xref: /openbmc/linux/drivers/pnp/support.c (revision cfbb9be8)
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 }
180