xref: /openbmc/linux/drivers/acpi/acpi_apd.c (revision 19c233b7)
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 }
151