drivers/mfd/twl6030-irq.c

   1 /*
   2  * twl6030-irq.c - TWL6030 irq support
   3  *
   4  * Copyright (C) 2005-2009 Texas Instruments, Inc.
   5  *
   6  * Modifications to defer interrupt handling to a kernel thread:
   7  * Copyright (C) 2006 MontaVista Software, Inc.
   8  *
   9  * Based on tlv320aic23.c:
  10  * Copyright (c) by Kai Svahn <kai.svahn@nokia.com>
  11  *
  12  * Code cleanup and modifications to IRQ handler.
  13  * by syed khasim <x0khasim@ti.com>
  14  *
  15  * TWL6030 specific code and IRQ handling changes by
  16  * Jagadeesh Bhaskar Pakaravoor <j-pakaravoor@ti.com>
  17  * Balaji T K <balajitk@ti.com>
  18  *
  19  * This program is free software; you can redistribute it and/or modify
  20  * it under the terms of the GNU General Public License as published by
  21  * the Free Software Foundation; either version 2 of the License, or
  22  * (at your option) any later version.
  23  *
  24  * This program is distributed in the hope that it will be useful,
  25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27  * GNU General Public License for more details.
  28  *
  29  * You should have received a copy of the GNU General Public License
  30  * along with this program; if not, write to the Free Software
  31  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  32  */
  33
  34 #include <linux/export.h>
  35 #include <linux/interrupt.h>
  36 #include <linux/irq.h>
  37 #include <linux/kthread.h>
  38 #include <linux/i2c/twl.h>
  39 #include <linux/platform_device.h>
  40 #include <linux/suspend.h>
  41 #include <linux/of.h>
  42 #include <linux/irqdomain.h>
  43 #include <linux/of_device.h>
  44
  45 #include "twl-core.h"
  46
  47 /*
  48  * TWL6030 (unlike its predecessors, which had two level interrupt handling)
  49  * three interrupt registers INT_STS_A, INT_STS_B and INT_STS_C.
  50  * It exposes status bits saying who has raised an interrupt. There are
  51  * three mask registers that corresponds to these status registers, that
  52  * enables/disables these interrupts.
  53  *
  54  * We set up IRQs starting at a platform-specified base. An interrupt map table,
  55  * specifies mapping between interrupt number and the associated module.
  56  */
  57 #define TWL6030_NR_IRQS    20
  58
  59 static int twl6030_interrupt_mapping[24] = {
  60         PWR_INTR_OFFSET,        /* Bit 0        PWRON                   */
  61         PWR_INTR_OFFSET,        /* Bit 1        RPWRON                  */
  62         PWR_INTR_OFFSET,        /* Bit 2        BAT_VLOW                */
  63         RTC_INTR_OFFSET,        /* Bit 3        RTC_ALARM               */
  64         RTC_INTR_OFFSET,        /* Bit 4        RTC_PERIOD              */
  65         HOTDIE_INTR_OFFSET,     /* Bit 5        HOT_DIE                 */
  66         SMPSLDO_INTR_OFFSET,    /* Bit 6        VXXX_SHORT              */
  67         SMPSLDO_INTR_OFFSET,    /* Bit 7        VMMC_SHORT              */
  68
  69         SMPSLDO_INTR_OFFSET,    /* Bit 8        VUSIM_SHORT             */
  70         BATDETECT_INTR_OFFSET,  /* Bit 9        BAT                     */
  71         SIMDETECT_INTR_OFFSET,  /* Bit 10       SIM                     */
  72         MMCDETECT_INTR_OFFSET,  /* Bit 11       MMC                     */
  73         RSV_INTR_OFFSET,        /* Bit 12       Reserved                */
  74         MADC_INTR_OFFSET,       /* Bit 13       GPADC_RT_EOC            */
  75         MADC_INTR_OFFSET,       /* Bit 14       GPADC_SW_EOC            */
  76         GASGAUGE_INTR_OFFSET,   /* Bit 15       CC_AUTOCAL              */
  77
  78         USBOTG_INTR_OFFSET,     /* Bit 16       ID_WKUP                 */
  79         USBOTG_INTR_OFFSET,     /* Bit 17       VBUS_WKUP               */
  80         USBOTG_INTR_OFFSET,     /* Bit 18       ID                      */
  81         USB_PRES_INTR_OFFSET,   /* Bit 19       VBUS                    */
  82         CHARGER_INTR_OFFSET,    /* Bit 20       CHRG_CTRL               */
  83         CHARGERFAULT_INTR_OFFSET,       /* Bit 21       EXT_CHRG        */
