[PATCH 3/3] rtc: rv3032: Add a driver for Microcrystal RV-3032

From: Alexandre Belloni
Date: Mon Sep 21 2020 - 13:29:48 EST

New driver for the Microcrystal RV-3032, including support for:
- Date/time
- Alarms
- Low voltage detection
- Trickle charge
- Trimming
- Clkout
- RAM
- EEPROM

Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
---
drivers/rtc/Kconfig | 10 +
drivers/rtc/Makefile | 1 +
drivers/rtc/rtc-rv3032.c | 783 +++++++++++++++++++++++++++++++++++++++
3 files changed, 794 insertions(+)
create mode 100644 drivers/rtc/rtc-rv3032.c

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index b54d87d45c89..91faf74e188c 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -668,6 +668,16 @@ config RTC_DRV_RV3028
This driver can also be built as a module. If so, the module
will be called rtc-rv3028.

+config RTC_DRV_RV3032
+ tristate "Micro Crystal RV3032"
+ select REGMAP_I2C
+ help
+ If you say yes here you get support for the Micro Crystal
+ RV3032.
+
+ This driver can also be built as a module. If so, the module
+ will be called rtc-rv3032.
+
config RTC_DRV_RV8803
tristate "Micro Crystal RV8803, Epson RX8900"
help
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 0721752c6ed4..7bb8367538db 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -142,6 +142,7 @@ obj-$(CONFIG_RTC_DRV_RS5C372) += rtc-rs5c372.o
obj-$(CONFIG_RTC_DRV_RTD119X) += rtc-rtd119x.o
obj-$(CONFIG_RTC_DRV_RV3028) += rtc-rv3028.o
obj-$(CONFIG_RTC_DRV_RV3029C2) += rtc-rv3029c2.o
+obj-$(CONFIG_RTC_DRV_RV3032) += rtc-rv3032.o
obj-$(CONFIG_RTC_DRV_RV8803) += rtc-rv8803.o
obj-$(CONFIG_RTC_DRV_RX4581) += rtc-rx4581.o
obj-$(CONFIG_RTC_DRV_RX6110) += rtc-rx6110.o
diff --git a/drivers/rtc/rtc-rv3032.c b/drivers/rtc/rtc-rv3032.c
new file mode 100644
index 000000000000..1b0b0b5bf83a
--- /dev/null
+++ b/drivers/rtc/rtc-rv3032.c
@@ -0,0 +1,783 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * RTC driver for the Micro Crystal RV3032
+ *
+ * Copyright (C) 2020 Micro Crystal SA
+ *
+ * Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/bcd.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/log2.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/rtc.h>
+
+#define RV3032_SEC 0x01
+#define RV3032_MIN 0x02
+#define RV3032_HOUR 0x03
+#define RV3032_WDAY 0x04
+#define RV3032_DAY 0x05
+#define RV3032_MONTH 0x06
+#define RV3032_YEAR 0x07
+#define RV3032_ALARM_MIN 0x08
+#define RV3032_ALARM_HOUR 0x09
+#define RV3032_ALARM_DAY 0x0A
+#define RV3032_STATUS 0x0D
+#define RV3032_TLSB 0x0E
+#define RV3032_TMSB 0x0F
+#define RV3032_CTRL1 0x10
+#define RV3032_CTRL2 0x11
+#define RV3032_CTRL3 0x12
+#define RV3032_TS_CTRL 0x13
+#define RV3032_CLK_IRQ 0x14
+#define RV3032_EEPROM_ADDR 0x3D
