xref: /linux/drivers/pci/hotplug/pciehp_core.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * PCI Express Hot Plug Controller Driver
3  *
4  * Copyright (C) 1995,2001 Compaq Computer Corporation
5  * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
6  * Copyright (C) 2001 IBM Corp.
7  * Copyright (C) 2003-2004 Intel Corporation
8  *
9  * All rights reserved.
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or (at
14  * your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful, but
17  * WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
19  * NON INFRINGEMENT.  See the GNU General Public License for more
20  * details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25  *
26  * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
27  *
28  */
29 
30 #include <linux/module.h>
31 #include <linux/moduleparam.h>
32 #include <linux/kernel.h>
33 #include <linux/slab.h>
34 #include <linux/types.h>
35 #include <linux/pci.h>
36 #include "pciehp.h"
37 #include <linux/interrupt.h>
38 #include <linux/time.h>
39 
40 /* Global variables */
41 bool pciehp_debug;
42 bool pciehp_poll_mode;
43 int pciehp_poll_time;
44 static bool pciehp_force;
45 
46 #define DRIVER_VERSION	"0.4"
47 #define DRIVER_AUTHOR	"Dan Zink <dan.zink@compaq.com>, Greg Kroah-Hartman <greg@kroah.com>, Dely Sy <dely.l.sy@intel.com>"
48 #define DRIVER_DESC	"PCI Express Hot Plug Controller Driver"
49 
50 MODULE_AUTHOR(DRIVER_AUTHOR);
51 MODULE_DESCRIPTION(DRIVER_DESC);
52 MODULE_LICENSE("GPL");
53 
54 module_param(pciehp_debug, bool, 0644);
55 module_param(pciehp_poll_mode, bool, 0644);
56 module_param(pciehp_poll_time, int, 0644);
57 module_param(pciehp_force, bool, 0644);
58 MODULE_PARM_DESC(pciehp_debug, "Debugging mode enabled or not");
59 MODULE_PARM_DESC(pciehp_poll_mode, "Using polling mechanism for hot-plug events or not");
60 MODULE_PARM_DESC(pciehp_poll_time, "Polling mechanism frequency, in seconds");
61 MODULE_PARM_DESC(pciehp_force, "Force pciehp, even if OSHP is missing");
62 
63 #define PCIE_MODULE_NAME "pciehp"
64 
65 static int set_attention_status (struct hotplug_slot *slot, u8 value);
66 static int enable_slot		(struct hotplug_slot *slot);
67 static int disable_slot		(struct hotplug_slot *slot);
68 static int get_power_status	(struct hotplug_slot *slot, u8 *value);
69 static int get_attention_status	(struct hotplug_slot *slot, u8 *value);
70 static int get_latch_status	(struct hotplug_slot *slot, u8 *value);
71 static int get_adapter_status	(struct hotplug_slot *slot, u8 *value);
72 static int reset_slot		(struct hotplug_slot *slot, int probe);
73 
74 /**
75  * release_slot - free up the memory used by a slot
76  * @hotplug_slot: slot to free
77  */
78 static void release_slot(struct hotplug_slot *hotplug_slot)
79 {
80 	kfree(hotplug_slot->ops);
81 	kfree(hotplug_slot->info);
82 	kfree(hotplug_slot);
83 }
84 
85 static int init_slot(struct controller *ctrl)
86 {
87 	struct slot *slot = ctrl->slot;
88 	struct hotplug_slot *hotplug = NULL;
89 	struct hotplug_slot_info *info = NULL;
90 	struct hotplug_slot_ops *ops = NULL;
91 	char name[SLOT_NAME_SIZE];
92 	int retval = -ENOMEM;
93 
94 	hotplug = kzalloc(sizeof(*hotplug), GFP_KERNEL);
95 	if (!hotplug)
96 		goto out;
97 
98 	info = kzalloc(sizeof(*info), GFP_KERNEL);
99 	if (!info)
100 		goto out;
