openwrt/target/linux/bcm27xx/patches-4.19/950-0339-rtc-rv3028-add-new-driver.patch
Adrian Schmutzler 7d7aa2fd92 brcm2708: rename target to bcm27xx
This change makes the names of Broadcom targets consistent by using
the common notation based on SoC/CPU ID (which is used internally
anyway), bcmXXXX instead of brcmXXXX.
This is even used for target TITLE in make menuconfig already,
only the short target name used brcm so far.

Despite, since subtargets range from bcm2708 to bcm2711, it seems
appropriate to use bcm27xx instead of bcm2708 (again, as already done
for BOARDNAME).

This also renames the packages brcm2708-userland and brcm2708-gpu-fw.

Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
Acked-by: Álvaro Fernández Rojas <noltari@gmail.com>
2020-02-14 14:10:51 +01:00

861 lines
23 KiB
Diff

From bb0e317bfc453877805a12f975490ad38b6413f1 Mon Sep 17 00:00:00 2001
From: Alexandre Belloni <alexandre.belloni@bootlin.com>
Date: Wed, 13 Feb 2019 00:21:36 +0100
Subject: [PATCH] rtc: rv3028: add new driver
upstream commit e6e7376cfd7b3f9b63de3a22792f64d9bfb2ab53.
Add a driver for the MicroCrystal RV-3028. It is a SMT Real-Time Clock
Module that incorporates an integrated CMOS circuit together with an XTAL.
It has an i2c interface.
The driver handles date/time, alarms, trickle charging, timestamping,
frequency offset correction, EEPROM and NVRAM.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
---
Documentation/devicetree/bindings/rtc/rtc.txt | 69 ++
drivers/rtc/Kconfig | 9 +
drivers/rtc/Makefile | 1 +
drivers/rtc/rtc-rv3028.c | 733 ++++++++++++++++++
4 files changed, 812 insertions(+)
create mode 100644 Documentation/devicetree/bindings/rtc/rtc.txt
create mode 100644 drivers/rtc/rtc-rv3028.c
--- /dev/null
+++ b/Documentation/devicetree/bindings/rtc/rtc.txt
@@ -0,0 +1,69 @@
+Generic device tree bindings for Real Time Clock devices
+========================================================
+
+This document describes generic bindings which can be used to describe Real Time
+Clock devices in a device tree.
+
+Required properties
+-------------------
+
+- compatible : name of RTC device following generic names recommended practice.
+
+For other required properties e.g. to describe register sets,
+clocks, etc. check the binding documentation of the specific driver.
+
+Optional properties
+-------------------
+
+- start-year : if provided, the default hardware range supported by the RTC is
+ shifted so the first usable year is the specified one.
+
+The following properties may not be supported by all drivers. However, if a
+driver wants to support one of the below features, it should adapt the bindings
+below.
+- trickle-resistor-ohms : Selected resistor for trickle charger. Should be given
+ if trickle charger should be enabled
+- trickle-diode-disable : Do not use internal trickle charger diode Should be
+ given if internal trickle charger diode should be
+ disabled
+- wakeup-source : Enables wake up of host system on alarm
+- quartz-load-femtofarads : The capacitive load of the quartz(x-tal),
+ expressed in femto Farad (fF).
+ The default value shall be listed (if optional),
+ and likewise all valid values.
+
+Trivial RTCs
+------------
+
+This is a list of trivial RTC devices that have simple device tree
+bindings, consisting only of a compatible field, an address and
+possibly an interrupt line.
