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
 22struct sdw_link_data {
 23	struct sdw_intel_link_res res;
 24	struct platform_device *pdev;
 25};
 26
 27struct sdw_intel_ctx {
 28	int count;
 29	struct sdw_link_data *links;
 30};
 31
 32static 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
 52static 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		memset(&pdevinfo, 0, sizeof(pdevinfo));
115
116		pdevinfo.parent = res->parent;
117		pdevinfo.name = "int-sdw";
118		pdevinfo.id = i;
119		pdevinfo.fwnode = acpi_fwnode_handle(adev);
120		pdevinfo.data = &link->res;
121		pdevinfo.size_data = sizeof(link->res);
122
123		pdev = platform_device_register_full(&pdevinfo);
124		if (IS_ERR(pdev)) {
125			dev_err(&adev->dev,
126				"platform device creation failed: %ld\n",
127				PTR_ERR(pdev));
128			goto pdev_err;
129		}
130
131		link->pdev = pdev;
132		link++;
133	}
134
135	return ctx;
136
137pdev_err:
138	sdw_intel_cleanup_pdev(ctx);
139link_err:
140	kfree(ctx);
141	return NULL;
142}
143
144static acpi_status sdw_intel_acpi_cb(acpi_handle handle, u32 level,
145					void *cdata, void **return_value)
146{
147	struct sdw_intel_res *res = cdata;
148	struct acpi_device *adev;
149
150	if (acpi_bus_get_device(handle, &adev)) {
151		dev_err(&adev->dev, "Couldn't find ACPI handle\n");
152		return AE_NOT_FOUND;
153	}
154
155	res->handle = handle;
156	return AE_OK;
157}
158
159/**
160 * sdw_intel_init() - SoundWire Intel init routine
161 * @parent_handle: ACPI parent handle
162 * @res: resource data
163 *
164 * This scans the namespace and creates SoundWire link controller devices
165 * based on the info queried.
166 */
167void *sdw_intel_init(acpi_handle *parent_handle, struct sdw_intel_res *res)
168{
169	acpi_status status;
170
171	status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
172					parent_handle, 1,
173					sdw_intel_acpi_cb,
174					NULL, res, NULL);
175	if (ACPI_FAILURE(status))
176		return NULL;
177
178	return sdw_intel_add_controller(res);
179}
180EXPORT_SYMBOL(sdw_intel_init);
181
182/**
183 * sdw_intel_exit() - SoundWire Intel exit
184 * @arg: callback context
185 *
186 * Delete the controller instances created and cleanup
187 */
188void sdw_intel_exit(void *arg)
189{
190	struct sdw_intel_ctx *ctx = arg;
191
192	sdw_intel_cleanup_pdev(ctx);
193	kfree(ctx);
194}
195EXPORT_SYMBOL(sdw_intel_exit);
196
197MODULE_LICENSE("Dual BSD/GPL");
198MODULE_DESCRIPTION("Intel Soundwire Init Library");