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 <[email protected]>
   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         while (smi->i2c_num--)
  87                 i2c_unregister_device(smi->i2c_devs[smi->i2c_num]);
  88
  89         while (smi->spi_num--)
  90                 spi_unregister_device(smi->spi_devs[smi->spi_num]);
  91 }
  92
  93 /**
  94  * smi_spi_probe - Instantiate multiple SPI devices from inst array
  95  * @pdev:       Platform device
  96  * @smi:        Internal struct for Serial multi instantiate driver
  97  * @inst_array: Array of instances to probe
  98  *
  99  * Returns the number of SPI devices instantiate, Zero if none is found or a negative error code.
 100  */
 101 static int smi_spi_probe(struct platform_device *pdev, struct smi *smi,
 102                          const struct smi_instance *inst_array)
 103 {
 104         struct device *dev = &pdev->dev;
 105         struct acpi_device *adev = ACPI_COMPANION(dev);
 106         struct spi_controller *ctlr;
 107         struct spi_device *spi_dev;
 108         char name[50];
 109         int i, ret, count;
 110
 111         ret = acpi_spi_count_resources(adev);
 112         if (ret < 0)
 113                 return ret;
 114         if (!ret)
 115                 return -ENOENT;
 116
 117         count = ret;
 118
 119         smi->spi_devs = devm_kcalloc(dev, count, sizeof(*smi->spi_devs), GFP_KERNEL);
 120         if (!smi->spi_devs)
 121                 return -ENOMEM;
 122
 123         for (i = 0; i < count && inst_array[i].type; i++) {
 124
 125                 spi_dev = acpi_spi_device_alloc(NULL, adev, i);
 126                 if (IS_ERR(spi_dev)) {
 127                         ret = dev_err_probe(dev, PTR_ERR(spi_dev), "failed to allocate SPI device %s from ACPI\n",
 128                                             dev_name(&adev->dev));
 129                         goto error;
 130                 }
 131
 132                 ctlr = spi_dev->controller;
 133
 134                 strscpy(spi_dev->modalias, inst_array[i].type, sizeof(spi_dev->modalias));
 135
 136                 ret = smi_get_irq(pdev, adev, &inst_array[i]);
 137                 if (ret < 0) {
 138                         spi_dev_put(spi_dev);
 139                         goto error;
 140                 }
 141                 spi_dev->irq = ret;
 142
 143                 snprintf(name, sizeof(name), "%s-%s-%s.%d", dev_name(&ctlr->dev), dev_name(dev),
 144                          inst_array[i].type, i);
 145                 spi_dev->dev.init_name = name;
 146
 147                 ret = spi_add_device(spi_dev);
 148                 if (ret) {
 149                         dev_err_probe(&ctlr->dev, ret, "failed to add SPI device %s from ACPI\n",
 150                                       dev_name(&adev->dev));
 151                         spi_dev_put(spi_dev);
 152                         goto error;
 153                 }
 154
 155                 dev_dbg(dev, "SPI device %s using chip select %u", name,
 156                         spi_get_chipselect(spi_dev, 0));
 157
 158                 smi->spi_devs[i] = spi_dev;
 159                 smi->spi_num++;
 160         }
 161
 162         if (smi->spi_num < count) {
 163                 dev_dbg(dev, "Error finding driver, idx %d\n", i);
 164                 ret = -ENODEV;
 165                 goto error;
 166         }
 167
 168         dev_info(dev, "Instantiated %d SPI devices.\n", smi->spi_num);
 169
 170         return 0;
 171 error:
 172         smi_devs_unregister(smi);
 173
 174         return ret;
 175 }
 176
 177 /**
 178  * smi_i2c_probe - Instantiate multiple I2C devices from inst array
 179  * @pdev:       Platform device
 180  * @smi:        Internal struct for Serial multi instantiate driver
 181  * @inst_array: Array of instances to probe
 182  *
 183  * Returns the number of I2C devices instantiate, Zero if none is found or a negative error code.
