rtc: add hym8563 rtc-driver
From: Heiko Stuebner <heiko@...> Date: Sat, 26 Oct 2013 01:29:21 +0200
Commit-Message
The Haoyu Microelectronics HYM8563 provides rtc- and alarm functions as well as a clock output of up to 32kHz. Signed-off-by: Heiko Stuebner <heiko@...>
Patch-Comment
drivers/rtc/Kconfig | 11 + drivers/rtc/Makefile | 1 + drivers/rtc/rtc-hym8563.c | 601 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 613 insertions(+) create mode 100644 drivers/rtc/rtc-hym8563.c
Statistics
- 613 lines added
- 0 lines removed
Changes
----------------------------- drivers/rtc/Kconfig ------------------------------
index 0077302..4bd489c 100644
@@ -212,6 +212,17 @@ config RTC_DRV_DS3232
This driver can also be built as a module. If so, the module
will be called rtc-ds3232.
+config RTC_DRV_HYM8563
+ tristate "Haoyu Microelectronics HYM8563"
+ depends on I2C && OF
+ help
+ Say Y to enable support for the HYM8563 I2C RTC chip. Apart
+ from the usual rtc functions it provides a clock output of
+ up to 32kHz.
+
+ This driver can also be built as a module. If so, the module
+ will be called rtc-hym8563.
+
config RTC_DRV_LP8788
tristate "TI LP8788 RTC driver"
depends on MFD_LP8788
----------------------------- drivers/rtc/Makefile -----------------------------
index 27b4bd8..913c5be 100644
@@ -55,6 +55,7 @@ obj-$(CONFIG_RTC_DRV_EP93XX) += rtc-ep93xx.o
obj-$(CONFIG_RTC_DRV_FM3130) += rtc-fm3130.o
obj-$(CONFIG_RTC_DRV_GENERIC) += rtc-generic.o
obj-$(CONFIG_RTC_DRV_HID_SENSOR_TIME) += rtc-hid-sensor-time.o
+obj-$(CONFIG_RTC_DRV_HYM8563) += rtc-hym8563.o
obj-$(CONFIG_RTC_DRV_IMXDI) += rtc-imxdi.o
obj-$(CONFIG_RTC_DRV_ISL1208) += rtc-isl1208.o
obj-$(CONFIG_RTC_DRV_ISL12022) += rtc-isl12022.o
-------------------------- drivers/rtc/rtc-hym8563.c ---------------------------
new file mode 100644
index 0000000..841392c
@@ -0,0 +1,601 @@
+/*
+ * Haoyu HYM8563 RTC driver
+ *
+ * Copyright (C) 2013 MundoReader S.L.
+ * Author: Heiko Stuebner <heiko@sntech.de>
+ *
+ * based on rtc-HYM8563
+ * Copyright (C) 2010 ROCKCHIP, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/clk-provider.h>
+#include <linux/i2c.h>
+#include <linux/bcd.h>
+#include <linux/rtc.h>
+
+#define HYM8563_CTL1 0x00
+#define HYM8563_CTL1_TEST BIT(7)
+#define HYM8563_CTL1_STOP BIT(5)
+#define HYM8563_CTL1_TESTC BIT(3)
+
+#define HYM8563_CTL2 0x01
+#define HYM8563_CTL2_TI_TP BIT(4)
+#define HYM8563_CTL2_AF BIT(3)
+#define HYM8563_CTL2_TF BIT(2)
+#define HYM8563_CTL2_AIE BIT(1)
+#define HYM8563_CTL2_TIE BIT(0)
+
+#define HYM8563_SEC 0x02
+#define HYM8563_SEC_VL BIT(7)
+#define HYM8563_SEC_MASK 0x7f
+
+#define HYM8563_MIN 0x03
+#define HYM8563_MIN_MASK 0x7f
+
+#define HYM8563_HOUR 0x04
+#define HYM8563_HOUR_MASK 0x3f
+
+#define HYM8563_DAY 0x05
+#define HYM8563_DAY_MASK 0x3f
+
+#define HYM8563_WEEKDAY 0x06
+#define HYM8563_WEEKDAY_MASK 0x07
+
+#define HYM8563_MONTH 0x07
+#define HYM8563_MONTH_CENTURY BIT(7)
+#define HYM8563_MONTH_MASK 0x1f
+
+#define HYM8563_YEAR 0x08
+
+#define HYM8563_ALM_MIN 0x09
+#define HYM8563_ALM_HOUR 0x0a
+#define HYM8563_ALM_DAY 0x0b
+#define HYM8563_ALM_WEEK 0x0c
+
+/* Each alarm check can be disabled by setting this bit in the register */
+#define HYM8563_ALM_BIT_DISABLE BIT(7)
+
+#define HYM8563_CLKOUT 0x0d
