drivers/soundwire/slave.c

   1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
   2 // Copyright(c) 2015-17 Intel Corporation.
   3
   4 #include <linux/acpi.h>
   5 #include <linux/of.h>
   6 #include <linux/soundwire/sdw.h>
   7 #include <linux/soundwire/sdw_type.h>
   8 #include <sound/sdca.h>
   9 #include "bus.h"
  10 #include "sysfs_local.h"
  11
  12 static void sdw_slave_release(struct device *dev)
  13 {
  14         struct sdw_slave *slave = dev_to_sdw_dev(dev);
  15
  16         mutex_destroy(&slave->sdw_dev_lock);
  17         kfree(slave);
  18 }
  19
  20 const struct device_type sdw_slave_type = {
  21         .name =         "sdw_slave",
  22         .release =      sdw_slave_release,
  23         .uevent =       sdw_slave_uevent,
  24 };
  25
  26 int sdw_slave_add(struct sdw_bus *bus,
  27                   struct sdw_slave_id *id, struct fwnode_handle *fwnode)
  28 {
  29         struct sdw_slave *slave;
  30         int ret;
  31         int i;
  32
  33         slave = kzalloc(sizeof(*slave), GFP_KERNEL);
  34         if (!slave)
  35                 return -ENOMEM;
  36
  37         /* Initialize data structure */
  38         memcpy(&slave->id, id, sizeof(*id));
  39         slave->dev.parent = bus->dev;
  40         slave->dev.fwnode = fwnode;
  41
  42         if (id->unique_id == SDW_IGNORED_UNIQUE_ID) {
  43                 /* name shall be sdw:ctrl:link:mfg:part:class */
  44                 dev_set_name(&slave->dev, "sdw:%01x:%01x:%04x:%04x:%02x",
  45                              bus->controller_id, bus->link_id, id->mfg_id, id->part_id,
  46                              id->class_id);
  47         } else {
  48                 /* name shall be sdw:ctrl:link:mfg:part:class:unique */
  49                 dev_set_name(&slave->dev, "sdw:%01x:%01x:%04x:%04x:%02x:%01x",
  50                              bus->controller_id, bus->link_id, id->mfg_id, id->part_id,
  51                              id->class_id, id->unique_id);
  52         }
  53
  54         slave->dev.bus = &sdw_bus_type;
  55         slave->dev.of_node = of_node_get(to_of_node(fwnode));
  56         slave->dev.type = &sdw_slave_type;
  57         slave->dev.groups = sdw_slave_status_attr_groups;
  58         slave->bus = bus;
  59         slave->status = SDW_SLAVE_UNATTACHED;
  60         init_completion(&slave->enumeration_complete);
  61         init_completion(&slave->initialization_complete);
  62         slave->dev_num = 0;
  63         slave->probed = false;
  64         slave->first_interrupt_done = false;
  65         mutex_init(&slave->sdw_dev_lock);
  66
  67         for (i = 0; i < SDW_MAX_PORTS; i++)
  68                 init_completion(&slave->port_ready[i]);
  69
  70         mutex_lock(&bus->bus_lock);
  71         list_add_tail(&slave->node, &bus->slaves);
  72         mutex_unlock(&bus->bus_lock);
  73
  74         /*
  75          * The Soundwire driver probe may optionally register SDCA
  76          * sub-devices, one per Function. This means the information
  77          * on the SDCA revision and the number/type of Functions need
  78          * to be extracted from platform firmware before the SoundWire
  79          * driver probe, and as a consequence before the SoundWire
  80          * device_register() below.
  81          */
  82         sdca_lookup_interface_revision(slave);
  83         sdca_lookup_functions(slave);
  84
  85         ret = device_register(&slave->dev);
  86         if (ret) {
  87                 dev_err(bus->dev, "Failed to add slave: ret %d\n", ret);
  88
  89                 /*
  90                  * On err, don't free but drop ref as this will be freed
  91                  * when release method is invoked.