  84         CHARGERFAULT_INTR_OFFSET,       /* Bit 22       INT_CHRG        */
  85         RSV_INTR_OFFSET,        /* Bit 23       Reserved                */
  86 };
  87
  88 static int twl6032_interrupt_mapping[24] = {
  89         PWR_INTR_OFFSET,        /* Bit 0        PWRON                   */
  90         PWR_INTR_OFFSET,        /* Bit 1        RPWRON                  */
  91         PWR_INTR_OFFSET,        /* Bit 2        SYS_VLOW                */
  92         RTC_INTR_OFFSET,        /* Bit 3        RTC_ALARM               */
  93         RTC_INTR_OFFSET,        /* Bit 4        RTC_PERIOD              */
  94         HOTDIE_INTR_OFFSET,     /* Bit 5        HOT_DIE                 */
  95         SMPSLDO_INTR_OFFSET,    /* Bit 6        VXXX_SHORT              */
  96         PWR_INTR_OFFSET,        /* Bit 7        SPDURATION              */
  97
  98         PWR_INTR_OFFSET,        /* Bit 8        WATCHDOG                */
  99         BATDETECT_INTR_OFFSET,  /* Bit 9        BAT                     */
 100         SIMDETECT_INTR_OFFSET,  /* Bit 10       SIM                     */
 101         MMCDETECT_INTR_OFFSET,  /* Bit 11       MMC                     */
 102         MADC_INTR_OFFSET,       /* Bit 12       GPADC_RT_EOC            */
 103         MADC_INTR_OFFSET,       /* Bit 13       GPADC_SW_EOC            */
 104         GASGAUGE_INTR_OFFSET,   /* Bit 14       CC_EOC                  */
 105         GASGAUGE_INTR_OFFSET,   /* Bit 15       CC_AUTOCAL              */
 106
 107         USBOTG_INTR_OFFSET,     /* Bit 16       ID_WKUP                 */
 108         USBOTG_INTR_OFFSET,     /* Bit 17       VBUS_WKUP               */
 109         USBOTG_INTR_OFFSET,     /* Bit 18       ID                      */
 110         USB_PRES_INTR_OFFSET,   /* Bit 19       VBUS                    */
 111         CHARGER_INTR_OFFSET,    /* Bit 20       CHRG_CTRL               */
 112         CHARGERFAULT_INTR_OFFSET,       /* Bit 21       EXT_CHRG        */
 113         CHARGERFAULT_INTR_OFFSET,       /* Bit 22       INT_CHRG        */
 114         RSV_INTR_OFFSET,        /* Bit 23       Reserved                */
 115 };
 116
 117 /*----------------------------------------------------------------------*/
 118
 119 struct twl6030_irq {
 120         unsigned int            irq_base;
 121         int                     twl_irq;
 122         bool                    irq_wake_enabled;
 123         atomic_t                wakeirqs;
 124         struct notifier_block   pm_nb;
 125         struct irq_chip         irq_chip;
 126         struct irq_domain       *irq_domain;
 127         const int               *irq_mapping_tbl;
 128 };
 129
 130 static struct twl6030_irq *twl6030_irq;
 131
 132 static int twl6030_irq_pm_notifier(struct notifier_block *notifier,
 133                                    unsigned long pm_event, void *unused)
 134 {
 135         int chained_wakeups;
 136         struct twl6030_irq *pdata = container_of(notifier, struct twl6030_irq,
 137                                                   pm_nb);
 138
 139         switch (pm_event) {
 140         case PM_SUSPEND_PREPARE:
 141                 chained_wakeups = atomic_read(&pdata->wakeirqs);
 142
 143                 if (chained_wakeups && !pdata->irq_wake_enabled) {
 144                         if (enable_irq_wake(pdata->twl_irq))
 145                                 pr_err("twl6030 IRQ wake enable failed\n");
 146                         else
 147                                 pdata->irq_wake_enabled = true;
 148                 } else if (!chained_wakeups && pdata->irq_wake_enabled) {
 149                         disable_irq_wake(pdata->twl_irq);
 150                         pdata->irq_wake_enabled = false;
 151                 }
 152
 153                 disable_irq(pdata->twl_irq);
 154                 break;
 155
 156         case PM_POST_SUSPEND:
 157                 enable_irq(pdata->twl_irq);
 158                 break;
 159
 160         default:
 161                 break;
 162         }
 163
 164         return NOTIFY_DONE;
 165 }
 166
 167 /*
 168 * Threaded irq handler for the twl6030 interrupt.