+
+
+Compatible Vendor / Chip
+========== =============
+abracon,abb5zes3 AB-RTCMC-32.768kHz-B5ZE-S3: Real Time Clock/Calendar Module with I2C Interface
+dallas,ds1374 I2C, 32-Bit Binary Counter Watchdog RTC with Trickle Charger and Reset Input/Output
+dallas,ds1672 Dallas DS1672 Real-time Clock
+dallas,ds3232 Extremely Accurate I²C RTC with Integrated Crystal and SRAM
+epson,rx8010 I2C-BUS INTERFACE REAL TIME CLOCK MODULE
+epson,rx8581 I2C-BUS INTERFACE REAL TIME CLOCK MODULE
+emmicro,em3027 EM Microelectronic EM3027 Real-time Clock
+isil,isl1208 Intersil ISL1208 Low Power RTC with Battery Backed SRAM
+isil,isl1218 Intersil ISL1218 Low Power RTC with Battery Backed SRAM
+isil,isl12022 Intersil ISL12022 Real-time Clock
+microcrystal,rv3028 Real Time Clock Module with I2C-Bus
+microcrystal,rv3029 Real Time Clock Module with I2C-Bus
+microcrystal,rv8523 Real Time Clock
+nxp,pcf2127 Real-time clock
+nxp,pcf2129 Real-time clock
+nxp,pcf8563 Real-time clock/calendar
+pericom,pt7c4338 Real-time Clock Module
+ricoh,r2025sd I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
+ricoh,r2221tl I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
+ricoh,rs5c372a I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
+ricoh,rs5c372b I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
+ricoh,rv5c386 I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
+ricoh,rv5c387a I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
+sii,s35390a 2-wire CMOS real-time clock
+whwave,sd3078 I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -625,6 +625,15 @@ config RTC_DRV_EM3027
This driver can also be built as a module. If so, the module
will be called rtc-em3027.
+config RTC_DRV_RV3028
+ tristate "Micro Crystal RV3028"
+ help
+ If you say yes here you get support for the Micro Crystal
+ RV3028.
+
+ This driver can also be built as a module. If so, the module
+ will be called rtc-rv3028.
+
config RTC_DRV_RV8803
tristate "Micro Crystal RV8803, Epson RX8900"
help
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -136,6 +136,7 @@ obj-$(CONFIG_RTC_DRV_RS5C313) += rtc-rs5
obj-$(CONFIG_RTC_DRV_RS5C348) += rtc-rs5c348.o
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-$(CONFIG_RTC_DRV_RV8803) += rtc-rv8803.o
obj-$(CONFIG_RTC_DRV_RX4581) += rtc-rx4581.o
--- /dev/null
+++ b/drivers/rtc/rtc-rv3028.c
@@ -0,0 +1,733 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * RTC driver for the Micro Crystal RV3028
+ *
+ * Copyright (C) 2019 Micro Crystal SA
+ *
+ * Alexandre Belloni <alexandre.belloni@bootlin.com>
+ *
+ */
+
+#include <linux/bcd.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>
+#include "rtc-core.h"
+
+#define RV3028_SEC 0x00
+#define RV3028_MIN 0x01
+#define RV3028_HOUR 0x02
+#define RV3028_WDAY 0x03
+#define RV3028_DAY 0x04
+#define RV3028_MONTH 0x05
+#define RV3028_YEAR 0x06
+#define RV3028_ALARM_MIN 0x07
+#define RV3028_ALARM_HOUR 0x08
+#define RV3028_ALARM_DAY 0x09
+#define RV3028_STATUS 0x0E
+#define RV3028_CTRL1 0x0F
+#define RV3028_CTRL2 0x10
+#define RV3028_EVT_CTRL 0x13
+#define RV3028_TS_COUNT 0x14
+#define RV3028_TS_SEC 0x15
+#define RV3028_RAM1 0x1F
+#define RV3028_EEPROM_ADDR 0x25
+#define RV3028_EEPROM_DATA 0x26
