linux/drivers/mfd/twl6030-irq.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * twl6030-irq.c - TWL6030 irq support
   4 *
   5 * Copyright (C) 2005-2009 Texas Instruments, Inc.
   6 *
   7 * Modifications to defer interrupt handling to a kernel thread:
   8 * Copyright (C) 2006 MontaVista Software, Inc.
   9 *
  10 * Based on tlv320aic23.c:
  11 * Copyright (c) by Kai Svahn <kai.svahn@nokia.com>
  12 *
  13 * Code cleanup and modifications to IRQ handler.
  14 * by syed khasim <x0khasim@ti.com>
  15 *
  16 * TWL6030 specific code and IRQ handling changes by
  17 * Jagadeesh Bhaskar Pakaravoor <j-pakaravoor@ti.com>
  18 * Balaji T K <balajitk@ti.com>
  19 */
  20
  21#include <linux/export.h>
  22#include <linux/interrupt.h>
  23#include <linux/irq.h>
  24#include <linux/kthread.h>
  25#include <linux/mfd/twl.h>
  26#include <linux/platform_device.h>
  27#include <linux/suspend.h>
  28#include <linux/of.h>
  29#include <linux/irqdomain.h>
  30#include <linux/of_device.h>
  31
  32#include "twl-core.h"
  33
  34/*
  35 * TWL6030 (unlike its predecessors, which had two level interrupt handling)
  36 * three interrupt registers INT_STS_A, INT_STS_B and INT_STS_C.
  37 * It exposes status bits saying who has raised an interrupt. There are
  38 * three mask registers that corresponds to these status registers, that
  39 * enables/disables these interrupts.
  40 *
  41 * We set up IRQs starting at a platform-specified base. An interrupt map table,
  42 * specifies mapping between interrupt number and the associated module.
  43 */
  44#define TWL6030_NR_IRQS    20
  45
  46static int twl6030_interrupt_mapping[24] = {
  47        PWR_INTR_OFFSET,        /* Bit 0        PWRON                   */
  48        PWR_INTR_OFFSET,        /* Bit 1        RPWRON                  */
  49        PWR_INTR_OFFSET,        /* Bit 2        BAT_VLOW                */
  50        RTC_INTR_OFFSET,        /* Bit 3        RTC_ALARM               */
  51        RTC_INTR_OFFSET,        /* Bit 4        RTC_PERIOD              */
  52        HOTDIE_INTR_OFFSET,     /* Bit 5        HOT_DIE                 */
  53        SMPSLDO_INTR_OFFSET,    /* Bit 6        VXXX_SHORT              */
  54        SMPSLDO_INTR_OFFSET,    /* Bit 7        VMMC_SHORT              */
  55
  56        SMPSLDO_INTR_OFFSET,    /* Bit 8        VUSIM_SHORT             */
  57        BATDETECT_INTR_OFFSET,  /* Bit 9        BAT                     */
  58        SIMDETECT_INTR_OFFSET,  /* Bit 10       SIM                     */
  59        MMCDETECT_INTR_OFFSET,  /* Bit 11       MMC                     */
  60        RSV_INTR_OFFSET,        /* Bit 12       Reserved                */
  61        MADC_INTR_OFFSET,       /* Bit 13       GPADC_RT_EOC            */
  62        MADC_INTR_OFFSET,       /* Bit 14       GPADC_SW_EOC            */
  63        GASGAUGE_INTR_OFFSET,   /* Bit 15       CC_AUTOCAL              */
  64
  65        USBOTG_INTR_OFFSET,     /* Bit 16       ID_WKUP                 */
  66        USBOTG_INTR_OFFSET,     /* Bit 17       VBUS_WKUP               */
  67        USBOTG_INTR_OFFSET,     /* Bit 18       ID                      */
  68        USB_PRES_INTR_OFFSET,   /* Bit 19       VBUS                    */
  69        CHARGER_INTR_OFFSET,    /* Bit 20       CHRG_CTRL               */
  70        CHARGERFAULT_INTR_OFFSET,       /* Bit 21       EXT_CHRG        */
  71        CHARGERFAULT_INTR_OFFSET,       /* Bit 22       INT_CHRG        */
  72        RSV_INTR_OFFSET,        /* Bit 23       Reserved                */
  73};
  74
  75static int twl6032_interrupt_mapping[24] = {
  76        PWR_INTR_OFFSET,        /* Bit 0        PWRON                   */
  77        PWR_INTR_OFFSET,        /* Bit 1        RPWRON                  */
