xref: /openbmc/linux/drivers/memory/mtk-smi.c (revision 6cd70754)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2015-2016 MediaTek Inc.
4  * Author: Yong Wu <yong.wu@mediatek.com>
5  */
6 #include <linux/clk.h>
7 #include <linux/component.h>
8 #include <linux/device.h>
9 #include <linux/err.h>
10 #include <linux/io.h>
11 #include <linux/module.h>
12 #include <linux/of.h>
13 #include <linux/of_platform.h>
14 #include <linux/platform_device.h>
15 #include <linux/pm_runtime.h>
16 #include <soc/mediatek/smi.h>
17 #include <dt-bindings/memory/mt2701-larb-port.h>
18 #include <dt-bindings/memory/mtk-memory-port.h>
19 
20 /* mt8173 */
21 #define SMI_LARB_MMU_EN		0xf00
22 
23 /* mt8167 */
24 #define MT8167_SMI_LARB_MMU_EN	0xfc0
25 
26 /* mt2701 */
27 #define REG_SMI_SECUR_CON_BASE		0x5c0
28 
29 /* every register control 8 port, register offset 0x4 */
30 #define REG_SMI_SECUR_CON_OFFSET(id)	(((id) >> 3) << 2)
31 #define REG_SMI_SECUR_CON_ADDR(id)	\
32 	(REG_SMI_SECUR_CON_BASE + REG_SMI_SECUR_CON_OFFSET(id))
33 
34 /*
35  * every port have 4 bit to control, bit[port + 3] control virtual or physical,
36  * bit[port + 2 : port + 1] control the domain, bit[port] control the security
37  * or non-security.
38  */
39 #define SMI_SECUR_CON_VAL_MSK(id)	(~(0xf << (((id) & 0x7) << 2)))
40 #define SMI_SECUR_CON_VAL_VIRT(id)	BIT((((id) & 0x7) << 2) + 3)
41 /* mt2701 domain should be set to 3 */
42 #define SMI_SECUR_CON_VAL_DOMAIN(id)	(0x3 << ((((id) & 0x7) << 2) + 1))
43 
44 /* mt2712 */
45 #define SMI_LARB_NONSEC_CON(id)	(0x380 + ((id) * 4))
46 #define F_MMU_EN		BIT(0)
47 #define BANK_SEL(id)		({			\
48 	u32 _id = (id) & 0x3;				\
49 	(_id << 8 | _id << 10 | _id << 12 | _id << 14);	\
50 })
51 
52 /* SMI COMMON */
53 #define SMI_BUS_SEL			0x220
54 #define SMI_BUS_LARB_SHIFT(larbid)	((larbid) << 1)
55 /* All are MMU0 defaultly. Only specialize mmu1 here. */
56 #define F_MMU1_LARB(larbid)		(0x1 << SMI_BUS_LARB_SHIFT(larbid))
57 
58 enum mtk_smi_gen {
59 	MTK_SMI_GEN1,
60 	MTK_SMI_GEN2
61 };
62 
63 struct mtk_smi_common_plat {
64 	enum mtk_smi_gen gen;
65 	bool             has_gals;
66 	u32              bus_sel; /* Balance some larbs to enter mmu0 or mmu1 */
67 };
68 
69 struct mtk_smi_larb_gen {
70 	int port_in_larb[MTK_LARB_NR_MAX + 1];
71 	void (*config_port)(struct device *dev);
72 	unsigned int			larb_direct_to_common_mask;
73 	bool				has_gals;
74 };
75 
76 struct mtk_smi {
77 	struct device			*dev;
78 	struct clk			*clk_apb, *clk_smi;
79 	struct clk			*clk_gals0, *clk_gals1;
80 	struct clk			*clk_async; /*only needed by mt2701*/
81 	union {
82 		void __iomem		*smi_ao_base; /* only for gen1 */
83 		void __iomem		*base;	      /* only for gen2 */
84 	};
85 	const struct mtk_smi_common_plat *plat;
86 };
87 
88 struct mtk_smi_larb { /* larb: local arbiter */
89 	struct mtk_smi			smi;
90 	void __iomem			*base;
91 	struct device			*smi_common_dev;
92 	const struct mtk_smi_larb_gen	*larb_gen;
93 	int				larbid;
94 	u32				*mmu;
95 	unsigned char			*bank;
96 };
97 
98 static int mtk_smi_clk_enable(const struct mtk_smi *smi)
99 {
100 	int ret;
101 
102 	ret = clk_prepare_enable(smi->clk_apb);
103 	if (ret)
104 		return ret;
105 
