linux/drivers/leds/leds-apu.c
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   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 */
  53struct apu_param {
  54        void __iomem *addr; /* for ioread/iowrite */
  55};
  56
  57/* LED private data */
  58struct 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 */
  65struct apu_led_profile {
  66        const char *name;
  67        enum led_brightness brightness;
  68        unsigned long offset; /* for devm_ioremap */
  69};
  70
  71struct apu_led_pdata {
  72        struct platform_device *pdev;
  73        struct apu_led_priv *pled;
  74        spinlock_t lock;
  75};
  76
  77static struct apu_led_pdata *apu_led;
  78
  79static 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
  85static 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};
 104MODULE_DEVICE_TABLE(dmi, apu_led_dmi_table);
 105
 106static 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
 115static 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
 153error:
 154        while (i-- > 0)
 155                led_classdev_unregister(&apu_led->pled[i].cdev);
 156
 157        return err;
 158}
 159
 160static 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
 173static struct platform_driver apu_led_driver = {
 174        .driver = {
 175                .name = KBUILD_MODNAME,
 176        },
 177};
 178
 179static int __init apu_led_init(void)
 180{
 181        struct platform_device *pdev;
 182        int err;
 183
 184        if (!(dmi_match(DMI_SYS_VENDOR, "PC Engines") &&
 185              (dmi_match(DMI_PRODUCT_NAME, "APU") || dmi_match(DMI_PRODUCT_NAME, "apu1")))) {
 186                pr_err("No PC Engines APUv1 board detected. For APUv2,3 support, enable CONFIG_PCENGINES_APU2\n");
 187                return -ENODEV;
 188        }
 189
 190        pdev = platform_device_register_simple(KBUILD_MODNAME, -1, NULL, 0);
 191        if (IS_ERR(pdev)) {
 192                pr_err("Device allocation failed\n");
 193                return PTR_ERR(pdev);
 194        }
 195
 196        err = platform_driver_probe(&apu_led_driver, apu_led_probe);
 197        if (err) {
 198                pr_err("Probe platform driver failed\n");
 199                platform_device_unregister(pdev);
 200        }
 201
 202        return err;
 203}
 204
 205static void __exit apu_led_exit(void)
 206{
 207        int i;
 208
 209        for (i = 0; i < ARRAY_SIZE(apu1_led_profile); i++)
 210                led_classdev_unregister(&apu_led->pled[i].cdev);
 211
 212        platform_device_unregister(apu_led->pdev);
 213        platform_driver_unregister(&apu_led_driver);
 214}
 215
 216module_init(apu_led_init);
 217module_exit(apu_led_exit);
 218
 219MODULE_AUTHOR("Alan Mizrahi");
 220MODULE_DESCRIPTION("PC Engines APU1 front LED driver");
 221MODULE_LICENSE("GPL v2");
 222MODULE_ALIAS("platform:leds_apu");
 223