+#define RV3032_EEPROM_DATA 0x3E
+#define RV3032_EEPROM_CMD 0x3F
+#define RV3032_RAM1 0x40
+#define RV3032_PMU 0xC0
+#define RV3032_OFFSET 0xC1
+#define RV3032_CLKOUT1 0xC2
+#define RV3032_CLKOUT2 0xC3
+#define RV3032_TREF0 0xC4
+#define RV3032_TREF1 0xC5
+
+#define RV3032_STATUS_VLF BIT(0)
+#define RV3032_STATUS_PORF BIT(1)
+#define RV3032_STATUS_EVF BIT(2)
+#define RV3032_STATUS_AF BIT(3)
+#define RV3032_STATUS_TF BIT(4)
+#define RV3032_STATUS_UF BIT(5)
+#define RV3032_STATUS_TLF BIT(6)
+#define RV3032_STATUS_THF BIT(7)
+
+#define RV3032_TLSB_CLKF BIT(1)
+#define RV3032_TLSB_EEBUSY BIT(2)
+
+#define RV3032_CLKOUT2_HFD_MSK GENMASK(4, 0)
+#define RV3032_CLKOUT2_FD_MSK GENMASK(6, 5)
+#define RV3032_CLKOUT2_OS BIT(7)
+
+#define RV3032_CTRL1_EERD BIT(3)
+#define RV3032_CTRL1_WADA BIT(5)
+
+#define RV3032_CTRL2_STOP BIT(0)
+#define RV3032_CTRL2_EIE BIT(2)
+#define RV3032_CTRL2_AIE BIT(3)
+#define RV3032_CTRL2_TIE BIT(4)
+#define RV3032_CTRL2_UIE BIT(5)
+#define RV3032_CTRL2_CLKIE BIT(6)
+#define RV3032_CTRL2_TSE BIT(7)
+
+#define RV3032_PMU_TCM GENMASK(1, 0)
+#define RV3032_PMU_TCR GENMASK(3, 2)
+#define RV3032_PMU_BSM GENMASK(5, 4)
+#define RV3032_PMU_NCLKE BIT(6)
+
+#define RV3032_PMU_BSM_DSM 1
+#define RV3032_PMU_BSM_LSM 2
+
+#define RV3032_OFFSET_MSK GENMASK(5, 0)
+
+#define RV3032_EVT_CTRL_TSR BIT(2)
+
+#define RV3032_EEPROM_CMD_WRITE 0x21
+#define RV3032_EEPROM_CMD_READ 0x22
+
+#define RV3032_EEPROM_USER 0xCB
+
+#define RV3032_EEBUSY_POLL 10000
+#define RV3032_EEBUSY_TIMEOUT 100000
+
+#define OFFSET_STEP_PPT 238419
+
+struct rv3032_data {
+ struct regmap *regmap;
+ struct rtc_device *rtc;
+#ifdef CONFIG_COMMON_CLK
+ struct clk_hw clkout_hw;
+#endif
+};
+
+static u16 rv3032_trickle_resistors[] = {1000, 2000, 7000, 11000};
+static u16 rv3032_trickle_voltages[] = {0, 1750, 3000, 4400};
+
+static irqreturn_t rv3032_handle_irq(int irq, void *dev_id)
+{
+ struct rv3032_data *rv3032 = dev_id;
+ unsigned long events = 0;
+ u32 status = 0, ctrl = 0;
+
+ if (regmap_read(rv3032->regmap, RV3032_STATUS, &status) < 0 ||
+ status == 0) {
+ return IRQ_NONE;
+ }
+
+ if (status & RV3032_STATUS_TF) {
+ status |= RV3032_STATUS_TF;
+ ctrl |= RV3032_CTRL2_TIE;
+ events |= RTC_PF;
+ }
+
+ if (status & RV3032_STATUS_AF) {
+ status |= RV3032_STATUS_AF;
+ ctrl |= RV3032_CTRL2_AIE;
+ events |= RTC_AF;
+ }
+
+ if (status & RV3032_STATUS_UF) {
+ status |= RV3032_STATUS_UF;
+ ctrl |= RV3032_CTRL2_UIE;
+ events |= RTC_UF;
+ }
+
+ if (events) {
+ rtc_update_irq(rv3032->rtc, 1, events);
+ regmap_update_bits(rv3032->regmap, RV3032_STATUS, status, 0);
+ regmap_update_bits(rv3032->regmap, RV3032_CTRL2, ctrl, 0);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int rv3032_get_time(struct device *dev, struct rtc_time *tm)
