This adds support for EPSON TOYOCOM RTC-7301SF/DG which has parallel
interface compatible with SRAM.
This driver supports basic clock, calendar and alarm functionality.
Tested with Microblaze linux running on Artix7 FPGA board with my own
custom IP for RTC-7301.
Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx>
Acked-by: Rob Herring <robh@xxxxxxxxxx>
Cc: Alessandro Zummo <a.zummo@xxxxxxxxxxxx>
Cc: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
---
* Changes from v1
- Add interrupt-parent property in the DT example
- Fix typo for RTC7301_TIMER_CONTROL_* register bit field names
- Don't forcibly disable alarm in the initialization
.../devicetree/bindings/rtc/epson,rtc7301.txt | 16 +
drivers/rtc/Kconfig | 11 +
drivers/rtc/Makefile | 1 +
drivers/rtc/rtc-r7301.c | 455 +++++++++++++++++++++
4 files changed, 483 insertions(+)
create mode 100644 Documentation/devicetree/bindings/rtc/epson,rtc7301.txt
create mode 100644 drivers/rtc/rtc-r7301.c
diff --git a/Documentation/devicetree/bindings/rtc/epson,rtc7301.txt b/Documentation/devicetree/bindings/rtc/epson,rtc7301.txt
new file mode 100644
index 0000000..5f9df3f
--- /dev/null
+++ b/Documentation/devicetree/bindings/rtc/epson,rtc7301.txt
@@ -0,0 +1,16 @@
+EPSON TOYOCOM RTC-7301SF/DG
+
+Required properties:
+
+- compatible: Should be "epson,rtc7301sf" or "epson,rtc7301dg"
+- reg: Specifies base physical address and size of the registers.
+- interrupts: A single interrupt specifier.
+
+Example:
+
+rtc: rtc@44a00000 {
+ compatible = "epson,rtc7301dg";
+ reg = <0x44a00000 0x10000>;
+ interrupt-parent = <&axi_intc_0>;
+ interrupts = <3 2>;
+};
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 0a5e058..b8f1f9c 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -1705,6 +1705,17 @@ config RTC_DRV_PIC32
This driver can also be built as a module. If so, the module
will be called rtc-pic32
+config RTC_DRV_R7301
+ tristate "EPSON TOYOCOM RTC-7301SF/DG"
+ select REGMAP_MMIO
+ depends on OF && HAS_IOMEM
+ help
+ If you say yes here you get support for the EPSON TOYOCOM
+ RTC-7301SF/DG chips.
+
+ This driver can also be built as a module. If so, the module
+ will be called rtc-r7301.
+
comment "HID Sensor RTC drivers"
config RTC_DRV_HID_SENSOR_TIME
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 1ac694a..f13ab1c 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -120,6 +120,7 @@ obj-$(CONFIG_RTC_DRV_PM8XXX) += rtc-pm8xxx.o
obj-$(CONFIG_RTC_DRV_PS3) += rtc-ps3.o
obj-$(CONFIG_RTC_DRV_PUV3) += rtc-puv3.o
obj-$(CONFIG_RTC_DRV_PXA) += rtc-pxa.o
+obj-$(CONFIG_RTC_DRV_R7301) += rtc-r7301.o
obj-$(CONFIG_RTC_DRV_R9701) += rtc-r9701.o
obj-$(CONFIG_RTC_DRV_RC5T583) += rtc-rc5t583.o
obj-$(CONFIG_RTC_DRV_RK808) += rtc-rk808.o
diff --git a/drivers/rtc/rtc-r7301.c b/drivers/rtc/rtc-r7301.c
new file mode 100644
index 0000000..0929f10
--- /dev/null
+++ b/drivers/rtc/rtc-r7301.c
