[PATCH v5 1/3] gpio: xgene: Enable X-Gene standby GPIO as interrupt controller

Quan Nguyen
2016-01-29T04:28:53Z

Enable X-Gene standby GPIO controller as interrupt controller to provide
its own resources. This avoids ambiguity where GIC interrupt resource is
use as X-Gene standby GPIO interrupt resource in user driver.

Signed-off-by: Y Vo <yvo@apm.com>
Signed-off-by: Quan Nguyen <qnguyen@apm.com>
---
drivers/gpio/gpio-xgene-sb.c | 275 ++++++++++++++++++++++++++++++++++++++-----
1 file changed, 243 insertions(+), 32 deletions(-)

diff --git a/drivers/gpio/gpio-xgene-sb.c b/drivers/gpio/gpio-xgene-sb.c
index 282004d..026da90 100644
--- a/drivers/gpio/gpio-xgene-sb.c
+++ b/drivers/gpio/gpio-xgene-sb.c
@@ -2,8 +2,9 @@
* AppliedMicro X-Gene SoC GPIO-Standby Driver
*
* Copyright (c) 2014, Applied Micro Circuits Corporation
- * Author: Tin Huynh <tnhuynh@apm.com>.
- * Y Vo <yvo@apm.com>.
+ * Author: Tin Huynh <tnhuynh@apm.com>.
+ * Y Vo <yvo@apm.com>.
+ * Quan Nguyen <qnguyen@apm.com>.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
@@ -28,9 +29,14 @@

#include "gpiolib.h"

-#define XGENE_MAX_GPIO_DS 22
-#define XGENE_MAX_GPIO_DS_IRQ 6
+/* Common property names */
+#define XGENE_NIRQ_PROPERTY "apm,nr-irqs"
+#define XGENE_NGPIO_PROPERTY "apm,nr-gpios"
+#define XGENE_IRQ_START_PROPERTY "apm,irq-start"

+#define XGENE_DFLT_MAX_NGPIO 22
+#define XGENE_DFLT_MAX_NIRQ 6
+#define XGENE_DFLT_IRQ_START_PIN 8
#define GPIO_MASK(x) (1U << ((x) % 32))

#define MPA_GPIO_INT_LVL 0x0290
@@ -39,19 +45,32 @@
#define MPA_GPIO_IN_ADDR 0x02a4
#define MPA_GPIO_SEL_LO 0x0294

+#define GPIO_INT_LEVEL_H 0x000001
+#define GPIO_INT_LEVEL_L 0x000000
+
/**
* struct xgene_gpio_sb - GPIO-Standby private data structure.
* @gc: memory-mapped GPIO controllers.
- * @irq: Mapping GPIO pins and interrupt number
- * nirq: Number of GPIO pins that supports interrupt
+ * @regs: GPIO register base offset
+ * @irq_domain: GPIO interrupt domain
+ * @irq_start: GPIO pin that start support interrupt
+ * @nirq: Number of GPIO pins that supports interrupt
+ * @parent_irq_base: Start parent HWIRQ
*/
struct xgene_gpio_sb {
struct gpio_chip gc;
- u32 *irq;
- u32 nirq;
+ void __iomem *regs;
+ struct irq_domain *irq_domain;
+ u16 irq_start;
+ u16 nirq;
+ u16 parent_irq_base;
};

-static void xgene_gpio_set_bit(struct gpio_chip *gc, void __iomem *reg, u32 gpio, int val)
+#define HWIRQ_TO_GPIO(priv, hwirq) ((hwirq) + (priv)->irq_start)
+#define GPIO_TO_HWIRQ(priv, gpio) ((gpio) - (priv)->irq_start)
+
+static void xgene_gpio_set_bit(struct gpio_chip *gc,
+ void __iomem *reg, u32 gpio, int val)
{
u32 data;

@@ -63,23 +82,180 @@ static void xgene_gpio_set_bit(struct gpio_chip *gc, void __iomem *reg, u32 gpio
gc->write_reg(reg, data);
}