106 	ret = clk_prepare_enable(smi->clk_smi);
107 	if (ret)
108 		goto err_disable_apb;
109 
110 	ret = clk_prepare_enable(smi->clk_gals0);
111 	if (ret)
112 		goto err_disable_smi;
113 
114 	ret = clk_prepare_enable(smi->clk_gals1);
115 	if (ret)
116 		goto err_disable_gals0;
117 
118 	return 0;
119 
120 err_disable_gals0:
121 	clk_disable_unprepare(smi->clk_gals0);
122 err_disable_smi:
123 	clk_disable_unprepare(smi->clk_smi);
124 err_disable_apb:
125 	clk_disable_unprepare(smi->clk_apb);
126 	return ret;
127 }
128 
129 static void mtk_smi_clk_disable(const struct mtk_smi *smi)
130 {
131 	clk_disable_unprepare(smi->clk_gals1);
132 	clk_disable_unprepare(smi->clk_gals0);
133 	clk_disable_unprepare(smi->clk_smi);
134 	clk_disable_unprepare(smi->clk_apb);
135 }
136 
137 int mtk_smi_larb_get(struct device *larbdev)
138 {
139 	int ret = pm_runtime_resume_and_get(larbdev);
140 
141 	return (ret < 0) ? ret : 0;
142 }
143 EXPORT_SYMBOL_GPL(mtk_smi_larb_get);
144 
145 void mtk_smi_larb_put(struct device *larbdev)
146 {
147 	pm_runtime_put_sync(larbdev);
148 }
149 EXPORT_SYMBOL_GPL(mtk_smi_larb_put);
150 
151 static int
152 mtk_smi_larb_bind(struct device *dev, struct device *master, void *data)
153 {
154 	struct mtk_smi_larb *larb = dev_get_drvdata(dev);
155 	struct mtk_smi_larb_iommu *larb_mmu = data;
156 	unsigned int         i;
157 
158 	for (i = 0; i < MTK_LARB_NR_MAX; i++) {
159 		if (dev == larb_mmu[i].dev) {
160 			larb->larbid = i;
161 			larb->mmu = &larb_mmu[i].mmu;
162 			larb->bank = larb_mmu[i].bank;
163 			return 0;
164 		}
165 	}
166 	return -ENODEV;
167 }
168 
169 static void mtk_smi_larb_config_port_gen2_general(struct device *dev)
170 {
171 	struct mtk_smi_larb *larb = dev_get_drvdata(dev);
172 	u32 reg;
173 	int i;
174 
175 	if (BIT(larb->larbid) & larb->larb_gen->larb_direct_to_common_mask)
176 		return;
177 
178 	for_each_set_bit(i, (unsigned long *)larb->mmu, 32) {
179 		reg = readl_relaxed(larb->base + SMI_LARB_NONSEC_CON(i));
180 		reg |= F_MMU_EN;
181 		reg |= BANK_SEL(larb->bank[i]);
182 		writel(reg, larb->base + SMI_LARB_NONSEC_CON(i));
183 	}
184 }
185 
186 static void mtk_smi_larb_config_port_mt8173(struct device *dev)
187 {
188 	struct mtk_smi_larb *larb = dev_get_drvdata(dev);
189 
190 	writel(*larb->mmu, larb->base + SMI_LARB_MMU_EN);
191 }
192 
193 static void mtk_smi_larb_config_port_mt8167(struct device *dev)
194 {
195 	struct mtk_smi_larb *larb = dev_get_drvdata(dev);
196 
197 	writel(*larb->mmu, larb->base + MT8167_SMI_LARB_MMU_EN);
198 }
199 
200 static void mtk_smi_larb_config_port_gen1(struct device *dev)
201 {
202 	struct mtk_smi_larb *larb = dev_get_drvdata(dev);
203 	const struct mtk_smi_larb_gen *larb_gen = larb->larb_gen;
204 	struct mtk_smi *common = dev_get_drvdata(larb->smi_common_dev);
205 	int i, m4u_port_id, larb_port_num;
206 	u32 sec_con_val, reg_val;
207 
208 	m4u_port_id = larb_gen->port_in_larb[larb->larbid];
209 	larb_port_num = larb_gen->port_in_larb[larb->larbid + 1]
210 			- larb_gen->port_in_larb[larb->larbid];
211 
212 	for (i = 0; i < larb_port_num; i++, m4u_port_id++) {
213 		if (*larb->mmu & BIT(i)) {
214 			/* bit[port + 3] controls the virtual or physical */
