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path: root/drivers/rtc/rtc-ac100.c
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Diffstat (limited to 'drivers/rtc/rtc-ac100.c')
-rw-r--r--drivers/rtc/rtc-ac100.c627
1 files changed, 627 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-ac100.c b/drivers/rtc/rtc-ac100.c
new file mode 100644
index 000000000000..70b4fd0f6122
--- /dev/null
+++ b/drivers/rtc/rtc-ac100.c
@@ -0,0 +1,627 @@
+/*
+ * RTC Driver for X-Powers AC100
+ *
+ * Copyright (c) 2016 Chen-Yu Tsai
+ *
+ * Chen-Yu Tsai <wens@csie.org>
+ *
+ * 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.
+ *
+ * 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/bcd.h>
+#include <linux/clk-provider.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mfd/ac100.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/rtc.h>
+#include <linux/types.h>
+
+/* Control register */
+#define AC100_RTC_CTRL_24HOUR BIT(0)
+
+/* Clock output register bits */
+#define AC100_CLKOUT_PRE_DIV_SHIFT 5
+#define AC100_CLKOUT_PRE_DIV_WIDTH 3
+#define AC100_CLKOUT_MUX_SHIFT 4
+#define AC100_CLKOUT_MUX_WIDTH 1
+#define AC100_CLKOUT_DIV_SHIFT 1
+#define AC100_CLKOUT_DIV_WIDTH 3
+#define AC100_CLKOUT_EN BIT(0)
+
+/* RTC */
+#define AC100_RTC_SEC_MASK GENMASK(6, 0)
+#define AC100_RTC_MIN_MASK GENMASK(6, 0)
+#define AC100_RTC_HOU_MASK GENMASK(5, 0)
+#define AC100_RTC_WEE_MASK GENMASK(2, 0)
+#define AC100_RTC_DAY_MASK GENMASK(5, 0)
+#define AC100_RTC_MON_MASK GENMASK(4, 0)
+#define AC100_RTC_YEA_MASK GENMASK(7, 0)
+#define AC100_RTC_YEA_LEAP BIT(15)
+#define AC100_RTC_UPD_TRIGGER BIT(15)
+
+/* Alarm (wall clock) */
+#define AC100_ALM_INT_ENABLE BIT(0)
+
+#define AC100_ALM_SEC_MASK GENMASK(6, 0)
+#define AC100_ALM_MIN_MASK GENMASK(6, 0)
+#define AC100_ALM_HOU_MASK GENMASK(5, 0)
+#define AC100_ALM_WEE_MASK GENMASK(2, 0)
+#define AC100_ALM_DAY_MASK GENMASK(5, 0)
+#define AC100_ALM_MON_MASK GENMASK(4, 0)
+#define AC100_ALM_YEA_MASK GENMASK(7, 0)
+#define AC100_ALM_ENABLE_FLAG BIT(15)
+#define AC100_ALM_UPD_TRIGGER BIT(15)
+
+/*
+ * The year parameter passed to the driver is usually an offset relative to
+ * the year 1900. This macro is used to convert this offset to another one
+ * relative to the minimum year allowed by the hardware.
+ *
+ * The year range is 1970 - 2069. This range is selected to match Allwinner's
+ * driver.