  78        PWR_INTR_OFFSET,        /* Bit 2        SYS_VLOW                */
  79        RTC_INTR_OFFSET,        /* Bit 3        RTC_ALARM               */
  80        RTC_INTR_OFFSET,        /* Bit 4        RTC_PERIOD              */
  81        HOTDIE_INTR_OFFSET,     /* Bit 5        HOT_DIE                 */
  82        SMPSLDO_INTR_OFFSET,    /* Bit 6        VXXX_SHORT              */
  83        PWR_INTR_OFFSET,        /* Bit 7        SPDURATION              */
  84
  85        PWR_INTR_OFFSET,        /* Bit 8        WATCHDOG                */
  86        BATDETECT_INTR_OFFSET,  /* Bit 9        BAT                     */
  87        SIMDETECT_INTR_OFFSET,  /* Bit 10       SIM                     */
  88        MMCDETECT_INTR_OFFSET,  /* Bit 11       MMC                     */
  89        MADC_INTR_OFFSET,       /* Bit 12       GPADC_RT_EOC            */
  90        MADC_INTR_OFFSET,       /* Bit 13       GPADC_SW_EOC            */
  91        GASGAUGE_INTR_OFFSET,   /* Bit 14       CC_EOC                  */
  92        GASGAUGE_INTR_OFFSET,   /* Bit 15       CC_AUTOCAL              */
  93
  94        USBOTG_INTR_OFFSET,     /* Bit 16       ID_WKUP                 */
  95        USBOTG_INTR_OFFSET,     /* Bit 17       VBUS_WKUP               */
  96        USBOTG_INTR_OFFSET,     /* Bit 18       ID                      */
  97        USB_PRES_INTR_OFFSET,   /* Bit 19       VBUS                    */
  98        CHARGER_INTR_OFFSET,    /* Bit 20       CHRG_CTRL               */
  99        CHARGERFAULT_INTR_OFFSET,       /* Bit 21       EXT_CHRG        */
 100        CHARGERFAULT_INTR_OFFSET,       /* Bit 22       INT_CHRG        */
 101        RSV_INTR_OFFSET,        /* Bit 23       Reserved                */
 102};
 103
 104/*----------------------------------------------------------------------*/
 105
 106struct twl6030_irq {
 107        unsigned int            irq_base;
 108        int                     twl_irq;
 109        bool                    irq_wake_enabled;
 110        atomic_t                wakeirqs;
 111        struct notifier_block   pm_nb;
 112        struct irq_chip         irq_chip;
 113        struct irq_domain       *irq_domain;
 114        const int               *irq_mapping_tbl;
 115};
 116
 117static struct twl6030_irq *twl6030_irq;
 118
 119static int twl6030_irq_pm_notifier(struct notifier_block *notifier,
 120                                   unsigned long pm_event, void *unused)
 121{
 122        int chained_wakeups;
 123        struct twl6030_irq *pdata = container_of(notifier, struct twl6030_irq,
 124                                                  pm_nb);
 125
 126        switch (pm_event) {
 127        case PM_SUSPEND_PREPARE:
 128                chained_wakeups = atomic_read(&pdata->wakeirqs);
 129
 130                if (chained_wakeups && !pdata->irq_wake_enabled) {
 131                        if (enable_irq_wake(pdata->twl_irq))
 132                                pr_err("twl6030 IRQ wake enable failed\n");
 133                        else
 134                                pdata->irq_wake_enabled = true;
 135                } else if (!chained_wakeups && pdata->irq_wake_enabled) {
 136                        disable_irq_wake(pdata->twl_irq);
 137                        pdata->irq_wake_enabled = false;
 138                }
 139
 140                disable_irq(pdata->twl_irq);
 141                break;
 142
 143        case PM_POST_SUSPEND:
 144                enable_irq(pdata->twl_irq);
 145                break;
 146
 147        default:
 148                break;
 149        }
 150
 151        return NOTIFY_DONE;
 152}
 153
 154/*
 155* Threaded irq handler for the twl6030 interrupt.