 169 * We query the interrupt controller in the twl6030 to determine
 170 * which module is generating the interrupt request and call
 171 * handle_nested_irq for that module.
 172 */
 173 static irqreturn_t twl6030_irq_thread(int irq, void *data)
 174 {
 175         int i, ret;
 176         union {
 177                 u8 bytes[4];
 178                 __le32 int_sts;
 179         } sts;
 180         u32 int_sts; /* sts.int_sts converted to CPU endianness */
 181         struct twl6030_irq *pdata = data;
 182
 183         /* read INT_STS_A, B and C in one shot using a burst read */
 184         ret = twl_i2c_read(TWL_MODULE_PIH, sts.bytes, REG_INT_STS_A, 3);
 185         if (ret) {
 186                 pr_warn("twl6030_irq: I2C error %d reading PIH ISR\n", ret);
 187                 return IRQ_HANDLED;
 188         }
 189
 190         sts.bytes[3] = 0; /* Only 24 bits are valid*/
 191
 192         /*
 193          * Since VBUS status bit is not reliable for VBUS disconnect
 194          * use CHARGER VBUS detection status bit instead.
 195          */
 196         if (sts.bytes[2] & 0x10)
 197                 sts.bytes[2] |= 0x08;
 198
 199         int_sts = le32_to_cpu(sts.int_sts);
 200         for (i = 0; int_sts; int_sts >>= 1, i++)
 201                 if (int_sts & 0x1) {
 202                         int module_irq =
 203                                 irq_find_mapping(pdata->irq_domain,
 204                                                  pdata->irq_mapping_tbl[i]);
 205                         if (module_irq)
 206                                 handle_nested_irq(module_irq);
 207                         else
 208                                 pr_err("twl6030_irq: Unmapped PIH ISR %u detected\n",
 209                                        i);
 210                         pr_debug("twl6030_irq: PIH ISR %u, virq%u\n",
 211                                  i, module_irq);
 212                 }
 213
 214         /*
 215          * NOTE:
 216          * Simulation confirms that documentation is wrong w.r.t the
 217          * interrupt status clear operation. A single *byte* write to
 218          * any one of STS_A to STS_C register results in all three
 219          * STS registers being reset. Since it does not matter which
 220          * value is written, all three registers are cleared on a
 221          * single byte write, so we just use 0x0 to clear.
 222          */
 223         ret = twl_i2c_write_u8(TWL_MODULE_PIH, 0x00, REG_INT_STS_A);
 224         if (ret)
 225                 pr_warn("twl6030_irq: I2C error in clearing PIH ISR\n");
 226
 227         return IRQ_HANDLED;
 228 }
 229
 230 /*----------------------------------------------------------------------*/
 231
 232 static int twl6030_irq_set_wake(struct irq_data *d, unsigned int on)
 233 {
 234         struct twl6030_irq *pdata = irq_data_get_irq_chip_data(d);
 235
 236         if (on)
 237                 atomic_inc(&pdata->wakeirqs);
 238         else
 239                 atomic_dec(&pdata->wakeirqs);
 240
 241         return 0;
 242 }
 243
 244 int twl6030_interrupt_unmask(u8 bit_mask, u8 offset)
 245 {
 246         int ret;
 247         u8 unmask_value;
 248
 249         ret = twl_i2c_read_u8(TWL_MODULE_PIH, &unmask_value,
 250                         REG_INT_STS_A + offset);
 251         unmask_value &= (~(bit_mask));
 252         ret |= twl_i2c_write_u8(TWL_MODULE_PIH, unmask_value,
 253                         REG_INT_STS_A + offset); /* unmask INT_MSK_A/B/C */
 254         return ret;
 255 }
 256 EXPORT_SYMBOL(twl6030_interrupt_unmask);
 257
 258 int twl6030_interrupt_mask(u8 bit_mask, u8 offset)
 259 {
 260         int ret;
 261         u8 mask_value;
 262
 263         ret = twl_i2c_read_u8(TWL_MODULE_PIH, &mask_value,
 264                         REG_INT_STS_A + offset);
 265         mask_value |= (bit_mask);
 266         ret |= twl_i2c_write_u8(TWL_MODULE_PIH, mask_value,
 267                         REG_INT_STS_A + offset); /* mask INT_MSK_A/B/C */
 268         return ret;
 269 }
 270 EXPORT_SYMBOL(twl6030_interrupt_mask);
 271
 272 int twl6030_mmc_card_detect_config(void)
 273 {
