1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* |
3 | * Loongson-2 PM Support |
4 | * |
5 | * Copyright (C) 2023 Loongson Technology Corporation Limited |
6 | */ |
7 | |
8 | #include <linux/io.h> |
9 | #include <linux/of.h> |
10 | #include <linux/init.h> |
11 | #include <linux/input.h> |
12 | #include <linux/suspend.h> |
13 | #include <linux/interrupt.h> |
14 | #include <linux/of_platform.h> |
15 | #include <linux/pm_wakeirq.h> |
16 | #include <linux/platform_device.h> |
17 | #include <asm/bootinfo.h> |
18 | #include <asm/suspend.h> |
19 | |
20 | #define LOONGSON2_PM1_CNT_REG 0x14 |
21 | #define LOONGSON2_PM1_STS_REG 0x0c |
22 | #define LOONGSON2_PM1_ENA_REG 0x10 |
23 | #define LOONGSON2_GPE0_STS_REG 0x28 |
24 | #define LOONGSON2_GPE0_ENA_REG 0x2c |
25 | |
26 | #define LOONGSON2_PM1_PWRBTN_STS BIT(8) |
27 | #define LOONGSON2_PM1_PCIEXP_WAKE_STS BIT(14) |
28 | #define LOONGSON2_PM1_WAKE_STS BIT(15) |
29 | #define LOONGSON2_PM1_CNT_INT_EN BIT(0) |
30 | #define LOONGSON2_PM1_PWRBTN_EN LOONGSON2_PM1_PWRBTN_STS |
31 | |
32 | static struct loongson2_pm { |
33 | void __iomem *base; |
34 | struct input_dev *dev; |
35 | bool suspended; |
36 | } loongson2_pm; |
37 | |
38 | #define loongson2_pm_readw(reg) readw(loongson2_pm.base + reg) |
39 | #define loongson2_pm_readl(reg) readl(loongson2_pm.base + reg) |
40 | #define loongson2_pm_writew(val, reg) writew(val, loongson2_pm.base + reg) |
41 | #define loongson2_pm_writel(val, reg) writel(val, loongson2_pm.base + reg) |
42 | |
43 | static void loongson2_pm_status_clear(void) |
44 | { |
45 | u16 value; |
46 | |
47 | value = loongson2_pm_readw(LOONGSON2_PM1_STS_REG); |
48 | value |= (LOONGSON2_PM1_PWRBTN_STS | LOONGSON2_PM1_PCIEXP_WAKE_STS | |
49 | LOONGSON2_PM1_WAKE_STS); |
50 | loongson2_pm_writew(value, LOONGSON2_PM1_STS_REG); |
51 | loongson2_pm_writel(loongson2_pm_readl(LOONGSON2_GPE0_STS_REG), LOONGSON2_GPE0_STS_REG); |
52 | } |
53 | |
54 | static void loongson2_pm_irq_enable(void) |
55 | { |
56 | u16 value; |
57 | |
58 | value = loongson2_pm_readw(LOONGSON2_PM1_CNT_REG); |
59 | value |= LOONGSON2_PM1_CNT_INT_EN; |
60 | loongson2_pm_writew(value, LOONGSON2_PM1_CNT_REG); |
61 | |
62 | value = loongson2_pm_readw(LOONGSON2_PM1_ENA_REG); |
63 | value |= LOONGSON2_PM1_PWRBTN_EN; |
64 | loongson2_pm_writew(value, LOONGSON2_PM1_ENA_REG); |
65 | } |
66 | |
67 | static int loongson2_suspend_enter(suspend_state_t state) |
68 | { |
69 | loongson2_pm_status_clear(); |
70 | loongarch_common_suspend(); |
71 | loongarch_suspend_enter(); |
72 | loongarch_common_resume(); |
73 | loongson2_pm_irq_enable(); |
74 | pm_set_resume_via_firmware(); |
75 | |
76 | return 0; |
77 | } |
78 | |
79 | static int loongson2_suspend_begin(suspend_state_t state) |
80 | { |
81 | pm_set_suspend_via_firmware(); |
82 | |
83 | return 0; |
84 | } |
85 | |
86 | static int loongson2_suspend_valid_state(suspend_state_t state) |
87 | { |
88 | return (state == PM_SUSPEND_MEM); |
89 | } |
90 | |
91 | static const struct platform_suspend_ops loongson2_suspend_ops = { |
92 | .valid = loongson2_suspend_valid_state, |
93 | .begin = loongson2_suspend_begin, |
94 | .enter = loongson2_suspend_enter, |
95 | }; |
96 | |
97 | static int loongson2_power_button_init(struct device *dev, int irq) |
98 | { |
99 | int ret; |
100 | struct input_dev *button; |
101 | |
102 | button = input_allocate_device(); |
103 | if (!dev) |
104 | return -ENOMEM; |
105 | |
106 | button->name = "Power Button" ; |
107 | button->phys = "pm/button/input0" ; |
108 | button->id.bustype = BUS_HOST; |
109 | button->dev.parent = NULL; |
110 | input_set_capability(dev: button, EV_KEY, KEY_POWER); |
