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 MODULE_LICENSE("GPL");
36 
37 module_param(shpchp_debug, bool, 0644);
38 module_param(shpchp_poll_mode, bool, 0644);
39 module_param(shpchp_poll_time, int, 0644);
40 MODULE_PARM_DESC(shpchp_debug, "Debugging mode enabled or not");
41 MODULE_PARM_DESC(shpchp_poll_mode, "Using polling mechanism for hot-plug events or not");
42 MODULE_PARM_DESC(shpchp_poll_time, "Polling mechanism frequency, in seconds");
43 
44 #define SHPC_MODULE_NAME "shpchp"
45 
46 static int set_attention_status(struct hotplug_slot *slot, u8 value);
47 static int enable_slot(struct hotplug_slot *slot);
48 static int disable_slot(struct hotplug_slot *slot);
49 static int get_power_status(struct hotplug_slot *slot, u8 *value);
50 static int get_attention_status(struct hotplug_slot *slot, u8 *value);
51 static int get_latch_status(struct hotplug_slot *slot, u8 *value);
52 static int get_adapter_status(struct hotplug_slot *slot, u8 *value);
53 
54 static struct hotplug_slot_ops shpchp_hotplug_slot_ops = {
55 	.set_attention_status =	set_attention_status,
56 	.enable_slot =		enable_slot,
57 	.disable_slot =		disable_slot,
58 	.get_power_status =	get_power_status,
59 	.get_attention_status =	get_attention_status,
60 	.get_latch_status =	get_latch_status,
61 	.get_adapter_status =	get_adapter_status,
62 };
63 
init_slots(struct controller * ctrl)64 static int init_slots(struct controller *ctrl)
65 {
66 	struct slot *slot;
67 	struct hotplug_slot *hotplug_slot;
68 	struct hotplug_slot_info *info;
69 	char name[SLOT_NAME_SIZE];
70 	int retval;
71 	int i;
72 
73 	for (i = 0; i < ctrl->num_slots; i++) {
74 		slot = kzalloc(sizeof(*slot), GFP_KERNEL);
75 		if (!slot) {
76 			retval = -ENOMEM;
77 			goto error;
78 		}
79 
80 		hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL);
81 		if (!hotplug_slot) {
82 			retval = -ENOMEM;
83 			goto error_slot;
84 		}
85 		slot->hotplug_slot = hotplug_slot;
86 
87 		info = kzalloc(sizeof(*info), GFP_KERNEL);
88 		if (!info) {
89 			retval = -ENOMEM;
90 			goto error_hpslot;
91 		}
92 		hotplug_slot->info = info;
93 
94 		slot->hp_slot = i;
95 		slot->ctrl = ctrl;
96 		slot->bus = ctrl->pci_dev->subordinate->number;
97 		slot->device = ctrl->slot_device_offset + i;
98 		slot->hpc_ops = ctrl->hpc_ops;
99 		slot->number = ctrl->first_slot + (ctrl->slot_num_inc * i);
100 
101 		slot->wq = alloc_workqueue("shpchp-%d", 0, 0, slot->number);
102 		if (!slot->wq) {
103 			retval = -ENOMEM;
104 			goto error_info;
105 		}
106 
107 		mutex_init(&slot->lock);
108 		INIT_DELAYED_WORK(&slot->work, shpchp_queue_pushbutton_work);
109 
110 		/* register this slot with the hotplug pci core */
111 		hotplug_slot->private = slot;
112 		snprintf(name, SLOT_NAME_SIZE, "%d", slot->number);
113 		hotplug_slot->ops = &shpchp_hotplug_slot_ops;
114 
115 		ctrl_dbg(ctrl, "Registering domain:bus:dev=%04x:%02x:%02x hp_slot=%x sun=%x slot_device_offset=%x\n",
116 			 pci_domain_nr(ctrl->pci_dev->subordinate),
117 			 slot->bus, slot->device, slot->hp_slot, slot->number,
118 			 ctrl->slot_device_offset);
119 		retval = pci_hp_register(slot->hotplug_slot,
120 				ctrl->pci_dev->subordinate, slot->device, name);
121 		if (retval) {
122 			ctrl_err(ctrl, "pci_hp_register failed with error %d\n",
123 				 retval);
124 			goto error_slotwq;
125 		}
126 
127 		get_power_status(hotplug_slot, &info->power_status);
128 		get_attention_status(hotplug_slot, &info->attention_status);
129 		get_latch_status(hotplug_slot, &info->latch_status);
130 		get_adapter_status(hotplug_slot, &info->adapter_status);
131 
132 		list_add(&slot->slot_list, &ctrl->slot_list);
133 	}
134 
135 	return 0;
136 error_slotwq:
137 	destroy_workqueue(slot->wq);
138 error_info:
139 	kfree(info);
140 error_hpslot:
