linux/drivers/mfd/twl6030-irq.c
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   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/init.h>
  35#include <linux/export.h>
  36#include <linux/interrupt.h>
  37#include <linux/irq.h>
  38#include <linux/kthread.h>
  39#include <linux/i2c/twl.h>
  40#include <linux/platform_device.h>
  41#include <linux/suspend.h>
  42#include <linux/of.h>
  43#include <linux/irqdomain.h>
  44#include <linux/of_device.h>
  45
  46#include "twl-core.h"
  47
  48/*
  49 * TWL6030 (unlike its predecessors, which had two level interrupt handling)
  50 * three interrupt registers INT_STS_A, INT_STS_B and INT_STS_C.
  51 * It exposes status bits saying who has raised an interrupt. There are
  52 * three mask registers that corresponds to these status registers, that
  53 * enables/disables these interrupts.
  54 *
  55 * We set up IRQs starting at a platform-specified base. An interrupt map table,
  56 * specifies mapping between interrupt number and the associated module.
  57 */
  58#define TWL6030_NR_IRQS    20
  59
  60static int twl6030_interrupt_mapping[24] = {
  61        PWR_INTR_OFFSET,        /* Bit 0        PWRON                   */
  62        PWR_INTR_OFFSET,        /* Bit 1        RPWRON                  */
  63        PWR_INTR_OFFSET,        /* Bit 2        BAT_VLOW                */
  64        RTC_INTR_OFFSET,        /* Bit 3        RTC_ALARM               */
  65        RTC_INTR_OFFSET,        /* Bit 4        RTC_PERIOD              */
  66        HOTDIE_INTR_OFFSET,     /* Bit 5        HOT_DIE                 */
  67        SMPSLDO_INTR_OFFSET,    /* Bit 6        VXXX_SHORT              */
  68        SMPSLDO_INTR_OFFSET,    /* Bit 7        VMMC_SHORT              */
  69
  70        SMPSLDO_INTR_OFFSET,    /* Bit 8        VUSIM_SHORT             */
  71        BATDETECT_INTR_OFFSET,  /* Bit 9        BAT                     */
  72        SIMDETECT_INTR_OFFSET,  /* Bit 10       SIM                     */
  73        MMCDETECT_INTR_OFFSET,  /* Bit 11       MMC                     */
  74        RSV_INTR_OFFSET,        /* Bit 12       Reserved                */
  75        MADC_INTR_OFFSET,       /* Bit 13       GPADC_RT_EOC            */
  76        MADC_INTR_OFFSET,       /* Bit 14       GPADC_SW_EOC            */
  77        GASGAUGE_INTR_OFFSET,   /* Bit 15       CC_AUTOCAL              */
  78
  79        USBOTG_INTR_OFFSET,     /* Bit 16       ID_WKUP                 */
  80        USBOTG_INTR_OFFSET,     /* Bit 17       VBUS_WKUP               */
  81        USBOTG_INTR_OFFSET,     /* Bit 18       ID                      */
  82        USB_PRES_INTR_OFFSET,   /* Bit 19       VBUS                    */
  83        CHARGER_INTR_OFFSET,    /* Bit 20       CHRG_CTRL               */
  84        CHARGERFAULT_INTR_OFFSET,       /* Bit 21       EXT_CHRG        */
  85        CHARGERFAULT_INTR_OFFSET,       /* Bit 22       INT_CHRG        */
  86        RSV_INTR_OFFSET,        /* Bit 23       Reserved                */
  87};
  88
  89static int twl6032_interrupt_mapping[24] = {
  90        PWR_INTR_OFFSET,        /* Bit 0        PWRON                   */
  91        PWR_INTR_OFFSET,        /* Bit 1        RPWRON                  */
  92        PWR_INTR_OFFSET,        /* Bit 2        SYS_VLOW                */
  93        RTC_INTR_OFFSET,        /* Bit 3        RTC_ALARM               */
  94        RTC_INTR_OFFSET,        /* Bit 4        RTC_PERIOD              */
  95        HOTDIE_INTR_OFFSET,     /* Bit 5        HOT_DIE                 */
