Thomas Gleixner | 2874c5f | 2019-05-27 08:55:01 +0200 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 2 | /* |
| 3 | * Linux I2C core ACPI support code |
| 4 | * |
| 5 | * Copyright (C) 2014 Intel Corp, Author: Lan Tianyu <tianyu.lan@intel.com> |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 6 | */ |
| 7 | |
| 8 | #include <linux/acpi.h> |
| 9 | #include <linux/device.h> |
| 10 | #include <linux/err.h> |
| 11 | #include <linux/i2c.h> |
| 12 | #include <linux/list.h> |
| 13 | #include <linux/module.h> |
| 14 | #include <linux/slab.h> |
| 15 | |
| 16 | #include "i2c-core.h" |
| 17 | |
| 18 | struct i2c_acpi_handler_data { |
| 19 | struct acpi_connection_info info; |
| 20 | struct i2c_adapter *adapter; |
| 21 | }; |
| 22 | |
| 23 | struct gsb_buffer { |
| 24 | u8 status; |
| 25 | u8 len; |
| 26 | union { |
| 27 | u16 wdata; |
| 28 | u8 bdata; |
Gustavo A. R. Silva | 492baeb | 2022-09-26 16:47:25 -0500 | [diff] [blame] | 29 | DECLARE_FLEX_ARRAY(u8, data); |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 30 | }; |
| 31 | } __packed; |
| 32 | |
| 33 | struct i2c_acpi_lookup { |
| 34 | struct i2c_board_info *info; |
| 35 | acpi_handle adapter_handle; |
| 36 | acpi_handle device_handle; |
| 37 | acpi_handle search_handle; |
| 38 | int n; |
| 39 | int index; |
| 40 | u32 speed; |
| 41 | u32 min_speed; |
Hans de Goede | 7574c0d | 2019-11-13 19:29:38 +0100 | [diff] [blame] | 42 | u32 force_speed; |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 43 | }; |
| 44 | |
Andy Shevchenko | 0d5102f | 2018-11-28 13:45:29 +0200 | [diff] [blame] | 45 | /** |
| 46 | * i2c_acpi_get_i2c_resource - Gets I2cSerialBus resource if type matches |
| 47 | * @ares: ACPI resource |
| 48 | * @i2c: Pointer to I2cSerialBus resource will be returned here |
| 49 | * |
| 50 | * Checks if the given ACPI resource is of type I2cSerialBus. |
| 51 | * In this case, returns a pointer to it to the caller. |
| 52 | * |
| 53 | * Returns true if resource type is of I2cSerialBus, otherwise false. |
| 54 | */ |
| 55 | bool i2c_acpi_get_i2c_resource(struct acpi_resource *ares, |
| 56 | struct acpi_resource_i2c_serialbus **i2c) |
| 57 | { |
| 58 | struct acpi_resource_i2c_serialbus *sb; |
| 59 | |
| 60 | if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) |
| 61 | return false; |
| 62 | |
| 63 | sb = &ares->data.i2c_serial_bus; |
| 64 | if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) |
| 65 | return false; |
| 66 | |
| 67 | *i2c = sb; |
| 68 | return true; |
| 69 | } |
| 70 | EXPORT_SYMBOL_GPL(i2c_acpi_get_i2c_resource); |
| 71 | |
Hans de Goede | 20a1b3a | 2021-08-03 18:00:41 +0200 | [diff] [blame] | 72 | static int i2c_acpi_resource_count(struct acpi_resource *ares, void *data) |
| 73 | { |
| 74 | struct acpi_resource_i2c_serialbus *sb; |
| 75 | int *count = data; |
| 76 | |
| 77 | if (i2c_acpi_get_i2c_resource(ares, &sb)) |
| 78 | *count = *count + 1; |
| 79 | |
| 80 | return 1; |
| 81 | } |
| 82 | |
| 83 | /** |
| 84 | * i2c_acpi_client_count - Count the number of I2cSerialBus resources |
| 85 | * @adev: ACPI device |
| 86 | * |
| 87 | * Returns the number of I2cSerialBus resources in the ACPI-device's |
| 88 | * resource-list; or a negative error code. |
| 89 | */ |
| 90 | int i2c_acpi_client_count(struct acpi_device *adev) |
| 91 | { |
| 92 | int ret, count = 0; |
| 93 | LIST_HEAD(r); |
| 94 | |
| 95 | ret = acpi_dev_get_resources(adev, &r, i2c_acpi_resource_count, &count); |
| 96 | if (ret < 0) |
| 97 | return ret; |
| 98 | |
| 99 | acpi_dev_free_resource_list(&r); |
| 100 | return count; |
| 101 | } |
| 102 | EXPORT_SYMBOL_GPL(i2c_acpi_client_count); |
| 103 | |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 104 | static int i2c_acpi_fill_info(struct acpi_resource *ares, void *data) |
| 105 | { |
| 106 | struct i2c_acpi_lookup *lookup = data; |
| 107 | struct i2c_board_info *info = lookup->info; |
| 108 | struct acpi_resource_i2c_serialbus *sb; |
| 109 | acpi_status status; |
| 110 | |
Andy Shevchenko | 0d5102f | 2018-11-28 13:45:29 +0200 | [diff] [blame] | 111 | if (info->addr || !i2c_acpi_get_i2c_resource(ares, &sb)) |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 112 | return 1; |
| 113 | |
| 114 | if (lookup->index != -1 && lookup->n++ != lookup->index) |
| 115 | return 1; |
| 116 | |
| 117 | status = acpi_get_handle(lookup->device_handle, |
| 118 | sb->resource_source.string_ptr, |
| 119 | &lookup->adapter_handle); |
