xref: /linux/drivers/misc/cb710/core.c (revision 37744feebc086908fd89760650f458ab19071750)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  cb710/core.c
4  *
5  *  Copyright by Michał Mirosław, 2008-2009
6  */
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/pci.h>
10 #include <linux/spinlock.h>
11 #include <linux/idr.h>
12 #include <linux/cb710.h>
13 #include <linux/gfp.h>
14 
15 static DEFINE_IDA(cb710_ida);
16 
17 void cb710_pci_update_config_reg(struct pci_dev *pdev,
18 	int reg, uint32_t mask, uint32_t xor)
19 {
20 	u32 rval;
21 
22 	pci_read_config_dword(pdev, reg, &rval);
23 	rval = (rval & mask) ^ xor;
24 	pci_write_config_dword(pdev, reg, rval);
25 }
26 EXPORT_SYMBOL_GPL(cb710_pci_update_config_reg);
27 
28 /* Some magic writes based on Windows driver init code */
29 static int cb710_pci_configure(struct pci_dev *pdev)
30 {
31 	unsigned int devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
32 	struct pci_dev *pdev0;
33 	u32 val;
34 
35 	cb710_pci_update_config_reg(pdev, 0x48,
36 		~0x000000FF, 0x0000003F);
37 
38 	pci_read_config_dword(pdev, 0x48, &val);
39 	if (val & 0x80000000)
40 		return 0;
41 
42 	pdev0 = pci_get_slot(pdev->bus, devfn);
43 	if (!pdev0)
44 		return -ENODEV;
45 
46 	if (pdev0->vendor == PCI_VENDOR_ID_ENE
47 	    && pdev0->device == PCI_DEVICE_ID_ENE_720) {
48 		cb710_pci_update_config_reg(pdev0, 0x8C,
49 			~0x00F00000, 0x00100000);
50 		cb710_pci_update_config_reg(pdev0, 0xB0,
51 			~0x08000000, 0x08000000);
52 	}
53 
54 	cb710_pci_update_config_reg(pdev0, 0x8C,
55 		~0x00000F00, 0x00000200);
56 	cb710_pci_update_config_reg(pdev0, 0x90,
57 		~0x00060000, 0x00040000);
58 
59 	pci_dev_put(pdev0);
60 
61 	return 0;
62 }
63 
64 static irqreturn_t cb710_irq_handler(int irq, void *data)
65 {
66 	struct cb710_chip *chip = data;
67 	struct cb710_slot *slot = &chip->slot[0];
68 	irqreturn_t handled = IRQ_NONE;
69 	unsigned nr;
70 
71 	spin_lock(&chip->irq_lock); /* incl. smp_rmb() */
72 
73 	for (nr = chip->slots; nr; ++slot, --nr) {
74 		cb710_irq_handler_t handler_func = slot->irq_handler;
75 		if (handler_func && handler_func(slot))
76 			handled = IRQ_HANDLED;
77 	}
78 
79 	spin_unlock(&chip->irq_lock);
80 
81 	return handled;
82 }
83 
84 static void cb710_release_slot(struct device *dev)
85 {
86 #ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
87 	struct cb710_slot *slot = cb710_pdev_to_slot(to_platform_device(dev));
88 	struct cb710_chip *chip = cb710_slot_to_chip(slot);
89 
90 	/* slot struct can be freed now */
91 	atomic_dec(&chip->slot_refs_count);
92 #endif
93 }
94 
95 static int cb710_register_slot(struct cb710_chip *chip,
96 	unsigned slot_mask, unsigned io_offset, const char *name)
97 {
98 	int nr = chip->slots;
99 	struct cb710_slot *slot = &chip->slot[nr];
100 	int err;
101 
102 	dev_dbg(cb710_chip_dev(chip),
103 		"register: %s.%d; slot %d; mask %d; IO offset: 0x%02X\n",
104 		name, chip->platform_id, nr, slot_mask, io_offset);
105 
106 	/* slot->irq_handler == NULL here; this needs to be
107 	 * seen before platform_device_register() */
108 	++chip->slots;
109 	smp_wmb();
110 
111 	slot->iobase = chip->iobase + io_offset;
