[PATCH 05/10] gpio: Introduce SAM gpio driver

From: Pantelis Antoniou
Date: Fri Oct 07 2016 - 11:22:17 EST


From: Guenter Roeck <groeck@xxxxxxxxxxx>

The SAM GPIO IP block is present in the Juniper PTX series
of routers as part of the SAM FPGA.

Signed-off-by: Georgi Vlaev <gvlaev@xxxxxxxxxxx>
Signed-off-by: Guenter Roeck <groeck@xxxxxxxxxxx>
Signed-off-by: Rajat Jain <rajatjain@xxxxxxxxxxx>
[Ported from Juniper kernel]
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@xxxxxxxxxxxx>
---
drivers/gpio/Kconfig | 11 +
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-sam.c | 707 ++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 719 insertions(+)
create mode 100644 drivers/gpio/gpio-sam.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 9c91de6..c25dbe9 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -384,6 +384,17 @@ config GPIO_RCAR
help
Say yes here to support GPIO on Renesas R-Car SoCs.

+config GPIO_SAM
+ tristate "SAM FPGA GPIO"
+ depends on MFD_JUNIPER_SAM
+ default y if MFD_JUNIPER_SAM
+ help
+ This driver supports the GPIO interfaces on the SAM FPGA which is
+ present on the relevant Juniper platforms.
+
+ This driver can also be built as a module. If so, the module
+ will be called gpio-sam.
+
config GPIO_SPEAR_SPICS
bool "ST SPEAr13xx SPI Chip Select as GPIO support"
depends on PLAT_SPEAR
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index d397ea5..6691d8c 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -96,6 +96,7 @@ obj-$(CONFIG_GPIO_RC5T583) += gpio-rc5t583.o
obj-$(CONFIG_GPIO_RDC321X) += gpio-rdc321x.o
obj-$(CONFIG_GPIO_RCAR) += gpio-rcar.o
obj-$(CONFIG_ARCH_SA1100) += gpio-sa1100.o
+obj-$(CONFIG_GPIO_SAM) += gpio-sam.o
obj-$(CONFIG_GPIO_SCH) += gpio-sch.o
obj-$(CONFIG_GPIO_SCH311X) += gpio-sch311x.o
obj-$(CONFIG_GPIO_SODAVILLE) += gpio-sodaville.o
diff --git a/drivers/gpio/gpio-sam.c b/drivers/gpio/gpio-sam.c
new file mode 100644
index 0000000..5082050
--- /dev/null
+++ b/drivers/gpio/gpio-sam.c
@@ -0,0 +1,707 @@
+/*
+ * Copyright (C) 2012 - 2015 Juniper Networks
+ *
+ * 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 Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/irqdomain.h>
+#include <linux/errno.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/of_gpio.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/mfd/sam.h>
+
+/* gpio status/configuration */
+#define SAM_GPIO_NEG_EDGE (1 << 8)
+#define SAM_GPIO_NEG_EDGE_EN (1 << 7)
+#define SAM_GPIO_POS_EDGE (1 << 6)
+#define SAM_GPIO_POS_EDGE_EN (1 << 5)
+#define SAM_GPIO_BLINK (1 << 4)
+#define SAM_GPIO_OUT (1 << 3)
+#define SAM_GPIO_OUT_TS (1 << 2)
+#define SAM_GPIO_DEBOUNCE_EN (1 << 1)
+#define SAM_GPIO_IN (1 << 0)
+
+#define SAM_GPIO_BASE 0x1000
+
+#define SAM_MAX_NGPIO 512
+
+#define SAM_GPIO_ADDR(addr, nr) ((addr) + SAM_GPIO_BASE + (nr) * sizeof(u32))
+
+struct sam_gpio_irq_group {
+ int start; /* 1st gpio pin */
+ int count; /* # of pins in group */
+ int num_enabled; /* # of enabled interrupts */
+};
+
+/**
+ * struct sam_gpio - GPIO private data structure.
+ * @base: PCI base address of Memory mapped I/O register.
+ * @dev: Pointer to device structure.
+ * @gpio: Data for GPIO infrastructure.