Andy Shevchenko | 5f59d6a | 2018-11-28 13:45:28 +0200 | [diff] [blame] | 120 | if (ACPI_FAILURE(status)) |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 121 | return 1; |
| 122 | |
| 123 | info->addr = sb->slave_address; |
| 124 | lookup->speed = sb->connection_speed; |
| 125 | if (sb->access_mode == ACPI_I2C_10BIT_MODE) |
| 126 | info->flags |= I2C_CLIENT_TEN; |
| 127 | |
| 128 | return 1; |
| 129 | } |
| 130 | |
Hans de Goede | 3a4991a | 2017-07-04 15:04:48 +0200 | [diff] [blame] | 131 | static const struct acpi_device_id i2c_acpi_ignored_device_ids[] = { |
| 132 | /* |
| 133 | * ACPI video acpi_devices, which are handled by the acpi-video driver |
| 134 | * sometimes contain a SERIAL_TYPE_I2C ACPI resource, ignore these. |
| 135 | */ |
| 136 | { ACPI_VIDEO_HID, 0 }, |
| 137 | {} |
| 138 | }; |
| 139 | |
Raul E Rangel | b38f2d5 | 2022-09-29 10:19:11 -0600 | [diff] [blame] | 140 | struct i2c_acpi_irq_context { |
| 141 | int irq; |
| 142 | bool wake_capable; |
| 143 | }; |
| 144 | |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 145 | static int i2c_acpi_do_lookup(struct acpi_device *adev, |
| 146 | struct i2c_acpi_lookup *lookup) |
| 147 | { |
| 148 | struct i2c_board_info *info = lookup->info; |
| 149 | struct list_head resource_list; |
| 150 | int ret; |
| 151 | |
Hans de Goede | fb90e58 | 2021-12-03 11:28:45 +0100 | [diff] [blame] | 152 | if (acpi_bus_get_status(adev)) |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 153 | return -EINVAL; |
| 154 | |
Hans de Goede | fb90e58 | 2021-12-03 11:28:45 +0100 | [diff] [blame] | 155 | if (!acpi_dev_ready_for_enumeration(adev)) |
| 156 | return -ENODEV; |
| 157 | |
Hans de Goede | 3a4991a | 2017-07-04 15:04:48 +0200 | [diff] [blame] | 158 | if (acpi_match_device_ids(adev, i2c_acpi_ignored_device_ids) == 0) |
| 159 | return -ENODEV; |
| 160 | |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 161 | memset(info, 0, sizeof(*info)); |
| 162 | lookup->device_handle = acpi_device_handle(adev); |
| 163 | |
| 164 | /* Look up for I2cSerialBus resource */ |
| 165 | INIT_LIST_HEAD(&resource_list); |
| 166 | ret = acpi_dev_get_resources(adev, &resource_list, |
| 167 | i2c_acpi_fill_info, lookup); |
| 168 | acpi_dev_free_resource_list(&resource_list); |
| 169 | |
| 170 | if (ret < 0 || !info->addr) |
| 171 | return -EINVAL; |
| 172 | |
| 173 | return 0; |
| 174 | } |
| 175 | |
Raul E Rangel | b38f2d5 | 2022-09-29 10:19:11 -0600 | [diff] [blame] | 176 | static int i2c_acpi_add_irq_resource(struct acpi_resource *ares, void *data) |
Charles Keepax | c2223dd | 2019-06-27 10:24:07 +0100 | [diff] [blame] | 177 | { |
Raul E Rangel | b38f2d5 | 2022-09-29 10:19:11 -0600 | [diff] [blame] | 178 | struct i2c_acpi_irq_context *irq_ctx = data; |
Charles Keepax | c2223dd | 2019-06-27 10:24:07 +0100 | [diff] [blame] | 179 | struct resource r; |
| 180 | |
Raul E Rangel | b38f2d5 | 2022-09-29 10:19:11 -0600 | [diff] [blame] | 181 | if (irq_ctx->irq > 0) |
| 182 | return 1; |
| 183 | |
| 184 | if (!acpi_dev_resource_interrupt(ares, 0, &r)) |
| 185 | return 1; |
| 186 | |
| 187 | irq_ctx->irq = i2c_dev_irq_from_resources(&r, 1); |
| 188 | irq_ctx->wake_capable = r.flags & IORESOURCE_IRQ_WAKECAPABLE; |
Charles Keepax | c2223dd | 2019-06-27 10:24:07 +0100 | [diff] [blame] | 189 | |
| 190 | return 1; /* No need to add resource to the list */ |
| 191 | } |
| 192 | |
Charles Keepax | 16c9db1 | 2019-06-27 10:24:09 +0100 | [diff] [blame] | 193 | /** |
| 194 | * i2c_acpi_get_irq - get device IRQ number from ACPI |
| 195 | * @client: Pointer to the I2C client device |
Raul E Rangel | b38f2d5 | 2022-09-29 10:19:11 -0600 | [diff] [blame] | 196 | * @wake_capable: Set to true if the IRQ is wake capable |
Charles Keepax | 16c9db1 | 2019-06-27 10:24:09 +0100 | [diff] [blame] | 197 | * |
| 198 | * Find the IRQ number used by a specific client device. |
| 199 | * |
| 200 | * Return: The IRQ number or an error code. |
| 201 | */ |
Raul E Rangel | b38f2d5 | 2022-09-29 10:19:11 -0600 | [diff] [blame] | 202 | int i2c_acpi_get_irq(struct i2c_client *client, bool *wake_capable) |
Charles Keepax | a52e3b3 | 2019-06-27 10:24:08 +0100 | [diff] [blame] | 203 | { |
Charles Keepax | 16c9db1 | 2019-06-27 10:24:09 +0100 | [diff] [blame] | 204 | struct acpi_device *adev = ACPI_COMPANION(&client->dev); |
Charles Keepax | a52e3b3 | 2019-06-27 10:24:08 +0100 | [diff] [blame] | 205 | struct list_head resource_list; |
Raul E Rangel | b38f2d5 | 2022-09-29 10:19:11 -0600 | [diff] [blame] | 206 | struct i2c_acpi_irq_context irq_ctx = { |
