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