drivers/platform/x86/intel_cht_int33fe.c

   1 /*
   2  * Intel Cherry Trail ACPI INT33FE pseudo device driver
   3  *
   4  * Copyright (C) 2017 Hans de Goede <hdegoede@redhat.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * Some Intel Cherry Trail based device which ship with Windows 10, have
  11  * this weird INT33FE ACPI device with a CRS table with 4 I2cSerialBusV2
  12  * resources, for 4 different chips attached to various i2c busses:
  13  * 1. The Whiskey Cove pmic, which is also described by the INT34D3 ACPI device
  14  * 2. Maxim MAX17047 Fuel Gauge Controller
  15  * 3. FUSB302 USB Type-C Controller
  16  * 4. PI3USB30532 USB switch
  17  *
  18  * So this driver is a stub / pseudo driver whose only purpose is to
  19  * instantiate i2c-clients for chips 2 - 4, so that standard i2c drivers
  20  * for these chips can bind to the them.
  21  */
  22
  23 #include <linux/acpi.h>
  24 #include <linux/i2c.h>
  25 #include <linux/interrupt.h>
  26 #include <linux/module.h>
  27 #include <linux/regulator/consumer.h>
  28 #include <linux/slab.h>
  29
  30 #define EXPECTED_PTYPE          4
  31
  32 struct cht_int33fe_data {
  33         struct i2c_client *max17047;
  34         struct i2c_client *fusb302;
  35         struct i2c_client *pi3usb30532;
  36 };
  37
  38 /*
  39  * Grrr I severly dislike buggy BIOS-es. At least one BIOS enumerates
  40  * the max17047 both through the INT33FE ACPI device (it is right there
  41  * in the resources table) as well as through a separate MAX17047 device.
  42  *
  43  * These helpers are used to work around this by checking if an i2c-client
  44  * for the max17047 has already been registered.
  45  */
  46 static int cht_int33fe_check_for_max17047(struct device *dev, void *data)
  47 {
  48         struct i2c_client **max17047 = data;
  49         struct acpi_device *adev;
  50         const char *hid;
  51
  52         adev = ACPI_COMPANION(dev);
  53         if (!adev)
  54                 return 0;
  55
  56         hid = acpi_device_hid(adev);
  57
  58         /* The MAX17047 ACPI node doesn't have an UID, so we don't check that */
  59         if (strcmp(hid, "MAX17047"))
  60                 return 0;
  61
  62         *max17047 = to_i2c_client(dev);
  63         return 1;
  64 }
  65
  66 static struct i2c_client *cht_int33fe_find_max17047(void)
  67 {
  68         struct i2c_client *max17047 = NULL;
  69
  70         i2c_for_each_dev(&max17047, cht_int33fe_check_for_max17047);
  71         return max17047;
  72 }
  73
  74 static const char * const max17047_suppliers[] = { "bq24190-charger" };
  75
  76 static const struct property_entry max17047_props[] = {
  77         PROPERTY_ENTRY_STRING_ARRAY("supplied-from", max17047_suppliers),
  78         { }
  79 };
  80
  81 static const struct property_entry fusb302_props[] = {
  82         PROPERTY_ENTRY_STRING("fcs,extcon-name", "cht_wcove_pwrsrc"),
  83         PROPERTY_ENTRY_U32("fcs,max-sink-microvolt", 12000000),
  84         PROPERTY_ENTRY_U32("fcs,max-sink-microamp",   3000000),
  85         PROPERTY_ENTRY_U32("fcs,max-sink-microwatt", 36000000),
  86         { }
  87 };
  88
  89 static int cht_int33fe_probe(struct i2c_client *client)
  90 {
  91         struct device *dev = &client->dev;
  92         struct i2c_board_info board_info;
  93         struct cht_int33fe_data *data;
  94         struct i2c_client *max17047;
  95         struct regulator *regulator;
  96         unsigned long long ptyp;
  97         acpi_status status;
  98         int fusb302_irq;
  99         int ret;
 100
 101         status = acpi_evaluate_integer(ACPI_HANDLE(dev), "PTYP", NULL, &ptyp);
 102         if (ACPI_FAILURE(status)) {
 103                 dev_err(dev, "Error getting PTYPE\n");
 104                 return -ENODEV;
 105         }
 106
 107         /*
 108          * The same ACPI HID is used for different configurations check PTYP
 109          * to ensure that we are dealing with the expected config.
 110          */
 111         if (ptyp != EXPECTED_PTYPE)
 112                 return -ENODEV;
 113
 114         /* Check presence of INT34D3 (hardware-rev 3) expected for ptype == 4 */
 115         if (!acpi_dev_present("INT34D3", "1", 3)) {
 116                 dev_err(dev, "Error PTYPE == %d, but no INT34D3 device\n",
 117                         EXPECTED_PTYPE);
 118                 return -ENODEV;
 119         }
 120
 121         /*
 122          * We expect the WC PMIC to be paired with a TI bq24292i charger-IC.
 123          * We check for the bq24292i vbus regulator here, this has 2 purposes:
 124          * 1) The bq24292i allows charging with up to 12V, setting the fusb302's
 125          *    max-snk voltage to 12V with another charger-IC is not good.
