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  * Authors:
29  *   Dan Zink <dan.zink@compaq.com>
30  *   Greg Kroah-Hartman <greg@kroah.com>
31  *   Dely Sy <dely.l.sy@intel.com>"
32  */
33 
34 #include <linux/moduleparam.h>
35 #include <linux/kernel.h>
36 #include <linux/slab.h>
37 #include <linux/types.h>
38 #include <linux/pci.h>
39 #include "pciehp.h"
40 #include <linux/interrupt.h>
41 #include <linux/time.h>
42 
43 /* Global variables */
44 bool pciehp_debug;
45 bool pciehp_poll_mode;
46 int pciehp_poll_time;
47 static bool pciehp_force;
48 
49 /*
50  * not really modular, but the easiest way to keep compat with existing
51  * bootargs behaviour is to continue using module_param here.
52  */
53 module_param(pciehp_debug, bool, 0644);
54 module_param(pciehp_poll_mode, bool, 0644);
55 module_param(pciehp_poll_time, int, 0644);
56 module_param(pciehp_force, bool, 0644);
57 MODULE_PARM_DESC(pciehp_debug, "Debugging mode enabled or not");
58 MODULE_PARM_DESC(pciehp_poll_mode, "Using polling mechanism for hot-plug events or not");
59 MODULE_PARM_DESC(pciehp_poll_time, "Polling mechanism frequency, in seconds");
60 MODULE_PARM_DESC(pciehp_force, "Force pciehp, even if OSHP is missing");
61 
62 #define PCIE_MODULE_NAME "pciehp"
63 
64 static int set_attention_status(struct hotplug_slot *slot, u8 value);
65 static int enable_slot(struct hotplug_slot *slot);
66 static int disable_slot(struct hotplug_slot *slot);
67 static int get_power_status(struct hotplug_slot *slot, u8 *value);
68 static int get_attention_status(struct hotplug_slot *slot, u8 *value);
69 static int get_latch_status(struct hotplug_slot *slot, u8 *value);
70 static int get_adapter_status(struct hotplug_slot *slot, u8 *value);
71 static int reset_slot(struct hotplug_slot *slot, int probe);
72 
73 /**
74  * release_slot - free up the memory used by a slot
75  * @hotplug_slot: slot to free
76  */
77 static void release_slot(struct hotplug_slot *hotplug_slot)
78 {
79 	kfree(hotplug_slot->ops);
80 	kfree(hotplug_slot->info);
81 	kfree(hotplug_slot);
82 }
83 
84 static int init_slot(struct controller *ctrl)
85 {
86 	struct slot *slot = ctrl->slot;
87 	struct hotplug_slot *hotplug = NULL;
88 	struct hotplug_slot_info *info = NULL;
89 	struct hotplug_slot_ops *ops = NULL;
90 	char name[SLOT_NAME_SIZE];
91 	int retval = -ENOMEM;
92 
93 	hotplug = kzalloc(sizeof(*hotplug), GFP_KERNEL);
94 	if (!hotplug)
95 		goto out;
96 
97 	info = kzalloc(sizeof(*info), GFP_KERNEL);
98 	if (!info)
99 		goto out;
100 
101 	/* Setup hotplug slot ops */
102 	ops = kzalloc(sizeof(*ops), GFP_KERNEL);
103 	if (!ops)
104 		goto out;
105 
106 	ops->enable_slot = enable_slot;
107 	ops->disable_slot = disable_slot;
108 	ops->get_power_status = get_power_status;
109 	ops->get_adapter_status = get_adapter_status;
110 	ops->reset_slot = reset_slot;
111 	if (MRL_SENS(ctrl))
112 		ops->get_latch_status = get_latch_status;
113 	if (ATTN_LED(ctrl)) {
114 		ops->get_attention_status = get_attention_status;
115 		ops->set_attention_status = set_attention_status;
116 	} else if (ctrl->pcie->port->hotplug_user_indicators) {
117 		ops->get_attention_status = pciehp_get_raw_indicator_status;
118 		ops->set_attention_status = pciehp_set_raw_indicator_status;
119 	}
120 
121 	/* register this slot with the hotplug pci core */
122 	hotplug->info = info;
123 	hotplug->private = slot;
124 	hotplug->release = &release_slot;
125 	hotplug->ops = ops;
126 	slot->hotplug_slot = hotplug;
127 	snprintf(name, SLOT_NAME_SIZE, "%u", PSN(ctrl));
128 
129 	retval = pci_hp_register(hotplug,
130 				 ctrl->pcie->port->subordinate, 0, name);
131 	if (retval)
132 		ctrl_err(ctrl, "pci_hp_register failed: error %d\n", retval);
133 out:
134 	if (retval) {
135 		kfree(ops);
136 		kfree(info);
137 		kfree(hotplug);
138 	}
139 	return retval;
140 }
141 
142 static void cleanup_slot(struct controller *ctrl)
143 {
144 	pci_hp_deregister(ctrl->slot->hotplug_slot);
145 }
146 
147 /*
148  * set_attention_status - Turns the Amber LED for a slot on, off or blink
149  */
150 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
151 {
152 	struct slot *slot = hotplug_slot->private;
153 
154 	pciehp_set_attention_status(slot, status);
155 	return 0;
156 }
157 
158 
159 static int enable_slot(struct hotplug_slot *hotplug_slot)
160 {
161 	struct slot *slot = hotplug_slot->private;
162 
163 	return pciehp_sysfs_enable_slot(slot);
164 }
165 
166 
167 static int disable_slot(struct hotplug_slot *hotplug_slot)
168 {