| 207 | .irq = -ENOENT, |
| 208 | }; |
Charles Keepax | a52e3b3 | 2019-06-27 10:24:08 +0100 | [diff] [blame] | 209 | int ret; |
| 210 | |
| 211 | INIT_LIST_HEAD(&resource_list); |
| 212 | |
| 213 | ret = acpi_dev_get_resources(adev, &resource_list, |
Raul E Rangel | b38f2d5 | 2022-09-29 10:19:11 -0600 | [diff] [blame] | 214 | i2c_acpi_add_irq_resource, &irq_ctx); |
Charles Keepax | a52e3b3 | 2019-06-27 10:24:08 +0100 | [diff] [blame] | 215 | if (ret < 0) |
| 216 | return ret; |
| 217 | |
| 218 | acpi_dev_free_resource_list(&resource_list); |
| 219 | |
Raul E Rangel | b38f2d5 | 2022-09-29 10:19:11 -0600 | [diff] [blame] | 220 | if (irq_ctx.irq == -ENOENT) |
| 221 | irq_ctx.irq = acpi_dev_gpio_irq_wake_get(adev, 0, &irq_ctx.wake_capable); |
Charles Keepax | 8466b61 | 2019-06-27 10:24:10 +0100 | [diff] [blame] | 222 | |
Raul E Rangel | b38f2d5 | 2022-09-29 10:19:11 -0600 | [diff] [blame] | 223 | if (irq_ctx.irq < 0) |
| 224 | return irq_ctx.irq; |
| 225 | |
| 226 | if (wake_capable) |
| 227 | *wake_capable = irq_ctx.wake_capable; |
| 228 | |
| 229 | return irq_ctx.irq; |
Charles Keepax | a52e3b3 | 2019-06-27 10:24:08 +0100 | [diff] [blame] | 230 | } |
| 231 | |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 232 | static int i2c_acpi_get_info(struct acpi_device *adev, |
| 233 | struct i2c_board_info *info, |
| 234 | struct i2c_adapter *adapter, |
| 235 | acpi_handle *adapter_handle) |
| 236 | { |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 237 | struct i2c_acpi_lookup lookup; |
| 238 | int ret; |
| 239 | |
| 240 | memset(&lookup, 0, sizeof(lookup)); |
| 241 | lookup.info = info; |
| 242 | lookup.index = -1; |
| 243 | |
Ard Biesheuvel | 4befedc | 2019-05-24 18:26:46 +0200 | [diff] [blame] | 244 | if (acpi_device_enumerated(adev)) |
| 245 | return -EINVAL; |
| 246 | |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 247 | ret = i2c_acpi_do_lookup(adev, &lookup); |
| 248 | if (ret) |
| 249 | return ret; |
| 250 | |
| 251 | if (adapter) { |
| 252 | /* The adapter must match the one in I2cSerialBus() connector */ |
| 253 | if (ACPI_HANDLE(&adapter->dev) != lookup.adapter_handle) |
| 254 | return -ENODEV; |
| 255 | } else { |
| 256 | struct acpi_device *adapter_adev; |
| 257 | |
| 258 | /* The adapter must be present */ |
Rafael J. Wysocki | 0bc4978 | 2022-02-01 19:00:42 +0100 | [diff] [blame] | 259 | adapter_adev = acpi_fetch_acpi_dev(lookup.adapter_handle); |
| 260 | if (!adapter_adev) |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 261 | return -ENODEV; |
| 262 | if (acpi_bus_get_status(adapter_adev) || |
| 263 | !adapter_adev->status.present) |
| 264 | return -ENODEV; |
| 265 | } |
| 266 | |
| 267 | info->fwnode = acpi_fwnode_handle(adev); |
| 268 | if (adapter_handle) |
| 269 | *adapter_handle = lookup.adapter_handle; |
| 270 | |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 271 | acpi_set_modalias(adev, dev_name(&adev->dev), info->type, |
| 272 | sizeof(info->type)); |
| 273 | |
| 274 | return 0; |
| 275 | } |
| 276 | |
| 277 | static void i2c_acpi_register_device(struct i2c_adapter *adapter, |
| 278 | struct acpi_device *adev, |
| 279 | struct i2c_board_info *info) |
| 280 | { |
Hans de Goede | a6e1445c | 2021-12-30 15:17:21 +0100 | [diff] [blame] | 281 | /* |
| 282 | * Skip registration on boards where the ACPI tables are |
| 283 | * known to contain bogus I2C devices. |
| 284 | */ |
| 285 | if (acpi_quirk_skip_i2c_client_enumeration(adev)) |
| 286 | return; |
| 287 | |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 288 | adev->power.flags.ignore_parent = true; |
| 289 | acpi_device_set_enumerated(adev); |
| 290 | |
Hans de Goede | 785e21c | 2020-12-21 20:13:00 +0100 | [diff] [blame] | 291 | if (IS_ERR(i2c_new_client_device(adapter, info))) |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 292 | adev->power.flags.ignore_parent = false; |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 293 | } |
| 294 | |
| 295 | static acpi_status i2c_acpi_add_device(acpi_handle handle, u32 level, |
| 296 | void *data, void **return_value) |
| 297 | { |
| 298 | struct i2c_adapter *adapter = data; |
Rafael J. Wysocki | 0bc4978 | 2022-02-01 19:00:42 +0100 | [diff] [blame] | 299 | struct acpi_device *adev = acpi_fetch_acpi_dev(handle); |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 300 | struct i2c_board_info info; |
| 301 | |
