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v6.8
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Emma Mobile Timer Support - STI
  4 *
  5 *  Copyright (C) 2012 Magnus Damm
 
 
 
 
 
 
 
 
 
 
 
 
 
  6 */
  7
  8#include <linux/init.h>
  9#include <linux/platform_device.h>
 10#include <linux/spinlock.h>
 11#include <linux/interrupt.h>
 12#include <linux/ioport.h>
 13#include <linux/io.h>
 14#include <linux/clk.h>
 15#include <linux/irq.h>
 16#include <linux/err.h>
 17#include <linux/delay.h>
 18#include <linux/clocksource.h>
 19#include <linux/clockchips.h>
 20#include <linux/slab.h>
 21#include <linux/module.h>
 22
 23enum { USER_CLOCKSOURCE, USER_CLOCKEVENT, USER_NR };
 24
 25struct em_sti_priv {
 26	void __iomem *base;
 27	struct clk *clk;
 28	struct platform_device *pdev;
 29	unsigned int active[USER_NR];
 30	unsigned long rate;
 31	raw_spinlock_t lock;
 32	struct clock_event_device ced;
 33	struct clocksource cs;
 34};
 35
 36#define STI_CONTROL 0x00
 37#define STI_COMPA_H 0x10
 38#define STI_COMPA_L 0x14
 39#define STI_COMPB_H 0x18
 40#define STI_COMPB_L 0x1c
 41#define STI_COUNT_H 0x20
 42#define STI_COUNT_L 0x24
 43#define STI_COUNT_RAW_H 0x28
 44#define STI_COUNT_RAW_L 0x2c
 45#define STI_SET_H 0x30
 46#define STI_SET_L 0x34
 47#define STI_INTSTATUS 0x40
 48#define STI_INTRAWSTATUS 0x44
 49#define STI_INTENSET 0x48
 50#define STI_INTENCLR 0x4c
 51#define STI_INTFFCLR 0x50
 52
 53static inline unsigned long em_sti_read(struct em_sti_priv *p, int offs)
 54{
 55	return ioread32(p->base + offs);
 56}
 57
 58static inline void em_sti_write(struct em_sti_priv *p, int offs,
 59				unsigned long value)
 60{
 61	iowrite32(value, p->base + offs);
 62}
 63
 64static int em_sti_enable(struct em_sti_priv *p)
 65{
 66	int ret;
 67
 68	/* enable clock */
 69	ret = clk_enable(p->clk);
 70	if (ret) {
 71		dev_err(&p->pdev->dev, "cannot enable clock\n");
 72		return ret;
 73	}
 74
 75	/* reset the counter */
 76	em_sti_write(p, STI_SET_H, 0x40000000);
 77	em_sti_write(p, STI_SET_L, 0x00000000);
 78
 79	/* mask and clear pending interrupts */
 80	em_sti_write(p, STI_INTENCLR, 3);
 81	em_sti_write(p, STI_INTFFCLR, 3);
 82
 83	/* enable updates of counter registers */
 84	em_sti_write(p, STI_CONTROL, 1);
 85
 86	return 0;
 87}
 88
 89static void em_sti_disable(struct em_sti_priv *p)
 90{
 91	/* mask interrupts */
 92	em_sti_write(p, STI_INTENCLR, 3);
 93
 94	/* stop clock */
 95	clk_disable(p->clk);
 96}
 97
 98static u64 em_sti_count(struct em_sti_priv *p)
 99{
100	u64 ticks;
101	unsigned long flags;
102
103	/* the STI hardware buffers the 48-bit count, but to
104	 * break it out into two 32-bit access the registers
105	 * must be accessed in a certain order.
106	 * Always read STI_COUNT_H before STI_COUNT_L.
107	 */
108	raw_spin_lock_irqsave(&p->lock, flags);
109	ticks = (u64)(em_sti_read(p, STI_COUNT_H) & 0xffff) << 32;
110	ticks |= em_sti_read(p, STI_COUNT_L);
111	raw_spin_unlock_irqrestore(&p->lock, flags);
112
113	return ticks;
114}
115
116static u64 em_sti_set_next(struct em_sti_priv *p, u64 next)
117{
118	unsigned long flags;
119
120	raw_spin_lock_irqsave(&p->lock, flags);
121
122	/* mask compare A interrupt */
123	em_sti_write(p, STI_INTENCLR, 1);
124
125	/* update compare A value */
126	em_sti_write(p, STI_COMPA_H, next >> 32);
127	em_sti_write(p, STI_COMPA_L, next & 0xffffffff);
128
129	/* clear compare A interrupt source */
130	em_sti_write(p, STI_INTFFCLR, 1);
131
132	/* unmask compare A interrupt */
133	em_sti_write(p, STI_INTENSET, 1);
134
135	raw_spin_unlock_irqrestore(&p->lock, flags);
136
137	return next;
138}
139
140static irqreturn_t em_sti_interrupt(int irq, void *dev_id)
141{
142	struct em_sti_priv *p = dev_id;
143
144	p->ced.event_handler(&p->ced);
145	return IRQ_HANDLED;
146}
147