+#define HYM8563_CLKOUT_DISABLE BIT(7)
+#define HYM8563_CLKOUT_32768 0
+#define HYM8563_CLKOUT_1024 1
+#define HYM8563_CLKOUT_32 2
+#define HYM8563_CLKOUT_1 3
+#define HYM8563_CLKOUT_MASK 3
+
+#define HYM8563_TMR_CTL 0x0e
+#define HYM8563_TMR_CTL_ENABLE BIT(7)
+#define HYM8563_TMR_CTL_4096 0
+#define HYM8563_TMR_CTL_64 1
+#define HYM8563_TMR_CTL_1 2
+#define HYM8563_TMR_CTL_1_60 3
+#define HYM8563_TMR_CTL_MASK 3
+
+#define HYM8563_TMR_CNT 0x0f
+
+struct hym8563 {
+ struct i2c_client *client;
+ struct rtc_device *rtc;
+ bool valid;
+ struct clk_hw clkout_hw;
+};
+
+/*
+ * RTC handling
+ */
+
+static int hym8563_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct hym8563 *hym8563 = i2c_get_clientdata(client);
+ u8 buf[7];
+ int ret;
+
+ if (!hym8563->valid) {
+ dev_warn(&client->dev, "no valid clock/calendar values available\n");
+ return -EPERM;
+ }
+
+ ret = i2c_smbus_read_i2c_block_data(client, HYM8563_SEC, 7, buf);
+
+ tm->tm_sec = bcd2bin(buf[0] & HYM8563_SEC_MASK);
+ tm->tm_min = bcd2bin(buf[1] & HYM8563_MIN_MASK);
+ tm->tm_hour = bcd2bin(buf[2] & HYM8563_HOUR_MASK);
+ tm->tm_mday = bcd2bin(buf[3] & HYM8563_DAY_MASK);
+ tm->tm_wday = bcd2bin(buf[4] & HYM8563_WEEKDAY_MASK); /* 0 = Sun */
+ tm->tm_mon = bcd2bin(buf[5] & HYM8563_MONTH_MASK) - 1; /* 0 = Jan */
+ tm->tm_year = bcd2bin(buf[6]) + 100;
+
+ return 0;
+}
+
+static int hym8563_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct hym8563 *hym8563 = i2c_get_clientdata(client);
+ u8 buf[7];
+ int ret;
+
+ /* Years >= 2100 are to far in the future, 19XX is to early */
+ if (tm->tm_year < 100 || tm->tm_year >= 200)
+ return -EINVAL;
+
+ buf[0] = bin2bcd(tm->tm_sec);
+ buf[1] = bin2bcd(tm->tm_min);
+ buf[2] = bin2bcd(tm->tm_hour);
+ buf[3] = bin2bcd(tm->tm_mday);
+ buf[4] = bin2bcd(tm->tm_wday);
+ buf[5] = bin2bcd(tm->tm_mon + 1);
+
+ /*
+ * While the HYM8563 has a century flag in the month register,
+ * it does not seem to carry it over a subsequent write/read.
+ * So we'll limit ourself to 100 years, starting at 2000 for now.
+ */
+ buf[6] = tm->tm_year - 100;
+
+ /*
+ * CTL1 only contains TEST-mode bits apart from stop,
+ * so no need to read the value first
+ */
+ ret = i2c_smbus_write_byte_data(client, HYM8563_CTL1,
+ HYM8563_CTL1_STOP);
+ if (ret < 0)
+ return ret;
+
+ ret = i2c_smbus_write_i2c_block_data(client, HYM8563_SEC, 7, buf);
+ if (ret < 0)
+ return ret;
+
+ ret = i2c_smbus_write_byte_data(client, HYM8563_CTL1, 0);
+ if (ret < 0)
+ return ret;
+
+ hym8563->valid = true;
+
+ return 0;
+}
+
+static int hym8563_rtc_alarm_irq_enable(struct device *dev,
+ unsigned int enabled)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ int data;
+
+ data = i2c_smbus_read_byte_data(client, HYM8563_CTL2);
+ if (data < 0)
+ return data;
+
+ if (enabled)
+ data |= HYM8563_CTL2_AIE;
+ else
+ data &= ~HYM8563_CTL2_AIE;
+
+ return i2c_smbus_write_byte_data(client, HYM8563_CTL2, data);
+};
+
+static int hym8563_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct rtc_time *alm_tm = &alm->time;
+ u8 buf[4];
+ int ret;
+
+ ret = i2c_smbus_read_i2c_block_data(client, HYM8563_ALM_MIN, 4, buf);
+ if (ret < 0)
+ return ret;
+
+ /* The alarm only has a minute accuracy */
+ alm_tm->tm_sec = -1;
+
+ alm_tm->tm_min = (buf[0] & HYM8563_ALM_BIT_DISABLE) ?
