1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
2 // Copyright(c) 2015-17 Intel Corporation.
3 
4 /*
5  * SDW Intel Init Routines
6  *
7  * Initializes and creates SDW devices based on ACPI and Hardware values
8  */
9 
10 #include <linux/acpi.h>
11 #include <linux/platform_device.h>
12 #include <linux/soundwire/sdw_intel.h>
13 #include "intel.h"
14 
15 #define SDW_MAX_LINKS		4
16 #define SDW_SHIM_LCAP		0x0
17 #define SDW_SHIM_BASE		0x2C000
18 #define SDW_ALH_BASE		0x2C800
19 #define SDW_LINK_BASE		0x30000
20 #define SDW_LINK_SIZE		0x10000
21 
22 struct sdw_link_data {
23 	struct sdw_intel_link_res res;
24 	struct platform_device *pdev;
25 };
26 
27 struct sdw_intel_ctx {
28 	int count;
29 	struct sdw_link_data *links;
30 };
31 
32 static int sdw_intel_cleanup_pdev(struct sdw_intel_ctx *ctx)
33 {
34 	struct sdw_link_data *link = ctx->links;
35 	int i;
36 
37 	if (!link)
38 		return 0;
39 
40 	for (i = 0; i < ctx->count; i++) {
41 		if (link->pdev)
42 			platform_device_unregister(link->pdev);
43 		link++;
44 	}
45 
46 	kfree(ctx->links);
47 	ctx->links = NULL;
48 
49 	return 0;
50 }
51 
52 static struct sdw_intel_ctx
53 *sdw_intel_add_controller(struct sdw_intel_res *res)
54 {
55 	struct platform_device_info pdevinfo;
56 	struct platform_device *pdev;
57 	struct sdw_link_data *link;
58 	struct sdw_intel_ctx *ctx;
59 	struct acpi_device *adev;
60 	int ret, i;
61 	u8 count;
62 	u32 caps;
63 
64 	if (acpi_bus_get_device(res->handle, &adev))
65 		return NULL;
66 
67 	/* Found controller, find links supported */
68 	count = 0;
69 	ret = fwnode_property_read_u8_array(acpi_fwnode_handle(adev),
70 				  "mipi-sdw-master-count", &count, 1);
71 
72 	/* Don't fail on error, continue and use hw value */
73 	if (ret) {
74 		dev_err(&adev->dev,
75 			"Failed to read mipi-sdw-master-count: %d\n", ret);
76 		count = SDW_MAX_LINKS;
77 	}
78 
79 	/* Check SNDWLCAP.LCOUNT */
80 	caps = ioread32(res->mmio_base + SDW_SHIM_BASE + SDW_SHIM_LCAP);
81 
82 	/* Check HW supported vs property value and use min of two */
83 	count = min_t(u8, caps, count);
84 
85 	/* Check count is within bounds */
86 	if (count > SDW_MAX_LINKS) {
87 		dev_err(&adev->dev, "Link count %d exceeds max %d\n",
88 						count, SDW_MAX_LINKS);
89 		return NULL;
90 	}
91 
92 	dev_dbg(&adev->dev, "Creating %d SDW Link devices\n", count);
93 
94 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
95 	if (!ctx)
96 		return NULL;
97 
98 	ctx->count = count;
99 	ctx->links = kcalloc(ctx->count, sizeof(*ctx->links), GFP_KERNEL);
100 	if (!ctx->links)
101 		goto link_err;
102 
103 	link = ctx->links;
104 
105 	/* Create SDW Master devices */
106 	for (i = 0; i < count; i++) {
107 
108 		link->res.irq = res->irq;
109 		link->res.registers = res->mmio_base + SDW_LINK_BASE
110 					+ (SDW_LINK_SIZE * i);
111 		link->res.shim = res->mmio_base + SDW_SHIM_BASE;
112 		link->res.alh = res->mmio_base + SDW_ALH_BASE;
113 
114 		link->res.ops = res->ops;
115 		link->res.arg = res->arg;
116 
117 		memset(&pdevinfo, 0, sizeof(pdevinfo));
118 
119 		pdevinfo.parent = res->parent;
120 		pdevinfo.name = "int-sdw";
121 		pdevinfo.id = i;
122 		pdevinfo.fwnode = acpi_fwnode_handle(adev);
123 		pdevinfo.data = &link->res;
124 		pdevinfo.size_data = sizeof(link->res);
125 
126 		pdev = platform_device_register_full(&pdevinfo);
127 		if (IS_ERR(pdev)) {
128 			dev_err(&adev->dev,
129 				"platform device creation failed: %ld\n",
130 				PTR_ERR(pdev));
131 			goto pdev_err;
132 		}
133 
134 		link->pdev = pdev;
135 		link++;
136 	}
137 
138 	return ctx;
139 
140 pdev_err:
141 	sdw_intel_cleanup_pdev(ctx);
142 link_err:
143 	kfree(ctx);
144 	return NULL;
145 }
146 
147 static acpi_status sdw_intel_acpi_cb(acpi_handle handle, u32 level,
148 					void *cdata, void **return_value)
149 {
150 	struct sdw_intel_res *res = cdata;
151 	struct acpi_device *adev;
152 
153 	if (acpi_bus_get_device(handle, &adev)) {
154 		dev_err(&adev->dev, "Couldn't find ACPI handle\n");
155 		return AE_NOT_FOUND;
156 	}
157 
158 	res->handle = handle;
159 	return AE_OK;
160 }
161 
162 /**
163  * sdw_intel_init() - SoundWire Intel init routine
164  * @parent_handle: ACPI parent handle
165  * @res: resource data
166  *
167  * This scans the namespace and creates SoundWire link controller devices
168  * based on the info queried.
169  */
170 void *sdw_intel_init(acpi_handle *parent_handle, struct sdw_intel_res *res)
171 {
172 	acpi_status status;
173 
174 	status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
175 					parent_handle, 1,
176 					sdw_intel_acpi_cb,
177 					NULL, res, NULL);
178 	if (ACPI_FAILURE(status))
179 		return NULL;
180 
181 	return sdw_intel_add_controller(res);
182 }
183 EXPORT_SYMBOL(sdw_intel_init);
184 
185 /**
186  * sdw_intel_exit() - SoundWire Intel exit
187  * @arg: callback context
188  *
189  * Delete the controller instances created and cleanup
190  */
191 void sdw_intel_exit(void *arg)
192 {
193 	struct sdw_intel_ctx *ctx = arg;
194 
195 	sdw_intel_cleanup_pdev(ctx);
196 	kfree(ctx);
197 }
198 EXPORT_SYMBOL(sdw_intel_exit);
199 
200 MODULE_LICENSE("Dual BSD/GPL");
201 MODULE_DESCRIPTION("Intel Soundwire Init Library");
202