xref: /openbmc/linux/drivers/irqchip/irq-st.c (revision 0da85d1e)
1 /*
2  *  Copyright (C) 2014 STMicroelectronics – All Rights Reserved
3  *
4  *  Author: Lee Jones <lee.jones@linaro.org>
5  *
6  *  This is a re-write of Christophe Kerello's PMU driver.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <dt-bindings/interrupt-controller/irq-st.h>
14 #include <linux/err.h>
15 #include <linux/mfd/syscon.h>
16 #include <linux/of_device.h>
17 #include <linux/platform_device.h>
18 #include <linux/regmap.h>
19 #include <linux/slab.h>
20 
21 #define STIH415_SYSCFG_642		0x0a8
22 #define STIH416_SYSCFG_7543		0x87c
23 #define STIH407_SYSCFG_5102		0x198
24 #define STID127_SYSCFG_734		0x088
25 
26 #define ST_A9_IRQ_MASK			0x001FFFFF
27 #define ST_A9_IRQ_MAX_CHANS		2
28 
29 #define ST_A9_IRQ_EN_CTI_0		BIT(0)
30 #define ST_A9_IRQ_EN_CTI_1		BIT(1)
31 #define ST_A9_IRQ_EN_PMU_0		BIT(2)
32 #define ST_A9_IRQ_EN_PMU_1		BIT(3)
33 #define ST_A9_IRQ_EN_PL310_L2		BIT(4)
34 #define ST_A9_IRQ_EN_EXT_0		BIT(5)
35 #define ST_A9_IRQ_EN_EXT_1		BIT(6)
36 #define ST_A9_IRQ_EN_EXT_2		BIT(7)
37 
38 #define ST_A9_FIQ_N_SEL(dev, chan)	(dev << (8  + (chan * 3)))
39 #define ST_A9_IRQ_N_SEL(dev, chan)	(dev << (14 + (chan * 3)))
40 #define ST_A9_EXTIRQ_INV_SEL(dev)	(dev << 20)
41 
42 struct st_irq_syscfg {
43 	struct regmap *regmap;
44 	unsigned int syscfg;
45 	unsigned int config;
46 	bool ext_inverted;
47 };
48 
49 static const struct of_device_id st_irq_syscfg_match[] = {
50 	{
51 		.compatible = "st,stih415-irq-syscfg",
52 		.data = (void *)STIH415_SYSCFG_642,
53 	},
54 	{
55 		.compatible = "st,stih416-irq-syscfg",
56 		.data = (void *)STIH416_SYSCFG_7543,
57 	},
58 	{
59 		.compatible = "st,stih407-irq-syscfg",
60 		.data = (void *)STIH407_SYSCFG_5102,
61 	},
62 	{
63 		.compatible = "st,stid127-irq-syscfg",
64 		.data = (void *)STID127_SYSCFG_734,
65 	},
66 	{}
67 };
68 
69 static int st_irq_xlate(struct platform_device *pdev,
70 			int device, int channel, bool irq)
71 {
72 	struct st_irq_syscfg *ddata = dev_get_drvdata(&pdev->dev);
73 
74 	/* Set the device enable bit. */
75 	switch (device) {
76 	case ST_IRQ_SYSCFG_EXT_0:
77 		ddata->config |= ST_A9_IRQ_EN_EXT_0;
78 		break;
79 	case ST_IRQ_SYSCFG_EXT_1:
80 		ddata->config |= ST_A9_IRQ_EN_EXT_1;
81 		break;
82 	case ST_IRQ_SYSCFG_EXT_2:
83 		ddata->config |= ST_A9_IRQ_EN_EXT_2;
84 		break;
85 	case ST_IRQ_SYSCFG_CTI_0:
86 		ddata->config |= ST_A9_IRQ_EN_CTI_0;
87 		break;
88 	case ST_IRQ_SYSCFG_CTI_1:
89 		ddata->config |= ST_A9_IRQ_EN_CTI_1;
90 		break;
91 	case ST_IRQ_SYSCFG_PMU_0:
92 		ddata->config |= ST_A9_IRQ_EN_PMU_0;
93 		break;
94 	case ST_IRQ_SYSCFG_PMU_1:
95 		ddata->config |= ST_A9_IRQ_EN_PMU_1;
96 		break;
97 	case ST_IRQ_SYSCFG_pl310_L2:
98 		ddata->config |= ST_A9_IRQ_EN_PL310_L2;
99 		break;
100 	case ST_IRQ_SYSCFG_DISABLED:
101 		return 0;
102 	default:
103 		dev_err(&pdev->dev, "Unrecognised device %d\n", device);
104 		return -EINVAL;
105 	}
106 
107 	/* Select IRQ/FIQ channel for device. */
108 	ddata->config |= irq ?