148static int em_sti_start(struct em_sti_priv *p, unsigned int user)
149{
150	unsigned long flags;
151	int used_before;
152	int ret = 0;
153
154	raw_spin_lock_irqsave(&p->lock, flags);
155	used_before = p->active[USER_CLOCKSOURCE] | p->active[USER_CLOCKEVENT];
156	if (!used_before)
157		ret = em_sti_enable(p);
158
159	if (!ret)
160		p->active[user] = 1;
161	raw_spin_unlock_irqrestore(&p->lock, flags);
162
163	return ret;
164}
165
166static void em_sti_stop(struct em_sti_priv *p, unsigned int user)
167{
168	unsigned long flags;
169	int used_before, used_after;
170
171	raw_spin_lock_irqsave(&p->lock, flags);
172	used_before = p->active[USER_CLOCKSOURCE] | p->active[USER_CLOCKEVENT];
173	p->active[user] = 0;
174	used_after = p->active[USER_CLOCKSOURCE] | p->active[USER_CLOCKEVENT];
175
176	if (used_before && !used_after)
177		em_sti_disable(p);
178	raw_spin_unlock_irqrestore(&p->lock, flags);
179}
180
181static struct em_sti_priv *cs_to_em_sti(struct clocksource *cs)
182{
183	return container_of(cs, struct em_sti_priv, cs);
184}
185
186static u64 em_sti_clocksource_read(struct clocksource *cs)
187{
188	return em_sti_count(cs_to_em_sti(cs));
189}
190
191static int em_sti_clocksource_enable(struct clocksource *cs)
192{
193	struct em_sti_priv *p = cs_to_em_sti(cs);
194
195	return em_sti_start(p, USER_CLOCKSOURCE);
196}
197
198static void em_sti_clocksource_disable(struct clocksource *cs)
199{
200	em_sti_stop(cs_to_em_sti(cs), USER_CLOCKSOURCE);
201}
202
203static void em_sti_clocksource_resume(struct clocksource *cs)
204{
205	em_sti_clocksource_enable(cs);
206}
207
208static int em_sti_register_clocksource(struct em_sti_priv *p)
209{
210	struct clocksource *cs = &p->cs;
211
212	cs->name = dev_name(&p->pdev->dev);
213	cs->rating = 200;
214	cs->read = em_sti_clocksource_read;
215	cs->enable = em_sti_clocksource_enable;
216	cs->disable = em_sti_clocksource_disable;
217	cs->suspend = em_sti_clocksource_disable;
218	cs->resume = em_sti_clocksource_resume;
219	cs->mask = CLOCKSOURCE_MASK(48);
220	cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
221
222	dev_info(&p->pdev->dev, "used as clock source\n");
223
224	clocksource_register_hz(cs, p->rate);
225	return 0;
226}
227
228static struct em_sti_priv *ced_to_em_sti(struct clock_event_device *ced)
229{
230	return container_of(ced, struct em_sti_priv, ced);
231}
232
233static int em_sti_clock_event_shutdown(struct clock_event_device *ced)
234{
235	struct em_sti_priv *p = ced_to_em_sti(ced);
236	em_sti_stop(p, USER_CLOCKEVENT);
237	return 0;
238}
239
240static int em_sti_clock_event_set_oneshot(struct clock_event_device *ced)
241{
242	struct em_sti_priv *p = ced_to_em_sti(ced);
243
244	dev_info(&p->pdev->dev, "used for oneshot clock events\n");
245	em_sti_start(p, USER_CLOCKEVENT);
246	return 0;
247}
248
249static int em_sti_clock_event_next(unsigned long delta,
250				   struct clock_event_device *ced)
251{
252	struct em_sti_priv *p = ced_to_em_sti(ced);
253	u64 next;
254	int safe;
255
256	next = em_sti_set_next(p, em_sti_count(p) + delta);
257	safe = em_sti_count(p) < (next - 1);
258
259	return !safe;
260}
261
262static void em_sti_register_clockevent(struct em_sti_priv *p)
263{
264	struct clock_event_device *ced = &p->ced;
265
266	ced->name = dev_name(&p->pdev->dev);
267	ced->features = CLOCK_EVT_FEAT_ONESHOT;
268	ced->rating = 200;
269	ced->cpumask = cpu_possible_mask;
270	ced->set_next_event = em_sti_clock_event_next;
271	ced->set_state_shutdown = em_sti_clock_event_shutdown;
272	ced->set_state_oneshot = em_sti_clock_event_set_oneshot;
273
274	dev_info(&p->pdev->dev, "used for clock events\n");
275
276	clockevents_config_and_register(ced, p->rate, 2, 0xffffffff);
277}
278
279static int em_sti_probe(struct platform_device *pdev)
280{
281	struct em_sti_priv *p;
282	int irq, ret;
 
