summaryrefslogtreecommitdiffstats
path: root/drivers/gpio/gpio-brcmstb.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/gpio/gpio-brcmstb.c')
-rw-r--r--drivers/gpio/gpio-brcmstb.c828
1 files changed, 828 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-brcmstb.c b/drivers/gpio/gpio-brcmstb.c
new file mode 100644
index 000000000..fcfc1a1f1
--- /dev/null
+++ b/drivers/gpio/gpio-brcmstb.c
@@ -0,0 +1,828 @@
+/*
+ * Copyright (C) 2015-2017 Broadcom
+ *
+ * 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.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/bitops.h>
+#include <linux/gpio/driver.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/module.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/interrupt.h>
+
+enum gio_reg_index {
+ GIO_REG_ODEN = 0,
+ GIO_REG_DATA,
+ GIO_REG_IODIR,
+ GIO_REG_EC,
+ GIO_REG_EI,
+ GIO_REG_MASK,
+ GIO_REG_LEVEL,
+ GIO_REG_STAT,
+ NUMBER_OF_GIO_REGISTERS
+};
+
+#define GIO_BANK_SIZE (NUMBER_OF_GIO_REGISTERS * sizeof(u32))
+#define GIO_BANK_OFF(bank, off) (((bank) * GIO_BANK_SIZE) + (off * sizeof(u32)))
+#define GIO_ODEN(bank) GIO_BANK_OFF(bank, GIO_REG_ODEN)
+#define GIO_DATA(bank) GIO_BANK_OFF(bank, GIO_REG_DATA)
+#define GIO_IODIR(bank) GIO_BANK_OFF(bank, GIO_REG_IODIR)
+#define GIO_EC(bank) GIO_BANK_OFF(bank, GIO_REG_EC)
+#define GIO_EI(bank) GIO_BANK_OFF(bank, GIO_REG_EI)
+#define GIO_MASK(bank) GIO_BANK_OFF(bank, GIO_REG_MASK)
+#define GIO_LEVEL(bank) GIO_BANK_OFF(bank, GIO_REG_LEVEL)
+#define GIO_STAT(bank) GIO_BANK_OFF(bank, GIO_REG_STAT)
+
+struct brcmstb_gpio_bank {
+ struct list_head node;
+ int id;
+ struct gpio_chip gc;
+ struct brcmstb_gpio_priv *parent_priv;
+ u32 width;
+ u32 wake_active;
+ u32 saved_regs[GIO_REG_STAT]; /* Don't save and restore GIO_REG_STAT */
+};
+
+struct brcmstb_gpio_priv {
+ struct list_head bank_list;
+ void __iomem *reg_base;
+ struct platform_device *pdev;
+ struct irq_domain *irq_domain;
+ struct irq_chip irq_chip;
+ int parent_irq;
+ int gpio_base;
+ int num_gpios;
+ int parent_wake_irq;
+};
+
+#define MAX_GPIO_PER_BANK 32
+#define GPIO_BANK(gpio) ((gpio) >> 5)
+/* assumes MAX_GPIO_PER_BANK is a multiple of 2 */
+#define GPIO_BIT(gpio) ((gpio) & (MAX_GPIO_PER_BANK - 1))
+
+static inline struct brcmstb_gpio_priv *
+brcmstb_gpio_gc_to_priv(struct gpio_chip *gc)
+{
+ struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
+ return bank->parent_priv;
+}
+
+static unsigned long
+__brcmstb_gpio_get_active_irqs(struct brcmstb_gpio_bank *bank)
+{
+ void __iomem *reg_base = bank->parent_priv->reg_base;
+
+ return bank->gc.read_reg(reg_base + GIO_STAT(bank->id)) &
+ bank->gc.read_reg(reg_base + GIO_MASK(bank->id));
+}
+
+static unsigned long
+brcmstb_gpio_get_active_irqs(struct brcmstb_gpio_bank *bank)
+{
+ unsigned long status;
+ unsigned long flags;
+
+ spin_lock_irqsave(&bank->gc.bgpio_lock, flags);
+ status = __brcmstb_gpio_get_active_irqs(bank);
+ spin_unlock_irqrestore(&bank->gc.bgpio_lock, flags);
+
+ return status;
+}
+
+static int brcmstb_gpio_hwirq_to_offset(irq_hw_number_t hwirq,
