drivers/platform/x86/serial-multi-instantiate.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Serial multi-instantiate driver, pseudo driver to instantiate multiple
   4  * client devices from a single fwnode.
   5  *
   6  * Copyright 2018 Hans de Goede <hdegoede@redhat.com>
   7  */
   8
   9 #include <linux/acpi.h>
  10 #include <linux/bits.h>
  11 #include <linux/i2c.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/property.h>
  17 #include <linux/spi/spi.h>
  18 #include <linux/types.h>
  19
  20 #define IRQ_RESOURCE_TYPE       GENMASK(1, 0)
  21 #define IRQ_RESOURCE_NONE       0
  22 #define IRQ_RESOURCE_GPIO       1
  23 #define IRQ_RESOURCE_APIC       2
  24 #define IRQ_RESOURCE_AUTO   3
  25
  26 enum smi_bus_type {
  27         SMI_I2C,
  28         SMI_SPI,
  29         SMI_AUTO_DETECT,
  30 };
  31
  32 struct smi_instance {
  33         const char *type;
  34         unsigned int flags;
  35         int irq_idx;
  36 };
  37
  38 struct smi_node {
  39         enum smi_bus_type bus_type;
  40         struct smi_instance instances[];
  41 };
  42
  43 struct smi {
  44         int i2c_num;
  45         int spi_num;
  46         struct i2c_client **i2c_devs;
  47         struct spi_device **spi_devs;
  48 };
  49
  50 static int smi_get_irq(struct platform_device *pdev, struct acpi_device *adev,
  51                        const struct smi_instance *inst)
  52 {
  53         int ret;
  54
  55         switch (inst->flags & IRQ_RESOURCE_TYPE) {
  56         case IRQ_RESOURCE_AUTO:
  57                 ret = acpi_dev_gpio_irq_get(adev, inst->irq_idx);
  58                 if (ret > 0) {
  59                         dev_dbg(&pdev->dev, "Using gpio irq\n");
  60                         break;
  61                 }
  62                 ret = platform_get_irq(pdev, inst->irq_idx);
  63                 if (ret > 0) {
  64                         dev_dbg(&pdev->dev, "Using platform irq\n");
  65                         break;
  66                 }
  67                 break;
  68         case IRQ_RESOURCE_GPIO:
  69                 ret = acpi_dev_gpio_irq_get(adev, inst->irq_idx);
  70                 break;
  71         case IRQ_RESOURCE_APIC:
  72                 ret = platform_get_irq(pdev, inst->irq_idx);
  73                 break;
  74         default:
  75                 return 0;
  76         }
  77         if (ret < 0)
  78                 return dev_err_probe(&pdev->dev, ret, "Error requesting irq at index %d\n",
  79                                      inst->irq_idx);
  80
  81         return ret;
  82 }
  83
  84 static void smi_devs_unregister(struct smi *smi)
  85 {
  86 #if IS_REACHABLE(CONFIG_I2C)
  87         while (smi->i2c_num--)
  88                 i2c_unregister_device(smi->i2c_devs[smi->i2c_num]);
  89 #endif
  90
  91         if (IS_REACHABLE(CONFIG_SPI)) {
  92                 while (smi->spi_num--)
  93                         spi_unregister_device(smi->spi_devs[smi->spi_num]);
  94         }
  95 }
  96
  97 /**
  98  * smi_spi_probe - Instantiate multiple SPI devices from inst array
  99  * @pdev:       Platform device
 100  * @smi:        Internal struct for Serial multi instantiate driver
 101  * @inst_array: Array of instances to probe
 102  *
 103  * Returns the number of SPI devices instantiate, Zero if none is found or a negative error code.