 274         int ret;
 275         u8 reg_val = 0;
 276
 277         /* Unmasking the Card detect Interrupt line for MMC1 from Phoenix */
 278         twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
 279                                                 REG_INT_MSK_LINE_B);
 280         twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
 281                                                 REG_INT_MSK_STS_B);
 282         /*
 283          * Initially Configuring MMC_CTRL for receiving interrupts &
 284          * Card status on TWL6030 for MMC1
 285          */
 286         ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val, TWL6030_MMCCTRL);
 287         if (ret < 0) {
 288                 pr_err("twl6030: Failed to read MMCCTRL, error %d\n", ret);
 289                 return ret;
 290         }
 291         reg_val &= ~VMMC_AUTO_OFF;
 292         reg_val |= SW_FC;
 293         ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val, TWL6030_MMCCTRL);
 294         if (ret < 0) {
 295                 pr_err("twl6030: Failed to write MMCCTRL, error %d\n", ret);
 296                 return ret;
 297         }
 298
 299         /* Configuring PullUp-PullDown register */
 300         ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val,
 301                                                 TWL6030_CFG_INPUT_PUPD3);
 302         if (ret < 0) {
 303                 pr_err("twl6030: Failed to read CFG_INPUT_PUPD3, error %d\n",
 304                                                                         ret);
 305                 return ret;
 306         }
 307         reg_val &= ~(MMC_PU | MMC_PD);
 308         ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val,
 309                                                 TWL6030_CFG_INPUT_PUPD3);
 310         if (ret < 0) {
 311                 pr_err("twl6030: Failed to write CFG_INPUT_PUPD3, error %d\n",
 312                                                                         ret);
 313                 return ret;
 314         }
 315
 316         return irq_find_mapping(twl6030_irq->irq_domain,
 317                                  MMCDETECT_INTR_OFFSET);
 318 }
 319 EXPORT_SYMBOL(twl6030_mmc_card_detect_config);
 320
 321 int twl6030_mmc_card_detect(struct device *dev, int slot)
 322 {
 323         int ret = -EIO;
 324         u8 read_reg = 0;
 325         struct platform_device *pdev = to_platform_device(dev);
 326
 327         if (pdev->id) {
 328                 /* TWL6030 provide's Card detect support for
 329                  * only MMC1 controller.
 330                  */
 331                 pr_err("Unknown MMC controller %d in %s\n", pdev->id, __func__);
 332                 return ret;
 333         }
 334         /*
 335          * BIT0 of MMC_CTRL on TWL6030 provides card status for MMC1
 336          * 0 - Card not present ,1 - Card present
 337          */
 338         ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &read_reg,
 339                                                 TWL6030_MMCCTRL);
 340         if (ret >= 0)
 341                 ret = read_reg & STS_MMC;
 342         return ret;
 343 }
 344 EXPORT_SYMBOL(twl6030_mmc_card_detect);
 345
 346 static int twl6030_irq_map(struct irq_domain *d, unsigned int virq,
 347                               irq_hw_number_t hwirq)
 348 {
 349         struct twl6030_irq *pdata = d->host_data;
 350
 351         irq_set_chip_data(virq, pdata);
 352         irq_set_chip_and_handler(virq,  &pdata->irq_chip, handle_simple_irq);
 353         irq_set_nested_thread(virq, true);
 354         irq_set_parent(virq, pdata->twl_irq);
 355         irq_set_noprobe(virq);
 356
 357         return 0;
 358 }
 359
 360 static void twl6030_irq_unmap(struct irq_domain *d, unsigned int virq)
 361 {
 362         irq_set_chip_and_handler(virq, NULL, NULL);
 363         irq_set_chip_data(virq, NULL);
 364 }
 365
 366 static const struct irq_domain_ops twl6030_irq_domain_ops = {
 367         .map    = twl6030_irq_map,
 368         .unmap  = twl6030_irq_unmap,
 369         .xlate  = irq_domain_xlate_onetwocell,
 370 };
 371
 372 static const struct of_device_id twl6030_of_match[] = {
