@@ -980,6 +980,13 @@ config RTC_DRV_AB8500
Select this to enable the ST-Ericsson AB8500 power management IC RTC
support. This chip contains a battery- and capacitor-backed RTC.
+config RTC_DRV_ABX805
+ tristate "Abracon AB X805 RTC"
+ help
+ Select this to enable support for the Abracon AB X805 RTC.
+ AB X805 is the i2c flavour of the AB 18X5 family of ultra-low-power
+ battery- and capacitor-backed RTC..
+
config RTC_DRV_NUC900
tristate "NUC910/NUC920 RTC driver"
depends on ARCH_W90X900
@@ -24,6 +24,7 @@ obj-$(CONFIG_RTC_DRV_88PM860X) += rtc-88pm860x.o
obj-$(CONFIG_RTC_DRV_88PM80X) += rtc-88pm80x.o
obj-$(CONFIG_RTC_DRV_AB3100) += rtc-ab3100.o
obj-$(CONFIG_RTC_DRV_AB8500) += rtc-ab8500.o
+obj-$(CONFIG_RTC_DRV_ABX805) += rtc-abx805.o
obj-$(CONFIG_RTC_DRV_AS3722) += rtc-as3722.o
obj-$(CONFIG_RTC_DRV_AT32AP700X)+= rtc-at32ap700x.o
obj-$(CONFIG_RTC_DRV_AT91RM9200)+= rtc-at91rm9200.o
new file mode 100644
@@ -0,0 +1,223 @@
+/*
+ * A driver for the I2C members of the Abracon AB 18X5 RTC family,
+ * and compatible: AB 1805 and AB 0805
+ *
+ * Copyright 2014-2015 Macq S.A.
+ *
+ * Author: Philippe De Muyter <phdm@macqel.be>
+ *
+ * Based on rtc-em3027.c by Mike Rapoport <mike@compulab.co.il>
+ *
+ * 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>
+
+/* Registers */
+
+#define ABX805_REG_SECONDS 0x01
+#define ABX805_REG_CONFIGURATION_KEY 0x1f
+#define KEY_ENABLE_MISC_REGISTERS_WRITE_ACCESS 0x90
+#define ABX805_REG_TRICKLE 0x20
+#define TRICKLE_CHARGE_ENABLE 0xA0
+#define TRICKLE_STANDARD_DIODE 0x8
+#define TRICKLE_SCHOTTKY_DIODE 0x4
+#define TRICKLE_OUTPUT_RESISTOR_3KOHM 0x1
+#define TRICKLE_OUTPUT_RESISTOR_6KOHM 0x2
+#define TRICKLE_OUTPUT_RESISTOR_11KOHM 0x3
+#define ABX805_REG_ID0 0x28
+
+static struct i2c_driver abx805_driver;
+
+static int abx805_read_multiple_regs(struct i2c_client *client,
+ u8 *buf, u8 addr0, int len)
+{
+ u8 addr = addr0;
+ struct i2c_msg msgs[] = {
+ {/* setup read addr */
+ .addr = client->addr,
+ .len = 1,
+ .buf = &addr
+ },
+ {/* read into buf */
+ .addr = client->addr,
+ .flags = I2C_M_RD,
+ .len = len,
+ .buf = buf
+ },
+ };
+
+ if ((i2c_transfer(client->adapter, &msgs[0], 2)) != 2) {
+ dev_err(&client->dev, "%s: read error\n", __func__);
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int abx805_enable_trickle_charger(struct i2c_client *client)
+{
+ u8 buf[2];
+ struct i2c_msg msg = {
+ .addr = client->addr,
+ .len = 2,
+ .buf = buf,
+ };
+
+ /*
+ * Write 0x90 in the configuration key register (0x1F) to enable
+ * the access to the Trickle register
+ */
+ buf[0] = ABX805_REG_CONFIGURATION_KEY;
+ buf[1] = 0x9D;
+
+ /* write register */
+ if ((i2c_transfer(client->adapter, &msg, 1)) != 1) {
+ dev_err(&client->dev, "%s: write error\n", __func__);
+ return -EIO;
+ }
+
+ buf[0] = ABX805_REG_TRICKLE;
+ buf[1] = TRICKLE_CHARGE_ENABLE | TRICKLE_SCHOTTKY_DIODE |
+ TRICKLE_OUTPUT_RESISTOR_3KOHM;
