xref: /linux/drivers/pci/hotplug/shpchp_core.c (revision 3a39d672e7f48b8d6b91a09afa4b55352773b4b5)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Standard 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  */
15 
16 #include <linux/module.h>
17 #include <linux/moduleparam.h>
18 #include <linux/kernel.h>
19 #include <linux/types.h>
20 #include <linux/slab.h>
21 #include <linux/pci.h>
22 #include "shpchp.h"
23 
24 /* Global variables */
25 bool shpchp_debug;
26 bool shpchp_poll_mode;
27 int shpchp_poll_time;
28 
29 #define DRIVER_VERSION	"0.4"
30 #define DRIVER_AUTHOR	"Dan Zink <dan.zink@compaq.com>, Greg Kroah-Hartman <greg@kroah.com>, Dely Sy <dely.l.sy@intel.com>"
31 #define DRIVER_DESC	"Standard Hot Plug PCI Controller Driver"
32 
33 MODULE_AUTHOR(DRIVER_AUTHOR);
34 MODULE_DESCRIPTION(DRIVER_DESC);
35 
36 module_param(shpchp_debug, bool, 0644);
37 module_param(shpchp_poll_mode, bool, 0644);
38 module_param(shpchp_poll_time, int, 0644);
39 MODULE_PARM_DESC(shpchp_debug, "Debugging mode enabled or not");
40 MODULE_PARM_DESC(shpchp_poll_mode, "Using polling mechanism for hot-plug events or not");
41 MODULE_PARM_DESC(shpchp_poll_time, "Polling mechanism frequency, in seconds");
42 
43 #define SHPC_MODULE_NAME "shpchp"
44 
45 static int set_attention_status(struct hotplug_slot *slot, u8 value);
46 static int enable_slot(struct hotplug_slot *slot);
47 static int disable_slot(struct hotplug_slot *slot);
48 static int get_power_status(struct hotplug_slot *slot, u8 *value);
49 static int get_attention_status(struct hotplug_slot *slot, u8 *value);
50 static int get_latch_status(struct hotplug_slot *slot, u8 *value);
51 static int get_adapter_status(struct hotplug_slot *slot, u8 *value);
52 
53 static const struct hotplug_slot_ops shpchp_hotplug_slot_ops = {
54 	.set_attention_status =	set_attention_status,
55 	.enable_slot =		enable_slot,
56 	.disable_slot =		disable_slot,
57 	.get_power_status =	get_power_status,
58 	.get_attention_status =	get_attention_status,
59 	.get_latch_status =	get_latch_status,
60 	.get_adapter_status =	get_adapter_status,
61 };
62 
init_slots(struct controller * ctrl)63 static int init_slots(struct controller *ctrl)
64 {
65 	struct slot *slot;
66 	struct hotplug_slot *hotplug_slot;
67 	char name[SLOT_NAME_SIZE];
68 	int retval;
69 	int i;
70 
71 	for (i = 0; i < ctrl->num_slots; i++) {
72 		slot = kzalloc(sizeof(*slot), GFP_KERNEL);
73 		if (!slot) {
74 			retval = -ENOMEM;
75 			goto error;
76 		}
77 
78 		hotplug_slot = &slot->hotplug_slot;
79 
80 		slot->hp_slot = i;
81 		slot->ctrl = ctrl;
82 		slot->bus = ctrl->pci_dev->subordinate->number;
83 		slot->device = ctrl->slot_device_offset + i;
84 		slot->number = ctrl->first_slot + (ctrl->slot_num_inc * i);
85 
86 		slot->wq = alloc_workqueue("shpchp-%d", 0, 0, slot->number);
87 		if (!slot->wq) {
88 			retval = -ENOMEM;
89 			goto error_slot;
90 		}
91 
92 		mutex_init(&slot->lock);
93 		INIT_DELAYED_WORK(&slot->work, shpchp_queue_pushbutton_work);
94 
95 		/* register this slot with the hotplug pci core */
96 		snprintf(name, SLOT_NAME_SIZE, "%d", slot->number);
97 		hotplug_slot->ops = &shpchp_hotplug_slot_ops;
98 
99 		ctrl_dbg(ctrl, "Registering domain:bus:dev=%04x:%02x:%02x hp_slot=%x sun=%x slot_device_offset=%x\n",
100 			 pci_domain_nr(ctrl->pci_dev->subordinate),
101 			 slot->bus, slot->device, slot->hp_slot, slot->number,
102 			 ctrl->slot_device_offset);
103 		retval = pci_hp_register(hotplug_slot,
104 				ctrl->pci_dev->subordinate, slot->device, name);
105 		if (retval) {
106 			ctrl_err(ctrl, "pci_hp_register failed with error %d\n",
107 				 retval);
108 			goto error_slotwq;
109 		}
110 
111 		get_power_status(hotplug_slot, &slot->pwr_save);
112 		get_attention_status(hotplug_slot, &slot->attention_save);