+{
+ struct rv3032_data *rv3032 = dev_get_drvdata(dev);
+ u8 date[7];
+ int ret, status;
+
+ ret = regmap_read(rv3032->regmap, RV3032_STATUS, &status);
+ if (ret < 0)
+ return ret;
+
+ if (status & (RV3032_STATUS_PORF | RV3032_STATUS_VLF))
+ return -EINVAL;
+
+ ret = regmap_bulk_read(rv3032->regmap, RV3032_SEC, date, sizeof(date));
+ if (ret)
+ return ret;
+
+ tm->tm_sec = bcd2bin(date[0] & 0x7f);
+ tm->tm_min = bcd2bin(date[1] & 0x7f);
+ tm->tm_hour = bcd2bin(date[2] & 0x3f);
+ tm->tm_wday = date[3] & 0x7;
+ tm->tm_mday = bcd2bin(date[4] & 0x3f);
+ tm->tm_mon = bcd2bin(date[5] & 0x1f) - 1;
+ tm->tm_year = bcd2bin(date[6]) + 100;
+
+ return 0;
+}
+
+static int rv3032_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct rv3032_data *rv3032 = dev_get_drvdata(dev);
+ u8 date[7];
+ int ret;
+
+ date[0] = bin2bcd(tm->tm_sec);
+ date[1] = bin2bcd(tm->tm_min);
+ date[2] = bin2bcd(tm->tm_hour);
+ date[3] = tm->tm_wday;
+ date[4] = bin2bcd(tm->tm_mday);
+ date[5] = bin2bcd(tm->tm_mon + 1);
+ date[6] = bin2bcd(tm->tm_year - 100);
+
+ ret = regmap_bulk_write(rv3032->regmap, RV3032_SEC, date,
+ sizeof(date));
+ if (ret)
+ return ret;
+
+ ret = regmap_update_bits(rv3032->regmap, RV3032_STATUS,
+ RV3032_STATUS_PORF | RV3032_STATUS_VLF, 0);
+
+ return ret;
+}
+
+static int rv3032_get_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct rv3032_data *rv3032 = dev_get_drvdata(dev);
+ u8 alarmvals[3];
+ int status, ctrl, ret;
+
+ ret = regmap_bulk_read(rv3032->regmap, RV3032_ALARM_MIN, alarmvals,
+ sizeof(alarmvals));
+ if (ret)
+ return ret;
+
+ ret = regmap_read(rv3032->regmap, RV3032_STATUS, &status);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_read(rv3032->regmap, RV3032_CTRL2, &ctrl);
+ if (ret < 0)
+ return ret;
+
+ alrm->time.tm_sec = 0;
+ alrm->time.tm_min = bcd2bin(alarmvals[0] & 0x7f);
+ alrm->time.tm_hour = bcd2bin(alarmvals[1] & 0x3f);
+ alrm->time.tm_mday = bcd2bin(alarmvals[2] & 0x3f);
+
+ alrm->enabled = !!(ctrl & RV3032_CTRL2_AIE);
+ alrm->pending = (status & RV3032_STATUS_AF) && alrm->enabled;
+
+ return 0;
+}
+
+static int rv3032_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct rv3032_data *rv3032 = dev_get_drvdata(dev);
+ u8 alarmvals[3];
+ u8 ctrl = 0;
+ int ret;
+
+ /* The alarm has no seconds, round up to nearest minute */
+ if (alrm->time.tm_sec) {
+ time64_t alarm_time = rtc_tm_to_time64(&alrm->time);
+
+ alarm_time += 60 - alrm->time.tm_sec;
+ rtc_time64_to_tm(alarm_time, &alrm->time);
+ }
+
+ ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL2,
+ RV3032_CTRL2_AIE | RV3032_CTRL2_UIE, 0);
+ if (ret)
+ return ret;
+
+ alarmvals[0] = bin2bcd(alrm->time.tm_min);
