tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * TX4939 internal RTC driver
3 * Based on RBTX49xx patch from CELF patch archive.
4 *
5 * This file is subject to the terms and conditions of the GNU General Public
6 * License. See the file "COPYING" in the main directory of this archive
7 * for more details.
8 *
9 * (C) Copyright TOSHIBA CORPORATION 2005-2007
10 */
11#include <linux/rtc.h>
12#include <linux/platform_device.h>
13#include <linux/interrupt.h>
14#include <linux/io.h>
15#include <asm/txx9/tx4939.h>
16
17struct tx4939rtc_plat_data {
18 struct rtc_device *rtc;
19 struct tx4939_rtc_reg __iomem *rtcreg;
20};
21
22static struct tx4939rtc_plat_data *get_tx4939rtc_plat_data(struct device *dev)
23{
24 return platform_get_drvdata(to_platform_device(dev));
25}
26
27static int tx4939_rtc_cmd(struct tx4939_rtc_reg __iomem *rtcreg, int cmd)
28{
29 int i = 0;
30
31 __raw_writel(cmd, &rtcreg->ctl);
32 /* This might take 30us (next 32.768KHz clock) */
33 while (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_BUSY) {
34 /* timeout on approx. 100us (@ GBUS200MHz) */
35 if (i++ > 200 * 100)
36 return -EBUSY;
37 cpu_relax();
38 }
39 return 0;
40}
41
42static int tx4939_rtc_set_mmss(struct device *dev, unsigned long secs)
43{
44 struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev);
45 struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg;
46 int i, ret;
47 unsigned char buf[6];
48
49 buf[0] = 0;
50 buf[1] = 0;
51 buf[2] = secs;
52 buf[3] = secs >> 8;
53 buf[4] = secs >> 16;
54 buf[5] = secs >> 24;
55 spin_lock_irq(&pdata->rtc->irq_lock);
56 __raw_writel(0, &rtcreg->adr);
57 for (i = 0; i < 6; i++)
58 __raw_writel(buf[i], &rtcreg->dat);
59 ret = tx4939_rtc_cmd(rtcreg,
60 TX4939_RTCCTL_COMMAND_SETTIME |
61 (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALME));
62 spin_unlock_irq(&pdata->rtc->irq_lock);
63 return ret;
64}
65
66static int tx4939_rtc_read_time(struct device *dev, struct rtc_time *tm)
67{
68 struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev);
69 struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg;
70 int i, ret;
71 unsigned long sec;
72 unsigned char buf[6];
73
74 spin_lock_irq(&pdata->rtc->irq_lock);
75 ret = tx4939_rtc_cmd(rtcreg,
76 TX4939_RTCCTL_COMMAND_GETTIME |
77 (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALME));
78 if (ret) {
79 spin_unlock_irq(&pdata->rtc->irq_lock);
80 return ret;
81 }
82 __raw_writel(2, &rtcreg->adr);
83 for (i = 2; i < 6; i++)
84 buf[i] = __raw_readl(&rtcreg->dat);
85 spin_unlock_irq(&pdata->rtc->irq_lock);
86 sec = (buf[5] << 24) | (buf[4] << 16) | (buf[3] << 8) | buf[2];
87 rtc_time_to_tm(sec, tm);
88 return rtc_valid_tm(tm);
89}
90
91static int tx4939_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
92{
93 struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev);
94 struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg;
95 int i, ret;
96 unsigned long sec;
97 unsigned char buf[6];
98
99 if (alrm->time.tm_sec < 0 ||
100 alrm->time.tm_min < 0 ||
101 alrm->time.tm_hour < 0 ||
102 alrm->time.tm_mday < 0 ||
103 alrm->time.tm_mon < 0 ||
104 alrm->time.tm_year < 0)
105 return -EINVAL;
106 rtc_tm_to_time(&alrm->time, &sec);
107 buf[0] = 0;
108 buf[1] = 0;
109 buf[2] = sec;
110 buf[3] = sec >> 8;