215 			sec_con_val = SMI_SECUR_CON_VAL_VIRT(m4u_port_id);
216 		} else {
217 			/* do not need to enable m4u for this port */
218 			continue;
219 		}
220 		reg_val = readl(common->smi_ao_base
221 			+ REG_SMI_SECUR_CON_ADDR(m4u_port_id));
222 		reg_val &= SMI_SECUR_CON_VAL_MSK(m4u_port_id);
223 		reg_val |= sec_con_val;
224 		reg_val |= SMI_SECUR_CON_VAL_DOMAIN(m4u_port_id);
225 		writel(reg_val,
226 			common->smi_ao_base
227 			+ REG_SMI_SECUR_CON_ADDR(m4u_port_id));
228 	}
229 }
230 
231 static void
232 mtk_smi_larb_unbind(struct device *dev, struct device *master, void *data)
233 {
234 	/* Do nothing as the iommu is always enabled. */
235 }
236 
237 static const struct component_ops mtk_smi_larb_component_ops = {
238 	.bind = mtk_smi_larb_bind,
239 	.unbind = mtk_smi_larb_unbind,
240 };
241 
242 static const struct mtk_smi_larb_gen mtk_smi_larb_mt8173 = {
243 	/* mt8173 do not need the port in larb */
244 	.config_port = mtk_smi_larb_config_port_mt8173,
245 };
246 
247 static const struct mtk_smi_larb_gen mtk_smi_larb_mt8167 = {
248 	/* mt8167 do not need the port in larb */
249 	.config_port = mtk_smi_larb_config_port_mt8167,
250 };
251 
252 static const struct mtk_smi_larb_gen mtk_smi_larb_mt2701 = {
253 	.port_in_larb = {
254 		LARB0_PORT_OFFSET, LARB1_PORT_OFFSET,
255 		LARB2_PORT_OFFSET, LARB3_PORT_OFFSET
256 	},
257 	.config_port = mtk_smi_larb_config_port_gen1,
258 };
259 
260 static const struct mtk_smi_larb_gen mtk_smi_larb_mt2712 = {
261 	.config_port                = mtk_smi_larb_config_port_gen2_general,
262 	.larb_direct_to_common_mask = BIT(8) | BIT(9),      /* bdpsys */
263 };
264 
265 static const struct mtk_smi_larb_gen mtk_smi_larb_mt6779 = {
266 	.config_port  = mtk_smi_larb_config_port_gen2_general,
267 	.larb_direct_to_common_mask =
268 		BIT(4) | BIT(6) | BIT(11) | BIT(12) | BIT(13),
269 		/* DUMMY | IPU0 | IPU1 | CCU | MDLA */
270 };
271 
272 static const struct mtk_smi_larb_gen mtk_smi_larb_mt8183 = {
273 	.has_gals                   = true,
274 	.config_port                = mtk_smi_larb_config_port_gen2_general,
275 	.larb_direct_to_common_mask = BIT(2) | BIT(3) | BIT(7),
276 				      /* IPU0 | IPU1 | CCU */
277 };
278 
279 static const struct mtk_smi_larb_gen mtk_smi_larb_mt8192 = {
280 	.config_port                = mtk_smi_larb_config_port_gen2_general,
281 };
282 
283 static const struct of_device_id mtk_smi_larb_of_ids[] = {
284 	{
285 		.compatible = "mediatek,mt8167-smi-larb",
286 		.data = &mtk_smi_larb_mt8167
287 	},
288 	{
289 		.compatible = "mediatek,mt8173-smi-larb",
290 		.data = &mtk_smi_larb_mt8173
291 	},
292 	{
293 		.compatible = "mediatek,mt2701-smi-larb",
294 		.data = &mtk_smi_larb_mt2701
295 	},
296 	{
297 		.compatible = "mediatek,mt2712-smi-larb",
298 		.data = &mtk_smi_larb_mt2712
299 	},
300 	{
301 		.compatible = "mediatek,mt6779-smi-larb",
302 		.data = &mtk_smi_larb_mt6779
303 	},
304 	{
305 		.compatible = "mediatek,mt8183-smi-larb",
306 		.data = &mtk_smi_larb_mt8183
307 	},
308 	{
309 		.compatible = "mediatek,mt8192-smi-larb",
310 		.data = &mtk_smi_larb_mt8192
311 	},
312 	{}
313 };
314 
315 static int mtk_smi_larb_probe(struct platform_device *pdev)
316 {
