drivers/platform/x86/intel_bxtwc_tmu.c

   1 /*
   2  * intel_bxtwc_tmu.c - Intel BXT Whiskey Cove PMIC TMU driver
   3  *
   4  * Copyright (C) 2016 Intel Corporation. All rights reserved.
   5  *
   6  * This driver adds TMU (Time Management Unit) support for Intel BXT platform.
   7  * It enables the alarm wake-up functionality in the TMU unit of Whiskey Cove
   8  * PMIC.
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License version
  12  * 2 as published by the Free Software Foundation.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/mod_devicetable.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/platform_device.h>
  25 #include <linux/mfd/intel_soc_pmic.h>
  26
  27 #define BXTWC_TMUIRQ            0x4fb6
  28 #define BXTWC_MIRQLVL1          0x4e0e
  29 #define BXTWC_MTMUIRQ_REG       0x4fb7
  30 #define BXTWC_MIRQLVL1_MTMU     BIT(1)
  31 #define BXTWC_TMU_WK_ALRM       BIT(1)
  32 #define BXTWC_TMU_SYS_ALRM      BIT(2)
  33 #define BXTWC_TMU_ALRM_MASK     (BXTWC_TMU_WK_ALRM | BXTWC_TMU_SYS_ALRM)
  34 #define BXTWC_TMU_ALRM_IRQ      (BXTWC_TMU_WK_ALRM | BXTWC_TMU_SYS_ALRM)
  35
  36 struct wcove_tmu {
  37         int irq;
  38         struct device *dev;
  39         struct regmap *regmap;
  40 };
  41
  42 static irqreturn_t bxt_wcove_tmu_irq_handler(int irq, void *data)
  43 {
  44         struct wcove_tmu *wctmu = data;
  45         unsigned int tmu_irq;
  46
  47         /* Read TMU interrupt reg */
  48         regmap_read(wctmu->regmap, BXTWC_TMUIRQ, &tmu_irq);
  49         if (tmu_irq & BXTWC_TMU_ALRM_IRQ) {
  50                 /* clear TMU irq */
  51                 regmap_write(wctmu->regmap, BXTWC_TMUIRQ, tmu_irq);
  52                 return IRQ_HANDLED;
  53         }
  54         return IRQ_NONE;
  55 }
  56
  57 static int bxt_wcove_tmu_probe(struct platform_device *pdev)
  58 {
  59         struct intel_soc_pmic *pmic = dev_get_drvdata(pdev->dev.parent);
  60         struct regmap_irq_chip_data *regmap_irq_chip;
  61         struct wcove_tmu *wctmu;
  62         int ret, virq, irq;
  63
  64         wctmu = devm_kzalloc(&pdev->dev, sizeof(*wctmu), GFP_KERNEL);
  65         if (!wctmu)
  66                 return -ENOMEM;
  67
  68         wctmu->dev = &pdev->dev;
  69         wctmu->regmap = pmic->regmap;
  70
  71         irq = platform_get_irq(pdev, 0);
  72
  73         if (irq < 0) {
  74                 dev_err(&pdev->dev, "invalid irq %d\n", irq);
  75                 return irq;
  76         }
  77
  78         regmap_irq_chip = pmic->irq_chip_data_tmu;
  79         virq = regmap_irq_get_virq(regmap_irq_chip, irq);
  80         if (virq < 0) {
  81                 dev_err(&pdev->dev,
  82                         "failed to get virtual interrupt=%d\n", irq);
  83                 return virq;
  84         }
  85
  86         ret = devm_request_threaded_irq(&pdev->dev, virq,
  87                                         NULL, bxt_wcove_tmu_irq_handler,
  88                                         IRQF_ONESHOT, "bxt_wcove_tmu", wctmu);
  89         if (ret) {
  90                 dev_err(&pdev->dev, "request irq failed: %d,virq: %d\n",
  91                                                         ret, virq);
  92                 return ret;
  93         }
  94         wctmu->irq = virq;
  95
  96         /* Unmask TMU second level Wake & System alarm */
  97         regmap_update_bits(wctmu->regmap, BXTWC_MTMUIRQ_REG,
  98                                   BXTWC_TMU_ALRM_MASK, 0);
  99
 100         platform_set_drvdata(pdev, wctmu);
 101         return 0;
 102 }
 103
 104 static int bxt_wcove_tmu_remove(struct platform_device *pdev)
 105 {
 106         struct wcove_tmu *wctmu = platform_get_drvdata(pdev);
 107         unsigned int val;
 108
 109         /* Mask TMU interrupts */
 110         regmap_read(wctmu->regmap, BXTWC_MIRQLVL1, &val);
 111         regmap_write(wctmu->regmap, BXTWC_MIRQLVL1,
 112                         val | BXTWC_MIRQLVL1_MTMU);
 113         regmap_read(wctmu->regmap, BXTWC_MTMUIRQ_REG, &val);
 114         regmap_write(wctmu->regmap, BXTWC_MTMUIRQ_REG,
 115                         val | BXTWC_TMU_ALRM_MASK);
 116         return 0;
 117 }
 118
 119 #ifdef CONFIG_PM_SLEEP
 120 static int bxtwc_tmu_suspend(struct device *dev)
 121 {
 122         struct wcove_tmu *wctmu = dev_get_drvdata(dev);
 123
 124         enable_irq_wake(wctmu->irq);
 125         return 0;
 126 }
 127
 128 static int bxtwc_tmu_resume(struct device *dev)
 129 {
 130         struct wcove_tmu *wctmu = dev_get_drvdata(dev);
 131
 132         disable_irq_wake(wctmu->irq);
 133         return 0;
 134 }
 135 #endif
 136
 137 static SIMPLE_DEV_PM_OPS(bxtwc_tmu_pm_ops, bxtwc_tmu_suspend, bxtwc_tmu_resume);
 138
 139 static const struct platform_device_id bxt_wcove_tmu_id_table[] = {
 140         { .name = "bxt_wcove_tmu" },
 141         {},
 142 };
 143 MODULE_DEVICE_TABLE(platform, bxt_wcove_tmu_id_table);
 144
 145 static struct platform_driver bxt_wcove_tmu_driver = {
 146         .probe = bxt_wcove_tmu_probe,
 147         .remove = bxt_wcove_tmu_remove,
 148         .driver = {
 149                 .name = "bxt_wcove_tmu",
 150                 .pm     = &bxtwc_tmu_pm_ops,
 151         },
 152         .id_table = bxt_wcove_tmu_id_table,
 153 };
 154
 155 module_platform_driver(bxt_wcove_tmu_driver);
 156
 157 MODULE_LICENSE("GPL v2");
 158 MODULE_AUTHOR("Nilesh Bacchewar <nilesh.bacchewar@intel.com>");
 159 MODULE_DESCRIPTION("BXT Whiskey Cove TMU Driver");