112 	slot->pdev.name = name;
113 	slot->pdev.id = chip->platform_id;
114 	slot->pdev.dev.parent = &chip->pdev->dev;
115 	slot->pdev.dev.release = cb710_release_slot;
116 
117 	err = platform_device_register(&slot->pdev);
118 
119 #ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
120 	atomic_inc(&chip->slot_refs_count);
121 #endif
122 
123 	if (err) {
124 		/* device_initialize() called from platform_device_register()
125 		 * wants this on error path */
126 		platform_device_put(&slot->pdev);
127 
128 		/* slot->irq_handler == NULL here anyway, so no lock needed */
129 		--chip->slots;
130 		return err;
131 	}
132 
133 	chip->slot_mask |= slot_mask;
134 
135 	return 0;
136 }
137 
138 static void cb710_unregister_slot(struct cb710_chip *chip,
139 	unsigned slot_mask)
140 {
141 	int nr = chip->slots - 1;
142 
143 	if (!(chip->slot_mask & slot_mask))
144 		return;
145 
146 	platform_device_unregister(&chip->slot[nr].pdev);
147 
148 	/* complementary to spin_unlock() in cb710_set_irq_handler() */
149 	smp_rmb();
150 	BUG_ON(chip->slot[nr].irq_handler != NULL);
151 
152 	/* slot->irq_handler == NULL here, so no lock needed */
153 	--chip->slots;
154 	chip->slot_mask &= ~slot_mask;
155 }
156 
157 void cb710_set_irq_handler(struct cb710_slot *slot,
158 	cb710_irq_handler_t handler)
159 {
160 	struct cb710_chip *chip = cb710_slot_to_chip(slot);
161 	unsigned long flags;
162 
163 	spin_lock_irqsave(&chip->irq_lock, flags);
164 	slot->irq_handler = handler;
165 	spin_unlock_irqrestore(&chip->irq_lock, flags);
166 }
167 EXPORT_SYMBOL_GPL(cb710_set_irq_handler);
168 
169 #ifdef CONFIG_PM
170 
171 static int cb710_suspend(struct pci_dev *pdev, pm_message_t state)
172 {
173 	struct cb710_chip *chip = pci_get_drvdata(pdev);
174 
175 	devm_free_irq(&pdev->dev, pdev->irq, chip);
176 	pci_save_state(pdev);
177 	pci_disable_device(pdev);
178 	if (state.event & PM_EVENT_SLEEP)
179 		pci_set_power_state(pdev, PCI_D3hot);
180 	return 0;
181 }
182 
183 static int cb710_resume(struct pci_dev *pdev)
184 {
185 	struct cb710_chip *chip = pci_get_drvdata(pdev);
186 	int err;
187 
188 	pci_set_power_state(pdev, PCI_D0);
189 	pci_restore_state(pdev);
190 	err = pcim_enable_device(pdev);
191 	if (err)
192 		return err;
193 
194 	return devm_request_irq(&pdev->dev, pdev->irq,
195 		cb710_irq_handler, IRQF_SHARED, KBUILD_MODNAME, chip);
196 }
197 
198 #endif /* CONFIG_PM */
199 
200 static int cb710_probe(struct pci_dev *pdev,
201 	const struct pci_device_id *ent)
202 {
203 	struct cb710_chip *chip;
204 	u32 val;
205 	int err;
206 	int n = 0;
207 
208 	err = cb710_pci_configure(pdev);
209 	if (err)
210 		return err;
211 
212 	/* this is actually magic... */
213 	pci_read_config_dword(pdev, 0x48, &val);
214 	if (!(val & 0x80000000)) {
215 		pci_write_config_dword(pdev, 0x48, val|0x71000000);
216 		pci_read_config_dword(pdev, 0x48, &val);
217 	}
218 
219 	dev_dbg(&pdev->dev, "PCI config[0x48] = 0x%08X\n", val);
220 	if (!(val & 0x70000000))
221 		return -ENODEV;
222 	val = (val >> 28) & 7;
223 	if (val & CB710_SLOT_MMC)
224 		++n;
225 	if (val & CB710_SLOT_MS)
226 		++n;
227 	if (val & CB710_SLOT_SM)