+ * @gpio_base: 1st gpio pin
+ * @gpio_count: # of gpio pins
+ * @irq_lock: Lock used by interrupt subsystem
+ * @domain: Pointer to interrupt domain
+ * @irq: Interrupt # from parent
+ * @irq_high: Second interrupt # from parent
+ * (currently unused)
+ * @irq_group: Interrupt group descriptions
+ * (one group per interrupt bit)
+ * @irq_type: The interrupt type for each gpio pin
+ */
+struct sam_gpio {
+ void __iomem *base;
+ struct device *dev;
+ struct gpio_chip gpio;
+ int gpio_base;
+ int gpio_count;
+ struct mutex irq_lock;
+ struct irq_domain *domain;
+ int irq;
+ int irq_high;
+ struct sam_gpio_irq_group irq_group[18];
+ u8 irq_type[SAM_MAX_NGPIO];
+ struct sam_platform_data *pdata;
+ const char **names;
+ u32 *export_flags;
+};
+#define to_sam(chip) container_of((chip), struct sam_gpio, gpio)
+
+static void sam_gpio_bitop(struct sam_gpio *sam, unsigned int nr,
+ u32 bit, bool set)
+{
+ u32 reg;
+
+ reg = ioread32(SAM_GPIO_ADDR(sam->base, nr));
+ if (set)
+ reg |= bit;
+ else
+ reg &= ~bit;
+ iowrite32(reg, SAM_GPIO_ADDR(sam->base, nr));
+ ioread32(SAM_GPIO_ADDR(sam->base, nr));
+}
+
+static int sam_gpio_debounce(struct gpio_chip *chip, unsigned int nr,
+ unsigned int debounce)
+{
+ struct sam_gpio *sam = to_sam(chip);
+
+ sam_gpio_bitop(sam, nr, SAM_GPIO_DEBOUNCE_EN, debounce);
+
+ return 0;
+}
+
+static void sam_gpio_set(struct gpio_chip *chip, unsigned int nr, int val)
+{
+ struct sam_gpio *sam = to_sam(chip);
+
+ sam_gpio_bitop(sam, nr, SAM_GPIO_OUT, val);
+}
+
+static int sam_gpio_get(struct gpio_chip *chip, unsigned int nr)
+{
+ struct sam_gpio *sam = to_sam(chip);
+
+ return !!(ioread32(SAM_GPIO_ADDR(sam->base, nr)) & SAM_GPIO_IN);
+}
+
+static int sam_gpio_direction_output(struct gpio_chip *chip, unsigned int nr,
+ int val)
+{
+ struct sam_gpio *sam = to_sam(chip);
+
+ sam_gpio_bitop(sam, nr, SAM_GPIO_OUT, val);
+ sam_gpio_bitop(sam, nr, SAM_GPIO_OUT_TS, false);
+ return 0;
+}
+
+static int sam_gpio_direction_input(struct gpio_chip *chip, unsigned int nr)
+{
+ struct sam_gpio *sam = to_sam(chip);
+
+ sam_gpio_bitop(sam, nr, SAM_GPIO_OUT_TS, true);
+ sam_gpio_bitop(sam, nr, SAM_GPIO_OUT, false);
+ return 0;
+}
+
+static void sam_gpio_setup(struct sam_gpio *sam)
+{
+ struct gpio_chip *chip = &sam->gpio;
+
+ chip->parent = sam->dev;
+ chip->label = dev_name(sam->dev);
+ chip->owner = THIS_MODULE;
+ chip->direction_input = sam_gpio_direction_input;
+ chip->get = sam_gpio_get;
+ chip->direction_output = sam_gpio_direction_output;
+ chip->set = sam_gpio_set;
+ chip->set_debounce = sam_gpio_debounce;
+ chip->dbg_show = NULL;
+ chip->base = sam->gpio_base;
+ chip->ngpio = sam->gpio_count;
+#ifdef CONFIG_OF_GPIO
+ chip->of_node = sam->dev->of_node;
+#endif
+ chip->names = sam->names;
+}
+
+static int sam_of_get_exports(struct device *dev, struct sam_gpio *sam)
+{
+ struct device_node *child, *exports;
+ int err = 0;
+
+ if (dev->of_node == NULL)
+ return 0; /* No FDT node, we are done */
+
+ exports = of_get_child_by_name(dev->of_node, "gpio-exports");
+ if (exports == NULL)
+ return 0; /* No exports, we are done */
+
+ if (of_get_child_count(exports) == 0)
+ return 0; /* No children, we are done */
+
+ sam->names = devm_kzalloc(dev, sizeof(char *) * sam->gpio_count,
+ GFP_KERNEL);
+ if (sam->names == NULL) {
+ err = -ENOMEM;
+ goto error;
+ }
+ sam->export_flags =