 
283
284	p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL);
285	if (p == NULL)
286		return -ENOMEM;
287
288	p->pdev = pdev;
289	platform_set_drvdata(pdev, p);
290
291	irq = platform_get_irq(pdev, 0);
292	if (irq < 0)
 
293		return irq;
 
294
295	/* map memory, let base point to the STI instance */
296	p->base = devm_platform_ioremap_resource(pdev, 0);
 
297	if (IS_ERR(p->base))
298		return PTR_ERR(p->base);
299
300	ret = devm_request_irq(&pdev->dev, irq, em_sti_interrupt,
301			       IRQF_TIMER | IRQF_IRQPOLL | IRQF_NOBALANCING,
302			       dev_name(&pdev->dev), p);
303	if (ret) {
304		dev_err(&pdev->dev, "failed to request low IRQ\n");
305		return ret;
306	}
307
308	/* get hold of clock */
309	p->clk = devm_clk_get(&pdev->dev, "sclk");
310	if (IS_ERR(p->clk)) {
311		dev_err(&pdev->dev, "cannot get clock\n");
312		return PTR_ERR(p->clk);
313	}
314
315	ret = clk_prepare(p->clk);
316	if (ret < 0) {
317		dev_err(&pdev->dev, "cannot prepare clock\n");
318		return ret;
319	}
320
321	ret = clk_enable(p->clk);
322	if (ret < 0) {
323		dev_err(&p->pdev->dev, "cannot enable clock\n");
324		clk_unprepare(p->clk);
325		return ret;
326	}
327	p->rate = clk_get_rate(p->clk);
328	clk_disable(p->clk);
329
330	raw_spin_lock_init(&p->lock);
331	em_sti_register_clockevent(p);
332	em_sti_register_clocksource(p);
333	return 0;
334}
335
 
 
 
 
 
336static const struct of_device_id em_sti_dt_ids[] = {
337	{ .compatible = "renesas,em-sti", },
338	{},
339};
340MODULE_DEVICE_TABLE(of, em_sti_dt_ids);
341
342static struct platform_driver em_sti_device_driver = {
343	.probe		= em_sti_probe,
 
344	.driver		= {
345		.name	= "em_sti",
346		.of_match_table = em_sti_dt_ids,
347		.suppress_bind_attrs = true,
348	}
349};
350
351static int __init em_sti_init(void)
352{
353	return platform_driver_register(&em_sti_device_driver);
354}
355
356static void __exit em_sti_exit(void)
357{
358	platform_driver_unregister(&em_sti_device_driver);
359}
360
361subsys_initcall(em_sti_init);
362module_exit(em_sti_exit);
363
364MODULE_AUTHOR("Magnus Damm");
365MODULE_DESCRIPTION("Renesas Emma Mobile STI Timer Driver");
v4.17
 