+ alarmvals[1] = bin2bcd(alrm->time.tm_hour);
+ alarmvals[2] = bin2bcd(alrm->time.tm_mday);
+
+ ret = regmap_update_bits(rv3032->regmap, RV3032_STATUS,
+ RV3032_STATUS_AF, 0);
+ if (ret)
+ return ret;
+
+ ret = regmap_bulk_write(rv3032->regmap, RV3032_ALARM_MIN, alarmvals,
+ sizeof(alarmvals));
+ if (ret)
+ return ret;
+
+ if (alrm->enabled) {
+ if (rv3032->rtc->uie_rtctimer.enabled)
+ ctrl |= RV3032_CTRL2_UIE;
+ if (rv3032->rtc->aie_timer.enabled)
+ ctrl |= RV3032_CTRL2_AIE;
+ }
+
+ ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL2,
+ RV3032_CTRL2_UIE | RV3032_CTRL2_AIE, ctrl);
+
+ return ret;
+}
+
+static int rv3032_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+ struct rv3032_data *rv3032 = dev_get_drvdata(dev);
+ int ctrl = 0, ret;
+
+ if (enabled) {
+ if (rv3032->rtc->uie_rtctimer.enabled)
+ ctrl |= RV3032_CTRL2_UIE;
+ if (rv3032->rtc->aie_timer.enabled)
+ ctrl |= RV3032_CTRL2_AIE;
+ }
+
+ ret = regmap_update_bits(rv3032->regmap, RV3032_STATUS,
+ RV3032_STATUS_AF | RV3032_STATUS_UF, 0);
+ if (ret)
+ return ret;
+
+ ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL2,
+ RV3032_CTRL2_UIE | RV3032_CTRL2_AIE, ctrl);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int rv3032_read_offset(struct device *dev, long *offset)
+{
+ struct rv3032_data *rv3032 = dev_get_drvdata(dev);
+ int ret, value, steps;
+
+ ret = regmap_read(rv3032->regmap, RV3032_OFFSET, &value);
+ if (ret < 0)
+ return ret;
+
+ steps = sign_extend32(FIELD_GET(RV3032_OFFSET_MSK, value), 5);
+
+ *offset = DIV_ROUND_CLOSEST(steps * OFFSET_STEP_PPT, 1000);
+
+ return 0;
+}
+
+static int rv3032_set_offset(struct device *dev, long offset)
+{
+ struct rv3032_data *rv3032 = dev_get_drvdata(dev);
+
+ offset = clamp(offset, -7629L, 7391L) * 1000;
+ offset = DIV_ROUND_CLOSEST(offset, OFFSET_STEP_PPT);
+
+ return regmap_update_bits(rv3032->regmap, RV3032_OFFSET, RV3032_OFFSET_MSK,
+ FIELD_PREP(RV3032_OFFSET_MSK, offset));
+}
+
+static int rv3032_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
+{
+ struct rv3032_data *rv3032 = dev_get_drvdata(dev);
+ int status, val = 0, ret = 0;
+
+ switch (cmd) {
+ case RTC_VL_READ:
+ ret = regmap_read(rv3032->regmap, RV3032_STATUS, &status);
+ if (ret < 0)
+ return ret;
+
+ if (status & (RV3032_STATUS_PORF | RV3032_STATUS_VLF))
+ val = RTC_VL_DATA_INVALID;
+ return put_user(val, (unsigned int __user *)arg);
+
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+static int rv3032_nvram_write(void *priv, unsigned int offset, void *val, size_t bytes)
+{
+ return regmap_bulk_write(priv, RV3032_RAM1 + offset, val, bytes);
+}
+
+static int rv3032_nvram_read(void *priv, unsigned int offset, void *val, size_t bytes)
