input/misc/soc_button_array.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * Supports for the button array on SoC tablets originally running
0004  * Windows 8.
0005  *
0006  * (C) Copyright 2014 Intel Corporation
0007  */
0008
0009 #include <linux/module.h>
0010 #include <linux/input.h>
0011 #include <linux/init.h>
0012 #include <linux/irq.h>
0013 #include <linux/kernel.h>
0014 #include <linux/acpi.h>
0015 #include <linux/dmi.h>
0016 #include <linux/gpio/consumer.h>
0017 #include <linux/gpio_keys.h>
0018 #include <linux/gpio.h>
0019 #include <linux/platform_device.h>
0020
0021 struct soc_button_info {
0022     const char *name;
0023     int acpi_index;
0024     unsigned int event_type;
0025     unsigned int event_code;
0026     bool autorepeat;
0027     bool wakeup;
0028     bool active_low;
0029 };
0030
0031 struct soc_device_data {
0032     const struct soc_button_info *button_info;
0033     int (*check)(struct device *dev);
0034 };
0035
0036 /*
0037  * Some of the buttons like volume up/down are auto repeat, while others
0038  * are not. To support both, we register two platform devices, and put
0039  * buttons into them based on whether the key should be auto repeat.
0040  */
0041 #define BUTTON_TYPES    2
0042
0043 struct soc_button_data {
0044     struct platform_device *children[BUTTON_TYPES];
0045 };
0046
0047 /*
0048  * Some 2-in-1s which use the soc_button_array driver have this ugly issue in
0049  * their DSDT where the _LID method modifies the irq-type settings of the GPIOs
0050  * used for the power and home buttons. The intend of this AML code is to
0051  * disable these buttons when the lid is closed.
0052  * The AML does this by directly poking the GPIO controllers registers. This is
0053  * problematic because when re-enabling the irq, which happens whenever _LID
0054  * gets called with the lid open (e.g. on boot and on resume), it sets the
0055  * irq-type to IRQ_TYPE_LEVEL_LOW. Where as the gpio-keys driver programs the
0056  * type to, and expects it to be, IRQ_TYPE_EDGE_BOTH.
0057  * To work around this we don't set gpio_keys_button.gpio on these 2-in-1s,
0058  * instead we get the irq for the GPIO ourselves, configure it as
0059  * IRQ_TYPE_LEVEL_LOW (to match how the _LID AML code configures it) and pass
0060  * the irq in gpio_keys_button.irq. Below is a list of affected devices.
0061  */
0062 static const struct dmi_system_id dmi_use_low_level_irq[] = {
0063     {
0064         /*
0065          * Acer Switch 10 SW5-012. _LID method messes with home- and
0066          * power-button GPIO IRQ settings. When (re-)enabling the irq
0067          * it ors in its own flags without clearing the previous set
0068          * ones, leading to an irq-type of IRQ_TYPE_LEVEL_LOW |
0069          * IRQ_TYPE_LEVEL_HIGH causing a continuous interrupt storm.
0070          */
0071         .matches = {
0072             DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
0073             DMI_MATCH(DMI_PRODUCT_NAME, "Aspire SW5-012"),
0074         },
0075     },
0076     {
0077         /*
0078          * Acer One S1003. _LID method messes with power-button GPIO
0079          * IRQ settings, leading to a non working power-button.
0080          */
0081         .matches = {
0082             DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
0083             DMI_MATCH(DMI_PRODUCT_NAME, "One S1003"),
0084         },
0085     },
0086     {
0087         /*
0088          * Lenovo Yoga Tab2 1051F/1051L, something messes with the home-button
0089          * IRQ settings, leading to a non working home-button.
0090          */
0091         .matches = {
0092             DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
0093             DMI_MATCH(DMI_PRODUCT_NAME, "60073"),
0094             DMI_MATCH(DMI_PRODUCT_VERSION, "1051"),
0095         },
0096     },
0097     {} /* Terminating entry */
0098 };
0099
0100 /*
0101  * Get the Nth GPIO number from the ACPI object.
