2 * regmap based irq_chip
4 * Copyright 2011 Wolfson Microelectronics plc
6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
13 #include <linux/export.h>
14 #include <linux/regmap.h>
15 #include <linux/irq.h>
16 #include <linux/interrupt.h>
17 #include <linux/slab.h>
21 struct regmap_irq_chip_data {
25 struct regmap_irq_chip *chip;
30 unsigned int *status_buf;
31 unsigned int *mask_buf;
32 unsigned int *mask_buf_def;
36 struct regmap_irq *irq_to_regmap_irq(struct regmap_irq_chip_data *data,
39 return &data->chip->irqs[irq - data->irq_base];
42 static void regmap_irq_lock(struct irq_data *data)
44 struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);
49 static void regmap_irq_sync_unlock(struct irq_data *data)
51 struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);
55 * If there's been a change in the mask write it back to the
56 * hardware. We rely on the use of the regmap core cache to
57 * suppress pointless writes.
59 for (i = 0; i < d->chip->num_regs; i++) {
60 ret = regmap_update_bits(d->map, d->chip->mask_base + i,
61 d->mask_buf_def[i], d->mask_buf[i]);
63 dev_err(d->map->dev, "Failed to sync masks in %x\n",
64 d->chip->mask_base + i);
67 mutex_unlock(&d->lock);
70 static void regmap_irq_enable(struct irq_data *data)
72 struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);
73 const struct regmap_irq *irq_data = irq_to_regmap_irq(d, data->irq);
75 d->mask_buf[irq_data->reg_offset] &= ~irq_data->mask;
78 static void regmap_irq_disable(struct irq_data *data)
80 struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);
81 const struct regmap_irq *irq_data = irq_to_regmap_irq(d, data->irq);
83 d->mask_buf[irq_data->reg_offset] |= irq_data->mask;
86 static struct irq_chip regmap_irq_chip = {
88 .irq_bus_lock = regmap_irq_lock,
89 .irq_bus_sync_unlock = regmap_irq_sync_unlock,
90 .irq_disable = regmap_irq_disable,
91 .irq_enable = regmap_irq_enable,
94 static irqreturn_t regmap_irq_thread(int irq, void *d)
96 struct regmap_irq_chip_data *data = d;
97 struct regmap_irq_chip *chip = data->chip;
98 struct regmap *map = data->map;
100 u8 *buf8 = data->status_reg_buf;
101 u16 *buf16 = data->status_reg_buf;
102 u32 *buf32 = data->status_reg_buf;
104 ret = regmap_bulk_read(map, chip->status_base, data->status_reg_buf,
107 dev_err(map->dev, "Failed to read IRQ status: %d\n", ret);
112 * Ignore masked IRQs and ack if we need to; we ack early so
113 * there is no race between handling and acknowleding the
114 * interrupt. We assume that typically few of the interrupts
115 * will fire simultaneously so don't worry about overhead from
116 * doing a write per register.
118 for (i = 0; i < data->chip->num_regs; i++) {
119 switch (map->format.val_bytes) {
121 data->status_buf[i] = buf8[i];
124 data->status_buf[i] = buf16[i];
127 data->status_buf[i] = buf32[i];
134 data->status_buf[i] &= ~data->mask_buf[i];
136 if (data->status_buf[i] && chip->ack_base) {
137 ret = regmap_write(map, chip->ack_base + i,
138 data->status_buf[i]);
140 dev_err(map->dev, "Failed to ack 0x%x: %d\n",
141 chip->ack_base + i, ret);
145 for (i = 0; i < chip->num_irqs; i++) {
146 if (data->status_buf[chip->irqs[i].reg_offset] &
147 chip->irqs[i].mask) {
148 handle_nested_irq(data->irq_base + i);
156 * regmap_add_irq_chip(): Use standard regmap IRQ controller handling
158 * map: The regmap for the device.
159 * irq: The IRQ the device uses to signal interrupts
160 * irq_flags: The IRQF_ flags to use for the primary interrupt.
161 * chip: Configuration for the interrupt controller.
162 * data: Runtime data structure for the controller, allocated on success
164 * Returns 0 on success or an errno on failure.
166 * In order for this to be efficient the chip really should use a
167 * register cache. The chip driver is responsible for restoring the
168 * register values used by the IRQ controller over suspend and resume.
170 int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
171 int irq_base, struct regmap_irq_chip *chip,
172 struct regmap_irq_chip_data **data)
174 struct regmap_irq_chip_data *d;
178 irq_base = irq_alloc_descs(irq_base, 0, chip->num_irqs, 0);
180 dev_warn(map->dev, "Failed to allocate IRQs: %d\n",
185 d = kzalloc(sizeof(*d), GFP_KERNEL);
189 d->status_buf = kzalloc(sizeof(unsigned int) * chip->num_regs,
194 d->status_reg_buf = kzalloc(map->format.val_bytes * chip->num_regs,
196 if (!d->status_reg_buf)
199 d->mask_buf = kzalloc(sizeof(unsigned int) * chip->num_regs,
204 d->mask_buf_def = kzalloc(sizeof(unsigned int) * chip->num_regs,
206 if (!d->mask_buf_def)
211 d->irq_base = irq_base;
212 mutex_init(&d->lock);
214 for (i = 0; i < chip->num_irqs; i++)
215 d->mask_buf_def[chip->irqs[i].reg_offset]
216 |= chip->irqs[i].mask;
218 /* Mask all the interrupts by default */
219 for (i = 0; i < chip->num_regs; i++) {
220 d->mask_buf[i] = d->mask_buf_def[i];
221 ret = regmap_write(map, chip->mask_base + i, d->mask_buf[i]);
223 dev_err(map->dev, "Failed to set masks in 0x%x: %d\n",
224 chip->mask_base + i, ret);
229 /* Register them with genirq */
230 for (cur_irq = irq_base;
231 cur_irq < chip->num_irqs + irq_base;
233 irq_set_chip_data(cur_irq, d);
234 irq_set_chip_and_handler(cur_irq, ®map_irq_chip,
236 irq_set_nested_thread(cur_irq, 1);
238 /* ARM needs us to explicitly flag the IRQ as valid
239 * and will set them noprobe when we do so. */
241 set_irq_flags(cur_irq, IRQF_VALID);
243 irq_set_noprobe(cur_irq);
247 ret = request_threaded_irq(irq, NULL, regmap_irq_thread, irq_flags,
250 dev_err(map->dev, "Failed to request IRQ %d: %d\n", irq, ret);
257 kfree(d->mask_buf_def);
259 kfree(d->status_reg_buf);
260 kfree(d->status_buf);
264 EXPORT_SYMBOL_GPL(regmap_add_irq_chip);
267 * regmap_del_irq_chip(): Stop interrupt handling for a regmap IRQ chip
269 * @irq: Primary IRQ for the device
270 * @d: regmap_irq_chip_data allocated by regmap_add_irq_chip()
272 void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *d)
278 kfree(d->mask_buf_def);
280 kfree(d->status_reg_buf);
281 kfree(d->status_buf);
284 EXPORT_SYMBOL_GPL(regmap_del_irq_chip);