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path: root/drivers/base/regmap/regmap-irq.c
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Diffstat (limited to 'drivers/base/regmap/regmap-irq.c')
-rw-r--r--drivers/base/regmap/regmap-irq.c599
1 files changed, 599 insertions, 0 deletions
diff --git a/drivers/base/regmap/regmap-irq.c b/drivers/base/regmap/regmap-irq.c
new file mode 100644
index 000000000..a6c3f75b4
--- /dev/null
+++ b/drivers/base/regmap/regmap-irq.c
@@ -0,0 +1,599 @@
+/*
+ * regmap based irq_chip
+ *
+ * Copyright 2011 Wolfson Microelectronics plc
+ *
+ * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#include "internal.h"
+
+struct regmap_irq_chip_data {
+ struct mutex lock;
+ struct irq_chip irq_chip;
+
+ struct regmap *map;
+ const struct regmap_irq_chip *chip;
+
+ int irq_base;
+ struct irq_domain *domain;
+
+ int irq;
+ int wake_count;
+
+ void *status_reg_buf;
+ unsigned int *status_buf;
+ unsigned int *mask_buf;
+ unsigned int *mask_buf_def;
+ unsigned int *wake_buf;
+
+ unsigned int irq_reg_stride;
+};
+
+static inline const
+struct regmap_irq *irq_to_regmap_irq(struct regmap_irq_chip_data *data,
+ int irq)
+{
+ return &data->chip->irqs[irq];
+}
+
+static void regmap_irq_lock(struct irq_data *data)
+{
+ struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);
+
+ mutex_lock(&d->lock);
+}
+
+static void regmap_irq_sync_unlock(struct irq_data *data)
+{
+ struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);
+ struct regmap *map = d->map;
+ int i, ret;
+ u32 reg;
+
+ if (d->chip->runtime_pm) {
+ ret = pm_runtime_get_sync(map->dev);
+ if (ret < 0)
+ dev_err(map->dev, "IRQ sync failed to resume: %d\n",
+ ret);
+ }
+
+ /*
+ * If there's been a change in the mask write it back to the
+ * hardware. We rely on the use of the regmap core cache to
+ * suppress pointless writes.
+ */
+ for (i = 0; i < d->chip->num_regs; i++) {
+ reg = d->chip->mask_base +
+ (i * map->reg_stride * d->irq_reg_stride);
+ if (d->chip->mask_invert)
+ ret = regmap_update_bits(d->map, reg,
+ d->mask_buf_def[i], ~d->mask_buf[i]);
+ else
+ ret = regmap_update_bits(d->map, reg,
+ d->mask_buf_def[i], d->mask_buf[i]);
+ if (ret != 0)
+ dev_err(d->map->dev, "Failed to sync masks in %x\n",
+ reg);
+
+ reg = d->chip->wake_base +
+ (i * map->reg_stride * d->irq_reg_stride);
+ if (d->wake_buf) {
+ if (d->chip->wake_invert)
+ ret = regmap_update_bits(d->map, reg,
+ d->mask_buf_def[i],
+ ~d->wake_buf[i]);
+ else
+ ret = regmap_update_bits(d->map, reg,
+ d->mask_buf_def[i],
+ d->wake_buf[i]);
+ if (ret != 0)
+ dev_err(d->map->dev,
+ "Failed to sync wakes in %x: %d\n",
+ reg, ret);
+ }
+
+ if (!d->chip->init_ack_masked)
+ continue;
+ /*
+ * Ack all the masked interrupts uncondictionly,
+ * OR if there is masked interrupt which hasn't been Acked,
+ * it'll be ignored in irq handler, then may introduce irq storm
+ */
+ if (d->mask_buf[i] && (d->chip->ack_base || d->chip->use_ack)) {
+ reg = d->chip->ack_base +
+ (i * map->reg_stride * d->irq_reg_stride);
+ ret = regmap_write(map, reg, d->mask_buf[i]);
+ if (ret != 0)
+ dev_err(d->map->dev, "Failed to ack 0x%x: %d\n",
+ reg, ret);
+ }
+ }
+
+ if (d->chip->runtime_pm)
+ pm_runtime_put(map->dev);
+
+ /* If we've changed our wakeup count propagate it to the parent */
+ if (d->wake_count < 0)
+ for (i = d->wake_count; i < 0; i++)
+ irq_set_irq_wake(d->irq, 0);
+ else if (d->wake_count > 0)