+ -1 :
+ bcd2bin(buf[0] & HYM8563_MIN_MASK);
+ alm_tm->tm_hour = (buf[1] & HYM8563_ALM_BIT_DISABLE) ?
+ -1 :
+ bcd2bin(buf[1] & HYM8563_HOUR_MASK);
+ alm_tm->tm_mday = (buf[2] & HYM8563_ALM_BIT_DISABLE) ?
+ -1 :
+ bcd2bin(buf[2] & HYM8563_DAY_MASK);
+ alm_tm->tm_wday = (buf[3] & HYM8563_ALM_BIT_DISABLE) ?
+ -1 :
+ bcd2bin(buf[3] & HYM8563_WEEKDAY_MASK);
+
+ alm_tm->tm_mon = -1;
+ alm_tm->tm_year = -1;
+
+ ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2);
+ if (ret < 0)
+ return ret;
+
+ if (ret & HYM8563_CTL2_AIE)
+ alm->enabled = 1;
+
+ return 0;
+}
+
+static int hym8563_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct rtc_time *alm_tm = &alm->time;
+ u8 buf[4];
+ int ret;
+
+ /*
+ * The alarm has no seconds so deal with it
+ */
+ if (alm_tm->tm_sec) {
+ alm_tm->tm_sec = 0;
+ alm_tm->tm_min++;
+ if (alm_tm->tm_min >= 60) {
+ alm_tm->tm_min = 0;
+ alm_tm->tm_hour++;
+ if (alm_tm->tm_hour >= 24) {
+ alm_tm->tm_hour = 0;
+ alm_tm->tm_mday++;
+ if (alm_tm->tm_mday > 31)
+ alm_tm->tm_mday = 0;
+ }
+ }
+ }
+
+ ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2);
+ if (ret < 0)
+ return ret;
+
+ ret &= ~HYM8563_CTL2_AIE;
+
+ ret = i2c_smbus_write_byte_data(client, HYM8563_CTL2, ret);
+ if (ret < 0)
+ return ret;
+
+ buf[0] = (alm_tm->tm_min < 60 && alm_tm->tm_min >= 0) ?
+ bin2bcd(alm_tm->tm_min) : HYM8563_ALM_BIT_DISABLE;
+
+ buf[1] = (alm_tm->tm_hour < 24 && alm_tm->tm_hour >= 0) ?
+ bin2bcd(alm_tm->tm_hour) : HYM8563_ALM_BIT_DISABLE;
+
+ buf[2] = (alm_tm->tm_mday <= 31 && alm_tm->tm_mday >= 1) ?
+ bin2bcd(alm_tm->tm_mday) : HYM8563_ALM_BIT_DISABLE;
+
+ buf[3] = (alm_tm->tm_wday < 7 && alm_tm->tm_wday >= 0) ?
