drivers/pnp/support.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * support.c - standard functions for the use of pnp protocol drivers
   4  *
   5  * Copyright 2003 Adam Belay <ambx1@neo.rr.com>
   6  * Copyright (C) 2008 Hewlett-Packard Development Company, L.P.
   7  *      Bjorn Helgaas <bjorn.helgaas@hp.com>
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/ctype.h>
  12 #include <linux/pnp.h>
  13 #include "base.h"
  14
  15 /**
  16  * pnp_is_active - Determines if a device is active based on its current
  17  *      resources
  18  * @dev: pointer to the desired PnP device
  19  */
  20 int pnp_is_active(struct pnp_dev *dev)
  21 {
  22         /*
  23          * I don't think this is very reliable because pnp_disable_dev()
  24          * only clears out auto-assigned resources.
  25          */
  26         if (!pnp_port_start(dev, 0) && pnp_port_len(dev, 0) <= 1 &&
  27             !pnp_mem_start(dev, 0) && pnp_mem_len(dev, 0) <= 1 &&
  28             pnp_irq(dev, 0) == -1 && pnp_dma(dev, 0) == -1)
  29                 return 0;
  30         else
  31                 return 1;
  32 }
  33
  34 EXPORT_SYMBOL(pnp_is_active);
  35
  36 /*
  37  * Functionally similar to acpi_ex_eisa_id_to_string(), but that's
  38  * buried in the ACPI CA, and we can't depend on it being present.
  39  */
  40 void pnp_eisa_id_to_string(u32 id, char *str)
  41 {
  42         id = be32_to_cpu(id);
  43
  44         /*
  45          * According to the specs, the first three characters are five-bit
  46          * compressed ASCII, and the left-over high order bit should be zero.
  47          * However, the Linux ISAPNP code historically used six bits for the
  48          * first character, and there seem to be IDs that depend on that,
  49          * e.g., "nEC8241" in the Linux 8250_pnp serial driver and the
  50          * FreeBSD sys/pc98/cbus/sio_cbus.c driver.
  51          */
  52         str[0] = 'A' + ((id >> 26) & 0x3f) - 1;
  53         str[1] = 'A' + ((id >> 21) & 0x1f) - 1;
  54         str[2] = 'A' + ((id >> 16) & 0x1f) - 1;
  55         str[3] = hex_asc_hi(id >> 8);
  56         str[4] = hex_asc_lo(id >> 8);
  57         str[5] = hex_asc_hi(id);
  58         str[6] = hex_asc_lo(id);
  59         str[7] = '\0';
  60 }
  61
  62 char *pnp_resource_type_name(struct resource *res)
  63 {
  64         switch (pnp_resource_type(res)) {
  65         case IORESOURCE_IO:
  66                 return "io";
  67         case IORESOURCE_MEM:
  68                 return "mem";
  69         case IORESOURCE_IRQ:
  70                 return "irq";
  71         case IORESOURCE_DMA:
  72                 return "dma";
  73         case IORESOURCE_BUS:
  74                 return "bus";
  75         }
  76         return "unknown";
  77 }
  78
  79 void dbg_pnp_show_resources(struct pnp_dev *dev, char *desc)
  80 {
  81         struct pnp_resource *pnp_res;
  82
  83         if (list_empty(&dev->resources))
  84                 pnp_dbg(&dev->dev, "%s: no current resources\n", desc);
  85         else {
  86                 pnp_dbg(&dev->dev, "%s: current resources:\n", desc);
  87                 list_for_each_entry(pnp_res, &dev->resources, list)
  88                         pnp_dbg(&dev->dev, "%pr\n", &pnp_res->res);
  89         }
  90 }
  91
  92 char *pnp_option_priority_name(struct pnp_option *option)
  93 {
  94         switch (pnp_option_priority(option)) {
  95         case PNP_RES_PRIORITY_PREFERRED:
  96                 return "preferred";
  97         case PNP_RES_PRIORITY_ACCEPTABLE:
  98                 return "acceptable";
  99         case PNP_RES_PRIORITY_FUNCTIONAL:
 100                 return "functional";
 101         }
 102         return "invalid";
 103 }
 104
 105 void dbg_pnp_show_option(struct pnp_dev *dev, struct pnp_option *option)
 106 {
 107         char buf[128];
 108         int len = 0, i;
 109         struct pnp_port *port;
 110         struct pnp_mem *mem;
 111         struct pnp_irq *irq;
 112         struct pnp_dma *dma;
 113
 114         if (pnp_option_is_dependent(option))
 115                 len += scnprintf(buf + len, sizeof(buf) - len,
 116                                  "  dependent set %d (%s) ",
 117                                  pnp_option_set(option),
 118                                  pnp_option_priority_name(option));
 119         else
 120                 len += scnprintf(buf + len, sizeof(buf) - len,
 121                                  "  independent ");
 122
 123         switch (option->type) {
 124         case IORESOURCE_IO:
 125                 port = &option->u.port;
 126                 len += scnprintf(buf + len, sizeof(buf) - len, "io  min %#llx "
 127                                  "max %#llx align %lld size %lld flags %#x",
 128                                  (unsigned long long) port->min,
 129                                  (unsigned long long) port->max,
 130                                  (unsigned long long) port->align,
 131                                  (unsigned long long) port->size, port->flags);
 132                 break;
 133         case IORESOURCE_MEM:
 134                 mem = &option->u.mem;
 135                 len += scnprintf(buf + len, sizeof(buf) - len, "mem min %#llx "
 136                                  "max %#llx align %lld size %lld flags %#x",
 137                                  (unsigned long long) mem->min,
 138                                  (unsigned long long) mem->max,
 139                                  (unsigned long long) mem->align,
 140                                  (unsigned long long) mem->size, mem->flags);
 141                 break;
 142         case IORESOURCE_IRQ:
 143                 irq = &option->u.irq;
 144                 len += scnprintf(buf + len, sizeof(buf) - len, "irq");
 145                 if (bitmap_empty(irq->map.bits, PNP_IRQ_NR))
 146                         len += scnprintf(buf + len, sizeof(buf) - len,
 147                                          " <none>");
 148                 else {
 149                         for (i = 0; i < PNP_IRQ_NR; i++)
 150                                 if (test_bit(i, irq->map.bits))
 151                                         len += scnprintf(buf + len,
 152                                                          sizeof(buf) - len,
 153                                                          " %d", i);
 154                 }
 155                 len += scnprintf(buf + len, sizeof(buf) - len, " flags %#x",
 156                                  irq->flags);
 157                 if (irq->flags & IORESOURCE_IRQ_OPTIONAL)
 158                         len += scnprintf(buf + len, sizeof(buf) - len,
 159                                          " (optional)");
 160                 break;
 161         case IORESOURCE_DMA:
 162                 dma = &option->u.dma;
 163                 len += scnprintf(buf + len, sizeof(buf) - len, "dma");
 164                 if (!dma->map)
 165                         len += scnprintf(buf + len, sizeof(buf) - len,
 166                                          " <none>");
 167                 else {
 168                         for (i = 0; i < 8; i++)
 169                                 if (dma->map & (1 << i))
 170                                         len += scnprintf(buf + len,
 171                                                          sizeof(buf) - len,
 172                                                          " %d", i);
 173                 }
 174                 len += scnprintf(buf + len, sizeof(buf) - len, " (bitmask %#x) "
 175                                  "flags %#x", dma->map, dma->flags);
 176                 break;
 177         }
 178         pnp_dbg(&dev->dev, "%s\n", buf);
 179 }