diff options
Diffstat (limited to 'drivers/mfd/lp8788-irq.c')
| -rw-r--r-- | drivers/mfd/lp8788-irq.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/drivers/mfd/lp8788-irq.c b/drivers/mfd/lp8788-irq.c new file mode 100644 index 000000000..792d51bae --- /dev/null +++ b/drivers/mfd/lp8788-irq.c @@ -0,0 +1,195 @@ +/* + * TI LP8788 MFD - interrupt handler + * + * Copyright 2012 Texas Instruments + * + * Author: Milo(Woogyom) Kim <milo.kim@ti.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/delay.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/irqdomain.h> +#include <linux/device.h> +#include <linux/mfd/lp8788.h> +#include <linux/module.h> +#include <linux/slab.h> + +/* register address */ +#define LP8788_INT_1 0x00 +#define LP8788_INTEN_1 0x03 + +#define BASE_INTEN_ADDR LP8788_INTEN_1 +#define SIZE_REG 8 +#define NUM_REGS 3 + +/* + * struct lp8788_irq_data + * @lp : used for accessing to lp8788 registers + * @irq_lock : mutex for enabling/disabling the interrupt + * @domain : IRQ domain for handling nested interrupt + * @enabled : status of enabled interrupt + */ +struct lp8788_irq_data { + struct lp8788 *lp; + struct mutex irq_lock; + struct irq_domain *domain; + int enabled[LP8788_INT_MAX]; +}; + +static inline u8 _irq_to_addr(enum lp8788_int_id id) +{ + return id / SIZE_REG; +} + +static inline u8 _irq_to_enable_addr(enum lp8788_int_id id) +{ + return _irq_to_addr(id) + BASE_INTEN_ADDR; +} + +static inline u8 _irq_to_mask(enum lp8788_int_id id) +{ + return 1 << (id % SIZE_REG); +} + +static inline u8 _irq_to_val(enum lp8788_int_id id, int enable) +{ + return enable << (id % SIZE_REG); +} + +static void lp8788_irq_enable(struct irq_data *data) +{ + struct lp8788_irq_data *irqd = irq_data_get_irq_chip_data(data); + + irqd->enabled[data->hwirq] = 1; +} + +static void lp8788_irq_disable(struct irq_data *data) +{ + struct lp8788_irq_data *irqd = irq_data_get_irq_chip_data(data); + + irqd->enabled[data->hwirq] = 0; +} + +static void lp8788_irq_bus_lock(struct irq_data *data) +{ + struct lp8788_irq_data *irqd = irq_data_get_irq_chip_data(data); + + mutex_lock(&irqd->irq_lock); +} + +static void lp8788_irq_bus_sync_unlock(struct irq_data *data) +{ + struct lp8788_irq_data *irqd = irq_data_get_irq_chip_data(data); + enum lp8788_int_id irq = data->hwirq; + u8 addr, mask, val; + + addr = _irq_to_enable_addr(irq); + mask = _irq_to_mask(irq); + val = _irq_to_val(irq, irqd->enabled[irq]); + + lp8788_update_bits(irqd->lp, addr, mask, val); + + mutex_unlock(&irqd->irq_lock); +} + +static struct irq_chip lp8788_irq_chip = { + .name = "lp8788", + .irq_enable = lp8788_irq_enable, + .irq_disable = lp8788_irq_disable, + .irq_bus_lock = lp8788_irq_bus_lock, + .irq_bus_sync_unlock = lp8788_irq_bus_sync_unlock, +}; + +static irqreturn_t lp8788_irq_handler(int irq, void *ptr) +{ + struct lp8788_irq_data *irqd = ptr; + struct lp8788 *lp = irqd->lp; + u8 status[NUM_REGS], addr, mask; + bool handled = false; + int i; + + if (lp8788_read_multi_bytes(lp, LP8788_INT_1, status, NUM_REGS)) + return IRQ_NONE; + + for (i = 0 ; i < LP8788_INT_MAX ; i++) { + addr = _irq_to_addr(i); + mask = _irq_to_mask(i); + + /* reporting only if the irq is enabled */ + if (status[addr] & mask) { + handle_nested_irq(irq_find_mapping(irqd->domain, i)); + handled = true; + } + } + + return handled ? IRQ_HANDLED : IRQ_NONE; +} + +static int lp8788_irq_map(struct irq_domain *d, unsigned int virq, + irq_hw_number_t hwirq) +{ + struct lp8788_irq_data *irqd = d->host_data; + struct irq_chip *chip = &lp8788_irq_chip; + + irq_set_chip_data(virq, irqd); + irq_set_chip_and_handler(virq, chip, handle_edge_irq); + irq_set_nested_thread(virq, 1); + irq_set_noprobe(virq); + + return 0; +} + +static const struct irq_domain_ops lp8788_domain_ops = { + .map = lp8788_irq_map, +}; + +int lp8788_irq_init(struct lp8788 *lp, int irq) +{ + struct lp8788_irq_data *irqd; + int ret; + + if (irq <= 0) { + dev_warn(lp->dev, "invalid irq number: %d\n", irq); + return 0; + } + + irqd = devm_kzalloc(lp->dev, sizeof(*irqd), GFP_KERNEL); + if (!irqd) + return -ENOMEM; + + irqd->lp = lp; + irqd->domain = irq_domain_add_linear(lp->dev->of_node, LP8788_INT_MAX, + &lp8788_domain_ops, irqd); + if (!irqd->domain) { + dev_err(lp->dev, "failed to add irq domain err\n"); + return -EINVAL; + } + + lp->irqdm = irqd->domain; + mutex_init(&irqd->irq_lock); + + ret = request_threaded_irq(irq, NULL, lp8788_irq_handler, + IRQF_TRIGGER_FALLING | IRQF_ONESHOT, + "lp8788-irq", irqd); + if (ret) { + dev_err(lp->dev, "failed to create a thread for IRQ_N\n"); + return ret; + } + + lp->irq = irq; + + return 0; +} + +void lp8788_irq_exit(struct lp8788 *lp) +{ + if (lp->irq) + free_irq(lp->irq, lp->irqdm); +} |