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
  25 enum smi_bus_type {
  26         SMI_I2C,
  27         SMI_SPI,
  28         SMI_AUTO_DETECT,
  29 };
  30
  31 struct smi_instance {
  32         const char *type;
  33         unsigned int flags;
  34         int irq_idx;
  35 };
  36
  37 struct smi_node {
  38         enum smi_bus_type bus_type;
  39         struct smi_instance instances[];
  40 };
  41
  42 struct smi {
  43         int i2c_num;
  44         int spi_num;
  45         struct i2c_client **i2c_devs;
  46         struct spi_device **spi_devs;
  47 };
  48
  49 static int smi_get_irq(struct platform_device *pdev, struct acpi_device *adev,
  50                        const struct smi_instance *inst)
  51 {
  52         int ret;
  53
  54         switch (inst->flags & IRQ_RESOURCE_TYPE) {
  55         case IRQ_RESOURCE_GPIO:
  56                 ret = acpi_dev_gpio_irq_get(adev, inst->irq_idx);
  57                 break;
  58         case IRQ_RESOURCE_APIC:
  59                 ret = platform_get_irq(pdev, inst->irq_idx);
  60                 break;
  61         default:
  62                 return 0;
  63         }
  64
  65         if (ret < 0)
  66                 dev_err_probe(&pdev->dev, ret, "Error requesting irq at index %d: %d\n",
  67                               inst->irq_idx, ret);
  68
  69         return ret;
  70 }
  71
  72 static void smi_devs_unregister(struct smi *smi)
  73 {
  74         while (smi->i2c_num > 0)
  75                 i2c_unregister_device(smi->i2c_devs[--smi->i2c_num]);
  76
  77         while (smi->spi_num > 0)
  78                 spi_unregister_device(smi->spi_devs[--smi->spi_num]);
  79 }
  80
  81 /**
  82  * smi_spi_probe - Instantiate multiple SPI devices from inst array
  83  * @pdev:       Platform device
  84  * @adev:       ACPI device
  85  * @smi:        Internal struct for Serial multi instantiate driver
  86  * @inst_array: Array of instances to probe
  87  *
  88  * Returns the number of SPI devices instantiate, Zero if none is found or a negative error code.
  89  */
  90 static int smi_spi_probe(struct platform_device *pdev, struct acpi_device *adev, struct smi *smi,
  91                          const struct smi_instance *inst_array)
  92 {
  93         struct device *dev = &pdev->dev;
  94         struct spi_controller *ctlr;
  95         struct spi_device *spi_dev;
  96         char name[50];
  97         int i, ret, count;
  98
  99         ret = acpi_spi_count_resources(adev);
 100         if (ret < 0)
 101                 return ret;
 102         else if (!ret)
 103                 return -ENOENT;
 104
 105         count = ret;
 106
 107         smi->spi_devs = devm_kcalloc(dev, count, sizeof(*smi->spi_devs), GFP_KERNEL);
 108         if (!smi->spi_devs)
 109                 return -ENOMEM;
 110
 111         for (i = 0; i < count && inst_array[i].type; i++) {
 112
 113                 spi_dev = acpi_spi_device_alloc(NULL, adev, i);
 114                 if (IS_ERR(spi_dev)) {
 115                         ret = PTR_ERR(spi_dev);
 116                         dev_err_probe(dev, ret, "failed to allocate SPI device %s from ACPI: %d\n",
 117                                       dev_name(&adev->dev), ret);
 118                         goto error;
 119                 }
 120
 121                 ctlr = spi_dev->controller;
 122
 123                 strscpy(spi_dev->modalias, inst_array[i].type, sizeof(spi_dev->modalias));
 124
 125                 ret = smi_get_irq(pdev, adev, &inst_array[i]);
 126                 if (ret < 0) {
 127                         spi_dev_put(spi_dev);
 128                         goto error;
 129                 }
 130                 spi_dev->irq = ret;
 131
 132                 snprintf(name, sizeof(name), "%s-%s-%s.%d", dev_name(&ctlr->dev), dev_name(dev),
 133                          inst_array[i].type, i);
 134                 spi_dev->dev.init_name = name;
 135
 136                 ret = spi_add_device(spi_dev);
 137                 if (ret) {
 138                         dev_err_probe(&ctlr->dev, ret,
 139                                       "failed to add SPI device %s from ACPI: %d\n",
 140                                       dev_name(&adev->dev), ret);
 141                         spi_dev_put(spi_dev);
 142                         goto error;
 143                 }
 144
 145                 dev_dbg(dev, "SPI device %s using chip select %u", name, spi_dev->chip_select);
 146