@@ -0,0 +1,455 @@
+/*
+ * EPSON TOYOCOM RTC-7301SF/DG Driver
+ *
+ * Copyright (c) 2016 Akinobu Mita <akinobu.mita@xxxxxxxxx>
+ *
+ * Based on rtc-rp5c01.c
+ *
+ * Datasheet: http://www5.epsondevice.com/en/products/parallel/rtc7301sf.html
+ */
+
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/regmap.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+
+#define DRV_NAME "rtc-r7301"
+
+enum {
+ RTC7301_1_SEC = 0x0, /* Bank 0 and Band 1 */
+ RTC7301_10_SEC = 0x1, /* Bank 0 and Band 1 */
+ RTC7301_AE = BIT(3),
+ RTC7301_1_MIN = 0x2, /* Bank 0 and Band 1 */
+ RTC7301_10_MIN = 0x3, /* Bank 0 and Band 1 */
+ RTC7301_1_HOUR = 0x4, /* Bank 0 and Band 1 */
+ RTC7301_10_HOUR = 0x5, /* Bank 0 and Band 1 */
+ RTC7301_DAY_OF_WEEK = 0x6, /* Bank 0 and Band 1 */
+ RTC7301_1_DAY = 0x7, /* Bank 0 and Band 1 */
+ RTC7301_10_DAY = 0x8, /* Bank 0 and Band 1 */
+ RTC7301_1_MONTH = 0x9, /* Bank 0 */
+ RTC7301_10_MONTH = 0xa, /* Bank 0 */
+ RTC7301_1_YEAR = 0xb, /* Bank 0 */
+ RTC7301_10_YEAR = 0xc, /* Bank 0 */
+ RTC7301_100_YEAR = 0xd, /* Bank 0 */
+ RTC7301_1000_YEAR = 0xe, /* Bank 0 */
+ RTC7301_ALARM_CONTROL = 0xe, /* Bank 1 */
+ RTC7301_ALARM_CONTROL_AIE = BIT(0),
+ RTC7301_ALARM_CONTROL_AF = BIT(1),
+ RTC7301_TIMER_CONTROL = 0xe, /* Bank 2 */
+ RTC7301_TIMER_CONTROL_TIE = BIT(0),
+ RTC7301_TIMER_CONTROL_TF = BIT(1),
+ RTC7301_CONTROL = 0xf, /* All banks */
+ RTC7301_CONTROL_BUSY = BIT(0),
+ RTC7301_CONTROL_STOP = BIT(1),
+ RTC7301_CONTROL_BANK_SEL_0 = BIT(2),
+ RTC7301_CONTROL_BANK_SEL_1 = BIT(3),
+};
+
+struct rtc7301_priv {
+ struct regmap *regmap;
+ int irq;
+ spinlock_t lock;
+ u8 bank;
+};
+
+static const struct regmap_config rtc7301_regmap_config = {
+ .reg_bits = 32,
+ .val_bits = 8,
+ .reg_stride = 4,
+};
+
+static u8 rtc7301_read(struct rtc7301_priv *priv, unsigned int reg)
+{
+ int reg_stride = regmap_get_reg_stride(priv->regmap);
+ unsigned int val;
+
+ regmap_read(priv->regmap, reg_stride * reg, &val);
+
+ return val & 0xf;
+}
+
+static void rtc7301_write(struct rtc7301_priv *priv, u8 val, unsigned int reg)
+{
+ int reg_stride = regmap_get_reg_stride(priv->regmap);
+
+ regmap_write(priv->regmap, reg_stride * reg, val);
+}
+
+static void rtc7301_update_bits(struct rtc7301_priv *priv, unsigned int reg,
+ u8 mask, u8 val)
+{
+ int reg_stride = regmap_get_reg_stride(priv->regmap);
+
+ regmap_update_bits(priv->regmap, reg_stride * reg, mask, val);
+}
+
+static int rtc7301_wait_while_busy(struct rtc7301_priv *priv)
+{
+ int retries = 100;
+
+ while (retries-- > 0) {
+ u8 val;
+
+ val = rtc7301_read(priv, RTC7301_CONTROL);
+ if (!(val & RTC7301_CONTROL_BUSY))
+ return 0;
+
+ usleep_range(200, 300);
+ }
+
+ return -ETIMEDOUT;
+}
+
+static void rtc7301_stop(struct rtc7301_priv *priv)
+{
+ rtc7301_update_bits(priv, RTC7301_CONTROL, RTC7301_CONTROL_STOP,
+ RTC7301_CONTROL_STOP);
+}
+
+static void rtc7301_start(struct rtc7301_priv *priv)
