1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * rtc-rc5t583.c -- RICOH RC5T583 Real Time Clock |
4 | * |
5 | * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. |
6 | * Author: Venu Byravarasu <vbyravarasu@nvidia.com> |
7 | */ |
8 | |
9 | #include <linux/kernel.h> |
10 | #include <linux/errno.h> |
11 | #include <linux/init.h> |
12 | #include <linux/module.h> |
13 | #include <linux/types.h> |
14 | #include <linux/rtc.h> |
15 | #include <linux/bcd.h> |
16 | #include <linux/platform_device.h> |
17 | #include <linux/interrupt.h> |
18 | #include <linux/mfd/rc5t583.h> |
19 | |
20 | struct rc5t583_rtc { |
21 | struct rtc_device *rtc; |
22 | /* To store the list of enabled interrupts, during system suspend */ |
23 | u32 irqen; |
24 | }; |
25 | |
26 | /* Total number of RTC registers needed to set time*/ |
27 | #define NUM_TIME_REGS (RC5T583_RTC_YEAR - RC5T583_RTC_SEC + 1) |
28 | |
29 | /* Total number of RTC registers needed to set Y-Alarm*/ |
30 | #define NUM_YAL_REGS (RC5T583_RTC_AY_YEAR - RC5T583_RTC_AY_MIN + 1) |
31 | |
32 | /* Set Y-Alarm interrupt */ |
33 | #define SET_YAL BIT(5) |
34 | |
35 | /* Get Y-Alarm interrupt status*/ |
36 | #define GET_YAL_STATUS BIT(3) |
37 | |
38 | static int rc5t583_rtc_alarm_irq_enable(struct device *dev, unsigned enabled) |
39 | { |
40 | struct rc5t583 *rc5t583 = dev_get_drvdata(dev: dev->parent); |
41 | u8 val; |
42 | |
43 | /* Set Y-Alarm, based on 'enabled' */ |
44 | val = enabled ? SET_YAL : 0; |
45 | |
46 | return regmap_update_bits(map: rc5t583->regmap, RC5T583_RTC_CTL1, SET_YAL, |
47 | val); |
48 | } |
49 | |
50 | /* |
51 | * Gets current rc5t583 RTC time and date parameters. |
52 | * |
53 | * The RTC's time/alarm representation is not what gmtime(3) requires |
54 | * Linux to use: |
55 | * |
56 | * - Months are 1..12 vs Linux 0-11 |
57 | * - Years are 0..99 vs Linux 1900..N (we assume 21st century) |
58 | */ |
59 | static int rc5t583_rtc_read_time(struct device *dev, struct rtc_time *tm) |
60 | { |
61 | struct rc5t583 *rc5t583 = dev_get_drvdata(dev: dev->parent); |
62 | u8 rtc_data[NUM_TIME_REGS]; |
63 | int ret; |
64 | |
65 | ret = regmap_bulk_read(map: rc5t583->regmap, RC5T583_RTC_SEC, val: rtc_data, |
66 | NUM_TIME_REGS); |
67 | if (ret < 0) { |
68 | dev_err(dev, "RTC read time failed with err:%d\n" , ret); |
69 | return ret; |
70 | } |
71 | |
72 | tm->tm_sec = bcd2bin(rtc_data[0]); |
73 | tm->tm_min = bcd2bin(rtc_data[1]); |
74 | tm->tm_hour = bcd2bin(rtc_data[2]); |
75 | tm->tm_wday = bcd2bin(rtc_data[3]); |
76 | tm->tm_mday = bcd2bin(rtc_data[4]); |
77 | tm->tm_mon = bcd2bin(rtc_data[5]) - 1; |
78 | tm->tm_year = bcd2bin(rtc_data[6]) + 100; |
79 | |
80 | return ret; |
81 | } |
82 | |
83 | static int rc5t583_rtc_set_time(struct device *dev, struct rtc_time *tm) |
84 | { |
85 | struct rc5t583 *rc5t583 = dev_get_drvdata(dev: dev->parent); |
86 | unsigned char rtc_data[NUM_TIME_REGS]; |
87 | int ret; |
88 | |
89 | rtc_data[0] = bin2bcd(tm->tm_sec); |
90 | rtc_data[1] = bin2bcd(tm->tm_min); |
91 | rtc_data[2] = bin2bcd(tm->tm_hour); |
92 | rtc_data[3] = bin2bcd(tm->tm_wday); |
93 | rtc_data[4] = bin2bcd(tm->tm_mday); |
94 | rtc_data[5] = bin2bcd(tm->tm_mon + 1); |
95 | rtc_data[6] = bin2bcd(tm->tm_year - 100); |
96 | |
97 | ret = regmap_bulk_write(map: rc5t583->regmap, RC5T583_RTC_SEC, val: rtc_data, |
98 | NUM_TIME_REGS); |
99 | if (ret < 0) { |
100 | dev_err(dev, "RTC set time failed with error %d\n" , ret); |
101 | return ret; |
102 | } |
103 | |
104 | return ret; |
105 | } |
106 | |