+ devm_kzalloc(dev, sizeof(u32) * sam->gpio_count, GFP_KERNEL);
+ if (sam->export_flags == NULL) {
+ err = -ENOMEM;
+ goto error;
+ }
+ for_each_child_of_node(exports, child) {
+ const char *label;
+ u32 pin, flags;
+
+ label = of_get_property(child, "label", NULL) ? : child->name;
+ err = of_property_read_u32_index(child, "pin", 0, &pin);
+ if (err)
+ break;
+ if (pin >= sam->gpio_count) {
+ err = -EINVAL;
+ break;
+ }
+ err = of_property_read_u32_index(child, "pin", 1, &flags);
+ if (err)
+ break;
+ /*
+ * flags:
+ * GPIOF_DIR_IN bit 0=1
+ * GPIOF_DIR_OUT bit 0=0
+ * GPIOF_INIT_HIGH bit 1=1
+ * GPIOF_ACTIVE_LOW bit 2=1
+ * GPIOF_OPEN_DRAIN bit 3=1
+ * GPIOF_OPEN_SOURCE bit 4=1
+ * GPIOF_EXPORT bit 5=1
+ * GPIOF_EXPORT_CHANGEABLE bit 6=1
+ */
+ sam->names[pin] = label;
+ sam->export_flags[pin] = flags;
+ }
+error:
+ of_node_put(exports);
+ return err;
+}
+
+static int sam_gpio_of_init(struct device *dev, struct sam_gpio *sam)
+{
+ int err;
+ u32 val;
+ const u32 *igroup;
+ u32 group, start, count;
+ int i, iglen, ngpio;
+
+ if (of_have_populated_dt() && !dev->of_node) {
+ dev_err(dev, "No device node\n");
+ return -ENODEV;
+ }
+
+ err = of_property_read_u32(dev->of_node, "gpio-base", &val);
+ if (err)
+ val = -1;
+ sam->gpio_base = val;
+
+ err = of_property_read_u32(dev->of_node, "gpio-count", &val);
+ if (!err) {
+ if (val > SAM_MAX_NGPIO)
+ val = SAM_MAX_NGPIO;
+ sam->gpio_count = val;
+ }
+ /* validate gpio_count against chip data. Abort if chip data is bad. */
+ ngpio = ioread32(sam->base + 2 * sizeof(u32)) & 0xffff;
+ if (!ngpio || ngpio > SAM_MAX_NGPIO)
+ return -ENODEV;
+
+ if (!sam->gpio_count || sam->gpio_count > ngpio)
+ sam->gpio_count = ngpio;
+
+ igroup = of_get_property(dev->of_node, "gpio-interrupts", &iglen);
+ if (igroup) {
+ iglen /= sizeof(u32);
+ if (iglen < 3 || iglen % 3)
+ return -EINVAL;
+ iglen /= 3;
+ for (i = 0; i < iglen; i++) {
+ group = be32_to_cpu(igroup[i * 3]);
+ if (group >= ARRAY_SIZE(sam->irq_group))
+ return -EINVAL;
+ start = be32_to_cpu(igroup[i * 3 + 1]);
+ count = be32_to_cpu(igroup[i * 3 + 2]);
+ if (start >= sam->gpio_count || count == 0 ||
+ start + count > sam->gpio_count)
+ return -EINVAL;
+ sam->irq_group[group].start = start;
+ sam->irq_group[group].count = count;
+ }
+ }
+
+ err = sam_of_get_exports(dev, sam);
+ return err;
+}
+
+static int sam_gpio_pin_to_irq_bit(struct sam_gpio *sam, int pin)
+{
+ int bit;
+
+ for (bit = 0; bit < ARRAY_SIZE(sam->irq_group); bit++) {
+ struct sam_gpio_irq_group *irq_group = &sam->irq_group[bit];
+
+ if (irq_group->count &&
+ pin >= irq_group->start &&
+ pin <= irq_group->start + irq_group->count)
+ return bit;
+ }
+ return -EINVAL;
+}
+
+static bool sam_gpio_irq_handle_group(struct sam_gpio *sam,
+ struct sam_gpio_irq_group *irq_group)
+{
+ unsigned int virq = 0;
+ bool handled = false;
+ bool repeat;
+ int i;
+
+ /* no irq_group for the interrupt bit */
+ if (!irq_group->count)
+ return false;
+
+ WARN_ON(irq_group->num_enabled == 0);
+ do {
+ repeat = false;
+ for (i = 0; i < irq_group->count; i++) {
+ int pin = irq_group->start + i;
+ bool low, high;
+ u32 regval;
+ u8 type;
+
+ regval = ioread32(SAM_GPIO_ADDR(sam->base, pin));
+ /*
+ * write back status to clear POS_EDGE and NEG_EDGE
+ * status for this GPIO pin (status bits are
+ * clear-on-one). This is necessary to clear the
+ * high level interrupt status.