+ */
+#define AC100_YEAR_MIN 1970
+#define AC100_YEAR_MAX 2069
+#define AC100_YEAR_OFF (AC100_YEAR_MIN - 1900)
+
+struct ac100_clkout {
+ struct clk_hw hw;
+ struct regmap *regmap;
+ u8 offset;
+};
+
+#define to_ac100_clkout(_hw) container_of(_hw, struct ac100_clkout, hw)
+
+#define AC100_RTC_32K_NAME "ac100-rtc-32k"
+#define AC100_RTC_32K_RATE 32768
+#define AC100_CLKOUT_NUM 3
+
+static const char * const ac100_clkout_names[AC100_CLKOUT_NUM] = {
+ "ac100-cko1-rtc",
+ "ac100-cko2-rtc",
+ "ac100-cko3-rtc",
+};
+
+struct ac100_rtc_dev {
+ struct rtc_device *rtc;
+ struct device *dev;
+ struct regmap *regmap;
+ int irq;
+ unsigned long alarm;
+
+ struct clk_hw *rtc_32k_clk;
+ struct ac100_clkout clks[AC100_CLKOUT_NUM];
+ struct clk_hw_onecell_data *clk_data;
+};
+
+/**
+ * Clock controls for 3 clock output pins
+ */
+
+static const struct clk_div_table ac100_clkout_prediv[] = {
+ { .val = 0, .div = 1 },
+ { .val = 1, .div = 2 },
+ { .val = 2, .div = 4 },
+ { .val = 3, .div = 8 },
+ { .val = 4, .div = 16 },
+ { .val = 5, .div = 32 },
+ { .val = 6, .div = 64 },
+ { .val = 7, .div = 122 },
+ { },
+};
+
+/* Abuse the fact that one parent is 32768 Hz, and the other is 4 MHz */
+static unsigned long ac100_clkout_recalc_rate(struct clk_hw *hw,
+ unsigned long prate)
+{
+ struct ac100_clkout *clk = to_ac100_clkout(hw);
+ unsigned int reg, div;
+
+ regmap_read(clk->regmap, clk->offset, &reg);
+
+ /* Handle pre-divider first */
+ if (prate != AC100_RTC_32K_RATE) {
+ div = (reg >> AC100_CLKOUT_PRE_DIV_SHIFT) &
+ ((1 << AC100_CLKOUT_PRE_DIV_WIDTH) - 1);
+ prate = divider_recalc_rate(hw, prate, div,
+ ac100_clkout_prediv, 0);
+ }
+
+ div = (reg >> AC100_CLKOUT_DIV_SHIFT) &
+ (BIT(AC100_CLKOUT_DIV_WIDTH) - 1);
+ return divider_recalc_rate(hw, prate, div, NULL,
+ CLK_DIVIDER_POWER_OF_TWO);
+}
+
+static long ac100_clkout_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long prate)
+{
+ unsigned long best_rate = 0, tmp_rate, tmp_prate;
+ int i;
+
+ if (prate == AC100_RTC_32K_RATE)
+ return divider_round_rate(hw, rate, &prate, NULL,
+ AC100_CLKOUT_DIV_WIDTH,
+ CLK_DIVIDER_POWER_OF_TWO);
+
+ for (i = 0; ac100_clkout_prediv[i].div; i++) {
+ tmp_prate = DIV_ROUND_UP(prate, ac100_clkout_prediv[i].val);
+ tmp_rate = divider_round_rate(hw, rate, &tmp_prate, NULL,
+ AC100_CLKOUT_DIV_WIDTH,
+ CLK_DIVIDER_POWER_OF_TWO);
+
+ if (tmp_rate > rate)
+ continue;
+ if (rate - tmp_rate < best_rate - tmp_rate)
+ best_rate = tmp_rate;
+ }
+
+ return best_rate;
+}
+
+static int ac100_clkout_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ struct clk_hw *best_parent;
+ unsigned long best = 0;
+ int i, num_parents = clk_hw_get_num_parents(hw);
+
+ for (i = 0; i < num_parents; i++) {
+ struct clk_hw *parent = clk_hw_get_parent_by_index(hw, i);
+ unsigned long tmp, prate = clk_hw_get_rate(parent);
+
+ tmp = ac100_clkout_round_rate(hw, req->rate, prate);
+
+ if (tmp > req->rate)
+ continue;
+ if (req->rate - tmp < req->rate - best) {