-static int apm_gpio_sb_to_irq(struct gpio_chip *gc, u32 gpio)
+static int xgene_gpio_sb_irq_set_type(struct irq_data *d, unsigned int type)
+{
+ struct xgene_gpio_sb *priv = irq_data_get_irq_chip_data(d);
+ int gpio = HWIRQ_TO_GPIO(priv, d->hwirq);
+ int lvl_type = GPIO_INT_LEVEL_H;
+
+ switch (type & IRQ_TYPE_SENSE_MASK) {
+ case IRQ_TYPE_EDGE_RISING:
+ case IRQ_TYPE_LEVEL_HIGH:
+ lvl_type = GPIO_INT_LEVEL_H;
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ case IRQ_TYPE_LEVEL_LOW:
+ lvl_type = GPIO_INT_LEVEL_L;
+ break;
+ default:
+ break;
+ }
+
+ xgene_gpio_set_bit(&priv->gc, priv->regs + MPA_GPIO_SEL_LO,
+ gpio * 2, 1);
+ xgene_gpio_set_bit(&priv->gc, priv->regs + MPA_GPIO_INT_LVL,
+ d->hwirq, lvl_type);
+
+ /* Propagate IRQ type setting to parent */
+ if (type & IRQ_TYPE_EDGE_BOTH)
+ return irq_chip_set_type_parent(d, IRQ_TYPE_EDGE_RISING);
+ else
+ return irq_chip_set_type_parent(d, IRQ_TYPE_LEVEL_HIGH);
+}
+
+static void xgene_gpio_sb_irq_shutdown(struct irq_data *d)
+{
+ struct xgene_gpio_sb *priv = irq_data_get_irq_chip_data(d);
+
+ gpiochip_unlock_as_irq(&priv->gc, HWIRQ_TO_GPIO(priv, d->hwirq));
+}
+
+static struct irq_chip xgene_gpio_sb_irq_chip = {
+ .name = "sbgpio",
+ .irq_ack = irq_chip_ack_parent,
+ .irq_eoi = irq_chip_eoi_parent,
+ .irq_mask = irq_chip_mask_parent,
+ .irq_unmask = irq_chip_unmask_parent,
+ .irq_set_type = xgene_gpio_sb_irq_set_type,
+ .irq_shutdown = xgene_gpio_sb_irq_shutdown,
+};
+
+static int xgene_gpio_sb_to_irq(struct gpio_chip *gc, u32 gpio)
{
struct xgene_gpio_sb *priv = gpiochip_get_data(gc);
+ struct irq_fwspec fwspec;
+
+ if ((gpio < priv->irq_start) ||
+ (gpio > HWIRQ_TO_GPIO(priv, priv->nirq)))
+ return -ENXIO;
+
+ if (gc->parent->of_node)
+ fwspec.fwnode = of_node_to_fwnode(gc->parent->of_node);
+ else
+ fwspec.fwnode = gc->parent->fwnode;
+ fwspec.param_count = 2;
+ fwspec.param[0] = GPIO_TO_HWIRQ(priv, gpio);
+ fwspec.param[1] = IRQ_TYPE_NONE;
+ return irq_create_fwspec_mapping(&fwspec);
+}
+
+static void xgene_gpio_sb_domain_activate(struct irq_domain *d,
+ struct irq_data *irq_data)
+{
+ struct xgene_gpio_sb *priv = d->host_data;
+ u32 gpio = HWIRQ_TO_GPIO(priv, irq_data->hwirq);
+
+ if (gpiochip_lock_as_irq(&priv->gc, gpio)) {
+ dev_err(priv->gc.parent,
+ "Unable to configure XGene GPIO standby pin %d as IRQ\n",
+ gpio);
+ return;
+ }
+
+ xgene_gpio_set_bit(&priv->gc, priv->regs + MPA_GPIO_SEL_LO,
+ gpio * 2, 1);
+}
+
+static void xgene_gpio_sb_domain_deactivate(struct irq_domain *d,
+ struct irq_data *irq_data)
+{
+ struct xgene_gpio_sb *priv = d->host_data;
+ u32 gpio = HWIRQ_TO_GPIO(priv, irq_data->hwirq);
+
+ gpiochip_unlock_as_irq(&priv->gc, gpio);
+ xgene_gpio_set_bit(&priv->gc, priv->regs + MPA_GPIO_SEL_LO,
+ gpio * 2, 0);
+}