107 | static int rc5t583_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) |
108 | { |
109 | struct rc5t583 *rc5t583 = dev_get_drvdata(dev: dev->parent); |
110 | unsigned char alarm_data[NUM_YAL_REGS]; |
111 | u32 interrupt_enable; |
112 | int ret; |
113 | |
114 | ret = regmap_bulk_read(map: rc5t583->regmap, RC5T583_RTC_AY_MIN, val: alarm_data, |
115 | NUM_YAL_REGS); |
116 | if (ret < 0) { |
117 | dev_err(dev, "rtc_read_alarm error %d\n" , ret); |
118 | return ret; |
119 | } |
120 | |
121 | alm->time.tm_sec = 0; |
122 | alm->time.tm_min = bcd2bin(alarm_data[0]); |
123 | alm->time.tm_hour = bcd2bin(alarm_data[1]); |
124 | alm->time.tm_mday = bcd2bin(alarm_data[2]); |
125 | alm->time.tm_mon = bcd2bin(alarm_data[3]) - 1; |
126 | alm->time.tm_year = bcd2bin(alarm_data[4]) + 100; |
127 | |
128 | ret = regmap_read(map: rc5t583->regmap, RC5T583_RTC_CTL1, val: &interrupt_enable); |
129 | if (ret < 0) |
130 | return ret; |
131 | |
132 | /* check if YALE is set */ |
133 | if (interrupt_enable & SET_YAL) |
134 | alm->enabled = 1; |
135 | |
136 | return ret; |
137 | } |
138 | |
139 | static int rc5t583_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) |
140 | { |
141 | struct rc5t583 *rc5t583 = dev_get_drvdata(dev: dev->parent); |
142 | unsigned char alarm_data[NUM_YAL_REGS]; |
143 | int ret; |
144 | |
145 | ret = rc5t583_rtc_alarm_irq_enable(dev, enabled: 0); |
146 | if (ret) |
147 | return ret; |
148 | |
149 | alarm_data[0] = bin2bcd(alm->time.tm_min); |
150 | alarm_data[1] = bin2bcd(alm->time.tm_hour); |
151 | alarm_data[2] = bin2bcd(alm->time.tm_mday); |
152 | alarm_data[3] = bin2bcd(alm->time.tm_mon + 1); |
153 | alarm_data[4] = bin2bcd(alm->time.tm_year - 100); |
154 | |
155 | ret = regmap_bulk_write(map: rc5t583->regmap, RC5T583_RTC_AY_MIN, val: alarm_data, |
156 | NUM_YAL_REGS); |
157 | if (ret) { |
158 | dev_err(dev, "rtc_set_alarm error %d\n" , ret); |
159 | return ret; |
160 | } |
161 | |
162 | if (alm->enabled) |
163 | ret = rc5t583_rtc_alarm_irq_enable(dev, enabled: 1); |
164 | |
165 | return ret; |
166 | } |
167 | |
168 | static irqreturn_t rc5t583_rtc_interrupt(int irq, void *rtc) |
169 | { |
170 | struct device *dev = rtc; |
171 | struct rc5t583 *rc5t583 = dev_get_drvdata(dev: dev->parent); |
172 | struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(dev); |
173 | unsigned long events = 0; |
174 | int ret; |
175 | u32 rtc_reg; |
176 | |
177 | ret = regmap_read(map: rc5t583->regmap, RC5T583_RTC_CTL2, val: &rtc_reg); |
178 | if (ret < 0) |
179 | return IRQ_NONE; |
180 | |
181 | if (rtc_reg & GET_YAL_STATUS) { |
182 | events = RTC_IRQF | RTC_AF; |
183 | /* clear pending Y-alarm interrupt bit */ |
184 | rtc_reg &= ~GET_YAL_STATUS; |
185 | } |
186 | |
187 | ret = regmap_write(map: rc5t583->regmap, RC5T583_RTC_CTL2, val: rtc_reg); |
188 | if (ret) |
189 | return IRQ_NONE; |
190 | |
191 | /* Notify RTC core on event */ |
192 | rtc_update_irq(rtc: rc5t583_rtc->rtc, num: 1, events); |
193 | |
194 | return IRQ_HANDLED; |
195 | } |
196 | |
197 | static const struct rtc_class_ops rc5t583_rtc_ops = { |
198 | .read_time = rc5t583_rtc_read_time, |
199 | .set_time = rc5t583_rtc_set_time, |
200 | .read_alarm = rc5t583_rtc_read_alarm, |
201 | .set_alarm = rc5t583_rtc_set_alarm, |
202 | .alarm_irq_enable = rc5t583_rtc_alarm_irq_enable, |
203 | }; |
204 | |
205 | static int rc5t583_rtc_probe(struct platform_device *pdev) |
206 | { |
207 | struct rc5t583 *rc5t583 = dev_get_drvdata(dev: pdev->dev.parent); |
208 | struct rc5t583_rtc *ricoh_rtc; |