+{
+ return regmap_bulk_read(priv, RV3032_RAM1 + offset, val, bytes);
+}
+
+static int rv3032_eeprom_write(void *priv, unsigned int offset, void *val, size_t bytes)
+{
+ u32 status, ctrl1;
+ int i, ret, err;
+ u8 *buf = val;
+
+ ret = regmap_read(priv, RV3032_CTRL1, &ctrl1);
+ if (ret)
+ return ret;
+
+ if (!(ctrl1 & RV3032_CTRL1_EERD)) {
+ ret = regmap_update_bits(priv, RV3032_CTRL1,
+ RV3032_CTRL1_EERD, RV3032_CTRL1_EERD);
+ if (ret)
+ return ret;
+
+ ret = regmap_read_poll_timeout(priv, RV3032_TLSB, status,
+ !(status & RV3032_TLSB_EEBUSY),
+ RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
+ if (ret)
+ goto restore_eerd;
+ }
+
+ for (i = 0; i < bytes; i++) {
+ ret = regmap_write(priv, RV3032_EEPROM_ADDR, RV3032_EEPROM_USER + offset + i);
+ if (ret)
+ goto restore_eerd;
+
+ ret = regmap_write(priv, RV3032_EEPROM_DATA, buf[i]);
+ if (ret)
+ goto restore_eerd;
+
+ ret = regmap_write(priv, RV3032_EEPROM_CMD, 0x0);
+ if (ret)
+ goto restore_eerd;
+
+ ret = regmap_write(priv, RV3032_EEPROM_CMD,
+ RV3032_EEPROM_CMD_WRITE);
+ if (ret)
+ goto restore_eerd;
+
+ usleep_range(RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
+
+ ret = regmap_read_poll_timeout(priv, RV3032_TLSB, status,
+ !(status & RV3032_TLSB_EEBUSY),
+ RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
+ if (ret)
+ goto restore_eerd;
+ }
+
+restore_eerd:
+ if (!(ctrl1 & RV3032_CTRL1_EERD)) {
+ err = regmap_update_bits(priv, RV3032_CTRL1, RV3032_CTRL1_EERD, 0);
+ if (err && !ret)
+ ret = err;
+ }
+
+ return ret;
+}
+
+static int rv3032_eeprom_read(void *priv, unsigned int offset, void *val, size_t bytes)
+{
+ u32 status, ctrl1, data;
+ int i, ret, err;
+ u8 *buf = val;
+
+ ret = regmap_read(priv, RV3032_CTRL1, &ctrl1);
+ if (ret)
+ return ret;
+
+ if (!(ctrl1 & RV3032_CTRL1_EERD)) {
+ ret = regmap_update_bits(priv, RV3032_CTRL1,
+ RV3032_CTRL1_EERD, RV3032_CTRL1_EERD);
+ if (ret)
+ return ret;
+
+ ret = regmap_read_poll_timeout(priv, RV3032_TLSB, status,
+ !(status & RV3032_TLSB_EEBUSY),
+ RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
+ if (ret)
+ goto restore_eerd;
+ }
+
+ for (i = 0; i < bytes; i++) {
+ ret = regmap_write(priv, RV3032_EEPROM_ADDR, RV3032_EEPROM_USER + offset + i);
+ if (ret)
+ goto restore_eerd;
+
+ ret = regmap_write(priv, RV3032_EEPROM_CMD, 0x0);
+ if (ret)
+ goto restore_eerd;
+
+ ret = regmap_write(priv, RV3032_EEPROM_CMD,
+ RV3032_EEPROM_CMD_READ);
+ if (ret)
+ goto restore_eerd;
+
+ ret = regmap_read_poll_timeout(priv, RV3032_TLSB, status,
+ !(status & RV3032_TLSB_EEBUSY),
+ RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
+ if (ret)
+ goto restore_eerd;
+
+ ret = regmap_read(priv, RV3032_EEPROM_DATA, &data);
