drivers/soundwire/intel_init.c

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