 156* We query the interrupt controller in the twl6030 to determine
 157* which module is generating the interrupt request and call
 158* handle_nested_irq for that module.
 159*/
 160static irqreturn_t twl6030_irq_thread(int irq, void *data)
 161{
 162        int i, ret;
 163        union {
 164                u8 bytes[4];
 165                __le32 int_sts;
 166        } sts;
 167        u32 int_sts; /* sts.int_sts converted to CPU endianness */
 168        struct twl6030_irq *pdata = data;
 169
 170        /* read INT_STS_A, B and C in one shot using a burst read */
 171        ret = twl_i2c_read(TWL_MODULE_PIH, sts.bytes, REG_INT_STS_A, 3);
 172        if (ret) {
 173                pr_warn("twl6030_irq: I2C error %d reading PIH ISR\n", ret);
 174                return IRQ_HANDLED;
 175        }
 176
 177        sts.bytes[3] = 0; /* Only 24 bits are valid*/
 178
 179        /*
 180         * Since VBUS status bit is not reliable for VBUS disconnect
 181         * use CHARGER VBUS detection status bit instead.
 182         */
 183        if (sts.bytes[2] & 0x10)
 184                sts.bytes[2] |= 0x08;
 185
 186        int_sts = le32_to_cpu(sts.int_sts);
 187        for (i = 0; int_sts; int_sts >>= 1, i++)
 188                if (int_sts & 0x1) {
 189                        int module_irq =
 190                                irq_find_mapping(pdata->irq_domain,
 191                                                 pdata->irq_mapping_tbl[i]);
 192                        if (module_irq)
 193                                handle_nested_irq(module_irq);
 194                        else
 195                                pr_err("twl6030_irq: Unmapped PIH ISR %u detected\n",
 196                                       i);
 197                        pr_debug("twl6030_irq: PIH ISR %u, virq%u\n",
 198                                 i, module_irq);
 199                }
 200
 201        /*
 202         * NOTE:
 203         * Simulation confirms that documentation is wrong w.r.t the
 204         * interrupt status clear operation. A single *byte* write to
 205         * any one of STS_A to STS_C register results in all three
 206         * STS registers being reset. Since it does not matter which
 207         * value is written, all three registers are cleared on a
 208         * single byte write, so we just use 0x0 to clear.
 209         */
 210        ret = twl_i2c_write_u8(TWL_MODULE_PIH, 0x00, REG_INT_STS_A);
 211        if (ret)
 212                pr_warn("twl6030_irq: I2C error in clearing PIH ISR\n");
 213
 214        return IRQ_HANDLED;
 215}
 216
 217/*----------------------------------------------------------------------*/
 218
 219static int twl6030_irq_set_wake(struct irq_data *d, unsigned int on)
 220{
 221        struct twl6030_irq *pdata = irq_data_get_irq_chip_data(d);
 222
 223        if (on)
 224                atomic_inc(&pdata->wakeirqs);
 225        else
 226                atomic_dec(&pdata->wakeirqs);
 227
 228        return 0;
 229}
 230
 231int twl6030_interrupt_unmask(u8 bit_mask, u8 offset)
 232{
 233        int ret;
 234        u8 unmask_value;
 235
 236        ret = twl_i2c_read_u8(TWL_MODULE_PIH, &unmask_value,
 237                        REG_INT_STS_A + offset);
 238        unmask_value &= (~(bit_mask));
 239        ret |= twl_i2c_write_u8(TWL_MODULE_PIH, unmask_value,
 240                        REG_INT_STS_A + offset); /* unmask INT_MSK_A/B/C */
 241        return ret;
 242}
 243EXPORT_SYMBOL(twl6030_interrupt_unmask);
 244
 245int twl6030_interrupt_mask(u8 bit_mask, u8 offset)
 246{
 247        int ret;
 248        u8 mask_value;
 249
 250        ret = twl_i2c_read_u8(TWL_MODULE_PIH, &mask_value,
 251                        REG_INT_STS_A + offset);
 252        mask_value |= (bit_mask);
 253        ret |= twl_i2c_write_u8(TWL_MODULE_PIH, mask_value,
 254                        REG_INT_STS_A + offset); /* mask INT_MSK_A/B/C */
 255        return ret;
 256}
 257EXPORT_SYMBOL(twl6030_interrupt_mask);
 258
 259int twl6030_mmc_card_detect_config(void)
