Commit | Line | Data |
---|---|---|
7dc679ef | 1 | // SPDX-License-Identifier: GPL-2.0 |
453b4c6d JJ |
2 | /* |
3 | * MOXA ART RTC driver. | |
4 | * | |
5 | * Copyright (C) 2013 Jonas Jensen | |
6 | * | |
7 | * Jonas Jensen <jonas.jensen@gmail.com> | |
8 | * | |
9 | * Based on code from | |
10 | * Moxa Technology Co., Ltd. <www.moxa.com> | |
453b4c6d JJ |
11 | */ |
12 | ||
2985cda8 | 13 | #include <linux/err.h> |
453b4c6d JJ |
14 | #include <linux/init.h> |
15 | #include <linux/kernel.h> | |
16 | #include <linux/delay.h> | |
17 | #include <linux/rtc.h> | |
18 | #include <linux/platform_device.h> | |
19 | #include <linux/module.h> | |
2985cda8 DT |
20 | #include <linux/mod_devicetable.h> |
21 | #include <linux/gpio/consumer.h> | |
453b4c6d JJ |
22 | |
23 | #define GPIO_RTC_RESERVED 0x0C | |
24 | #define GPIO_RTC_DATA_SET 0x10 | |
25 | #define GPIO_RTC_DATA_CLEAR 0x14 | |
26 | #define GPIO_RTC_PIN_PULL_ENABLE 0x18 | |
27 | #define GPIO_RTC_PIN_PULL_TYPE 0x1C | |
28 | #define GPIO_RTC_INT_ENABLE 0x20 | |
29 | #define GPIO_RTC_INT_RAW_STATE 0x24 | |
30 | #define GPIO_RTC_INT_MASKED_STATE 0x28 | |
31 | #define GPIO_RTC_INT_MASK 0x2C | |
32 | #define GPIO_RTC_INT_CLEAR 0x30 | |
33 | #define GPIO_RTC_INT_TRIGGER 0x34 | |
34 | #define GPIO_RTC_INT_BOTH 0x38 | |
35 | #define GPIO_RTC_INT_RISE_NEG 0x3C | |
36 | #define GPIO_RTC_BOUNCE_ENABLE 0x40 | |
37 | #define GPIO_RTC_BOUNCE_PRE_SCALE 0x44 | |
38 | #define GPIO_RTC_PROTECT_W 0x8E | |
39 | #define GPIO_RTC_PROTECT_R 0x8F | |
40 | #define GPIO_RTC_YEAR_W 0x8C | |
41 | #define GPIO_RTC_YEAR_R 0x8D | |
42 | #define GPIO_RTC_DAY_W 0x8A | |
43 | #define GPIO_RTC_DAY_R 0x8B | |
44 | #define GPIO_RTC_MONTH_W 0x88 | |
45 | #define GPIO_RTC_MONTH_R 0x89 | |
46 | #define GPIO_RTC_DATE_W 0x86 | |
47 | #define GPIO_RTC_DATE_R 0x87 | |
48 | #define GPIO_RTC_HOURS_W 0x84 | |
49 | #define GPIO_RTC_HOURS_R 0x85 | |
50 | #define GPIO_RTC_MINUTES_W 0x82 | |
51 | #define GPIO_RTC_MINUTES_R 0x83 | |
52 | #define GPIO_RTC_SECONDS_W 0x80 | |
53 | #define GPIO_RTC_SECONDS_R 0x81 | |
54 | #define GPIO_RTC_DELAY_TIME 8 | |
55 | ||
56 | struct moxart_rtc { | |
57 | struct rtc_device *rtc; | |
58 | spinlock_t rtc_lock; | |
2985cda8 DT |
59 | struct gpio_desc *gpio_data; |
60 | struct gpio_desc *gpio_sclk; | |
61 | struct gpio_desc *gpio_reset; | |
453b4c6d JJ |
62 | }; |
63 | ||
64 | static int day_of_year[12] = { 0, 31, 59, 90, 120, 151, 181, | |
65 | 212, 243, 273, 304, 334 }; | |
66 | ||
67 | static void moxart_rtc_write_byte(struct device *dev, u8 data) | |
68 | { | |
69 | struct moxart_rtc *moxart_rtc = dev_get_drvdata(dev); | |
70 | int i; | |
71 | ||
72 | for (i = 0; i < 8; i++, data >>= 1) { | |
2985cda8 DT |
73 | gpiod_set_value(moxart_rtc->gpio_sclk, 0); |
74 | gpiod_set_value(moxart_rtc->gpio_data, ((data & 1) == 1)); | |
453b4c6d | 75 | udelay(GPIO_RTC_DELAY_TIME); |