 184  */
 185 static int smi_i2c_probe(struct platform_device *pdev, struct smi *smi,
 186                          const struct smi_instance *inst_array)
 187 {
 188         struct i2c_board_info board_info = {};
 189         struct device *dev = &pdev->dev;
 190         struct acpi_device *adev = ACPI_COMPANION(dev);
 191         char name[32];
 192         int i, ret, count;
 193
 194         ret = i2c_acpi_client_count(adev);
 195         if (ret < 0)
 196                 return ret;
 197         if (!ret)
 198                 return -ENOENT;
 199
 200         count = ret;
 201
 202         smi->i2c_devs = devm_kcalloc(dev, count, sizeof(*smi->i2c_devs), GFP_KERNEL);
 203         if (!smi->i2c_devs)
 204                 return -ENOMEM;
 205
 206         for (i = 0; i < count && inst_array[i].type; i++) {
 207                 memset(&board_info, 0, sizeof(board_info));
 208                 strscpy(board_info.type, inst_array[i].type, I2C_NAME_SIZE);
 209                 snprintf(name, sizeof(name), "%s-%s.%d", dev_name(dev), inst_array[i].type, i);
 210                 board_info.dev_name = name;
 211
 212                 ret = smi_get_irq(pdev, adev, &inst_array[i]);
 213                 if (ret < 0)
 214                         goto error;
 215                 board_info.irq = ret;
 216
 217                 smi->i2c_devs[i] = i2c_acpi_new_device(dev, i, &board_info);
 218                 if (IS_ERR(smi->i2c_devs[i])) {
 219                         ret = dev_err_probe(dev, PTR_ERR(smi->i2c_devs[i]),
 220                                             "Error creating i2c-client, idx %d\n", i);
 221                         goto error;
 222                 }
 223                 smi->i2c_num++;
 224         }
 225         if (smi->i2c_num < count) {
 226                 dev_dbg(dev, "Error finding driver, idx %d\n", i);
 227                 ret = -ENODEV;
 228                 goto error;
 229         }
 230
 231         dev_info(dev, "Instantiated %d I2C devices.\n", smi->i2c_num);
 232
 233         return 0;
 234 error:
 235         smi_devs_unregister(smi);
 236
 237         return ret;
 238 }
 239
 240 static int smi_probe(struct platform_device *pdev)
 241 {
 242         struct device *dev = &pdev->dev;
 243         const struct smi_node *node;
 244         struct smi *smi;
 245         int ret;
 246
 247         node = device_get_match_data(dev);
 248         if (!node) {
 249                 dev_dbg(dev, "Error ACPI match data is missing\n");
 250                 return -ENODEV;
 251         }
 252
 253         smi = devm_kzalloc(dev, sizeof(*smi), GFP_KERNEL);
 254         if (!smi)
 255                 return -ENOMEM;
 256
 257         platform_set_drvdata(pdev, smi);
 258
 259         switch (node->bus_type) {
 260         case SMI_I2C:
 261                 return smi_i2c_probe(pdev, smi, node->instances);
 262         case SMI_SPI:
 263                 return smi_spi_probe(pdev, smi, node->instances);
 264         case SMI_AUTO_DETECT:
 265                 /*
 266                  * For backwards-compatibility with the existing nodes I2C
 267                  * is checked first and if such entries are found ONLY I2C
 268                  * devices are created. Since some existing nodes that were
 269                  * already handled by this driver could also contain unrelated
 270                  * SpiSerialBus nodes that were previously ignored, and this
 271                  * preserves that behavior.
 272                  */
 273                 ret = smi_i2c_probe(pdev, smi, node->instances);
 274                 if (ret != -ENOENT)
 275                         return ret;
 276                 return smi_spi_probe(pdev, smi, node->instances);
 277         default:
 278                 return -EINVAL;
 279         }
 280 }
 281
 282 static void smi_remove(struct platform_device *pdev)
 283 {
 284         struct smi *smi = platform_get_drvdata(pdev);
 285
 286         smi_devs_unregister(smi);
 287 }
 288
 289 static const struct smi_node bsg1160_data = {
 290         .instances = {
 291                 { "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
 292                 { "bmc150_magn" },
 293                 { "bmg160" },
 294                 {}
 295         },
 296         .bus_type = SMI_I2C,
 297 };
 298
 299 static const struct smi_node bsg2150_data = {
 300         .instances = {
 301                 { "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
 302                 { "bmc150_magn" },
 303                 /* The resources describe a 3th client, but it is not really there. */
 304                 { "bsg2150_dummy_dev" },
 305                 {}
 306         },
 307         .bus_type = SMI_I2C,
 308 };
 309
 310 static const struct smi_node int3515_data = {
 311         .instances = {
 312                 { "tps6598x", IRQ_RESOURCE_APIC, 0 },
 313                 { "tps6598x", IRQ_RESOURCE_APIC, 1 },
 314                 { "tps6598x", IRQ_RESOURCE_APIC, 2 },
 315                 { "tps6598x", IRQ_RESOURCE_APIC, 3 },
 316                 {}
 317         },
 318         .bus_type = SMI_I2C,
 319 };
 320
 321 static const struct smi_node cs35l41_hda = {
 322         .instances = {
 323                 { "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
 324                 { "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
 325                 { "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
 326                 { "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
 327                 {}
 328         },
 329         .bus_type = SMI_AUTO_DETECT,
 330 };
 331
 332 static const struct smi_node cs35l56_hda = {
 333         .instances = {
 334                 { "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
 335                 { "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
 336                 { "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
 337                 { "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
 338                 /* a 5th entry is an alias address, not a real device */
 339                 { "cs35l56-hda_dummy_dev" },
 340                 {}
 341         },
 342         .bus_type = SMI_AUTO_DETECT,
 343 };
 344
 345 /*
 346  * Note new device-ids must also be added to ignore_serial_bus_ids in
 347  * drivers/acpi/scan.c: acpi_device_enumeration_by_parent().
 348  */
 349 static const struct acpi_device_id smi_acpi_ids[] = {
 350         { "BSG1160", (unsigned long)&bsg1160_data },
 351         { "BSG2150", (unsigned long)&bsg2150_data },
 352         { "CSC3551", (unsigned long)&cs35l41_hda },
 353         { "CSC3556", (unsigned long)&cs35l56_hda },
 354         { "INT3515", (unsigned long)&int3515_data },
 355         /* Non-conforming _HID for Cirrus Logic already released */
 356         { "CLSA0100", (unsigned long)&cs35l41_hda },
 357         { "CLSA0101", (unsigned long)&cs35l41_hda },
 358         { }
 359 };
 360 MODULE_DEVICE_TABLE(acpi, smi_acpi_ids);
 361
 362 static struct platform_driver smi_driver = {
 363         .driver = {
 364                 .name = "Serial bus multi instantiate pseudo device driver",
 365                 .acpi_match_table = smi_acpi_ids,
 366         },
 367         .probe = smi_probe,
 368         .remove_new = smi_remove,
 369 };
 370 module_platform_driver(smi_driver);
 371
 372 MODULE_DESCRIPTION("Serial multi instantiate pseudo device driver");
 373 MODULE_AUTHOR("Hans de Goede <[email protected]>");
 374 MODULE_LICENSE("GPL");