 260{
 261        int ret;
 262        u8 reg_val = 0;
 263
 264        /* Unmasking the Card detect Interrupt line for MMC1 from Phoenix */
 265        twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
 266                                                REG_INT_MSK_LINE_B);
 267        twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
 268                                                REG_INT_MSK_STS_B);
 269        /*
 270         * Initially Configuring MMC_CTRL for receiving interrupts &
 271         * Card status on TWL6030 for MMC1
 272         */
 273        ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val, TWL6030_MMCCTRL);
 274        if (ret < 0) {
 275                pr_err("twl6030: Failed to read MMCCTRL, error %d\n", ret);
 276                return ret;
 277        }
 278        reg_val &= ~VMMC_AUTO_OFF;
 279        reg_val |= SW_FC;
 280        ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val, TWL6030_MMCCTRL);
 281        if (ret < 0) {
 282                pr_err("twl6030: Failed to write MMCCTRL, error %d\n", ret);
 283                return ret;
 284        }
 285
 286        /* Configuring PullUp-PullDown register */
 287        ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val,
 288                                                TWL6030_CFG_INPUT_PUPD3);
 289        if (ret < 0) {
 290                pr_err("twl6030: Failed to read CFG_INPUT_PUPD3, error %d\n",
 291                                                                        ret);
 292                return ret;
 293        }
 294        reg_val &= ~(MMC_PU | MMC_PD);
 295        ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val,
 296                                                TWL6030_CFG_INPUT_PUPD3);
 297        if (ret < 0) {
 298                pr_err("twl6030: Failed to write CFG_INPUT_PUPD3, error %d\n",
 299                                                                        ret);
 300                return ret;
 301        }
 302
 303        return irq_find_mapping(twl6030_irq->irq_domain,
 304                                 MMCDETECT_INTR_OFFSET);
 305}
 306EXPORT_SYMBOL(twl6030_mmc_card_detect_config);
 307
 308int twl6030_mmc_card_detect(struct device *dev, int slot)
 309{
 310        int ret = -EIO;
 311        u8 read_reg = 0;
 312        struct platform_device *pdev = to_platform_device(dev);
 313
 314        if (pdev->id) {
 315                /* TWL6030 provide's Card detect support for
 316                 * only MMC1 controller.
 317                 */
 318                pr_err("Unknown MMC controller %d in %s\n", pdev->id, __func__);
 319                return ret;
 320        }
 321        /*
 322         * BIT0 of MMC_CTRL on TWL6030 provides card status for MMC1
 323         * 0 - Card not present ,1 - Card present
 324         */
 325        ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &read_reg,
 326                                                TWL6030_MMCCTRL);
 327        if (ret >= 0)
 328                ret = read_reg & STS_MMC;
 329        return ret;
 330}
 331EXPORT_SYMBOL(twl6030_mmc_card_detect);
 332
 333static int twl6030_irq_map(struct irq_domain *d, unsigned int virq,
 334                              irq_hw_number_t hwirq)
 335{
 336        struct twl6030_irq *pdata = d->host_data;
 337
 338        irq_set_chip_data(virq, pdata);
 339        irq_set_chip_and_handler(virq,  &pdata->irq_chip, handle_simple_irq);
 340        irq_set_nested_thread(virq, true);
 341        irq_set_parent(virq, pdata->twl_irq);
 342        irq_set_noprobe(virq);
 343
 344        return 0;
 345}
 346
 347static void twl6030_irq_unmap(struct irq_domain *d, unsigned int virq)
 348{
 349        irq_set_chip_and_handler(virq, NULL, NULL);
 350        irq_set_chip_data(virq, NULL);
 351}
 352
 353static const struct irq_domain_ops twl6030_irq_domain_ops = {
 354        .map    = twl6030_irq_map,
 355        .unmap  = twl6030_irq_unmap,
 356        .xlate  = irq_domain_xlate_onetwocell,
 357};
 358