  96        SMPSLDO_INTR_OFFSET,    /* Bit 6        VXXX_SHORT              */
  97        PWR_INTR_OFFSET,        /* Bit 7        SPDURATION              */
  98
  99        PWR_INTR_OFFSET,        /* Bit 8        WATCHDOG                */
 100        BATDETECT_INTR_OFFSET,  /* Bit 9        BAT                     */
 101        SIMDETECT_INTR_OFFSET,  /* Bit 10       SIM                     */
 102        MMCDETECT_INTR_OFFSET,  /* Bit 11       MMC                     */
 103        MADC_INTR_OFFSET,       /* Bit 12       GPADC_RT_EOC            */
 104        MADC_INTR_OFFSET,       /* Bit 13       GPADC_SW_EOC            */
 105        GASGAUGE_INTR_OFFSET,   /* Bit 14       CC_EOC                  */
 106        GASGAUGE_INTR_OFFSET,   /* Bit 15       CC_AUTOCAL              */
 107
 108        USBOTG_INTR_OFFSET,     /* Bit 16       ID_WKUP                 */
 109        USBOTG_INTR_OFFSET,     /* Bit 17       VBUS_WKUP               */
 110        USBOTG_INTR_OFFSET,     /* Bit 18       ID                      */
 111        USB_PRES_INTR_OFFSET,   /* Bit 19       VBUS                    */
 112        CHARGER_INTR_OFFSET,    /* Bit 20       CHRG_CTRL               */
 113        CHARGERFAULT_INTR_OFFSET,       /* Bit 21       EXT_CHRG        */
 114        CHARGERFAULT_INTR_OFFSET,       /* Bit 22       INT_CHRG        */
 115        RSV_INTR_OFFSET,        /* Bit 23       Reserved                */
 116};
 117
 118/*----------------------------------------------------------------------*/
 119
 120struct twl6030_irq {
 121        unsigned int            irq_base;
 122        int                     twl_irq;
 123        bool                    irq_wake_enabled;
 124        atomic_t                wakeirqs;
 125        struct notifier_block   pm_nb;
 126        struct irq_chip         irq_chip;
 127        struct irq_domain       *irq_domain;
 128        const int               *irq_mapping_tbl;
 129};
 130
 131static struct twl6030_irq *twl6030_irq;
 132
 133static int twl6030_irq_pm_notifier(struct notifier_block *notifier,
 134                                   unsigned long pm_event, void *unused)
 135{
 136        int chained_wakeups;
 137        struct twl6030_irq *pdata = container_of(notifier, struct twl6030_irq,
 138                                                  pm_nb);
 139
 140        switch (pm_event) {
 141        case PM_SUSPEND_PREPARE:
 142                chained_wakeups = atomic_read(&pdata->wakeirqs);
 143
 144                if (chained_wakeups && !pdata->irq_wake_enabled) {
 145                        if (enable_irq_wake(pdata->twl_irq))
 146                                pr_err("twl6030 IRQ wake enable failed\n");
 147                        else
 148                                pdata->irq_wake_enabled = true;
 149                } else if (!chained_wakeups && pdata->irq_wake_enabled) {
 150                        disable_irq_wake(pdata->twl_irq);
 151                        pdata->irq_wake_enabled = false;
 152                }
 153
 154                disable_irq(pdata->twl_irq);
 155                break;
 156
 157        case PM_POST_SUSPEND:
 158                enable_irq(pdata->twl_irq);
 159                break;
 160
 161        default:
 162                break;
 163        }
 164
 165        return NOTIFY_DONE;
 166}
 167
 168/*
 169* Threaded irq handler for the twl6030 interrupt.
 170* We query the interrupt controller in the twl6030 to determine
 171* which module is generating the interrupt request and call
 172* handle_nested_irq for that module.