+ if (ret)
+ goto restore_eerd;
+ buf[i] = data;
+ }
+
+restore_eerd:
+ if (!(ctrl1 & RV3032_CTRL1_EERD)) {
+ err = regmap_update_bits(priv, RV3032_CTRL1, RV3032_CTRL1_EERD, 0);
+ if (err && !ret)
+ ret = err;
+ }
+
+ return ret;
+}
+
+static int rv3032_trickle_charger_setup(struct device *dev, struct rv3032_data *rv3032)
+{
+ u32 val, ohms, voltage;
+ int i, ret;
+
+ val = FIELD_PREP(RV3032_PMU_TCM, 1) | FIELD_PREP(RV3032_PMU_BSM, RV3032_PMU_BSM_DSM);
+ if (!device_property_read_u32(dev, "trickle-voltage-mV", &voltage)) {
+ for (i = 0; i < ARRAY_SIZE(rv3032_trickle_voltages); i++)
+ if (voltage == rv3032_trickle_voltages[i])
+ break;
+ if (i < ARRAY_SIZE(rv3032_trickle_voltages))
+ val = FIELD_PREP(RV3032_PMU_TCM, i) |
+ FIELD_PREP(RV3032_PMU_BSM, RV3032_PMU_BSM_LSM);
+ }
+
+ if (!device_property_read_u32(dev, "trickle-resistor-ohms", &ohms)) {
+ for (i = 0; i < ARRAY_SIZE(rv3032_trickle_resistors); i++)
+ if (ohms == rv3032_trickle_resistors[i])
+ break;
+
+ if (i < ARRAY_SIZE(rv3032_trickle_resistors)) {
+ ret = regmap_update_bits(rv3032->regmap, RV3032_PMU,
+ RV3032_PMU_TCR | RV3032_PMU_TCM | RV3032_PMU_BSM,
+ FIELD_PREP(RV3032_PMU_TCR, i));
+ if (ret)
+ return ret;
+ } else {
+ dev_warn(dev, "invalid trickle resistor value\n");
+ }
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_COMMON_CLK
+#define clkout_hw_to_rv3032(hw) container_of(hw, struct rv3032_data, clkout_hw)
+
+static int clkout_xtal_rates[] = {
+ 32768,
+ 1024,
+ 64,
+ 1,
+};
+
+#define RV3032_HFD_STEP 8192
+
+static unsigned long rv3032_clkout_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ int clkout, ret;
+ struct rv3032_data *rv3032 = clkout_hw_to_rv3032(hw);
+
+ ret = regmap_read(rv3032->regmap, RV3032_CLKOUT2, &clkout);
+ if (ret < 0)
+ return 0;
+
+ if (clkout & RV3032_CLKOUT2_OS) {
+ unsigned long rate = FIELD_GET(RV3032_CLKOUT2_HFD_MSK, clkout) << 8;
+
+ ret = regmap_read(rv3032->regmap, RV3032_CLKOUT1, &clkout);
+ if (ret < 0)
+ return 0;
+
+ rate += clkout + 1;
+
+ return rate * RV3032_HFD_STEP;
+ }
+
+ return clkout_xtal_rates[FIELD_GET(RV3032_CLKOUT2_FD_MSK, clkout)];
+}
+
+static long rv3032_clkout_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ int i, hfd;
+
+ if (rate < RV3032_HFD_STEP)
+ for (i = 0; i < ARRAY_SIZE(clkout_xtal_rates); i++)
+ if (clkout_xtal_rates[i] <= rate)
+ return clkout_xtal_rates[i];
+
+ hfd = DIV_ROUND_CLOSEST(rate, RV3032_HFD_STEP);
+
+ return RV3032_HFD_STEP * clamp(hfd, 0, 8192);
+}
+
+static int rv3032_clkout_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct rv3032_data *rv3032 = clkout_hw_to_rv3032(hw);
+ int i, hfd, ret;
+
+ for (i = 0; i < ARRAY_SIZE(clkout_xtal_rates); i++) {
+ if (clkout_xtal_rates[i] == rate) {
