drivers/w1-eeprom/w1-eeprom-uclass.c

   1 // SPDX-License-Identifier:     GPL-2.0+
   2 /*
   3  *
   4  * Copyright (c) 2015 Free Electrons
   5  * Copyright (c) 2015 NextThing Co.
   6  * Copyright (c) 2018 Microchip Technology, Inc.
   7  *
   8  * Maxime Ripard <maxime.ripard@free-electrons.com>
   9  * Eugen Hristev <eugen.hristev@microchip.com>
  10  *
  11  */
  12
  13 #include <common.h>
  14 #include <dm.h>
  15 #include <w1.h>
  16 #include <w1-eeprom.h>
  17
  18 #include <dm/device-internal.h>
  19
  20 int w1_eeprom_read_buf(struct udevice *dev, unsigned int offset,
  21                        u8 *buf, unsigned int count)
  22 {
  23         const struct w1_eeprom_ops *ops = device_get_ops(dev);
  24         u64 id = 0;
  25         int ret;
  26
  27         if (!ops->read_buf)
  28                 return -ENOSYS;
  29
  30         ret = w1_eeprom_get_id(dev, &id);
  31         if (ret)
  32                 return ret;
  33         if (!id)
  34                 return -ENODEV;
  35
  36         return ops->read_buf(dev, offset, buf, count);
  37 }
  38
  39 int w1_eeprom_register_new_device(u64 id)
  40 {
  41         u8 family = id & 0xff;
  42         int ret;
  43         struct udevice *dev;
  44
  45         for (ret = uclass_first_device(UCLASS_W1_EEPROM, &dev);
  46              !ret && dev;
  47              uclass_next_device(&dev)) {
  48                 if (ret || !dev) {
  49                         debug("cannot find w1 eeprom dev\n");
  50                         return ret;
  51                 }
  52                 if (dev_get_driver_data(dev) == family) {
  53                         struct w1_device *w1;
  54
  55                         w1 = dev_get_parent_platdata(dev);
  56                         if (w1->id) /* device already in use */
  57                                 continue;
  58                         w1->id = id;
  59                         debug("%s: Match found: %s:%s %llx\n", __func__,
  60                               dev->name, dev->driver->name, id);
  61                         return 0;
  62                 }
  63         }
  64
  65         debug("%s: No matches found: error %d\n", __func__, ret);
  66
  67         return ret;
  68 }
  69
  70 int w1_eeprom_get_id(struct udevice *dev, u64 *id)
  71 {
  72         struct w1_device *w1 = dev_get_parent_platdata(dev);
  73
  74         if (!w1)
  75                 return -ENODEV;
  76         *id = w1->id;
  77
  78         return 0;
  79 }
  80
  81 UCLASS_DRIVER(w1_eeprom) = {
  82         .name           = "w1_eeprom",
  83         .id             = UCLASS_W1_EEPROM,
  84         .flags          = DM_UC_FLAG_SEQ_ALIAS,
  85 #if CONFIG_IS_ENABLED(OF_CONTROL)
  86         .post_bind      = dm_scan_fdt_dev,
  87 #endif
  88 };
  89
  90 int w1_eeprom_dm_init(void)
  91 {
  92         struct udevice *dev;
  93         struct uclass *uc;
  94         int ret;
  95
  96         ret = uclass_get(UCLASS_W1_EEPROM, &uc);
  97         if (ret) {
  98                 debug("W1_EEPROM uclass not available\n");
  99                 return ret;
 100         }
 101
 102         uclass_foreach_dev(dev, uc) {
 103                 ret = device_probe(dev);
 104                 if (ret == -ENODEV) {   /* No such device. */
 105                         debug("W1_EEPROM not available.\n");
 106                         continue;
 107                 }
 108
 109                 if (ret) {              /* Other error. */
 110                         printf("W1_EEPROM probe failed, error %d\n", ret);
 111                         continue;
 112                 }
 113         }
 114
 115         return 0;
 116 }