diff options
Diffstat (limited to 'drivers/base/regmap/regmap-irq.c')
-rw-r--r-- | drivers/base/regmap/regmap-irq.c | 599 |
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, + ®map_domain_ops, d); + else + d->domain = irq_domain_add_linear(map->dev->of_node, + chip->num_irqs, + ®map_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); |