+ * Also consider the interrupt to be handled in that
+ * case, even if there is no taker.
+ */
+ if (regval & (SAM_GPIO_POS_EDGE | SAM_GPIO_NEG_EDGE)) {
+ iowrite32(regval,
+ SAM_GPIO_ADDR(sam->base, pin));
+ ioread32(SAM_GPIO_ADDR(sam->base, pin));
+ handled = true;
+ }
+
+ /*
+ * Check if the pin changed its state.
+ * If it did, and if the expected condition applies,
+ * generate a virtual interrupt.
+ * A pin can only generate an interrupt if
+ * - interrupts are enabled for it
+ * - it is configured as input
+ */
+
+ if (!sam->irq_type[pin])
+ continue;
+ if (!(regval & SAM_GPIO_OUT_TS))
+ continue;
+
+ high = regval & (SAM_GPIO_IN | SAM_GPIO_POS_EDGE);
+ low = !(regval & SAM_GPIO_IN) ||
+ (regval & SAM_GPIO_NEG_EDGE);
+ type = sam->irq_type[pin];
+ if (((type & IRQ_TYPE_EDGE_RISING) &&
+ (regval & SAM_GPIO_POS_EDGE)) ||
+ ((type & IRQ_TYPE_EDGE_FALLING) &&
+ (regval & SAM_GPIO_NEG_EDGE)) ||
+ ((type & IRQ_TYPE_LEVEL_LOW) && low) ||
+ ((type & IRQ_TYPE_LEVEL_HIGH) && high)) {
+ virq = irq_find_mapping(sam->domain, pin);
+ handle_nested_irq(virq);
+ if (type & (IRQ_TYPE_LEVEL_LOW
+ | IRQ_TYPE_LEVEL_HIGH))
+ repeat = true;
+ }
+ }
+ schedule();
+ } while (repeat);
+
+ return handled;
+}
+
+static irqreturn_t sam_gpio_irq_handler(int irq, void *data)
+{
+ struct sam_gpio *sam = data;
+ struct sam_platform_data *pdata = sam->pdata;
+ irqreturn_t ret = IRQ_NONE;
+ bool handled;
+ u32 status;
+
+ do {
+ handled = false;
+ status = pdata->irq_status(sam->dev->parent, SAM_IRQ_GPIO,
+ sam->irq);
+ pdata->irq_status_clear(sam->dev->parent, SAM_IRQ_GPIO,
+ sam->irq, status);
+ while (status) {
+ unsigned int bit;
+
+ bit = __ffs(status);
+ status &= ~(1 << bit);
+ handled =
+ sam_gpio_irq_handle_group(sam, &sam->irq_group[bit]);
+ if (handled)
+ ret = IRQ_HANDLED;
+ }
+ } while (handled);
+
+ return ret;
+}
+
+static int sam_gpio_to_irq(struct gpio_chip *chip, unsigned int offset)
+{
+ struct sam_gpio *sam = to_sam(chip);
+
+ return irq_create_mapping(sam->domain, offset);
+}
+
+static void sam_irq_mask(struct irq_data *data)
+{
+ struct sam_gpio *sam = irq_data_get_irq_chip_data(data);
+ struct sam_platform_data *pdata = sam->pdata;
+ int bit = sam_gpio_pin_to_irq_bit(sam, data->hwirq);
+
+ if (bit < 0)
+ return;
+
+ if (--sam->irq_group[bit].num_enabled <= 0) {
+ pdata->disable_irq(sam->dev->parent, SAM_IRQ_GPIO, sam->irq,
+ 1 << bit);
+ }
+}
+
+static void sam_irq_unmask(struct irq_data *data)
+{
+ struct sam_gpio *sam = irq_data_get_irq_chip_data(data);
+ struct sam_platform_data *pdata = sam->pdata;
+ int bit = sam_gpio_pin_to_irq_bit(sam, data->hwirq);
+
+ if (bit < 0)
+ return;
+
+ sam->irq_group[bit].num_enabled++;
+ pdata->enable_irq(sam->dev->parent, SAM_IRQ_GPIO, sam->irq, 1 << bit);
+}
+
+static int sam_irq_set_type(struct irq_data *data, unsigned int type)
+{
+ struct sam_gpio *sam = irq_data_get_irq_chip_data(data);
+ int bit = sam_gpio_pin_to_irq_bit(sam, data->hwirq);
