	 * specify them as 0xA - 0xE.

	 */

	if (gc->label[0] - 'A' + 0xA != gpiospec->args[2])

	if (etraxfs_gpio_chip_to_port(gc) + 0xA != gpiospec->args[2])

		return -EINVAL;



	return of_gpio_simple_xlate(gc, gpiospec, flags);
@@ -153,13 +207,159 @@ static const struct of_device_id etraxfs_gpio_of_table[] = { 
	{},

};



static unsigned int etraxfs_gpio_to_group_irq(unsigned int gpio)

{

	return gpio % 8;

}



static unsigned int etraxfs_gpio_to_group_pin(struct etraxfs_gpio_chip *chip,

					      unsigned int gpio)

{

	return 4 * etraxfs_gpio_chip_to_port(&chip->bgc.gc) + gpio / 8;

}



static void etraxfs_gpio_irq_ack(struct irq_data *d)

{

	struct etraxfs_gpio_chip *chip = irq_data_get_irq_chip_data(d);

	struct etraxfs_gpio_block *block = chip->block;

	unsigned int grpirq = etraxfs_gpio_to_group_irq(d->hwirq);



	writel(BIT(grpirq), block->regs + block->info->rw_ack_intr);

}



static void etraxfs_gpio_irq_mask(struct irq_data *d)

{

	struct etraxfs_gpio_chip *chip = irq_data_get_irq_chip_data(d);

	struct etraxfs_gpio_block *block = chip->block;

	unsigned int grpirq = etraxfs_gpio_to_group_irq(d->hwirq);



	spin_lock(&block->lock);

	block->mask &= ~BIT(grpirq);

	writel(block->mask, block->regs + block->info->rw_intr_mask);

	spin_unlock(&block->lock);

}



static void etraxfs_gpio_irq_unmask(struct irq_data *d)

{

	struct etraxfs_gpio_chip *chip = irq_data_get_irq_chip_data(d);

	struct etraxfs_gpio_block *block = chip->block;

	unsigned int grpirq = etraxfs_gpio_to_group_irq(d->hwirq);



	spin_lock(&block->lock);

	block->mask |= BIT(grpirq);

	writel(block->mask, block->regs + block->info->rw_intr_mask);

	spin_unlock(&block->lock);

}



static int etraxfs_gpio_irq_set_type(struct irq_data *d, u32 type)

{

	struct etraxfs_gpio_chip *chip = irq_data_get_irq_chip_data(d);

	struct etraxfs_gpio_block *block = chip->block;

	unsigned int grpirq = etraxfs_gpio_to_group_irq(d->hwirq);

	u32 cfg;



	switch (type) {

	case IRQ_TYPE_EDGE_RISING:

		cfg = GIO_CFG_POSEDGE;

		break;

	case IRQ_TYPE_EDGE_FALLING:

		cfg = GIO_CFG_NEGEDGE;

		break;

	case IRQ_TYPE_EDGE_BOTH:

		cfg = GIO_CFG_ANYEDGE;

		break;

	case IRQ_TYPE_LEVEL_LOW:

		cfg = GIO_CFG_LO;

		break;

	case IRQ_TYPE_LEVEL_HIGH:

		cfg = GIO_CFG_HI;

		break;

	default:

		return -EINVAL;

	}



	spin_lock(&block->lock);

	block->cfg &= ~(0x7 << (grpirq * 3));

	block->cfg |= (cfg << (grpirq * 3));

	writel(block->cfg, block->regs + block->info->rw_intr_cfg);

	spin_unlock(&block->lock);



	return 0;

}



static int etraxfs_gpio_irq_request_resources(struct irq_data *d)

{

	struct etraxfs_gpio_chip *chip = irq_data_get_irq_chip_data(d);

	struct etraxfs_gpio_block *block = chip->block;

	unsigned int grpirq = etraxfs_gpio_to_group_irq(d->hwirq);

	int ret = -EBUSY;



	spin_lock(&block->lock);

	if (block->group[grpirq])

		goto out;



	ret = gpiochip_lock_as_irq(&chip->bgc.gc, d->hwirq);

	if (ret)

		goto out;



	block->group[grpirq] = d->irq;

	if (block->info->rw_intr_pins) {

		unsigned int pin = etraxfs_gpio_to_group_pin(chip, d->hwirq);



		block->pins &= ~(0xf << (grpirq * 4));

		block->pins |= (pin << (grpirq * 4));



		writel(block->pins, block->regs + block->info->rw_intr_pins);

	}



out:

	spin_unlock(&block->lock);

	return ret;

}



static void etraxfs_gpio_irq_release_resources(struct irq_data *d)