111 buf[4] = sec >> 16;
112 buf[5] = sec >> 24;
113 spin_lock_irq(&pdata->rtc->irq_lock);
114 __raw_writel(0, &rtcreg->adr);
115 for (i = 0; i < 6; i++)
116 __raw_writel(buf[i], &rtcreg->dat);
117 ret = tx4939_rtc_cmd(rtcreg, TX4939_RTCCTL_COMMAND_SETALARM |
118 (alrm->enabled ? TX4939_RTCCTL_ALME : 0));
119 spin_unlock_irq(&pdata->rtc->irq_lock);
120 return ret;
121}
122
123static int tx4939_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
124{
125 struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev);
126 struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg;
127 int i, ret;
128 unsigned long sec;
129 unsigned char buf[6];
130 u32 ctl;
131
132 spin_lock_irq(&pdata->rtc->irq_lock);
133 ret = tx4939_rtc_cmd(rtcreg,
134 TX4939_RTCCTL_COMMAND_GETALARM |
135 (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALME));
136 if (ret) {
137 spin_unlock_irq(&pdata->rtc->irq_lock);
138 return ret;
139 }
140 __raw_writel(2, &rtcreg->adr);
141 for (i = 2; i < 6; i++)
142 buf[i] = __raw_readl(&rtcreg->dat);
143 ctl = __raw_readl(&rtcreg->ctl);
144 alrm->enabled = (ctl & TX4939_RTCCTL_ALME) ? 1 : 0;
145 alrm->pending = (ctl & TX4939_RTCCTL_ALMD) ? 1 : 0;
146 spin_unlock_irq(&pdata->rtc->irq_lock);
147 sec = (buf[5] << 24) | (buf[4] << 16) | (buf[3] << 8) | buf[2];
148 rtc_time_to_tm(sec, &alrm->time);
149 return rtc_valid_tm(&alrm->time);
150}
151
152static int tx4939_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
153{
154 struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev);
155
156 spin_lock_irq(&pdata->rtc->irq_lock);
157 tx4939_rtc_cmd(pdata->rtcreg,
158 TX4939_RTCCTL_COMMAND_NOP |
159 (enabled ? TX4939_RTCCTL_ALME : 0));
160 spin_unlock_irq(&pdata->rtc->irq_lock);
161 return 0;
162}
163
164static irqreturn_t tx4939_rtc_interrupt(int irq, void *dev_id)
165{
166 struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev_id);
167 struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg;
168 unsigned long events = RTC_IRQF;
169
170 spin_lock(&pdata->rtc->irq_lock);
171 if (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALMD) {
172 events |= RTC_AF;
173 tx4939_rtc_cmd(rtcreg, TX4939_RTCCTL_COMMAND_NOP);
174 }
175 spin_unlock(&pdata->rtc->irq_lock);
176 rtc_update_irq(pdata->rtc, 1, events);
177 return IRQ_HANDLED;
178}
179
180static const struct rtc_class_ops tx4939_rtc_ops = {
181 .read_time = tx4939_rtc_read_time,
182 .read_alarm = tx4939_rtc_read_alarm,
183 .set_alarm = tx4939_rtc_set_alarm,
184 .set_mmss = tx4939_rtc_set_mmss,
185 .alarm_irq_enable = tx4939_rtc_alarm_irq_enable,
186};
187
188static ssize_t tx4939_rtc_nvram_read(struct kobject *kobj,
189 struct bin_attribute *bin_attr,
190 char *buf, loff_t pos, size_t size)
191{
192 struct device *dev = container_of(kobj, struct device, kobj);
193 struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev);
194 struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg;
195 ssize_t count;
196
197 spin_lock_irq(&pdata->rtc->irq_lock);
198 for (count = 0; size > 0 && pos < TX4939_RTC_REG_RAMSIZE;
199 count++, size--) {
200 __raw_writel(pos++, &rtcreg->adr);
201 *buf++ = __raw_readl(&rtcreg->dat);
202 }
203 spin_unlock_irq(&pdata->rtc->irq_lock);
204 return count;
205}
206
