xref: /openbmc/linux/drivers/acpi/acpi_apd.c (revision a06c488d)
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 #if defined(CONFIG_X86_AMD_PLATFORM_DEVICE) || defined(CONFIG_ARM64)
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 #ifdef CONFIG_X86_AMD_PLATFORM_DEVICE
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 #endif
85 
86 #ifdef CONFIG_ARM64
87 static struct apd_device_desc xgene_i2c_desc = {
88 	.setup = acpi_apd_setup,
89 	.fixed_clk_rate = 100000000,
90 };
91 #endif
92 
93 #else
94 
95 #define APD_ADDR(desc) (0UL)
96 
97 #endif /* CONFIG_X86_AMD_PLATFORM_DEVICE */
98 
99 /**
100 * Create platform device during acpi scan attach handle.
101 * Return value > 0 on success of creating device.
102 */
103 static int acpi_apd_create_device(struct acpi_device *adev,
104 				   const struct acpi_device_id *id)
105 {
106 	const struct apd_device_desc *dev_desc = (void *)id->driver_data;
107 	struct apd_private_data *pdata;
108 	struct platform_device *pdev;
109 	int ret;
110 
111 	if (!dev_desc) {
112 		pdev = acpi_create_platform_device(adev);
113 		return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1;
114 	}
115 
116 	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
117 	if (!pdata)
118 		return -ENOMEM;
119 
120 	pdata->adev = adev;
121 	pdata->dev_desc = dev_desc;
122 
123 	if (dev_desc->setup) {
124 		ret = dev_desc->setup(pdata);
125 		if (ret)
126 			goto err_out;
127 	}
128 
129 	adev->driver_data = pdata;
130 	pdev = acpi_create_platform_device(adev);
131 	if (!IS_ERR_OR_NULL(pdev))
132 		return 1;
133 
134 	ret = PTR_ERR(pdev);
135 	adev->driver_data = NULL;
136 
137  err_out:
138 	kfree(pdata);
139 	return ret;
140 }
141 
142 static const struct acpi_device_id acpi_apd_device_ids[] = {
143 	/* Generic apd devices */
144 #ifdef CONFIG_X86_AMD_PLATFORM_DEVICE
145 	{ "AMD0010", APD_ADDR(cz_i2c_desc) },
146 	{ "AMD0020", APD_ADDR(cz_uart_desc) },
147 	{ "AMD0030", },
148 #endif
149 #ifdef CONFIG_ARM64
150 	{ "APMC0D0F", APD_ADDR(xgene_i2c_desc) },
151 #endif
152 	{ }
153 };
154 
155 static struct acpi_scan_handler apd_handler = {
156 	.ids = acpi_apd_device_ids,
157 	.attach = acpi_apd_create_device,
158 };
159 
160 void __init acpi_apd_init(void)
161 {
162 	acpi_scan_add_handler(&apd_handler);
163 }
164