board/sunxi/chip.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * (C) Copyright 2021
   4  * Köry Maincent, Bootlin, <[email protected]>
   5  * Based on initial code from Maxime Ripard
   6  */
   7
   8 #include <malloc.h>
   9 #include <dm.h>
  10 #include <w1.h>
  11 #include <w1-eeprom.h>
  12 #include <dm/device-internal.h>
  13
  14 #include <sunxi_gpio.h>
  15
  16 #include <extension_board.h>
  17
  18 #define for_each_w1_device(b, d) \
  19         for (device_find_first_child(b, d); *d; device_find_next_child(d))
  20
  21 #define dip_convert(field)                                              \
  22         (                                                               \
  23                 (sizeof(field) == 1) ? field :                          \
  24                 (sizeof(field) == 2) ? be16_to_cpu(field) :             \
  25                 (sizeof(field) == 4) ? be32_to_cpu(field) :             \
  26                 -1                                                      \
  27         )
  28
  29 #define DIP_MAGIC       0x50494843      /* CHIP */
  30
  31 struct dip_w1_header {
  32         u32     magic;                  /* CHIP */
  33         u8      version;                /* spec version */
  34         u32     vendor_id;
  35         u16     product_id;
  36         u8      product_version;
  37         char    vendor_name[32];
  38         char    product_name[32];
  39         u8      rsvd[36];               /* rsvd for future spec versions */
  40         u8      data[16];               /* user data, per-dip specific */
  41 } __packed;
  42
  43 int extension_board_scan(struct list_head *extension_list)
  44 {
  45         struct extension *dip;
  46         struct dip_w1_header w1_header;
  47         struct udevice *bus, *dev;
  48         u32 vid;
  49         u16 pid;
  50         int ret;
  51
  52         int num_dip = 0;
  53
  54         sunxi_gpio_set_pull(SUNXI_GPD(2), SUNXI_GPIO_PULL_UP);
  55
  56         ret = w1_get_bus(0, &bus);
  57         if (ret) {
  58                 printf("one wire interface not found\n");
  59                 return 0;
  60         }
  61
  62         for_each_w1_device(bus, &dev) {
  63                 if (w1_get_device_family(dev) != W1_FAMILY_DS2431)
  64                         continue;
  65
  66                 ret = device_probe(dev);
  67                 if (ret) {
  68                         printf("Couldn't probe device %s: error %d",
  69                                dev->name, ret);
  70                         continue;
  71                 }
  72
  73                 w1_eeprom_read_buf(dev, 0, (u8 *)&w1_header, sizeof(w1_header));
  74
  75                 if (w1_header.magic != DIP_MAGIC)
  76                         continue;
  77
  78                 vid = dip_convert(w1_header.vendor_id);
  79                 pid = dip_convert(w1_header.product_id);
  80
  81                 printf("DIP: %s (0x%x) from %s (0x%x)\n",
  82                        w1_header.product_name, pid,
  83                        w1_header.vendor_name, vid);
  84
  85                 dip = calloc(1, sizeof(struct extension));
  86                 if (!dip) {
  87                         printf("Error in memory allocation\n");
  88                         return num_dip;
  89                 }
  90
  91                 snprintf(dip->overlay, sizeof(dip->overlay), "dip-%x-%x.dtbo",
  92                          vid, pid);
  93                 strncpy(dip->name, w1_header.product_name, 32);
  94                 strncpy(dip->owner, w1_header.vendor_name, 32);
  95                 list_add_tail(&dip->list, extension_list);
  96                 num_dip++;
  97         }
  98         return num_dip;
  99 }