  1/*
  2 * Emma Mobile Timer Support - STI
  3 *
  4 *  Copyright (C) 2012 Magnus Damm
  5 *
  6 * This program is free software; you can redistribute it and/or modify
  7 * it under the terms of the GNU General Public License as published by
  8 * the Free Software Foundation; either version 2 of the License
  9 *
 10 * This program is distributed in the hope that it will be useful,
 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 13 * GNU General Public License for more details.
 14 *
 15 * You should have received a copy of the GNU General Public License
 16 * along with this program; if not, write to the Free Software
 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 18 */
 19
 20#include <linux/init.h>
 21#include <linux/platform_device.h>
 22#include <linux/spinlock.h>
 23#include <linux/interrupt.h>
 24#include <linux/ioport.h>
 25#include <linux/io.h>
 26#include <linux/clk.h>
 27#include <linux/irq.h>
 28#include <linux/err.h>
 29#include <linux/delay.h>
 30#include <linux/clocksource.h>
 31#include <linux/clockchips.h>
 32#include <linux/slab.h>
 33#include <linux/module.h>
 34
 35enum { USER_CLOCKSOURCE, USER_CLOCKEVENT, USER_NR };
 36
 37struct em_sti_priv {
 38	void __iomem *base;
 39	struct clk *clk;
 40	struct platform_device *pdev;
 41	unsigned int active[USER_NR];
 42	unsigned long rate;
 43	raw_spinlock_t lock;
 44	struct clock_event_device ced;
 45	struct clocksource cs;
 46};
 47
 48#define STI_CONTROL 0x00
 49#define STI_COMPA_H 0x10
 50#define STI_COMPA_L 0x14
 51#define STI_COMPB_H 0x18
 52#define STI_COMPB_L 0x1c
 53#define STI_COUNT_H 0x20
 54#define STI_COUNT_L 0x24
 55#define STI_COUNT_RAW_H 0x28
 56#define STI_COUNT_RAW_L 0x2c
 57#define STI_SET_H 0x30
 58#define STI_SET_L 0x34
 59#define STI_INTSTATUS 0x40
 60#define STI_INTRAWSTATUS 0x44
 61#define STI_INTENSET 0x48
 62#define STI_INTENCLR 0x4c
 63#define STI_INTFFCLR 0x50
 64
 65static inline unsigned long em_sti_read(struct em_sti_priv *p, int offs)
 66{
 67	return ioread32(p->base + offs);
 68}
 69
 70static inline void em_sti_write(struct em_sti_priv *p, int offs,
 71				unsigned long value)
 72{
 73	iowrite32(value, p->base + offs);
 74}
 75
 76static int em_sti_enable(struct em_sti_priv *p)
 77{
 78	int ret;
 79
 80	/* enable clock */
 81	ret = clk_enable(p->clk);
 82	if (ret) {
 83		dev_err(&p->pdev->dev, "cannot enable clock\n");
 84		return ret;
 85	}
 86
 87	/* reset the counter */
 88	em_sti_write(p, STI_SET_H, 0x40000000);
 89	em_sti_write(p, STI_SET_L, 0x00000000);
 90
 91	/* mask and clear pending interrupts */
 92	em_sti_write(p, STI_INTENCLR, 3);
 93	em_sti_write(p, STI_INTFFCLR, 3);
 94
 95	/* enable updates of counter registers */
 96	em_sti_write(p, STI_CONTROL, 1);
 97
 98	return 0;
 99}
100
101static void em_sti_disable(struct em_sti_priv *p)
102{
103	/* mask interrupts */
104	em_sti_write(p, STI_INTENCLR, 3);
105
106	/* stop clock */
107	clk_disable(p->clk);
108}
109
110static u64 em_sti_count(struct em_sti_priv *p)
111{
112	u64 ticks;
113	unsigned long flags;
114
115	/* the STI hardware buffers the 48-bit count, but to
116	 * break it out into two 32-bit access the registers
117	 * must be accessed in a certain order.
118	 * Always read STI_COUNT_H before STI_COUNT_L.
119	 */
120	raw_spin_lock_irqsave(&p->lock, flags);
121	ticks = (u64)(em_sti_read(p, STI_COUNT_H) & 0xffff) << 32;
122	ticks |= em_sti_read(p, STI_COUNT_L);
123	raw_spin_unlock_irqrestore(&p->lock, flags);
124
125	return ticks;
126}
127
