include/libchip/mcp7940m-rtc.h

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /**
0004  * @file
0005  *
0006  * @ingroup shared_tod_mcp7940m_rtc
0007  *
0008  * @brief This file provides the interfaces of @ref shared_tod_mcp7940m_rtc.
0009  */
0010
0011 /*
0012  * Copyright (C) 2023 embedded brains GmbH & Co. KG
0013  *
0014  * Redistribution and use in source and binary forms, with or without
0015  * modification, are permitted provided that the following conditions
0016  * are met:
0017  * 1. Redistributions of source code must retain the above copyright
0018  *    notice, this list of conditions and the following disclaimer.
0019  * 2. Redistributions in binary form must reproduce the above copyright
0020  *    notice, this list of conditions and the following disclaimer in the
0021  *    documentation and/or other materials provided with the distribution.
0022  *
0023  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0024  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0025  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0026  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0027  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0028  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0029  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0030  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0031  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0032  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0033  * POSSIBILITY OF SUCH DAMAGE.
0034  */
0035
0036 #ifndef LIBCHIP_MCP7940M_RTC_H
0037 #define LIBCHIP_MCP7940M_RTC_H
0038
0039 #include <libchip/i2c-rtc.h>
0040
0041 #ifdef __cplusplus
0042 extern "C" {
0043 #endif /* __cplusplus */
0044
0045 /**
0046  * @defgroup shared_tod_mcp7940m_rtc
0047  *
0048  * @ingroup shared_tod_i2c_rtc
0049  *
0050  * @brief RTC driver for the MCP7940M
0051  *
0052  * To use this driver, use the following initialization:
0053  *
0054  * Define a context for the RTC somewhere:
0055  *
0056  *   static struct mcp7940m_rtc rtc_ctx =
0057  *     MCP7940M_RTC_INITIALIZER("/dev/i2c-1", 0x6F, true);
0058  *
0059  * Then you can use the following for the RTC_Table:
0060  *
0061  *   MCP7940M_RTC_TBL_ENTRY("/dev/rtc", &rtc_ctx)
0062  *
0063  * @{
0064  */
0065
0066 struct mcp7940m_rtc {
0067   struct i2c_rtc_base base;
0068
0069   /** True if a crystal should be used. False if an oscillator is connected. */
0070   bool crystal;
0071 };
0072
0073 /** Hardware init. Used internally. */
0074 int mcp7940m_hw_init(struct i2c_rtc_base *base);
0075
0076 #define MCP7940M_RTC_INITIALIZER(i2c_path, i2c_address, has_crystal) { \
0077     .base = I2C_RTC_INITIALIZER( \
0078         i2c_path, \
0079         i2c_address, \
0080         0, \
0081         I2C_RTC_ORDER_sec_min_hour_wkday_day_month_year, \
0082         "mcp7940", \
0083         mcp7940m_hw_init), \
0084     .crystal = has_crystal, \
0085   }
0086
0087 #define MCP7940M_RTC_TBL_ENTRY(dev_name, mcp7940m_rtc_ctx) \
0088           I2C_RTC_TBL_ENTRY(dev_name, mcp7940m_rtc_ctx)
0089
0090 /** @} */
0091
0092 #ifdef __cplusplus
0093 }
0094 #endif /* __cplusplus */
0095
0096 #endif /* LIBCHIP_MCP7940M_RTC_H */