141 	kfree(hotplug_slot);
142 error_slot:
143 	kfree(slot);
144 error:
145 	return retval;
146 }
147 
cleanup_slots(struct controller * ctrl)148 void cleanup_slots(struct controller *ctrl)
149 {
150 	struct slot *slot, *next;
151 
152 	list_for_each_entry_safe(slot, next, &ctrl->slot_list, slot_list) {
153 		list_del(&slot->slot_list);
154 		cancel_delayed_work(&slot->work);
155 		destroy_workqueue(slot->wq);
156 		pci_hp_deregister(slot->hotplug_slot);
157 		kfree(slot->hotplug_slot->info);
158 		kfree(slot->hotplug_slot);
159 		kfree(slot);
160 	}
161 }
162 
163 /*
164  * set_attention_status - Turns the Amber LED for a slot on, off or blink
165  */
set_attention_status(struct hotplug_slot * hotplug_slot,u8 status)166 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
167 {
168 	struct slot *slot = get_slot(hotplug_slot);
169 
170 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
171 		 __func__, slot_name(slot));
172 
173 	hotplug_slot->info->attention_status = status;
174 	slot->hpc_ops->set_attention_status(slot, status);
175 
176 	return 0;
177 }
178 
enable_slot(struct hotplug_slot * hotplug_slot)179 static int enable_slot(struct hotplug_slot *hotplug_slot)
180 {
181 	struct slot *slot = get_slot(hotplug_slot);
182 
183 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
184 		 __func__, slot_name(slot));
185 
186 	return shpchp_sysfs_enable_slot(slot);
187 }
188 
disable_slot(struct hotplug_slot * hotplug_slot)189 static int disable_slot(struct hotplug_slot *hotplug_slot)
190 {
191 	struct slot *slot = get_slot(hotplug_slot);
192 
193 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
194 		 __func__, slot_name(slot));
195 
196 	return shpchp_sysfs_disable_slot(slot);
197 }
198 
get_power_status(struct hotplug_slot * hotplug_slot,u8 * value)199 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
200 {
201 	struct slot *slot = get_slot(hotplug_slot);
202 	int retval;
203 
204 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
205 		 __func__, slot_name(slot));
206 
207 	retval = slot->hpc_ops->get_power_status(slot, value);
208 	if (retval < 0)
209 		*value = hotplug_slot->info->power_status;
210 
211 	return 0;
212 }
213 
get_attention_status(struct hotplug_slot * hotplug_slot,u8 * value)214 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
215 {
216 	struct slot *slot = get_slot(hotplug_slot);
217 	int retval;
218 
219 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
220 		 __func__, slot_name(slot));
221 
222 	retval = slot->hpc_ops->get_attention_status(slot, value);
223 	if (retval < 0)
224 		*value = hotplug_slot->info->attention_status;
225 
226 	return 0;
227 }
228 
get_latch_status(struct hotplug_slot * hotplug_slot,u8 * value)229 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
230 {
231 	struct slot *slot = get_slot(hotplug_slot);
232 	int retval;
233 
234 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
235 		 __func__, slot_name(slot));
236 
237 	retval = slot->hpc_ops->get_latch_status(slot, value);
238 	if (retval < 0)
239 		*value = hotplug_slot->info->latch_status;
240 
241 	return 0;
242 }
243 
get_adapter_status(struct hotplug_slot * hotplug_slot,u8 * value)244 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
245 {
246 	struct slot *slot = get_slot(hotplug_slot);
247 	int retval;
248 
249 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
250 		 __func__, slot_name(slot));
251 
252 	retval = slot->hpc_ops->get_adapter_status(slot, value);
253 	if (retval < 0)
254 		*value = hotplug_slot->info->adapter_status;
255 
256 	return 0;
257 }
258 
shpc_capable(struct pci_dev * bridge)259 static bool shpc_capable(struct pci_dev *bridge)
260 {
261 	/*
262 	 * It is assumed that AMD GOLAM chips support SHPC but they do not
263 	 * have SHPC capability.