+ struct brcmstb_gpio_bank *bank)
+{
+ return hwirq - (bank->gc.base - bank->parent_priv->gpio_base);
+}
+
+static void brcmstb_gpio_set_imask(struct brcmstb_gpio_bank *bank,
+ unsigned int hwirq, bool enable)
+{
+ struct gpio_chip *gc = &bank->gc;
+ struct brcmstb_gpio_priv *priv = bank->parent_priv;
+ u32 mask = BIT(brcmstb_gpio_hwirq_to_offset(hwirq, bank));
+ u32 imask;
+ unsigned long flags;
+
+ spin_lock_irqsave(&gc->bgpio_lock, flags);
+ imask = gc->read_reg(priv->reg_base + GIO_MASK(bank->id));
+ if (enable)
+ imask |= mask;
+ else
+ imask &= ~mask;
+ gc->write_reg(priv->reg_base + GIO_MASK(bank->id), imask);
+ spin_unlock_irqrestore(&gc->bgpio_lock, flags);
+}
+
+static int brcmstb_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
+{
+ struct brcmstb_gpio_priv *priv = brcmstb_gpio_gc_to_priv(gc);
+ /* gc_offset is relative to this gpio_chip; want real offset */
+ int hwirq = offset + (gc->base - priv->gpio_base);
+
+ if (hwirq >= priv->num_gpios)
+ return -ENXIO;
+ return irq_create_mapping(priv->irq_domain, hwirq);
+}
+
+/* -------------------- IRQ chip functions -------------------- */
+
+static void brcmstb_gpio_irq_mask(struct irq_data *d)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
+
+ brcmstb_gpio_set_imask(bank, d->hwirq, false);
+}
+
+static void brcmstb_gpio_irq_unmask(struct irq_data *d)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
+
+ brcmstb_gpio_set_imask(bank, d->hwirq, true);
+}
+
+static void brcmstb_gpio_irq_ack(struct irq_data *d)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
+ struct brcmstb_gpio_priv *priv = bank->parent_priv;
+ u32 mask = BIT(brcmstb_gpio_hwirq_to_offset(d->hwirq, bank));
+
+ gc->write_reg(priv->reg_base + GIO_STAT(bank->id), mask);
+}
+
+static int brcmstb_gpio_irq_set_type(struct irq_data *d, unsigned int type)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
+ struct brcmstb_gpio_priv *priv = bank->parent_priv;
+ u32 mask = BIT(brcmstb_gpio_hwirq_to_offset(d->hwirq, bank));
+ u32 edge_insensitive, iedge_insensitive;
+ u32 edge_config, iedge_config;
+ u32 level, ilevel;
+ unsigned long flags;
+
+ switch (type) {
+ case IRQ_TYPE_LEVEL_LOW:
+ level = mask;
+ edge_config = 0;
+ edge_insensitive = 0;
+ break;
+ case IRQ_TYPE_LEVEL_HIGH:
+ level = mask;
+ edge_config = mask;
+ edge_insensitive = 0;
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ level = 0;
+ edge_config = 0;
+ edge_insensitive = 0;
+ break;
+ case IRQ_TYPE_EDGE_RISING:
+ level = 0;
+ edge_config = mask;
+ edge_insensitive = 0;
+ break;
+ case IRQ_TYPE_EDGE_BOTH:
+ level = 0;
+ edge_config = 0; /* don't care, but want known value */
+ edge_insensitive = mask;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ spin_lock_irqsave(&bank->gc.bgpio_lock, flags);
+
+ iedge_config = bank->gc.read_reg(priv->reg_base +
+ GIO_EC(bank->id)) & ~mask;
+ iedge_insensitive = bank->gc.read_reg(priv->reg_base +
+ GIO_EI(bank->id)) & ~mask;
+ ilevel = bank->gc.read_reg(priv->reg_base +
+ GIO_LEVEL(bank->id)) & ~mask;
+
