1 /*
2  * PCI glue for ISHTP provider device (ISH) driver
3  *
4  * Copyright (c) 2014-2016, Intel Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms and conditions of the GNU General Public License,
8  * version 2, as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13  * more details.
14  */
15 
16 #include <linux/module.h>
17 #include <linux/moduleparam.h>
18 #include <linux/kernel.h>
19 #include <linux/device.h>
20 #include <linux/fs.h>
21 #include <linux/errno.h>
22 #include <linux/types.h>
23 #include <linux/pci.h>
24 #include <linux/sched.h>
25 #include <linux/interrupt.h>
26 #include <linux/workqueue.h>
27 #define CREATE_TRACE_POINTS
28 #include <trace/events/intel_ish.h>
29 #include "ishtp-dev.h"
30 #include "hw-ish.h"
31 
32 static const struct pci_device_id ish_pci_tbl[] = {
33 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, CHV_DEVICE_ID)},
34 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, BXT_Ax_DEVICE_ID)},
35 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, BXT_Bx_DEVICE_ID)},
36 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, APL_Ax_DEVICE_ID)},
37 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, SPT_Ax_DEVICE_ID)},
38 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, CNL_Ax_DEVICE_ID)},
39 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, GLK_Ax_DEVICE_ID)},
40 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, CNL_H_DEVICE_ID)},
41 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, SPT_H_DEVICE_ID)},
42 	{0, }
43 };
44 MODULE_DEVICE_TABLE(pci, ish_pci_tbl);
45 
46 /**
47  * ish_event_tracer() - Callback function to dump trace messages
48  * @dev:	ishtp device
49  * @format:	printf style format
50  *
51  * Callback to direct log messages to Linux trace buffers
52  */
53 static __printf(2, 3)
54 void ish_event_tracer(struct ishtp_device *dev, const char *format, ...)
55 {
56 	if (trace_ishtp_dump_enabled()) {
57 		va_list args;
58 		char tmp_buf[100];
59 
60 		va_start(args, format);
61 		vsnprintf(tmp_buf, sizeof(tmp_buf), format, args);
62 		va_end(args);
63 
64 		trace_ishtp_dump(tmp_buf);
65 	}
66 }
67 
68 /**
69  * ish_init() - Init function
70  * @dev:	ishtp device
71  *
72  * This function initialize wait queues for suspend/resume and call
73  * calls hadware initialization function. This will initiate
74  * startup sequence
75  *
76  * Return: 0 for success or error code for failure
77  */
78 static int ish_init(struct ishtp_device *dev)
79 {
80 	int ret;
81 
82 	/* Set the state of ISH HW to start */
83 	ret = ish_hw_start(dev);
84 	if (ret) {
85 		dev_err(dev->devc, "ISH: hw start failed.\n");
86 		return ret;
87 	}
88 
89 	/* Start the inter process communication to ISH processor */
90 	ret = ishtp_start(dev);
91 	if (ret) {
92 		dev_err(dev->devc, "ISHTP: Protocol init failed.\n");
93 		return ret;
94 	}
95 
96 	return 0;
97 }
98 
99 static const struct pci_device_id ish_invalid_pci_ids[] = {
100 	/* Mehlow platform special pci ids */
101 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0xA309)},
102 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0xA30A)},
103 	{}
104 };
105 
106 /**
107  * ish_probe() - PCI driver probe callback
108  * @pdev:	pci device
109  * @ent:	pci device id
110  *
111  * Initialize PCI function, setup interrupt and call for ISH initialization