+
+ if (bit < 0)
+ return bit;
+
+ sam->irq_type[data->hwirq] = type & 0x0f;
+ sam_gpio_bitop(sam, data->hwirq, SAM_GPIO_OUT_TS, true);
+ sam_gpio_bitop(sam, data->hwirq, SAM_GPIO_DEBOUNCE_EN, type & 0x10);
+ sam_gpio_bitop(sam, data->hwirq,
+ SAM_GPIO_POS_EDGE_EN | SAM_GPIO_POS_EDGE,
+ type & (IRQ_TYPE_EDGE_RISING | IRQ_TYPE_LEVEL_HIGH));
+ sam_gpio_bitop(sam, data->hwirq,
+ SAM_GPIO_NEG_EDGE_EN | SAM_GPIO_NEG_EDGE,
+ type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_LEVEL_LOW));
+
+ return 0;
+}
+
+static void sam_irq_bus_lock(struct irq_data *data)
+{
+ struct sam_gpio *sam = irq_data_get_irq_chip_data(data);
+
+ mutex_lock(&sam->irq_lock);
+}
+
+static void sam_irq_bus_unlock(struct irq_data *data)
+{
+ struct sam_gpio *sam = irq_data_get_irq_chip_data(data);
+
+ /* Synchronize interrupts to chip */
+
+ mutex_unlock(&sam->irq_lock);
+}
+
+static struct irq_chip sam_irq_chip = {
+ .name = "gpio-sam",
+ .irq_mask = sam_irq_mask,
+ .irq_unmask = sam_irq_unmask,
+ .irq_set_type = sam_irq_set_type,
+ .irq_bus_lock = sam_irq_bus_lock,
+ .irq_bus_sync_unlock = sam_irq_bus_unlock,
+};
+
+static int sam_gpio_irq_map(struct irq_domain *domain, unsigned int irq,
+ irq_hw_number_t hwirq)
+{
+ irq_set_chip_data(irq, domain->host_data);
+ irq_set_chip(irq, &sam_irq_chip);
+ irq_set_nested_thread(irq, true);
+
+ irq_set_noprobe(irq);
+
+ return 0;
+}
+
+static const struct irq_domain_ops sam_gpio_irq_domain_ops = {
+ .map = sam_gpio_irq_map,
+ .xlate = irq_domain_xlate_twocell,
+};
+
+static int sam_gpio_irq_setup(struct device *dev, struct sam_gpio *sam)
+{
+ int ret;
+
+ sam->domain = irq_domain_add_linear(dev->of_node,
+ sam->gpio_count,
+ &sam_gpio_irq_domain_ops,
+ sam);
+ if (sam->domain == NULL)
+ return -ENOMEM;
+
+ ret = devm_request_threaded_irq(dev, sam->irq, NULL,
+ sam_gpio_irq_handler,
+ IRQF_ONESHOT,
+ dev_name(dev), sam);
+ if (ret)
+ goto out_remove_domain;
+
+ sam->gpio.to_irq = sam_gpio_to_irq;
+
+ if (!try_module_get(dev->parent->driver->owner)) {
+ ret = -EINVAL;
+ goto out_remove_domain;
+ }
+
+ return 0;
+
+out_remove_domain:
+ irq_domain_remove(sam->domain);
+ sam->domain = NULL;
+ return ret;
+}
+
+static void sam_gpio_irq_teardown(struct device *dev, struct sam_gpio *sam)
+{
+ int i, irq;
+ struct sam_platform_data *pdata = sam->pdata;
+
+ pdata->disable_irq(dev->parent, SAM_IRQ_GPIO, sam->irq, 0xffffffff);
+
+ for (i = 0; i < sam->gpio_count; i++) {
+ irq = irq_find_mapping(sam->domain, i);
+ if (irq > 0)
+ irq_dispose_mapping(irq);
+ }
+ irq_domain_remove(sam->domain);
+ module_put(dev->parent->driver->owner);
+}
+
+static int sam_gpio_unexport(struct sam_gpio *sam)
+{
+ int i;
+
+ if (!sam->export_flags)
+ return 0;
+
+ /* un-export all auto-exported pins */
+ for (i = 0; i < sam->gpio_count; i++) {
+ struct gpio_desc *desc = gpio_to_desc(sam->gpio.base + i);
+
+ if (desc == NULL)
+ continue;
+
+ if (sam->export_flags[i] & GPIOF_EXPORT)