 104  */
 105 static int smi_spi_probe(struct platform_device *pdev, struct smi *smi,
 106                          const struct smi_instance *inst_array)
 107 {
 108         struct device *dev = &pdev->dev;
 109         struct acpi_device *adev = ACPI_COMPANION(dev);
 110         struct spi_controller *ctlr;
 111         struct spi_device *spi_dev;
 112         char name[50];
 113         int i, ret, count;
 114
 115         ret = acpi_spi_count_resources(adev);
 116         if (ret < 0)
 117                 return ret;
 118         if (!ret)
 119                 return -ENOENT;
 120
 121         count = ret;
 122
 123         smi->spi_devs = devm_kcalloc(dev, count, sizeof(*smi->spi_devs), GFP_KERNEL);
 124         if (!smi->spi_devs)
 125                 return -ENOMEM;
 126
 127         for (i = 0; i < count && inst_array[i].type; i++) {
 128
 129                 spi_dev = acpi_spi_device_alloc(NULL, adev, i);
 130                 if (IS_ERR(spi_dev)) {
 131                         ret = dev_err_probe(dev, PTR_ERR(spi_dev), "failed to allocate SPI device %s from ACPI\n",
 132                                             dev_name(&adev->dev));
 133                         goto error;
 134                 }
 135
 136                 ctlr = spi_dev->controller;
 137
 138                 strscpy(spi_dev->modalias, inst_array[i].type);
 139
 140                 ret = smi_get_irq(pdev, adev, &inst_array[i]);
 141                 if (ret < 0) {
 142                         spi_dev_put(spi_dev);
 143                         goto error;
 144                 }
 145                 spi_dev->irq = ret;
 146
 147                 snprintf(name, sizeof(name), "%s-%s-%s.%d", dev_name(&ctlr->dev), dev_name(dev),
 148                          inst_array[i].type, i);
 149                 spi_dev->dev.init_name = name;
 150
 151                 ret = spi_add_device(spi_dev);
 152                 if (ret) {
 153                         dev_err_probe(&ctlr->dev, ret, "failed to add SPI device %s from ACPI\n",
 154                                       dev_name(&adev->dev));
 155                         spi_dev_put(spi_dev);
 156                         goto error;
 157                 }
 158
 159                 dev_dbg(dev, "SPI device %s using chip select %u", name,
 160                         spi_get_chipselect(spi_dev, 0));
 161
 162                 smi->spi_devs[i] = spi_dev;
 163                 smi->spi_num++;
 164         }
 165
 166         if (smi->spi_num < count) {
 167                 dev_dbg(dev, "Error finding driver, idx %d\n", i);
 168                 ret = -ENODEV;
 169                 goto error;
 170         }
 171
 172         dev_info(dev, "Instantiated %d SPI devices.\n", smi->spi_num);
 173
 174         return 0;
 175 error:
 176         smi_devs_unregister(smi);
 177
 178         return ret;
 179 }
 180
 181 /**
 182  * smi_i2c_probe - Instantiate multiple I2C devices from inst array
 183  * @pdev:       Platform device
 184  * @smi:        Internal struct for Serial multi instantiate driver
 185  * @inst_array: Array of instances to probe
 186  *
 187  * Returns the number of I2C devices instantiate, Zero if none is found or a negative error code.