128static u64 em_sti_set_next(struct em_sti_priv *p, u64 next)
129{
130	unsigned long flags;
131
132	raw_spin_lock_irqsave(&p->lock, flags);
133
134	/* mask compare A interrupt */
135	em_sti_write(p, STI_INTENCLR, 1);
136
137	/* update compare A value */
138	em_sti_write(p, STI_COMPA_H, next >> 32);
139	em_sti_write(p, STI_COMPA_L, next & 0xffffffff);
140
141	/* clear compare A interrupt source */
142	em_sti_write(p, STI_INTFFCLR, 1);
143
144	/* unmask compare A interrupt */
145	em_sti_write(p, STI_INTENSET, 1);
146
147	raw_spin_unlock_irqrestore(&p->lock, flags);
148
149	return next;
150}
151
152static irqreturn_t em_sti_interrupt(int irq, void *dev_id)
153{
154	struct em_sti_priv *p = dev_id;
155
156	p->ced.event_handler(&p->ced);
157	return IRQ_HANDLED;
158}
159
160static int em_sti_start(struct em_sti_priv *p, unsigned int user)
161{
162	unsigned long flags;
163	int used_before;
164	int ret = 0;
165
166	raw_spin_lock_irqsave(&p->lock, flags);
167	used_before = p->active[USER_CLOCKSOURCE] | p->active[USER_CLOCKEVENT];
168	if (!used_before)
169		ret = em_sti_enable(p);
170
171	if (!ret)
172		p->active[user] = 1;
173	raw_spin_unlock_irqrestore(&p->lock, flags);
174
175	return ret;
176}
177
178static void em_sti_stop(struct em_sti_priv *p, unsigned int user)
179{
180	unsigned long flags;
181	int used_before, used_after;
182
183	raw_spin_lock_irqsave(&p->lock, flags);
184	used_before = p->active[USER_CLOCKSOURCE] | p->active[USER_CLOCKEVENT];
185	p->active[user] = 0;
186	used_after = p->active[USER_CLOCKSOURCE] | p->active[USER_CLOCKEVENT];
187
188	if (used_before && !used_after)
189		em_sti_disable(p);
190	raw_spin_unlock_irqrestore(&p->lock, flags);
191}
192
193static struct em_sti_priv *cs_to_em_sti(struct clocksource *cs)
194{
195	return container_of(cs, struct em_sti_priv, cs);
196}
197
198static u64 em_sti_clocksource_read(struct clocksource *cs)
199{
200	return em_sti_count(cs_to_em_sti(cs));
201}
202
203static int em_sti_clocksource_enable(struct clocksource *cs)
204{
205	struct em_sti_priv *p = cs_to_em_sti(cs);
206
207	return em_sti_start(p, USER_CLOCKSOURCE);
208}
209
210static void em_sti_clocksource_disable(struct clocksource *cs)
211{
212	em_sti_stop(cs_to_em_sti(cs), USER_CLOCKSOURCE);
213}
214
215static void em_sti_clocksource_resume(struct clocksource *cs)
216{
217	em_sti_clocksource_enable(cs);
218}
219
220static int em_sti_register_clocksource(struct em_sti_priv *p)
221{
222	struct clocksource *cs = &p->cs;
223
224	cs->name = dev_name(&p->pdev->dev);
225	cs->rating = 200;
226	cs->read = em_sti_clocksource_read;
227	cs->enable = em_sti_clocksource_enable;
228	cs->disable = em_sti_clocksource_disable;
229	cs->suspend = em_sti_clocksource_disable;
230	cs->resume = em_sti_clocksource_resume;
231	cs->mask = CLOCKSOURCE_MASK(48);
232	cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
233
234	dev_info(&p->pdev->dev, "used as clock source\n");
235
236	clocksource_register_hz(cs, p->rate);
237	return 0;
238}
239
240static struct em_sti_priv *ced_to_em_sti(struct clock_event_device *ced)
241{
242	return container_of(ced, struct em_sti_priv, ced);
243}
244
245static int em_sti_clock_event_shutdown(struct clock_event_device *ced)
246{
247	struct em_sti_priv *p = ced_to_em_sti(ced);
248	em_sti_stop(p, USER_CLOCKEVENT);
249	return 0;
250}
251
252static int em_sti_clock_event_set_oneshot(struct clock_event_device *ced)
253{
254	struct em_sti_priv *p = ced_to_em_sti(ced);
255
256	dev_info(&p->pdev->dev, "used for oneshot clock events\n");