+
+ /* write register */
+ if ((i2c_transfer(client->adapter, &msg, 1)) != 1) {
+ dev_err(&client->dev, "%s: write error\n", __func__);
+ return -EIO;
+ }
+ return 0;
+}
+
+static int abx805_get_time(struct device *dev, struct rtc_time *tm)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ u8 buf[7];
+ int err;
+
+ dev_dbg(dev, "abx805_get_time\n");
+ /* read time/date registers */
+ err = abx805_read_multiple_regs(client, buf, ABX805_REG_SECONDS,
+ sizeof(buf));
+ if (err) {
+ dev_err(&client->dev, "%s: read error\n", __func__);
+ return err;
+ }
+
+ 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_mon = bcd2bin(buf[4]) - 1;
+ tm->tm_year = bcd2bin(buf[5]) + 100;
+ tm->tm_wday = bcd2bin(buf[6]);
+
+ return 0;
+}
+
+static int abx805_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ u8 buf[8];
+
+ struct i2c_msg msg = {
+ .addr = client->addr,
+ .len = 8,
+ .buf = buf, /* write time/date */
+ };
+
+ dev_dbg(dev, "abx805_set_time\n");
+ buf[0] = ABX805_REG_SECONDS;
+ 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_mon + 1);
+ buf[6] = bin2bcd(tm->tm_year % 100);
+ buf[7] = bin2bcd(tm->tm_wday);
+
+ /* 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 abx805_rtc_ops = {
+ .read_time = abx805_get_time,
+ .set_time = abx805_set_time,
+};
+
+static int abx805_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ int err;
+ struct rtc_device *rtc;
+ char buf[7];
+ unsigned int partnumber;
+ unsigned int majrev, minrev;
+ unsigned int lot;
+ unsigned int wafer;
+ unsigned int uid;
+
+ dev_info(&client->dev, "abx805_probe\n");
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
+ return -ENODEV;
+
+ err = abx805_read_multiple_regs(client, buf, ABX805_REG_ID0,
+ sizeof(buf));
+ if (err)
+ return err;
+
+ partnumber = (buf[0] << 8) | buf[1];
+ majrev = buf[2] >> 3;
+ minrev = buf[2] & 0x7;
+ lot = ((buf[4] & 0x80) << 2) | ((buf[6] & 0x80) << 1) | buf[3];
+ uid = ((buf[4] & 0x7f) << 8) | buf[5];
+ wafer = (buf[6] & 0x7c) >> 2;
+ dev_info(&client->dev, "model %04x, revision %u.%u, lot %x, wafer %x, uid %x\n",
+ partnumber, majrev, minrev, lot, wafer, uid);
+
+ abx805_enable_trickle_charger(client);
+
+ rtc = devm_rtc_device_register(&client->dev, abx805_driver.driver.name,
+ &abx805_rtc_ops, THIS_MODULE);
+ if (IS_ERR(rtc))
+ return PTR_ERR(rtc);
+
+ i2c_set_clientdata(client, rtc);
+
+ return 0;
+}
+
+static int abx805_remove(struct i2c_client *client)
+{
+ return 0;
+}
+
+static struct i2c_device_id abx805_id[] = {
+ { "abx805-rtc", 0 },
+ { }
+};
+
+static struct i2c_driver abx805_driver = {
+ .driver = {
+ .name = "abx805-rtc",
+ },
+ .probe = &abx805_probe,
+ .remove = &abx805_remove,
+ .id_table = abx805_id,
+};
+
+module_i2c_driver(abx805_driver);
+
+MODULE_AUTHOR("Philippe De Muyter <phdm@macqel.be>");
+MODULE_DESCRIPTION("Abracon AB X805 RTC driver");
+MODULE_LICENSE("GPL");