264 	 */
265 	if (bridge->vendor == PCI_VENDOR_ID_AMD &&
266 	    bridge->device == PCI_DEVICE_ID_AMD_GOLAM_7450)
267 		return true;
268 
269 	if (pci_find_capability(bridge, PCI_CAP_ID_SHPC))
270 		return true;
271 
272 	return false;
273 }
274 
shpc_probe(struct pci_dev * pdev,const struct pci_device_id * ent)275 static int shpc_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
276 {
277 	int rc;
278 	struct controller *ctrl;
279 
280 	if (!shpc_capable(pdev))
281 		return -ENODEV;
282 
283 	if (acpi_get_hp_hw_control_from_firmware(pdev))
284 		return -ENODEV;
285 
286 	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
287 	if (!ctrl)
288 		goto err_out_none;
289 
290 	INIT_LIST_HEAD(&ctrl->slot_list);
291 
292 	rc = shpc_init(ctrl, pdev);
293 	if (rc) {
294 		ctrl_dbg(ctrl, "Controller initialization failed\n");
295 		goto err_out_free_ctrl;
296 	}
297 
298 	pci_set_drvdata(pdev, ctrl);
299 
300 	/* Setup the slot information structures */
301 	rc = init_slots(ctrl);
302 	if (rc) {
303 		ctrl_err(ctrl, "Slot initialization failed\n");
304 		goto err_out_release_ctlr;
305 	}
306 
307 	rc = shpchp_create_ctrl_files(ctrl);
308 	if (rc)
309 		goto err_cleanup_slots;
310 
311 	pdev->shpc_managed = 1;
312 	return 0;
313 
314 err_cleanup_slots:
315 	cleanup_slots(ctrl);
316 err_out_release_ctlr:
317 	ctrl->hpc_ops->release_ctlr(ctrl);
318 err_out_free_ctrl:
319 	kfree(ctrl);
320 err_out_none:
321 	return -ENODEV;
322 }
323 
shpc_remove(struct pci_dev * dev)324 static void shpc_remove(struct pci_dev *dev)
325 {
326 	struct controller *ctrl = pci_get_drvdata(dev);
327 
328 	dev->shpc_managed = 0;
329 	shpchp_remove_ctrl_files(ctrl);
330 	ctrl->hpc_ops->release_ctlr(ctrl);
331 	kfree(ctrl);
332 }
333 
334 static const struct pci_device_id shpcd_pci_tbl[] = {
335 	{PCI_DEVICE_CLASS(((PCI_CLASS_BRIDGE_PCI << 8) | 0x00), ~0)},
336 	{ /* end: all zeroes */ }
337 };
338 MODULE_DEVICE_TABLE(pci, shpcd_pci_tbl);
339 
340 static struct pci_driver shpc_driver = {
341 	.name =		SHPC_MODULE_NAME,
342 	.id_table =	shpcd_pci_tbl,
343 	.probe =	shpc_probe,
344 	.remove =	shpc_remove,
345 };
346 
shpcd_init(void)347 static int __init shpcd_init(void)
348 {
349 	int retval;
350 
351 	retval = pci_register_driver(&shpc_driver);
352 	dbg("%s: pci_register_driver = %d\n", __func__, retval);
353 	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
354 
355 	return retval;
356 }
357 
shpcd_cleanup(void)358 static void __exit shpcd_cleanup(void)
359 {
360 	dbg("unload_shpchpd()\n");
361 	pci_unregister_driver(&shpc_driver);
362 	info(DRIVER_DESC " version: " DRIVER_VERSION " unloaded\n");
363 }
364 
365 module_init(shpcd_init);
366 module_exit(shpcd_cleanup);
367