Rafael J. Wysocki | 0bc4978 | 2022-02-01 19:00:42 +0100 | [diff] [blame] | 302 | if (!adev || i2c_acpi_get_info(adev, &info, adapter, NULL)) |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 303 | return AE_OK; |
| 304 | |
| 305 | i2c_acpi_register_device(adapter, adev, &info); |
| 306 | |
| 307 | return AE_OK; |
| 308 | } |
| 309 | |
| 310 | #define I2C_ACPI_MAX_SCAN_DEPTH 32 |
| 311 | |
| 312 | /** |
| 313 | * i2c_acpi_register_devices - enumerate I2C slave devices behind adapter |
| 314 | * @adap: pointer to adapter |
| 315 | * |
| 316 | * Enumerate all I2C slave devices behind this adapter by walking the ACPI |
| 317 | * namespace. When a device is found it will be added to the Linux device |
| 318 | * model and bound to the corresponding ACPI handle. |
| 319 | */ |
| 320 | void i2c_acpi_register_devices(struct i2c_adapter *adap) |
| 321 | { |
Daniel Scally | a9e10e5 | 2021-06-03 23:40:02 +0100 | [diff] [blame] | 322 | struct acpi_device *adev; |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 323 | acpi_status status; |
| 324 | |
| 325 | if (!has_acpi_companion(&adap->dev)) |
| 326 | return; |
| 327 | |
| 328 | status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, |
| 329 | I2C_ACPI_MAX_SCAN_DEPTH, |
| 330 | i2c_acpi_add_device, NULL, |
| 331 | adap, NULL); |
| 332 | if (ACPI_FAILURE(status)) |
| 333 | dev_warn(&adap->dev, "failed to enumerate I2C slaves\n"); |
Hans de Goede | 8058d69 | 2020-10-14 16:41:58 +0200 | [diff] [blame] | 334 | |
| 335 | if (!adap->dev.parent) |
| 336 | return; |
| 337 | |
Daniel Scally | a9e10e5 | 2021-06-03 23:40:02 +0100 | [diff] [blame] | 338 | adev = ACPI_COMPANION(adap->dev.parent); |
| 339 | if (!adev) |
Hans de Goede | 8058d69 | 2020-10-14 16:41:58 +0200 | [diff] [blame] | 340 | return; |
| 341 | |
Daniel Scally | a9e10e5 | 2021-06-03 23:40:02 +0100 | [diff] [blame] | 342 | acpi_dev_clear_dependencies(adev); |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 343 | } |
| 344 | |
Hans de Goede | 7574c0d | 2019-11-13 19:29:38 +0100 | [diff] [blame] | 345 | static const struct acpi_device_id i2c_acpi_force_400khz_device_ids[] = { |
| 346 | /* |
| 347 | * These Silead touchscreen controllers only work at 400KHz, for |
| 348 | * some reason they do not work at 100KHz. On some devices the ACPI |
| 349 | * tables list another device at their bus as only being capable |
| 350 | * of 100KHz, testing has shown that these other devices work fine |
| 351 | * at 400KHz (as can be expected of any recent i2c hw) so we force |
| 352 | * the speed of the bus to 400 KHz if a Silead device is present. |
| 353 | */ |
| 354 | { "MSSL1680", 0 }, |
| 355 | {} |
| 356 | }; |
| 357 | |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 358 | static acpi_status i2c_acpi_lookup_speed(acpi_handle handle, u32 level, |
| 359 | void *data, void **return_value) |
| 360 | { |
| 361 | struct i2c_acpi_lookup *lookup = data; |
Rafael J. Wysocki | 0bc4978 | 2022-02-01 19:00:42 +0100 | [diff] [blame] | 362 | struct acpi_device *adev = acpi_fetch_acpi_dev(handle); |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 363 | |
Rafael J. Wysocki | 0bc4978 | 2022-02-01 19:00:42 +0100 | [diff] [blame] | 364 | if (!adev || i2c_acpi_do_lookup(adev, lookup)) |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 365 | return AE_OK; |
| 366 | |
| 367 | if (lookup->search_handle != lookup->adapter_handle) |
| 368 | return AE_OK; |
| 369 | |
| 370 | if (lookup->speed <= lookup->min_speed) |
| 371 | lookup->min_speed = lookup->speed; |
| 372 | |
Hans de Goede | 7574c0d | 2019-11-13 19:29:38 +0100 | [diff] [blame] | 373 | if (acpi_match_device_ids(adev, i2c_acpi_force_400khz_device_ids) == 0) |
Andy Shevchenko | e6282fc6 | 2020-03-24 14:32:11 +0200 | [diff] [blame] | 374 | lookup->force_speed = I2C_MAX_FAST_MODE_FREQ; |
Hans de Goede | 7574c0d | 2019-11-13 19:29:38 +0100 | [diff] [blame] | 375 | |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 376 | return AE_OK; |
| 377 | } |
| 378 | |
| 379 | /** |
| 380 | * i2c_acpi_find_bus_speed - find I2C bus speed from ACPI |
| 381 | * @dev: The device owning the bus |
| 382 | * |
| 383 | * Find the I2C bus speed by walking the ACPI namespace for all I2C slaves |
| 384 | * devices connected to this bus and use the speed of slowest device. |
| 385 | * |
| 386 | * Returns the speed in Hz or zero |
| 387 | */ |
| 388 | u32 i2c_acpi_find_bus_speed(struct device *dev) |
| 389 | { |
| 390 | struct i2c_acpi_lookup lookup; |
| 391 | struct i2c_board_info dummy; |
