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 
bxt_wcove_tmu_irq_handler(int irq,void * data)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 
bxt_wcove_tmu_probe(struct platform_device * pdev)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 regmap_irq_chip_data *regmap_irq_chip;
52 	struct wcove_tmu *wctmu;
53 	int ret, virq, irq;
54 
55 	wctmu = devm_kzalloc(&pdev->dev, sizeof(*wctmu), GFP_KERNEL);
56 	if (!wctmu)
57 		return -ENOMEM;
58 
59 	wctmu->dev = &pdev->dev;
60 	wctmu->regmap = pmic->regmap;
61 
62 	irq = platform_get_irq(pdev, 0);
63 	if (irq < 0)
64 		return irq;
65 
66 	regmap_irq_chip = pmic->irq_chip_data_tmu;
67 	virq = regmap_irq_get_virq(regmap_irq_chip, irq);
68 	if (virq < 0) {
69 		dev_err(&pdev->dev,
70 			"failed to get virtual interrupt=%d\n", irq);
71 		return virq;
72 	}
73 
74 	ret = devm_request_threaded_irq(&pdev->dev, virq,
75 					NULL, bxt_wcove_tmu_irq_handler,
76 					IRQF_ONESHOT, "bxt_wcove_tmu", wctmu);
77 	if (ret) {
78 		dev_err(&pdev->dev, "request irq failed: %d,virq: %d\n",
79 							ret, virq);
80 		return ret;
81 	}
82 	wctmu->irq = virq;
83 
84 	/* Unmask TMU second level Wake & System alarm */
85 	regmap_update_bits(wctmu->regmap, BXTWC_MTMUIRQ_REG,
86 				  BXTWC_TMU_ALRM_MASK, 0);
87 
88 	platform_set_drvdata(pdev, wctmu);
89 	return 0;
90 }
91 
bxt_wcove_tmu_remove(struct platform_device * pdev)92 static void bxt_wcove_tmu_remove(struct platform_device *pdev)
93 {
94 	struct wcove_tmu *wctmu = platform_get_drvdata(pdev);
95 	unsigned int val;
96 
97 	/* Mask TMU interrupts */
98 	regmap_read(wctmu->regmap, BXTWC_MIRQLVL1, &val);
99 	regmap_write(wctmu->regmap, BXTWC_MIRQLVL1,
100 			val | BXTWC_MIRQLVL1_MTMU);
101 	regmap_read(wctmu->regmap, BXTWC_MTMUIRQ_REG, &val);
102 	regmap_write(wctmu->regmap, BXTWC_MTMUIRQ_REG,
103 			val | BXTWC_TMU_ALRM_MASK);
104 }
105 
106 #ifdef CONFIG_PM_SLEEP
bxtwc_tmu_suspend(struct device * dev)107 static int bxtwc_tmu_suspend(struct device *dev)
108 {
109 	struct wcove_tmu *wctmu = dev_get_drvdata(dev);
110 
111 	enable_irq_wake(wctmu->irq);
112 	return 0;
113 }
114 
bxtwc_tmu_resume(struct device * dev)115 static int bxtwc_tmu_resume(struct device *dev)
116 {
117 	struct wcove_tmu *wctmu = dev_get_drvdata(dev);
118 
119 	disable_irq_wake(wctmu->irq);
120 	return 0;
121 }
122 #endif
123 
124 static SIMPLE_DEV_PM_OPS(bxtwc_tmu_pm_ops, bxtwc_tmu_suspend, bxtwc_tmu_resume);
125 
126 static const struct platform_device_id bxt_wcove_tmu_id_table[] = {
127 	{ .name = "bxt_wcove_tmu" },
128 	{},
129 };
130 MODULE_DEVICE_TABLE(platform, bxt_wcove_tmu_id_table);
131 
132 static struct platform_driver bxt_wcove_tmu_driver = {
133 	.probe = bxt_wcove_tmu_probe,
134 	.remove_new = bxt_wcove_tmu_remove,
135 	.driver = {
136 		.name = "bxt_wcove_tmu",
137 		.pm     = &bxtwc_tmu_pm_ops,
138 	},
139 	.id_table = bxt_wcove_tmu_id_table,
140 };
141 
142 module_platform_driver(bxt_wcove_tmu_driver);
143 
144 MODULE_LICENSE("GPL v2");
145 MODULE_AUTHOR("Nilesh Bacchewar <nilesh.bacchewar@intel.com>");
146 MODULE_DESCRIPTION("BXT Whiskey Cove TMU Driver");
147