1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * cardbus.c -- 16-bit PCMCIA core support
4  *
5  * The initial developer of the original code is David A. Hinds
6  * <dahinds@users.sourceforge.net>.  Portions created by David A. Hinds
7  * are Copyright (C) 1999 David A. Hinds.  All Rights Reserved.
8  *
9  * (C) 1999		David A. Hinds
10  */
11 
12 /*
13  * Cardbus handling has been re-written to be more of a PCI bridge thing,
14  * and the PCI code basically does all the resource handling.
15  *
16  *		Linus, Jan 2000
17  */
18 
19 
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/pci.h>
23 
24 #include <pcmcia/ss.h>
25 #include <pcmcia/cistpl.h>
26 
27 #include "cs_internal.h"
28 
29 static void cardbus_config_irq_and_cls(struct pci_bus *bus, int irq)
30 {
31 	struct pci_dev *dev;
32 
33 	list_for_each_entry(dev, &bus->devices, bus_list) {
34 		u8 irq_pin;
35 
36 		/*
37 		 * Since there is only one interrupt available to
38 		 * CardBus devices, all devices downstream of this
39 		 * device must be using this IRQ.
40 		 */
41 		pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq_pin);
42 		if (irq_pin) {
43 			dev->irq = irq;
44 			pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);
45 		}
46 
47 		/*
48 		 * Some controllers transfer very slowly with 0 CLS.
49 		 * Configure it.  This may fail as CLS configuration
50 		 * is mandatory only for MWI.
51 		 */
52 		pci_set_cacheline_size(dev);
53 
54 		if (dev->subordinate)
55 			cardbus_config_irq_and_cls(dev->subordinate, irq);
56 	}
57 }
58 
59 /**
60  * cb_alloc() - add CardBus device
61  * @s:		the pcmcia_socket where the CardBus device is located
62  *
63  * cb_alloc() allocates the kernel data structures for a Cardbus device
64  * and handles the lowest level PCI device setup issues.
65  */
66 int __ref cb_alloc(struct pcmcia_socket *s)
67 {
68 	struct pci_bus *bus = s->cb_dev->subordinate;
69 	struct pci_dev *dev;
70 	unsigned int max, pass;
71 
72 	pci_lock_rescan_remove();
73 
74 	s->functions = pci_scan_slot(bus, PCI_DEVFN(0, 0));
75 
76 	max = bus->busn_res.start;
77 	for (pass = 0; pass < 2; pass++)
78 		for_each_pci_bridge(dev, bus)
79 			max = pci_scan_bridge(bus, dev, max, pass);
80 
81 	/*
82 	 * Size all resources below the CardBus controller.
83 	 */
84 	pci_bus_size_bridges(bus);
85 	pci_bus_assign_resources(bus);
86 	cardbus_config_irq_and_cls(bus, s->pci_irq);
87 
88 	/* socket specific tune function */
89 	if (s->tune_bridge)
90 		s->tune_bridge(s, bus);
91 
92 	pci_bus_add_devices(bus);
93 
94 	pci_unlock_rescan_remove();
95 	return 0;
96 }
97 
98 /**
99  * cb_free() - remove CardBus device
100  * @s:		the pcmcia_socket where the CardBus device was located
101  *
102  * cb_free() handles the lowest level PCI device cleanup.
103  */
104 void cb_free(struct pcmcia_socket *s)
105 {
106 	struct pci_dev *bridge, *dev, *tmp;
107 	struct pci_bus *bus;
108 
109 	bridge = s->cb_dev;
110 	if (!bridge)
111 		return;
112 
113 	bus = bridge->subordinate;
114 	if (!bus)
115 		return;
116 
117 	pci_lock_rescan_remove();
118 
119 	list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list)
120 		pci_stop_and_remove_bus_device(dev);
121 
122 	pci_unlock_rescan_remove();
123 }
124