0102  */
0103 static int soc_button_lookup_gpio(struct device *dev, int acpi_index,
0104                   int *gpio_ret, int *irq_ret)
0105 {
0106     struct gpio_desc *desc;
0107
0108     desc = gpiod_get_index(dev, NULL, acpi_index, GPIOD_ASIS);
0109     if (IS_ERR(desc))
0110         return PTR_ERR(desc);
0111
0112     *gpio_ret = desc_to_gpio(desc);
0113     *irq_ret = gpiod_to_irq(desc);
0114
0115     gpiod_put(desc);
0116
0117     return 0;
0118 }
0119
0120 static struct platform_device *
0121 soc_button_device_create(struct platform_device *pdev,
0122              const struct soc_button_info *button_info,
0123              bool autorepeat)
0124 {
0125     const struct soc_button_info *info;
0126     struct platform_device *pd;
0127     struct gpio_keys_button *gpio_keys;
0128     struct gpio_keys_platform_data *gpio_keys_pdata;
0129     int error, gpio, irq;
0130     int n_buttons = 0;
0131
0132     for (info = button_info; info->name; info++)
0133         if (info->autorepeat == autorepeat)
0134             n_buttons++;
0135
0136     gpio_keys_pdata = devm_kzalloc(&pdev->dev,
0137                        sizeof(*gpio_keys_pdata) +
0138                     sizeof(*gpio_keys) * n_buttons,
0139                        GFP_KERNEL);
0140     if (!gpio_keys_pdata)
0141         return ERR_PTR(-ENOMEM);
0142
0143     gpio_keys = (void *)(gpio_keys_pdata + 1);
0144     n_buttons = 0;
0145
0146     for (info = button_info; info->name; info++) {
0147         if (info->autorepeat != autorepeat)
0148             continue;
0149
0150         error = soc_button_lookup_gpio(&pdev->dev, info->acpi_index, &gpio, &irq);
0151         if (error || irq < 0) {
0152             /*
0153              * Skip GPIO if not present. Note we deliberately
0154              * ignore -EPROBE_DEFER errors here. On some devices
0155              * Intel is using so called virtual GPIOs which are not
0156              * GPIOs at all but some way for AML code to check some
0157              * random status bits without need a custom opregion.
0158              * In some cases the resources table we parse points to
0159              * such a virtual GPIO, since these are not real GPIOs
0160              * we do not have a driver for these so they will never
0161              * show up, therefore we ignore -EPROBE_DEFER.
0162              */
0163             continue;
0164         }
0165
0166         /* See dmi_use_low_level_irq[] comment */
0167         if (!autorepeat && dmi_check_system(dmi_use_low_level_irq)) {
0168             irq_set_irq_type(irq, IRQ_TYPE_LEVEL_LOW);
0169             gpio_keys[n_buttons].irq = irq;
0170             gpio_keys[n_buttons].gpio = -ENOENT;
0171         } else {
0172             gpio_keys[n_buttons].gpio = gpio;
0173         }
0174
0175         gpio_keys[n_buttons].type = info->event_type;
0176         gpio_keys[n_buttons].code = info->event_code;
0177         gpio_keys[n_buttons].active_low = info->active_low;
0178         gpio_keys[n_buttons].desc = info->name;
0179         gpio_keys[n_buttons].wakeup = info->wakeup;
0180         /* These devices often use cheap buttons, use 50 ms debounce */
0181         gpio_keys[n_buttons].debounce_interval = 50;
0182         n_buttons++;
0183     }
0184
0185     if (n_buttons == 0) {
0186         error = -ENODEV;
0187         goto err_free_mem;
0188     }
0189
0190     gpio_keys_pdata->buttons = gpio_keys;
0191     gpio_keys_pdata->nbuttons = n_buttons;
0192     gpio_keys_pdata->rep = autorepeat;
0193
0194     pd = platform_device_register_resndata(&pdev->dev, "gpio-keys",
0195                            PLATFORM_DEVID_AUTO, NULL, 0,
0196                            gpio_keys_pdata,