  92                  */
  93                 mutex_lock(&bus->bus_lock);
  94                 list_del(&slave->node);
  95                 mutex_unlock(&bus->bus_lock);
  96                 put_device(&slave->dev);
  97
  98                 return ret;
  99         }
 100         sdw_slave_debugfs_init(slave);
 101
 102         return ret;
 103 }
 104 EXPORT_SYMBOL(sdw_slave_add);
 105
 106 #if IS_ENABLED(CONFIG_ACPI)
 107
 108 static bool find_slave(struct sdw_bus *bus,
 109                        struct acpi_device *adev,
 110                        struct sdw_slave_id *id)
 111 {
 112         unsigned int link_id;
 113         u64 addr;
 114         int ret;
 115
 116         ret = acpi_get_local_u64_address(adev->handle, &addr);
 117         if (ret < 0)
 118                 return false;
 119
 120         if (bus->ops->override_adr)
 121                 addr = bus->ops->override_adr(bus, addr);
 122
 123         if (!addr)
 124                 return false;
 125
 126         /* Extract link id from ADR, Bit 51 to 48 (included) */
 127         link_id = SDW_DISCO_LINK_ID(addr);
 128
 129         /* Check for link_id match */
 130         if (link_id != bus->link_id)
 131                 return false;
 132
 133         sdw_extract_slave_id(bus, addr, id);
 134
 135         return true;
 136 }
 137
 138 struct sdw_acpi_child_walk_data {
 139         struct sdw_bus *bus;
 140         struct acpi_device *adev;
 141         struct sdw_slave_id id;
 142         bool ignore_unique_id;
 143 };
 144
 145 static int sdw_acpi_check_duplicate(struct acpi_device *adev, void *data)
 146 {
 147         struct sdw_acpi_child_walk_data *cwd = data;
 148         struct sdw_bus *bus = cwd->bus;
 149         struct sdw_slave_id id;
 150
 151         if (adev == cwd->adev)
 152                 return 0;
 153
 154         if (!find_slave(bus, adev, &id))
 155                 return 0;
 156
 157         if (cwd->id.sdw_version != id.sdw_version || cwd->id.mfg_id != id.mfg_id ||
 158             cwd->id.part_id != id.part_id || cwd->id.class_id != id.class_id)
 159                 return 0;
 160
 161         if (cwd->id.unique_id != id.unique_id) {
 162                 dev_dbg(bus->dev,
 163                         "Valid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n",
 164                         cwd->id.unique_id, id.unique_id, cwd->id.mfg_id,
 165                         cwd->id.part_id);
 166                 cwd->ignore_unique_id = false;
 167                 return 0;
 168         }
 169
 170         dev_err(bus->dev,
 171                 "Invalid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n",
 172                 cwd->id.unique_id, id.unique_id, cwd->id.mfg_id, cwd->id.part_id);
 173         return -ENODEV;
 174 }
 175
 176 static int sdw_acpi_find_one(struct acpi_device *adev, void *data)
 177 {
 178         struct sdw_bus *bus = data;
 179         struct sdw_acpi_child_walk_data cwd = {
 180                 .bus = bus,
 181                 .adev = adev,
 182                 .ignore_unique_id = true,
 183         };
 184         int ret;
 185
 186         if (!find_slave(bus, adev, &cwd.id))
 187                 return 0;
 188
 189         /* Brute-force O(N^2) search for duplicates. */
 190         ret = acpi_dev_for_each_child(ACPI_COMPANION(bus->dev),
 191                                       sdw_acpi_check_duplicate, &cwd);
 192         if (ret)
 193                 return ret;
 194
 195         if (cwd.ignore_unique_id)
 196                 cwd.id.unique_id = SDW_IGNORED_UNIQUE_ID;
 197
 198         /* Ignore errors and continue. */
 199         sdw_slave_add(bus, &cwd.id, acpi_fwnode_handle(adev));
 200         return 0;
 201 }
 202
 203 /*
 204  * sdw_acpi_find_slaves() - Find Slave devices in Master ACPI node
 205  * @bus: SDW bus instance
 206  *
 207  * Scans Master ACPI node for SDW child Slave devices and registers it.
 208  */
 209 int sdw_acpi_find_slaves(struct sdw_bus *bus)
 210 {
 211         struct acpi_device *parent;
 212
 213         parent = ACPI_COMPANION(bus->dev);
 214         if (!parent) {
 215                 dev_err(bus->dev, "Can't find parent for acpi bind\n");
 216                 return -ENODEV;
 217         }
 218
 219         return acpi_dev_for_each_child(parent, sdw_acpi_find_one, bus);
 220 }
 221
 222 #endif
 223
 224 /*
 225  * sdw_of_find_slaves() - Find Slave devices in master device tree node
 226  * @bus: SDW bus instance
 227  *
 228  * Scans Master DT node for SDW child Slave devices and registers it.
 229  */
 230 int sdw_of_find_slaves(struct sdw_bus *bus)
 231 {
 232         struct device *dev = bus->dev;
 233         struct device_node *node;
 234
 235         for_each_child_of_node(bus->dev->of_node, node) {
 236                 int link_id, ret, len;
 237                 unsigned int sdw_version;
 238                 const char *compat = NULL;
 239                 struct sdw_slave_id id;
 240                 const __be32 *addr;
 241
 242                 compat = of_get_property(node, "compatible", NULL);
 243                 if (!compat)
 244                         continue;
 245
 246                 ret = sscanf(compat, "sdw%01x%04hx%04hx%02hhx", &sdw_version,
 247                              &id.mfg_id, &id.part_id, &id.class_id);
 248
 249                 if (ret != 4) {
 250                         dev_err(dev, "Invalid compatible string found %s\n",
 251                                 compat);
 252                         continue;
 253                 }
 254
 255                 addr = of_get_property(node, "reg", &len);
 256                 if (!addr || (len < 2 * sizeof(u32))) {
 257                         dev_err(dev, "Invalid Link and Instance ID\n");
 258                         continue;
 259                 }
 260
 261                 link_id = be32_to_cpup(addr++);
 262                 id.unique_id = be32_to_cpup(addr);
 263                 id.sdw_version = sdw_version;
 264
 265                 /* Check for link_id match */
 266                 if (link_id != bus->link_id)
 267                         continue;
 268
 269                 sdw_slave_add(bus, &id, of_fwnode_handle(node));
 270         }
 271
 272         return 0;
 273 }
 274
 275 MODULE_IMPORT_NS("SND_SOC_SDCA");