+ bank->gc.write_reg(priv->reg_base + GIO_EC(bank->id),
+ iedge_config | edge_config);
+ bank->gc.write_reg(priv->reg_base + GIO_EI(bank->id),
+ iedge_insensitive | edge_insensitive);
+ bank->gc.write_reg(priv->reg_base + GIO_LEVEL(bank->id),
+ ilevel | level);
+
+ spin_unlock_irqrestore(&bank->gc.bgpio_lock, flags);
+ return 0;
+}
+
+static int brcmstb_gpio_priv_set_wake(struct brcmstb_gpio_priv *priv,
+ unsigned int enable)
+{
+ int ret = 0;
+
+ if (enable)
+ ret = enable_irq_wake(priv->parent_wake_irq);
+ else
+ ret = disable_irq_wake(priv->parent_wake_irq);
+ if (ret)
+ dev_err(&priv->pdev->dev, "failed to %s wake-up interrupt\n",
+ enable ? "enable" : "disable");
+ return ret;
+}
+
+static int brcmstb_gpio_irq_set_wake(struct irq_data *d, unsigned int enable)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
+ struct brcmstb_gpio_priv *priv = bank->parent_priv;
+ u32 mask = BIT(brcmstb_gpio_hwirq_to_offset(d->hwirq, bank));
+
+ /*
+ * Do not do anything specific for now, suspend/resume callbacks will
+ * configure the interrupt mask appropriately
+ */
+ if (enable)
+ bank->wake_active |= mask;
+ else
+ bank->wake_active &= ~mask;
+
+ return brcmstb_gpio_priv_set_wake(priv, enable);
+}
+
+static irqreturn_t brcmstb_gpio_wake_irq_handler(int irq, void *data)
+{
+ struct brcmstb_gpio_priv *priv = data;
+
+ if (!priv || irq != priv->parent_wake_irq)
+ return IRQ_NONE;
+
+ /* Nothing to do */
+ return IRQ_HANDLED;
+}
+
+static void brcmstb_gpio_irq_bank_handler(struct brcmstb_gpio_bank *bank)
+{
+ struct brcmstb_gpio_priv *priv = bank->parent_priv;
+ struct irq_domain *domain = priv->irq_domain;
+ int hwbase = bank->gc.base - priv->gpio_base;
+ unsigned long status;
+
+ while ((status = brcmstb_gpio_get_active_irqs(bank))) {
+ unsigned int irq, offset;
+
+ for_each_set_bit(offset, &status, 32) {
+ if (offset >= bank->width)
+ dev_warn(&priv->pdev->dev,
+ "IRQ for invalid GPIO (bank=%d, offset=%d)\n",
+ bank->id, offset);
+ irq = irq_linear_revmap(domain, hwbase + offset);
+ generic_handle_irq(irq);
+ }
+ }
+}
+
+/* Each UPG GIO block has one IRQ for all banks */
+static void brcmstb_gpio_irq_handler(struct irq_desc *desc)
+{
+ struct brcmstb_gpio_priv *priv = irq_desc_get_handler_data(desc);
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ struct brcmstb_gpio_bank *bank;
+
+ /* Interrupts weren't properly cleared during probe */
+ BUG_ON(!priv || !chip);
+
+ chained_irq_enter(chip, desc);
+ list_for_each_entry(bank, &priv->bank_list, node)
+ brcmstb_gpio_irq_bank_handler(bank);
+ chained_irq_exit(chip, desc);
+}
+
+static struct brcmstb_gpio_bank *brcmstb_gpio_hwirq_to_bank(
+ struct brcmstb_gpio_priv *priv, irq_hw_number_t hwirq)
+{
+ struct brcmstb_gpio_bank *bank;
+ int i = 0;
+
+ /* banks are in descending order */
+ list_for_each_entry_reverse(bank, &priv->bank_list, node) {
+ i += bank->gc.ngpio;
+ if (hwirq < i)
+ return bank;
+ }
+ return NULL;
+}
+
+/*
+ * This lock class tells lockdep that GPIO irqs are in a different
+ * category than their parents, so it won't report false recursion.