| 392 | acpi_status status; |
| 393 | |
| 394 | if (!has_acpi_companion(dev)) |
| 395 | return 0; |
| 396 | |
| 397 | memset(&lookup, 0, sizeof(lookup)); |
| 398 | lookup.search_handle = ACPI_HANDLE(dev); |
| 399 | lookup.min_speed = UINT_MAX; |
| 400 | lookup.info = &dummy; |
| 401 | lookup.index = -1; |
| 402 | |
| 403 | status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, |
| 404 | I2C_ACPI_MAX_SCAN_DEPTH, |
| 405 | i2c_acpi_lookup_speed, NULL, |
| 406 | &lookup, NULL); |
| 407 | |
| 408 | if (ACPI_FAILURE(status)) { |
| 409 | dev_warn(dev, "unable to find I2C bus speed from ACPI\n"); |
| 410 | return 0; |
| 411 | } |
| 412 | |
Hans de Goede | 7574c0d | 2019-11-13 19:29:38 +0100 | [diff] [blame] | 413 | if (lookup.force_speed) { |
| 414 | if (lookup.force_speed != lookup.min_speed) |
| 415 | dev_warn(dev, FW_BUG "DSDT uses known not-working I2C bus speed %d, forcing it to %d\n", |
| 416 | lookup.min_speed, lookup.force_speed); |
| 417 | return lookup.force_speed; |
| 418 | } else if (lookup.min_speed != UINT_MAX) { |
| 419 | return lookup.min_speed; |
| 420 | } else { |
| 421 | return 0; |
| 422 | } |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 423 | } |
| 424 | EXPORT_SYMBOL_GPL(i2c_acpi_find_bus_speed); |
| 425 | |
Ruslan Babayev | 1e91a2e | 2019-05-28 16:02:32 -0700 | [diff] [blame] | 426 | struct i2c_adapter *i2c_acpi_find_adapter_by_handle(acpi_handle handle) |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 427 | { |
Andy Shevchenko | 0a2d47a | 2021-10-14 16:47:55 +0300 | [diff] [blame] | 428 | struct i2c_adapter *adapter; |
Suzuki K Poulose | 644bf60 | 2019-08-01 11:20:24 +0100 | [diff] [blame] | 429 | struct device *dev; |
| 430 | |
Andy Shevchenko | 0a2d47a | 2021-10-14 16:47:55 +0300 | [diff] [blame] | 431 | dev = bus_find_device(&i2c_bus_type, NULL, handle, device_match_acpi_handle); |
| 432 | if (!dev) |
| 433 | return NULL; |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 434 | |
Andy Shevchenko | 0a2d47a | 2021-10-14 16:47:55 +0300 | [diff] [blame] | 435 | adapter = i2c_verify_adapter(dev); |
| 436 | if (!adapter) |
| 437 | put_device(dev); |
| 438 | |
| 439 | return adapter; |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 440 | } |
Ruslan Babayev | 1e91a2e | 2019-05-28 16:02:32 -0700 | [diff] [blame] | 441 | EXPORT_SYMBOL_GPL(i2c_acpi_find_adapter_by_handle); |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 442 | |
| 443 | static struct i2c_client *i2c_acpi_find_client_by_adev(struct acpi_device *adev) |
| 444 | { |
Russell King (Oracle) | 373c612 | 2023-01-11 10:54:21 +0000 | [diff] [blame] | 445 | return i2c_find_device_by_fwnode(acpi_fwnode_handle(adev)); |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 446 | } |
| 447 | |
Hamish Martin | 3f858bb | 2024-03-13 11:16:32 +1300 | [diff] [blame] | 448 | static struct i2c_adapter *i2c_acpi_find_adapter_by_adev(struct acpi_device *adev) |
| 449 | { |
| 450 | return i2c_find_adapter_by_fwnode(acpi_fwnode_handle(adev)); |
| 451 | } |
| 452 | |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 453 | static int i2c_acpi_notify(struct notifier_block *nb, unsigned long value, |
| 454 | void *arg) |
| 455 | { |
| 456 | struct acpi_device *adev = arg; |
| 457 | struct i2c_board_info info; |
| 458 | acpi_handle adapter_handle; |
| 459 | struct i2c_adapter *adapter; |
| 460 | struct i2c_client *client; |
| 461 | |
| 462 | switch (value) { |
| 463 | case ACPI_RECONFIG_DEVICE_ADD: |
| 464 | if (i2c_acpi_get_info(adev, &info, NULL, &adapter_handle)) |
| 465 | break; |
| 466 | |
| 467 | adapter = i2c_acpi_find_adapter_by_handle(adapter_handle); |
| 468 | if (!adapter) |
| 469 | break; |
| 470 | |
| 471 | i2c_acpi_register_device(adapter, adev, &info); |
Jamie Iles | 6558b64 | 2021-09-22 17:57:18 +0100 | [diff] [blame] | 472 | put_device(&adapter->dev); |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 473 | break; |
| 474 | case ACPI_RECONFIG_DEVICE_REMOVE: |
| 475 | if (!acpi_device_enumerated(adev)) |
| 476 | break; |
| 477 | |
| 478 | client = i2c_acpi_find_client_by_adev(adev); |
Hamish Martin | 3f858bb | 2024-03-13 11:16:32 +1300 | [diff] [blame] | 479 | if (client) { |
| 480 | i2c_unregister_device(client); |
| 481 | put_device(&client->dev); |
| 482 | } |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 483 | |
Hamish Martin | 3f858bb | 2024-03-13 11:16:32 +1300 | [diff] [blame] | 484 | adapter = i2c_acpi_find_adapter_by_adev(adev); |
| 485 | if (adapter) { |