+ return regmap_write(rv3032->regmap, RV3032_CLKOUT2,
+ FIELD_PREP(RV3032_CLKOUT2_FD_MSK, i));
+ }
+ }
+
+ hfd = DIV_ROUND_CLOSEST(rate, RV3032_HFD_STEP);
+ hfd = clamp(hfd, 1, 8192) - 1;
+
+ ret = regmap_write(rv3032->regmap, RV3032_CLKOUT1, hfd & 0xff);
+ if (ret < 0)
+ return ret;
+
+ return regmap_write(rv3032->regmap, RV3032_CLKOUT2, RV3032_CLKOUT2_OS |
+ FIELD_PREP(RV3032_CLKOUT2_HFD_MSK, hfd >> 8));
+}
+
+static int rv3032_clkout_prepare(struct clk_hw *hw)
+{
+ struct rv3032_data *rv3032 = clkout_hw_to_rv3032(hw);
+
+ return regmap_update_bits(rv3032->regmap, RV3032_PMU,
+ RV3032_PMU_NCLKE, 0);
+}
+
+static void rv3032_clkout_unprepare(struct clk_hw *hw)
+{
+ struct rv3032_data *rv3032 = clkout_hw_to_rv3032(hw);
+
+ regmap_update_bits(rv3032->regmap, RV3032_PMU,
+ RV3032_PMU_NCLKE, RV3032_PMU_NCLKE);
+}
+
+static int rv3032_clkout_is_prepared(struct clk_hw *hw)
+{
+ int val, ret;
+ struct rv3032_data *rv3032 = clkout_hw_to_rv3032(hw);
+
+ ret = regmap_read(rv3032->regmap, RV3032_PMU, &val);
+ if (ret < 0)
+ return ret;
+
+ return !(val & RV3032_PMU_NCLKE);
+}
+
+static const struct clk_ops rv3032_clkout_ops = {
+ .prepare = rv3032_clkout_prepare,
+ .unprepare = rv3032_clkout_unprepare,
+ .is_prepared = rv3032_clkout_is_prepared,
+ .recalc_rate = rv3032_clkout_recalc_rate,
+ .round_rate = rv3032_clkout_round_rate,
+ .set_rate = rv3032_clkout_set_rate,
+};
+
+static int rv3032_clkout_register_clk(struct rv3032_data *rv3032,
+ struct i2c_client *client)
+{
+ int ret;
+ struct clk *clk;
+ struct clk_init_data init;
+ struct device_node *node = client->dev.of_node;
+
+ ret = regmap_update_bits(rv3032->regmap, RV3032_TLSB, RV3032_TLSB_CLKF, 0);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL2, RV3032_CTRL2_CLKIE, 0);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_write(rv3032->regmap, RV3032_CLK_IRQ, 0);
+ if (ret < 0)
+ return ret;
+
+ init.name = "rv3032-clkout";
+ init.ops = &rv3032_clkout_ops;
+ init.flags = 0;
+ init.parent_names = NULL;
+ init.num_parents = 0;
+ rv3032->clkout_hw.init = &init;
+
+ of_property_read_string(node, "clock-output-names", &init.name);
+
+ clk = devm_clk_register(&client->dev, &rv3032->clkout_hw);
+ if (!IS_ERR(clk))
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+
+ return 0;
+}
+#endif
+
+static struct rtc_class_ops rv3032_rtc_ops = {
+ .read_time = rv3032_get_time,
+ .set_time = rv3032_set_time,
+ .read_offset = rv3032_read_offset,
+ .set_offset = rv3032_set_offset,
+ .ioctl = rv3032_ioctl,
+};
+
+static const struct regmap_config regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .max_register = 0xCA,
+};
+
+static int rv3032_probe(struct i2c_client *client)
+{