111 | |
112 | ret = input_register_device(button); |
113 | if (ret) |
114 | goto free_dev; |
115 | |
116 | dev_pm_set_wake_irq(dev: &button->dev, irq); |
117 | device_set_wakeup_capable(dev: &button->dev, capable: true); |
118 | device_set_wakeup_enable(dev: &button->dev, enable: true); |
119 | |
120 | loongson2_pm.dev = button; |
121 | dev_info(dev, "Power Button: Init successful!\n" ); |
122 | |
123 | return 0; |
124 | |
125 | free_dev: |
126 | input_free_device(dev: button); |
127 | |
128 | return ret; |
129 | } |
130 | |
131 | static irqreturn_t loongson2_pm_irq_handler(int irq, void *dev_id) |
132 | { |
133 | u16 status = loongson2_pm_readw(LOONGSON2_PM1_STS_REG); |
134 | |
135 | if (!loongson2_pm.suspended && (status & LOONGSON2_PM1_PWRBTN_STS)) { |
136 | pr_info("Power Button pressed...\n" ); |
137 | input_report_key(dev: loongson2_pm.dev, KEY_POWER, value: 1); |
138 | input_sync(dev: loongson2_pm.dev); |
139 | input_report_key(dev: loongson2_pm.dev, KEY_POWER, value: 0); |
140 | input_sync(dev: loongson2_pm.dev); |
141 | } |
142 | |
143 | loongson2_pm_status_clear(); |
144 | |
145 | return IRQ_HANDLED; |
146 | } |
147 | |
148 | static int __maybe_unused loongson2_pm_suspend(struct device *dev) |
149 | { |
150 | loongson2_pm.suspended = true; |
151 | |
152 | return 0; |
153 | } |
154 | |
155 | static int __maybe_unused loongson2_pm_resume(struct device *dev) |
156 | { |
157 | loongson2_pm.suspended = false; |
158 | |
159 | return 0; |
160 | } |
161 | static SIMPLE_DEV_PM_OPS(loongson2_pm_ops, loongson2_pm_suspend, loongson2_pm_resume); |
162 | |
163 | static int loongson2_pm_probe(struct platform_device *pdev) |
164 | { |
165 | int irq, retval; |
166 | u64 suspend_addr; |
167 | struct device *dev = &pdev->dev; |
168 | |
169 | loongson2_pm.base = devm_platform_ioremap_resource(pdev, index: 0); |
170 | if (IS_ERR(ptr: loongson2_pm.base)) |
171 | return PTR_ERR(ptr: loongson2_pm.base); |
172 | |
173 | irq = platform_get_irq(pdev, 0); |
174 | if (irq < 0) |
175 | return irq; |
176 | |
177 | if (!device_property_read_u64(dev, propname: "loongson,suspend-address" , val: &suspend_addr)) |
178 | loongson_sysconf.suspend_addr = (u64)phys_to_virt(suspend_addr); |
179 | else |
180 | dev_err(dev, "No loongson,suspend-address, could not support S3!\n" ); |
181 | |
182 | if (loongson2_power_button_init(dev, irq)) |
183 | return -EINVAL; |
184 | |
185 | retval = devm_request_irq(dev: &pdev->dev, irq, handler: loongson2_pm_irq_handler, |
186 | IRQF_SHARED, devname: "pm_irq" , dev_id: &loongson2_pm); |
187 | if (retval) |
188 | return retval; |
189 | |
190 | loongson2_pm_irq_enable(); |
191 | loongson2_pm_status_clear(); |
192 | |
193 | if (loongson_sysconf.suspend_addr) |
194 | suspend_set_ops(ops: &loongson2_suspend_ops); |
195 | |
196 | /* Populate children */ |
197 | retval = devm_of_platform_populate(dev); |
198 | if (retval) |
199 | dev_err(dev, "Error populating children, reboot and poweroff might not work properly\n" ); |
200 | |
201 | return 0; |
202 | } |
203 | |
204 | static const struct of_device_id loongson2_pm_match[] = { |
205 | { .compatible = "loongson,ls2k0500-pmc" , }, |
206 | {}, |
207 | }; |
208 | |
209 | static struct platform_driver loongson2_pm_driver = { |
210 | .driver = { |
211 | .name = "ls2k-pm" , |
212 | .pm = &loongson2_pm_ops, |
213 | .of_match_table = loongson2_pm_match, |
214 | }, |
215 | .probe = loongson2_pm_probe, |
216 | }; |
217 | module_platform_driver(loongson2_pm_driver); |
218 | |
219 | MODULE_DESCRIPTION("Loongson-2 PM driver" ); |
220 | MODULE_LICENSE("GPL" ); |
221 | |