+ for (i = 0; i < d->wake_count; i++)
+ irq_set_irq_wake(d->irq, 1);
+
+ d->wake_count = 0;
+
+ mutex_unlock(&d->lock);
+}
+
+static void regmap_irq_enable(struct irq_data *data)
+{
+ struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);
+ struct regmap *map = d->map;
+ const struct regmap_irq *irq_data = irq_to_regmap_irq(d, data->hwirq);
+
+ d->mask_buf[irq_data->reg_offset / map->reg_stride] &= ~irq_data->mask;
+}
+
+static void regmap_irq_disable(struct irq_data *data)
+{
+ struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);
+ struct regmap *map = d->map;
+ const struct regmap_irq *irq_data = irq_to_regmap_irq(d, data->hwirq);
+
+ d->mask_buf[irq_data->reg_offset / map->reg_stride] |= irq_data->mask;
+}
+
+static int regmap_irq_set_wake(struct irq_data *data, unsigned int on)
+{
+ struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);
+ struct regmap *map = d->map;
+ const struct regmap_irq *irq_data = irq_to_regmap_irq(d, data->hwirq);
+
+ if (on) {
+ if (d->wake_buf)
+ d->wake_buf[irq_data->reg_offset / map->reg_stride]
+ &= ~irq_data->mask;
+ d->wake_count++;
+ } else {
+ if (d->wake_buf)
+ d->wake_buf[irq_data->reg_offset / map->reg_stride]
+ |= irq_data->mask;
+ d->wake_count--;
+ }
+
+ return 0;
+}
+
+static const struct irq_chip regmap_irq_chip = {
+ .irq_bus_lock = regmap_irq_lock,
+ .irq_bus_sync_unlock = regmap_irq_sync_unlock,
+ .irq_disable = regmap_irq_disable,
+ .irq_enable = regmap_irq_enable,
+ .irq_set_wake = regmap_irq_set_wake,
+};
+
+static irqreturn_t regmap_irq_thread(int irq, void *d)
+{
+ struct regmap_irq_chip_data *data = d;
+ const struct regmap_irq_chip *chip = data->chip;
+ struct regmap *map = data->map;
+ int ret, i;
+ bool handled = false;
+ u32 reg;
+
+ if (chip->runtime_pm) {
+ ret = pm_runtime_get_sync(map->dev);
+ if (ret < 0) {
+ dev_err(map->dev, "IRQ thread failed to resume: %d\n",
+ ret);
+ pm_runtime_put(map->dev);
+ return IRQ_NONE;
+ }
+ }
+
+ /*
+ * Read in the statuses, using a single bulk read if possible
+ * in order to reduce the I/O overheads.
+ */
+ if (!map->use_single_rw && map->reg_stride == 1 &&
+ data->irq_reg_stride == 1) {
+ u8 *buf8 = data->status_reg_buf;
+ u16 *buf16 = data->status_reg_buf;
+ u32 *buf32 = data->status_reg_buf;
+
+ BUG_ON(!data->status_reg_buf);
+
+ ret = regmap_bulk_read(map, chip->status_base,
+ data->status_reg_buf,
+ chip->num_regs);
+ if (ret != 0) {
+ dev_err(map->dev, "Failed to read IRQ status: %d\n",
+ ret);
+ return IRQ_NONE;
+ }
+
+ for (i = 0; i < data->chip->num_regs; i++) {
+ switch (map->format.val_bytes) {
+ case 1:
+ data->status_buf[i] = buf8[i];
+ break;
+ case 2:
+ data->status_buf[i] = buf16[i];
+ break;
+ case 4:
+ data->status_buf[i] = buf32[i];
+ break;
+ default:
+ BUG();
+ return IRQ_NONE;
+ }
+ }
+
+ } else {
+ for (i = 0; i < data->chip->num_regs; i++) {
+ ret = regmap_read(map, chip->status_base +
+ (i * map->reg_stride
+ * data->irq_reg_stride),
+ &data->status_buf[i]);
+
+ if (ret != 0) {
+ dev_err(map->dev,
+ "Failed to read IRQ status: %d\n",
+ ret);
+ if (chip->runtime_pm)
+ pm_runtime_put(map->dev);
+ return IRQ_NONE;
+ }
+ }
+ }
+
+ /*
+ * Ignore masked IRQs and ack if we need to; we ack early so
+ * there is no race between handling and acknowleding the
+ * interrupt. We assume that typically few of the interrupts
+ * will fire simultaneously so don't worry about overhead from
+ * doing a write per register.
