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/interrupt.h>
 23#include <linux/platform_device.h>
 24#include <linux/mfd/intel_soc_pmic.h>
 25
 26#define BXTWC_TMUIRQ		0x4fb6
 27#define BXTWC_MIRQLVL1		0x4e0e
 28#define BXTWC_MTMUIRQ_REG	0x4fb7
 29#define BXTWC_MIRQLVL1_MTMU	BIT(1)
 30#define BXTWC_TMU_WK_ALRM	BIT(1)
 31#define BXTWC_TMU_SYS_ALRM	BIT(2)
 32#define BXTWC_TMU_ALRM_MASK	(BXTWC_TMU_WK_ALRM | BXTWC_TMU_SYS_ALRM)
 33#define BXTWC_TMU_ALRM_IRQ	(BXTWC_TMU_WK_ALRM | BXTWC_TMU_SYS_ALRM)
 34
 35struct wcove_tmu {
 36	int irq;
 37	struct device *dev;
 38	struct regmap *regmap;
 39};
 40
 41static irqreturn_t bxt_wcove_tmu_irq_handler(int irq, void *data)
 42{
 43	struct wcove_tmu *wctmu = data;
 44	unsigned int tmu_irq;
 45
 46	/* Read TMU interrupt reg */
 47	regmap_read(wctmu->regmap, BXTWC_TMUIRQ, &tmu_irq);
 48	if (tmu_irq & BXTWC_TMU_ALRM_IRQ) {
 49		/* clear TMU irq */
 50		regmap_write(wctmu->regmap, BXTWC_TMUIRQ, tmu_irq);
 51		return IRQ_HANDLED;
 52	}
 53	return IRQ_NONE;
 54}
 55
 56static int bxt_wcove_tmu_probe(struct platform_device *pdev)
 57{
 58	struct intel_soc_pmic *pmic = dev_get_drvdata(pdev->dev.parent);
 59	struct regmap_irq_chip_data *regmap_irq_chip;
 60	struct wcove_tmu *wctmu;
 61	int ret, virq, irq;
 62
 63	wctmu = devm_kzalloc(&pdev->dev, sizeof(*wctmu), GFP_KERNEL);
 64	if (!wctmu)
 65		return -ENOMEM;
 66
 67	wctmu->dev = &pdev->dev;
 68	wctmu->regmap = pmic->regmap;
 69
 70	irq = platform_get_irq(pdev, 0);
 71
 72	if (irq < 0) {
 73		dev_err(&pdev->dev, "invalid irq %d\n", irq);
 74		return irq;
 75	}
 76
 77	regmap_irq_chip = pmic->irq_chip_data_tmu;
 78	virq = regmap_irq_get_virq(regmap_irq_chip, irq);
 79	if (virq < 0) {
 80		dev_err(&pdev->dev,
 81			"failed to get virtual interrupt=%d\n", irq);
 82		return virq;
 83	}
 84
 85	ret = devm_request_threaded_irq(&pdev->dev, virq,
 86					NULL, bxt_wcove_tmu_irq_handler,
 87					IRQF_ONESHOT, "bxt_wcove_tmu", wctmu);
 88	if (ret) {
 89		dev_err(&pdev->dev, "request irq failed: %d,virq: %d\n",
 90							ret, virq);
 91		return ret;
 92	}
 93	wctmu->irq = virq;
 94
 95	/* Unmask TMU second level Wake & System alarm */
 96	regmap_update_bits(wctmu->regmap, BXTWC_MTMUIRQ_REG,
 97				  BXTWC_TMU_ALRM_MASK, 0);
 98
 99	platform_set_drvdata(pdev, wctmu);
100	return 0;
101}
102
103static int bxt_wcove_tmu_remove(struct platform_device *pdev)
104{
105	struct wcove_tmu *wctmu = platform_get_drvdata(pdev);
106	unsigned int val;
107
108	/* Mask TMU interrupts */
109	regmap_read(wctmu->regmap, BXTWC_MIRQLVL1, &val);
110	regmap_write(wctmu->regmap, BXTWC_MIRQLVL1,
111			val | BXTWC_MIRQLVL1_MTMU);
112	regmap_read(wctmu->regmap, BXTWC_MTMUIRQ_REG, &val);
113	regmap_write(wctmu->regmap, BXTWC_MTMUIRQ_REG,
114			val | BXTWC_TMU_ALRM_MASK);
115	return 0;
116}
117
118#ifdef CONFIG_PM_SLEEP
119static int bxtwc_tmu_suspend(struct device *dev)
120{
121	struct wcove_tmu *wctmu = dev_get_drvdata(dev);
122
123	enable_irq_wake(wctmu->irq);
124	return 0;
125}
126
127static int bxtwc_tmu_resume(struct device *dev)
128{
129	struct wcove_tmu *wctmu = dev_get_drvdata(dev);
130
131	disable_irq_wake(wctmu->irq);
132	return 0;
133}
134#endif
135
136static SIMPLE_DEV_PM_OPS(bxtwc_tmu_pm_ops, bxtwc_tmu_suspend, bxtwc_tmu_resume);
137
138static const struct platform_device_id bxt_wcove_tmu_id_table[] = {
139	{ .name = "bxt_wcove_tmu" },
140	{},
141};
142MODULE_DEVICE_TABLE(platform, bxt_wcove_tmu_id_table);
143
144static struct platform_driver bxt_wcove_tmu_driver = {
145	.probe = bxt_wcove_tmu_probe,
146	.remove = bxt_wcove_tmu_remove,
147	.driver = {
148		.name = "bxt_wcove_tmu",
149		.pm     = &bxtwc_tmu_pm_ops,
150	},
151	.id_table = bxt_wcove_tmu_id_table,
152};
153
154module_platform_driver(bxt_wcove_tmu_driver);
155
156MODULE_LICENSE("GPL v2");
157MODULE_AUTHOR("Nilesh Bacchewar <nilesh.bacchewar@intel.com>");
158MODULE_DESCRIPTION("BXT Whiskey Cove TMU Driver");