| 486 | acpi_unbind_one(&adapter->dev); |
| 487 | put_device(&adapter->dev); |
| 488 | } |
| 489 | |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 490 | break; |
| 491 | } |
| 492 | |
| 493 | return NOTIFY_OK; |
| 494 | } |
| 495 | |
| 496 | struct notifier_block i2c_acpi_notifier = { |
| 497 | .notifier_call = i2c_acpi_notify, |
| 498 | }; |
| 499 | |
| 500 | /** |
Hans de Goede | c537be0 | 2021-12-03 11:28:46 +0100 | [diff] [blame] | 501 | * i2c_acpi_new_device_by_fwnode - Create i2c-client for the Nth I2cSerialBus resource |
| 502 | * @fwnode: fwnode with the ACPI resources to get the client from |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 503 | * @index: Index of ACPI resource to get |
| 504 | * @info: describes the I2C device; note this is modified (addr gets set) |
| 505 | * Context: can sleep |
| 506 | * |
| 507 | * By default the i2c subsys creates an i2c-client for the first I2cSerialBus |
| 508 | * resource of an acpi_device, but some acpi_devices have multiple I2cSerialBus |
| 509 | * resources, in that case this function can be used to create an i2c-client |
| 510 | * for other I2cSerialBus resources in the Current Resource Settings table. |
| 511 | * |
Wolfram Sang | 90a3be9 | 2020-01-07 18:47:42 +0100 | [diff] [blame] | 512 | * Also see i2c_new_client_device, which this function calls to create the |
| 513 | * i2c-client. |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 514 | * |
Andy Shevchenko | 2dea645 | 2018-11-28 13:45:25 +0200 | [diff] [blame] | 515 | * Returns a pointer to the new i2c-client, or error pointer in case of failure. |
| 516 | * Specifically, -EPROBE_DEFER is returned if the adapter is not found. |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 517 | */ |
Hans de Goede | c537be0 | 2021-12-03 11:28:46 +0100 | [diff] [blame] | 518 | struct i2c_client *i2c_acpi_new_device_by_fwnode(struct fwnode_handle *fwnode, |
| 519 | int index, |
| 520 | struct i2c_board_info *info) |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 521 | { |
| 522 | struct i2c_acpi_lookup lookup; |
| 523 | struct i2c_adapter *adapter; |
Hans de Goede | c537be0 | 2021-12-03 11:28:46 +0100 | [diff] [blame] | 524 | struct acpi_device *adev; |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 525 | LIST_HEAD(resource_list); |
| 526 | int ret; |
| 527 | |
Hans de Goede | c537be0 | 2021-12-03 11:28:46 +0100 | [diff] [blame] | 528 | adev = to_acpi_device_node(fwnode); |
| 529 | if (!adev) |
| 530 | return ERR_PTR(-ENODEV); |
| 531 | |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 532 | memset(&lookup, 0, sizeof(lookup)); |
| 533 | lookup.info = info; |
| 534 | lookup.device_handle = acpi_device_handle(adev); |
| 535 | lookup.index = index; |
| 536 | |
| 537 | ret = acpi_dev_get_resources(adev, &resource_list, |
| 538 | i2c_acpi_fill_info, &lookup); |
Andy Shevchenko | 2dea645 | 2018-11-28 13:45:25 +0200 | [diff] [blame] | 539 | if (ret < 0) |
| 540 | return ERR_PTR(ret); |
| 541 | |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 542 | acpi_dev_free_resource_list(&resource_list); |
| 543 | |
Andy Shevchenko | 2dea645 | 2018-11-28 13:45:25 +0200 | [diff] [blame] | 544 | if (!info->addr) |
| 545 | return ERR_PTR(-EADDRNOTAVAIL); |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 546 | |
| 547 | adapter = i2c_acpi_find_adapter_by_handle(lookup.adapter_handle); |
| 548 | if (!adapter) |
Andy Shevchenko | 2dea645 | 2018-11-28 13:45:25 +0200 | [diff] [blame] | 549 | return ERR_PTR(-EPROBE_DEFER); |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 550 | |
Wolfram Sang | 90a3be9 | 2020-01-07 18:47:42 +0100 | [diff] [blame] | 551 | return i2c_new_client_device(adapter, info); |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 552 | } |
Hans de Goede | c537be0 | 2021-12-03 11:28:46 +0100 | [diff] [blame] | 553 | EXPORT_SYMBOL_GPL(i2c_acpi_new_device_by_fwnode); |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 554 | |
Sakari Ailus | b18c1ad | 2021-10-18 15:17:25 +0300 | [diff] [blame] | 555 | bool i2c_acpi_waive_d0_probe(struct device *dev) |
| 556 | { |
| 557 | struct i2c_driver *driver = to_i2c_driver(dev->driver); |
| 558 | struct acpi_device *adev = ACPI_COMPANION(dev); |
| 559 | |
| 560 | return driver->flags & I2C_DRV_ACPI_WAIVE_D0_PROBE && |
| 561 | adev && adev->power.state_for_enumeration >= adev->power.state; |
| 562 | } |
| 563 | EXPORT_SYMBOL_GPL(i2c_acpi_waive_d0_probe); |
