Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / base / regmap / regmap-irq.c
diff --git a/kernel/drivers/base/regmap/regmap-irq.c b/kernel/drivers/base/regmap/regmap-irq.c
new file mode 100644 (file)
index 0000000..a6c3f75
--- /dev/null
@@ -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);