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 struct wm8994_irq_data *irq_to_wm8994_irq(struct wm8994 *wm8994,
 144                                                         int irq)
 145 {
 146         return &wm8994_irqs[irq - wm8994->irq_base];
 147 }
 148
 149 static void wm8994_irq_lock(struct irq_data *data)
 150 {
 151         struct wm8994 *wm8994 = irq_data_get_irq_chip_data(data);
 152
 153         mutex_lock(&wm8994->irq_lock);
 154 }
 155
 156 static void wm8994_irq_sync_unlock(struct irq_data *data)
 157 {
 158         struct wm8994 *wm8994 = irq_data_get_irq_chip_data(data);
 159         int i;
 160
 161         for (i = 0; i < ARRAY_SIZE(wm8994->irq_masks_cur); i++) {
 162                 /* If there's been a change in the mask write it back
 163                  * to the hardware. */
 164                 if (wm8994->irq_masks_cur[i] != wm8994->irq_masks_cache[i]) {
 165                         wm8994->irq_masks_cache[i] = wm8994->irq_masks_cur[i];
 166                         wm8994_reg_write(wm8994,
 167                                          WM8994_INTERRUPT_STATUS_1_MASK + i,
 168                                          wm8994->irq_masks_cur[i]);
 169                 }
 170         }
 171
 172         mutex_unlock(&wm8994->irq_lock);
 173 }
 174
 175 static void wm8994_irq_enable(struct irq_data *data)
 176 {
 177         struct wm8994 *wm8994 = irq_data_get_irq_chip_data(data);
 178         struct wm8994_irq_data *irq_data = irq_to_wm8994_irq(wm8994,
 179                                                              data->irq);
 180
 181         wm8994->irq_masks_cur[irq_data->reg - 1] &= ~irq_data->mask;
 182 }
 183
 184 static void wm8994_irq_disable(struct irq_data *data)
 185 {
 186         struct wm8994 *wm8994 = irq_data_get_irq_chip_data(data);
 187         struct wm8994_irq_data *irq_data = irq_to_wm8994_irq(wm8994,
 188                                                              data->irq);
 189
 190         wm8994->irq_masks_cur[irq_data->reg - 1] |= irq_data->mask;
 191 }
 192
 193 static struct irq_chip wm8994_irq_chip = {
 194         .name                   = "wm8994",
 195         .irq_bus_lock           = wm8994_irq_lock,
 196         .irq_bus_sync_unlock    = wm8994_irq_sync_unlock,
 197         .irq_disable            = wm8994_irq_disable,
 198         .irq_enable             = wm8994_irq_enable,
 199 };
 200
 201 /* The processing of the primary interrupt occurs in a thread so that
 202  * we can interact with the device over I2C or SPI. */
 203 static irqreturn_t wm8994_irq_thread(int irq, void *data)
 204 {
 205         struct wm8994 *wm8994 = data;
 206         unsigned int i;
 207         u16 status[WM8994_NUM_IRQ_REGS];
 208         int ret;
 209
 210         ret = wm8994_bulk_read(wm8994, WM8994_INTERRUPT_STATUS_1,
 211                                WM8994_NUM_IRQ_REGS, status);
 212         if (ret < 0) {
 213                 dev_err(wm8994->dev, "Failed to read interrupt status: %d\n",
 214                         ret);
 215                 return IRQ_NONE;
 216         }
 217
 218         /* Bit swap and apply masking */
 219         for (i = 0; i < WM8994_NUM_IRQ_REGS; i++) {
 220                 status[i] = be16_to_cpu(status[i]);
 221                 status[i] &= ~wm8994->irq_masks_cur[i];
 222         }
 223
 224         /* Ack any unmasked IRQs */
 225         for (i = 0; i < ARRAY_SIZE(status); i++) {
 226                 if (status[i])
 227                         wm8994_reg_write(wm8994, WM8994_INTERRUPT_STATUS_1 + i,
 228                                          status[i]);
 229         }
 230
 231         /* Report */
 232         for (i = 0; i < ARRAY_SIZE(wm8994_irqs); i++) {
 233                 if (status[wm8994_irqs[i].reg - 1] & wm8994_irqs[i].mask)
 234                         handle_nested_irq(wm8994->irq_base + i);
 235         }
 236
 237         return IRQ_HANDLED;
 238 }
 239
 240 int wm8994_irq_init(struct wm8994 *wm8994)
 241 {
 242         int i, cur_irq, ret;
 243
 244         mutex_init(&wm8994->irq_lock);
 245
 246         /* Mask the individual interrupt sources */
 247         for (i = 0; i < ARRAY_SIZE(wm8994->irq_masks_cur); i++) {
 248                 wm8994->irq_masks_cur[i] = 0xffff;
 249                 wm8994->irq_masks_cache[i] = 0xffff;
 250                 wm8994_reg_write(wm8994, WM8994_INTERRUPT_STATUS_1_MASK + i,
 251                                  0xffff);
 252         }
 253
 254         if (!wm8994->irq) {
 255                 dev_warn(wm8994->dev,
 256                          "No interrupt specified, no interrupts\n");
 257                 wm8994->irq_base = 0;
 258                 return 0;
 259         }
 260
 261         if (!wm8994->irq_base) {
 262                 dev_err(wm8994->dev,
 263                         "No interrupt base specified, no interrupts\n");
 264                 return 0;
 265         }
 266
 267         /* Register them with genirq */
 268         for (cur_irq = wm8994->irq_base;
 269              cur_irq < ARRAY_SIZE(wm8994_irqs) + wm8994->irq_base;
 270              cur_irq++) {
 271                 irq_set_chip_data(cur_irq, wm8994);
 272                 irq_set_chip_and_handler(cur_irq, &wm8994_irq_chip,
 273                                          handle_edge_irq);
 274                 irq_set_nested_thread(cur_irq, 1);
 275
 276                 /* ARM needs us to explicitly flag the IRQ as valid
 277                  * and will set them noprobe when we do so. */
 278 #ifdef CONFIG_ARM
 279                 set_irq_flags(cur_irq, IRQF_VALID);
 280 #else
 281                 irq_set_noprobe(cur_irq);
 282 #endif
 283         }
 284
 285         ret = request_threaded_irq(wm8994->irq, NULL, wm8994_irq_thread,
 286                                    IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
 287                                    "wm8994", wm8994);
 288         if (ret != 0) {
 289                 dev_err(wm8994->dev, "Failed to request IRQ %d: %d\n",
 290                         wm8994->irq, ret);
 291                 return ret;
 292         }
 293
 294         /* Enable top level interrupt if it was masked */
 295         wm8994_reg_write(wm8994, WM8994_INTERRUPT_CONTROL, 0);
 296
 297         return 0;
 298 }
 299
 300 void wm8994_irq_exit(struct wm8994 *wm8994)
 301 {
 302         if (wm8994->irq)
 303                 free_irq(wm8994->irq, wm8994);
 304 }