109 		ST_A9_IRQ_N_SEL(device, channel) :
110 		ST_A9_FIQ_N_SEL(device, channel);
111 
112 	return 0;
113 }
114 
115 static int st_irq_syscfg_enable(struct platform_device *pdev)
116 {
117 	struct device_node *np = pdev->dev.of_node;
118 	struct st_irq_syscfg *ddata = dev_get_drvdata(&pdev->dev);
119 	int channels, ret, i;
120 	u32 device, invert;
121 
122 	channels = of_property_count_u32_elems(np, "st,irq-device");
123 	if (channels != ST_A9_IRQ_MAX_CHANS) {
124 		dev_err(&pdev->dev, "st,enable-irq-device must have 2 elems\n");
125 		return -EINVAL;
126 	}
127 
128 	channels = of_property_count_u32_elems(np, "st,fiq-device");
129 	if (channels != ST_A9_IRQ_MAX_CHANS) {
130 		dev_err(&pdev->dev, "st,enable-fiq-device must have 2 elems\n");
131 		return -EINVAL;
132 	}
133 
134 	for (i = 0; i < ST_A9_IRQ_MAX_CHANS; i++) {
135 		of_property_read_u32_index(np, "st,irq-device", i, &device);
136 
137 		ret = st_irq_xlate(pdev, device, i, true);
138 		if (ret)
139 			return ret;
140 
141 		of_property_read_u32_index(np, "st,fiq-device", i, &device);
142 
143 		ret = st_irq_xlate(pdev, device, i, false);
144 		if (ret)
145 			return ret;
146 	}
147 
148 	/* External IRQs may be inverted. */
149 	of_property_read_u32(np, "st,invert-ext", &invert);
150 	ddata->config |= ST_A9_EXTIRQ_INV_SEL(invert);
151 
152 	return regmap_update_bits(ddata->regmap, ddata->syscfg,
153 				  ST_A9_IRQ_MASK, ddata->config);
154 }
155 
156 static int st_irq_syscfg_probe(struct platform_device *pdev)
157 {
158 	struct device_node *np = pdev->dev.of_node;
159 	const struct of_device_id *match;
160 	struct st_irq_syscfg *ddata;
161 
162 	ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
163 	if (!ddata)
164 		return -ENOMEM;
165 
166 	match = of_match_device(st_irq_syscfg_match, &pdev->dev);
167 	if (!match)
168 		return -ENODEV;
169 
170 	ddata->syscfg = (unsigned int)match->data;
171 
172 	ddata->regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
173 	if (IS_ERR(ddata->regmap)) {
174 		dev_err(&pdev->dev, "syscfg phandle missing\n");
175 		return PTR_ERR(ddata->regmap);
176 	}
177 
178 	dev_set_drvdata(&pdev->dev, ddata);
179 
180 	return st_irq_syscfg_enable(pdev);
181 }
182 
183 static int st_irq_syscfg_resume(struct device *dev)
184 {
185 	struct st_irq_syscfg *ddata = dev_get_drvdata(dev);
186 
187 	return regmap_update_bits(ddata->regmap, ddata->syscfg,
188 				  ST_A9_IRQ_MASK, ddata->config);
189 }
190 
191 static SIMPLE_DEV_PM_OPS(st_irq_syscfg_pm_ops, NULL, st_irq_syscfg_resume);
192 
193 static struct platform_driver st_irq_syscfg_driver = {
194 	.driver = {
195 		.name = "st_irq_syscfg",
196 		.pm = &st_irq_syscfg_pm_ops,
197 		.of_match_table = st_irq_syscfg_match,
198 	},
199 	.probe = st_irq_syscfg_probe,
200 };
201 
202 static int __init st_irq_syscfg_init(void)
203 {
204 	return platform_driver_register(&st_irq_syscfg_driver);
205 }
206 core_initcall(st_irq_syscfg_init);
207