 188  */
 189 static int smi_i2c_probe(struct platform_device *pdev, struct smi *smi,
 190                          const struct smi_instance *inst_array)
 191 {
 192         struct i2c_board_info board_info = {};
 193         struct device *dev = &pdev->dev;
 194         struct acpi_device *adev = ACPI_COMPANION(dev);
 195         char name[32];
 196         int i, ret, count;
 197
 198         ret = i2c_acpi_client_count(adev);
 199         if (ret < 0)
 200                 return ret;
 201         if (!ret)
 202                 return -ENOENT;
 203
 204         count = ret;
 205
 206         smi->i2c_devs = devm_kcalloc(dev, count, sizeof(*smi->i2c_devs), GFP_KERNEL);
 207         if (!smi->i2c_devs)
 208                 return -ENOMEM;
 209
 210         for (i = 0; i < count && inst_array[i].type; i++) {
 211                 memset(&board_info, 0, sizeof(board_info));
 212                 strscpy(board_info.type, inst_array[i].type);
 213                 snprintf(name, sizeof(name), "%s-%s.%d", dev_name(dev), inst_array[i].type, i);
 214                 board_info.dev_name = name;
 215
 216                 ret = smi_get_irq(pdev, adev, &inst_array[i]);
 217                 if (ret < 0)
 218                         goto error;
 219                 board_info.irq = ret;
 220
 221                 smi->i2c_devs[i] = i2c_acpi_new_device(dev, i, &board_info);
 222                 if (IS_ERR(smi->i2c_devs[i])) {
 223                         ret = dev_err_probe(dev, PTR_ERR(smi->i2c_devs[i]),
 224                                             "Error creating i2c-client, idx %d\n", i);
 225                         goto error;
 226                 }
 227                 smi->i2c_num++;
 228         }
 229         if (smi->i2c_num < count) {
 230                 dev_dbg(dev, "Error finding driver, idx %d\n", i);
 231                 ret = -ENODEV;
 232                 goto error;
 233         }
 234
 235         dev_info(dev, "Instantiated %d I2C devices.\n", smi->i2c_num);
 236
 237         return 0;
 238 error:
 239         smi_devs_unregister(smi);
 240
 241         return ret;
 242 }
 243
 244 static int smi_probe(struct platform_device *pdev)
 245 {
 246         struct device *dev = &pdev->dev;
 247         const struct smi_node *node;
 248         struct smi *smi;
 249         int ret;
 250
 251         node = device_get_match_data(dev);
 252         if (!node) {
 253                 dev_dbg(dev, "Error ACPI match data is missing\n");
 254                 return -ENODEV;
 255         }
 256
 257         smi = devm_kzalloc(dev, sizeof(*smi), GFP_KERNEL);
 258         if (!smi)
 259                 return -ENOMEM;
 260
 261         platform_set_drvdata(pdev, smi);
 262
 263         switch (node->bus_type) {
 264         case SMI_I2C:
 265                 if (IS_REACHABLE(CONFIG_I2C))
 266                         return smi_i2c_probe(pdev, smi, node->instances);
 267
 268                 return -ENODEV;
 269         case SMI_SPI:
 270                 if (IS_REACHABLE(CONFIG_SPI))
 271                         return smi_spi_probe(pdev, smi, node->instances);
 272
 273                 return -ENODEV;
 274         case SMI_AUTO_DETECT:
 275                 /*
 276                  * For backwards-compatibility with the existing nodes I2C
 277                  * is checked first and if such entries are found ONLY I2C
 278                  * devices are created. Since some existing nodes that were
 279                  * already handled by this driver could also contain unrelated
 280                  * SpiSerialBus nodes that were previously ignored, and this
 281                  * preserves that behavior.
 282                  */
 283                 if (IS_REACHABLE(CONFIG_I2C)) {
 284                         ret = smi_i2c_probe(pdev, smi, node->instances);
 285                         if (ret != -ENOENT)
 286                                 return ret;
 287                 }
 288
 289                 if (IS_REACHABLE(CONFIG_SPI))
 290                         return smi_spi_probe(pdev, smi, node->instances);
 291
 292                 return -ENODEV;
 293         default:
 294                 return -EINVAL;
 295         }
 296 }
 297
 298 static void smi_remove(struct platform_device *pdev)
 299 {
 300         struct smi *smi = platform_get_drvdata(pdev);
 301
 302         smi_devs_unregister(smi);
 303 }
 304
 305 static const struct smi_node bsg1160_data = {
 306         .instances = {
 307                 { "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