 173*/
 174static irqreturn_t twl6030_irq_thread(int irq, void *data)
 175{
 176        int i, ret;
 177        union {
 178                u8 bytes[4];
 179                u32 int_sts;
 180        } sts;
 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        for (i = 0; sts.int_sts; sts.int_sts >>= 1, i++)
 200                if (sts.int_sts & 0x1) {
 201                        int module_irq =
 202                                irq_find_mapping(pdata->irq_domain,
 203                                                 pdata->irq_mapping_tbl[i]);
 204                        if (module_irq)
 205                                handle_nested_irq(module_irq);
 206                        else
 207                                pr_err("twl6030_irq: Unmapped PIH ISR %u detected\n",
 208                                       i);
 209                        pr_debug("twl6030_irq: PIH ISR %u, virq%u\n",
 210                                 i, module_irq);
 211                }
 212
 213        /*
 214         * NOTE:
 215         * Simulation confirms that documentation is wrong w.r.t the
 216         * interrupt status clear operation. A single *byte* write to
 217         * any one of STS_A to STS_C register results in all three
 218         * STS registers being reset. Since it does not matter which
 219         * value is written, all three registers are cleared on a
 220         * single byte write, so we just use 0x0 to clear.
 221         */
 222        ret = twl_i2c_write_u8(TWL_MODULE_PIH, 0x00, REG_INT_STS_A);
 223        if (ret)
 224                pr_warn("twl6030_irq: I2C error in clearing PIH ISR\n");
 225
 226        return IRQ_HANDLED;
 227}
 228
 229/*----------------------------------------------------------------------*/
 230
 231static int twl6030_irq_set_wake(struct irq_data *d, unsigned int on)
 232{
 233        struct twl6030_irq *pdata = irq_get_chip_data(d->irq);
 234
 235        if (on)
 236                atomic_inc(&pdata->wakeirqs);
 237        else
 238                atomic_dec(&pdata->wakeirqs);
 239
 240        return 0;
 241}
 242
 243int twl6030_interrupt_unmask(u8 bit_mask, u8 offset)
 244{
 245        int ret;
 246        u8 unmask_value;
 247        ret = twl_i2c_read_u8(TWL_MODULE_PIH, &unmask_value,
 248                        REG_INT_STS_A + offset);
 249        unmask_value &= (~(bit_mask));
 250        ret |= twl_i2c_write_u8(TWL_MODULE_PIH, unmask_value,
 251                        REG_INT_STS_A + offset); /* unmask INT_MSK_A/B/C */
 252        return ret;
 253}
 254EXPORT_SYMBOL(twl6030_interrupt_unmask);
 255
 256int twl6030_interrupt_mask(u8 bit_mask, u8 offset)
 257{
 258        int ret;
 259        u8 mask_value;
 260        ret = twl_i2c_read_u8(TWL_MODULE_PIH, &mask_value,
 261                        REG_INT_STS_A + offset);
 262        mask_value |= (bit_mask);
 263        ret |= twl_i2c_write_u8(TWL_MODULE_PIH, mask_value,
 264                        REG_INT_STS_A + offset); /* mask INT_MSK_A/B/C */
 265        return ret;
 266}
 267EXPORT_SYMBOL(twl6030_interrupt_mask);
 268
 269int twl6030_mmc_card_detect_config(void)
 270{
 271        int ret;
 272        u8 reg_val = 0;
 273
 274        /* Unmasking the Card detect Interrupt line for MMC1 from Phoenix */
 275        twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
 276                                                REG_INT_MSK_LINE_B);