| 564 | |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 565 | #ifdef CONFIG_ACPI_I2C_OPREGION |
| 566 | static int acpi_gsb_i2c_read_bytes(struct i2c_client *client, |
| 567 | u8 cmd, u8 *data, u8 data_len) |
| 568 | { |
| 569 | |
| 570 | struct i2c_msg msgs[2]; |
| 571 | int ret; |
| 572 | u8 *buffer; |
| 573 | |
| 574 | buffer = kzalloc(data_len, GFP_KERNEL); |
| 575 | if (!buffer) |
| 576 | return AE_NO_MEMORY; |
| 577 | |
| 578 | msgs[0].addr = client->addr; |
| 579 | msgs[0].flags = client->flags; |
| 580 | msgs[0].len = 1; |
| 581 | msgs[0].buf = &cmd; |
| 582 | |
| 583 | msgs[1].addr = client->addr; |
| 584 | msgs[1].flags = client->flags | I2C_M_RD; |
| 585 | msgs[1].len = data_len; |
| 586 | msgs[1].buf = buffer; |
| 587 | |
| 588 | ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); |
Hans de Goede | 7781eda | 2018-04-22 19:58:00 +0200 | [diff] [blame] | 589 | if (ret < 0) { |
| 590 | /* Getting a NACK is unfortunately normal with some DSTDs */ |
| 591 | if (ret == -EREMOTEIO) |
| 592 | dev_dbg(&client->adapter->dev, "i2c read %d bytes from client@%#x starting at reg %#x failed, error: %d\n", |
| 593 | data_len, client->addr, cmd, ret); |
| 594 | else |
| 595 | dev_err(&client->adapter->dev, "i2c read %d bytes from client@%#x starting at reg %#x failed, error: %d\n", |
| 596 | data_len, client->addr, cmd, ret); |
Hans de Goede | 0a30446 | 2018-08-12 12:53:21 +0200 | [diff] [blame] | 597 | /* 2 transfers must have completed successfully */ |
| 598 | } else if (ret == 2) { |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 599 | memcpy(data, buffer, data_len); |
Hans de Goede | 0a30446 | 2018-08-12 12:53:21 +0200 | [diff] [blame] | 600 | ret = 0; |
| 601 | } else { |
| 602 | ret = -EIO; |
Hans de Goede | 7781eda | 2018-04-22 19:58:00 +0200 | [diff] [blame] | 603 | } |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 604 | |
| 605 | kfree(buffer); |
| 606 | return ret; |
| 607 | } |
| 608 | |
| 609 | static int acpi_gsb_i2c_write_bytes(struct i2c_client *client, |
| 610 | u8 cmd, u8 *data, u8 data_len) |
| 611 | { |
| 612 | |
| 613 | struct i2c_msg msgs[1]; |
| 614 | u8 *buffer; |
| 615 | int ret = AE_OK; |
| 616 | |
| 617 | buffer = kzalloc(data_len + 1, GFP_KERNEL); |
| 618 | if (!buffer) |
| 619 | return AE_NO_MEMORY; |
| 620 | |
| 621 | buffer[0] = cmd; |
| 622 | memcpy(buffer + 1, data, data_len); |
| 623 | |
| 624 | msgs[0].addr = client->addr; |
| 625 | msgs[0].flags = client->flags; |
| 626 | msgs[0].len = data_len + 1; |
| 627 | msgs[0].buf = buffer; |
| 628 | |
| 629 | ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 630 | |
| 631 | kfree(buffer); |
Hans de Goede | c463a15 | 2018-08-12 12:53:20 +0200 | [diff] [blame] | 632 | |
| 633 | if (ret < 0) { |
| 634 | dev_err(&client->adapter->dev, "i2c write failed: %d\n", ret); |
| 635 | return ret; |
| 636 | } |
| 637 | |
| 638 | /* 1 transfer must have completed successfully */ |
| 639 | return (ret == 1) ? 0 : -EIO; |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 640 | } |
| 641 | |
| 642 | static acpi_status |
| 643 | i2c_acpi_space_handler(u32 function, acpi_physical_address command, |
| 644 | u32 bits, u64 *value64, |
| 645 | void *handler_context, void *region_context) |
| 646 | { |
| 647 | struct gsb_buffer *gsb = (struct gsb_buffer *)value64; |
| 648 | struct i2c_acpi_handler_data *data = handler_context; |
| 649 | struct acpi_connection_info *info = &data->info; |
| 650 | struct acpi_resource_i2c_serialbus *sb; |
| 651 | struct i2c_adapter *adapter = data->adapter; |
| 652 | struct i2c_client *client; |
| 653 | struct acpi_resource *ares; |
| 654 | u32 accessor_type = function >> 16; |
| 655 | u8 action = function & ACPI_IO_MASK; |
| 656 | acpi_status ret; |
| 657 | int status; |
| 658 | |
| 659 | ret = acpi_buffer_to_resource(info->connection, info->length, &ares); |
| 660 | if (ACPI_FAILURE(ret)) |
| 661 | return ret; |
| 662 | |
| 663 | client = kzalloc(sizeof(*client), GFP_KERNEL); |
| 664 | if (!client) { |
| 665 | ret = AE_NO_MEMORY; |
| 666 | goto err; |
| 667 | } |
| 668 | |
Andy Shevchenko | 0d5102f | 2018-11-28 13:45:29 +0200 | [diff] [blame] | 669 | if (!value64 || !i2c_acpi_get_i2c_resource(ares, &sb)) { |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 670 | ret = AE_BAD_PARAMETER; |
| 671 | goto err; |
| 672 | } |
| 673 | |
| 674 | client->adapter = adapter; |
| 675 | client->addr = sb->slave_address; |
| 676 | |
| 677 | if (sb->access_mode == ACPI_I2C_10BIT_MODE) |