 308                 { "bmc150_magn" },
 309                 { "bmg160" },
 310                 {}
 311         },
 312         .bus_type = SMI_I2C,
 313 };
 314
 315 static const struct smi_node bsg2150_data = {
 316         .instances = {
 317                 { "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
 318                 { "bmc150_magn" },
 319                 /* The resources describe a 3th client, but it is not really there. */
 320                 { "bsg2150_dummy_dev" },
 321                 {}
 322         },
 323         .bus_type = SMI_I2C,
 324 };
 325
 326 static const struct smi_node int3515_data = {
 327         .instances = {
 328                 { "tps6598x", IRQ_RESOURCE_APIC, 0 },
 329                 { "tps6598x", IRQ_RESOURCE_APIC, 1 },
 330                 { "tps6598x", IRQ_RESOURCE_APIC, 2 },
 331                 { "tps6598x", IRQ_RESOURCE_APIC, 3 },
 332                 {}
 333         },
 334         .bus_type = SMI_I2C,
 335 };
 336
 337 static const struct smi_node cs35l41_hda = {
 338         .instances = {
 339                 { "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
 340                 { "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
 341                 { "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
 342                 { "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
 343                 {}
 344         },
 345         .bus_type = SMI_AUTO_DETECT,
 346 };
 347
 348 static const struct smi_node cs35l54_hda = {
 349         .instances = {
 350                 { "cs35l54-hda", IRQ_RESOURCE_AUTO, 0 },
 351                 { "cs35l54-hda", IRQ_RESOURCE_AUTO, 0 },
 352                 { "cs35l54-hda", IRQ_RESOURCE_AUTO, 0 },
 353                 { "cs35l54-hda", IRQ_RESOURCE_AUTO, 0 },
 354                 /* a 5th entry is an alias address, not a real device */
 355                 { "cs35l54-hda_dummy_dev" },
 356                 {}
 357         },
 358         .bus_type = SMI_AUTO_DETECT,
 359 };
 360
 361 static const struct smi_node cs35l56_hda = {
 362         .instances = {
 363                 { "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
 364                 { "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
 365                 { "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
 366                 { "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
 367                 /* a 5th entry is an alias address, not a real device */
 368                 { "cs35l56-hda_dummy_dev" },
 369                 {}
 370         },
 371         .bus_type = SMI_AUTO_DETECT,
 372 };
 373
 374 static const struct smi_node cs35l57_hda = {
 375         .instances = {
 376                 { "cs35l57-hda", IRQ_RESOURCE_AUTO, 0 },
 377                 { "cs35l57-hda", IRQ_RESOURCE_AUTO, 0 },
 378                 { "cs35l57-hda", IRQ_RESOURCE_AUTO, 0 },
 379                 { "cs35l57-hda", IRQ_RESOURCE_AUTO, 0 },
 380                 /* a 5th entry is an alias address, not a real device */
 381                 { "cs35l57-hda_dummy_dev" },
 382                 {}
 383         },
 384         .bus_type = SMI_AUTO_DETECT,
 385 };
 386
 387 /*
 388  * Note new device-ids must also be added to ignore_serial_bus_ids in
 389  * drivers/acpi/scan.c: acpi_device_enumeration_by_parent().
 390  */
 391 static const struct acpi_device_id smi_acpi_ids[] = {
 392         { "BSG1160", (unsigned long)&bsg1160_data },
 393         { "BSG2150", (unsigned long)&bsg2150_data },
 394         { "CSC3551", (unsigned long)&cs35l41_hda },
 395         { "CSC3554", (unsigned long)&cs35l54_hda },
 396         { "CSC3556", (unsigned long)&cs35l56_hda },
 397         { "CSC3557", (unsigned long)&cs35l57_hda },
 398         { "INT3515", (unsigned long)&int3515_data },
 399         /* Non-conforming _HID for Cirrus Logic already released */
 400         { "CLSA0100", (unsigned long)&cs35l41_hda },
 401         { "CLSA0101", (unsigned long)&cs35l41_hda },
 402         { }
 403 };
 404 MODULE_DEVICE_TABLE(acpi, smi_acpi_ids);
 405
 406 static struct platform_driver smi_driver = {
 407         .driver = {
 408                 .name = "Serial bus multi instantiate pseudo device driver",
 409                 .acpi_match_table = smi_acpi_ids,
 410         },
 411         .probe = smi_probe,
 412         .remove = smi_remove,
 413 };
 414 module_platform_driver(smi_driver);
 415
 416 MODULE_DESCRIPTION("Serial multi instantiate pseudo device driver");
 417 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
 418 MODULE_LICENSE("GPL");