317 	struct mtk_smi_larb *larb;
318 	struct resource *res;
319 	struct device *dev = &pdev->dev;
320 	struct device_node *smi_node;
321 	struct platform_device *smi_pdev;
322 
323 	larb = devm_kzalloc(dev, sizeof(*larb), GFP_KERNEL);
324 	if (!larb)
325 		return -ENOMEM;
326 
327 	larb->larb_gen = of_device_get_match_data(dev);
328 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
329 	larb->base = devm_ioremap_resource(dev, res);
330 	if (IS_ERR(larb->base))
331 		return PTR_ERR(larb->base);
332 
333 	larb->smi.clk_apb = devm_clk_get(dev, "apb");
334 	if (IS_ERR(larb->smi.clk_apb))
335 		return PTR_ERR(larb->smi.clk_apb);
336 
337 	larb->smi.clk_smi = devm_clk_get(dev, "smi");
338 	if (IS_ERR(larb->smi.clk_smi))
339 		return PTR_ERR(larb->smi.clk_smi);
340 
341 	if (larb->larb_gen->has_gals) {
342 		/* The larbs may still haven't gals even if the SoC support.*/
343 		larb->smi.clk_gals0 = devm_clk_get(dev, "gals");
344 		if (PTR_ERR(larb->smi.clk_gals0) == -ENOENT)
345 			larb->smi.clk_gals0 = NULL;
346 		else if (IS_ERR(larb->smi.clk_gals0))
347 			return PTR_ERR(larb->smi.clk_gals0);
348 	}
349 	larb->smi.dev = dev;
350 
351 	smi_node = of_parse_phandle(dev->of_node, "mediatek,smi", 0);
352 	if (!smi_node)
353 		return -EINVAL;
354 
355 	smi_pdev = of_find_device_by_node(smi_node);
356 	of_node_put(smi_node);
357 	if (smi_pdev) {
358 		if (!platform_get_drvdata(smi_pdev))
359 			return -EPROBE_DEFER;
360 		larb->smi_common_dev = &smi_pdev->dev;
361 	} else {
362 		dev_err(dev, "Failed to get the smi_common device\n");
363 		return -EINVAL;
364 	}
365 
366 	pm_runtime_enable(dev);
367 	platform_set_drvdata(pdev, larb);
368 	return component_add(dev, &mtk_smi_larb_component_ops);
369 }
370 
371 static int mtk_smi_larb_remove(struct platform_device *pdev)
372 {
373 	pm_runtime_disable(&pdev->dev);
374 	component_del(&pdev->dev, &mtk_smi_larb_component_ops);
375 	return 0;
376 }
377 
378 static int __maybe_unused mtk_smi_larb_resume(struct device *dev)
379 {
380 	struct mtk_smi_larb *larb = dev_get_drvdata(dev);
381 	const struct mtk_smi_larb_gen *larb_gen = larb->larb_gen;
382 	int ret;
383 
384 	/* Power on smi-common. */
385 	ret = pm_runtime_resume_and_get(larb->smi_common_dev);
386 	if (ret < 0) {
387 		dev_err(dev, "Failed to pm get for smi-common(%d).\n", ret);
388 		return ret;
389 	}
390 
391 	ret = mtk_smi_clk_enable(&larb->smi);
392 	if (ret < 0) {
393 		dev_err(dev, "Failed to enable clock(%d).\n", ret);
394 		pm_runtime_put_sync(larb->smi_common_dev);
395 		return ret;
396 	}
397 
398 	/* Configure the basic setting for this larb */
399 	larb_gen->config_port(dev);
400 
401 	return 0;
402 }
403 
404 static int __maybe_unused mtk_smi_larb_suspend(struct device *dev)
405 {
406 	struct mtk_smi_larb *larb = dev_get_drvdata(dev);
407 
408 	mtk_smi_clk_disable(&larb->smi);
409 	pm_runtime_put_sync(larb->smi_common_dev);
410 	return 0;
411 }
412 
413 static const struct dev_pm_ops smi_larb_pm_ops = {
414 	SET_RUNTIME_PM_OPS(mtk_smi_larb_suspend, mtk_smi_larb_resume, NULL)
415 	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
416 				     pm_runtime_force_resume)
417 };
418 