+ best = tmp;
+ best_parent = parent;
+ }
+ }
+
+ if (!best)
+ return -EINVAL;
+
+ req->best_parent_hw = best_parent;
+ req->best_parent_rate = best;
+ req->rate = best;
+
+ return 0;
+}
+
+static int ac100_clkout_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long prate)
+{
+ struct ac100_clkout *clk = to_ac100_clkout(hw);
+ int div = 0, pre_div = 0;
+
+ do {
+ div = divider_get_val(rate * ac100_clkout_prediv[pre_div].div,
+ prate, NULL, AC100_CLKOUT_DIV_WIDTH,
+ CLK_DIVIDER_POWER_OF_TWO);
+ if (div >= 0)
+ break;
+ } while (prate != AC100_RTC_32K_RATE &&
+ ac100_clkout_prediv[++pre_div].div);
+
+ if (div < 0)
+ return div;
+
+ pre_div = ac100_clkout_prediv[pre_div].val;
+
+ regmap_update_bits(clk->regmap, clk->offset,
+ ((1 << AC100_CLKOUT_DIV_WIDTH) - 1) << AC100_CLKOUT_DIV_SHIFT |
+ ((1 << AC100_CLKOUT_PRE_DIV_WIDTH) - 1) << AC100_CLKOUT_PRE_DIV_SHIFT,
+ (div - 1) << AC100_CLKOUT_DIV_SHIFT |
+ (pre_div - 1) << AC100_CLKOUT_PRE_DIV_SHIFT);
+
+ return 0;
+}
+
+static int ac100_clkout_prepare(struct clk_hw *hw)
+{
+ struct ac100_clkout *clk = to_ac100_clkout(hw);
+
+ return regmap_update_bits(clk->regmap, clk->offset, AC100_CLKOUT_EN,
+ AC100_CLKOUT_EN);
+}
+
+static void ac100_clkout_unprepare(struct clk_hw *hw)
+{
+ struct ac100_clkout *clk = to_ac100_clkout(hw);
+
+ regmap_update_bits(clk->regmap, clk->offset, AC100_CLKOUT_EN, 0);
+}
+
+static int ac100_clkout_is_prepared(struct clk_hw *hw)
+{
+ struct ac100_clkout *clk = to_ac100_clkout(hw);
+ unsigned int reg;
+
+ regmap_read(clk->regmap, clk->offset, &reg);
+
+ return reg & AC100_CLKOUT_EN;
+}
+
+static u8 ac100_clkout_get_parent(struct clk_hw *hw)
+{
+ struct ac100_clkout *clk = to_ac100_clkout(hw);
+ unsigned int reg;
+
+ regmap_read(clk->regmap, clk->offset, &reg);
+
+ return (reg >> AC100_CLKOUT_MUX_SHIFT) & 0x1;
+}
+
+static int ac100_clkout_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct ac100_clkout *clk = to_ac100_clkout(hw);
+
+ return regmap_update_bits(clk->regmap, clk->offset,
+ BIT(AC100_CLKOUT_MUX_SHIFT),
+ index ? BIT(AC100_CLKOUT_MUX_SHIFT) : 0);
+}
+
+static const struct clk_ops ac100_clkout_ops = {
+ .prepare = ac100_clkout_prepare,
+ .unprepare = ac100_clkout_unprepare,
+ .is_prepared = ac100_clkout_is_prepared,
+ .recalc_rate = ac100_clkout_recalc_rate,
+ .determine_rate = ac100_clkout_determine_rate,
+ .get_parent = ac100_clkout_get_parent,
+ .set_parent = ac100_clkout_set_parent,
+ .set_rate = ac100_clkout_set_rate,
+};
+
+static int ac100_rtc_register_clks(struct ac100_rtc_dev *chip)
+{
+ struct device_node *np = chip->dev->of_node;
+ const char *parents[2] = {AC100_RTC_32K_NAME};
+ int i, ret;
+
+ chip->clk_data = devm_kzalloc(chip->dev, sizeof(*chip->clk_data) +
+ sizeof(*chip->clk_data->hws) *
+ AC100_CLKOUT_NUM,
+ GFP_KERNEL);
+ if (!chip->clk_data)
+ return -ENOMEM;
+
+ chip->rtc_32k_clk = clk_hw_register_fixed_rate(chip->dev,
+ AC100_RTC_32K_NAME,
+ NULL, 0,
+ AC100_RTC_32K_RATE);