207static ssize_t tx4939_rtc_nvram_write(struct kobject *kobj,
208 struct bin_attribute *bin_attr,
209 char *buf, loff_t pos, size_t size)
210{
211 struct device *dev = container_of(kobj, struct device, kobj);
212 struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev);
213 struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg;
214 ssize_t count;
215
216 spin_lock_irq(&pdata->rtc->irq_lock);
217 for (count = 0; size > 0 && pos < TX4939_RTC_REG_RAMSIZE;
218 count++, size--) {
219 __raw_writel(pos++, &rtcreg->adr);
220 __raw_writel(*buf++, &rtcreg->dat);
221 }
222 spin_unlock_irq(&pdata->rtc->irq_lock);
223 return count;
224}
225
226static struct bin_attribute tx4939_rtc_nvram_attr = {
227 .attr = {
228 .name = "nvram",
229 .mode = S_IRUGO | S_IWUSR,
230 },
231 .size = TX4939_RTC_REG_RAMSIZE,
232 .read = tx4939_rtc_nvram_read,
233 .write = tx4939_rtc_nvram_write,
234};
235
236static int __init tx4939_rtc_probe(struct platform_device *pdev)
237{
238 struct rtc_device *rtc;
239 struct tx4939rtc_plat_data *pdata;
240 struct resource *res;
241 int irq, ret;
242
243 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
244 if (!res)
245 return -ENODEV;
246 irq = platform_get_irq(pdev, 0);
247 if (irq < 0)
248 return -ENODEV;
249 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
250 if (!pdata)
251 return -ENOMEM;
252 platform_set_drvdata(pdev, pdata);
253
254 if (!devm_request_mem_region(&pdev->dev, res->start,
255 resource_size(res), pdev->name))
256 return -EBUSY;
257 pdata->rtcreg = devm_ioremap(&pdev->dev, res->start,
258 resource_size(res));
259 if (!pdata->rtcreg)
260 return -EBUSY;
261
262 tx4939_rtc_cmd(pdata->rtcreg, TX4939_RTCCTL_COMMAND_NOP);
263 if (devm_request_irq(&pdev->dev, irq, tx4939_rtc_interrupt,
264 IRQF_DISABLED, pdev->name, &pdev->dev) < 0)
265 return -EBUSY;
266 rtc = rtc_device_register(pdev->name, &pdev->dev,
267 &tx4939_rtc_ops, THIS_MODULE);
268 if (IS_ERR(rtc))
269 return PTR_ERR(rtc);
270 pdata->rtc = rtc;
271 ret = sysfs_create_bin_file(&pdev->dev.kobj, &tx4939_rtc_nvram_attr);
272 if (ret)
273 rtc_device_unregister(rtc);
274 return ret;
275}
276
277static int __exit tx4939_rtc_remove(struct platform_device *pdev)
278{
279 struct tx4939rtc_plat_data *pdata = platform_get_drvdata(pdev);
280 struct rtc_device *rtc = pdata->rtc;
281
282 spin_lock_irq(&rtc->irq_lock);
283 tx4939_rtc_cmd(pdata->rtcreg, TX4939_RTCCTL_COMMAND_NOP);
284 spin_unlock_irq(&rtc->irq_lock);
285 sysfs_remove_bin_file(&pdev->dev.kobj, &tx4939_rtc_nvram_attr);
286 rtc_device_unregister(rtc);
287 platform_set_drvdata(pdev, NULL);
288 return 0;
289}
290
291static struct platform_driver tx4939_rtc_driver = {
292 .remove = __exit_p(tx4939_rtc_remove),
293 .driver = {
294 .name = "tx4939rtc",
295 .owner = THIS_MODULE,
296 },
297};
298
299static int __init tx4939rtc_init(void)
300{
301 return platform_driver_probe(&tx4939_rtc_driver, tx4939_rtc_probe);
302}
303
304static void __exit tx4939rtc_exit(void)
305{
306 platform_driver_unregister(&tx4939_rtc_driver);
307}
308
309module_init(tx4939rtc_init);
310module_exit(tx4939rtc_exit);
311
312MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
313MODULE_DESCRIPTION("TX4939 internal RTC driver");
314MODULE_LICENSE("GPL");
315MODULE_ALIAS("platform:tx4939rtc");