 373         {.compatible = "ti,twl6030", &twl6030_interrupt_mapping},
 374         {.compatible = "ti,twl6032", &twl6032_interrupt_mapping},
 375         { },
 376 };
 377
 378 int twl6030_init_irq(struct device *dev, int irq_num)
 379 {
 380         struct                  device_node *node = dev->of_node;
 381         int                     nr_irqs;
 382         int                     status;
 383         u8                      mask[3];
 384         const struct of_device_id *of_id;
 385
 386         of_id = of_match_device(twl6030_of_match, dev);
 387         if (!of_id || !of_id->data) {
 388                 dev_err(dev, "Unknown TWL device model\n");
 389                 return -EINVAL;
 390         }
 391
 392         nr_irqs = TWL6030_NR_IRQS;
 393
 394         twl6030_irq = devm_kzalloc(dev, sizeof(*twl6030_irq), GFP_KERNEL);
 395         if (!twl6030_irq) {
 396                 dev_err(dev, "twl6030_irq: Memory allocation failed\n");
 397                 return -ENOMEM;
 398         }
 399
 400         mask[0] = 0xFF;
 401         mask[1] = 0xFF;
 402         mask[2] = 0xFF;
 403
 404         /* mask all int lines */
 405         status = twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_MSK_LINE_A, 3);
 406         /* mask all int sts */
 407         status |= twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_MSK_STS_A, 3);
 408         /* clear INT_STS_A,B,C */
 409         status |= twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_STS_A, 3);
 410
 411         if (status < 0) {
 412                 dev_err(dev, "I2C err writing TWL_MODULE_PIH: %d\n", status);
 413                 return status;
 414         }
 415
 416         /*
 417          * install an irq handler for each of the modules;
 418          * clone dummy irq_chip since PIH can't *do* anything
 419          */
 420         twl6030_irq->irq_chip = dummy_irq_chip;
 421         twl6030_irq->irq_chip.name = "twl6030";
 422         twl6030_irq->irq_chip.irq_set_type = NULL;
 423         twl6030_irq->irq_chip.irq_set_wake = twl6030_irq_set_wake;
 424
 425         twl6030_irq->pm_nb.notifier_call = twl6030_irq_pm_notifier;
 426         atomic_set(&twl6030_irq->wakeirqs, 0);
 427         twl6030_irq->irq_mapping_tbl = of_id->data;
 428
 429         twl6030_irq->irq_domain =
 430                 irq_domain_add_linear(node, nr_irqs,
 431                                       &twl6030_irq_domain_ops, twl6030_irq);
 432         if (!twl6030_irq->irq_domain) {
 433                 dev_err(dev, "Can't add irq_domain\n");
 434                 return -ENOMEM;
 435         }
 436
 437         dev_info(dev, "PIH (irq %d) nested IRQs\n", irq_num);
 438
 439         /* install an irq handler to demultiplex the TWL6030 interrupt */
 440         status = request_threaded_irq(irq_num, NULL, twl6030_irq_thread,
 441                                       IRQF_ONESHOT, "TWL6030-PIH", twl6030_irq);
 442         if (status < 0) {
 443                 dev_err(dev, "could not claim irq %d: %d\n", irq_num, status);
 444                 goto fail_irq;
 445         }
 446
 447         twl6030_irq->twl_irq = irq_num;
 448         register_pm_notifier(&twl6030_irq->pm_nb);
 449         return 0;
 450
 451 fail_irq:
 452         irq_domain_remove(twl6030_irq->irq_domain);
 453         return status;
 454 }
 455
 456 int twl6030_exit_irq(void)
 457 {
 458         if (twl6030_irq && twl6030_irq->twl_irq) {
 459                 unregister_pm_notifier(&twl6030_irq->pm_nb);
 460                 free_irq(twl6030_irq->twl_irq, NULL);
 461                 /*
 462                  * TODO: IRQ domain and allocated nested IRQ descriptors
 463                  * should be freed somehow here. Now It can't be done, because
 464                  * child devices will not be deleted during removing of
 465                  * TWL Core driver and they will still contain allocated
 466                  * virt IRQs in their Resources tables.
 467                  * The same prevents us from using devm_request_threaded_irq()
 468                  * in this module.
 469                  */
 470         }
 471         return 0;
 472 }
 473