1 /* 2 * TI LP8788 MFD - interrupt handler 3 * 4 * Copyright 2012 Texas Instruments 5 * 6 * Author: Milo(Woogyom) Kim <milo.kim@ti.com> 7 * 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. 11 * 12 */ 13 14 #include <linux/delay.h> 15 #include <linux/err.h> 16 #include <linux/interrupt.h> 17 #include <linux/irq.h> 18 #include <linux/irqdomain.h> 19 #include <linux/device.h> 20 #include <linux/mfd/lp8788.h> 21 #include <linux/module.h> 22 #include <linux/slab.h> 23 24 /* register address */ 25 #define LP8788_INT_1 0x00 26 #define LP8788_INTEN_1 0x03 27 28 #define BASE_INTEN_ADDR LP8788_INTEN_1 29 #define SIZE_REG 8 30 #define NUM_REGS 3 31 32 /* 33 * struct lp8788_irq_data 34 * @lp : used for accessing to lp8788 registers 35 * @irq_lock : mutex for enabling/disabling the interrupt 36 * @domain : IRQ domain for handling nested interrupt 37 * @enabled : status of enabled interrupt 38 */ 39 struct lp8788_irq_data { 40 struct lp8788 *lp; 41 struct mutex irq_lock; 42 struct irq_domain *domain; 43 int enabled[LP8788_INT_MAX]; 44 }; 45 46 static inline u8 _irq_to_addr(enum lp8788_int_id id) 47 { 48 return id / SIZE_REG; 49 } 50 51 static inline u8 _irq_to_enable_addr(enum lp8788_int_id id) 52 { 53 return _irq_to_addr(id) + BASE_INTEN_ADDR; 54 } 55 56 static inline u8 _irq_to_mask(enum lp8788_int_id id) 57 { 58 return 1 << (id % SIZE_REG); 59 } 60 61 static inline u8 _irq_to_val(enum lp8788_int_id id, int enable) 62 { 63 return enable << (id % SIZE_REG); 64 } 65 66 static void lp8788_irq_enable(struct irq_data *data) 67 { 68 struct lp8788_irq_data *irqd = irq_data_get_irq_chip_data(data); 69 70 irqd->enabled[data->hwirq] = 1; 71 } 72 73 static void lp8788_irq_disable(struct irq_data *data) 74 { 75 struct lp8788_irq_data *irqd = irq_data_get_irq_chip_data(data); 76 77 irqd->enabled[data->hwirq] = 0; 78 } 79 80 static void lp8788_irq_bus_lock(struct irq_data *data) 81 { 82 struct lp8788_irq_data *irqd = irq_data_get_irq_chip_data(data); 83 84 mutex_lock(&irqd->irq_lock); 85 } 86 87 static void lp8788_irq_bus_sync_unlock(struct irq_data *data) 88 { 89 struct lp8788_irq_data *irqd = irq_data_get_irq_chip_data(data); 90 enum lp8788_int_id irq = data->hwirq; 91 u8 addr, mask, val; 92 93 addr = _irq_to_enable_addr(irq); 94 mask = _irq_to_mask(irq); 95 val = _irq_to_val(irq, irqd->enabled[irq]); 96 97 lp8788_update_bits(irqd->lp, addr, mask, val); 98 99 mutex_unlock(&irqd->irq_lock); 100 } 101 102 static struct irq_chip lp8788_irq_chip = { 103 .name = "lp8788", 104 .irq_enable = lp8788_irq_enable, 105 .irq_disable = lp8788_irq_disable, 106 .irq_bus_lock = lp8788_irq_bus_lock, 107 .irq_bus_sync_unlock = lp8788_irq_bus_sync_unlock, 108 }; 109 110 static irqreturn_t lp8788_irq_handler(int irq, void *ptr) 111 { 112 struct lp8788_irq_data *irqd = ptr; 113 struct lp8788 *lp = irqd->lp; 114 u8 status[NUM_REGS], addr, mask; 115 bool handled; 116 int i; 117 118 if (lp8788_read_multi_bytes(lp, LP8788_INT_1, status, NUM_REGS)) 119 return IRQ_NONE; 120 121 for (i = 0 ; i < LP8788_INT_MAX ; i++) { 122 addr = _irq_to_addr(i); 123 mask = _irq_to_mask(i); 124 125 /* reporting only if the irq is enabled */ 126 if (status[addr] & mask) { 127 handle_nested_irq(irq_find_mapping(irqd->domain, i)); 128 handled = true; 129 } 130 } 131 132 return handled ? IRQ_HANDLED : IRQ_NONE; 133 } 134 135 static int lp8788_irq_map(struct irq_domain *d, unsigned int virq, 136 irq_hw_number_t hwirq) 137 { 138 struct lp8788_irq_data *irqd = d->host_data; 139 struct irq_chip *chip = &lp8788_irq_chip; 140 141 irq_set_chip_data(virq, irqd); 142 irq_set_chip_and_handler(virq, chip, handle_edge_irq); 143 irq_set_nested_thread(virq, 1); 144 irq_set_noprobe(virq); 145 146 return 0; 147 } 148 149 static const struct irq_domain_ops lp8788_domain_ops = { 150 .map = lp8788_irq_map, 151 }; 152 153 int lp8788_irq_init(struct lp8788 *lp, int irq) 154 { 155 struct lp8788_irq_data *irqd; 156 int ret; 157 158 if (irq <= 0) { 159 dev_warn(lp->dev, "invalid irq number: %d\n", irq); 160 return 0; 161 } 162 163 irqd = devm_kzalloc(lp->dev, sizeof(*irqd), GFP_KERNEL); 164 if (!irqd) 165 return -ENOMEM; 166 167 irqd->lp = lp; 168 irqd->domain = irq_domain_add_linear(lp->dev->of_node, LP8788_INT_MAX, 169 &lp8788_domain_ops, irqd); 170 if (!irqd->domain) { 171 dev_err(lp->dev, "failed to add irq domain err\n"); 172 return -EINVAL; 173 } 174 175 lp->irqdm = irqd->domain; 176 mutex_init(&irqd->irq_lock); 177 178 ret = request_threaded_irq(irq, NULL, lp8788_irq_handler, 179 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 180 "lp8788-irq", irqd); 181 if (ret) { 182 dev_err(lp->dev, "failed to create a thread for IRQ_N\n"); 183 return ret; 184 } 185 186 lp->irq = irq; 187 188 return 0; 189 } 190 191 void lp8788_irq_exit(struct lp8788 *lp) 192 { 193 if (lp->irq) 194 free_irq(lp->irq, lp->irqdm); 195 } 196