+ */
+ for (i = 0; i < data->chip->num_regs; i++) {
+ data->status_buf[i] &= ~data->mask_buf[i];
+
+ if (data->status_buf[i] && (chip->ack_base || chip->use_ack)) {
+ reg = chip->ack_base +
+ (i * map->reg_stride * data->irq_reg_stride);
+ ret = regmap_write(map, reg, data->status_buf[i]);
+ if (ret != 0)
+ dev_err(map->dev, "Failed to ack 0x%x: %d\n",
+ reg, ret);
+ }
+ }
+
+ for (i = 0; i < chip->num_irqs; i++) {
+ if (data->status_buf[chip->irqs[i].reg_offset /
+ map->reg_stride] & chip->irqs[i].mask) {
+ handle_nested_irq(irq_find_mapping(data->domain, i));
+ handled = true;
+ }
+ }
+
+ if (chip->runtime_pm)
+ pm_runtime_put(map->dev);
+
+ if (handled)
+ return IRQ_HANDLED;
+ else
+ return IRQ_NONE;
+}
+
+static int regmap_irq_map(struct irq_domain *h, unsigned int virq,
+ irq_hw_number_t hw)
+{
+ struct regmap_irq_chip_data *data = h->host_data;
+
+ irq_set_chip_data(virq, data);
+ irq_set_chip(virq, &data->irq_chip);
+ irq_set_nested_thread(virq, 1);
+
+ /* ARM needs us to explicitly flag the IRQ as valid
+ * and will set them noprobe when we do so. */
+#ifdef CONFIG_ARM
+ set_irq_flags(virq, IRQF_VALID);
+#else
+ irq_set_noprobe(virq);
+#endif
+
+ return 0;
+}
+
+static struct irq_domain_ops regmap_domain_ops = {
+ .map = regmap_irq_map,
+ .xlate = irq_domain_xlate_twocell,
+};
+
+/**
+ * regmap_add_irq_chip(): Use standard regmap IRQ controller handling
+ *
+ * map: The regmap for the device.
+ * irq: The IRQ the device uses to signal interrupts
+ * irq_flags: The IRQF_ flags to use for the primary interrupt.
+ * chip: Configuration for the interrupt controller.
+ * data: Runtime data structure for the controller, allocated on success
+ *
+ * Returns 0 on success or an errno on failure.
+ *
+ * In order for this to be efficient the chip really should use a
+ * register cache. The chip driver is responsible for restoring the
+ * register values used by the IRQ controller over suspend and resume.
