drivers/mfd/wm8994-irq.c

   1 /*
   2  * wm8994-irq.c  --  Interrupt controller support for Wolfson WM8994
   3  *
   4  * Copyright 2010 Wolfson Microelectronics PLC.
   5  *
   6  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   7  *
   8  *  This program is free software; you can redistribute  it and/or modify it
   9  *  under  the terms of  the GNU General  Public License as published by the
  10  *  Free Software Foundation;  either version 2 of the  License, or (at your
  11  *  option) any later version.
  12  *
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/i2c.h>
  18 #include <linux/irq.h>
  19 #include <linux/mfd/core.h>
  20 #include <linux/interrupt.h>
  21
  22 #include <linux/mfd/wm8994/core.h>
  23 #include <linux/mfd/wm8994/registers.h>
  24
  25 #include <linux/delay.h>
  26
  27 struct wm8994_irq_data {
  28         int reg;
  29         int mask;
  30 };
  31
  32 static struct wm8994_irq_data wm8994_irqs[] = {
  33         [WM8994_IRQ_TEMP_SHUT] = {
  34                 .reg = 2,
  35                 .mask = WM8994_TEMP_SHUT_EINT,
  36         },
  37         [WM8994_IRQ_MIC1_DET] = {
  38                 .reg = 2,
  39                 .mask = WM8994_MIC1_DET_EINT,
  40         },
  41         [WM8994_IRQ_MIC1_SHRT] = {
  42                 .reg = 2,
  43                 .mask = WM8994_MIC1_SHRT_EINT,
  44         },
  45         [WM8994_IRQ_MIC2_DET] = {
  46                 .reg = 2,
  47                 .mask = WM8994_MIC2_DET_EINT,
  48         },
  49         [WM8994_IRQ_MIC2_SHRT] = {
  50                 .reg = 2,
  51                 .mask = WM8994_MIC2_SHRT_EINT,
  52         },
  53         [WM8994_IRQ_FLL1_LOCK] = {
  54                 .reg = 2,
  55                 .mask = WM8994_FLL1_LOCK_EINT,
  56         },
  57         [WM8994_IRQ_FLL2_LOCK] = {
  58                 .reg = 2,
  59                 .mask = WM8994_FLL2_LOCK_EINT,
  60         },
  61         [WM8994_IRQ_SRC1_LOCK] = {
  62                 .reg = 2,
  63                 .mask = WM8994_SRC1_LOCK_EINT,
  64         },
  65         [WM8994_IRQ_SRC2_LOCK] = {
  66                 .reg = 2,
  67                 .mask = WM8994_SRC2_LOCK_EINT,
  68         },
  69         [WM8994_IRQ_AIF1DRC1_SIG_DET] = {
  70                 .reg = 2,
  71                 .mask = WM8994_AIF1DRC1_SIG_DET,
  72         },
  73         [WM8994_IRQ_AIF1DRC2_SIG_DET] = {
  74                 .reg = 2,
  75                 .mask = WM8994_AIF1DRC2_SIG_DET_EINT,
  76         },
  77         [WM8994_IRQ_AIF2DRC_SIG_DET] = {
  78                 .reg = 2,
  79                 .mask = WM8994_AIF2DRC_SIG_DET_EINT,
  80         },
  81         [WM8994_IRQ_FIFOS_ERR] = {
  82                 .reg = 2,
  83                 .mask = WM8994_FIFOS_ERR_EINT,
  84         },
  85         [WM8994_IRQ_WSEQ_DONE] = {
  86                 .reg = 2,
  87                 .mask = WM8994_WSEQ_DONE_EINT,
  88         },
  89         [WM8994_IRQ_DCS_DONE] = {
  90                 .reg = 2,
  91                 .mask = WM8994_DCS_DONE_EINT,
  92         },
  93         [WM8994_IRQ_TEMP_WARN] = {
  94                 .reg = 2,
  95                 .mask = WM8994_TEMP_WARN_EINT,
  96         },
  97         [WM8994_IRQ_GPIO(1)] = {
  98                 .reg = 1,
  99                 .mask = WM8994_GP1_EINT,
 100         },
 101         [WM8994_IRQ_GPIO(2)] = {
 102                 .reg = 1,
 103                 .mask = WM8994_GP2_EINT,
 104         },
 105         [WM8994_IRQ_GPIO(3)] = {
 106                 .reg = 1,
 107                 .mask = WM8994_GP3_EINT,
 108         },
 109         [WM8994_IRQ_GPIO(4)] = {
 110                 .reg = 1,
 111                 .mask = WM8994_GP4_EINT,
 112         },
 113         [WM8994_IRQ_GPIO(5)] = {
 114                 .reg = 1,