 147                 smi->spi_devs[i] = spi_dev;
 148                 smi->spi_num++;
 149         }
 150
 151         if (smi->spi_num < count) {
 152                 dev_dbg(dev, "Error finding driver, idx %d\n", i);
 153                 ret = -ENODEV;
 154                 goto error;
 155         }
 156
 157         dev_info(dev, "Instantiated %d SPI devices.\n", smi->spi_num);
 158
 159         return 0;
 160 error:
 161         smi_devs_unregister(smi);
 162
 163         return ret;
 164 }
 165
 166 /**
 167  * smi_i2c_probe - Instantiate multiple I2C devices from inst array
 168  * @pdev:       Platform device
 169  * @adev:       ACPI device
 170  * @smi:        Internal struct for Serial multi instantiate driver
 171  * @inst_array: Array of instances to probe
 172  *
 173  * Returns the number of I2C devices instantiate, Zero if none is found or a negative error code.
 174  */
 175 static int smi_i2c_probe(struct platform_device *pdev, struct acpi_device *adev, struct smi *smi,
 176                          const struct smi_instance *inst_array)
 177 {
 178         struct i2c_board_info board_info = {};
 179         struct device *dev = &pdev->dev;
 180         char name[32];
 181         int i, ret, count;
 182
 183         ret = i2c_acpi_client_count(adev);
 184         if (ret < 0)
 185                 return ret;
 186         else if (!ret)
 187                 return -ENOENT;
 188
 189         count = ret;
 190
 191         smi->i2c_devs = devm_kcalloc(dev, count, sizeof(*smi->i2c_devs), GFP_KERNEL);
 192         if (!smi->i2c_devs)
 193                 return -ENOMEM;
 194
 195         for (i = 0; i < count && inst_array[i].type; i++) {
 196                 memset(&board_info, 0, sizeof(board_info));
 197                 strscpy(board_info.type, inst_array[i].type, I2C_NAME_SIZE);
 198                 snprintf(name, sizeof(name), "%s-%s.%d", dev_name(dev), inst_array[i].type, i);
 199                 board_info.dev_name = name;
 200
 201                 ret = smi_get_irq(pdev, adev, &inst_array[i]);
 202                 if (ret < 0)
 203                         goto error;
 204                 board_info.irq = ret;
 205
 206                 smi->i2c_devs[i] = i2c_acpi_new_device(dev, i, &board_info);
 207                 if (IS_ERR(smi->i2c_devs[i])) {
 208                         ret = dev_err_probe(dev, PTR_ERR(smi->i2c_devs[i]),
 209                                             "Error creating i2c-client, idx %d\n", i);
 210                         goto error;
 211                 }
 212                 smi->i2c_num++;
 213         }
 214         if (smi->i2c_num < count) {
 215                 dev_dbg(dev, "Error finding driver, idx %d\n", i);
 216                 ret = -ENODEV;
 217                 goto error;
 218         }
 219
 220         dev_info(dev, "Instantiated %d I2C devices.\n", smi->i2c_num);
 221
 222         return 0;
 223 error:
 224         smi_devs_unregister(smi);
 225
 226         return ret;
 227 }
 228
 229 static int smi_probe(struct platform_device *pdev)
 230 {
 231         struct device *dev = &pdev->dev;
 232         const struct smi_node *node;
 233         struct acpi_device *adev;
 234         struct smi *smi;
 235         int ret;
 236
 237         adev = ACPI_COMPANION(dev);
 238         if (!adev)
 239                 return -ENODEV;
 240
 241         node = device_get_match_data(dev);
 242         if (!node) {
 243                 dev_dbg(dev, "Error ACPI match data is missing\n");
 244                 return -ENODEV;
 245         }
 246
 247         smi = devm_kzalloc(dev, sizeof(*smi), GFP_KERNEL);
 248         if (!smi)
 249                 return -ENOMEM;
 250
 251         platform_set_drvdata(pdev, smi);
 252
 253         switch (node->bus_type) {
 254         case SMI_I2C:
 255                 return smi_i2c_probe(pdev, adev, smi, node->instances);
 256         case SMI_SPI:
 257                 return smi_spi_probe(pdev, adev, smi, node->instances);
 258         case SMI_AUTO_DETECT:
 259                 /*
 260                  * For backwards-compatibility with the existing nodes I2C
 261                  * is checked first and if such entries are found ONLY I2C
 262                  * devices are created. Since some existing nodes that were
 263                  * already handled by this driver could also contain unrelated
 264                  * SpiSerialBus nodes that were previously ignored, and this
 265                  * preserves that behavior.