419 static struct platform_driver mtk_smi_larb_driver = {
420 	.probe	= mtk_smi_larb_probe,
421 	.remove	= mtk_smi_larb_remove,
422 	.driver	= {
423 		.name = "mtk-smi-larb",
424 		.of_match_table = mtk_smi_larb_of_ids,
425 		.pm             = &smi_larb_pm_ops,
426 	}
427 };
428 
429 static const struct mtk_smi_common_plat mtk_smi_common_gen1 = {
430 	.gen = MTK_SMI_GEN1,
431 };
432 
433 static const struct mtk_smi_common_plat mtk_smi_common_gen2 = {
434 	.gen = MTK_SMI_GEN2,
435 };
436 
437 static const struct mtk_smi_common_plat mtk_smi_common_mt6779 = {
438 	.gen		= MTK_SMI_GEN2,
439 	.has_gals	= true,
440 	.bus_sel	= F_MMU1_LARB(1) | F_MMU1_LARB(2) | F_MMU1_LARB(4) |
441 			  F_MMU1_LARB(5) | F_MMU1_LARB(6) | F_MMU1_LARB(7),
442 };
443 
444 static const struct mtk_smi_common_plat mtk_smi_common_mt8183 = {
445 	.gen      = MTK_SMI_GEN2,
446 	.has_gals = true,
447 	.bus_sel  = F_MMU1_LARB(1) | F_MMU1_LARB(2) | F_MMU1_LARB(5) |
448 		    F_MMU1_LARB(7),
449 };
450 
451 static const struct mtk_smi_common_plat mtk_smi_common_mt8192 = {
452 	.gen      = MTK_SMI_GEN2,
453 	.has_gals = true,
454 	.bus_sel  = F_MMU1_LARB(1) | F_MMU1_LARB(2) | F_MMU1_LARB(5) |
455 		    F_MMU1_LARB(6),
456 };
457 
458 static const struct of_device_id mtk_smi_common_of_ids[] = {
459 	{
460 		.compatible = "mediatek,mt8173-smi-common",
461 		.data = &mtk_smi_common_gen2,
462 	},
463 	{
464 		.compatible = "mediatek,mt8167-smi-common",
465 		.data = &mtk_smi_common_gen2,
466 	},
467 	{
468 		.compatible = "mediatek,mt2701-smi-common",
469 		.data = &mtk_smi_common_gen1,
470 	},
471 	{
472 		.compatible = "mediatek,mt2712-smi-common",
473 		.data = &mtk_smi_common_gen2,
474 	},
475 	{
476 		.compatible = "mediatek,mt6779-smi-common",
477 		.data = &mtk_smi_common_mt6779,
478 	},
479 	{
480 		.compatible = "mediatek,mt8183-smi-common",
481 		.data = &mtk_smi_common_mt8183,
482 	},
483 	{
484 		.compatible = "mediatek,mt8192-smi-common",
485 		.data = &mtk_smi_common_mt8192,
486 	},
487 	{}
488 };
489 
490 static int mtk_smi_common_probe(struct platform_device *pdev)
491 {
492 	struct device *dev = &pdev->dev;
493 	struct mtk_smi *common;
494 	struct resource *res;
495 	int ret;
496 
497 	common = devm_kzalloc(dev, sizeof(*common), GFP_KERNEL);
498 	if (!common)
499 		return -ENOMEM;
500 	common->dev = dev;
501 	common->plat = of_device_get_match_data(dev);
502 
503 	common->clk_apb = devm_clk_get(dev, "apb");
504 	if (IS_ERR(common->clk_apb))
505 		return PTR_ERR(common->clk_apb);
506 
507 	common->clk_smi = devm_clk_get(dev, "smi");
508 	if (IS_ERR(common->clk_smi))
509 		return PTR_ERR(common->clk_smi);
510 
511 	if (common->plat->has_gals) {
512 		common->clk_gals0 = devm_clk_get(dev, "gals0");
513 		if (IS_ERR(common->clk_gals0))
514 			return PTR_ERR(common->clk_gals0);
515 
516 		common->clk_gals1 = devm_clk_get(dev, "gals1");
517 		if (IS_ERR(common->clk_gals1))
518 			return PTR_ERR(common->clk_gals1);
519 	}
520 
521 	/*
522 	 * for mtk smi gen 1, we need to get the ao(always on) base to config
523 	 * m4u port, and we need to enable the aync clock for transform the smi
524 	 * clock into emi clock domain, but for mtk smi gen2, there's no smi ao
525 	 * base.