 115                 .mask = WM8994_GP5_EINT,
 116         },
 117         [WM8994_IRQ_GPIO(6)] = {
 118                 .reg = 1,
 119                 .mask = WM8994_GP6_EINT,
 120         },
 121         [WM8994_IRQ_GPIO(7)] = {
 122                 .reg = 1,
 123                 .mask = WM8994_GP7_EINT,
 124         },
 125         [WM8994_IRQ_GPIO(8)] = {
 126                 .reg = 1,
 127                 .mask = WM8994_GP8_EINT,
 128         },
 129         [WM8994_IRQ_GPIO(9)] = {
 130                 .reg = 1,
 131                 .mask = WM8994_GP8_EINT,
 132         },
 133         [WM8994_IRQ_GPIO(10)] = {
 134                 .reg = 1,
 135                 .mask = WM8994_GP10_EINT,
 136         },
 137         [WM8994_IRQ_GPIO(11)] = {
 138                 .reg = 1,
 139                 .mask = WM8994_GP11_EINT,
 140         },
 141 };
 142
 143 static inline int irq_data_to_status_reg(struct wm8994_irq_data *irq_data)
 144 {
 145         return WM8994_INTERRUPT_STATUS_1 - 1 + irq_data->reg;
 146 }
 147
 148 static inline int irq_data_to_mask_reg(struct wm8994_irq_data *irq_data)
 149 {
 150         return WM8994_INTERRUPT_STATUS_1_MASK - 1 + irq_data->reg;
 151 }
 152
 153 static inline struct wm8994_irq_data *irq_to_wm8994_irq(struct wm8994 *wm8994,
 154                                                         int irq)
 155 {
 156         return &wm8994_irqs[irq - wm8994->irq_base];
 157 }
 158
 159 static void wm8994_irq_lock(struct irq_data *data)
 160 {
 161         struct wm8994 *wm8994 = irq_data_get_irq_chip_data(data);
 162
 163         mutex_lock(&wm8994->irq_lock);
 164 }
 165
 166 static void wm8994_irq_sync_unlock(struct irq_data *data)
 167 {
 168         struct wm8994 *wm8994 = irq_data_get_irq_chip_data(data);
 169         int i;
 170
 171         for (i = 0; i < ARRAY_SIZE(wm8994->irq_masks_cur); i++) {
 172                 /* If there's been a change in the mask write it back
 173                  * to the hardware. */
 174                 if (wm8994->irq_masks_cur[i] != wm8994->irq_masks_cache[i]) {
 175                         wm8994->irq_masks_cache[i] = wm8994->irq_masks_cur[i];
 176                         wm8994_reg_write(wm8994,
 177                                          WM8994_INTERRUPT_STATUS_1_MASK + i,
 178                                          wm8994->irq_masks_cur[i]);
 179                 }
 180         }
 181
 182         mutex_unlock(&wm8994->irq_lock);
 183 }
 184
 185 static void wm8994_irq_enable(struct irq_data *data)
 186 {
 187         struct wm8994 *wm8994 = irq_data_get_irq_chip_data(data);
 188         struct wm8994_irq_data *irq_data = irq_to_wm8994_irq(wm8994,
 189                                                              data->irq);
 190
 191         wm8994->irq_masks_cur[irq_data->reg - 1] &= ~irq_data->mask;
 192 }
 193
 194 static void wm8994_irq_disable(struct irq_data *data)
 195 {
 196         struct wm8994 *wm8994 = irq_data_get_irq_chip_data(data);
 197         struct wm8994_irq_data *irq_data = irq_to_wm8994_irq(wm8994,
 198                                                              data->irq);
 199
 200         wm8994->irq_masks_cur[irq_data->reg - 1] |= irq_data->mask;
 201 }
 202
 203 static struct irq_chip wm8994_irq_chip = {
 204         .name                   = "wm8994",
 205         .irq_bus_lock           = wm8994_irq_lock,
 206         .irq_bus_sync_unlock    = wm8994_irq_sync_unlock,
 207         .irq_disable            = wm8994_irq_disable,
 208         .irq_enable             = wm8994_irq_enable,
 209 };
 210
 211 /* The processing of the primary interrupt occurs in a thread so that
 212  * we can interact with the device over I2C or SPI. */
 213 static irqreturn_t wm8994_irq_thread(int irq, void *data)
 214 {
 215         struct wm8994 *wm8994 = data;
