drivers/mfd/tps65910-irq.c

   1 /*
   2  * tps65910-irq.c  --  TI TPS6591x
   3  *
   4  * Copyright 2010 Texas Instruments Inc.
   5  *
   6  * Author: Graeme Gregory <gg@slimlogic.co.uk>
   7  * Author: Jorge Eduardo Candelaria <jedu@slimlogic.co.uk>
   8  *
   9  *  This program is free software; you can redistribute it and/or modify it
  10  *  under  the terms of the GNU General  Public License as published by the
  11  *  Free Software Foundation;  either version 2 of the License, or (at your
  12  *  option) any later version.
  13  *
  14  */
  15
  16 #include <linux/kernel.h>
  17 #include <linux/module.h>
  18 #include <linux/init.h>
  19 #include <linux/bug.h>
  20 #include <linux/device.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/irq.h>
  23 #include <linux/gpio.h>
  24 #include <linux/mfd/tps65910.h>
  25
  26 static inline int irq_to_tps65910_irq(struct tps65910 *tps65910,
  27                                                         int irq)
  28 {
  29         return (irq - tps65910->irq_base);
  30 }
  31
  32 /*
  33  * This is a threaded IRQ handler so can access I2C/SPI.  Since all
  34  * interrupts are clear on read the IRQ line will be reasserted and
  35  * the physical IRQ will be handled again if another interrupt is
  36  * asserted while we run - in the normal course of events this is a
  37  * rare occurrence so we save I2C/SPI reads.  We're also assuming that
  38  * it's rare to get lots of interrupts firing simultaneously so try to
  39  * minimise I/O.
  40  */
  41 static irqreturn_t tps65910_irq(int irq, void *irq_data)
  42 {
  43         struct tps65910 *tps65910 = irq_data;
  44         u32 irq_sts;
  45         u32 irq_mask;
  46         u8 reg;
  47         int i;
  48
  49         tps65910->read(tps65910, TPS65910_INT_STS, 1, &reg);
  50         irq_sts = reg;
  51         tps65910->read(tps65910, TPS65910_INT_STS2, 1, &reg);
  52         irq_sts |= reg << 8;
  53         switch (tps65910_chip_id(tps65910)) {
  54         case TPS65911:
  55                 tps65910->read(tps65910, TPS65910_INT_STS3, 1, &reg);
  56                 irq_sts |= reg << 16;
  57         }
  58
  59         tps65910->read(tps65910, TPS65910_INT_MSK, 1, &reg);
  60         irq_mask = reg;
  61         tps65910->read(tps65910, TPS65910_INT_MSK2, 1, &reg);
  62         irq_mask |= reg << 8;
  63         switch (tps65910_chip_id(tps65910)) {
  64         case TPS65911:
  65                 tps65910->read(tps65910, TPS65910_INT_MSK3, 1, &reg);
  66                 irq_mask |= reg << 16;
  67         }
  68
  69         irq_sts &= ~irq_mask;
  70
  71         if (!irq_sts)
  72                 return IRQ_NONE;
  73
  74         for (i = 0; i < tps65910->irq_num; i++) {
  75
  76                 if (!(irq_sts & (1 << i)))
  77                         continue;
  78
  79                 handle_nested_irq(tps65910->irq_base + i);
  80         }
  81
  82         /* Write the STS register back to clear IRQs we handled */
  83         reg = irq_sts & 0xFF;
  84         irq_sts >>= 8;
  85         tps65910->write(tps65910, TPS65910_INT_STS, 1, &reg);
  86         reg = irq_sts & 0xFF;
  87         tps65910->write(tps65910, TPS65910_INT_STS2, 1, &reg);
  88         switch (tps65910_chip_id(tps65910)) {
  89         case TPS65911:
  90                 reg = irq_sts >> 8;
  91                 tps65910->write(tps65910, TPS65910_INT_STS3, 1, &reg);
  92         }
  93
  94         return IRQ_HANDLED;
  95 }
  96
  97 static void tps65910_irq_lock(struct irq_data *data)
  98 {
  99         struct tps65910 *tps65910 = irq_data_get_irq_chip_data(data);
 100
 101         mutex_lock(&tps65910->irq_lock);
 102 }
 103
 104 static void tps65910_irq_sync_unlock(struct irq_data *data)
 105 {
 106         struct tps65910 *tps65910 = irq_data_get_irq_chip_data(data);
 107         u32 reg_mask;
 108         u8 reg;
 109
 110         tps65910->read(tps65910, TPS65910_INT_MSK, 1, &reg);
 111         reg_mask = reg;