+ bin2bcd(alm_tm->tm_wday) : HYM8563_ALM_BIT_DISABLE;
+
+ ret = i2c_smbus_write_i2c_block_data(client, HYM8563_ALM_MIN, 4, buf);
+ if (ret < 0)
+ return ret;
+
+ return hym8563_rtc_alarm_irq_enable(dev, alm->enabled);
+}
+
+static const struct rtc_class_ops hym8563_rtc_ops = {
+ .read_time = hym8563_rtc_read_time,
+ .set_time = hym8563_rtc_set_time,
+ .alarm_irq_enable = hym8563_rtc_alarm_irq_enable,
+ .read_alarm = hym8563_rtc_read_alarm,
+ .set_alarm = hym8563_rtc_set_alarm,
+};
+
+/*
+ * Handling of the clkout
+ */
+
+#define clkout_hw_to_hym8563(_hw) container_of(_hw, struct hym8563, clkout_hw)
+
+static int clkout_rates[] = {
+ 32768,
+ 1024,
+ 32,
+ 1,
+};
+
+static unsigned long hym8563_clkout_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw);
+ struct i2c_client *client = hym8563->client;
+ int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT);
+
+ if (ret < 0 || ret & HYM8563_CLKOUT_DISABLE)
+ return 0;
+
+ ret &= HYM8563_CLKOUT_MASK;
+ return clkout_rates[ret];
+}
+
+static long hym8563_clkout_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)
+ if (clkout_rates[i] <= rate)
+ return clkout_rates[i];
+
+ return 0;
+}
+
+static int hym8563_clkout_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw);
+ struct i2c_client *client = hym8563->client;
+ int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT);
+ int i;
+
+ if (ret < 0)
+ return ret;
+
+ for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)
+ if (clkout_rates[i] == rate) {
+ ret &= ~HYM8563_CLKOUT_MASK;
+ ret |= i;
+ return i2c_smbus_write_byte_data(client,
+ HYM8563_CLKOUT, ret);
+ }
+
+ return -EINVAL;
+}
+
+static int hym8563_clkout_control(struct clk_hw *hw, bool enable)
+{
+ struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw);
+ struct i2c_client *client = hym8563->client;
+ int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT);
+
+ if (ret < 0)
+ return ret;
+
+ if (enable)
+ ret &= ~HYM8563_CLKOUT_DISABLE;
+ else
+ ret |= HYM8563_CLKOUT_DISABLE;
+
+ return i2c_smbus_write_byte_data(client, HYM8563_CLKOUT, ret);
+}
+
+static int hym8563_clkout_prepare(struct clk_hw *hw)
+{
+ return hym8563_clkout_control(hw, 1);
+}
+
+static void hym8563_clkout_unprepare(struct clk_hw *hw)
+{
+ hym8563_clkout_control(hw, 0);
+}
+
+static int hym8563_clkout_is_prepared(struct clk_hw *hw)
+{
+ struct hym8563 *hym8563 = clkout_hw_to_hym8563(hw);
+ struct i2c_client *client = hym8563->client;
+ int ret = i2c_smbus_read_byte_data(client, HYM8563_CLKOUT);
+
+ if (ret < 0)
+ return ret;
+
+ return !(ret & HYM8563_CLKOUT_DISABLE);
+}
+
+const struct clk_ops hym8563_clkout_ops = {
+ .prepare = hym8563_clkout_prepare,
+ .unprepare = hym8563_clkout_unprepare,
+ .is_prepared = hym8563_clkout_is_prepared,
+ .recalc_rate = hym8563_clkout_recalc_rate,
+ .round_rate = hym8563_clkout_round_rate,
+ .set_rate = hym8563_clkout_set_rate,
+};
+
+static struct clk *hym8563_clkout_register_clk(struct hym8563 *hym8563)
+{
+ struct i2c_client *client = hym8563->client;
+ struct device_node *node = client->dev.of_node;
+ struct clk *clk;
+ struct clk_init_data init;
+ int ret;
+
+ ret = i2c_smbus_write_byte_data(client, HYM8563_CLKOUT,
+ HYM8563_CLKOUT_DISABLE);
+ if (ret < 0)
+ return ERR_PTR(ret);
+
+ init.name = "hym8563-clkout";
+ init.ops = &hym8563_clkout_ops;
+ init.flags = CLK_IS_ROOT;
+ init.parent_names = NULL;
+ init.num_parents = 0;
+ hym8563->clkout_hw.init = &init;
+
+ /* register the clock */
+ clk = clk_register(&client->dev, &hym8563->clkout_hw);
+
+ if (!IS_ERR(clk))
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+
+ return clk;
+}
+
+/*
+ * The alarm interrupt is implemented as a level-low interrupt in the
+ * hym8563, while the timer interrupt uses a falling edge.
+ * We don't use the timer at all, so the interrupt is requested to
+ * use the level-low trigger.