| 678 | client->flags |= I2C_CLIENT_TEN; |
| 679 | |
| 680 | switch (accessor_type) { |
| 681 | case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV: |
| 682 | if (action == ACPI_READ) { |
| 683 | status = i2c_smbus_read_byte(client); |
| 684 | if (status >= 0) { |
| 685 | gsb->bdata = status; |
| 686 | status = 0; |
| 687 | } |
| 688 | } else { |
| 689 | status = i2c_smbus_write_byte(client, gsb->bdata); |
| 690 | } |
| 691 | break; |
| 692 | |
| 693 | case ACPI_GSB_ACCESS_ATTRIB_BYTE: |
| 694 | if (action == ACPI_READ) { |
| 695 | status = i2c_smbus_read_byte_data(client, command); |
| 696 | if (status >= 0) { |
| 697 | gsb->bdata = status; |
| 698 | status = 0; |
| 699 | } |
| 700 | } else { |
| 701 | status = i2c_smbus_write_byte_data(client, command, |
| 702 | gsb->bdata); |
| 703 | } |
| 704 | break; |
| 705 | |
| 706 | case ACPI_GSB_ACCESS_ATTRIB_WORD: |
| 707 | if (action == ACPI_READ) { |
| 708 | status = i2c_smbus_read_word_data(client, command); |
| 709 | if (status >= 0) { |
| 710 | gsb->wdata = status; |
| 711 | status = 0; |
| 712 | } |
| 713 | } else { |
| 714 | status = i2c_smbus_write_word_data(client, command, |
| 715 | gsb->wdata); |
| 716 | } |
| 717 | break; |
| 718 | |
| 719 | case ACPI_GSB_ACCESS_ATTRIB_BLOCK: |
| 720 | if (action == ACPI_READ) { |
| 721 | status = i2c_smbus_read_block_data(client, command, |
| 722 | gsb->data); |
| 723 | if (status >= 0) { |
| 724 | gsb->len = status; |
| 725 | status = 0; |
| 726 | } |
| 727 | } else { |
| 728 | status = i2c_smbus_write_block_data(client, command, |
| 729 | gsb->len, gsb->data); |
| 730 | } |
| 731 | break; |
| 732 | |
| 733 | case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE: |
| 734 | if (action == ACPI_READ) { |
| 735 | status = acpi_gsb_i2c_read_bytes(client, command, |
| 736 | gsb->data, info->access_length); |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 737 | } else { |
| 738 | status = acpi_gsb_i2c_write_bytes(client, command, |
| 739 | gsb->data, info->access_length); |
| 740 | } |
| 741 | break; |
| 742 | |
| 743 | default: |
| 744 | dev_warn(&adapter->dev, "protocol 0x%02x not supported for client 0x%02x\n", |
| 745 | accessor_type, client->addr); |
| 746 | ret = AE_BAD_PARAMETER; |
| 747 | goto err; |
| 748 | } |
| 749 | |
| 750 | gsb->status = status; |
| 751 | |
| 752 | err: |
| 753 | kfree(client); |
| 754 | ACPI_FREE(ares); |
| 755 | return ret; |
| 756 | } |
| 757 | |
| 758 | |
| 759 | int i2c_acpi_install_space_handler(struct i2c_adapter *adapter) |
| 760 | { |
| 761 | acpi_handle handle; |
| 762 | struct i2c_acpi_handler_data *data; |
| 763 | acpi_status status; |
| 764 | |
| 765 | if (!adapter->dev.parent) |
| 766 | return -ENODEV; |
| 767 | |
| 768 | handle = ACPI_HANDLE(adapter->dev.parent); |
| 769 | |
| 770 | if (!handle) |
| 771 | return -ENODEV; |
| 772 | |
| 773 | data = kzalloc(sizeof(struct i2c_acpi_handler_data), |
| 774 | GFP_KERNEL); |
| 775 | if (!data) |
| 776 | return -ENOMEM; |
| 777 | |
| 778 | data->adapter = adapter; |
| 779 | status = acpi_bus_attach_private_data(handle, (void *)data); |
| 780 | if (ACPI_FAILURE(status)) { |
| 781 | kfree(data); |
| 782 | return -ENOMEM; |
| 783 | } |
| 784 | |
| 785 | status = acpi_install_address_space_handler(handle, |
| 786 | ACPI_ADR_SPACE_GSBUS, |
| 787 | &i2c_acpi_space_handler, |
| 788 | NULL, |
| 789 | data); |
| 790 | if (ACPI_FAILURE(status)) { |
| 791 | dev_err(&adapter->dev, "Error installing i2c space handler\n"); |
| 792 | acpi_bus_detach_private_data(handle); |
| 793 | kfree(data); |
| 794 | return -ENOMEM; |
| 795 | } |
| 796 | |
Wolfram Sang | 53f8f7c | 2017-05-23 16:22:23 +0200 | [diff] [blame] | 797 | return 0; |
| 798 | } |
| 799 | |
| 800 | void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter) |
| 801 | { |
| 802 | acpi_handle handle; |
| 803 | struct i2c_acpi_handler_data *data; |
| 804 | acpi_status status; |
| 805 | |
| 806 | if (!adapter->dev.parent) |
| 807 | return; |
| 808 | |
| 809 | handle = ACPI_HANDLE(adapter->dev.parent); |
| 810 | |
| 811 | if (!handle) |
| 812 | return; |
| 813 | |
| 814 | acpi_remove_address_space_handler(handle, |
| 815 | ACPI_ADR_SPACE_GSBUS, |
| 816 | &i2c_acpi_space_handler); |
| 817 | |
| 818 | status = acpi_bus_get_private_data(handle, (void **)&data); |
| 819 | if (ACPI_SUCCESS(status)) |
| 820 | kfree(data); |
| 821 | |
| 822 | acpi_bus_detach_private_data(handle); |
| 823 | } |
| 824 | #endif /* CONFIG_ACPI_I2C_OPREGION */ |