drivers/platform/x86/intel/bxtwc_tmu.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Intel BXT Whiskey Cove PMIC TMU driver
   4  *
   5  * Copyright (C) 2016 Intel Corporation. All rights reserved.
   6  *
   7  * This driver adds TMU (Time Management Unit) support for Intel BXT platform.
   8  * It enables the alarm wake-up functionality in the TMU unit of Whiskey Cove
   9  * PMIC.
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/mod_devicetable.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/mfd/intel_soc_pmic.h>
  17
  18 #define BXTWC_TMUIRQ            0x4fb6
  19 #define BXTWC_MIRQLVL1          0x4e0e
  20 #define BXTWC_MTMUIRQ_REG       0x4fb7
  21 #define BXTWC_MIRQLVL1_MTMU     BIT(1)
  22 #define BXTWC_TMU_WK_ALRM       BIT(1)
  23 #define BXTWC_TMU_SYS_ALRM      BIT(2)
  24 #define BXTWC_TMU_ALRM_MASK     (BXTWC_TMU_WK_ALRM | BXTWC_TMU_SYS_ALRM)
  25 #define BXTWC_TMU_ALRM_IRQ      (BXTWC_TMU_WK_ALRM | BXTWC_TMU_SYS_ALRM)
  26
  27 struct wcove_tmu {
  28         int irq;
  29         struct device *dev;
  30         struct regmap *regmap;
  31 };
  32
  33 static irqreturn_t bxt_wcove_tmu_irq_handler(int irq, void *data)
  34 {
  35         struct wcove_tmu *wctmu = data;
  36         unsigned int tmu_irq;
  37
  38         /* Read TMU interrupt reg */
  39         regmap_read(wctmu->regmap, BXTWC_TMUIRQ, &tmu_irq);
  40         if (tmu_irq & BXTWC_TMU_ALRM_IRQ) {
  41                 /* clear TMU irq */
  42                 regmap_write(wctmu->regmap, BXTWC_TMUIRQ, tmu_irq);
  43                 return IRQ_HANDLED;
  44         }
  45         return IRQ_NONE;
  46 }
  47
  48 static int bxt_wcove_tmu_probe(struct platform_device *pdev)
  49 {
  50         struct intel_soc_pmic *pmic = dev_get_drvdata(pdev->dev.parent);
  51         struct wcove_tmu *wctmu;
  52         int ret;
  53
  54         wctmu = devm_kzalloc(&pdev->dev, sizeof(*wctmu), GFP_KERNEL);
  55         if (!wctmu)
  56                 return -ENOMEM;
  57
  58         wctmu->dev = &pdev->dev;
  59         wctmu->regmap = pmic->regmap;
  60
  61         wctmu->irq = platform_get_irq(pdev, 0);
  62         if (wctmu->irq < 0)
  63                 return wctmu->irq;
  64
  65         ret = devm_request_threaded_irq(&pdev->dev, wctmu->irq,
  66                                         NULL, bxt_wcove_tmu_irq_handler,
  67                                         IRQF_ONESHOT, "bxt_wcove_tmu", wctmu);
  68         if (ret) {
  69                 dev_err(&pdev->dev, "request irq failed: %d,virq: %d\n",
  70                         ret, wctmu->irq);
  71                 return ret;
  72         }
  73
  74         /* Unmask TMU second level Wake & System alarm */
  75         regmap_update_bits(wctmu->regmap, BXTWC_MTMUIRQ_REG,
  76                                   BXTWC_TMU_ALRM_MASK, 0);
  77
  78         platform_set_drvdata(pdev, wctmu);
  79         return 0;
  80 }
  81
  82 static void bxt_wcove_tmu_remove(struct platform_device *pdev)
  83 {
  84         struct wcove_tmu *wctmu = platform_get_drvdata(pdev);
  85         unsigned int val;
  86
  87         /* Mask TMU interrupts */
  88         regmap_read(wctmu->regmap, BXTWC_MIRQLVL1, &val);
  89         regmap_write(wctmu->regmap, BXTWC_MIRQLVL1,
  90                         val | BXTWC_MIRQLVL1_MTMU);
  91         regmap_read(wctmu->regmap, BXTWC_MTMUIRQ_REG, &val);
  92         regmap_write(wctmu->regmap, BXTWC_MTMUIRQ_REG,
  93                         val | BXTWC_TMU_ALRM_MASK);
  94 }
  95
  96 #ifdef CONFIG_PM_SLEEP
  97 static int bxtwc_tmu_suspend(struct device *dev)
  98 {
  99         struct wcove_tmu *wctmu = dev_get_drvdata(dev);
 100
 101         enable_irq_wake(wctmu->irq);
 102         return 0;
 103 }
 104
 105 static int bxtwc_tmu_resume(struct device *dev)
 106 {
 107         struct wcove_tmu *wctmu = dev_get_drvdata(dev);
 108
 109         disable_irq_wake(wctmu->irq);
 110         return 0;
 111 }
 112 #endif
 113
 114 static SIMPLE_DEV_PM_OPS(bxtwc_tmu_pm_ops, bxtwc_tmu_suspend, bxtwc_tmu_resume);
 115
 116 static const struct platform_device_id bxt_wcove_tmu_id_table[] = {
 117         { .name = "bxt_wcove_tmu" },
 118         {},
 119 };
 120 MODULE_DEVICE_TABLE(platform, bxt_wcove_tmu_id_table);
 121
 122 static struct platform_driver bxt_wcove_tmu_driver = {
 123         .probe = bxt_wcove_tmu_probe,
 124         .remove = bxt_wcove_tmu_remove,
 125         .driver = {
 126                 .name = "bxt_wcove_tmu",
 127                 .pm     = &bxtwc_tmu_pm_ops,
 128         },
 129         .id_table = bxt_wcove_tmu_id_table,
 130 };
 131
 132 module_platform_driver(bxt_wcove_tmu_driver);
 133
 134 MODULE_LICENSE("GPL v2");
 135 MODULE_AUTHOR("Nilesh Bacchewar <nilesh.bacchewar@intel.com>");
 136 MODULE_DESCRIPTION("BXT Whiskey Cove TMU Driver");