xref: /linux/drivers/leds/leds-apu.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 /*
2  * drivers/leds/leds-apu.c
3  * Copyright (C) 2017 Alan Mizrahi, alan at mizrahi dot com dot ve
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the names of the copyright holders nor the names of its
14  *    contributors may be used to endorse or promote products derived from
15  *    this software without specific prior written permission.
16  *
17  * Alternatively, this software may be distributed under the terms of the
18  * GNU General Public License ("GPL") version 2 as published by the Free
19  * Software Foundation.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
22  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
25  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
35 
36 #include <linux/dmi.h>
37 #include <linux/err.h>
38 #include <linux/init.h>
39 #include <linux/io.h>
40 #include <linux/kernel.h>
41 #include <linux/leds.h>
42 #include <linux/module.h>
43 #include <linux/platform_device.h>
44 
45 #define APU1_FCH_ACPI_MMIO_BASE 0xFED80000
46 #define APU1_FCH_GPIO_BASE      (APU1_FCH_ACPI_MMIO_BASE + 0x01BD)
47 #define APU1_LEDON              0x08
48 #define APU1_LEDOFF             0xC8
49 #define APU1_NUM_GPIO           3
50 #define APU1_IOSIZE             sizeof(u8)
51 
52 /* LED access parameters */
53 struct apu_param {
54 	void __iomem *addr; /* for ioread/iowrite */
55 };
56 
57 /* LED private data */
58 struct apu_led_priv {
59 	struct led_classdev cdev;
60 	struct apu_param param;
61 };
62 #define cdev_to_priv(c) container_of(c, struct apu_led_priv, cdev)
63 
64 /* LED profile */
65 struct apu_led_profile {
66 	const char *name;
67 	enum led_brightness brightness;
68 	unsigned long offset; /* for devm_ioremap */
69 };
70 
71 struct apu_led_pdata {
72 	struct platform_device *pdev;
73 	struct apu_led_priv *pled;
74 	spinlock_t lock;
75 };
76 
77 static struct apu_led_pdata *apu_led;
78 
79 static const struct apu_led_profile apu1_led_profile[] = {
80 	{ "apu:green:1", LED_ON,  APU1_FCH_GPIO_BASE + 0 * APU1_IOSIZE },
81 	{ "apu:green:2", LED_OFF, APU1_FCH_GPIO_BASE + 1 * APU1_IOSIZE },
82 	{ "apu:green:3", LED_OFF, APU1_FCH_GPIO_BASE + 2 * APU1_IOSIZE },
83 };
84 
85 static const struct dmi_system_id apu_led_dmi_table[] __initconst = {
86 	/* PC Engines APU with factory bios "SageBios_PCEngines_APU-45" */
87 	{
88 		.ident = "apu",
89 		.matches = {
90 			DMI_MATCH(DMI_SYS_VENDOR, "PC Engines"),
91 			DMI_MATCH(DMI_PRODUCT_NAME, "APU")
92 		}
93 	},
94 	/* PC Engines APU with "Mainline" bios >= 4.6.8 */
95 	{
96 		.ident = "apu",
97 		.matches = {
98 			DMI_MATCH(DMI_SYS_VENDOR, "PC Engines"),
99 			DMI_MATCH(DMI_PRODUCT_NAME, "apu1")
100 		}
101 	},
102 	{}
103 };
104 MODULE_DEVICE_TABLE(dmi, apu_led_dmi_table);
105 
106 static void apu1_led_brightness_set(struct led_classdev *led, enum led_brightness value)
107 {
108 	struct apu_led_priv *pled = cdev_to_priv(led);
109 
110 	spin_lock(&apu_led->lock);
111 	iowrite8(value ? APU1_LEDON : APU1_LEDOFF, pled->param.addr);
112 	spin_unlock(&apu_led->lock);
113 }
114 
115 static int apu_led_config(struct device *dev, struct apu_led_pdata *apuld)
116 {
117 	int i;
118 	int err;
119 
120 	apu_led->pled = devm_kcalloc(dev,
121 		ARRAY_SIZE(apu1_led_profile), sizeof(struct apu_led_priv),
122 		GFP_KERNEL);
123 
124 	if (!apu_led->pled)
125 		return -ENOMEM;
126 
127 	for (i = 0; i < ARRAY_SIZE(apu1_led_profile); i++) {
128 		struct apu_led_priv *pled = &apu_led->pled[i];
129 		struct led_classdev *led_cdev = &pled->cdev;
130 
131 		led_cdev->name = apu1_led_profile[i].name;
132 		led_cdev->brightness = apu1_led_profile[i].brightness;
133 		led_cdev->max_brightness = 1;
134 		led_cdev->flags = LED_CORE_SUSPENDRESUME;
135 		led_cdev->brightness_set = apu1_led_brightness_set;
136 
137 		pled->param.addr = devm_ioremap(dev,
138 				apu1_led_profile[i].offset, APU1_IOSIZE);
139 		if (!pled->param.addr) {
140 			err = -ENOMEM;
141 			goto error;
142 		}
143 
144 		err = led_classdev_register(dev, led_cdev);
145 		if (err)
146 			goto error;
147 
148 		apu1_led_brightness_set(led_cdev, apu1_led_profile[i].brightness);
149 	}
150 
151 	return 0;
152 
153 error:
154 	while (i-- > 0)
155 		led_classdev_unregister(&apu_led->pled[i].cdev);
156 
157 	return err;
158 }
159 
160 static int __init apu_led_probe(struct platform_device *pdev)
161 {
162 	apu_led = devm_kzalloc(&pdev->dev, sizeof(*apu_led), GFP_KERNEL);
163 
164 	if (!apu_led)
165 		return -ENOMEM;
166 
167 	apu_led->pdev = pdev;
168 
169 	spin_lock_init(&apu_led->lock);
170 	return apu_led_config(&pdev->dev, apu_led);
171 }
172 
173 static struct platform_driver apu_led_driver = {
174 	.driver = {
175 		.name = KBUILD_MODNAME,
176 	},
177 };
178 
179 static int __init apu_led_init(void)
180 {
181 	struct platform_device *pdev;
182 	int err;
183 
184 	if (!dmi_check_system(apu_led_dmi_table)) {
185 		pr_err("No PC Engines APUv1 board detected. For APUv2,3 support, enable CONFIG_PCENGINES_APU2\n");
186 		return -ENODEV;
187 	}
188 
189 	pdev = platform_device_register_simple(KBUILD_MODNAME, -1, NULL, 0);
190 	if (IS_ERR(pdev)) {
191 		pr_err("Device allocation failed\n");
192 		return PTR_ERR(pdev);
193 	}
194 
195 	err = platform_driver_probe(&apu_led_driver, apu_led_probe);
196 	if (err) {
197 		pr_err("Probe platform driver failed\n");
198 		platform_device_unregister(pdev);
199 	}
200 
201 	return err;
202 }
203 
204 static void __exit apu_led_exit(void)
205 {
206 	int i;
207 
208 	for (i = 0; i < ARRAY_SIZE(apu1_led_profile); i++)
209 		led_classdev_unregister(&apu_led->pled[i].cdev);
210 
211 	platform_device_unregister(apu_led->pdev);
212 	platform_driver_unregister(&apu_led_driver);
213 }
214 
215 module_init(apu_led_init);
216 module_exit(apu_led_exit);
217 
218 MODULE_AUTHOR("Alan Mizrahi");
219 MODULE_DESCRIPTION("PC Engines APU1 front LED driver");
220 MODULE_LICENSE("GPL v2");
221 MODULE_ALIAS("platform:leds_apu");
222