+ */
+static struct lock_class_key brcmstb_gpio_irq_lock_class;
+static struct lock_class_key brcmstb_gpio_irq_request_class;
+
+
+static int brcmstb_gpio_irq_map(struct irq_domain *d, unsigned int irq,
+ irq_hw_number_t hwirq)
+{
+ struct brcmstb_gpio_priv *priv = d->host_data;
+ struct brcmstb_gpio_bank *bank =
+ brcmstb_gpio_hwirq_to_bank(priv, hwirq);
+ struct platform_device *pdev = priv->pdev;
+ int ret;
+
+ if (!bank)
+ return -EINVAL;
+
+ dev_dbg(&pdev->dev, "Mapping irq %d for gpio line %d (bank %d)\n",
+ irq, (int)hwirq, bank->id);
+ ret = irq_set_chip_data(irq, &bank->gc);
+ if (ret < 0)
+ return ret;
+ irq_set_lockdep_class(irq, &brcmstb_gpio_irq_lock_class,
+ &brcmstb_gpio_irq_request_class);
+ irq_set_chip_and_handler(irq, &priv->irq_chip, handle_level_irq);
+ irq_set_noprobe(irq);
+ return 0;
+}
+
+static void brcmstb_gpio_irq_unmap(struct irq_domain *d, unsigned int irq)
+{
+ irq_set_chip_and_handler(irq, NULL, NULL);
+ irq_set_chip_data(irq, NULL);
+}
+
+static const struct irq_domain_ops brcmstb_gpio_irq_domain_ops = {
+ .map = brcmstb_gpio_irq_map,
+ .unmap = brcmstb_gpio_irq_unmap,
+ .xlate = irq_domain_xlate_twocell,
+};
+
+/* Make sure that the number of banks matches up between properties */
+static int brcmstb_gpio_sanity_check_banks(struct device *dev,
+ struct device_node *np, struct resource *res)
+{
+ int res_num_banks = resource_size(res) / GIO_BANK_SIZE;
+ int num_banks =
+ of_property_count_u32_elems(np, "brcm,gpio-bank-widths");
+
+ if (res_num_banks != num_banks) {
+ dev_err(dev, "Mismatch in banks: res had %d, bank-widths had %d\n",
+ res_num_banks, num_banks);
+ return -EINVAL;
+ } else {
+ return 0;
+ }
+}
+
+static int brcmstb_gpio_remove(struct platform_device *pdev)
+{
+ struct brcmstb_gpio_priv *priv = platform_get_drvdata(pdev);
+ struct brcmstb_gpio_bank *bank;
+ int offset, ret = 0, virq;
+
+ if (!priv) {
+ dev_err(&pdev->dev, "called %s without drvdata!\n", __func__);
+ return -EFAULT;
+ }
+
+ if (priv->parent_irq > 0)
+ irq_set_chained_handler_and_data(priv->parent_irq, NULL, NULL);
+
+ /* Remove all IRQ mappings and delete the domain */
+ if (priv->irq_domain) {
+ for (offset = 0; offset < priv->num_gpios; offset++) {
+ virq = irq_find_mapping(priv->irq_domain, offset);
+ irq_dispose_mapping(virq);
+ }
+ irq_domain_remove(priv->irq_domain);
+ }
+
+ /*
+ * You can lose return values below, but we report all errors, and it's
+ * more important to actually perform all of the steps.
+ */
+ list_for_each_entry(bank, &priv->bank_list, node)
+ gpiochip_remove(&bank->gc);
+
+ return ret;
+}
+
+static int brcmstb_gpio_of_xlate(struct gpio_chip *gc,
+ const struct of_phandle_args *gpiospec, u32 *flags)
+{
+ struct brcmstb_gpio_priv *priv = brcmstb_gpio_gc_to_priv(gc);
+ struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
+ int offset;
+
+ if (gc->of_gpio_n_cells != 2) {
+ WARN_ON(1);
+ return -EINVAL;
+ }
+
+ if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
+ return -EINVAL;
+
+ offset = gpiospec->args[0] - (gc->base - priv->gpio_base);
+ if (offset >= gc->ngpio || offset < 0)
+ return -EINVAL;
+
+ if (unlikely(offset >= bank->width)) {
+ dev_warn_ratelimited(&priv->pdev->dev,
+ "Received request for invalid GPIO offset %d\n",
+ gpiospec->args[0]);
+ }
+
+ if (flags)
+ *flags = gpiospec->args[1];
+