+ if (IS_ERR(chip->rtc_32k_clk)) {
+ ret = PTR_ERR(chip->rtc_32k_clk);
+ dev_err(chip->dev, "Failed to register RTC-32k clock: %d\n",
+ ret);
+ return ret;
+ }
+
+ parents[1] = of_clk_get_parent_name(np, 0);
+ if (!parents[1]) {
+ dev_err(chip->dev, "Failed to get ADDA 4M clock\n");
+ return -EINVAL;
+ }
+
+ for (i = 0; i < AC100_CLKOUT_NUM; i++) {
+ struct ac100_clkout *clk = &chip->clks[i];
+ struct clk_init_data init = {
+ .name = ac100_clkout_names[i],
+ .ops = &ac100_clkout_ops,
+ .parent_names = parents,
+ .num_parents = ARRAY_SIZE(parents),
+ .flags = 0,
+ };
+
+ clk->regmap = chip->regmap;
+ clk->offset = AC100_CLKOUT_CTRL1 + i;
+ clk->hw.init = &init;
+
+ ret = devm_clk_hw_register(chip->dev, &clk->hw);
+ if (ret) {
+ dev_err(chip->dev, "Failed to register clk '%s': %d\n",
+ init.name, ret);
+ goto err_unregister_rtc_32k;
+ }
+
+ chip->clk_data->hws[i] = &clk->hw;
+ }
+
+ chip->clk_data->num = i;
+ ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, chip->clk_data);
+ if (ret)
+ goto err_unregister_rtc_32k;
+
+ return 0;
+
+err_unregister_rtc_32k:
+ clk_unregister_fixed_rate(chip->rtc_32k_clk->clk);
+
+ return ret;
+}
+
+static void ac100_rtc_unregister_clks(struct ac100_rtc_dev *chip)
+{
+ of_clk_del_provider(chip->dev->of_node);
+ clk_unregister_fixed_rate(chip->rtc_32k_clk->clk);
+}
+
+/**
+ * RTC related bits
+ */
+static int ac100_rtc_get_time(struct device *dev, struct rtc_time *rtc_tm)
+{
+ struct ac100_rtc_dev *chip = dev_get_drvdata(dev);
+ struct regmap *regmap = chip->regmap;
+ u16 reg[7];
+ int ret;
+
+ ret = regmap_bulk_read(regmap, AC100_RTC_SEC, reg, 7);
+ if (ret)
+ return ret;
+
+ rtc_tm->tm_sec = bcd2bin(reg[0] & AC100_RTC_SEC_MASK);
+ rtc_tm->tm_min = bcd2bin(reg[1] & AC100_RTC_MIN_MASK);
+ rtc_tm->tm_hour = bcd2bin(reg[2] & AC100_RTC_HOU_MASK);
+ rtc_tm->tm_wday = bcd2bin(reg[3] & AC100_RTC_WEE_MASK);
+ rtc_tm->tm_mday = bcd2bin(reg[4] & AC100_RTC_DAY_MASK);
+ rtc_tm->tm_mon = bcd2bin(reg[5] & AC100_RTC_MON_MASK) - 1;
+ rtc_tm->tm_year = bcd2bin(reg[6] & AC100_RTC_YEA_MASK) +
+ AC100_YEAR_OFF;
+
+ return rtc_valid_tm(rtc_tm);
+}
+
+static int ac100_rtc_set_time(struct device *dev, struct rtc_time *rtc_tm)
+{
+ struct ac100_rtc_dev *chip = dev_get_drvdata(dev);
+ struct regmap *regmap = chip->regmap;
+ int year;
+ u16 reg[8];
+
+ /* our RTC has a limited year range... */
+ year = rtc_tm->tm_year - AC100_YEAR_OFF;
+ if (year < 0 || year > (AC100_YEAR_MAX - 1900)) {
+ dev_err(dev, "rtc only supports year in range %d - %d\n",
+ AC100_YEAR_MIN, AC100_YEAR_MAX);
+ return -EINVAL;
+ }
+
+ /* convert to BCD */
+ reg[0] = bin2bcd(rtc_tm->tm_sec) & AC100_RTC_SEC_MASK;
+ reg[1] = bin2bcd(rtc_tm->tm_min) & AC100_RTC_MIN_MASK;
+ reg[2] = bin2bcd(rtc_tm->tm_hour) & AC100_RTC_HOU_MASK;
+ reg[3] = bin2bcd(rtc_tm->tm_wday) & AC100_RTC_WEE_MASK;
+ reg[4] = bin2bcd(rtc_tm->tm_mday) & AC100_RTC_DAY_MASK;
+ reg[5] = bin2bcd(rtc_tm->tm_mon + 1) & AC100_RTC_MON_MASK;