228 		++n;
229 
230 	chip = devm_kzalloc(&pdev->dev, struct_size(chip, slot, n),
231 			    GFP_KERNEL);
232 	if (!chip)
233 		return -ENOMEM;
234 
235 	err = pcim_enable_device(pdev);
236 	if (err)
237 		return err;
238 
239 	err = pcim_iomap_regions(pdev, 0x0001, KBUILD_MODNAME);
240 	if (err)
241 		return err;
242 
243 	spin_lock_init(&chip->irq_lock);
244 	chip->pdev = pdev;
245 	chip->iobase = pcim_iomap_table(pdev)[0];
246 
247 	pci_set_drvdata(pdev, chip);
248 
249 	err = devm_request_irq(&pdev->dev, pdev->irq,
250 		cb710_irq_handler, IRQF_SHARED, KBUILD_MODNAME, chip);
251 	if (err)
252 		return err;
253 
254 	err = ida_alloc(&cb710_ida, GFP_KERNEL);
255 	if (err < 0)
256 		return err;
257 	chip->platform_id = err;
258 
259 	dev_info(&pdev->dev, "id %d, IO 0x%p, IRQ %d\n",
260 		chip->platform_id, chip->iobase, pdev->irq);
261 
262 	if (val & CB710_SLOT_MMC) {	/* MMC/SD slot */
263 		err = cb710_register_slot(chip,
264 			CB710_SLOT_MMC, 0x00, "cb710-mmc");
265 		if (err)
266 			return err;
267 	}
268 
269 	if (val & CB710_SLOT_MS) {	/* MemoryStick slot */
270 		err = cb710_register_slot(chip,
271 			CB710_SLOT_MS, 0x40, "cb710-ms");
272 		if (err)
273 			goto unreg_mmc;
274 	}
275 
276 	if (val & CB710_SLOT_SM) {	/* SmartMedia slot */
277 		err = cb710_register_slot(chip,
278 			CB710_SLOT_SM, 0x60, "cb710-sm");
279 		if (err)
280 			goto unreg_ms;
281 	}
282 
283 	return 0;
284 unreg_ms:
285 	cb710_unregister_slot(chip, CB710_SLOT_MS);
286 unreg_mmc:
287 	cb710_unregister_slot(chip, CB710_SLOT_MMC);
288 
289 #ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
290 	BUG_ON(atomic_read(&chip->slot_refs_count) != 0);
291 #endif
292 	return err;
293 }
294 
295 static void cb710_remove_one(struct pci_dev *pdev)
296 {
297 	struct cb710_chip *chip = pci_get_drvdata(pdev);
298 
299 	cb710_unregister_slot(chip, CB710_SLOT_SM);
300 	cb710_unregister_slot(chip, CB710_SLOT_MS);
301 	cb710_unregister_slot(chip, CB710_SLOT_MMC);
302 #ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
303 	BUG_ON(atomic_read(&chip->slot_refs_count) != 0);
304 #endif
305 
306 	ida_free(&cb710_ida, chip->platform_id);
307 }
308 
309 static const struct pci_device_id cb710_pci_tbl[] = {
310 	{ PCI_VENDOR_ID_ENE, PCI_DEVICE_ID_ENE_CB710_FLASH,
311 		PCI_ANY_ID, PCI_ANY_ID, },
312 	{ 0, }
313 };
314 
315 static struct pci_driver cb710_driver = {
316 	.name = KBUILD_MODNAME,
317 	.id_table = cb710_pci_tbl,
318 	.probe = cb710_probe,
319 	.remove = cb710_remove_one,
320 #ifdef CONFIG_PM
321 	.suspend = cb710_suspend,
322 	.resume = cb710_resume,
323 #endif
324 };
325 
326 static int __init cb710_init_module(void)
327 {
328 	return pci_register_driver(&cb710_driver);
329 }
330 
331 static void __exit cb710_cleanup_module(void)
332 {
333 	pci_unregister_driver(&cb710_driver);
334 	ida_destroy(&cb710_ida);
335 }
336 
337 module_init(cb710_init_module);
338 module_exit(cb710_cleanup_module);
339 
340 MODULE_AUTHOR("Michał Mirosław <mirq-linux@rere.qmqm.pl>");
341 MODULE_DESCRIPTION("ENE CB710 memory card reader driver");
342 MODULE_LICENSE("GPL");
343 MODULE_DEVICE_TABLE(pci, cb710_pci_tbl);
344