+ return offset;
+}
+
+/* priv->parent_irq and priv->num_gpios must be set before calling */
+static int brcmstb_gpio_irq_setup(struct platform_device *pdev,
+ struct brcmstb_gpio_priv *priv)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ int err;
+
+ priv->irq_domain =
+ irq_domain_add_linear(np, priv->num_gpios,
+ &brcmstb_gpio_irq_domain_ops,
+ priv);
+ if (!priv->irq_domain) {
+ dev_err(dev, "Couldn't allocate IRQ domain\n");
+ return -ENXIO;
+ }
+
+ if (of_property_read_bool(np, "wakeup-source")) {
+ priv->parent_wake_irq = platform_get_irq(pdev, 1);
+ if (priv->parent_wake_irq < 0) {
+ priv->parent_wake_irq = 0;
+ dev_warn(dev,
+ "Couldn't get wake IRQ - GPIOs will not be able to wake from sleep");
+ } else {
+ /*
+ * Set wakeup capability so we can process boot-time
+ * "wakeups" (e.g., from S5 cold boot)
+ */
+ device_set_wakeup_capable(dev, true);
+ device_wakeup_enable(dev);
+ err = devm_request_irq(dev, priv->parent_wake_irq,
+ brcmstb_gpio_wake_irq_handler,
+ IRQF_SHARED,
+ "brcmstb-gpio-wake", priv);
+
+ if (err < 0) {
+ dev_err(dev, "Couldn't request wake IRQ");
+ goto out_free_domain;
+ }
+ }
+ }
+
+ priv->irq_chip.name = dev_name(dev);
+ priv->irq_chip.irq_disable = brcmstb_gpio_irq_mask;
+ priv->irq_chip.irq_mask = brcmstb_gpio_irq_mask;
+ priv->irq_chip.irq_unmask = brcmstb_gpio_irq_unmask;
+ priv->irq_chip.irq_ack = brcmstb_gpio_irq_ack;
+ priv->irq_chip.irq_set_type = brcmstb_gpio_irq_set_type;
+
+ if (priv->parent_wake_irq)
+ priv->irq_chip.irq_set_wake = brcmstb_gpio_irq_set_wake;
+
+ irq_set_chained_handler_and_data(priv->parent_irq,
+ brcmstb_gpio_irq_handler, priv);
+ irq_set_status_flags(priv->parent_irq, IRQ_DISABLE_UNLAZY);
+
+ return 0;
+
+out_free_domain:
+ irq_domain_remove(priv->irq_domain);
+
+ return err;
+}
+
+static void brcmstb_gpio_bank_save(struct brcmstb_gpio_priv *priv,
+ struct brcmstb_gpio_bank *bank)
+{
+ struct gpio_chip *gc = &bank->gc;
+ unsigned int i;
+
+ for (i = 0; i < GIO_REG_STAT; i++)
+ bank->saved_regs[i] = gc->read_reg(priv->reg_base +
+ GIO_BANK_OFF(bank->id, i));
+}
+
+static void brcmstb_gpio_quiesce(struct device *dev, bool save)
+{
+ struct brcmstb_gpio_priv *priv = dev_get_drvdata(dev);
+ struct brcmstb_gpio_bank *bank;
+ struct gpio_chip *gc;
+ u32 imask;
+
+ /* disable non-wake interrupt */
+ if (priv->parent_irq >= 0)
+ disable_irq(priv->parent_irq);
+
+ list_for_each_entry(bank, &priv->bank_list, node) {
+ gc = &bank->gc;
+
+ if (save)
+ brcmstb_gpio_bank_save(priv, bank);
+
+ /* Unmask GPIOs which have been flagged as wake-up sources */
+ if (priv->parent_wake_irq)
+ imask = bank->wake_active;
+ else
+ imask = 0;
+ gc->write_reg(priv->reg_base + GIO_MASK(bank->id),
+ imask);
+ }
+}
+
+static void brcmstb_gpio_shutdown(struct platform_device *pdev)
+{
+ /* Enable GPIO for S5 cold boot */
+ brcmstb_gpio_quiesce(&pdev->dev, false);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static void brcmstb_gpio_bank_restore(struct brcmstb_gpio_priv *priv,
+ struct brcmstb_gpio_bank *bank)
+{
+ struct gpio_chip *gc = &bank->gc;
+ unsigned int i;
+
+ for (i = 0; i < GIO_REG_STAT; i++)
+ gc->write_reg(priv->reg_base + GIO_BANK_OFF(bank->id, i),
+ bank->saved_regs[i]);
+}
+
+static int brcmstb_gpio_suspend(struct device *dev)
+{
+ brcmstb_gpio_quiesce(dev, true);
+ return 0;
+}
+