+#define RV3028_EEPROM_CMD 0x27
+#define RV3028_CLKOUT 0x35
+#define RV3028_OFFSET 0x36
+#define RV3028_BACKUP 0x37
+
+#define RV3028_STATUS_PORF BIT(0)
+#define RV3028_STATUS_EVF BIT(1)
+#define RV3028_STATUS_AF BIT(2)
+#define RV3028_STATUS_TF BIT(3)
+#define RV3028_STATUS_UF BIT(4)
+#define RV3028_STATUS_BSF BIT(5)
+#define RV3028_STATUS_CLKF BIT(6)
+#define RV3028_STATUS_EEBUSY BIT(7)
+
+#define RV3028_CTRL1_EERD BIT(3)
+#define RV3028_CTRL1_WADA BIT(5)
+
+#define RV3028_CTRL2_RESET BIT(0)
+#define RV3028_CTRL2_12_24 BIT(1)
+#define RV3028_CTRL2_EIE BIT(2)
+#define RV3028_CTRL2_AIE BIT(3)
+#define RV3028_CTRL2_TIE BIT(4)
+#define RV3028_CTRL2_UIE BIT(5)
+#define RV3028_CTRL2_TSE BIT(7)
+
+#define RV3028_EVT_CTRL_TSR BIT(2)
+
+#define RV3028_EEPROM_CMD_WRITE 0x21
+#define RV3028_EEPROM_CMD_READ 0x22
+
+#define RV3028_EEBUSY_POLL 10000
+#define RV3028_EEBUSY_TIMEOUT 100000
+
+#define RV3028_BACKUP_TCE BIT(5)
+#define RV3028_BACKUP_TCR_MASK GENMASK(1,0)
+
+#define OFFSET_STEP_PPT 953674
+
+enum rv3028_type {
+ rv_3028,
+};
+
+struct rv3028_data {
+ struct regmap *regmap;
+ struct rtc_device *rtc;
+ enum rv3028_type type;
+};
+
+static u16 rv3028_trickle_resistors[] = {1000, 3000, 6000, 11000};
+
+static ssize_t timestamp0_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct rv3028_data *rv3028 = dev_get_drvdata(dev->parent);
+
+ regmap_update_bits(rv3028->regmap, RV3028_EVT_CTRL, RV3028_EVT_CTRL_TSR,
+ RV3028_EVT_CTRL_TSR);
+
+ return count;
+};
+
+static ssize_t timestamp0_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct rv3028_data *rv3028 = dev_get_drvdata(dev->parent);
+ struct rtc_time tm;
+ int ret, count;
+ u8 date[6];
+
+ ret = regmap_read(rv3028->regmap, RV3028_TS_COUNT, &count);
+ if (ret)
+ return ret;
+
+ if (!count)
+ return 0;
+
+ ret = regmap_bulk_read(rv3028->regmap, RV3028_TS_SEC, date,
+ sizeof(date));
+ if (ret)
+ return ret;
+
+ tm.tm_sec = bcd2bin(date[0]);
+ tm.tm_min = bcd2bin(date[1]);
+ tm.tm_hour = bcd2bin(date[2]);
+ tm.tm_mday = bcd2bin(date[3]);
+ tm.tm_mon = bcd2bin(date[4]) - 1;
+ tm.tm_year = bcd2bin(date[5]) + 100;
+
+ ret = rtc_valid_tm(&tm);
+ if (ret)
+ return ret;
+
+ return sprintf(buf, "%llu\n",
+ (unsigned long long)rtc_tm_to_time64(&tm));
+};
+
+static DEVICE_ATTR_RW(timestamp0);
+
+static ssize_t timestamp0_count_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct rv3028_data *rv3028 = dev_get_drvdata(dev->parent);
+ int ret, count;
+
+ ret = regmap_read(rv3028->regmap, RV3028_TS_COUNT, &count);
+ if (ret)
+ return ret;
+
+ return sprintf(buf, "%u\n", count);
+};
+
+static DEVICE_ATTR_RO(timestamp0_count);
+
+static struct attribute *rv3028_attrs[] = {
+ &dev_attr_timestamp0.attr,
+ &dev_attr_timestamp0_count.attr,
+ NULL
+};
+
+static const struct attribute_group rv3028_attr_group = {
+ .attrs = rv3028_attrs,
+};
+
+static irqreturn_t rv3028_handle_irq(int irq, void *dev_id)
+{
+ struct rv3028_data *rv3028 = dev_id;
+ unsigned long events = 0;
+ u32 status = 0, ctrl = 0;
+
+ if (regmap_read(rv3028->regmap, RV3028_STATUS, &status) < 0 ||
+ status == 0) {
+ return IRQ_NONE;
+ }
+
+ if (status & RV3028_STATUS_PORF)
+ dev_warn(&rv3028->rtc->dev, "Voltage low, data loss detected.\n");