112  *
113  * Return: 0 for success or error code for failure
114  */
115 static int ish_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
116 {
117 	struct ishtp_device *dev;
118 	struct ish_hw *hw;
119 	int	ret;
120 
121 	/* Check for invalid platforms for ISH support */
122 	if (pci_dev_present(ish_invalid_pci_ids))
123 		return -ENODEV;
124 
125 	/* enable pci dev */
126 	ret = pci_enable_device(pdev);
127 	if (ret) {
128 		dev_err(&pdev->dev, "ISH: Failed to enable PCI device\n");
129 		return ret;
130 	}
131 
132 	/* set PCI host mastering */
133 	pci_set_master(pdev);
134 
135 	/* pci request regions for ISH driver */
136 	ret = pci_request_regions(pdev, KBUILD_MODNAME);
137 	if (ret) {
138 		dev_err(&pdev->dev, "ISH: Failed to get PCI regions\n");
139 		goto disable_device;
140 	}
141 
142 	/* allocates and initializes the ISH dev structure */
143 	dev = ish_dev_init(pdev);
144 	if (!dev) {
145 		ret = -ENOMEM;
146 		goto release_regions;
147 	}
148 	hw = to_ish_hw(dev);
149 	dev->print_log = ish_event_tracer;
150 
151 	/* mapping IO device memory */
152 	hw->mem_addr = pci_iomap(pdev, 0, 0);
153 	if (!hw->mem_addr) {
154 		dev_err(&pdev->dev, "ISH: mapping I/O range failure\n");
155 		ret = -ENOMEM;
156 		goto free_device;
157 	}
158 
159 	dev->pdev = pdev;
160 
161 	pdev->dev_flags |= PCI_DEV_FLAGS_NO_D3;
162 
163 	/* request and enable interrupt */
164 	ret = request_irq(pdev->irq, ish_irq_handler, IRQF_SHARED,
165 			  KBUILD_MODNAME, dev);
166 	if (ret) {
167 		dev_err(&pdev->dev, "ISH: request IRQ failure (%d)\n",
168 			pdev->irq);
169 		goto free_device;
170 	}
171 
172 	dev_set_drvdata(dev->devc, dev);
173 
174 	init_waitqueue_head(&dev->suspend_wait);
175 	init_waitqueue_head(&dev->resume_wait);
176 
177 	ret = ish_init(dev);
178 	if (ret)
179 		goto free_irq;
180 
181 	return 0;
182 
183 free_irq:
184 	free_irq(pdev->irq, dev);
185 free_device:
186 	pci_iounmap(pdev, hw->mem_addr);
187 release_regions:
188 	pci_release_regions(pdev);
189 disable_device:
190 	pci_clear_master(pdev);
191 	pci_disable_device(pdev);
192 	dev_err(&pdev->dev, "ISH: PCI driver initialization failed.\n");
193 
194 	return ret;
195 }
196 
197 /**
198  * ish_remove() - PCI driver remove callback
199  * @pdev:	pci device
200  *
201  * This function does cleanup of ISH on pci remove callback
202  */
203 static void ish_remove(struct pci_dev *pdev)
204 {
205 	struct ishtp_device *ishtp_dev = pci_get_drvdata(pdev);
206 	struct ish_hw *hw = to_ish_hw(ishtp_dev);
207 
208 	ishtp_bus_remove_all_clients(ishtp_dev, false);
209 	ish_device_disable(ishtp_dev);
210 
211 	free_irq(pdev->irq, ishtp_dev);
212 	pci_iounmap(pdev, hw->mem_addr);
213 	pci_release_regions(pdev);
214 	pci_clear_master(pdev);
215 	pci_disable_device(pdev);
216 }
217 
218 static struct device __maybe_unused *ish_resume_device;
219 
220 /* 50ms to get resume response */
221 #define WAIT_FOR_RESUME_ACK_MS		50
222 
223 /**
224  * ish_resume_handler() - Work function to complete resume
225  * @work:	work struct
226  *
227  * The resume work function to complete resume function asynchronously.
228  * There are two resume paths, one where ISH is not powered off,
229  * in that case a simple resume message is enough, others we need
230  * a reset sequence.