- if (priv->irq[gpio])
- return priv->irq[gpio];
+static int xgene_gpio_sb_domain_translate(struct irq_domain *d,
+ struct irq_fwspec *fwspec,
+ unsigned long *hwirq,
+ unsigned int *type)
+{
+ struct xgene_gpio_sb *priv = d->host_data;
+
+ if ((fwspec->param_count != 2) ||
+ (fwspec->param[0] >= priv->nirq))
+ return -EINVAL;
+ *hwirq = fwspec->param[0];
+ *type = fwspec->param[1];
+ return 0;
+}
+
+static int xgene_gpio_sb_domain_alloc(struct irq_domain *domain,
+ unsigned int virq,
+ unsigned int nr_irqs, void *data)
+{
+ struct irq_fwspec *fwspec = data;
+ struct irq_fwspec parent_fwspec;
+ struct xgene_gpio_sb *priv = domain->host_data;
+ irq_hw_number_t hwirq;
+ unsigned int i;
+
+ hwirq = fwspec->param[0];
+ for (i = 0; i < nr_irqs; i++)
+ irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
+ &xgene_gpio_sb_irq_chip, priv);
+
+ if (is_of_node(domain->parent->fwnode)) {
+ parent_fwspec.fwnode = domain->parent->fwnode;
+ parent_fwspec.param_count = 3;
+ parent_fwspec.param[0] = 0;/* SPI */
+ /* Skip SGIs and PPIs*/
+ parent_fwspec.param[1] = hwirq + priv->parent_irq_base - 32;
+ parent_fwspec.param[2] = fwspec->param[1];
+ } else if (is_fwnode_irqchip(domain->parent->fwnode)) {
+ parent_fwspec.fwnode = domain->parent->fwnode;
+ parent_fwspec.param_count = 2;
+ parent_fwspec.param[0] = hwirq + priv->parent_irq_base;
+ parent_fwspec.param[1] = fwspec->param[1];
+ } else
+ return -EINVAL;

- return -ENXIO;
+ return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
+ &parent_fwspec);
}

+static void xgene_gpio_sb_domain_free(struct irq_domain *domain,
+ unsigned int virq,
+ unsigned int nr_irqs)
+{
+ struct irq_data *d;
+ unsigned int i;
+
+ for (i = 0; i < nr_irqs; i++) {
+ d = irq_domain_get_irq_data(domain, virq + i);
+ irq_domain_reset_irq_data(d);
+ }
+}
+
+static const struct irq_domain_ops xgene_gpio_sb_domain_ops = {
+ .translate = xgene_gpio_sb_domain_translate,
+ .alloc = xgene_gpio_sb_domain_alloc,
+ .free = xgene_gpio_sb_domain_free,
+ .activate = xgene_gpio_sb_domain_activate,
+ .deactivate = xgene_gpio_sb_domain_deactivate,
+};
+
static int xgene_gpio_sb_probe(struct platform_device *pdev)
{
struct xgene_gpio_sb *priv;
- u32 ret, i;
- u32 default_lines[] = {0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D};
+ u32 ret;
struct resource *res;
void __iomem *regs;
+ struct irq_domain *parent_domain = NULL;
+ struct fwnode_handle *fwnode;
+ u32 val32;

priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
@@ -90,6 +266,18 @@ static int xgene_gpio_sb_probe(struct platform_device *pdev)
if (IS_ERR(regs))
return PTR_ERR(regs);