+{
+ rtc7301_update_bits(priv, RTC7301_CONTROL, RTC7301_CONTROL_STOP, 0);
+}
+
+static void rtc7301_select_bank(struct rtc7301_priv *priv, u8 bank)
+{
+ u8 val = 0;
+
+ if (bank == priv->bank)
+ return;
+
+ if (bank & BIT(0))
+ val |= RTC7301_CONTROL_BANK_SEL_0;
+ if (bank & BIT(1))
+ val |= RTC7301_CONTROL_BANK_SEL_1;
+
+ rtc7301_update_bits(priv, RTC7301_CONTROL,
+ RTC7301_CONTROL_BANK_SEL_0 |
+ RTC7301_CONTROL_BANK_SEL_1, val);
+
+ priv->bank = bank;
+}
+
+static void rtc7301_get_time(struct rtc7301_priv *priv, struct rtc_time *tm,
+ bool alarm)
+{
+ int year;
+
+ tm->tm_sec = rtc7301_read(priv, RTC7301_1_SEC);
+ tm->tm_sec += (rtc7301_read(priv, RTC7301_10_SEC) & ~RTC7301_AE) * 10;
+ tm->tm_min = rtc7301_read(priv, RTC7301_1_MIN);
+ tm->tm_min += (rtc7301_read(priv, RTC7301_10_MIN) & ~RTC7301_AE) * 10;
+ tm->tm_hour = rtc7301_read(priv, RTC7301_1_HOUR);
+ tm->tm_hour += (rtc7301_read(priv, RTC7301_10_HOUR) & ~RTC7301_AE) * 10;
+ tm->tm_mday = rtc7301_read(priv, RTC7301_1_DAY);
+ tm->tm_mday += (rtc7301_read(priv, RTC7301_10_DAY) & ~RTC7301_AE) * 10;
+
+ if (alarm) {
+ tm->tm_wday = -1;
+ tm->tm_mon = -1;
+ tm->tm_year = -1;
+ tm->tm_yday = -1;
+ tm->tm_isdst = -1;
+ return;
+ }
+
+ tm->tm_wday = (rtc7301_read(priv, RTC7301_DAY_OF_WEEK) & ~RTC7301_AE);
+ tm->tm_mon = rtc7301_read(priv, RTC7301_10_MONTH) * 10 +
+ rtc7301_read(priv, RTC7301_1_MONTH) - 1;
+ year = rtc7301_read(priv, RTC7301_1000_YEAR) * 1000 +
+ rtc7301_read(priv, RTC7301_100_YEAR) * 100 +
+ rtc7301_read(priv, RTC7301_10_YEAR) * 10 +
+ rtc7301_read(priv, RTC7301_1_YEAR);
+
+ tm->tm_year = year - 1900;
+}
+
+static void rtc7301_write_time(struct rtc7301_priv *priv, struct rtc_time *tm,
+ bool alarm)
+{
+ int year;
+
+ rtc7301_write(priv, tm->tm_sec % 10, RTC7301_1_SEC);
+ rtc7301_write(priv, tm->tm_sec / 10, RTC7301_10_SEC);
+
+ rtc7301_write(priv, tm->tm_min % 10, RTC7301_1_MIN);
+ rtc7301_write(priv, tm->tm_min / 10, RTC7301_10_MIN);
+
+ rtc7301_write(priv, tm->tm_hour % 10, RTC7301_1_HOUR);
+ rtc7301_write(priv, tm->tm_hour / 10, RTC7301_10_HOUR);
+
+ rtc7301_write(priv, tm->tm_mday % 10, RTC7301_1_DAY);
+ rtc7301_write(priv, tm->tm_mday / 10, RTC7301_10_DAY);
+
+ /* Don't care for alarm register */
+ rtc7301_write(priv, alarm ? RTC7301_AE : tm->tm_wday,
+ RTC7301_DAY_OF_WEEK);
+
+ if (alarm)
+ return;
+
+ rtc7301_write(priv, (tm->tm_mon + 1) % 10, RTC7301_1_MONTH);
+ rtc7301_write(priv, (tm->tm_mon + 1) / 10, RTC7301_10_MONTH);
+
+ year = tm->tm_year + 1900;
+
+ rtc7301_write(priv, year % 10, RTC7301_1_YEAR);
+ rtc7301_write(priv, (year / 10) % 10, RTC7301_10_YEAR);
+ rtc7301_write(priv, (year / 100) % 10, RTC7301_100_YEAR);
+ rtc7301_write(priv, year / 1000, RTC7301_1000_YEAR);
+}
+
+static void rtc7301_alarm_irq(struct rtc7301_priv *priv, unsigned int enabled)
+{
+ rtc7301_update_bits(priv, RTC7301_ALARM_CONTROL,