 277        twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
 278                                                REG_INT_MSK_STS_B);
 279        /*
 280         * Initially Configuring MMC_CTRL for receiving interrupts &
 281         * Card status on TWL6030 for MMC1
 282         */
 283        ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val, TWL6030_MMCCTRL);
 284        if (ret < 0) {
 285                pr_err("twl6030: Failed to read MMCCTRL, error %d\n", ret);
 286                return ret;
 287        }
 288        reg_val &= ~VMMC_AUTO_OFF;
 289        reg_val |= SW_FC;
 290        ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val, TWL6030_MMCCTRL);
 291        if (ret < 0) {
 292                pr_err("twl6030: Failed to write MMCCTRL, error %d\n", ret);
 293                return ret;
 294        }
 295
 296        /* Configuring PullUp-PullDown register */
 297        ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val,
 298                                                TWL6030_CFG_INPUT_PUPD3);
 299        if (ret < 0) {
 300                pr_err("twl6030: Failed to read CFG_INPUT_PUPD3, error %d\n",
 301                                                                        ret);
 302                return ret;
 303        }
 304        reg_val &= ~(MMC_PU | MMC_PD);
 305        ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val,
 306                                                TWL6030_CFG_INPUT_PUPD3);
 307        if (ret < 0) {
 308                pr_err("twl6030: Failed to write CFG_INPUT_PUPD3, error %d\n",
 309                                                                        ret);
 310                return ret;
 311        }
 312
 313        return irq_find_mapping(twl6030_irq->irq_domain,
 314                                 MMCDETECT_INTR_OFFSET);
 315}
 316EXPORT_SYMBOL(twl6030_mmc_card_detect_config);
 317
 318int twl6030_mmc_card_detect(struct device *dev, int slot)
 319{
 320        int ret = -EIO;
 321        u8 read_reg = 0;
 322        struct platform_device *pdev = to_platform_device(dev);
 323
 324        if (pdev->id) {
 325                /* TWL6030 provide's Card detect support for
 326                 * only MMC1 controller.
 327                 */
 328                pr_err("Unknown MMC controller %d in %s\n", pdev->id, __func__);
 329                return ret;
 330        }
 331        /*
 332         * BIT0 of MMC_CTRL on TWL6030 provides card status for MMC1
 333         * 0 - Card not present ,1 - Card present
 334         */
 335        ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &read_reg,
 336                                                TWL6030_MMCCTRL);
 337        if (ret >= 0)
 338                ret = read_reg & STS_MMC;
 339        return ret;
 340}
 341EXPORT_SYMBOL(twl6030_mmc_card_detect);
 342
 343static int twl6030_irq_map(struct irq_domain *d, unsigned int virq,
 344                              irq_hw_number_t hwirq)
 345{
 346        struct twl6030_irq *pdata = d->host_data;
 347
 348        irq_set_chip_data(virq, pdata);
 349        irq_set_chip_and_handler(virq,  &pdata->irq_chip, handle_simple_irq);
 350        irq_set_nested_thread(virq, true);
 351        irq_set_parent(virq, pdata->twl_irq);
 352
 353#ifdef CONFIG_ARM
 354        /*
 355         * ARM requires an extra step to clear IRQ_NOREQUEST, which it
 356         * sets on behalf of every irq_chip.  Also sets IRQ_NOPROBE.
