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         if (ret < 0)
  65                 return dev_err_probe(&pdev->dev, ret, "Error requesting irq at index %d\n",
  66                                      inst->irq_idx);
  67
  68         return ret;
  69 }
  70
  71 static void smi_devs_unregister(struct smi *smi)
  72 {
  73         while (smi->i2c_num--)
  74                 i2c_unregister_device(smi->i2c_devs[smi->i2c_num]);
  75
  76         while (smi->spi_num--)
  77                 spi_unregister_device(smi->spi_devs[smi->spi_num]);
  78 }
  79
  80 /**
  81  * smi_spi_probe - Instantiate multiple SPI devices from inst array
  82  * @pdev:       Platform device
  83  * @smi:        Internal struct for Serial multi instantiate driver
  84  * @inst_array: Array of instances to probe
  85  *
  86  * Returns the number of SPI devices instantiate, Zero if none is found or a negative error code.
  87  */
  88 static int smi_spi_probe(struct platform_device *pdev, struct smi *smi,
  89                          const struct smi_instance *inst_array)
  90 {
  91         struct device *dev = &pdev->dev;
  92         struct acpi_device *adev = ACPI_COMPANION(dev);
  93         struct spi_controller *ctlr;
  94         struct spi_device *spi_dev;
  95         char name[50];
  96         int i, ret, count;
  97
  98         ret = acpi_spi_count_resources(adev);
  99         if (ret < 0)
 100                 return ret;
 101         if (!ret)
 102                 return -ENOENT;
 103
 104         count = ret;
 105
 106         smi->spi_devs = devm_kcalloc(dev, count, sizeof(*smi->spi_devs), GFP_KERNEL);
 107         if (!smi->spi_devs)
 108                 return -ENOMEM;
 109
 110         for (i = 0; i < count && inst_array[i].type; i++) {
 111
 112                 spi_dev = acpi_spi_device_alloc(NULL, adev, i);
 113                 if (IS_ERR(spi_dev)) {
 114                         ret = dev_err_probe(dev, PTR_ERR(spi_dev), "failed to allocate SPI device %s from ACPI\n",
 115                                             dev_name(&adev->dev));
 116                         goto error;
 117                 }
 118
 119                 ctlr = spi_dev->controller;
 120
 121                 strscpy(spi_dev->modalias, inst_array[i].type, sizeof(spi_dev->modalias));
 122
 123                 ret = smi_get_irq(pdev, adev, &inst_array[i]);
 124                 if (ret < 0) {
 125                         spi_dev_put(spi_dev);
 126                         goto error;
 127                 }
 128                 spi_dev->irq = ret;
 129
 130                 snprintf(name, sizeof(name), "%s-%s-%s.%d", dev_name(&ctlr->dev), dev_name(dev),
 131                          inst_array[i].type, i);
 132                 spi_dev->dev.init_name = name;
 133
 134                 ret = spi_add_device(spi_dev);
 135                 if (ret) {
 136                         dev_err_probe(&ctlr->dev, ret, "failed to add SPI device %s from ACPI\n",
 137                                       dev_name(&adev->dev));
 138                         spi_dev_put(spi_dev);
 139                         goto error;
 140                 }
 141
 142                 dev_dbg(dev, "SPI device %s using chip select %u", name, spi_dev->chip_select);
 143
 144                 smi->spi_devs[i] = spi_dev;
 145                 smi->spi_num++;
 146         }
 147
 148         if (smi->spi_num < count) {
 149                 dev_dbg(dev, "Error finding driver, idx %d\n", i);
 150                 ret = -ENODEV;
 151                 goto error;
 152         }
 153
 154         dev_info(dev, "Instantiated %d SPI devices.\n", smi->spi_num);
 155
 156         return 0;
 157 error:
 158         smi_devs_unregister(smi);
 159
 160         return ret;
 161 }
 162
 163 /**
 164  * smi_i2c_probe - Instantiate multiple I2C devices from inst array
 165  * @pdev:       Platform device
 166  * @smi:        Internal struct for Serial multi instantiate driver
 167  * @inst_array: Array of instances to probe
 168  *
 169  * Returns the number of I2C devices instantiate, Zero if none is found or a negative error code.