+
+ if (status & RV3028_STATUS_TF) {
+ status |= RV3028_STATUS_TF;
+ ctrl |= RV3028_CTRL2_TIE;
+ events |= RTC_PF;
+ }
+
+ if (status & RV3028_STATUS_AF) {
+ status |= RV3028_STATUS_AF;
+ ctrl |= RV3028_CTRL2_AIE;
+ events |= RTC_AF;
+ }
+
+ if (status & RV3028_STATUS_UF) {
+ status |= RV3028_STATUS_UF;
+ ctrl |= RV3028_CTRL2_UIE;
+ events |= RTC_UF;
+ }
+
+ if (events) {
+ rtc_update_irq(rv3028->rtc, 1, events);
+ regmap_update_bits(rv3028->regmap, RV3028_STATUS, status, 0);
+ regmap_update_bits(rv3028->regmap, RV3028_CTRL2, ctrl, 0);
+ }
+
+ if (status & RV3028_STATUS_EVF) {
+ sysfs_notify(&rv3028->rtc->dev.kobj, NULL,
+ dev_attr_timestamp0.attr.name);
+ dev_warn(&rv3028->rtc->dev, "event detected");
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int rv3028_get_time(struct device *dev, struct rtc_time *tm)
+{
+ struct rv3028_data *rv3028 = dev_get_drvdata(dev);
+ u8 date[7];
+ int ret, status;
+
+ ret = regmap_read(rv3028->regmap, RV3028_STATUS, &status);
+ if (ret < 0)
+ return ret;
+
+ if (status & RV3028_STATUS_PORF) {
+ dev_warn(dev, "Voltage low, data is invalid.\n");
+ return -EINVAL;
+ }
+
+ ret = regmap_bulk_read(rv3028->regmap, RV3028_SEC, date, sizeof(date));
+ if (ret)
+ return ret;
+
+ tm->tm_sec = bcd2bin(date[RV3028_SEC] & 0x7f);
+ tm->tm_min = bcd2bin(date[RV3028_MIN] & 0x7f);
+ tm->tm_hour = bcd2bin(date[RV3028_HOUR] & 0x3f);
+ tm->tm_wday = ilog2(date[RV3028_WDAY] & 0x7f);
+ tm->tm_mday = bcd2bin(date[RV3028_DAY] & 0x3f);
+ tm->tm_mon = bcd2bin(date[RV3028_MONTH] & 0x1f) - 1;
+ tm->tm_year = bcd2bin(date[RV3028_YEAR]) + 100;
+
+ return 0;
+}
+
+static int rv3028_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct rv3028_data *rv3028 = dev_get_drvdata(dev);
+ u8 date[7];
+ int ret;
+
+ date[RV3028_SEC] = bin2bcd(tm->tm_sec);
+ date[RV3028_MIN] = bin2bcd(tm->tm_min);
+ date[RV3028_HOUR] = bin2bcd(tm->tm_hour);
+ date[RV3028_WDAY] = 1 << (tm->tm_wday);
+ date[RV3028_DAY] = bin2bcd(tm->tm_mday);
+ date[RV3028_MONTH] = bin2bcd(tm->tm_mon + 1);
+ date[RV3028_YEAR] = bin2bcd(tm->tm_year - 100);
+
+ /*
+ * Writing to the Seconds register has the same effect as setting RESET
+ * bit to 1
+ */
+ ret = regmap_bulk_write(rv3028->regmap, RV3028_SEC, date,
+ sizeof(date));
+ if (ret)
+ return ret;
+
+ ret = regmap_update_bits(rv3028->regmap, RV3028_STATUS,
+ RV3028_STATUS_PORF, 0);
+
+ return ret;
+}
+
+static int rv3028_get_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct rv3028_data *rv3028 = dev_get_drvdata(dev);
+ u8 alarmvals[3];
+ int status, ctrl, ret;
+
+ ret = regmap_bulk_read(rv3028->regmap, RV3028_ALARM_MIN, alarmvals,
+ sizeof(alarmvals));
+ if (ret)
+ return ret;
+
+ ret = regmap_read(rv3028->regmap, RV3028_STATUS, &status);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_read(rv3028->regmap, RV3028_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 & RV3028_CTRL2_AIE);
+ alrm->pending = (status & RV3028_STATUS_AF) && alrm->enabled;
+
+ return 0;
+}
+
+static int rv3028_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct rv3028_data *rv3028 = 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(rv3028->regmap, RV3028_CTRL2,
