1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * PCI Express Hot Plug Controller Driver
4  *
5  * Copyright (C) 1995,2001 Compaq Computer Corporation
6  * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
7  * Copyright (C) 2001 IBM Corp.
8  * Copyright (C) 2003-2004 Intel Corporation
9  *
10  * All rights reserved.
11  *
12  * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
13  *
14  * Authors:
15  *   Dan Zink <dan.zink@compaq.com>
16  *   Greg Kroah-Hartman <greg@kroah.com>
17  *   Dely Sy <dely.l.sy@intel.com>"
18  */
19 
20 #include <linux/moduleparam.h>
21 #include <linux/kernel.h>
22 #include <linux/slab.h>
23 #include <linux/types.h>
24 #include <linux/pci.h>
25 #include "pciehp.h"
26 #include <linux/interrupt.h>
27 #include <linux/time.h>
28 
29 /* Global variables */
30 bool pciehp_debug;
31 bool pciehp_poll_mode;
32 int pciehp_poll_time;
33 static bool pciehp_force;
34 
35 /*
36  * not really modular, but the easiest way to keep compat with existing
37  * bootargs behaviour is to continue using module_param here.
38  */
39 module_param(pciehp_debug, bool, 0644);
40 module_param(pciehp_poll_mode, bool, 0644);
41 module_param(pciehp_poll_time, int, 0644);
42 module_param(pciehp_force, bool, 0644);
43 MODULE_PARM_DESC(pciehp_debug, "Debugging mode enabled or not");
44 MODULE_PARM_DESC(pciehp_poll_mode, "Using polling mechanism for hot-plug events or not");
45 MODULE_PARM_DESC(pciehp_poll_time, "Polling mechanism frequency, in seconds");
46 MODULE_PARM_DESC(pciehp_force, "Force pciehp, even if OSHP is missing");
47 
48 #define PCIE_MODULE_NAME "pciehp"
49 
50 static int set_attention_status(struct hotplug_slot *slot, u8 value);
51 static int enable_slot(struct hotplug_slot *slot);
52 static int disable_slot(struct hotplug_slot *slot);
53 static int get_power_status(struct hotplug_slot *slot, u8 *value);
54 static int get_attention_status(struct hotplug_slot *slot, u8 *value);
55 static int get_latch_status(struct hotplug_slot *slot, u8 *value);
56 static int get_adapter_status(struct hotplug_slot *slot, u8 *value);
57 static int reset_slot(struct hotplug_slot *slot, int probe);
58 
59 /**
60  * release_slot - free up the memory used by a slot
61  * @hotplug_slot: slot to free
62  */
63 static void release_slot(struct hotplug_slot *hotplug_slot)
64 {
65 	kfree(hotplug_slot->ops);
66 	kfree(hotplug_slot->info);
67 	kfree(hotplug_slot);
68 }
69 
70 static int init_slot(struct controller *ctrl)
71 {
72 	struct slot *slot = ctrl->slot;
73 	struct hotplug_slot *hotplug = NULL;
74 	struct hotplug_slot_info *info = NULL;
75 	struct hotplug_slot_ops *ops = NULL;
76 	char name[SLOT_NAME_SIZE];
77 	int retval = -ENOMEM;
78 
79 	hotplug = kzalloc(sizeof(*hotplug), GFP_KERNEL);
80 	if (!hotplug)
81 		goto out;
82 
83 	info = kzalloc(sizeof(*info), GFP_KERNEL);
84 	if (!info)
85 		goto out;
86 
87 	/* Setup hotplug slot ops */
88 	ops = kzalloc(sizeof(*ops), GFP_KERNEL);
89 	if (!ops)
90 		goto out;
91 
92 	ops->enable_slot = enable_slot;
93 	ops->disable_slot = disable_slot;
94 	ops->get_power_status = get_power_status;
95 	ops->get_adapter_status = get_adapter_status;
96 	ops->reset_slot = reset_slot;
97 	if (MRL_SENS(ctrl))
98 		ops->get_latch_status = get_latch_status;
99 	if (ATTN_LED(ctrl)) {
100 		ops->get_attention_status = get_attention_status;
101 		ops->set_attention_status = set_attention_status;
102 	} else if (ctrl->pcie->port->hotplug_user_indicators) {
103 		ops->get_attention_status = pciehp_get_raw_indicator_status;
104 		ops->set_attention_status = pciehp_set_raw_indicator_status;
105 	}
106 
107 	/* register this slot with the hotplug pci core */
108 	hotplug->info = info;
109 	hotplug->private = slot;
110 	hotplug->release = &release_slot;
111 	hotplug->ops = ops;
112 	slot->hotplug_slot = hotplug;
113 	snprintf(name, SLOT_NAME_SIZE, "%u", PSN(ctrl));
114 
115 	retval = pci_hp_register(hotplug,
116 				 ctrl->pcie->port->subordinate, 0, name);
117 	if (retval)
118 		ctrl_err(ctrl, "pci_hp_register failed: error %d\n", retval);
119 out:
120 	if (retval) {
121 		kfree(ops);
122 		kfree(info);
123 		kfree(hotplug);
124 	}
125 	return retval;
126 }
127 
128 static void cleanup_slot(struct controller *ctrl)
129 {
130 	pci_hp_deregister(ctrl->slot->hotplug_slot);
131 }
132 
133 /*
134  * set_attention_status - Turns the Amber LED for a slot on, off or blink
135  */
136 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
137 {
138 	struct slot *slot = hotplug_slot->private;
139 
140 	pciehp_set_attention_status(slot, status);
141 	return 0;
142 }
143 
144 
145 static int enable_slot(struct hotplug_slot *hotplug_slot)
146 {
147 	struct slot *slot = hotplug_slot->private;