+ */
+int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
+ int irq_base, const struct regmap_irq_chip *chip,
+ struct regmap_irq_chip_data **data)
+{
+ struct regmap_irq_chip_data *d;
+ int i;
+ int ret = -ENOMEM;
+ u32 reg;
+
+ if (chip->num_regs <= 0)
+ return -EINVAL;
+
+ for (i = 0; i < chip->num_irqs; i++) {
+ if (chip->irqs[i].reg_offset % map->reg_stride)
+ return -EINVAL;
+ if (chip->irqs[i].reg_offset / map->reg_stride >=
+ chip->num_regs)
+ return -EINVAL;
+ }
+
+ if (irq_base) {
+ irq_base = irq_alloc_descs(irq_base, 0, chip->num_irqs, 0);
+ if (irq_base < 0) {
+ dev_warn(map->dev, "Failed to allocate IRQs: %d\n",
+ irq_base);
+ return irq_base;
+ }
+ }
+
+ d = kzalloc(sizeof(*d), GFP_KERNEL);
+ if (!d)
+ return -ENOMEM;
+
+ d->status_buf = kzalloc(sizeof(unsigned int) * chip->num_regs,
+ GFP_KERNEL);
+ if (!d->status_buf)
+ goto err_alloc;
+
+ d->mask_buf = kzalloc(sizeof(unsigned int) * chip->num_regs,
+ GFP_KERNEL);
+ if (!d->mask_buf)
+ goto err_alloc;
+
+ d->mask_buf_def = kzalloc(sizeof(unsigned int) * chip->num_regs,
+ GFP_KERNEL);
+ if (!d->mask_buf_def)
+ goto err_alloc;
+
+ if (chip->wake_base) {
+ d->wake_buf = kzalloc(sizeof(unsigned int) * chip->num_regs,
+ GFP_KERNEL);
+ if (!d->wake_buf)
+ goto err_alloc;
+ }
+
+ d->irq_chip = regmap_irq_chip;
+ d->irq_chip.name = chip->name;
+ d->irq = irq;
+ d->map = map;
+ d->chip = chip;
+ d->irq_base = irq_base;
+
+ if (chip->irq_reg_stride)
+ d->irq_reg_stride = chip->irq_reg_stride;
+ else
+ d->irq_reg_stride = 1;
+
+ if (!map->use_single_rw && map->reg_stride == 1 &&
+ d->irq_reg_stride == 1) {
+ d->status_reg_buf = kmalloc(map->format.val_bytes *
+ chip->num_regs, GFP_KERNEL);
+ if (!d->status_reg_buf)
+ goto err_alloc;
+ }
+
+ mutex_init(&d->lock);
+
+ for (i = 0; i < chip->num_irqs; i++)
+ d->mask_buf_def[chip->irqs[i].reg_offset / map->reg_stride]
+ |= chip->irqs[i].mask;
+
+ /* Mask all the interrupts by default */
+ for (i = 0; i < chip->num_regs; i++) {
+ d->mask_buf[i] = d->mask_buf_def[i];
+ reg = chip->mask_base +
+ (i * map->reg_stride * d->irq_reg_stride);
+ if (chip->mask_invert)
+ ret = regmap_update_bits(map, reg,
+ d->mask_buf[i], ~d->mask_buf[i]);
+ else
+ ret = regmap_update_bits(map, reg,
+ d->mask_buf[i], d->mask_buf[i]);
+ if (ret != 0) {
+ dev_err(map->dev, "Failed to set masks in 0x%x: %d\n",
+ reg, ret);
+ goto err_alloc;
+ }
+
+ if (!chip->init_ack_masked)
+ continue;
+
+ /* Ack masked but set interrupts */
+ reg = chip->status_base +
+ (i * map->reg_stride * d->irq_reg_stride);
+ ret = regmap_read(map, reg, &d->status_buf[i]);
+ if (ret != 0) {
+ dev_err(map->dev, "Failed to read IRQ status: %d\n",
+ ret);
+ goto err_alloc;
+ }
+
+ if (d->status_buf[i] && (chip->ack_base || chip->use_ack)) {
+ reg = chip->ack_base +
+ (i * map->reg_stride * d->irq_reg_stride);
+ ret = regmap_write(map, reg,
+ d->status_buf[i] & d->mask_buf[i]);
+ if (ret != 0) {
+ dev_err(map->dev, "Failed to ack 0x%x: %d\n",
+ reg, ret);
+ goto err_alloc;
+ }
+ }
+ }
+
+ /* Wake is disabled by default */
+ if (d->wake_buf) {
+ for (i = 0; i < chip->num_regs; i++) {
+ d->wake_buf[i] = d->mask_buf_def[i];
+ reg = chip->wake_base +