101 
102 	/* Setup hotplug slot ops */
103 	ops = kzalloc(sizeof(*ops), GFP_KERNEL);
104 	if (!ops)
105 		goto out;
106 
107 	ops->enable_slot = enable_slot;
108 	ops->disable_slot = disable_slot;
109 	ops->get_power_status = get_power_status;
110 	ops->get_adapter_status = get_adapter_status;
111 	ops->reset_slot = reset_slot;
112 	if (MRL_SENS(ctrl))
113 		ops->get_latch_status = get_latch_status;
114 	if (ATTN_LED(ctrl)) {
115 		ops->get_attention_status = get_attention_status;
116 		ops->set_attention_status = set_attention_status;
117 	}
118 
119 	/* register this slot with the hotplug pci core */
120 	hotplug->info = info;
121 	hotplug->private = slot;
122 	hotplug->release = &release_slot;
123 	hotplug->ops = ops;
124 	slot->hotplug_slot = hotplug;
125 	snprintf(name, SLOT_NAME_SIZE, "%u", PSN(ctrl));
126 
127 	retval = pci_hp_register(hotplug,
128 				 ctrl->pcie->port->subordinate, 0, name);
129 	if (retval)
130 		ctrl_err(ctrl, "pci_hp_register failed: error %d\n", retval);
131 out:
132 	if (retval) {
133 		kfree(ops);
134 		kfree(info);
135 		kfree(hotplug);
136 	}
137 	return retval;
138 }
139 
140 static void cleanup_slot(struct controller *ctrl)
141 {
142 	pci_hp_deregister(ctrl->slot->hotplug_slot);
143 }
144 
145 /*
146  * set_attention_status - Turns the Amber LED for a slot on, off or blink
147  */
148 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
149 {
150 	struct slot *slot = hotplug_slot->private;
151 
152 	pciehp_set_attention_status(slot, status);
153 	return 0;
154 }
155 
156 
157 static int enable_slot(struct hotplug_slot *hotplug_slot)
158 {
159 	struct slot *slot = hotplug_slot->private;
160 
161 	return pciehp_sysfs_enable_slot(slot);
162 }
163 
164 
165 static int disable_slot(struct hotplug_slot *hotplug_slot)
166 {
167 	struct slot *slot = hotplug_slot->private;
168 
169 	return pciehp_sysfs_disable_slot(slot);
170 }
171 
172 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
173 {
174 	struct slot *slot = hotplug_slot->private;
175 
176 	pciehp_get_power_status(slot, value);
177 	return 0;
178 }
179 
180 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
181 {
182 	struct slot *slot = hotplug_slot->private;
183 
184 	pciehp_get_attention_status(slot, value);
185 	return 0;
186 }
187 
188 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
189 {
190 	struct slot *slot = hotplug_slot->private;
191 
192 	pciehp_get_latch_status(slot, value);
193 	return 0;
194 }
195 
196 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
197 {
198 	struct slot *slot = hotplug_slot->private;
199 
200 	pciehp_get_adapter_status(slot, value);
201 	return 0;
202 }
203 
204 static int reset_slot(struct hotplug_slot *hotplug_slot, int probe)
205 {
206 	struct slot *slot = hotplug_slot->private;
207 
208 	return pciehp_reset_slot(slot, probe);
209 }
210 
211 static int pciehp_probe(struct pcie_device *dev)
212 {
213 	int rc;
214 	struct controller *ctrl;
215 	struct slot *slot;
216 	u8 occupied, poweron;
217 
218 	/* If this is not a "hotplug" service, we have no business here. */
219 	if (dev->service != PCIE_PORT_SERVICE_HP)
220 		return -ENODEV;
221 
222 	if (!dev->port->subordinate) {
223 		/* Can happen if we run out of bus numbers during probe */
224 		dev_err(&dev->device,
225 			"Hotplug bridge without secondary bus, ignoring\n");