+ struct rv3032_data *rv3032;
+ int ret, status;
+ struct nvmem_config nvmem_cfg = {
+ .name = "rv3032_nvram",
+ .word_size = 1,
+ .stride = 1,
+ .size = 16,
+ .type = NVMEM_TYPE_BATTERY_BACKED,
+ .reg_read = rv3032_nvram_read,
+ .reg_write = rv3032_nvram_write,
+ };
+ struct nvmem_config eeprom_cfg = {
+ .name = "rv3032_eeprom",
+ .word_size = 1,
+ .stride = 1,
+ .size = 32,
+ .type = NVMEM_TYPE_EEPROM,
+ .reg_read = rv3032_eeprom_read,
+ .reg_write = rv3032_eeprom_write,
+ };
+
+ rv3032 = devm_kzalloc(&client->dev, sizeof(struct rv3032_data),
+ GFP_KERNEL);
+ if (!rv3032)
+ return -ENOMEM;
+
+ rv3032->regmap = devm_regmap_init_i2c(client, &regmap_config);
+ if (IS_ERR(rv3032->regmap))
+ return PTR_ERR(rv3032->regmap);
+
+ i2c_set_clientdata(client, rv3032);
+
+ ret = regmap_read(rv3032->regmap, RV3032_STATUS, &status);
+ if (ret < 0)
+ return ret;
+
+ rv3032->rtc = devm_rtc_allocate_device(&client->dev);
+ if (IS_ERR(rv3032->rtc))
+ return PTR_ERR(rv3032->rtc);
+
+ if (client->irq > 0) {
+ ret = devm_request_threaded_irq(&client->dev, client->irq,
+ NULL, rv3032_handle_irq,
+ IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+ "rv3032", rv3032);
+ if (ret) {
+ dev_warn(&client->dev, "unable to request IRQ, alarms disabled\n");
+ client->irq = 0;
+ } else {
+ rv3032_rtc_ops.read_alarm = rv3032_get_alarm;
+ rv3032_rtc_ops.set_alarm = rv3032_set_alarm;
+ rv3032_rtc_ops.alarm_irq_enable = rv3032_alarm_irq_enable;
+ }
+ }
+
+ ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL1,
+ RV3032_CTRL1_WADA, RV3032_CTRL1_WADA);
+ if (ret)
+ return ret;
+
+ rv3032_trickle_charger_setup(&client->dev, rv3032);
+
+ rv3032->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
+ rv3032->rtc->range_max = RTC_TIMESTAMP_END_2099;
+ rv3032->rtc->ops = &rv3032_rtc_ops;
+ ret = rtc_register_device(rv3032->rtc);
+ if (ret)
+ return ret;
+
+ nvmem_cfg.priv = rv3032->regmap;
+ rtc_nvmem_register(rv3032->rtc, &nvmem_cfg);
+ eeprom_cfg.priv = rv3032->regmap;
+ rtc_nvmem_register(rv3032->rtc, &eeprom_cfg);
+
+ rv3032->rtc->max_user_freq = 1;
+
+#ifdef CONFIG_COMMON_CLK
+ rv3032_clkout_register_clk(rv3032, client);
+#endif
+
+ return 0;
+}
+
+static const struct of_device_id rv3032_of_match[] = {
+ { .compatible = "microcrystal,rv3032", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, rv3032_of_match);
+
+static struct i2c_driver rv3032_driver = {
+ .driver = {
+ .name = "rtc-rv3032",
+ .of_match_table = of_match_ptr(rv3032_of_match),
+ },
+ .probe_new = rv3032_probe,
+};
+module_i2c_driver(rv3032_driver);
+
+MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>");
+MODULE_DESCRIPTION("Micro Crystal RV3032 RTC driver");
+MODULE_LICENSE("GPL v2");
--
2.26.2