+ (i * map->reg_stride * d->irq_reg_stride);
+
+ if (chip->wake_invert)
+ ret = regmap_update_bits(map, reg,
+ d->mask_buf_def[i],
+ 0);
+ else
+ ret = regmap_update_bits(map, reg,
+ d->mask_buf_def[i],
+ d->wake_buf[i]);
+ if (ret != 0) {
+ dev_err(map->dev, "Failed to set masks in 0x%x: %d\n",
+ reg, ret);
+ goto err_alloc;
+ }
+ }
+ }
+
+ if (irq_base)
+ d->domain = irq_domain_add_legacy(map->dev->of_node,
+ chip->num_irqs, irq_base, 0,
+ &regmap_domain_ops, d);
+ else
+ d->domain = irq_domain_add_linear(map->dev->of_node,
+ chip->num_irqs,
+ &regmap_domain_ops, d);
+ if (!d->domain) {
+ dev_err(map->dev, "Failed to create IRQ domain\n");
+ ret = -ENOMEM;
+ goto err_alloc;
+ }
+
+ ret = request_threaded_irq(irq, NULL, regmap_irq_thread,
+ irq_flags | IRQF_ONESHOT,
+ chip->name, d);
+ if (ret != 0) {
+ dev_err(map->dev, "Failed to request IRQ %d for %s: %d\n",
+ irq, chip->name, ret);
+ goto err_domain;
+ }
+
+ *data = d;
+
+ return 0;
+
+err_domain:
+ /* Should really dispose of the domain but... */
+err_alloc:
+ kfree(d->wake_buf);
+ kfree(d->mask_buf_def);
+ kfree(d->mask_buf);
+ kfree(d->status_buf);
+ kfree(d->status_reg_buf);
+ kfree(d);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(regmap_add_irq_chip);
+
+/**
+ * regmap_del_irq_chip(): Stop interrupt handling for a regmap IRQ chip
+ *
+ * @irq: Primary IRQ for the device
+ * @d: regmap_irq_chip_data allocated by regmap_add_irq_chip()
+ */
+void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *d)
+{
+ if (!d)
+ return;
+
+ free_irq(irq, d);
+ irq_domain_remove(d->domain);
+ kfree(d->wake_buf);
+ kfree(d->mask_buf_def);
+ kfree(d->mask_buf);
+ kfree(d->status_reg_buf);
+ kfree(d->status_buf);
+ kfree(d);
+}
+EXPORT_SYMBOL_GPL(regmap_del_irq_chip);
+
+/**
+ * regmap_irq_chip_get_base(): Retrieve interrupt base for a regmap IRQ chip
+ *
+ * Useful for drivers to request their own IRQs.
+ *
+ * @data: regmap_irq controller to operate on.
+ */
+int regmap_irq_chip_get_base(struct regmap_irq_chip_data *data)
+{
+ WARN_ON(!data->irq_base);
+ return data->irq_base;
+}
+EXPORT_SYMBOL_GPL(regmap_irq_chip_get_base);
+
+/**
+ * regmap_irq_get_virq(): Map an interrupt on a chip to a virtual IRQ
+ *
+ * Useful for drivers to request their own IRQs.
+ *
+ * @data: regmap_irq controller to operate on.
+ * @irq: index of the interrupt requested in the chip IRQs
+ */
+int regmap_irq_get_virq(struct regmap_irq_chip_data *data, int irq)
+{
+ /* Handle holes in the IRQ list */
+ if (!data->chip->irqs[irq].mask)
+ return -EINVAL;
+
+ return irq_create_mapping(data->domain, irq);
+}
+EXPORT_SYMBOL_GPL(regmap_irq_get_virq);
+
+/**
+ * regmap_irq_get_domain(): Retrieve the irq_domain for the chip
+ *
+ * Useful for drivers to request their own IRQs and for integration
+ * with subsystems. For ease of integration NULL is accepted as a
+ * domain, allowing devices to just call this even if no domain is
+ * allocated.
+ *
+ * @data: regmap_irq controller to operate on.
+ */
+struct irq_domain *regmap_irq_get_domain(struct regmap_irq_chip_data *data)
+{
+ if (data)
+ return data->domain;
+ else
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(regmap_irq_get_domain);