2985cda8 | 76 | gpiod_set_value(moxart_rtc->gpio_sclk, 1); |
453b4c6d JJ |
77 | udelay(GPIO_RTC_DELAY_TIME); |
78 | } | |
79 | } | |
80 | ||
81 | static u8 moxart_rtc_read_byte(struct device *dev) | |
82 | { | |
83 | struct moxart_rtc *moxart_rtc = dev_get_drvdata(dev); | |
84 | int i; | |
85 | u8 data = 0; | |
86 | ||
87 | for (i = 0; i < 8; i++) { | |
2985cda8 | 88 | gpiod_set_value(moxart_rtc->gpio_sclk, 0); |
453b4c6d | 89 | udelay(GPIO_RTC_DELAY_TIME); |
2985cda8 | 90 | gpiod_set_value(moxart_rtc->gpio_sclk, 1); |
453b4c6d | 91 | udelay(GPIO_RTC_DELAY_TIME); |
2985cda8 | 92 | if (gpiod_get_value(moxart_rtc->gpio_data)) |
453b4c6d JJ |
93 | data |= (1 << i); |
94 | udelay(GPIO_RTC_DELAY_TIME); | |
95 | } | |
96 | return data; | |
97 | } | |
98 | ||
99 | static u8 moxart_rtc_read_register(struct device *dev, u8 cmd) | |
100 | { | |
101 | struct moxart_rtc *moxart_rtc = dev_get_drvdata(dev); | |
102 | u8 data; | |
103 | unsigned long flags; | |
104 | ||
105 | local_irq_save(flags); | |
106 | ||
2985cda8 DT |
107 | gpiod_direction_output(moxart_rtc->gpio_data, 0); |
108 | gpiod_set_value(moxart_rtc->gpio_reset, 1); | |
453b4c6d JJ |
109 | udelay(GPIO_RTC_DELAY_TIME); |
110 | moxart_rtc_write_byte(dev, cmd); | |
2985cda8 | 111 | gpiod_direction_input(moxart_rtc->gpio_data); |
453b4c6d JJ |
112 | udelay(GPIO_RTC_DELAY_TIME); |
113 | data = moxart_rtc_read_byte(dev); | |
2985cda8 DT |
114 | gpiod_set_value(moxart_rtc->gpio_sclk, 0); |
115 | gpiod_set_value(moxart_rtc->gpio_reset, 0); | |
453b4c6d JJ |
116 | udelay(GPIO_RTC_DELAY_TIME); |
117 | ||
118 | local_irq_restore(flags); | |
119 | ||
120 | return data; | |
121 | } | |
122 | ||
123 | static void moxart_rtc_write_register(struct device *dev, u8 cmd, u8 data) | |
124 | { | |
125 | struct moxart_rtc *moxart_rtc = dev_get_drvdata(dev); | |
126 | unsigned long flags; | |
127 | ||
128 | local_irq_save(flags); | |
129 | ||
2985cda8 DT |
130 | gpiod_direction_output(moxart_rtc->gpio_data, 0); |
131 | gpiod_set_value(moxart_rtc->gpio_reset, 1); | |
453b4c6d JJ |
132 | udelay(GPIO_RTC_DELAY_TIME); |
133 | moxart_rtc_write_byte(dev, cmd); | |
134 | moxart_rtc_write_byte(dev, data); | |
2985cda8 DT |
135 | gpiod_set_value(moxart_rtc->gpio_sclk, 0); |
136 | gpiod_set_value(moxart_rtc->gpio_reset, 0); | |
453b4c6d JJ |
137 | udelay(GPIO_RTC_DELAY_TIME); |
138 | ||
139 | local_irq_restore(flags); | |
140 | } | |
141 | ||
142 | static int moxart_rtc_set_time(struct device *dev, struct rtc_time *tm) | |
143 | { | |
144 | struct moxart_rtc *moxart_rtc = dev_get_drvdata(dev); | |
145 | ||
146 | spin_lock_irq(&moxart_rtc->rtc_lock); | |
147 | ||
148 | moxart_rtc_write_register(dev, GPIO_RTC_PROTECT_W, 0); | |
149 | moxart_rtc_write_register(dev, GPIO_RTC_YEAR_W, | |
150 | (((tm->tm_year - 100) / 10) << 4) | | |
151 | ((tm->tm_year - 100) % 10)); | |
