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