+static int brcmstb_gpio_resume(struct device *dev)
+{
+ struct brcmstb_gpio_priv *priv = dev_get_drvdata(dev);
+ struct brcmstb_gpio_bank *bank;
+ bool need_wakeup_event = false;
+
+ list_for_each_entry(bank, &priv->bank_list, node) {
+ need_wakeup_event |= !!__brcmstb_gpio_get_active_irqs(bank);
+ brcmstb_gpio_bank_restore(priv, bank);
+ }
+
+ if (priv->parent_wake_irq && need_wakeup_event)
+ pm_wakeup_event(dev, 0);
+
+ /* enable non-wake interrupt */
+ if (priv->parent_irq >= 0)
+ enable_irq(priv->parent_irq);
+
+ return 0;
+}
+
+#else
+#define brcmstb_gpio_suspend NULL
+#define brcmstb_gpio_resume NULL
+#endif /* CONFIG_PM_SLEEP */
+
+static const struct dev_pm_ops brcmstb_gpio_pm_ops = {
+ .suspend_noirq = brcmstb_gpio_suspend,
+ .resume_noirq = brcmstb_gpio_resume,
+};
+
+static void brcmstb_gpio_set_names(struct device *dev,
+ struct brcmstb_gpio_bank *bank)
+{
+ struct device_node *np = dev->of_node;
+ const char **names;
+ int nstrings, base;
+ unsigned int i;
+
+ base = bank->id * MAX_GPIO_PER_BANK;
+
+ nstrings = of_property_count_strings(np, "gpio-line-names");
+ if (nstrings <= base)
+ /* Line names not present */
+ return;
+
+ names = devm_kcalloc(dev, MAX_GPIO_PER_BANK, sizeof(*names),
+ GFP_KERNEL);
+ if (!names)
+ return;
+
+ /*
+ * Make sure to not index beyond the end of the number of descriptors
+ * of the GPIO device.
+ */
+ for (i = 0; i < bank->width; i++) {
+ const char *name;
+ int ret;
+
+ ret = of_property_read_string_index(np, "gpio-line-names",
+ base + i, &name);
+ if (ret) {
+ if (ret != -ENODATA)
+ dev_err(dev, "unable to name line %d: %d\n",
+ base + i, ret);
+ break;
+ }
+ if (*name)
+ names[i] = name;
+ }
+
+ bank->gc.names = names;
+}
+
+static int brcmstb_gpio_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ void __iomem *reg_base;
+ struct brcmstb_gpio_priv *priv;
+ struct resource *res;
+ struct property *prop;
+ const __be32 *p;
+ u32 bank_width;
+ int num_banks = 0;
+ int err;
+ static int gpio_base;
+ unsigned long flags = 0;
+ bool need_wakeup_event = false;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+ platform_set_drvdata(pdev, priv);
+ INIT_LIST_HEAD(&priv->bank_list);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ reg_base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(reg_base))
+ return PTR_ERR(reg_base);
+
+ priv->gpio_base = gpio_base;
+ priv->reg_base = reg_base;
+ priv->pdev = pdev;
+
+ if (of_property_read_bool(np, "interrupt-controller")) {
+ priv->parent_irq = platform_get_irq(pdev, 0);
+ if (priv->parent_irq <= 0)
+ return -ENOENT;
+ } else {
+ priv->parent_irq = -ENOENT;
+ }
+
+ if (brcmstb_gpio_sanity_check_banks(dev, np, res))
+ return -EINVAL;
+
+ /*
+ * MIPS endianness is configured by boot strap, which also reverses all
+ * bus endianness (i.e., big-endian CPU + big endian bus ==> native
+ * endian I/O).
+ *
+ * Other architectures (e.g., ARM) either do not support big endian, or
+ * else leave I/O in little endian mode.
+ */
+#if defined(CONFIG_MIPS) && defined(__BIG_ENDIAN)
+ flags = BGPIOF_BIG_ENDIAN_BYTE_ORDER;
+#endif
+
+ of_property_for_each_u32(np, "brcm,gpio-bank-widths", prop, p,
+ bank_width) {
+ struct brcmstb_gpio_bank *bank;
+ struct gpio_chip *gc;
+
+ /*
+ * If bank_width is 0, then there is an empty bank in the
+ * register block. Special handling for this case.