+ gpiochip_free_own_desc(desc);
+ }
+ return 0;
+}
+
+static int sam_gpio_export(struct sam_gpio *sam)
+{
+ int i, ret;
+
+ if (!sam->export_flags)
+ return 0;
+
+ /* auto-export pins as requested */
+
+ for (i = 0; i < sam->gpio_count; i++) {
+ u32 flags = sam->export_flags[i];
+ struct gpio_desc *desc;
+
+ /* request and initialize exported pins */
+ if (!(flags & GPIOF_EXPORT))
+ continue;
+
+ desc = gpiochip_request_own_desc(&sam->gpio, i, "sam-export");
+ if (IS_ERR(desc)) {
+ ret = PTR_ERR(desc);
+ goto error;
+ }
+ if (flags & GPIOF_DIR_IN) {
+ ret = gpiod_direction_input(desc);
+ if (ret)
+ goto error;
+ } else {
+ ret = gpiod_direction_output(desc, flags &
+ (GPIOF_OUT_INIT_HIGH |
+ GPIOF_ACTIVE_LOW));
+ if (ret)
+ goto error;
+ }
+ ret = gpiod_export(desc, flags & GPIOF_EXPORT_CHANGEABLE);
+
+ if (ret)
+ goto error;
+ }
+ return 0;
+
+error:
+ sam_gpio_unexport(sam);
+ return ret;
+}
+
+static int sam_gpio_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct sam_gpio *sam;
+ struct resource *res;
+ int ret;
+ struct sam_platform_data *pdata = dev_get_platdata(&pdev->dev);
+
+ sam = devm_kzalloc(dev, sizeof(*sam), GFP_KERNEL);
+ if (sam == NULL)
+ return -ENOMEM;
+
+ sam->dev = dev;
+ sam->pdata = pdata;
+ platform_set_drvdata(pdev, sam);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+
+ sam->irq = platform_get_irq(pdev, 0);
+ sam->irq_high = platform_get_irq(pdev, 1);
+
+ sam->base = devm_ioremap_nocache(dev, res->start, resource_size(res));
+ if (!sam->base)
+ return -ENOMEM;
+
+ mutex_init(&sam->irq_lock);
+
+ ret = sam_gpio_of_init(dev, sam);
+ if (ret)
+ return ret;
+
+ sam_gpio_setup(sam);
+
+ if (pdata && sam->irq >= 0 && of_find_property(dev->of_node,
+ "interrupt-controller", NULL)) {
+ ret = sam_gpio_irq_setup(dev, sam);
+ if (ret < 0)
+ return ret;
+ }
+
+ ret = gpiochip_add(&sam->gpio);
+ if (ret)
+ goto teardown;
+
+ ret = sam_gpio_export(sam);
+ if (ret)
+ goto teardown_remove;
+
+ return 0;
+
+teardown_remove:
+ gpiochip_remove(&sam->gpio);
+
+teardown:
+ if (sam->domain)
+ sam_gpio_irq_teardown(dev, sam);
+ return ret;
+}
+
+static int sam_gpio_remove(struct platform_device *pdev)
+{
+ struct sam_gpio *sam = platform_get_drvdata(pdev);
+ struct device *dev = &pdev->dev;
+
+ dev_info(dev, "remove\n");
+
+ sam_gpio_unexport(sam);
+
+ if (sam->domain)
+ sam_gpio_irq_teardown(dev, sam);
+
+ gpiochip_remove(&sam->gpio);
+
+ return 0;
+}
+
+static const struct of_device_id sam_gpio_ids[] = {
+ { .compatible = "jnx,gpio-sam", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, sam_gpio_ids);
+
+static struct platform_driver sam_gpio_driver = {
+ .driver = {
+ .name = "gpio-sam",
+ .owner = THIS_MODULE,
+ .of_match_table = sam_gpio_ids,
+ },
+ .probe = sam_gpio_probe,
+ .remove = sam_gpio_remove,
+};
+
+module_platform_driver(sam_gpio_driver);
+
+MODULE_DESCRIPTION("SAM FPGA GPIO Driver");
+MODULE_LICENSE("GPL");
--
1.9.1