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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/export.h>
12#include <linux/io.h>
13#include <linux/module.h>
14#include <linux/platform_device.h>
15#include <linux/soundwire/sdw_intel.h>
16#include "intel.h"
17
18#define SDW_LINK_TYPE 4 /* from Intel ACPI documentation */
19#define SDW_MAX_LINKS 4
20#define SDW_SHIM_LCAP 0x0
21#define SDW_SHIM_BASE 0x2C000
22#define SDW_ALH_BASE 0x2C800
23#define SDW_LINK_BASE 0x30000
24#define SDW_LINK_SIZE 0x10000
25
26static int link_mask;
27module_param_named(sdw_link_mask, link_mask, int, 0444);
28MODULE_PARM_DESC(sdw_link_mask, "Intel link mask (one bit per link)");
29
30struct sdw_link_data {
31 struct sdw_intel_link_res res;
32 struct platform_device *pdev;
33};
34
35struct sdw_intel_ctx {
36 int count;
37 struct sdw_link_data *links;
38};
39
40static int sdw_intel_cleanup_pdev(struct sdw_intel_ctx *ctx)
41{
42 struct sdw_link_data *link = ctx->links;
43 int i;
44
45 if (!link)
46 return 0;
47
48 for (i = 0; i < ctx->count; i++) {
49 if (link->pdev)
50 platform_device_unregister(link->pdev);
51 link++;
52 }
53
54 kfree(ctx->links);
55 ctx->links = NULL;
56
57 return 0;
58}
59
60static struct sdw_intel_ctx
61*sdw_intel_add_controller(struct sdw_intel_res *res)
62{
63 struct platform_device_info pdevinfo;
64 struct platform_device *pdev;
65 struct sdw_link_data *link;
66 struct sdw_intel_ctx *ctx;
67 struct acpi_device *adev;
68 int ret, i;
69 u8 count;
70 u32 caps;
71
72 if (acpi_bus_get_device(res->handle, &adev))
73 return NULL;
74
75 /* Found controller, find links supported */
76 count = 0;
77 ret = fwnode_property_read_u8_array(acpi_fwnode_handle(adev),
78 "mipi-sdw-master-count", &count, 1);
79
80 /* Don't fail on error, continue and use hw value */
81 if (ret) {
82 dev_err(&adev->dev,
83 "Failed to read mipi-sdw-master-count: %d\n", ret);
84 count = SDW_MAX_LINKS;
85 }
86
87 /* Check SNDWLCAP.LCOUNT */
88 caps = ioread32(res->mmio_base + SDW_SHIM_BASE + SDW_SHIM_LCAP);
89 caps &= GENMASK(2, 0);
90
91 /* Check HW supported vs property value and use min of two */
92 count = min_t(u8, caps, count);
93
94 /* Check count is within bounds */
95 if (count > SDW_MAX_LINKS) {
96 dev_err(&adev->dev, "Link count %d exceeds max %d\n",
97 count, SDW_MAX_LINKS);
98 return NULL;
99 } else if (!count) {
100 dev_warn(&adev->dev, "No SoundWire links detected\n");
101 return NULL;
102 }
103
104 dev_dbg(&adev->dev, "Creating %d SDW Link devices\n", count);
105
106 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
107 if (!ctx)
108 return NULL;
109
110 ctx->count = count;
111 ctx->links = kcalloc(ctx->count, sizeof(*ctx->links), GFP_KERNEL);
112 if (!ctx->links)
113 goto link_err;
114
115 link = ctx->links;
116
117 /* Create SDW Master devices */
118 for (i = 0; i < count; i++) {
119 if (link_mask && !(link_mask & BIT(i))) {
120 dev_dbg(&adev->dev,
121 "Link %d masked, will not be enabled\n", i);
122 link++;
123 continue;
124 }
125
126 link->res.irq = res->irq;
127 link->res.registers = res->mmio_base + SDW_LINK_BASE
128 + (SDW_LINK_SIZE * i);
129 link->res.shim = res->mmio_base + SDW_SHIM_BASE;
130 link->res.alh = res->mmio_base + SDW_ALH_BASE;
131
132 link->res.ops = res->ops;
133 link->res.arg = res->arg;
134
135 memset(&pdevinfo, 0, sizeof(pdevinfo));
136
137 pdevinfo.parent = res->parent;
138 pdevinfo.name = "int-sdw";
139 pdevinfo.id = i;
140 pdevinfo.fwnode = acpi_fwnode_handle(adev);
141 pdevinfo.data = &link->res;
142 pdevinfo.size_data = sizeof(link->res);
143
144 pdev = platform_device_register_full(&pdevinfo);
145 if (IS_ERR(pdev)) {
146 dev_err(&adev->dev,
147 "platform device creation failed: %ld\n",
148 PTR_ERR(pdev));
149 goto pdev_err;
150 }
151
152 link->pdev = pdev;
153 link++;
154 }
155
156 return ctx;
157
158pdev_err:
159 sdw_intel_cleanup_pdev(ctx);
160link_err:
161 kfree(ctx);
162 return NULL;
163}
164
165static acpi_status sdw_intel_acpi_cb(acpi_handle handle, u32 level,
166 void *cdata, void **return_value)
167{
168 struct sdw_intel_res *res = cdata;
169 struct acpi_device *adev;
170 acpi_status status;
171 u64 adr;
172
173 status = acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL, &adr);
174 if (ACPI_FAILURE(status))
175 return AE_OK; /* keep going */
176
177 if (acpi_bus_get_device(handle, &adev)) {
178 pr_err("%s: Couldn't find ACPI handle\n", __func__);
179 return AE_NOT_FOUND;
180 }
181
182 res->handle = handle;
183
184 /*
185 * On some Intel platforms, multiple children of the HDAS
186 * device can be found, but only one of them is the SoundWire
187 * controller. The SNDW device is always exposed with
188 * Name(_ADR, 0x40000000), with bits 31..28 representing the
189 * SoundWire link so filter accordingly
190 */
191 if ((adr & GENMASK(31, 28)) >> 28 != SDW_LINK_TYPE)
192 return AE_OK; /* keep going */
193
194 /* device found, stop namespace walk */
195 return AE_CTRL_TERMINATE;
196}
197
198/**
199 * sdw_intel_init() - SoundWire Intel init routine
200 * @parent_handle: ACPI parent handle
201 * @res: resource data
202 *
203 * This scans the namespace and creates SoundWire link controller devices
204 * based on the info queried.
205 */
206void *sdw_intel_init(acpi_handle *parent_handle, struct sdw_intel_res *res)
207{
208 acpi_status status;
209
210 status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
211 parent_handle, 1,
212 sdw_intel_acpi_cb,
213 NULL, res, NULL);
214 if (ACPI_FAILURE(status))
215 return NULL;
216
217 return sdw_intel_add_controller(res);
218}
219EXPORT_SYMBOL(sdw_intel_init);
220
221/**
222 * sdw_intel_exit() - SoundWire Intel exit
223 * @arg: callback context
224 *
225 * Delete the controller instances created and cleanup
226 */
227void sdw_intel_exit(void *arg)
228{
229 struct sdw_intel_ctx *ctx = arg;
230
231 sdw_intel_cleanup_pdev(ctx);
232 kfree(ctx);
233}
234EXPORT_SYMBOL(sdw_intel_exit);
235
236MODULE_LICENSE("Dual BSD/GPL");
237MODULE_DESCRIPTION("Intel Soundwire Init Library");