+ reg[6] = bin2bcd(year) & AC100_RTC_YEA_MASK;
+ /* trigger write */
+ reg[7] = AC100_RTC_UPD_TRIGGER;
+
+ /* Is it a leap year? */
+ if (is_leap_year(year + AC100_YEAR_OFF + 1900))
+ reg[6] |= AC100_RTC_YEA_LEAP;
+
+ return regmap_bulk_write(regmap, AC100_RTC_SEC, reg, 8);
+}
+
+static int ac100_rtc_alarm_irq_enable(struct device *dev, unsigned int en)
+{
+ struct ac100_rtc_dev *chip = dev_get_drvdata(dev);
+ struct regmap *regmap = chip->regmap;
+ unsigned int val;
+
+ val = en ? AC100_ALM_INT_ENABLE : 0;
+
+ return regmap_write(regmap, AC100_ALM_INT_ENA, val);
+}
+
+static int ac100_rtc_get_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct ac100_rtc_dev *chip = dev_get_drvdata(dev);
+ struct regmap *regmap = chip->regmap;
+ struct rtc_time *alrm_tm = &alrm->time;
+ u16 reg[7];
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(regmap, AC100_ALM_INT_ENA, &val);
+ if (ret)
+ return ret;
+
+ alrm->enabled = !!(val & AC100_ALM_INT_ENABLE);
+
+ ret = regmap_bulk_read(regmap, AC100_ALM_SEC, reg, 7);
+ if (ret)
+ return ret;
+
+ alrm_tm->tm_sec = bcd2bin(reg[0] & AC100_ALM_SEC_MASK);
+ alrm_tm->tm_min = bcd2bin(reg[1] & AC100_ALM_MIN_MASK);
+ alrm_tm->tm_hour = bcd2bin(reg[2] & AC100_ALM_HOU_MASK);
+ alrm_tm->tm_wday = bcd2bin(reg[3] & AC100_ALM_WEE_MASK);
+ alrm_tm->tm_mday = bcd2bin(reg[4] & AC100_ALM_DAY_MASK);
+ alrm_tm->tm_mon = bcd2bin(reg[5] & AC100_ALM_MON_MASK) - 1;
+ alrm_tm->tm_year = bcd2bin(reg[6] & AC100_ALM_YEA_MASK) +
+ AC100_YEAR_OFF;
+
+ return 0;
+}
+
+static int ac100_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct ac100_rtc_dev *chip = dev_get_drvdata(dev);
+ struct regmap *regmap = chip->regmap;
+ struct rtc_time *alrm_tm = &alrm->time;
+ u16 reg[8];
+ int year;
+ int ret;
+
+ /* our alarm has a limited year range... */
+ year = alrm_tm->tm_year - AC100_YEAR_OFF;
+ if (year < 0 || year > (AC100_YEAR_MAX - 1900)) {
+ dev_err(dev, "alarm only supports year in range %d - %d\n",
+ AC100_YEAR_MIN, AC100_YEAR_MAX);
+ return -EINVAL;
+ }
+
+ /* convert to BCD */
+ reg[0] = (bin2bcd(alrm_tm->tm_sec) & AC100_ALM_SEC_MASK) |
+ AC100_ALM_ENABLE_FLAG;
+ reg[1] = (bin2bcd(alrm_tm->tm_min) & AC100_ALM_MIN_MASK) |
+ AC100_ALM_ENABLE_FLAG;
+ reg[2] = (bin2bcd(alrm_tm->tm_hour) & AC100_ALM_HOU_MASK) |
+ AC100_ALM_ENABLE_FLAG;
+ /* Do not enable weekday alarm */
+ reg[3] = bin2bcd(alrm_tm->tm_wday) & AC100_ALM_WEE_MASK;
+ reg[4] = (bin2bcd(alrm_tm->tm_mday) & AC100_ALM_DAY_MASK) |
+ AC100_ALM_ENABLE_FLAG;
+ reg[5] = (bin2bcd(alrm_tm->tm_mon + 1) & AC100_ALM_MON_MASK) |
+ AC100_ALM_ENABLE_FLAG;
+ reg[6] = (bin2bcd(year) & AC100_ALM_YEA_MASK) |
+ AC100_ALM_ENABLE_FLAG;
+ /* trigger write */
+ reg[7] = AC100_ALM_UPD_TRIGGER;
+
+ ret = regmap_bulk_write(regmap, AC100_ALM_SEC, reg, 8);
+ if (ret)
+ return ret;
+
+ return ac100_rtc_alarm_irq_enable(dev, alrm->enabled);
+}
+
+static irqreturn_t ac100_rtc_irq(int irq, void *data)
+{
+ struct ac100_rtc_dev *chip = data;