209 | struct rc5t583_platform_data *pmic_plat_data; |
210 | int ret; |
211 | int irq; |
212 | |
213 | ricoh_rtc = devm_kzalloc(dev: &pdev->dev, size: sizeof(struct rc5t583_rtc), |
214 | GFP_KERNEL); |
215 | if (!ricoh_rtc) |
216 | return -ENOMEM; |
217 | |
218 | platform_set_drvdata(pdev, data: ricoh_rtc); |
219 | |
220 | /* Clear pending interrupts */ |
221 | ret = regmap_write(map: rc5t583->regmap, RC5T583_RTC_CTL2, val: 0); |
222 | if (ret < 0) |
223 | return ret; |
224 | |
225 | /* clear RTC Adjust register */ |
226 | ret = regmap_write(map: rc5t583->regmap, RC5T583_RTC_ADJ, val: 0); |
227 | if (ret < 0) { |
228 | dev_err(&pdev->dev, "unable to program rtc_adjust reg\n" ); |
229 | return -EBUSY; |
230 | } |
231 | |
232 | pmic_plat_data = dev_get_platdata(dev: rc5t583->dev); |
233 | irq = pmic_plat_data->irq_base; |
234 | if (irq <= 0) { |
235 | dev_warn(&pdev->dev, "Wake up is not possible as irq = %d\n" , |
236 | irq); |
237 | return ret; |
238 | } |
239 | |
240 | irq += RC5T583_IRQ_YALE; |
241 | ret = devm_request_threaded_irq(dev: &pdev->dev, irq, NULL, |
242 | thread_fn: rc5t583_rtc_interrupt, IRQF_TRIGGER_LOW, |
243 | devname: "rtc-rc5t583" , dev_id: &pdev->dev); |
244 | if (ret < 0) { |
245 | dev_err(&pdev->dev, "IRQ is not free.\n" ); |
246 | return ret; |
247 | } |
248 | device_init_wakeup(dev: &pdev->dev, enable: 1); |
249 | |
250 | ricoh_rtc->rtc = devm_rtc_device_register(dev: &pdev->dev, name: pdev->name, |
251 | ops: &rc5t583_rtc_ops, THIS_MODULE); |
252 | if (IS_ERR(ptr: ricoh_rtc->rtc)) { |
253 | ret = PTR_ERR(ptr: ricoh_rtc->rtc); |
254 | dev_err(&pdev->dev, "RTC device register: err %d\n" , ret); |
255 | return ret; |
256 | } |
257 | |
258 | return 0; |
259 | } |
260 | |
261 | /* |
262 | * Disable rc5t583 RTC interrupts. |
263 | * Sets status flag to free. |
264 | */ |
265 | static void rc5t583_rtc_remove(struct platform_device *pdev) |
266 | { |
267 | struct rc5t583_rtc *rc5t583_rtc = platform_get_drvdata(pdev); |
268 | |
269 | rc5t583_rtc_alarm_irq_enable(dev: &rc5t583_rtc->rtc->dev, enabled: 0); |
270 | } |
271 | |
272 | #ifdef CONFIG_PM_SLEEP |
273 | static int rc5t583_rtc_suspend(struct device *dev) |
274 | { |
275 | struct rc5t583 *rc5t583 = dev_get_drvdata(dev: dev->parent); |
276 | struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(dev); |
277 | int ret; |
278 | |
279 | /* Store current list of enabled interrupts*/ |
280 | ret = regmap_read(map: rc5t583->regmap, RC5T583_RTC_CTL1, |
281 | val: &rc5t583_rtc->irqen); |
282 | return ret; |
283 | } |
284 | |
285 | static int rc5t583_rtc_resume(struct device *dev) |
286 | { |
287 | struct rc5t583 *rc5t583 = dev_get_drvdata(dev: dev->parent); |
288 | struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(dev); |
289 | |
290 | /* Restore list of enabled interrupts before suspend */ |
291 | return regmap_write(map: rc5t583->regmap, RC5T583_RTC_CTL1, |
292 | val: rc5t583_rtc->irqen); |
293 | } |
294 | #endif |
295 | |
296 | static SIMPLE_DEV_PM_OPS(rc5t583_rtc_pm_ops, rc5t583_rtc_suspend, |
297 | rc5t583_rtc_resume); |
298 | |
299 | static struct platform_driver rc5t583_rtc_driver = { |
300 | .probe = rc5t583_rtc_probe, |
301 | .remove_new = rc5t583_rtc_remove, |
302 | .driver = { |
303 | .name = "rtc-rc5t583" , |
304 | .pm = &rc5t583_rtc_pm_ops, |
305 | }, |
306 | }; |
307 | |
308 | module_platform_driver(rc5t583_rtc_driver); |
309 | MODULE_ALIAS("platform:rtc-rc5t583" ); |
310 | MODULE_AUTHOR("Venu Byravarasu <vbyravarasu@nvidia.com>" ); |
311 | MODULE_LICENSE("GPL v2" ); |
312 | |