 112         tps65910->read(tps65910, TPS65910_INT_MSK2, 1, &reg);
 113         reg_mask |= reg << 8;
 114         switch (tps65910_chip_id(tps65910)) {
 115         case TPS65911:
 116                 tps65910->read(tps65910, TPS65910_INT_MSK3, 1, &reg);
 117                 reg_mask |= reg << 16;
 118         }
 119
 120         if (tps65910->irq_mask != reg_mask) {
 121                 reg = tps65910->irq_mask & 0xFF;
 122                 tps65910->write(tps65910, TPS65910_INT_MSK, 1, &reg);
 123                 reg = tps65910->irq_mask >> 8 & 0xFF;
 124                 tps65910->write(tps65910, TPS65910_INT_MSK2, 1, &reg);
 125                 switch (tps65910_chip_id(tps65910)) {
 126                 case TPS65911:
 127                         reg = tps65910->irq_mask >> 16;
 128                         tps65910->write(tps65910, TPS65910_INT_MSK3, 1, &reg);
 129                 }
 130         }
 131         mutex_unlock(&tps65910->irq_lock);
 132 }
 133
 134 static void tps65910_irq_enable(struct irq_data *data)
 135 {
 136         struct tps65910 *tps65910 = irq_data_get_irq_chip_data(data);
 137
 138         tps65910->irq_mask &= ~( 1 << irq_to_tps65910_irq(tps65910, data->irq));
 139 }
 140
 141 static void tps65910_irq_disable(struct irq_data *data)
 142 {
 143         struct tps65910 *tps65910 = irq_data_get_irq_chip_data(data);
 144
 145         tps65910->irq_mask |= ( 1 << irq_to_tps65910_irq(tps65910, data->irq));
 146 }
 147
 148 static struct irq_chip tps65910_irq_chip = {
 149         .name = "tps65910",
 150         .irq_bus_lock = tps65910_irq_lock,
 151         .irq_bus_sync_unlock = tps65910_irq_sync_unlock,
 152         .irq_disable = tps65910_irq_disable,
 153         .irq_enable = tps65910_irq_enable,
 154 };
 155
 156 int tps65910_irq_init(struct tps65910 *tps65910, int irq,
 157                     struct tps65910_platform_data *pdata)
 158 {
 159         int ret, cur_irq;
 160         int flags = IRQF_ONESHOT;
 161
 162         if (!irq) {
 163                 dev_warn(tps65910->dev, "No interrupt support, no core IRQ\n");
 164                 return -EINVAL;
 165         }
 166
 167         if (!pdata || !pdata->irq_base) {
 168                 dev_warn(tps65910->dev, "No interrupt support, no IRQ base\n");
 169                 return -EINVAL;
 170         }
 171
 172         tps65910->irq_mask = 0xFFFFFF;
 173
 174         mutex_init(&tps65910->irq_lock);
 175         tps65910->chip_irq = irq;
 176         tps65910->irq_base = pdata->irq_base;
 177
 178         switch (tps65910_chip_id(tps65910)) {
 179         case TPS65910:
 180                 tps65910->irq_num = TPS65910_NUM_IRQ;
 181         case TPS65911:
 182                 tps65910->irq_num = TPS65911_NUM_IRQ;
 183         }
 184
 185         /* Register with genirq */
 186         for (cur_irq = tps65910->irq_base;
 187              cur_irq < tps65910->irq_num + tps65910->irq_base;
 188              cur_irq++) {
 189                 irq_set_chip_data(cur_irq, tps65910);
 190                 irq_set_chip_and_handler(cur_irq, &tps65910_irq_chip,
 191                                          handle_edge_irq);
 192                 irq_set_nested_thread(cur_irq, 1);
 193
 194                 /* ARM needs us to explicitly flag the IRQ as valid
 195                  * and will set them noprobe when we do so. */
 196 #ifdef CONFIG_ARM
 197                 set_irq_flags(cur_irq, IRQF_VALID);
 198 #else
 199                 irq_set_noprobe(cur_irq);
 200 #endif
 201         }
 202
 203         ret = request_threaded_irq(irq, NULL, tps65910_irq, flags,
 204                                    "tps65910", tps65910);
 205
 206         irq_set_irq_type(irq, IRQ_TYPE_LEVEL_LOW);
 207
 208         if (ret != 0)
 209                 dev_err(tps65910->dev, "Failed to request IRQ: %d\n", ret);
 210
 211         return ret;
 212 }
 213
 214 int tps65910_irq_exit(struct tps65910 *tps65910)
 215 {
 216         free_irq(tps65910->chip_irq, tps65910);
 217         return 0;
 218 }