152 | ||
153 | moxart_rtc_write_register(dev, GPIO_RTC_MONTH_W, | |
154 | (((tm->tm_mon + 1) / 10) << 4) | | |
155 | ((tm->tm_mon + 1) % 10)); | |
156 | ||
157 | moxart_rtc_write_register(dev, GPIO_RTC_DATE_W, | |
158 | ((tm->tm_mday / 10) << 4) | | |
159 | (tm->tm_mday % 10)); | |
160 | ||
161 | moxart_rtc_write_register(dev, GPIO_RTC_HOURS_W, | |
162 | ((tm->tm_hour / 10) << 4) | | |
163 | (tm->tm_hour % 10)); | |
164 | ||
165 | moxart_rtc_write_register(dev, GPIO_RTC_MINUTES_W, | |
166 | ((tm->tm_min / 10) << 4) | | |
167 | (tm->tm_min % 10)); | |
168 | ||
169 | moxart_rtc_write_register(dev, GPIO_RTC_SECONDS_W, | |
170 | ((tm->tm_sec / 10) << 4) | | |
171 | (tm->tm_sec % 10)); | |
172 | ||
173 | moxart_rtc_write_register(dev, GPIO_RTC_PROTECT_W, 0x80); | |
174 | ||
175 | spin_unlock_irq(&moxart_rtc->rtc_lock); | |
176 | ||
177 | dev_dbg(dev, "%s: success tm_year=%d tm_mon=%d\n" | |
178 | "tm_mday=%d tm_hour=%d tm_min=%d tm_sec=%d\n", | |
179 | __func__, tm->tm_year, tm->tm_mon, tm->tm_mday, | |
180 | tm->tm_hour, tm->tm_min, tm->tm_sec); | |
181 | ||
182 | return 0; | |
183 | } | |
184 | ||
185 | static int moxart_rtc_read_time(struct device *dev, struct rtc_time *tm) | |
186 | { | |
187 | struct moxart_rtc *moxart_rtc = dev_get_drvdata(dev); | |
188 | unsigned char v; | |
189 | ||
190 | spin_lock_irq(&moxart_rtc->rtc_lock); | |
191 | ||
192 | v = moxart_rtc_read_register(dev, GPIO_RTC_SECONDS_R); | |
193 | tm->tm_sec = (((v & 0x70) >> 4) * 10) + (v & 0x0F); | |
194 | ||
195 | v = moxart_rtc_read_register(dev, GPIO_RTC_MINUTES_R); | |
196 | tm->tm_min = (((v & 0x70) >> 4) * 10) + (v & 0x0F); | |
197 | ||
198 | v = moxart_rtc_read_register(dev, GPIO_RTC_HOURS_R); | |
199 | if (v & 0x80) { /* 12-hour mode */ | |
200 | tm->tm_hour = (((v & 0x10) >> 4) * 10) + (v & 0x0F); | |
201 | if (v & 0x20) { /* PM mode */ | |
202 | tm->tm_hour += 12; | |
203 | if (tm->tm_hour >= 24) | |
204 | tm->tm_hour = 0; | |
205 | } | |
206 | } else { /* 24-hour mode */ | |
207 | tm->tm_hour = (((v & 0x30) >> 4) * 10) + (v & 0x0F); | |
208 | } | |
209 | ||
210 | v = moxart_rtc_read_register(dev, GPIO_RTC_DATE_R); | |
211 | tm->tm_mday = (((v & 0x30) >> 4) * 10) + (v & 0x0F); | |
212 | ||
213 | v = moxart_rtc_read_register(dev, GPIO_RTC_MONTH_R); | |
214 | tm->tm_mon = (((v & 0x10) >> 4) * 10) + (v & 0x0F); | |
215 | tm->tm_mon--; | |
216 | ||
217 | v = moxart_rtc_read_register(dev, GPIO_RTC_YEAR_R); | |
218 | tm->tm_year = (((v & 0xF0) >> 4) * 10) + (v & 0x0F); | |
219 | tm->tm_year += 100; | |
220 | if (tm->tm_year <= 69) | |
221 | tm->tm_year += 100; | |
222 | ||
223 | v = moxart_rtc_read_register(dev, GPIO_RTC_DAY_R); | |
224 | tm->tm_wday = (v & 0x0f) - 1; | |
225 | tm->tm_yday = day_of_year[tm->tm_mon]; | |
226 | tm->tm_yday += (tm->tm_mday - 1); | |
227 | if (tm->tm_mon >= 2) { | |