+ */
+ if (bank_width == 0) {
+ dev_dbg(dev, "Width 0 found: Empty bank @ %d\n",
+ num_banks);
+ num_banks++;
+ gpio_base += MAX_GPIO_PER_BANK;
+ continue;
+ }
+
+ bank = devm_kzalloc(dev, sizeof(*bank), GFP_KERNEL);
+ if (!bank) {
+ err = -ENOMEM;
+ goto fail;
+ }
+
+ bank->parent_priv = priv;
+ bank->id = num_banks;
+ if (bank_width <= 0 || bank_width > MAX_GPIO_PER_BANK) {
+ dev_err(dev, "Invalid bank width %d\n", bank_width);
+ err = -EINVAL;
+ goto fail;
+ } else {
+ bank->width = bank_width;
+ }
+
+ /*
+ * Regs are 4 bytes wide, have data reg, no set/clear regs,
+ * and direction bits have 0 = output and 1 = input
+ */
+ gc = &bank->gc;
+ err = bgpio_init(gc, dev, 4,
+ reg_base + GIO_DATA(bank->id),
+ NULL, NULL, NULL,
+ reg_base + GIO_IODIR(bank->id), flags);
+ if (err) {
+ dev_err(dev, "bgpio_init() failed\n");
+ goto fail;
+ }
+
+ gc->of_node = np;
+ gc->owner = THIS_MODULE;
+ gc->label = devm_kasprintf(dev, GFP_KERNEL, "%pOF", dev->of_node);
+ if (!gc->label) {
+ err = -ENOMEM;
+ goto fail;
+ }
+ gc->base = gpio_base;
+ gc->of_gpio_n_cells = 2;
+ gc->of_xlate = brcmstb_gpio_of_xlate;
+ /* not all ngpio lines are valid, will use bank width later */
+ gc->ngpio = MAX_GPIO_PER_BANK;
+ if (priv->parent_irq > 0)
+ gc->to_irq = brcmstb_gpio_to_irq;
+
+ /*
+ * Mask all interrupts by default, since wakeup interrupts may
+ * be retained from S5 cold boot
+ */
+ need_wakeup_event |= !!__brcmstb_gpio_get_active_irqs(bank);
+ gc->write_reg(reg_base + GIO_MASK(bank->id), 0);
+
+ brcmstb_gpio_set_names(dev, bank);
+ err = gpiochip_add_data(gc, bank);
+ if (err) {
+ dev_err(dev, "Could not add gpiochip for bank %d\n",
+ bank->id);
+ goto fail;
+ }
+ gpio_base += gc->ngpio;
+
+ dev_dbg(dev, "bank=%d, base=%d, ngpio=%d, width=%d\n", bank->id,
+ gc->base, gc->ngpio, bank->width);
+
+ /* Everything looks good, so add bank to list */
+ list_add(&bank->node, &priv->bank_list);
+
+ num_banks++;
+ }
+
+ priv->num_gpios = gpio_base - priv->gpio_base;
+ if (priv->parent_irq > 0) {
+ err = brcmstb_gpio_irq_setup(pdev, priv);
+ if (err)
+ goto fail;
+ }
+
+ if (priv->parent_wake_irq && need_wakeup_event)
+ pm_wakeup_event(dev, 0);
+
+ return 0;
+
+fail:
+ (void) brcmstb_gpio_remove(pdev);
+ return err;
+}
+
+static const struct of_device_id brcmstb_gpio_of_match[] = {
+ { .compatible = "brcm,brcmstb-gpio" },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, brcmstb_gpio_of_match);
+
+static struct platform_driver brcmstb_gpio_driver = {
+ .driver = {
+ .name = "brcmstb-gpio",
+ .of_match_table = brcmstb_gpio_of_match,
+ .pm = &brcmstb_gpio_pm_ops,
+ },
+ .probe = brcmstb_gpio_probe,
+ .remove = brcmstb_gpio_remove,
+ .shutdown = brcmstb_gpio_shutdown,
+};
+module_platform_driver(brcmstb_gpio_driver);
+
+MODULE_AUTHOR("Gregory Fong");
+MODULE_DESCRIPTION("Driver for Broadcom BRCMSTB SoC UPG GPIO");
+MODULE_LICENSE("GPL v2");