169 	struct slot *slot = hotplug_slot->private;
170 
171 	return pciehp_sysfs_disable_slot(slot);
172 }
173 
174 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
175 {
176 	struct slot *slot = hotplug_slot->private;
177 
178 	pciehp_get_power_status(slot, value);
179 	return 0;
180 }
181 
182 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
183 {
184 	struct slot *slot = hotplug_slot->private;
185 
186 	pciehp_get_attention_status(slot, value);
187 	return 0;
188 }
189 
190 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
191 {
192 	struct slot *slot = hotplug_slot->private;
193 
194 	pciehp_get_latch_status(slot, value);
195 	return 0;
196 }
197 
198 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
199 {
200 	struct slot *slot = hotplug_slot->private;
201 
202 	pciehp_get_adapter_status(slot, value);
203 	return 0;
204 }
205 
206 static int reset_slot(struct hotplug_slot *hotplug_slot, int probe)
207 {
208 	struct slot *slot = hotplug_slot->private;
209 
210 	return pciehp_reset_slot(slot, probe);
211 }
212 
213 static int pciehp_probe(struct pcie_device *dev)
214 {
215 	int rc;
216 	struct controller *ctrl;
217 	struct slot *slot;
218 	u8 occupied, poweron;
219 
220 	/* If this is not a "hotplug" service, we have no business here. */
221 	if (dev->service != PCIE_PORT_SERVICE_HP)
222 		return -ENODEV;
223 
224 	if (!dev->port->subordinate) {
225 		/* Can happen if we run out of bus numbers during probe */
226 		dev_err(&dev->device,
227 			"Hotplug bridge without secondary bus, ignoring\n");
228 		return -ENODEV;
229 	}
230 
231 	ctrl = pcie_init(dev);
232 	if (!ctrl) {
233 		dev_err(&dev->device, "Controller initialization failed\n");
234 		return -ENODEV;
235 	}
236 	set_service_data(dev, ctrl);
237 
238 	/* Setup the slot information structures */
239 	rc = init_slot(ctrl);
240 	if (rc) {
241 		if (rc == -EBUSY)
242 			ctrl_warn(ctrl, "Slot already registered by another hotplug driver\n");
243 		else
244 			ctrl_err(ctrl, "Slot initialization failed (%d)\n", rc);
245 		goto err_out_release_ctlr;
246 	}
247 
248 	/* Enable events after we have setup the data structures */
249 	rc = pcie_init_notification(ctrl);
250 	if (rc) {
251 		ctrl_err(ctrl, "Notification initialization failed (%d)\n", rc);
252 		goto err_out_free_ctrl_slot;
253 	}
254 
255 	/* Check if slot is occupied */
256 	slot = ctrl->slot;
257 	pciehp_get_adapter_status(slot, &occupied);
258 	pciehp_get_power_status(slot, &poweron);
259 	if (occupied && pciehp_force) {
260 		mutex_lock(&slot->hotplug_lock);
261 		pciehp_enable_slot(slot);
262 		mutex_unlock(&slot->hotplug_lock);
263 	}
264 	/* If empty slot's power status is on, turn power off */
265 	if (!occupied && poweron && POWER_CTRL(ctrl))
266 		pciehp_power_off_slot(slot);
267 
268 	return 0;
269 
270 err_out_free_ctrl_slot:
271 	cleanup_slot(ctrl);
272 err_out_release_ctlr:
273 	pciehp_release_ctrl(ctrl);
274 	return -ENODEV;
275 }
276 
277 static void pciehp_remove(struct pcie_device *dev)
278 {
279 	struct controller *ctrl = get_service_data(dev);
280 
281 	cleanup_slot(ctrl);
282 	pciehp_release_ctrl(ctrl);
283 }
284 
285 #ifdef CONFIG_PM
286 static int pciehp_suspend(struct pcie_device *dev)
287 {
288 	return 0;
289 }
290 
291 static int pciehp_resume(struct pcie_device *dev)
292 {
293 	struct controller *ctrl;
294 	struct slot *slot;
295 	u8 status;
296 
297 	ctrl = get_service_data(dev);
298 
299 	/* reinitialize the chipset's event detection logic */
300 	pcie_enable_notification(ctrl);
301 
302 	slot = ctrl->slot;
303 
304 	/* Check if slot is occupied */
305 	pciehp_get_adapter_status(slot, &status);
306 	mutex_lock(&slot->hotplug_lock);
307 	if (status)
308 		pciehp_enable_slot(slot);
309 	else
310 		pciehp_disable_slot(slot);
311 	mutex_unlock(&slot->hotplug_lock);
312 	return 0;
313 }
314 #endif /* PM */
315 
316 static struct pcie_port_service_driver hpdriver_portdrv = {
317 	.name		= PCIE_MODULE_NAME,
318 	.port_type	= PCIE_ANY_PORT,
319 	.service	= PCIE_PORT_SERVICE_HP,
320 
321 	.probe		= pciehp_probe,
322 	.remove		= pciehp_remove,
323 
324 #ifdef	CONFIG_PM
325 	.suspend	= pciehp_suspend,
326 	.resume		= pciehp_resume,
327 #endif	/* PM */
328 };
329 
330 static int __init pcied_init(void)
331 {
332 	int retval = 0;
333 
334 	retval = pcie_port_service_register(&hpdriver_portdrv);
335 	dbg("pcie_port_service_register = %d\n", retval);
336 	if (retval)
337 		dbg("Failure to register service\n");
338 
339 	return retval;
340 }
341 device_initcall(pcied_init);
342