+ struct regmap *regmap = chip->regmap;
+ unsigned int val = 0;
+ int ret;
+
+ mutex_lock(&chip->rtc->ops_lock);
+
+ /* read status */
+ ret = regmap_read(regmap, AC100_ALM_INT_STA, &val);
+ if (ret)
+ goto out;
+
+ if (val & AC100_ALM_INT_ENABLE) {
+ /* signal rtc framework */
+ rtc_update_irq(chip->rtc, 1, RTC_AF | RTC_IRQF);
+
+ /* clear status */
+ ret = regmap_write(regmap, AC100_ALM_INT_STA, val);
+ if (ret)
+ goto out;
+
+ /* disable interrupt */
+ ret = ac100_rtc_alarm_irq_enable(chip->dev, 0);
+ if (ret)
+ goto out;
+ }
+
+out:
+ mutex_unlock(&chip->rtc->ops_lock);
+ return IRQ_HANDLED;
+}
+
+static const struct rtc_class_ops ac100_rtc_ops = {
+ .read_time = ac100_rtc_get_time,
+ .set_time = ac100_rtc_set_time,
+ .read_alarm = ac100_rtc_get_alarm,
+ .set_alarm = ac100_rtc_set_alarm,
+ .alarm_irq_enable = ac100_rtc_alarm_irq_enable,
+};
+
+static int ac100_rtc_probe(struct platform_device *pdev)
+{
+ struct ac100_dev *ac100 = dev_get_drvdata(pdev->dev.parent);
+ struct ac100_rtc_dev *chip;
+ int ret;
+
+ chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
+ platform_set_drvdata(pdev, chip);
+ chip->dev = &pdev->dev;
+ chip->regmap = ac100->regmap;
+
+ chip->irq = platform_get_irq(pdev, 0);
+ if (chip->irq < 0) {
+ dev_err(&pdev->dev, "No IRQ resource\n");
+ return chip->irq;
+ }
+
+ ret = devm_request_threaded_irq(&pdev->dev, chip->irq, NULL,
+ ac100_rtc_irq,
+ IRQF_SHARED | IRQF_ONESHOT,
+ dev_name(&pdev->dev), chip);
+ if (ret) {
+ dev_err(&pdev->dev, "Could not request IRQ\n");
+ return ret;
+ }
+
+ /* always use 24 hour mode */
+ regmap_write_bits(chip->regmap, AC100_RTC_CTRL, AC100_RTC_CTRL_24HOUR,
+ AC100_RTC_CTRL_24HOUR);
+
+ /* disable counter alarm interrupt */
+ regmap_write(chip->regmap, AC100_ALM_INT_ENA, 0);
+
+ /* clear counter alarm pending interrupts */
+ regmap_write(chip->regmap, AC100_ALM_INT_STA, AC100_ALM_INT_ENABLE);
+
+ chip->rtc = devm_rtc_device_register(&pdev->dev, "rtc-ac100",
+ &ac100_rtc_ops, THIS_MODULE);
+ if (IS_ERR(chip->rtc)) {
+ dev_err(&pdev->dev, "unable to register device\n");
+ return PTR_ERR(chip->rtc);
+ }
+
+ ret = ac100_rtc_register_clks(chip);
+ if (ret)
+ return ret;
+
+ dev_info(&pdev->dev, "RTC enabled\n");
+
+ return 0;
+}
+
+static int ac100_rtc_remove(struct platform_device *pdev)
+{
+ struct ac100_rtc_dev *chip = platform_get_drvdata(pdev);
+
+ ac100_rtc_unregister_clks(chip);
+
+ return 0;
+}
+
+static const struct of_device_id ac100_rtc_match[] = {
+ { .compatible = "x-powers,ac100-rtc" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, ac100_rtc_match);
+
+static struct platform_driver ac100_rtc_driver = {
+ .probe = ac100_rtc_probe,
+ .remove = ac100_rtc_remove,
+ .driver = {
+ .name = "ac100-rtc",
+ .of_match_table = of_match_ptr(ac100_rtc_match),
+ },
+};
+module_platform_driver(ac100_rtc_driver);
+
+MODULE_DESCRIPTION("X-Powers AC100 RTC driver");
+MODULE_AUTHOR("Chen-Yu Tsai <wens@csie.org>");
+MODULE_LICENSE("GPL v2");