257	em_sti_start(p, USER_CLOCKEVENT);
258	return 0;
259}
260
261static int em_sti_clock_event_next(unsigned long delta,
262				   struct clock_event_device *ced)
263{
264	struct em_sti_priv *p = ced_to_em_sti(ced);
265	u64 next;
266	int safe;
267
268	next = em_sti_set_next(p, em_sti_count(p) + delta);
269	safe = em_sti_count(p) < (next - 1);
270
271	return !safe;
272}
273
274static void em_sti_register_clockevent(struct em_sti_priv *p)
275{
276	struct clock_event_device *ced = &p->ced;
277
278	ced->name = dev_name(&p->pdev->dev);
279	ced->features = CLOCK_EVT_FEAT_ONESHOT;
280	ced->rating = 200;
281	ced->cpumask = cpu_possible_mask;
282	ced->set_next_event = em_sti_clock_event_next;
283	ced->set_state_shutdown = em_sti_clock_event_shutdown;
284	ced->set_state_oneshot = em_sti_clock_event_set_oneshot;
285
286	dev_info(&p->pdev->dev, "used for clock events\n");
287
288	clockevents_config_and_register(ced, p->rate, 2, 0xffffffff);
289}
290
291static int em_sti_probe(struct platform_device *pdev)
292{
293	struct em_sti_priv *p;
294	struct resource *res;
295	int irq;
296	int ret;
297
298	p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL);
299	if (p == NULL)
300		return -ENOMEM;
301
302	p->pdev = pdev;
303	platform_set_drvdata(pdev, p);
304
305	irq = platform_get_irq(pdev, 0);
306	if (irq < 0) {
307		dev_err(&pdev->dev, "failed to get irq\n");
308		return irq;
309	}
310
311	/* map memory, let base point to the STI instance */
312	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
313	p->base = devm_ioremap_resource(&pdev->dev, res);
314	if (IS_ERR(p->base))
315		return PTR_ERR(p->base);
316
317	ret = devm_request_irq(&pdev->dev, irq, em_sti_interrupt,
318			       IRQF_TIMER | IRQF_IRQPOLL | IRQF_NOBALANCING,
319			       dev_name(&pdev->dev), p);
320	if (ret) {
321		dev_err(&pdev->dev, "failed to request low IRQ\n");
322		return ret;
323	}
324
325	/* get hold of clock */
326	p->clk = devm_clk_get(&pdev->dev, "sclk");
327	if (IS_ERR(p->clk)) {
328		dev_err(&pdev->dev, "cannot get clock\n");
329		return PTR_ERR(p->clk);
330	}
331
332	ret = clk_prepare(p->clk);
333	if (ret < 0) {
334		dev_err(&pdev->dev, "cannot prepare clock\n");
335		return ret;
336	}
337
338	ret = clk_enable(p->clk);
339	if (ret < 0) {
340		dev_err(&p->pdev->dev, "cannot enable clock\n");
341		clk_unprepare(p->clk);
342		return ret;
343	}
344	p->rate = clk_get_rate(p->clk);
345	clk_disable(p->clk);
346
347	raw_spin_lock_init(&p->lock);
348	em_sti_register_clockevent(p);
349	em_sti_register_clocksource(p);
350	return 0;
351}
352
353static int em_sti_remove(struct platform_device *pdev)
354{
355	return -EBUSY; /* cannot unregister clockevent and clocksource */
356}
357
358static const struct of_device_id em_sti_dt_ids[] = {
359	{ .compatible = "renesas,em-sti", },
360	{},
361};
362MODULE_DEVICE_TABLE(of, em_sti_dt_ids);
363
364static struct platform_driver em_sti_device_driver = {
365	.probe		= em_sti_probe,
366	.remove		= em_sti_remove,
367	.driver		= {
368		.name	= "em_sti",
369		.of_match_table = em_sti_dt_ids,
 
370	}
371};
372
373static int __init em_sti_init(void)
374{
375	return platform_driver_register(&em_sti_device_driver);
376}
377
378static void __exit em_sti_exit(void)
379{
380	platform_driver_unregister(&em_sti_device_driver);
381}
382
383subsys_initcall(em_sti_init);
384module_exit(em_sti_exit);
385
386MODULE_AUTHOR("Magnus Damm");
387MODULE_DESCRIPTION("Renesas Emma Mobile STI Timer Driver");
388MODULE_LICENSE("GPL v2");