+ priv->regs = regs;
+
+ ret = platform_get_irq(pdev, 0);
+ if (ret > 0) {
+ priv->parent_irq_base = irq_get_irq_data(ret)->hwirq;
+ parent_domain = irq_get_irq_data(ret)->domain;
+ }
+ if (!parent_domain) {
+ dev_err(&pdev->dev, "unable to obtain parent domain\n");
+ return -ENODEV;
+ }
+
ret = bgpio_init(&priv->gc, &pdev->dev, 4,
regs + MPA_GPIO_IN_ADDR,
regs + MPA_GPIO_OUT_ADDR, NULL,
@@ -97,30 +285,51 @@ static int xgene_gpio_sb_probe(struct platform_device *pdev)
if (ret)
return ret;

- priv->gc.to_irq = apm_gpio_sb_to_irq;
- priv->gc.ngpio = XGENE_MAX_GPIO_DS;
+ priv->gc.to_irq = xgene_gpio_sb_to_irq;

- priv->nirq = XGENE_MAX_GPIO_DS_IRQ;
+ /* Retrieve start irq pin, use default if property not found */
+ priv->irq_start = XGENE_DFLT_IRQ_START_PIN;
+ if (!device_property_read_u32(&pdev->dev,
+ XGENE_IRQ_START_PROPERTY, &val32))
+ priv->irq_start = val32;

- priv->irq = devm_kzalloc(&pdev->dev, sizeof(u32) * XGENE_MAX_GPIO_DS,
- GFP_KERNEL);
- if (!priv->irq)
- return -ENOMEM;
+ /* Retrieve number irqs, use default if property not found */
+ priv->nirq = XGENE_DFLT_MAX_NIRQ;
+ if (!device_property_read_u32(&pdev->dev, XGENE_NIRQ_PROPERTY, &val32))
+ priv->nirq = val32;

- for (i = 0; i < priv->nirq; i++) {
- priv->irq[default_lines[i]] = platform_get_irq(pdev, i);
- xgene_gpio_set_bit(&priv->gc, regs + MPA_GPIO_SEL_LO,
- default_lines[i] * 2, 1);
- xgene_gpio_set_bit(&priv->gc, regs + MPA_GPIO_INT_LVL, i, 1);
- }
+ /* Retrieve number gpio, use default if property not found */
+ priv->gc.ngpio = XGENE_DFLT_MAX_NGPIO;
+ if (!device_property_read_u32(&pdev->dev, XGENE_NGPIO_PROPERTY, &val32))
+ priv->gc.ngpio = val32;
+
+ dev_info(&pdev->dev, "Support %d gpios, %d irqs start from pin %d\n",
+ priv->gc.ngpio, priv->nirq, priv->irq_start);

platform_set_drvdata(pdev, priv);

- ret = gpiochip_add_data(&priv->gc, priv);
- if (ret)
- dev_err(&pdev->dev, "failed to register X-Gene GPIO Standby driver\n");
+ if (pdev->dev.of_node)
+ fwnode = of_node_to_fwnode(pdev->dev.of_node);
else
- dev_info(&pdev->dev, "X-Gene GPIO Standby driver registered\n");
+ fwnode = pdev->dev.fwnode;
+
+ priv->irq_domain = irq_domain_create_hierarchy(parent_domain,
+ 0, priv->nirq, fwnode,
+ &xgene_gpio_sb_domain_ops, priv);
+ if (!priv->irq_domain)
+ return -ENODEV;
+
+ priv->gc.irqdomain = priv->irq_domain;
+
+ ret = gpiochip_add_data(&priv->gc, priv);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "failed to register X-Gene GPIO Standby driver\n");
+ irq_domain_remove(priv->irq_domain);
+ return ret;
+ }
+
+ dev_info(&pdev->dev, "X-Gene GPIO Standby driver registered\n");

if (priv->nirq > 0) {
/* Register interrupt handlers for gpio signaled acpi events */
@@ -138,6 +347,8 @@ static int xgene_gpio_sb_remove(struct platform_device *pdev)
acpi_gpiochip_free_interrupts(&priv->gc);
}

+ irq_domain_remove(priv->irq_domain);
+
gpiochip_remove(&priv->gc);
return 0;
}
--
1.7.12.4