113 		get_latch_status(hotplug_slot, &slot->latch_save);
114 		get_adapter_status(hotplug_slot, &slot->presence_save);
115 
116 		list_add(&slot->slot_list, &ctrl->slot_list);
117 	}
118 
119 	return 0;
120 error_slotwq:
121 	destroy_workqueue(slot->wq);
122 error_slot:
123 	kfree(slot);
124 error:
125 	return retval;
126 }
127 
cleanup_slots(struct controller * ctrl)128 void cleanup_slots(struct controller *ctrl)
129 {
130 	struct slot *slot, *next;
131 
132 	list_for_each_entry_safe(slot, next, &ctrl->slot_list, slot_list) {
133 		list_del(&slot->slot_list);
134 		cancel_delayed_work(&slot->work);
135 		destroy_workqueue(slot->wq);
136 		pci_hp_deregister(&slot->hotplug_slot);
137 		kfree(slot);
138 	}
139 }
140 
141 /*
142  * set_attention_status - Turns the Amber LED for a slot on, off or blink
143  */
set_attention_status(struct hotplug_slot * hotplug_slot,u8 status)144 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
145 {
146 	struct slot *slot = get_slot(hotplug_slot);
147 
148 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
149 		 __func__, slot_name(slot));
150 
151 	slot->attention_save = status;
152 	shpchp_set_attention_status(slot, status);
153 
154 	return 0;
155 }
156 
enable_slot(struct hotplug_slot * hotplug_slot)157 static int enable_slot(struct hotplug_slot *hotplug_slot)
158 {
159 	struct slot *slot = get_slot(hotplug_slot);
160 
161 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
162 		 __func__, slot_name(slot));
163 
164 	return shpchp_sysfs_enable_slot(slot);
165 }
166 
disable_slot(struct hotplug_slot * hotplug_slot)167 static int disable_slot(struct hotplug_slot *hotplug_slot)
168 {
169 	struct slot *slot = get_slot(hotplug_slot);
170 
171 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
172 		 __func__, slot_name(slot));
173 
174 	return shpchp_sysfs_disable_slot(slot);
175 }
176 
get_power_status(struct hotplug_slot * hotplug_slot,u8 * value)177 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
178 {
179 	struct slot *slot = get_slot(hotplug_slot);
180 	int retval;
181 
182 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
183 		 __func__, slot_name(slot));
184 
185 	retval = shpchp_get_power_status(slot, value);
186 	if (retval < 0)
187 		*value = slot->pwr_save;
188 
189 	return 0;
190 }
191 
get_attention_status(struct hotplug_slot * hotplug_slot,u8 * value)192 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
193 {
194 	struct slot *slot = get_slot(hotplug_slot);
195 	int retval;
196 
197 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
198 		 __func__, slot_name(slot));
199 
200 	retval = shpchp_get_attention_status(slot, value);
201 	if (retval < 0)
202 		*value = slot->attention_save;
203 
204 	return 0;
205 }
206 
get_latch_status(struct hotplug_slot * hotplug_slot,u8 * value)207 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
208 {
209 	struct slot *slot = get_slot(hotplug_slot);
210 	int retval;
211 
212 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
213 		 __func__, slot_name(slot));
214 
215 	retval = shpchp_get_latch_status(slot, value);
216 	if (retval < 0)
217 		*value = slot->latch_save;
218 
219 	return 0;
220 }
221 
get_adapter_status(struct hotplug_slot * hotplug_slot,u8 * value)222 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
223 {
224 	struct slot *slot = get_slot(hotplug_slot);
225 	int retval;
226 
227 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
228 		 __func__, slot_name(slot));
229 
230 	retval = shpchp_get_adapter_status(slot, value);
231 	if (retval < 0)
232 		*value = slot->presence_save;
233 
234 	return 0;
235 }
236 
shpc_capable(struct pci_dev * bridge)237 static bool shpc_capable(struct pci_dev *bridge)
238 {
239 	/*
240 	 * It is assumed that AMD GOLAM chips support SHPC but they do not
241 	 * have SHPC capability.