 126          * 2) For the fusb302 driver to get the bq24292i vbus regulator, the
 127          *    regulator-map, which is part of the bq24292i regulator_init_data,
 128          *    must be registered before the fusb302 is instantiated, otherwise
 129          *    it will end up with a dummy-regulator.
 130          * Note "cht_wc_usb_typec_vbus" comes from the regulator_init_data
 131          * which is defined in i2c-cht-wc.c from where the bq24292i i2c-client
 132          * gets instantiated. We use regulator_get_optional here so that we
 133          * don't end up getting a dummy-regulator ourselves.
 134          */
 135         regulator = regulator_get_optional(dev, "cht_wc_usb_typec_vbus");
 136         if (IS_ERR(regulator)) {
 137                 ret = PTR_ERR(regulator);
 138                 return (ret == -ENODEV) ? -EPROBE_DEFER : ret;
 139         }
 140         regulator_put(regulator);
 141
 142         /* The FUSB302 uses the irq at index 1 and is the only irq user */
 143         fusb302_irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(dev), 1);
 144         if (fusb302_irq < 0) {
 145                 if (fusb302_irq != -EPROBE_DEFER)
 146                         dev_err(dev, "Error getting FUSB302 irq\n");
 147                 return fusb302_irq;
 148         }
 149
 150         data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 151         if (!data)
 152                 return -ENOMEM;
 153
 154         /* Work around BIOS bug, see comment on cht_int33fe_find_max17047 */
 155         max17047 = cht_int33fe_find_max17047();
 156         if (max17047) {
 157                 /* Pre-existing i2c-client for the max17047, add device-props */
 158                 ret = device_add_properties(&max17047->dev, max17047_props);
 159                 if (ret)
 160                         return ret;
 161                 /* And re-probe to get the new device-props applied. */
 162                 ret = device_reprobe(&max17047->dev);
 163                 if (ret)
 164                         dev_warn(dev, "Reprobing max17047 error: %d\n", ret);
 165         } else {
 166                 memset(&board_info, 0, sizeof(board_info));
 167                 strlcpy(board_info.type, "max17047", I2C_NAME_SIZE);
 168                 board_info.dev_name = "max17047";
 169                 board_info.properties = max17047_props;
 170                 data->max17047 = i2c_acpi_new_device(dev, 1, &board_info);
 171                 if (!data->max17047)
 172                         return -EPROBE_DEFER; /* Wait for i2c-adapter to load */
 173         }
 174
 175         memset(&board_info, 0, sizeof(board_info));
 176         strlcpy(board_info.type, "typec_fusb302", I2C_NAME_SIZE);
 177         board_info.dev_name = "fusb302";
 178         board_info.properties = fusb302_props;
 179         board_info.irq = fusb302_irq;
 180
 181         data->fusb302 = i2c_acpi_new_device(dev, 2, &board_info);
 182         if (!data->fusb302)
 183                 goto out_unregister_max17047;
 184
 185         memset(&board_info, 0, sizeof(board_info));
 186         board_info.dev_name = "pi3usb30532";
 187         strlcpy(board_info.type, "pi3usb30532", I2C_NAME_SIZE);
 188
 189         data->pi3usb30532 = i2c_acpi_new_device(dev, 3, &board_info);
 190         if (!data->pi3usb30532)
 191                 goto out_unregister_fusb302;
 192
 193         i2c_set_clientdata(client, data);
 194
 195         return 0;
 196
 197 out_unregister_fusb302:
 198         i2c_unregister_device(data->fusb302);
 199
 200 out_unregister_max17047:
 201         if (data->max17047)
 202                 i2c_unregister_device(data->max17047);
 203
 204         return -EPROBE_DEFER; /* Wait for the i2c-adapter to load */
 205 }
 206
 207 static int cht_int33fe_remove(struct i2c_client *i2c)
 208 {
 209         struct cht_int33fe_data *data = i2c_get_clientdata(i2c);
 210
 211         i2c_unregister_device(data->pi3usb30532);
 212         i2c_unregister_device(data->fusb302);
 213         if (data->max17047)
 214                 i2c_unregister_device(data->max17047);
 215
 216         return 0;
 217 }
 218
 219 static const struct i2c_device_id cht_int33fe_i2c_id[] = {
 220         { }
 221 };
 222 MODULE_DEVICE_TABLE(i2c, cht_int33fe_i2c_id);
 223
 224 static const struct acpi_device_id cht_int33fe_acpi_ids[] = {
 225         { "INT33FE", },
 226         { }
 227 };
 228 MODULE_DEVICE_TABLE(acpi, cht_int33fe_acpi_ids);
 229
 230 static struct i2c_driver cht_int33fe_driver = {
 231         .driver = {
 232                 .name = "Intel Cherry Trail ACPI INT33FE driver",
 233                 .acpi_match_table = ACPI_PTR(cht_int33fe_acpi_ids),
 234         },
 235         .probe_new = cht_int33fe_probe,
 236         .remove = cht_int33fe_remove,
 237         .id_table = cht_int33fe_i2c_id,
 238         .disable_i2c_core_irq_mapping = true,
 239 };
 240
 241 module_i2c_driver(cht_int33fe_driver);
 242
 243 MODULE_DESCRIPTION("Intel Cherry Trail ACPI INT33FE pseudo device driver");
 244 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
 245 MODULE_LICENSE("GPL");