 357         */
 358        set_irq_flags(virq, IRQF_VALID);
 359#else
 360        /* same effect on other architectures */
 361        irq_set_noprobe(virq);
 362#endif
 363
 364        return 0;
 365}
 366
 367static void twl6030_irq_unmap(struct irq_domain *d, unsigned int virq)
 368{
 369#ifdef CONFIG_ARM
 370        set_irq_flags(virq, 0);
 371#endif
 372        irq_set_chip_and_handler(virq, NULL, NULL);
 373        irq_set_chip_data(virq, NULL);
 374}
 375
 376static struct irq_domain_ops twl6030_irq_domain_ops = {
 377        .map    = twl6030_irq_map,
 378        .unmap  = twl6030_irq_unmap,
 379        .xlate  = irq_domain_xlate_onetwocell,
 380};
 381
 382static const struct of_device_id twl6030_of_match[] = {
 383        {.compatible = "ti,twl6030", &twl6030_interrupt_mapping},
 384        {.compatible = "ti,twl6032", &twl6032_interrupt_mapping},
 385        { },
 386};
 387
 388int twl6030_init_irq(struct device *dev, int irq_num)
 389{
 390        struct                  device_node *node = dev->of_node;
 391        int                     nr_irqs;
 392        int                     status;
 393        u8                      mask[3];
 394        const struct of_device_id *of_id;
 395
 396        of_id = of_match_device(twl6030_of_match, dev);
 397        if (!of_id || !of_id->data) {
 398                dev_err(dev, "Unknown TWL device model\n");
 399                return -EINVAL;
 400        }
 401
 402        nr_irqs = TWL6030_NR_IRQS;
 403
 404        twl6030_irq = devm_kzalloc(dev, sizeof(*twl6030_irq), GFP_KERNEL);
 405        if (!twl6030_irq) {
 406                dev_err(dev, "twl6030_irq: Memory allocation failed\n");
 407                return -ENOMEM;
 408        }
 409
 410        mask[0] = 0xFF;
 411        mask[1] = 0xFF;
 412        mask[2] = 0xFF;
 413
 414        /* mask all int lines */
 415        status = twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_MSK_LINE_A, 3);
 416        /* mask all int sts */
 417        status |= twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_MSK_STS_A, 3);
 418        /* clear INT_STS_A,B,C */
 419        status |= twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_STS_A, 3);
 420
 421        if (status < 0) {
 422                dev_err(dev, "I2C err writing TWL_MODULE_PIH: %d\n", status);
 423                return status;
 424        }
 425
 426        /*
 427         * install an irq handler for each of the modules;
 428         * clone dummy irq_chip since PIH can't *do* anything
 429         */
 430        twl6030_irq->irq_chip = dummy_irq_chip;
 431        twl6030_irq->irq_chip.name = "twl6030";
 432        twl6030_irq->irq_chip.irq_set_type = NULL;
 433        twl6030_irq->irq_chip.irq_set_wake = twl6030_irq_set_wake;
 434
 435        twl6030_irq->pm_nb.notifier_call = twl6030_irq_pm_notifier;
 436        atomic_set(&twl6030_irq->wakeirqs, 0);
 437        twl6030_irq->irq_mapping_tbl = of_id->data;
 438
 439        twl6030_irq->irq_domain =
 440                irq_domain_add_linear(node, nr_irqs,
 441                                      &twl6030_irq_domain_ops, twl6030_irq);
 442        if (!twl6030_irq->irq_domain) {
 443                dev_err(dev, "Can't add irq_domain\n");
 444                return -ENOMEM;
 445        }
 446
 447        dev_info(dev, "PIH (irq %d) nested IRQs\n", irq_num);
 448
 449        /* install an irq handler to demultiplex the TWL6030 interrupt */
 450        status = request_threaded_irq(irq_num, NULL, twl6030_irq_thread,
 451                                      IRQF_ONESHOT, "TWL6030-PIH", twl6030_irq);
 452        if (status < 0) {
 453                dev_err(dev, "could not claim irq %d: %d\n", irq_num, status);
 454                goto fail_irq;
 455        }
 456
 457        twl6030_irq->twl_irq = irq_num;
 458        register_pm_notifier(&twl6030_irq->pm_nb);
 459        return 0;
 460
 461fail_irq:
 462        irq_domain_remove(twl6030_irq->irq_domain);
 463        return status;
 464}
 465
 466int twl6030_exit_irq(void)
 467{
 468        if (twl6030_irq && twl6030_irq->twl_irq) {
 469                unregister_pm_notifier(&twl6030_irq->pm_nb);
 470                free_irq(twl6030_irq->twl_irq, NULL);
 471                /*
 472                 * TODO: IRQ domain and allocated nested IRQ descriptors
 473                 * should be freed somehow here. Now It can't be done, because
 474                 * child devices will not be deleted during removing of
 475                 * TWL Core driver and they will still contain allocated
 476                 * virt IRQs in their Resources tables.
 477                 * The same prevents us from using devm_request_threaded_irq()
 478                 * in this module.
 479                 */
 480        }
 481        return 0;
 482}
 483
 484
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