+ RTC7301_ALARM_CONTROL_AF |
+ RTC7301_ALARM_CONTROL_AIE,
+ enabled ? RTC7301_ALARM_CONTROL_AIE : 0);
+}
+
+static int rtc7301_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct rtc7301_priv *priv = dev_get_drvdata(dev);
+ unsigned long flags;
+ int err;
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ rtc7301_select_bank(priv, 0);
+
+ err = rtc7301_wait_while_busy(priv);
+ if (!err)
+ rtc7301_get_time(priv, tm, false);
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return err ? err : rtc_valid_tm(tm);
+}
+
+static int rtc7301_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct rtc7301_priv *priv = dev_get_drvdata(dev);
+ unsigned long flags;
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ rtc7301_stop(priv);
+ usleep_range(200, 300);
+ rtc7301_select_bank(priv, 0);
+ rtc7301_write_time(priv, tm, false);
+ rtc7301_start(priv);
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+static int rtc7301_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ struct rtc7301_priv *priv = dev_get_drvdata(dev);
+ unsigned long flags;
+ u8 alrm_ctrl;
+
+ if (priv->irq <= 0)
+ return -EINVAL;
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ rtc7301_select_bank(priv, 1);
+ rtc7301_get_time(priv, &alarm->time, true);
+
+ alrm_ctrl = rtc7301_read(priv, RTC7301_ALARM_CONTROL);
+
+ alarm->enabled = !!(alrm_ctrl & RTC7301_ALARM_CONTROL_AIE);
+ alarm->pending = !!(alrm_ctrl & RTC7301_ALARM_CONTROL_AF);
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+static int rtc7301_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ struct rtc7301_priv *priv = dev_get_drvdata(dev);
+ unsigned long flags;
+
+ if (priv->irq <= 0)
+ return -EINVAL;
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ rtc7301_select_bank(priv, 1);
+ rtc7301_write_time(priv, &alarm->time, true);
+ rtc7301_alarm_irq(priv, alarm->enabled);
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+static int rtc7301_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+ struct rtc7301_priv *priv = dev_get_drvdata(dev);
+ unsigned long flags;
+
+ if (priv->irq <= 0)
+ return -EINVAL;
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ rtc7301_select_bank(priv, 1);
+ rtc7301_alarm_irq(priv, enabled);
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+static const struct rtc_class_ops rtc7301_rtc_ops = {
+ .read_time = rtc7301_read_time,
+ .set_time = rtc7301_set_time,
+ .read_alarm = rtc7301_read_alarm,
+ .set_alarm = rtc7301_set_alarm,
+ .alarm_irq_enable = rtc7301_alarm_irq_enable,
+};
+
+static irqreturn_t rtc7301_irq_handler(int irq, void *dev_id)
+{
+ struct rtc_device *rtc = dev_id;
+ struct rtc7301_priv *priv = dev_get_drvdata(rtc->dev.parent);
+ unsigned long flags;
+ irqreturn_t ret = IRQ_NONE;
+ u8 alrm_ctrl;
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ rtc7301_select_bank(priv, 1);
+
