cmd/w1.c

   1 /* SPDX-License-Identifier: GPL-2.0+
   2  *
   3  * (C) Copyright 2018
   4  * Microchip Technology, Inc.
   5  * Eugen Hristev <eugen.hristev@microchip.com>
   6  */
   7 #include <common.h>
   8 #include <command.h>
   9 #include <dm.h>
  10 #include <w1.h>
  11 #include <w1-eeprom.h>
  12 #include <dm/device-internal.h>
  13
  14 static int w1_bus(void)
  15 {
  16         struct udevice *bus, *dev;
  17         int ret;
  18
  19         ret = w1_get_bus(0, &bus);
  20         if (ret) {
  21                 printf("one wire interface not found\n");
  22                 return CMD_RET_FAILURE;
  23         }
  24         printf("Bus %d:\t%s", dev_seq(bus), bus->name);
  25         if (device_active(bus))
  26                 printf("  (active)");
  27         printf("\n");
  28
  29         for (device_find_first_child(bus, &dev);
  30              dev;
  31              device_find_next_child(&dev)) {
  32                 ret = device_probe(dev);
  33
  34                 printf("\t%s (%d) uclass %s : ", dev->name, dev_seq(dev),
  35                        dev->uclass->uc_drv->name);
  36
  37                 if (ret)
  38                         printf("device error\n");
  39                 else
  40                         printf("family 0x%x\n", w1_get_device_family(dev));
  41         }
  42         return CMD_RET_SUCCESS;
  43 }
  44
  45 static int w1_read(int argc, char *const argv[])
  46 {
  47         int bus_n = 0, dev_n = 0, offset = 0, len = 512;
  48         int i;
  49         struct udevice *bus, *dev;
  50         int ret;
  51         u8 buf[512];
  52
  53         if (argc > 2)
  54                 bus_n = dectoul(argv[2], NULL);
  55
  56         if (argc > 3)
  57                 dev_n = dectoul(argv[3], NULL);
  58
  59         if (argc > 4)
  60                 offset = dectoul(argv[4], NULL);
  61
  62         if (argc > 5)
  63                 len = dectoul(argv[5], NULL);
  64
  65         if (len > 512) {
  66                 printf("len needs to be <= 512\n");
  67                 return CMD_RET_FAILURE;
  68         }
  69
  70         ret = w1_get_bus(bus_n, &bus);
  71         if (ret) {
  72                 printf("one wire interface not found\n");
  73                 return CMD_RET_FAILURE;
  74         }
  75
  76         for (device_find_first_child(bus, &dev), i = 0;
  77            dev && i <= dev_n;
  78            device_find_next_child(&dev), i++) {
  79                 ret = device_probe(dev);
  80                 if (!ret && i == dev_n)
  81                         break;
  82         }
  83
  84         if (i != dev_n || ret || !dev) {
  85                 printf("invalid dev\n");
  86                 return CMD_RET_FAILURE;
  87         }
  88
  89         if (strcmp(dev->uclass->uc_drv->name, "w1_eeprom")) {
  90                 printf("the device present on the interface is of unknown device class\n");
  91                 return CMD_RET_FAILURE;
  92         }
  93
  94         ret = w1_eeprom_read_buf(dev, offset, (u8 *)buf, len);
  95         if (ret) {
  96                 printf("error reading device %s\n", dev->name);
  97                 return CMD_RET_FAILURE;
  98         }
  99
 100         for (i = 0; i < len; i++)
 101                 printf("%x", buf[i]);
 102         printf("\n");
 103
 104         return CMD_RET_SUCCESS;
 105 }
 106
 107 int do_w1(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
 108 {
 109         if (argc < 2)
 110                 return CMD_RET_USAGE;
 111
 112         if (!strcmp(argv[1], "bus"))
 113                 return w1_bus();
 114
 115         if (!strcmp(argv[1], "read"))
 116                 return w1_read(argc, argv);
 117
 118         return CMD_RET_SUCCESS;
 119 }
 120
 121 U_BOOT_CMD(w1, 6, 0, do_w1,
 122            "onewire interface utility commands",
 123            "bus - show onewire bus info (all)\n"
 124            "w1 read [<bus> [<dev> [offset [length]]]]"
 125            "    - read from onewire device 'dev' on onewire bus 'bus'"
 126            " starting from offset 'offset' and length 'length'\n"
 127            "      defaults: bus 0, dev 0, offset 0, length 512 bytes.");