+ */
+static irqreturn_t hym8563_irq(int irq, void *dev_id)
+{
+ struct hym8563 *hym8563 = (struct hym8563 *)dev_id;
+ struct i2c_client *client = hym8563->client;
+ struct mutex *lock = &hym8563->rtc->ops_lock;
+ int data, ret;
+
+ mutex_lock(lock);
+
+ /* Clear the alarm flag */
+
+ data = i2c_smbus_read_byte_data(client, HYM8563_CTL2);
+ if (data < 0) {
+ dev_err(&client->dev, "%s: error reading i2c data %d\n",
+ __func__, data);
+ goto out;
+ }
+
+ data &= ~HYM8563_CTL2_AF;
+
+ ret = i2c_smbus_write_byte_data(client, HYM8563_CTL2, data);
+ if (ret < 0) {
+ dev_err(&client->dev, "%s: error writing i2c data %d\n",
+ __func__, ret);
+ }
+
+out:
+ mutex_unlock(lock);
+ return IRQ_HANDLED;
+}
+
+static int hym8563_init_device(struct i2c_client *client)
+{
+ int ret;
+
+ /* Clear stop flag if present */
+ ret = i2c_smbus_write_byte_data(client, HYM8563_CTL1, 0);
+ if (ret < 0)
+ return ret;
+
+ ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2);
+ if (ret < 0)
+ return ret;
+
+ /* Disable alarm and timer interrupts */
+ ret &= ~HYM8563_CTL2_AIE;
+ ret &= ~HYM8563_CTL2_TIE;
+
+ /* Clear any pending alarm and timer flags */
+ if (ret & HYM8563_CTL2_AF)
+ ret &= ~HYM8563_CTL2_AF;
+
+ if (ret & HYM8563_CTL2_TF)
+ ret &= ~HYM8563_CTL2_TF;
+
+ ret &= ~HYM8563_CTL2_TI_TP;
+
+ return i2c_smbus_write_byte_data(client, HYM8563_CTL2, ret);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int hym8563_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ int ret;
+
+ if (device_may_wakeup(dev)) {
+ ret = enable_irq_wake(client->irq);
+ if (ret) {
+ dev_err(dev, "enable_irq_wake failed, %d\n", ret);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static int hym8563_resume(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+
+ if (device_may_wakeup(dev))
+ disable_irq_wake(client->irq);
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(hym8563_pm_ops, hym8563_suspend, hym8563_resume);
+
+static int hym8563_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct hym8563 *hym8563;
+ int ret;
+
+ hym8563 = devm_kzalloc(&client->dev, sizeof(*hym8563), GFP_KERNEL);
+ if (!hym8563)
+ return -ENOMEM;
+
+ hym8563->client = client;
+ i2c_set_clientdata(client, hym8563);
+
+ device_set_wakeup_capable(&client->dev, true);
+
+ ret = hym8563_init_device(client);
+ if (ret) {
+ dev_err(&client->dev, "could not init device, %d\n", ret);
+ return ret;
+ }
+
+ ret = devm_request_threaded_irq(&client->dev, client->irq,
+ NULL, hym8563_irq,
+ IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+ client->name, hym8563);
+ if (ret < 0) {
+ dev_err(&client->dev, "irq %d request failed, %d\n",
+ client->irq, ret);
+ return ret;
+ }
+
+ /* check state of calendar information */
+ ret = i2c_smbus_read_byte_data(client, HYM8563_SEC);
+ if (ret < 0)
+ return ret;
+
+ hym8563->valid = !(ret & HYM8563_SEC_VL);
+ dev_dbg(&client->dev, "rtc information is %s\n",
+ hym8563->valid ? "valid" : "invalid");
+
+ hym8563->rtc = devm_rtc_device_register(&client->dev, client->name,
+ &hym8563_rtc_ops, THIS_MODULE);
+ if (IS_ERR(hym8563->rtc))
+ return PTR_ERR(hym8563->rtc);
+
+ if (IS_ENABLED(CONFIG_COMMON_CLK))
+ hym8563_clkout_register_clk(hym8563);
+
+ return 0;
+}
+
+static const struct i2c_device_id hym8563_id[] = {
+ { "hym8563", 0 },
+ {},
+};
+MODULE_DEVICE_TABLE(i2c, hym8563_id);
+
+static struct of_device_id hym8563_dt_idtable[] = {
+ { .compatible = "haoyu,hym8563" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, hym8563_dt_idtable);
+
+static struct i2c_driver hym8563_driver = {
+ .driver = {
+ .name = "rtc-hym8563",
+ .owner = THIS_MODULE,
+ .pm = &hym8563_pm_ops,
+ .of_match_table = of_match_ptr(hym8563_dt_idtable),
+ },
+ .probe = hym8563_probe,
+ .id_table = hym8563_id,
+};
+
+module_i2c_driver(hym8563_driver);
+
+MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
+MODULE_DESCRIPTION("HYM8563 RTC driver");
+MODULE_LICENSE("GPL");