{

	struct etraxfs_gpio_chip *chip = irq_data_get_irq_chip_data(d);

	struct etraxfs_gpio_block *block = chip->block;

	unsigned int grpirq = etraxfs_gpio_to_group_irq(d->hwirq);



	spin_lock(&block->lock);

	block->group[grpirq] = 0;

	gpiochip_unlock_as_irq(&chip->bgc.gc, d->hwirq);

	spin_unlock(&block->lock);

}



static struct irq_chip etraxfs_gpio_irq_chip = {

	.name		= "gpio-etraxfs",

	.irq_ack	= etraxfs_gpio_irq_ack,

	.irq_mask	= etraxfs_gpio_irq_mask,

	.irq_unmask	= etraxfs_gpio_irq_unmask,

	.irq_set_type	= etraxfs_gpio_irq_set_type,

	.irq_request_resources = etraxfs_gpio_irq_request_resources,

	.irq_release_resources = etraxfs_gpio_irq_release_resources,

};



static irqreturn_t etraxfs_gpio_interrupt(int irq, void *dev_id)

{

	struct etraxfs_gpio_block *block = dev_id;

	unsigned long intr = readl(block->regs + block->info->r_masked_intr);

	int bit;



	for_each_set_bit(bit, &intr, 8)

		generic_handle_irq(block->group[bit]);



	return IRQ_RETVAL(intr & 0xff);

}



static int etraxfs_gpio_probe(struct platform_device *pdev)

{

	struct device *dev = &pdev->dev;

	const struct etraxfs_gpio_info *info;

	const struct of_device_id *match;

	struct bgpio_chip *chips;

	struct resource *res;

	struct etraxfs_gpio_block *block;

	struct etraxfs_gpio_chip *chips;

	struct resource *res, *irq;

	bool allportsirq = false;

	void __iomem *regs;

	int ret;

	int i;
@@ -179,14 +379,44 @@ static int etraxfs_gpio_probe(struct platform_device *pdev) 
	if (!chips)

		return -ENOMEM;



	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);

	if (!irq)

		return -EINVAL;



	block = devm_kzalloc(dev, sizeof(*block), GFP_KERNEL);

	if (!block)

		return -ENOMEM;



	spin_lock_init(&block->lock);



	block->regs = regs;

	block->info = info;



	writel(0, block->regs + info->rw_intr_mask);

	writel(0, block->regs + info->rw_intr_cfg);

	if (info->rw_intr_pins) {

		allportsirq = true;

		writel(0, block->regs + info->rw_intr_pins);

	}



	ret = devm_request_irq(dev, irq->start, etraxfs_gpio_interrupt,

			       IRQF_SHARED, dev_name(dev), block);

	if (ret) {

		dev_err(dev, "Unable to request irq %d\n", ret);

		return ret;

	}



	for (i = 0; i < info->num_ports; i++) {

		struct bgpio_chip *bgc = &chips[i];

		struct etraxfs_gpio_chip *chip = &chips[i];

		struct bgpio_chip *bgc = &chip->bgc;

		const struct etraxfs_gpio_port *port = &info->ports[i];

		unsigned long flags = BGPIOF_READ_OUTPUT_REG_SET;

		void __iomem *dat = regs + port->din;

		void __iomem *set = regs + port->dout;

		void __iomem *dirout = regs + port->oe;



		chip->block = block;



		if (dirout == set) {

			dirout = set = NULL;

			flags = BGPIOF_NO_OUTPUT;
@@ -195,8 +425,11 @@ static int etraxfs_gpio_probe(struct platform_device *pdev) 
		ret = bgpio_init(bgc, dev, 4,

				 dat, set, NULL, dirout, NULL,

				 flags);

		if (ret)

			return ret;

		if (ret) {

			dev_err(dev, "Unable to init port %s\n",

				port->label);

			continue;

		}



		bgc->gc.ngpio = port->ngpio;

		bgc->gc.label = port->label;
@@ -206,9 +439,21 @@ static int etraxfs_gpio_probe(struct platform_device *pdev) 
		bgc->gc.of_xlate = etraxfs_gpio_of_xlate;



		ret = gpiochip_add(&bgc->gc);

		if (ret)

		if (ret) {

			dev_err(dev, "Unable to register port %s\n",

				bgc->gc.label);

			continue;

		}



		if (i > 0 && !allportsirq)

			continue;



		ret = gpiochip_irqchip_add(&bgc->gc, &etraxfs_gpio_irq_chip, 0,

					   handle_level_irq, IRQ_TYPE_NONE);

		if (ret) {

			dev_err(dev, "Unable to add irqchip to port %s\n",

				bgc->gc.label);

		}

	}



	return 0;

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