+ RV3028_CTRL2_AIE | RV3028_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(rv3028->regmap, RV3028_STATUS,
+ RV3028_STATUS_AF, 0);
+ if (ret)
+ return ret;
+
+ ret = regmap_bulk_write(rv3028->regmap, RV3028_ALARM_MIN, alarmvals,
+ sizeof(alarmvals));
+ if (ret)
+ return ret;
+
+ if (alrm->enabled) {
+ if (rv3028->rtc->uie_rtctimer.enabled)
+ ctrl |= RV3028_CTRL2_UIE;
+ if (rv3028->rtc->aie_timer.enabled)
+ ctrl |= RV3028_CTRL2_AIE;
+ }
+
+ ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL2,
+ RV3028_CTRL2_UIE | RV3028_CTRL2_AIE, ctrl);
+
+ return ret;
+}
+
+static int rv3028_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+ struct rv3028_data *rv3028 = dev_get_drvdata(dev);
+ int ctrl = 0, ret;
+
+ if (enabled) {
+ if (rv3028->rtc->uie_rtctimer.enabled)
+ ctrl |= RV3028_CTRL2_UIE;
+ if (rv3028->rtc->aie_timer.enabled)
+ ctrl |= RV3028_CTRL2_AIE;
+ }
+
+ ret = regmap_update_bits(rv3028->regmap, RV3028_STATUS,
+ RV3028_STATUS_AF | RV3028_STATUS_UF, 0);
+ if (ret)
+ return ret;
+
+ ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL2,
+ RV3028_CTRL2_UIE | RV3028_CTRL2_AIE, ctrl);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int rv3028_read_offset(struct device *dev, long *offset)
+{
+ struct rv3028_data *rv3028 = dev_get_drvdata(dev);
+ int ret, value, steps;
+
+ ret = regmap_read(rv3028->regmap, RV3028_OFFSET, &value);
+ if (ret < 0)
+ return ret;
+
+ steps = sign_extend32(value << 1, 8);
+
+ ret = regmap_read(rv3028->regmap, RV3028_BACKUP, &value);
+ if (ret < 0)
+ return ret;
+
+ steps += value >> 7;
+
+ *offset = DIV_ROUND_CLOSEST(steps * OFFSET_STEP_PPT, 1000);
+
+ return 0;
+}
+
+static int rv3028_set_offset(struct device *dev, long offset)
+{
+ struct rv3028_data *rv3028 = dev_get_drvdata(dev);
+ int ret;
+
+ offset = clamp(offset, -244141L, 243187L) * 1000;
+ offset = DIV_ROUND_CLOSEST(offset, OFFSET_STEP_PPT);
+
+ ret = regmap_write(rv3028->regmap, RV3028_OFFSET, offset >> 1);
+ if (ret < 0)
+ return ret;
+
+ return regmap_update_bits(rv3028->regmap, RV3028_BACKUP, BIT(7),
+ offset << 7);
+}
+
+static int rv3028_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
+{
+ struct rv3028_data *rv3028 = dev_get_drvdata(dev);
+ int status, ret = 0;
+
+ switch (cmd) {
+ case RTC_VL_READ:
+ ret = regmap_read(rv3028->regmap, RV3028_STATUS, &status);
+ if (ret < 0)
+ return ret;
+
+ if (status & RV3028_STATUS_PORF)
+ dev_warn(&rv3028->rtc->dev, "Voltage low, data loss detected.\n");
+
+ status &= RV3028_STATUS_PORF;
+
+ if (copy_to_user((void __user *)arg, &status, sizeof(int)))
+ return -EFAULT;
+
+ return 0;
+
+ case RTC_VL_CLR:
+ ret = regmap_update_bits(rv3028->regmap, RV3028_STATUS,
+ RV3028_STATUS_PORF, 0);
+
+ return ret;
+
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+static int rv3028_nvram_write(void *priv, unsigned int offset, void *val,
+ size_t bytes)
+{
+ return regmap_bulk_write(priv, RV3028_RAM1 + offset, val, bytes);
+}
+
+static int rv3028_nvram_read(void *priv, unsigned int offset, void *val,
+ size_t bytes)
+{
+ return regmap_bulk_read(priv, RV3028_RAM1 + offset, val, bytes);
+}
+
+static int rv3028_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, RV3028_CTRL1, &ctrl1);
