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/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                 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
 137 pdev_err:
 138         sdw_intel_cleanup_pdev(ctx);
 139 link_err:
 140         kfree(ctx);
 141         return NULL;
 142 }
 143
 144 static 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  */
 167 void *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 }
 180 EXPORT_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  */
 188 void sdw_intel_exit(void *arg)
 189 {
 190         struct sdw_intel_ctx *ctx = arg;
 191
 192         sdw_intel_cleanup_pdev(ctx);
 193         kfree(ctx);
 194 }
 195 EXPORT_SYMBOL(sdw_intel_exit);
 196
 197 MODULE_LICENSE("Dual BSD/GPL");
 198 MODULE_DESCRIPTION("Intel Soundwire Init Library");