drivers/leds/leds-apu.c

   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");