0197                            sizeof(*gpio_keys_pdata));
0198     error = PTR_ERR_OR_ZERO(pd);
0199     if (error) {
0200         dev_err(&pdev->dev,
0201             "failed registering gpio-keys: %d\n", error);
0202         goto err_free_mem;
0203     }
0204
0205     return pd;
0206
0207 err_free_mem:
0208     devm_kfree(&pdev->dev, gpio_keys_pdata);
0209     return ERR_PTR(error);
0210 }
0211
0212 static int soc_button_get_acpi_object_int(const union acpi_object *obj)
0213 {
0214     if (obj->type != ACPI_TYPE_INTEGER)
0215         return -1;
0216
0217     return obj->integer.value;
0218 }
0219
0220 /* Parse a single ACPI0011 _DSD button descriptor */
0221 static int soc_button_parse_btn_desc(struct device *dev,
0222                      const union acpi_object *desc,
0223                      int collection_uid,
0224                      struct soc_button_info *info)
0225 {
0226     int upage, usage;
0227
0228     if (desc->type != ACPI_TYPE_PACKAGE ||
0229         desc->package.count != 5 ||
0230         /* First byte should be 1 (control) */
0231         soc_button_get_acpi_object_int(&desc->package.elements[0]) != 1 ||
0232         /* Third byte should be collection uid */
0233         soc_button_get_acpi_object_int(&desc->package.elements[2]) !=
0234                                 collection_uid) {
0235         dev_err(dev, "Invalid ACPI Button Descriptor\n");
0236         return -ENODEV;
0237     }
0238
0239     info->event_type = EV_KEY;
0240     info->active_low = true;
0241     info->acpi_index =
0242         soc_button_get_acpi_object_int(&desc->package.elements[1]);
0243     upage = soc_button_get_acpi_object_int(&desc->package.elements[3]);
0244     usage = soc_button_get_acpi_object_int(&desc->package.elements[4]);
0245
0246     /*
0247      * The UUID: fa6bd625-9ce8-470d-a2c7-b3ca36c4282e descriptors use HID
0248      * usage page and usage codes, but otherwise the device is not HID
0249      * compliant: it uses one irq per button instead of generating HID
0250      * input reports and some buttons should generate wakeups where as
0251      * others should not, so we cannot use the HID subsystem.
0252      *
0253      * Luckily all devices only use a few usage page + usage combinations,
0254      * so we can simply check for the known combinations here.
0255      */
0256     if (upage == 0x01 && usage == 0x81) {
0257         info->name = "power";
0258         info->event_code = KEY_POWER;
0259         info->wakeup = true;
0260     } else if (upage == 0x01 && usage == 0xca) {
0261         info->name = "rotation lock switch";
0262         info->event_type = EV_SW;
0263         info->event_code = SW_ROTATE_LOCK;
0264     } else if (upage == 0x07 && usage == 0xe3) {
0265         info->name = "home";
0266         info->event_code = KEY_LEFTMETA;
0267         info->wakeup = true;
0268     } else if (upage == 0x0c && usage == 0xe9) {
0269         info->name = "volume_up";
0270         info->event_code = KEY_VOLUMEUP;
0271         info->autorepeat = true;
0272     } else if (upage == 0x0c && usage == 0xea) {
0273         info->name = "volume_down";
0274         info->event_code = KEY_VOLUMEDOWN;
0275         info->autorepeat = true;
0276     } else {
0277         dev_warn(dev, "Unknown button index %d upage %02x usage %02x, ignoring\n",
0278              info->acpi_index, upage, usage);
0279         info->name = "unknown";
0280         info->event_code = KEY_RESERVED;
0281     }
0282
0283     return 0;
0284 }
0285
0286 /* ACPI0011 _DSD btns descriptors UUID: fa6bd625-9ce8-470d-a2c7-b3ca36c4282e */
0287 static const u8 btns_desc_uuid[16] = {
0288     0x25, 0xd6, 0x6b, 0xfa, 0xe8, 0x9c, 0x0d, 0x47,
0289     0xa2, 0xc7, 0xb3, 0xca, 0x36, 0xc4, 0x28, 0x2e