 170  */
 171 static int smi_i2c_probe(struct platform_device *pdev, struct smi *smi,
 172                          const struct smi_instance *inst_array)
 173 {
 174         struct i2c_board_info board_info = {};
 175         struct device *dev = &pdev->dev;
 176         struct acpi_device *adev = ACPI_COMPANION(dev);
 177         char name[32];
 178         int i, ret, count;
 179
 180         ret = i2c_acpi_client_count(adev);
 181         if (ret < 0)
 182                 return ret;
 183         if (!ret)
 184                 return -ENOENT;
 185
 186         count = ret;
 187
 188         smi->i2c_devs = devm_kcalloc(dev, count, sizeof(*smi->i2c_devs), GFP_KERNEL);
 189         if (!smi->i2c_devs)
 190                 return -ENOMEM;
 191
 192         for (i = 0; i < count && inst_array[i].type; i++) {
 193                 memset(&board_info, 0, sizeof(board_info));
 194                 strscpy(board_info.type, inst_array[i].type, I2C_NAME_SIZE);
 195                 snprintf(name, sizeof(name), "%s-%s.%d", dev_name(dev), inst_array[i].type, i);
 196                 board_info.dev_name = name;
 197
 198                 ret = smi_get_irq(pdev, adev, &inst_array[i]);
 199                 if (ret < 0)
 200                         goto error;
 201                 board_info.irq = ret;
 202
 203                 smi->i2c_devs[i] = i2c_acpi_new_device(dev, i, &board_info);
 204                 if (IS_ERR(smi->i2c_devs[i])) {
 205                         ret = dev_err_probe(dev, PTR_ERR(smi->i2c_devs[i]),
 206                                             "Error creating i2c-client, idx %d\n", i);
 207                         goto error;
 208                 }
 209                 smi->i2c_num++;
 210         }
 211         if (smi->i2c_num < count) {
 212                 dev_dbg(dev, "Error finding driver, idx %d\n", i);
 213                 ret = -ENODEV;
 214                 goto error;
 215         }
 216
 217         dev_info(dev, "Instantiated %d I2C devices.\n", smi->i2c_num);
 218
 219         return 0;
 220 error:
 221         smi_devs_unregister(smi);
 222
 223         return ret;
 224 }
 225
 226 static int smi_probe(struct platform_device *pdev)
 227 {
 228         struct device *dev = &pdev->dev;
 229         const struct smi_node *node;
 230         struct smi *smi;
 231         int ret;
 232
 233         node = device_get_match_data(dev);
 234         if (!node) {
 235                 dev_dbg(dev, "Error ACPI match data is missing\n");
 236                 return -ENODEV;
 237         }
 238
 239         smi = devm_kzalloc(dev, sizeof(*smi), GFP_KERNEL);
 240         if (!smi)
 241                 return -ENOMEM;
 242
 243         platform_set_drvdata(pdev, smi);
 244
 245         switch (node->bus_type) {
 246         case SMI_I2C:
 247                 return smi_i2c_probe(pdev, smi, node->instances);
 248         case SMI_SPI:
 249                 return smi_spi_probe(pdev, smi, node->instances);
 250         case SMI_AUTO_DETECT:
 251                 /*
 252                  * For backwards-compatibility with the existing nodes I2C
 253                  * is checked first and if such entries are found ONLY I2C
 254                  * devices are created. Since some existing nodes that were
 255                  * already handled by this driver could also contain unrelated
 256                  * SpiSerialBus nodes that were previously ignored, and this
 257                  * preserves that behavior.
 258                  */
 259                 ret = smi_i2c_probe(pdev, smi, node->instances);
 260                 if (ret != -ENOENT)
 261                         return ret;
 262                 return smi_spi_probe(pdev, smi, node->instances);
 263         default:
 264                 return -EINVAL;
 265         }
 266 }
 267
 268 static int smi_remove(struct platform_device *pdev)
 269 {
 270         struct smi *smi = platform_get_drvdata(pdev);
 271
 272         smi_devs_unregister(smi);
 273
 274         return 0;
 275 }
 276
 277 static const struct smi_node bsg1160_data = {
 278         .instances = {
 279                 { "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
 280                 { "bmc150_magn" },
 281                 { "bmg160" },
 282                 {}
 283         },
 284         .bus_type = SMI_I2C,
 285 };
 286
 287 static const struct smi_node bsg2150_data = {
 288         .instances = {
 289                 { "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
 290                 { "bmc150_magn" },
 291                 /* The resources describe a 3th client, but it is not really there. */
 292                 { "bsg2150_dummy_dev" },
 293                 {}
 294         },
 295         .bus_type = SMI_I2C,
 296 };
 297
 298 static const struct smi_node int3515_data = {
 299         .instances = {
 300                 { "tps6598x", IRQ_RESOURCE_APIC, 0 },
 301                 { "tps6598x", IRQ_RESOURCE_APIC, 1 },
 302                 { "tps6598x", IRQ_RESOURCE_APIC, 2 },
 303                 { "tps6598x", IRQ_RESOURCE_APIC, 3 },
 304                 {}
 305         },
 306         .bus_type = SMI_I2C,
 307 };
 308
 309 static const struct smi_node cs35l41_hda = {
 310         .instances = {
 311                 { "cs35l41-hda", IRQ_RESOURCE_GPIO, 0 },
 312                 { "cs35l41-hda", IRQ_RESOURCE_GPIO, 0 },
 313                 { "cs35l41-hda", IRQ_RESOURCE_GPIO, 0 },
 314                 { "cs35l41-hda", IRQ_RESOURCE_GPIO, 0 },
 315                 {}
 316         },
 317         .bus_type = SMI_AUTO_DETECT,
 318 };
 319
 320 /*
 321  * Note new device-ids must also be added to ignore_serial_bus_ids in
 322  * drivers/acpi/scan.c: acpi_device_enumeration_by_parent().
 323  */
 324 static const struct acpi_device_id smi_acpi_ids[] = {
 325         { "BSG1160", (unsigned long)&bsg1160_data },
 326         { "BSG2150", (unsigned long)&bsg2150_data },
 327         { "CSC3551", (unsigned long)&cs35l41_hda },
 328         { "INT3515", (unsigned long)&int3515_data },
 329         /* Non-conforming _HID for Cirrus Logic already released */
 330         { "CLSA0100", (unsigned long)&cs35l41_hda },
 331         { "CLSA0101", (unsigned long)&cs35l41_hda },
 332         { }
 333 };
 334 MODULE_DEVICE_TABLE(acpi, smi_acpi_ids);
 335
 336 static struct platform_driver smi_driver = {
 337         .driver = {
 338                 .name = "Serial bus multi instantiate pseudo device driver",
 339                 .acpi_match_table = smi_acpi_ids,
 340         },
 341         .probe = smi_probe,
 342         .remove = smi_remove,
 343 };
 344 module_platform_driver(smi_driver);
 345
 346 MODULE_DESCRIPTION("Serial multi instantiate pseudo device driver");
 347 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
 348 MODULE_LICENSE("GPL");