226 		return -ENODEV;
227 	}
228 
229 	ctrl = pcie_init(dev);
230 	if (!ctrl) {
231 		dev_err(&dev->device, "Controller initialization failed\n");
232 		return -ENODEV;
233 	}
234 	set_service_data(dev, ctrl);
235 
236 	/* Setup the slot information structures */
237 	rc = init_slot(ctrl);
238 	if (rc) {
239 		if (rc == -EBUSY)
240 			ctrl_warn(ctrl, "Slot already registered by another hotplug driver\n");
241 		else
242 			ctrl_err(ctrl, "Slot initialization failed (%d)\n", rc);
243 		goto err_out_release_ctlr;
244 	}
245 
246 	/* Enable events after we have setup the data structures */
247 	rc = pcie_init_notification(ctrl);
248 	if (rc) {
249 		ctrl_err(ctrl, "Notification initialization failed (%d)\n", rc);
250 		goto err_out_free_ctrl_slot;
251 	}
252 
253 	/* Check if slot is occupied */
254 	slot = ctrl->slot;
255 	pciehp_get_adapter_status(slot, &occupied);
256 	pciehp_get_power_status(slot, &poweron);
257 	if (occupied && pciehp_force) {
258 		mutex_lock(&slot->hotplug_lock);
259 		pciehp_enable_slot(slot);
260 		mutex_unlock(&slot->hotplug_lock);
261 	}
262 	/* If empty slot's power status is on, turn power off */
263 	if (!occupied && poweron && POWER_CTRL(ctrl))
264 		pciehp_power_off_slot(slot);
265 
266 	return 0;
267 
268 err_out_free_ctrl_slot:
269 	cleanup_slot(ctrl);
270 err_out_release_ctlr:
271 	pciehp_release_ctrl(ctrl);
272 	return -ENODEV;
273 }
274 
275 static void pciehp_remove(struct pcie_device *dev)
276 {
277 	struct controller *ctrl = get_service_data(dev);
278 
279 	cleanup_slot(ctrl);
280 	pciehp_release_ctrl(ctrl);
281 }
282 
283 #ifdef CONFIG_PM
284 static int pciehp_suspend(struct pcie_device *dev)
285 {
286 	return 0;
287 }
288 
289 static int pciehp_resume(struct pcie_device *dev)
290 {
291 	struct controller *ctrl;
292 	struct slot *slot;
293 	u8 status;
294 
295 	ctrl = get_service_data(dev);
296 
297 	/* reinitialize the chipset's event detection logic */
298 	pcie_enable_notification(ctrl);
299 
300 	slot = ctrl->slot;
301 
302 	/* Check if slot is occupied */
303 	pciehp_get_adapter_status(slot, &status);
304 	mutex_lock(&slot->hotplug_lock);
305 	if (status)
306 		pciehp_enable_slot(slot);
307 	else
308 		pciehp_disable_slot(slot);
309 	mutex_unlock(&slot->hotplug_lock);
310 	return 0;
311 }
312 #endif /* PM */
313 
314 static struct pcie_port_service_driver hpdriver_portdrv = {
315 	.name		= PCIE_MODULE_NAME,
316 	.port_type	= PCIE_ANY_PORT,
317 	.service	= PCIE_PORT_SERVICE_HP,
318 
319 	.probe		= pciehp_probe,
320 	.remove		= pciehp_remove,
321 
322 #ifdef	CONFIG_PM
323 	.suspend	= pciehp_suspend,
324 	.resume		= pciehp_resume,
325 #endif	/* PM */
326 };
327 
328 static int __init pcied_init(void)
329 {
330 	int retval = 0;
331 
332 	retval = pcie_port_service_register(&hpdriver_portdrv);
333 	dbg("pcie_port_service_register = %d\n", retval);
334 	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
335 	if (retval)
336 		dbg("Failure to register service\n");
337 
338 	return retval;
339 }
340 
341 static void __exit pcied_cleanup(void)
342 {
343 	dbg("unload_pciehpd()\n");
344 	pcie_port_service_unregister(&hpdriver_portdrv);
345 	info(DRIVER_DESC " version: " DRIVER_VERSION " unloaded\n");
346 }
347 
348 module_init(pcied_init);
349 module_exit(pcied_cleanup);
350