+ if (ret)
+ return ret;
+
+ if (!(ctrl1 & RV3028_CTRL1_EERD)) {
+ ret = regmap_update_bits(priv, RV3028_CTRL1,
+ RV3028_CTRL1_EERD, RV3028_CTRL1_EERD);
+ if (ret)
+ return ret;
+
+ ret = regmap_read_poll_timeout(priv, RV3028_STATUS, status,
+ !(status & RV3028_STATUS_EEBUSY),
+ RV3028_EEBUSY_POLL,
+ RV3028_EEBUSY_TIMEOUT);
+ if (ret)
+ goto restore_eerd;
+ }
+
+ for (i = 0; i < bytes; i++) {
+ ret = regmap_write(priv, RV3028_EEPROM_ADDR, offset + i);
+ if (ret)
+ goto restore_eerd;
+
+ ret = regmap_write(priv, RV3028_EEPROM_DATA, buf[i]);
+ if (ret)
+ goto restore_eerd;
+
+ ret = regmap_write(priv, RV3028_EEPROM_CMD, 0x0);
+ if (ret)
+ goto restore_eerd;
+
+ ret = regmap_write(priv, RV3028_EEPROM_CMD,
+ RV3028_EEPROM_CMD_WRITE);
+ if (ret)
+ goto restore_eerd;
+
+ usleep_range(RV3028_EEBUSY_POLL, RV3028_EEBUSY_TIMEOUT);
+
+ ret = regmap_read_poll_timeout(priv, RV3028_STATUS, status,
+ !(status & RV3028_STATUS_EEBUSY),
+ RV3028_EEBUSY_POLL,
+ RV3028_EEBUSY_TIMEOUT);
+ if (ret)
+ goto restore_eerd;
+ }
+
+restore_eerd:
+ if (!(ctrl1 & RV3028_CTRL1_EERD))
+ {
+ err = regmap_update_bits(priv, RV3028_CTRL1, RV3028_CTRL1_EERD,
+ 0);
+ if (err && !ret)
+ ret = err;
+ }
+
+ return ret;
+}
+
+static int rv3028_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, RV3028_CTRL1, &ctrl1);
+ if (ret)
+ return ret;
+
+ if (!(ctrl1 & RV3028_CTRL1_EERD)) {
+ ret = regmap_update_bits(priv, RV3028_CTRL1,
+ RV3028_CTRL1_EERD, RV3028_CTRL1_EERD);
+ if (ret)
+ return ret;
+
+ ret = regmap_read_poll_timeout(priv, RV3028_STATUS, status,
+ !(status & RV3028_STATUS_EEBUSY),
+ RV3028_EEBUSY_POLL,
+ RV3028_EEBUSY_TIMEOUT);
+ if (ret)
+ goto restore_eerd;
+ }
+
+ for (i = 0; i < bytes; i++) {
+ ret = regmap_write(priv, RV3028_EEPROM_ADDR, offset + i);
+ if (ret)
+ goto restore_eerd;
+
+ ret = regmap_write(priv, RV3028_EEPROM_CMD, 0x0);
+ if (ret)
+ goto restore_eerd;
+
+ ret = regmap_write(priv, RV3028_EEPROM_CMD,
+ RV3028_EEPROM_CMD_READ);
+ if (ret)
+ goto restore_eerd;
+
+ ret = regmap_read_poll_timeout(priv, RV3028_STATUS, status,
+ !(status & RV3028_STATUS_EEBUSY),
+ RV3028_EEBUSY_POLL,
+ RV3028_EEBUSY_TIMEOUT);
+ if (ret)
+ goto restore_eerd;
+
+ ret = regmap_read(priv, RV3028_EEPROM_DATA, &data);
+ if (ret)
+ goto restore_eerd;
+ buf[i] = data;
+ }
+
+restore_eerd:
+ if (!(ctrl1 & RV3028_CTRL1_EERD))
+ {
+ err = regmap_update_bits(priv, RV3028_CTRL1, RV3028_CTRL1_EERD,
+ 0);
+ if (err && !ret)
+ ret = err;
+ }
+
+ return ret;
+}
+
+static struct rtc_class_ops rv3028_rtc_ops = {
+ .read_time = rv3028_get_time,
+ .set_time = rv3028_set_time,
+ .read_offset = rv3028_read_offset,
+ .set_offset = rv3028_set_offset,
+ .ioctl = rv3028_ioctl,
+};
+
+static const struct regmap_config regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .max_register = 0x37,
+};
+
+static int rv3028_probe(struct i2c_client *client)
+{
+ struct rv3028_data *rv3028;
+ int ret, status;
+ u32 ohms;
+ struct nvmem_config nvmem_cfg = {
+ .name = "rv3028_nvram",
+ .word_size = 1,
+ .stride = 1,
+ .size = 2,
+ .type = NVMEM_TYPE_BATTERY_BACKED,
+ .reg_read = rv3028_nvram_read,
+ .reg_write = rv3028_nvram_write,
+ };
+ struct nvmem_config eeprom_cfg = {
+ .name = "rv3028_eeprom",