0290 };
0291
0292 /* Parse ACPI0011 _DSD button descriptors */
0293 static struct soc_button_info *soc_button_get_button_info(struct device *dev)
0294 {
0295     struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
0296     const union acpi_object *desc, *el0, *uuid, *btns_desc = NULL;
0297     struct soc_button_info *button_info;
0298     acpi_status status;
0299     int i, btn, collection_uid = -1;
0300
0301     status = acpi_evaluate_object_typed(ACPI_HANDLE(dev), "_DSD", NULL,
0302                         &buf, ACPI_TYPE_PACKAGE);
0303     if (ACPI_FAILURE(status)) {
0304         dev_err(dev, "ACPI _DSD object not found\n");
0305         return ERR_PTR(-ENODEV);
0306     }
0307
0308     /* Look for the Button Descriptors UUID */
0309     desc = buf.pointer;
0310     for (i = 0; (i + 1) < desc->package.count; i += 2) {
0311         uuid = &desc->package.elements[i];
0312
0313         if (uuid->type != ACPI_TYPE_BUFFER ||
0314             uuid->buffer.length != 16 ||
0315             desc->package.elements[i + 1].type != ACPI_TYPE_PACKAGE) {
0316             break;
0317         }
0318
0319         if (memcmp(uuid->buffer.pointer, btns_desc_uuid, 16) == 0) {
0320             btns_desc = &desc->package.elements[i + 1];
0321             break;
0322         }
0323     }
0324
0325     if (!btns_desc) {
0326         dev_err(dev, "ACPI Button Descriptors not found\n");
0327         button_info = ERR_PTR(-ENODEV);
0328         goto out;
0329     }
0330
0331     /* The first package describes the collection */
0332     el0 = &btns_desc->package.elements[0];
0333     if (el0->type == ACPI_TYPE_PACKAGE &&
0334         el0->package.count == 5 &&
0335         /* First byte should be 0 (collection) */
0336         soc_button_get_acpi_object_int(&el0->package.elements[0]) == 0 &&
0337         /* Third byte should be 0 (top level collection) */
0338         soc_button_get_acpi_object_int(&el0->package.elements[2]) == 0) {
0339         collection_uid = soc_button_get_acpi_object_int(
0340                         &el0->package.elements[1]);
0341     }
0342     if (collection_uid == -1) {
0343         dev_err(dev, "Invalid Button Collection Descriptor\n");
0344         button_info = ERR_PTR(-ENODEV);
0345         goto out;
0346     }
0347
0348     /* There are package.count - 1 buttons + 1 terminating empty entry */
0349     button_info = devm_kcalloc(dev, btns_desc->package.count,
0350                    sizeof(*button_info), GFP_KERNEL);
0351     if (!button_info) {
0352         button_info = ERR_PTR(-ENOMEM);
0353         goto out;
0354     }
0355
0356     /* Parse the button descriptors */
0357     for (i = 1, btn = 0; i < btns_desc->package.count; i++, btn++) {
0358         if (soc_button_parse_btn_desc(dev,
0359                           &btns_desc->package.elements[i],
0360                           collection_uid,
0361                           &button_info[btn])) {
0362             button_info = ERR_PTR(-ENODEV);
0363             goto out;
0364         }
0365     }
0366
0367 out:
0368     kfree(buf.pointer);
0369     return button_info;
0370 }
0371
0372 static int soc_button_remove(struct platform_device *pdev)
0373 {
0374     struct soc_button_data *priv = platform_get_drvdata(pdev);
0375
0376     int i;
0377
0378     for (i = 0; i < BUTTON_TYPES; i++)
0379         if (priv->children[i])
0380             platform_device_unregister(priv->children[i]);
0381
0382     return 0;
0383 }
0384
0385 static int soc_button_probe(struct platform_device *pdev)
0386 {
0387     struct device *dev = &pdev->dev;
0388     const struct soc_device_data *device_data;
0389     const struct soc_button_info *button_info;
0390     struct soc_button_data *priv;
