Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / rtc / rtc-em3027.c

diff --git a/kernel/drivers/rtc/rtc-em3027.c b/kernel/drivers/rtc/rtc-em3027.c
new file mode 100644 (file)
index 0000000..4f4930a
--- /dev/null
+++ b/kernel/drivers/rtc/rtc-em3027.c
@@ -0,0 +1,162 @@
+/*
+ * An rtc/i2c driver for the EM Microelectronic EM3027
+ * Copyright 2011 CompuLab, Ltd.
+ *
+ * Author: Mike Rapoport <mike@compulab.co.il>
+ *
+ * Based on rtc-ds1672.c by Alessandro Zummo <a.zummo@towertech.it>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/i2c.h>
+#include <linux/rtc.h>
+#include <linux/bcd.h>
+#include <linux/module.h>
+#include <linux/of.h>
+
+/* Registers */
+#define EM3027_REG_ON_OFF_CTRL 0x00
+#define EM3027_REG_IRQ_CTRL    0x01
+#define EM3027_REG_IRQ_FLAGS   0x02
+#define EM3027_REG_STATUS      0x03
+#define EM3027_REG_RST_CTRL    0x04
+
+#define EM3027_REG_WATCH_SEC   0x08
+#define EM3027_REG_WATCH_MIN   0x09
+#define EM3027_REG_WATCH_HOUR  0x0a
+#define EM3027_REG_WATCH_DATE  0x0b
+#define EM3027_REG_WATCH_DAY   0x0c
+#define EM3027_REG_WATCH_MON   0x0d
+#define EM3027_REG_WATCH_YEAR  0x0e
+
+#define EM3027_REG_ALARM_SEC   0x10
+#define EM3027_REG_ALARM_MIN   0x11
+#define EM3027_REG_ALARM_HOUR  0x12
+#define EM3027_REG_ALARM_DATE  0x13
+#define EM3027_REG_ALARM_DAY   0x14
+#define EM3027_REG_ALARM_MON   0x15
+#define EM3027_REG_ALARM_YEAR  0x16
+
+static struct i2c_driver em3027_driver;
+
+static int em3027_get_time(struct device *dev, struct rtc_time *tm)
+{
+       struct i2c_client *client = to_i2c_client(dev);
+
+       unsigned char addr = EM3027_REG_WATCH_SEC;
+       unsigned char buf[7];
+
+       struct i2c_msg msgs[] = {
+               {/* setup read addr */
+                       .addr = client->addr,
+                       .len = 1,
+                       .buf = &addr
+               },
+               {/* read time/date */
+                       .addr = client->addr,
+                       .flags = I2C_M_RD,
+                       .len = 7,
+                       .buf = buf
+               },
+       };
+
+       /* read time/date registers */
+       if ((i2c_transfer(client->adapter, &msgs[0], 2)) != 2) {
+               dev_err(&client->dev, "%s: read error\n", __func__);
+               return -EIO;
+       }
+
+       tm->tm_sec      = bcd2bin(buf[0]);
+       tm->tm_min      = bcd2bin(buf[1]);
+       tm->tm_hour     = bcd2bin(buf[2]);
+       tm->tm_mday     = bcd2bin(buf[3]);
+       tm->tm_wday     = bcd2bin(buf[4]);
+       tm->tm_mon      = bcd2bin(buf[5]);
+       tm->tm_year     = bcd2bin(buf[6]) + 100;
+
+       return 0;
+}
+
+static int em3027_set_time(struct device *dev, struct rtc_time *tm)
+{
+       struct i2c_client *client = to_i2c_client(dev);
+       unsigned char buf[8];
+
+       struct i2c_msg msg = {
+               .addr = client->addr,
+               .len = 8,
+               .buf = buf,     /* write time/date */
+       };
+
+       buf[0] = EM3027_REG_WATCH_SEC;
+       buf[1] = bin2bcd(tm->tm_sec);
+       buf[2] = bin2bcd(tm->tm_min);
+       buf[3] = bin2bcd(tm->tm_hour);
+       buf[4] = bin2bcd(tm->tm_mday);
+       buf[5] = bin2bcd(tm->tm_wday);
+       buf[6] = bin2bcd(tm->tm_mon);
+       buf[7] = bin2bcd(tm->tm_year % 100);
+
+       /* write time/date registers */
+       if ((i2c_transfer(client->adapter, &msg, 1)) != 1) {
+               dev_err(&client->dev, "%s: write error\n", __func__);
+               return -EIO;
+       }
+
+       return 0;
+}
+
+static const struct rtc_class_ops em3027_rtc_ops = {
+       .read_time = em3027_get_time,
+       .set_time = em3027_set_time,
+};
+
+static int em3027_probe(struct i2c_client *client,
+                       const struct i2c_device_id *id)
+{
+       struct rtc_device *rtc;
+
+       if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
+               return -ENODEV;
+
+       rtc = devm_rtc_device_register(&client->dev, em3027_driver.driver.name,
+                                 &em3027_rtc_ops, THIS_MODULE);
+       if (IS_ERR(rtc))
+               return PTR_ERR(rtc);
+
+       i2c_set_clientdata(client, rtc);
+
+       return 0;
+}
+
+static struct i2c_device_id em3027_id[] = {
+       { "em3027", 0 },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, em3027_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id em3027_of_match[] = {
+       { .compatible = "emmicro,em3027", },
+       {}
+};
+MODULE_DEVICE_TABLE(of, em3027_of_match);
+#endif
+
+static struct i2c_driver em3027_driver = {
+       .driver = {
+                  .name = "rtc-em3027",
+                  .of_match_table = of_match_ptr(em3027_of_match),
+       },
+       .probe = &em3027_probe,
+       .id_table = em3027_id,
+};
+
+module_i2c_driver(em3027_driver);
+
+MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>");
+MODULE_DESCRIPTION("EM Microelectronic EM3027 RTC driver");
+MODULE_LICENSE("GPL");