 266                  */
 267                 ret = smi_i2c_probe(pdev, adev, smi, node->instances);
 268                 if (ret != -ENOENT)
 269                         return ret;
 270                 return smi_spi_probe(pdev, adev, smi, node->instances);
 271         default:
 272                 return -EINVAL;
 273         }
 274 }
 275
 276 static int smi_remove(struct platform_device *pdev)
 277 {
 278         struct smi *smi = platform_get_drvdata(pdev);
 279
 280         smi_devs_unregister(smi);
 281
 282         return 0;
 283 }
 284
 285 static const struct smi_node bsg1160_data = {
 286         .instances = {
 287                 { "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
 288                 { "bmc150_magn" },
 289                 { "bmg160" },
 290                 {}
 291         },
 292         .bus_type = SMI_I2C,
 293 };
 294
 295 static const struct smi_node bsg2150_data = {
 296         .instances = {
 297                 { "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
 298                 { "bmc150_magn" },
 299                 /* The resources describe a 3th client, but it is not really there. */
 300                 { "bsg2150_dummy_dev" },
 301                 {}
 302         },
 303         .bus_type = SMI_I2C,
 304 };
 305
 306 static const struct smi_node int3515_data = {
 307         .instances = {
 308                 { "tps6598x", IRQ_RESOURCE_APIC, 0 },
 309                 { "tps6598x", IRQ_RESOURCE_APIC, 1 },
 310                 { "tps6598x", IRQ_RESOURCE_APIC, 2 },
 311                 { "tps6598x", IRQ_RESOURCE_APIC, 3 },
 312                 {}
 313         },
 314         .bus_type = SMI_I2C,
 315 };
 316
 317 static const struct smi_node cs35l41_hda = {
 318         .instances = {
 319                 { "cs35l41-hda", IRQ_RESOURCE_GPIO, 0 },
 320                 { "cs35l41-hda", IRQ_RESOURCE_GPIO, 0 },
 321                 { "cs35l41-hda", IRQ_RESOURCE_GPIO, 0 },
 322                 { "cs35l41-hda", IRQ_RESOURCE_GPIO, 0 },
 323                 {}
 324         },
 325         .bus_type = SMI_AUTO_DETECT,
 326 };
 327
 328 /*
 329  * Note new device-ids must also be added to ignore_serial_bus_ids in
 330  * drivers/acpi/scan.c: acpi_device_enumeration_by_parent().
 331  */
 332 static const struct acpi_device_id smi_acpi_ids[] = {
 333         { "BSG1160", (unsigned long)&bsg1160_data },
 334         { "BSG2150", (unsigned long)&bsg2150_data },
 335         { "INT3515", (unsigned long)&int3515_data },
 336         { "CSC3551", (unsigned long)&cs35l41_hda },
 337         /* Non-conforming _HID for Cirrus Logic already released */
 338         { "CLSA0100", (unsigned long)&cs35l41_hda },
 339         { }
 340 };
 341 MODULE_DEVICE_TABLE(acpi, smi_acpi_ids);
 342
 343 static struct platform_driver smi_driver = {
 344         .driver = {
 345                 .name = "Serial bus multi instantiate pseudo device driver",
 346                 .acpi_match_table = smi_acpi_ids,
 347         },
 348         .probe = smi_probe,
 349         .remove = smi_remove,
 350 };
 351 module_platform_driver(smi_driver);
 352
 353 MODULE_DESCRIPTION("Serial multi instantiate pseudo device driver");
 354 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
 355 MODULE_LICENSE("GPL");