0391     struct platform_device *pd;
0392     int i;
0393     int error;
0394
0395     device_data = acpi_device_get_match_data(dev);
0396     if (device_data && device_data->check) {
0397         error = device_data->check(dev);
0398         if (error)
0399             return error;
0400     }
0401
0402     if (device_data && device_data->button_info) {
0403         button_info = device_data->button_info;
0404     } else {
0405         button_info = soc_button_get_button_info(dev);
0406         if (IS_ERR(button_info))
0407             return PTR_ERR(button_info);
0408     }
0409
0410     error = gpiod_count(dev, NULL);
0411     if (error < 0) {
0412         dev_dbg(dev, "no GPIO attached, ignoring...\n");
0413         return -ENODEV;
0414     }
0415
0416     priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
0417     if (!priv)
0418         return -ENOMEM;
0419
0420     platform_set_drvdata(pdev, priv);
0421
0422     for (i = 0; i < BUTTON_TYPES; i++) {
0423         pd = soc_button_device_create(pdev, button_info, i == 0);
0424         if (IS_ERR(pd)) {
0425             error = PTR_ERR(pd);
0426             if (error != -ENODEV) {
0427                 soc_button_remove(pdev);
0428                 return error;
0429             }
0430             continue;
0431         }
0432
0433         priv->children[i] = pd;
0434     }
0435
0436     if (!priv->children[0] && !priv->children[1])
0437         return -ENODEV;
0438
0439     if (!device_data || !device_data->button_info)
0440         devm_kfree(dev, button_info);
0441
0442     return 0;
0443 }
0444
0445 /*
0446  * Definition of buttons on the tablet. The ACPI index of each button
0447  * is defined in section 2.8.7.2 of "Windows ACPI Design Guide for SoC
0448  * Platforms"
0449  */
0450 static const struct soc_button_info soc_button_PNP0C40[] = {
0451     { "power", 0, EV_KEY, KEY_POWER, false, true, true },
0452     { "home", 1, EV_KEY, KEY_LEFTMETA, false, true, true },
0453     { "volume_up", 2, EV_KEY, KEY_VOLUMEUP, true, false, true },
0454     { "volume_down", 3, EV_KEY, KEY_VOLUMEDOWN, true, false, true },
0455     { "rotation_lock", 4, EV_KEY, KEY_ROTATE_LOCK_TOGGLE, false, false, true },
0456     { }
0457 };
0458
0459 static const struct soc_device_data soc_device_PNP0C40 = {
0460     .button_info = soc_button_PNP0C40,
0461 };
0462
0463 static const struct soc_button_info soc_button_INT33D3[] = {
0464     { "tablet_mode", 0, EV_SW, SW_TABLET_MODE, false, false, false },
0465     { }
0466 };
0467
0468 static const struct soc_device_data soc_device_INT33D3 = {
0469     .button_info = soc_button_INT33D3,
0470 };
0471
0472 /*
0473  * Button info for Microsoft Surface 3 (non pro), this is indentical to
0474  * the PNP0C40 info except that the home button is active-high.
0475  *
0476  * The Surface 3 Pro also has a MSHW0028 ACPI device, but that uses a custom
0477  * version of the drivers/platform/x86/intel/hid.c 5 button array ACPI API
0478  * instead. A check() callback is not necessary though as the Surface 3 Pro
0479  * MSHW0028 ACPI device's resource table does not contain any GPIOs.
0480  */
0481 static const struct soc_button_info soc_button_MSHW0028[] = {
0482     { "power", 0, EV_KEY, KEY_POWER, false, true, true },
0483     { "home", 1, EV_KEY, KEY_LEFTMETA, false, true, false },
0484     { "volume_up", 2, EV_KEY, KEY_VOLUMEUP, true, false, true },
0485     { "volume_down", 3, EV_KEY, KEY_VOLUMEDOWN, true, false, true },
0486     { }
0487 };
0488
0489 static const struct soc_device_data soc_device_MSHW0028 = {
0490     .button_info = soc_button_MSHW0028,
0491 };
0492
0493 /*
0494  * Special device check for Surface Book 2 and Surface Pro (2017).