 359static const struct of_device_id twl6030_of_match[] __maybe_unused = {
 360        {.compatible = "ti,twl6030", &twl6030_interrupt_mapping},
 361        {.compatible = "ti,twl6032", &twl6032_interrupt_mapping},
 362        { },
 363};
 364
 365int twl6030_init_irq(struct device *dev, int irq_num)
 366{
 367        struct                  device_node *node = dev->of_node;
 368        int                     nr_irqs;
 369        int                     status;
 370        u8                      mask[3];
 371        const struct of_device_id *of_id;
 372
 373        of_id = of_match_device(twl6030_of_match, dev);
 374        if (!of_id || !of_id->data) {
 375                dev_err(dev, "Unknown TWL device model\n");
 376                return -EINVAL;
 377        }
 378
 379        nr_irqs = TWL6030_NR_IRQS;
 380
 381        twl6030_irq = devm_kzalloc(dev, sizeof(*twl6030_irq), GFP_KERNEL);
 382        if (!twl6030_irq)
 383                return -ENOMEM;
 384
 385        mask[0] = 0xFF;
 386        mask[1] = 0xFF;
 387        mask[2] = 0xFF;
 388
 389        /* mask all int lines */
 390        status = twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_MSK_LINE_A, 3);
 391        /* mask all int sts */
 392        status |= twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_MSK_STS_A, 3);
 393        /* clear INT_STS_A,B,C */
 394        status |= twl_i2c_write(TWL_MODULE_PIH, &mask[0], REG_INT_STS_A, 3);
 395
 396        if (status < 0) {
 397                dev_err(dev, "I2C err writing TWL_MODULE_PIH: %d\n", status);
 398                return status;
 399        }
 400
 401        /*
 402         * install an irq handler for each of the modules;
 403         * clone dummy irq_chip since PIH can't *do* anything
 404         */
 405        twl6030_irq->irq_chip = dummy_irq_chip;
 406        twl6030_irq->irq_chip.name = "twl6030";
 407        twl6030_irq->irq_chip.irq_set_type = NULL;
 408        twl6030_irq->irq_chip.irq_set_wake = twl6030_irq_set_wake;
 409
 410        twl6030_irq->pm_nb.notifier_call = twl6030_irq_pm_notifier;
 411        atomic_set(&twl6030_irq->wakeirqs, 0);
 412        twl6030_irq->irq_mapping_tbl = of_id->data;
 413
 414        twl6030_irq->irq_domain =
 415                irq_domain_add_linear(node, nr_irqs,
 416                                      &twl6030_irq_domain_ops, twl6030_irq);
 417        if (!twl6030_irq->irq_domain) {
 418                dev_err(dev, "Can't add irq_domain\n");
 419                return -ENOMEM;
 420        }
 421
 422        dev_info(dev, "PIH (irq %d) nested IRQs\n", irq_num);
 423
 424        /* install an irq handler to demultiplex the TWL6030 interrupt */
 425        status = request_threaded_irq(irq_num, NULL, twl6030_irq_thread,
 426                                      IRQF_ONESHOT, "TWL6030-PIH", twl6030_irq);
 427        if (status < 0) {
 428                dev_err(dev, "could not claim irq %d: %d\n", irq_num, status);
 429                goto fail_irq;
 430        }
 431
 432        twl6030_irq->twl_irq = irq_num;
 433        register_pm_notifier(&twl6030_irq->pm_nb);
 434        return 0;
 435
 436fail_irq:
 437        irq_domain_remove(twl6030_irq->irq_domain);
 438        return status;
 439}
 440
 441int twl6030_exit_irq(void)
 442{
 443        if (twl6030_irq && twl6030_irq->twl_irq) {
 444                unregister_pm_notifier(&twl6030_irq->pm_nb);
 445                free_irq(twl6030_irq->twl_irq, NULL);
 446                /*
 447                 * TODO: IRQ domain and allocated nested IRQ descriptors
 448                 * should be freed somehow here. Now It can't be done, because
 449                 * child devices will not be deleted during removing of
 450                 * TWL Core driver and they will still contain allocated
 451                 * virt IRQs in their Resources tables.
 452                 * The same prevents us from using devm_request_threaded_irq()
 453                 * in this module.
 454                 */
 455        }
 456        return 0;
 457}
 458
 459