 216         unsigned int i;
 217         u16 status[WM8994_NUM_IRQ_REGS];
 218         int ret;
 219
 220         ret = wm8994_bulk_read(wm8994, WM8994_INTERRUPT_STATUS_1,
 221                                WM8994_NUM_IRQ_REGS, status);
 222         if (ret < 0) {
 223                 dev_err(wm8994->dev, "Failed to read interrupt status: %d\n",
 224                         ret);
 225                 return IRQ_NONE;
 226         }
 227
 228         /* Bit swap and apply masking */
 229         for (i = 0; i < WM8994_NUM_IRQ_REGS; i++) {
 230                 status[i] = be16_to_cpu(status[i]);
 231                 status[i] &= ~wm8994->irq_masks_cur[i];
 232         }
 233
 234         /* Ack any unmasked IRQs */
 235         for (i = 0; i < ARRAY_SIZE(status); i++) {
 236                 if (status[i])
 237                         wm8994_reg_write(wm8994, WM8994_INTERRUPT_STATUS_1 + i,
 238                                          status[i]);
 239         }
 240
 241         /* Report */
 242         for (i = 0; i < ARRAY_SIZE(wm8994_irqs); i++) {
 243                 if (status[wm8994_irqs[i].reg - 1] & wm8994_irqs[i].mask)
 244                         handle_nested_irq(wm8994->irq_base + i);
 245         }
 246
 247         return IRQ_HANDLED;
 248 }
 249
 250 int wm8994_irq_init(struct wm8994 *wm8994)
 251 {
 252         int i, cur_irq, ret;
 253
 254         mutex_init(&wm8994->irq_lock);
 255
 256         /* Mask the individual interrupt sources */
 257         for (i = 0; i < ARRAY_SIZE(wm8994->irq_masks_cur); i++) {
 258                 wm8994->irq_masks_cur[i] = 0xffff;
 259                 wm8994->irq_masks_cache[i] = 0xffff;
 260                 wm8994_reg_write(wm8994, WM8994_INTERRUPT_STATUS_1_MASK + i,
 261                                  0xffff);
 262         }
 263
 264         if (!wm8994->irq) {
 265                 dev_warn(wm8994->dev,
 266                          "No interrupt specified, no interrupts\n");
 267                 wm8994->irq_base = 0;
 268                 return 0;
 269         }
 270
 271         if (!wm8994->irq_base) {
 272                 dev_err(wm8994->dev,
 273                         "No interrupt base specified, no interrupts\n");
 274                 return 0;
 275         }
 276
 277         /* Register them with genirq */
 278         for (cur_irq = wm8994->irq_base;
 279              cur_irq < ARRAY_SIZE(wm8994_irqs) + wm8994->irq_base;
 280              cur_irq++) {
 281                 irq_set_chip_data(cur_irq, wm8994);
 282                 irq_set_chip_and_handler(cur_irq, &wm8994_irq_chip,
 283                                          handle_edge_irq);
 284                 irq_set_nested_thread(cur_irq, 1);
 285
 286                 /* ARM needs us to explicitly flag the IRQ as valid
 287                  * and will set them noprobe when we do so. */
 288 #ifdef CONFIG_ARM
 289                 set_irq_flags(cur_irq, IRQF_VALID);
 290 #else
 291                 irq_set_noprobe(cur_irq);
 292 #endif
 293         }
 294
 295         ret = request_threaded_irq(wm8994->irq, NULL, wm8994_irq_thread,
 296                                    IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
 297                                    "wm8994", wm8994);
 298         if (ret != 0) {
 299                 dev_err(wm8994->dev, "Failed to request IRQ %d: %d\n",
 300                         wm8994->irq, ret);
 301                 return ret;
 302         }
 303
 304         /* Enable top level interrupt if it was masked */
 305         wm8994_reg_write(wm8994, WM8994_INTERRUPT_CONTROL, 0);
 306
 307         return 0;
 308 }
 309
 310 void wm8994_irq_exit(struct wm8994 *wm8994)
 311 {
 312         if (wm8994->irq)
 313                 free_irq(wm8994->irq, wm8994);
 314 }