0495  * Both, the Surface Pro 4 (surfacepro3_button.c) and the above mentioned
0496  * devices use MSHW0040 for power and volume buttons, however the way they
0497  * have to be addressed differs. Make sure that we only load this drivers
0498  * for the correct devices by checking the OEM Platform Revision provided by
0499  * the _DSM method.
0500  */
0501 #define MSHW0040_DSM_REVISION       0x01
0502 #define MSHW0040_DSM_GET_OMPR       0x02    // get OEM Platform Revision
0503 static const guid_t MSHW0040_DSM_UUID =
0504     GUID_INIT(0x6fd05c69, 0xcde3, 0x49f4, 0x95, 0xed, 0xab, 0x16, 0x65,
0505           0x49, 0x80, 0x35);
0506
0507 static int soc_device_check_MSHW0040(struct device *dev)
0508 {
0509     acpi_handle handle = ACPI_HANDLE(dev);
0510     union acpi_object *result;
0511     u64 oem_platform_rev = 0;   // valid revisions are nonzero
0512
0513     // get OEM platform revision
0514     result = acpi_evaluate_dsm_typed(handle, &MSHW0040_DSM_UUID,
0515                      MSHW0040_DSM_REVISION,
0516                      MSHW0040_DSM_GET_OMPR, NULL,
0517                      ACPI_TYPE_INTEGER);
0518
0519     if (result) {
0520         oem_platform_rev = result->integer.value;
0521         ACPI_FREE(result);
0522     }
0523
0524     /*
0525      * If the revision is zero here, the _DSM evaluation has failed. This
0526      * indicates that we have a Pro 4 or Book 1 and this driver should not
0527      * be used.
0528      */
0529     if (oem_platform_rev == 0)
0530         return -ENODEV;
0531
0532     dev_dbg(dev, "OEM Platform Revision %llu\n", oem_platform_rev);
0533
0534     return 0;
0535 }
0536
0537 /*
0538  * Button infos for Microsoft Surface Book 2 and Surface Pro (2017).
0539  * Obtained from DSDT/testing.
0540  */
0541 static const struct soc_button_info soc_button_MSHW0040[] = {
0542     { "power", 0, EV_KEY, KEY_POWER, false, true, true },
0543     { "volume_up", 2, EV_KEY, KEY_VOLUMEUP, true, false, true },
0544     { "volume_down", 4, EV_KEY, KEY_VOLUMEDOWN, true, false, true },
0545     { }
0546 };
0547
0548 static const struct soc_device_data soc_device_MSHW0040 = {
0549     .button_info = soc_button_MSHW0040,
0550     .check = soc_device_check_MSHW0040,
0551 };
0552
0553 static const struct acpi_device_id soc_button_acpi_match[] = {
0554     { "PNP0C40", (unsigned long)&soc_device_PNP0C40 },
0555     { "INT33D3", (unsigned long)&soc_device_INT33D3 },
0556     { "ID9001", (unsigned long)&soc_device_INT33D3 },
0557     { "ACPI0011", 0 },
0558
0559     /* Microsoft Surface Devices (3th, 5th and 6th generation) */
0560     { "MSHW0028", (unsigned long)&soc_device_MSHW0028 },
0561     { "MSHW0040", (unsigned long)&soc_device_MSHW0040 },
0562
0563     { }
0564 };
0565
0566 MODULE_DEVICE_TABLE(acpi, soc_button_acpi_match);
0567
0568 static struct platform_driver soc_button_driver = {
0569     .probe          = soc_button_probe,
0570     .remove     = soc_button_remove,
0571     .driver     = {
0572         .name = KBUILD_MODNAME,
0573         .acpi_match_table = ACPI_PTR(soc_button_acpi_match),
0574     },
0575 };
0576 module_platform_driver(soc_button_driver);
0577
0578 MODULE_LICENSE("GPL");