xref: /openbmc/linux/drivers/pnp/support.c (revision f052febd)
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 EXPORT_SYMBOL(pnp_is_active);
34 
35 /*
36  * Functionally similar to acpi_ex_eisa_id_to_string(), but that's
37  * buried in the ACPI CA, and we can't depend on it being present.
38  */
39 void pnp_eisa_id_to_string(u32 id, char *str)
40 {
41 	id = be32_to_cpu(id);
42 
43 	/*
44 	 * According to the specs, the first three characters are five-bit
45 	 * compressed ASCII, and the left-over high order bit should be zero.
46 	 * However, the Linux ISAPNP code historically used six bits for the
47 	 * first character, and there seem to be IDs that depend on that,
48 	 * e.g., "nEC8241" in the Linux 8250_pnp serial driver and the
49 	 * FreeBSD sys/pc98/cbus/sio_cbus.c driver.
50 	 */
51 	str[0] = 'A' + ((id >> 26) & 0x3f) - 1;
52 	str[1] = 'A' + ((id >> 21) & 0x1f) - 1;
53 	str[2] = 'A' + ((id >> 16) & 0x1f) - 1;
54 	str[3] = hex_asc_hi(id >> 8);
55 	str[4] = hex_asc_lo(id >> 8);
56 	str[5] = hex_asc_hi(id);
57 	str[6] = hex_asc_lo(id);
58 	str[7] = '\0';
59 }
60 
61 char *pnp_resource_type_name(struct resource *res)
62 {
63 	switch (pnp_resource_type(res)) {
64 	case IORESOURCE_IO:
65 		return "io";
66 	case IORESOURCE_MEM:
67 		return "mem";
68 	case IORESOURCE_IRQ:
69 		return "irq";
70 	case IORESOURCE_DMA:
71 		return "dma";
72 	case IORESOURCE_BUS:
73 		return "bus";
74 	}
75 	return "unknown";
76 }
77 
78 void dbg_pnp_show_resources(struct pnp_dev *dev, char *desc)
79 {
80 	struct pnp_resource *pnp_res;
81 
82 	if (list_empty(&dev->resources))
83 		pnp_dbg(&dev->dev, "%s: no current resources\n", desc);
84 	else {
85 		pnp_dbg(&dev->dev, "%s: current resources:\n", desc);
86 		list_for_each_entry(pnp_res, &dev->resources, list)
87 			pnp_dbg(&dev->dev, "%pr\n", &pnp_res->res);
88 	}
89 }
90 
91 char *pnp_option_priority_name(struct pnp_option *option)
92 {
93 	switch (pnp_option_priority(option)) {
94 	case PNP_RES_PRIORITY_PREFERRED:
95 		return "preferred";
96 	case PNP_RES_PRIORITY_ACCEPTABLE:
97 		return "acceptable";
98 	case PNP_RES_PRIORITY_FUNCTIONAL:
99 		return "functional";
100 	}
101 	return "invalid";
102 }
103 
104 void dbg_pnp_show_option(struct pnp_dev *dev, struct pnp_option *option)
105 {
106 	char buf[128];
107 	int len = 0, i;
108 	struct pnp_port *port;
109 	struct pnp_mem *mem;
110 	struct pnp_irq *irq;
111 	struct pnp_dma *dma;
112 
113 	if (pnp_option_is_dependent(option))
114 		len += scnprintf(buf + len, sizeof(buf) - len,
115 				 "  dependent set %d (%s) ",
116 				 pnp_option_set(option),
117 				 pnp_option_priority_name(option));
118 	else
119 		len += scnprintf(buf + len, sizeof(buf) - len,
120 				 "  independent ");
121 
122 	switch (option->type) {
123 	case IORESOURCE_IO:
124 		port = &option->u.port;
125 		len += scnprintf(buf + len, sizeof(buf) - len, "io  min %#llx "
126 				 "max %#llx align %lld size %lld flags %#x",
127 				 (unsigned long long) port->min,
128 				 (unsigned long long) port->max,
129 				 (unsigned long long) port->align,
130 				 (unsigned long long) port->size, port->flags);
131 		break;
132 	case IORESOURCE_MEM:
133 		mem = &option->u.mem;
134 		len += scnprintf(buf + len, sizeof(buf) - len, "mem min %#llx "
135 				 "max %#llx align %lld size %lld flags %#x",
136 				 (unsigned long long) mem->min,
137 				 (unsigned long long) mem->max,
138 				 (unsigned long long) mem->align,
139 				 (unsigned long long) mem->size, mem->flags);
140 		break;
141 	case IORESOURCE_IRQ:
142 		irq = &option->u.irq;
143 		len += scnprintf(buf + len, sizeof(buf) - len, "irq");
144 		if (bitmap_empty(irq->map.bits, PNP_IRQ_NR))
145 			len += scnprintf(buf + len, sizeof(buf) - len,
146 					 " <none>");
147 		else {
148 			for (i = 0; i < PNP_IRQ_NR; i++)
149 				if (test_bit(i, irq->map.bits))
150 					len += scnprintf(buf + len,
151 							 sizeof(buf) - len,
152 							 " %d", i);
153 		}
154 		len += scnprintf(buf + len, sizeof(buf) - len, " flags %#x",
155 				 irq->flags);
156 		if (irq->flags & IORESOURCE_IRQ_OPTIONAL)
157 			len += scnprintf(buf + len, sizeof(buf) - len,
158 					 " (optional)");
159 		break;
160 	case IORESOURCE_DMA:
161 		dma = &option->u.dma;
162 		len += scnprintf(buf + len, sizeof(buf) - len, "dma");
163 		if (!dma->map)
164 			len += scnprintf(buf + len, sizeof(buf) - len,
165 					 " <none>");
166 		else {
167 			for (i = 0; i < 8; i++)
168 				if (dma->map & (1 << i))
169 					len += scnprintf(buf + len,
170 							 sizeof(buf) - len,
171 							 " %d", i);
172 		}
173 		len += scnprintf(buf + len, sizeof(buf) - len, " (bitmask %#x) "
174 				 "flags %#x", dma->map, dma->flags);
175 		break;
176 	}
177 	pnp_dbg(&dev->dev, "%s\n", buf);
178 }
179