+ alrm_ctrl = rtc7301_read(priv, RTC7301_ALARM_CONTROL);
+ if (alrm_ctrl & RTC7301_ALARM_CONTROL_AF) {
+ ret = IRQ_HANDLED;
+ rtc7301_alarm_irq(priv, false);
+ rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF);
+ }
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return ret;
+}
+
+static void rtc7301_init(struct rtc7301_priv *priv)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ rtc7301_select_bank(priv, 2);
+ rtc7301_write(priv, 0, RTC7301_TIMER_CONTROL);
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+static int __init rtc7301_rtc_probe(struct platform_device *dev)
+{
+ struct resource *res;
+ void __iomem *regs;
+ struct rtc7301_priv *priv;
+ struct rtc_device *rtc;
+ int ret;
+
+ res = platform_get_resource(dev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+
+ priv = devm_kzalloc(&dev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ regs = devm_ioremap_resource(&dev->dev, res);
+ if (IS_ERR(regs))
+ return PTR_ERR(regs);
+
+ priv->regmap = devm_regmap_init_mmio(&dev->dev, regs,
+ &rtc7301_regmap_config);
+ if (IS_ERR(priv->regmap))
+ return PTR_ERR(priv->regmap);
+
+ priv->irq = platform_get_irq(dev, 0);
+
+ spin_lock_init(&priv->lock);
+ priv->bank = -1;
+
+ rtc7301_init(priv);
+
+ platform_set_drvdata(dev, priv);
+
+ rtc = devm_rtc_device_register(&dev->dev, DRV_NAME, &rtc7301_rtc_ops,
+ THIS_MODULE);
+ if (IS_ERR(rtc))
+ return PTR_ERR(rtc);
+
+ if (priv->irq > 0) {
+ ret = devm_request_irq(&dev->dev, priv->irq,
+ rtc7301_irq_handler, IRQF_SHARED,
+ dev_name(&dev->dev), rtc);
+ if (ret) {
+ priv->irq = 0;
+ dev_err(&dev->dev, "unable to request IRQ\n");
+ } else {
+ device_set_wakeup_capable(&dev->dev, true);
+ }
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+
+static int rtc7301_suspend(struct device *dev)
+{
+ struct rtc7301_priv *priv = dev_get_drvdata(dev);
+
+ if (device_may_wakeup(dev))
+ enable_irq_wake(priv->irq);
+
+ return 0;
+}
+
+static int rtc7301_resume(struct device *dev)
+{
+ struct rtc7301_priv *priv = dev_get_drvdata(dev);
+
+ if (device_may_wakeup(dev))
+ disable_irq_wake(priv->irq);
+
+ return 0;
+}
+
+#endif
+
+static SIMPLE_DEV_PM_OPS(rtc7301_pm_ops, rtc7301_suspend, rtc7301_resume);
+
+static const struct of_device_id rtc7301_dt_match[] = {
+ { .compatible = "epson,rtc7301sf" },
+ { .compatible = "epson,rtc7301dg" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, rtc7301_dt_match);
+
+static struct platform_driver rtc7301_rtc_driver = {
+ .driver = {
+ .name = DRV_NAME,
+ .of_match_table = rtc7301_dt_match,
+ .pm = &rtc7301_pm_ops,
+ },
+};
+
+module_platform_driver_probe(rtc7301_rtc_driver, rtc7301_rtc_probe);
+
+MODULE_AUTHOR("Akinobu Mita <akinobu.mita@xxxxxxxxx>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("EPSON TOYOCOM RTC-7301SF/DG Driver");
+MODULE_ALIAS("platform:rtc-r7301");
--
2.7.4
--
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