xref: /openbmc/linux/drivers/leds/leds-apu.c (revision a44e4f3a)
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 	{
87 		.ident = "apu",
88 		.matches = {
89 			DMI_MATCH(DMI_SYS_VENDOR, "PC Engines"),
90 			DMI_MATCH(DMI_PRODUCT_NAME, "APU")
91 		}
92 	},
93 	{}
94 };
95 MODULE_DEVICE_TABLE(dmi, apu_led_dmi_table);
96 
97 static void apu1_led_brightness_set(struct led_classdev *led, enum led_brightness value)
98 {
99 	struct apu_led_priv *pled = cdev_to_priv(led);
100 
101 	spin_lock(&apu_led->lock);
102 	iowrite8(value ? APU1_LEDON : APU1_LEDOFF, pled->param.addr);
103 	spin_unlock(&apu_led->lock);
104 }
105 
106 static int apu_led_config(struct device *dev, struct apu_led_pdata *apuld)
107 {
108 	int i;
109 	int err;
110 
111 	apu_led->pled = devm_kcalloc(dev,
112 		ARRAY_SIZE(apu1_led_profile), sizeof(struct apu_led_priv),
113 		GFP_KERNEL);
114 
115 	if (!apu_led->pled)
116 		return -ENOMEM;
117 
118 	for (i = 0; i < ARRAY_SIZE(apu1_led_profile); i++) {
119 		struct apu_led_priv *pled = &apu_led->pled[i];
120 		struct led_classdev *led_cdev = &pled->cdev;
121 
122 		led_cdev->name = apu1_led_profile[i].name;
123 		led_cdev->brightness = apu1_led_profile[i].brightness;
124 		led_cdev->max_brightness = 1;
125 		led_cdev->flags = LED_CORE_SUSPENDRESUME;
126 		led_cdev->brightness_set = apu1_led_brightness_set;
127 
128 		pled->param.addr = devm_ioremap(dev,
129 				apu1_led_profile[i].offset, APU1_IOSIZE);
130 		if (!pled->param.addr) {
131 			err = -ENOMEM;
132 			goto error;
133 		}
134 
135 		err = led_classdev_register(dev, led_cdev);
136 		if (err)
137 			goto error;
138 
139 		apu1_led_brightness_set(led_cdev, apu1_led_profile[i].brightness);
140 	}
141 
142 	return 0;
143 
144 error:
145 	while (i-- > 0)
146 		led_classdev_unregister(&apu_led->pled[i].cdev);
147 
148 	return err;
149 }
150 
151 static int __init apu_led_probe(struct platform_device *pdev)
152 {
153 	apu_led = devm_kzalloc(&pdev->dev, sizeof(*apu_led), GFP_KERNEL);
154 
155 	if (!apu_led)
156 		return -ENOMEM;
157 
158 	apu_led->pdev = pdev;
159 
160 	spin_lock_init(&apu_led->lock);
161 	return apu_led_config(&pdev->dev, apu_led);
162 }
163 
164 static struct platform_driver apu_led_driver = {
165 	.driver = {
166 		.name = KBUILD_MODNAME,
167 	},
168 };
169 
170 static int __init apu_led_init(void)
171 {
172 	struct platform_device *pdev;
173 	int err;
174 
175 	if (!(dmi_match(DMI_SYS_VENDOR, "PC Engines") &&
176 	      dmi_match(DMI_PRODUCT_NAME, "APU"))) {
177 		pr_err("No PC Engines APUv1 board detected. For APUv2,3 support, enable CONFIG_PCENGINES_APU2\n");
178 		return -ENODEV;
179 	}
180 
181 	pdev = platform_device_register_simple(KBUILD_MODNAME, -1, NULL, 0);
182 	if (IS_ERR(pdev)) {
183 		pr_err("Device allocation failed\n");
184 		return PTR_ERR(pdev);
185 	}
186 
187 	err = platform_driver_probe(&apu_led_driver, apu_led_probe);
188 	if (err) {
189 		pr_err("Probe platform driver failed\n");
190 		platform_device_unregister(pdev);
191 	}
192 
193 	return err;
194 }
195 
196 static void __exit apu_led_exit(void)
197 {
198 	int i;
199 
200 	for (i = 0; i < ARRAY_SIZE(apu1_led_profile); i++)
201 		led_classdev_unregister(&apu_led->pled[i].cdev);
202 
203 	platform_device_unregister(apu_led->pdev);
204 	platform_driver_unregister(&apu_led_driver);
205 }
206 
207 module_init(apu_led_init);
208 module_exit(apu_led_exit);
209 
210 MODULE_AUTHOR("Alan Mizrahi");
211 MODULE_DESCRIPTION("PC Engines APU1 front LED driver");
212 MODULE_LICENSE("GPL v2");
213 MODULE_ALIAS("platform:leds_apu");
214