242 	 */
243 	if (bridge->vendor == PCI_VENDOR_ID_AMD &&
244 	    bridge->device == PCI_DEVICE_ID_AMD_GOLAM_7450)
245 		return true;
246 
247 	if (pci_find_capability(bridge, PCI_CAP_ID_SHPC))
248 		return true;
249 
250 	return false;
251 }
252 
shpc_probe(struct pci_dev * pdev,const struct pci_device_id * ent)253 static int shpc_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
254 {
255 	int rc;
256 	struct controller *ctrl;
257 
258 	if (!shpc_capable(pdev))
259 		return -ENODEV;
260 
261 	if (acpi_get_hp_hw_control_from_firmware(pdev))
262 		return -ENODEV;
263 
264 	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
265 	if (!ctrl)
266 		goto err_out_none;
267 
268 	INIT_LIST_HEAD(&ctrl->slot_list);
269 
270 	rc = shpc_init(ctrl, pdev);
271 	if (rc) {
272 		ctrl_dbg(ctrl, "Controller initialization failed\n");
273 		goto err_out_free_ctrl;
274 	}
275 
276 	pci_set_drvdata(pdev, ctrl);
277 
278 	/* Setup the slot information structures */
279 	rc = init_slots(ctrl);
280 	if (rc) {
281 		ctrl_err(ctrl, "Slot initialization failed\n");
282 		goto err_out_release_ctlr;
283 	}
284 
285 	rc = shpchp_create_ctrl_files(ctrl);
286 	if (rc)
287 		goto err_cleanup_slots;
288 
289 	pdev->shpc_managed = 1;
290 	return 0;
291 
292 err_cleanup_slots:
293 	cleanup_slots(ctrl);
294 err_out_release_ctlr:
295 	shpchp_release_ctlr(ctrl);
296 err_out_free_ctrl:
297 	kfree(ctrl);
298 err_out_none:
299 	return -ENODEV;
300 }
301 
shpc_remove(struct pci_dev * dev)302 static void shpc_remove(struct pci_dev *dev)
303 {
304 	struct controller *ctrl = pci_get_drvdata(dev);
305 
306 	dev->shpc_managed = 0;
307 	shpchp_remove_ctrl_files(ctrl);
308 	shpchp_release_ctlr(ctrl);
309 	kfree(ctrl);
310 }
311 
312 static const struct pci_device_id shpcd_pci_tbl[] = {
313 	{PCI_DEVICE_CLASS(PCI_CLASS_BRIDGE_PCI_NORMAL, ~0)},
314 	{ /* end: all zeroes */ }
315 };
316 MODULE_DEVICE_TABLE(pci, shpcd_pci_tbl);
317 
318 static struct pci_driver shpc_driver = {
319 	.name =		SHPC_MODULE_NAME,
320 	.id_table =	shpcd_pci_tbl,
321 	.probe =	shpc_probe,
322 	.remove =	shpc_remove,
323 };
324 
shpcd_init(void)325 static int __init shpcd_init(void)
326 {
327 	int retval;
328 
329 	retval = pci_register_driver(&shpc_driver);
330 	dbg("%s: pci_register_driver = %d\n", __func__, retval);
331 	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
332 
333 	return retval;
334 }
335 
shpcd_cleanup(void)336 static void __exit shpcd_cleanup(void)
337 {
338 	dbg("unload_shpchpd()\n");
339 	pci_unregister_driver(&shpc_driver);
340 	info(DRIVER_DESC " version: " DRIVER_VERSION " unloaded\n");
341 }
342 
343 module_init(shpcd_init);
344 module_exit(shpcd_cleanup);
345