+ .word_size = 1,
+ .stride = 1,
+ .size = 43,
+ .type = NVMEM_TYPE_EEPROM,
+ .reg_read = rv3028_eeprom_read,
+ .reg_write = rv3028_eeprom_write,
+ };
+
+ rv3028 = devm_kzalloc(&client->dev, sizeof(struct rv3028_data),
+ GFP_KERNEL);
+ if (!rv3028)
+ return -ENOMEM;
+
+ rv3028->regmap = devm_regmap_init_i2c(client, &regmap_config);
+
+ i2c_set_clientdata(client, rv3028);
+
+ ret = regmap_read(rv3028->regmap, RV3028_STATUS, &status);
+ if (ret < 0)
+ return ret;
+
+ if (status & RV3028_STATUS_PORF)
+ dev_warn(&client->dev, "Voltage low, data loss detected.\n");
+
+ if (status & RV3028_STATUS_AF)
+ dev_warn(&client->dev, "An alarm may have been missed.\n");
+
+ rv3028->rtc = devm_rtc_allocate_device(&client->dev);
+ if (IS_ERR(rv3028->rtc)) {
+ return PTR_ERR(rv3028->rtc);
+ }
+
+ if (client->irq > 0) {
+ ret = devm_request_threaded_irq(&client->dev, client->irq,
+ NULL, rv3028_handle_irq,
+ IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+ "rv3028", rv3028);
+ if (ret) {
+ dev_warn(&client->dev, "unable to request IRQ, alarms disabled\n");
+ client->irq = 0;
+ } else {
+ rv3028_rtc_ops.read_alarm = rv3028_get_alarm;
+ rv3028_rtc_ops.set_alarm = rv3028_set_alarm;
+ rv3028_rtc_ops.alarm_irq_enable = rv3028_alarm_irq_enable;
+ }
+ }
+
+ ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL1,
+ RV3028_CTRL1_WADA, RV3028_CTRL1_WADA);
+ if (ret)
+ return ret;
+
+ /* setup timestamping */
+ ret = regmap_update_bits(rv3028->regmap, RV3028_CTRL2,
+ RV3028_CTRL2_EIE | RV3028_CTRL2_TSE,
+ RV3028_CTRL2_EIE | RV3028_CTRL2_TSE);
+ if (ret)
+ return ret;
+
+ /* setup trickle charger */
+ if (!device_property_read_u32(&client->dev, "trickle-resistor-ohms",
+ &ohms)) {
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(rv3028_trickle_resistors); i++)
+ if (ohms == rv3028_trickle_resistors[i])
+ break;
+
+ if (i < ARRAY_SIZE(rv3028_trickle_resistors)) {
+ ret = regmap_update_bits(rv3028->regmap, RV3028_BACKUP,
+ RV3028_BACKUP_TCE |
+ RV3028_BACKUP_TCR_MASK,
+ RV3028_BACKUP_TCE | i);
+ if (ret)
+ return ret;
+ } else {
+ dev_warn(&client->dev, "invalid trickle resistor value\n");
+ }
+ }
+
+ ret = rtc_add_group(rv3028->rtc, &rv3028_attr_group);
+ if (ret)
+ return ret;
+
+ rv3028->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
+ rv3028->rtc->range_max = RTC_TIMESTAMP_END_2099;
+ rv3028->rtc->ops = &rv3028_rtc_ops;
+ ret = rtc_register_device(rv3028->rtc);
+ if (ret)
+ return ret;
+
+ nvmem_cfg.priv = rv3028->regmap;
+ rtc_nvmem_register(rv3028->rtc, &nvmem_cfg);
+ eeprom_cfg.priv = rv3028->regmap;
+ rtc_nvmem_register(rv3028->rtc, &eeprom_cfg);
+
+ rv3028->rtc->max_user_freq = 1;
+
+ return 0;
+}
+
+static const struct of_device_id rv3028_of_match[] = {
+ { .compatible = "microcrystal,rv3028", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, rv3028_of_match);
+
+static struct i2c_driver rv3028_driver = {
+ .driver = {
+ .name = "rtc-rv3028",
+ .of_match_table = of_match_ptr(rv3028_of_match),
+ },
+ .probe_new = rv3028_probe,
+};
+module_i2c_driver(rv3028_driver);
+
+MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>");
+MODULE_DESCRIPTION("Micro Crystal RV3028 RTC driver");
+MODULE_LICENSE("GPL v2");