526 	 */
527 	if (common->plat->gen == MTK_SMI_GEN1) {
528 		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
529 		common->smi_ao_base = devm_ioremap_resource(dev, res);
530 		if (IS_ERR(common->smi_ao_base))
531 			return PTR_ERR(common->smi_ao_base);
532 
533 		common->clk_async = devm_clk_get(dev, "async");
534 		if (IS_ERR(common->clk_async))
535 			return PTR_ERR(common->clk_async);
536 
537 		ret = clk_prepare_enable(common->clk_async);
538 		if (ret)
539 			return ret;
540 	} else {
541 		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
542 		common->base = devm_ioremap_resource(dev, res);
543 		if (IS_ERR(common->base))
544 			return PTR_ERR(common->base);
545 	}
546 	pm_runtime_enable(dev);
547 	platform_set_drvdata(pdev, common);
548 	return 0;
549 }
550 
551 static int mtk_smi_common_remove(struct platform_device *pdev)
552 {
553 	pm_runtime_disable(&pdev->dev);
554 	return 0;
555 }
556 
557 static int __maybe_unused mtk_smi_common_resume(struct device *dev)
558 {
559 	struct mtk_smi *common = dev_get_drvdata(dev);
560 	u32 bus_sel = common->plat->bus_sel;
561 	int ret;
562 
563 	ret = mtk_smi_clk_enable(common);
564 	if (ret) {
565 		dev_err(common->dev, "Failed to enable clock(%d).\n", ret);
566 		return ret;
567 	}
568 
569 	if (common->plat->gen == MTK_SMI_GEN2 && bus_sel)
570 		writel(bus_sel, common->base + SMI_BUS_SEL);
571 	return 0;
572 }
573 
574 static int __maybe_unused mtk_smi_common_suspend(struct device *dev)
575 {
576 	struct mtk_smi *common = dev_get_drvdata(dev);
577 
578 	mtk_smi_clk_disable(common);
579 	return 0;
580 }
581 
582 static const struct dev_pm_ops smi_common_pm_ops = {
583 	SET_RUNTIME_PM_OPS(mtk_smi_common_suspend, mtk_smi_common_resume, NULL)
584 	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
585 				     pm_runtime_force_resume)
586 };
587 
588 static struct platform_driver mtk_smi_common_driver = {
589 	.probe	= mtk_smi_common_probe,
590 	.remove = mtk_smi_common_remove,
591 	.driver	= {
592 		.name = "mtk-smi-common",
593 		.of_match_table = mtk_smi_common_of_ids,
594 		.pm             = &smi_common_pm_ops,
595 	}
596 };
597 
598 static struct platform_driver * const smidrivers[] = {
599 	&mtk_smi_common_driver,
600 	&mtk_smi_larb_driver,
601 };
602 
603 static int __init mtk_smi_init(void)
604 {
605 	return platform_register_drivers(smidrivers, ARRAY_SIZE(smidrivers));
606 }
607 module_init(mtk_smi_init);
608 
609 static void __exit mtk_smi_exit(void)
610 {
611 	platform_unregister_drivers(smidrivers, ARRAY_SIZE(smidrivers));
612 }
613 module_exit(mtk_smi_exit);
614 
615 MODULE_DESCRIPTION("MediaTek SMI driver");
616 MODULE_LICENSE("GPL v2");
617