drivers/acpi/acpi_apd.c

   1 /*
   2  * AMD ACPI support for ACPI2platform device.
   3  *
   4  * Copyright (c) 2014,2015 AMD Corporation.
   5  * Authors: Ken Xue <Ken.Xue@amd.com>
   6  *      Wu, Jeff <Jeff.Wu@amd.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/clk-provider.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/pm_domain.h>
  16 #include <linux/clkdev.h>
  17 #include <linux/acpi.h>
  18 #include <linux/err.h>
  19 #include <linux/clk.h>
  20 #include <linux/pm.h>
  21
  22 #include "internal.h"
  23
  24 ACPI_MODULE_NAME("acpi_apd");
  25 struct apd_private_data;
  26
  27 /**
  28  * ACPI_APD_SYSFS : add device attributes in sysfs
  29  * ACPI_APD_PM : attach power domain to device
  30  */
  31 #define ACPI_APD_SYSFS  BIT(0)
  32 #define ACPI_APD_PM     BIT(1)
  33
  34 /**
  35  * struct apd_device_desc - a descriptor for apd device
  36  * @flags: device flags like %ACPI_APD_SYSFS, %ACPI_APD_PM
  37  * @fixed_clk_rate: fixed rate input clock source for acpi device;
  38  *                      0 means no fixed rate input clock source
  39  * @setup: a hook routine to set device resource during create platform device
  40  *
  41  * Device description defined as acpi_device_id.driver_data
  42  */
  43 struct apd_device_desc {
  44         unsigned int flags;
  45         unsigned int fixed_clk_rate;
  46         int (*setup)(struct apd_private_data *pdata);
  47 };
  48
  49 struct apd_private_data {
  50         struct clk *clk;
  51         struct acpi_device *adev;
  52         const struct apd_device_desc *dev_desc;
  53 };
  54
  55 #ifdef CONFIG_X86_AMD_PLATFORM_DEVICE
  56 #define APD_ADDR(desc)  ((unsigned long)&desc)
  57
  58 static int acpi_apd_setup(struct apd_private_data *pdata)
  59 {
  60         const struct apd_device_desc *dev_desc = pdata->dev_desc;
  61         struct clk *clk = ERR_PTR(-ENODEV);
  62
  63         if (dev_desc->fixed_clk_rate) {
  64                 clk = clk_register_fixed_rate(&pdata->adev->dev,
  65                                         dev_name(&pdata->adev->dev),
  66                                         NULL, CLK_IS_ROOT,
  67                                         dev_desc->fixed_clk_rate);
  68                 clk_register_clkdev(clk, NULL, dev_name(&pdata->adev->dev));
  69                 pdata->clk = clk;
  70         }
  71
  72         return 0;
  73 }
  74
  75 static struct apd_device_desc cz_i2c_desc = {
  76         .setup = acpi_apd_setup,
  77         .fixed_clk_rate = 133000000,
  78 };
  79
  80 static struct apd_device_desc cz_uart_desc = {
  81         .setup = acpi_apd_setup,
  82         .fixed_clk_rate = 48000000,
  83 };
  84
  85 #else
  86
  87 #define APD_ADDR(desc) (0UL)
  88
  89 #endif /* CONFIG_X86_AMD_PLATFORM_DEVICE */
  90
  91 /**
  92 * Create platform device during acpi scan attach handle.
  93 * Return value > 0 on success of creating device.
  94 */
  95 static int acpi_apd_create_device(struct acpi_device *adev,
  96                                    const struct acpi_device_id *id)
  97 {
  98         const struct apd_device_desc *dev_desc = (void *)id->driver_data;
  99         struct apd_private_data *pdata;
 100         struct platform_device *pdev;
 101         int ret;
 102
 103         if (!dev_desc) {
 104                 pdev = acpi_create_platform_device(adev);
 105                 return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1;
 106         }
 107
 108         pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
 109         if (!pdata)
 110                 return -ENOMEM;
 111
 112         pdata->adev = adev;
 113         pdata->dev_desc = dev_desc;
 114
 115         if (dev_desc->setup) {
 116                 ret = dev_desc->setup(pdata);
 117                 if (ret)
 118                         goto err_out;
 119         }
 120
 121         adev->driver_data = pdata;
 122         pdev = acpi_create_platform_device(adev);
 123         if (!IS_ERR_OR_NULL(pdev))
 124                 return 1;
 125
 126         ret = PTR_ERR(pdev);
 127         adev->driver_data = NULL;
 128
 129  err_out:
 130         kfree(pdata);
 131         return ret;
 132 }
 133
 134 static const struct acpi_device_id acpi_apd_device_ids[] = {
 135         /* Generic apd devices */
 136         { "AMD0010", APD_ADDR(cz_i2c_desc) },
 137         { "AMD0020", APD_ADDR(cz_uart_desc) },
 138         { "AMD0030", },
 139         { }
 140 };
 141
 142 static struct acpi_scan_handler apd_handler = {
 143         .ids = acpi_apd_device_ids,
 144         .attach = acpi_apd_create_device,
 145 };
 146
 147 void __init acpi_apd_init(void)
 148 {
 149         acpi_scan_add_handler(&apd_handler);
 150 }