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
 27struct wcove_tmu {
 28	int irq;
 29	struct device *dev;
 30	struct regmap *regmap;
 31};
 32
 33static 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
 48static 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
 82static 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
 97static 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
105static 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
114static SIMPLE_DEV_PM_OPS(bxtwc_tmu_pm_ops, bxtwc_tmu_suspend, bxtwc_tmu_resume);
115
116static const struct platform_device_id bxt_wcove_tmu_id_table[] = {
117	{ .name = "bxt_wcove_tmu" },
118	{},
119};
120MODULE_DEVICE_TABLE(platform, bxt_wcove_tmu_id_table);
121
122static 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
132module_platform_driver(bxt_wcove_tmu_driver);
133
134MODULE_LICENSE("GPL v2");
135MODULE_AUTHOR("Nilesh Bacchewar <nilesh.bacchewar@intel.com>");
136MODULE_DESCRIPTION("BXT Whiskey Cove TMU Driver");