148 
149 	return pciehp_sysfs_enable_slot(slot);
150 }
151 
152 
153 static int disable_slot(struct hotplug_slot *hotplug_slot)
154 {
155 	struct slot *slot = hotplug_slot->private;
156 
157 	return pciehp_sysfs_disable_slot(slot);
158 }
159 
160 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
161 {
162 	struct slot *slot = hotplug_slot->private;
163 
164 	pciehp_get_power_status(slot, value);
165 	return 0;
166 }
167 
168 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
169 {
170 	struct slot *slot = hotplug_slot->private;
171 
172 	pciehp_get_attention_status(slot, value);
173 	return 0;
174 }
175 
176 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
177 {
178 	struct slot *slot = hotplug_slot->private;
179 
180 	pciehp_get_latch_status(slot, value);
181 	return 0;
182 }
183 
184 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
185 {
186 	struct slot *slot = hotplug_slot->private;
187 
188 	pciehp_get_adapter_status(slot, value);
189 	return 0;
190 }
191 
192 static int reset_slot(struct hotplug_slot *hotplug_slot, int probe)
193 {
194 	struct slot *slot = hotplug_slot->private;
195 
196 	return pciehp_reset_slot(slot, probe);
197 }
198 
199 static int pciehp_probe(struct pcie_device *dev)
200 {
201 	int rc;
202 	struct controller *ctrl;
203 	struct slot *slot;
204 	u8 occupied, poweron;
205 
206 	/* If this is not a "hotplug" service, we have no business here. */
207 	if (dev->service != PCIE_PORT_SERVICE_HP)
208 		return -ENODEV;
209 
210 	if (!dev->port->subordinate) {
211 		/* Can happen if we run out of bus numbers during probe */
212 		dev_err(&dev->device,
213 			"Hotplug bridge without secondary bus, ignoring\n");
214 		return -ENODEV;
215 	}
216 
217 	ctrl = pcie_init(dev);
218 	if (!ctrl) {
219 		dev_err(&dev->device, "Controller initialization failed\n");
220 		return -ENODEV;
221 	}
222 	set_service_data(dev, ctrl);
223 
224 	/* Setup the slot information structures */
225 	rc = init_slot(ctrl);
226 	if (rc) {
227 		if (rc == -EBUSY)
228 			ctrl_warn(ctrl, "Slot already registered by another hotplug driver\n");
229 		else
230 			ctrl_err(ctrl, "Slot initialization failed (%d)\n", rc);
231 		goto err_out_release_ctlr;
232 	}
233 
234 	/* Enable events after we have setup the data structures */
235 	rc = pcie_init_notification(ctrl);
236 	if (rc) {
237 		ctrl_err(ctrl, "Notification initialization failed (%d)\n", rc);
238 		goto err_out_free_ctrl_slot;
239 	}
240 
241 	/* Check if slot is occupied */
242 	slot = ctrl->slot;
243 	pciehp_get_adapter_status(slot, &occupied);
244 	pciehp_get_power_status(slot, &poweron);
245 	if (occupied && pciehp_force) {
246 		mutex_lock(&slot->hotplug_lock);
247 		pciehp_enable_slot(slot);
248 		mutex_unlock(&slot->hotplug_lock);
249 	}
250 	/* If empty slot's power status is on, turn power off */
251 	if (!occupied && poweron && POWER_CTRL(ctrl))
252 		pciehp_power_off_slot(slot);
253 
254 	return 0;
255 
256 err_out_free_ctrl_slot:
257 	cleanup_slot(ctrl);
258 err_out_release_ctlr:
259 	pciehp_release_ctrl(ctrl);
260 	return -ENODEV;
261 }
262 
263 static void pciehp_remove(struct pcie_device *dev)
264 {
265 	struct controller *ctrl = get_service_data(dev);
266 
267 	cleanup_slot(ctrl);
268 	pciehp_release_ctrl(ctrl);
269 }
270 
271 #ifdef CONFIG_PM
272 static int pciehp_suspend(struct pcie_device *dev)
273 {
274 	return 0;
275 }
276 
277 static int pciehp_resume(struct pcie_device *dev)
278 {
279 	struct controller *ctrl;
280 	struct slot *slot;
281 	u8 status;
282 
283 	ctrl = get_service_data(dev);
284 
285 	/* reinitialize the chipset's event detection logic */
286 	pcie_reenable_notification(ctrl);
287 
288 	slot = ctrl->slot;
289 
290 	/* Check if slot is occupied */
291 	pciehp_get_adapter_status(slot, &status);
292 	mutex_lock(&slot->hotplug_lock);
293 	if (status)
294 		pciehp_enable_slot(slot);
295 	else
296 		pciehp_disable_slot(slot);
297 	mutex_unlock(&slot->hotplug_lock);
298 	return 0;
299 }
300 #endif /* PM */
301 
302 static struct pcie_port_service_driver hpdriver_portdrv = {
303 	.name		= PCIE_MODULE_NAME,
304 	.port_type	= PCIE_ANY_PORT,
305 	.service	= PCIE_PORT_SERVICE_HP,
306 
307 	.probe		= pciehp_probe,
308 	.remove		= pciehp_remove,
309 
310 #ifdef	CONFIG_PM
311 	.suspend	= pciehp_suspend,
312 	.resume		= pciehp_resume,
313 #endif	/* PM */
314 };
315 
316 static int __init pcied_init(void)
317 {
318 	int retval = 0;
319 
320 	retval = pcie_port_service_register(&hpdriver_portdrv);
321 	dbg("pcie_port_service_register = %d\n", retval);
322 	if (retval)
323 		dbg("Failure to register service\n");
324 
325 	return retval;
326 }
327 device_initcall(pcied_init);
328