xref: /openbmc/linux/drivers/acpi/acpi_apd.c (revision 9cfc5c90)
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 }
150