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