228 | if (!(tm->tm_year % 4) && (tm->tm_year % 100)) | |
229 | tm->tm_yday++; | |
230 | } | |
231 | ||
232 | tm->tm_isdst = 0; | |
233 | ||
234 | spin_unlock_irq(&moxart_rtc->rtc_lock); | |
235 | ||
236 | return 0; | |
237 | } | |
238 | ||
239 | static const struct rtc_class_ops moxart_rtc_ops = { | |
240 | .read_time = moxart_rtc_read_time, | |
241 | .set_time = moxart_rtc_set_time, | |
242 | }; | |
243 | ||
244 | static int moxart_rtc_probe(struct platform_device *pdev) | |
245 | { | |
246 | struct moxart_rtc *moxart_rtc; | |
247 | int ret = 0; | |
248 | ||
249 | moxart_rtc = devm_kzalloc(&pdev->dev, sizeof(*moxart_rtc), GFP_KERNEL); | |
4410af6e | 250 | if (!moxart_rtc) |
453b4c6d | 251 | return -ENOMEM; |
453b4c6d | 252 | |
2985cda8 DT |
253 | moxart_rtc->gpio_data = devm_gpiod_get(&pdev->dev, "rtc-data", |
254 | GPIOD_IN); | |
255 | ret = PTR_ERR_OR_ZERO(moxart_rtc->gpio_data); | |
453b4c6d | 256 | if (ret) { |
2985cda8 | 257 | dev_err(&pdev->dev, "can't get rtc data gpio: %d\n", ret); |
453b4c6d JJ |
258 | return ret; |
259 | } | |
260 | ||
2985cda8 DT |
261 | moxart_rtc->gpio_sclk = devm_gpiod_get(&pdev->dev, "rtc-sclk", |
262 | GPIOD_ASIS); | |
263 | ret = PTR_ERR_OR_ZERO(moxart_rtc->gpio_sclk); | |
453b4c6d | 264 | if (ret) { |
2985cda8 | 265 | dev_err(&pdev->dev, "can't get rtc sclk gpio: %d\n", ret); |
453b4c6d JJ |
266 | return ret; |
267 | } | |
268 | ||
2985cda8 DT |
269 | moxart_rtc->gpio_reset = devm_gpiod_get(&pdev->dev, "rtc-reset", |
270 | GPIOD_ASIS); | |
271 | ret = PTR_ERR_OR_ZERO(moxart_rtc->gpio_reset); | |
453b4c6d | 272 | if (ret) { |
2985cda8 | 273 | dev_err(&pdev->dev, "can't get rtc reset gpio: %d\n", ret); |
453b4c6d JJ |
274 | return ret; |
275 | } | |
276 | ||
2985cda8 DT |
277 | spin_lock_init(&moxart_rtc->rtc_lock); |
278 | platform_set_drvdata(pdev, moxart_rtc); | |
279 | ||
453b4c6d JJ |
280 | moxart_rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name, |
281 | &moxart_rtc_ops, | |
282 | THIS_MODULE); | |
283 | if (IS_ERR(moxart_rtc->rtc)) { | |
284 | dev_err(&pdev->dev, "devm_rtc_device_register failed\n"); | |
285 | return PTR_ERR(moxart_rtc->rtc); | |
286 | } | |
287 | ||
288 | return 0; | |
289 | } | |
290 | ||
291 | static const struct of_device_id moxart_rtc_match[] = { | |
292 | { .compatible = "moxa,moxart-rtc" }, | |
293 | { }, | |
294 | }; | |
73798d5c | 295 | MODULE_DEVICE_TABLE(of, moxart_rtc_match); |
453b4c6d JJ |
296 | |
297 | static struct platform_driver moxart_rtc_driver = { | |
298 | .probe = moxart_rtc_probe, | |
299 | .driver = { | |
300 | .name = "moxart-rtc", | |
453b4c6d JJ |
301 | .of_match_table = moxart_rtc_match, |
302 | }, | |
303 | }; | |
304 | module_platform_driver(moxart_rtc_driver); | |
305 | ||
306 | MODULE_DESCRIPTION("MOXART RTC driver"); | |
307 | MODULE_LICENSE("GPL"); | |
308 | MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>"); |