231  */
232 static void __maybe_unused ish_resume_handler(struct work_struct *work)
233 {
234 	struct pci_dev *pdev = to_pci_dev(ish_resume_device);
235 	struct ishtp_device *dev = pci_get_drvdata(pdev);
236 	uint32_t fwsts;
237 	int ret;
238 
239 	/* Get ISH FW status */
240 	fwsts = IPC_GET_ISH_FWSTS(dev->ops->get_fw_status(dev));
241 
242 	/*
243 	 * If currently, in ISH FW, sensor app is loaded or beyond that,
244 	 * it means ISH isn't powered off, in this case, send a resume message.
245 	 */
246 	if (fwsts >= FWSTS_SENSOR_APP_LOADED) {
247 		ishtp_send_resume(dev);
248 
249 		/* Waiting to get resume response */
250 		if (dev->resume_flag)
251 			ret = wait_event_interruptible_timeout(dev->resume_wait,
252 				!dev->resume_flag,
253 				msecs_to_jiffies(WAIT_FOR_RESUME_ACK_MS));
254 	}
255 
256 	/*
257 	 * If in ISH FW, sensor app isn't loaded yet, or no resume response.
258 	 * That means this platform is not S0ix compatible, or something is
259 	 * wrong with ISH FW. So on resume, full reboot of ISH processor will
260 	 * happen, so need to go through init sequence again.
261 	 */
262 	if (dev->resume_flag)
263 		ish_init(dev);
264 }
265 
266 /**
267  * ish_suspend() - ISH suspend callback
268  * @device:	device pointer
269  *
270  * ISH suspend callback
271  *
272  * Return: 0 to the pm core
273  */
274 static int __maybe_unused ish_suspend(struct device *device)
275 {
276 	struct pci_dev *pdev = to_pci_dev(device);
277 	struct ishtp_device *dev = pci_get_drvdata(pdev);
278 
279 	enable_irq_wake(pdev->irq);
280 	/*
281 	 * If previous suspend hasn't been asnwered then ISH is likely dead,
282 	 * don't attempt nested notification
283 	 */
284 	if (dev->suspend_flag)
285 		return	0;
286 
287 	dev->resume_flag = 0;
288 	dev->suspend_flag = 1;
289 	ishtp_send_suspend(dev);
290 
291 	/* 25 ms should be enough for live ISH to flush all IPC buf */
292 	if (dev->suspend_flag)
293 		wait_event_interruptible_timeout(dev->suspend_wait,
294 						 !dev->suspend_flag,
295 						  msecs_to_jiffies(25));
296 
297 	return 0;
298 }
299 
300 static __maybe_unused DECLARE_WORK(resume_work, ish_resume_handler);
301 /**
302  * ish_resume() - ISH resume callback
303  * @device:	device pointer
304  *
305  * ISH resume callback
306  *
307  * Return: 0 to the pm core
308  */
309 static int __maybe_unused ish_resume(struct device *device)
310 {
311 	struct pci_dev *pdev = to_pci_dev(device);
312 	struct ishtp_device *dev = pci_get_drvdata(pdev);
313 
314 	ish_resume_device = device;
315 	dev->resume_flag = 1;
316 
317 	disable_irq_wake(pdev->irq);
318 	schedule_work(&resume_work);
319 
320 	return 0;
321 }
322 
323 static SIMPLE_DEV_PM_OPS(ish_pm_ops, ish_suspend, ish_resume);
324 
325 static struct pci_driver ish_driver = {
326 	.name = KBUILD_MODNAME,
327 	.id_table = ish_pci_tbl,
328 	.probe = ish_probe,
329 	.remove = ish_remove,
330 	.driver.pm = &ish_pm_ops,
331 };
332 
333 module_pci_driver(ish_driver);
334 
335 /* Original author */
336 MODULE_AUTHOR("Daniel Drubin <daniel.drubin@intel.com>");
337 /* Adoption to upstream Linux kernel */
338 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
339 
340 MODULE_DESCRIPTION("Intel(R) Integrated Sensor Hub PCI Device Driver");
341 MODULE_LICENSE("GPL");
342