Add driver for Sunplus SP7021
Signed-off-by: Vincent Shih <vincent.shih@xxxxxxxxxxx>
---
Changes in v2:
- Addressed the comments from Mr. Philipp Zabel
- Addressed the comments from Mr. Randy Dunlap
- Addressed the comments from Mr. Alexandre Belloni
- Sorted the files in Makefile
MAINTAINERS | 6 +
drivers/rtc/Kconfig | 11 ++
drivers/rtc/Makefile | 1 +
drivers/rtc/rtc-sunplus.c | 370 ++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 388 insertions(+)
create mode 100644 drivers/rtc/rtc-sunplus.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 3b79fd4..6c1a535 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17945,6 +17945,12 @@ L: netdev@xxxxxxxxxxxxxxx
S: Maintained
F: drivers/net/ethernet/dlink/sundance.c
+SUNPLUS RTC DRIVER
+M: Vincent Shih <vincent.shih@xxxxxxxxxxx>
+L: linux-rtc@xxxxxxxxxxxxxxx
+S: Maintained
+F: drivers/rtc/rtc-sunplus.c
+
SUPERH
M: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
M: Rich Felker <dalias@xxxxxxxx>
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index e1bc521..7ca6765 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -1028,6 +1028,17 @@ config RTC_DRV_DS1685_FAMILY
This driver can also be built as a module. If so, the module
will be called rtc-ds1685.
+config RTC_DRV_SUNPLUS
+ bool "Sunplus SP7021 RTC"
+ depends on SOC_SP7021
+ help
+ Say 'yes' to get support for Sunplus SP7021 real-time clock
+ (RTC) for industrial applications.
+
+ It provides RTC status check, timer/alarm functionalities,
+ user data reservation only with battery with voltage over 2.5V,
+ RTC power status check and battery charge.
+
choice
prompt "Subtype"
depends on RTC_DRV_DS1685_FAMILY
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 5ceeafe..93cb4b2 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -164,6 +164,7 @@ obj-$(CONFIG_RTC_DRV_STM32) += rtc-stm32.o
obj-$(CONFIG_RTC_DRV_STMP) += rtc-stmp3xxx.o
obj-$(CONFIG_RTC_DRV_SUN4V) += rtc-sun4v.o
obj-$(CONFIG_RTC_DRV_SUN6I) += rtc-sun6i.o
+obj-$(CONFIG_RTC_DRV_SUNPLUS) += rtc-sunplus.o
obj-$(CONFIG_RTC_DRV_SUNXI) += rtc-sunxi.o
obj-$(CONFIG_RTC_DRV_TEGRA) += rtc-tegra.o
obj-$(CONFIG_RTC_DRV_TEST) += rtc-test.o
diff --git a/drivers/rtc/rtc-sunplus.c b/drivers/rtc/rtc-sunplus.c
new file mode 100644
index 0000000..73c400d
--- /dev/null
+++ b/drivers/rtc/rtc-sunplus.c
@@ -0,0 +1,370 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+/* */
+/* The RTC driver for Sunplus SP7021 */
+/* */
+/* Copyright (C) 2019 Sunplus Technology Inc., All rights reseerved. */
+/* */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/ktime.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/reset.h>
+#include <linux/rtc.h>
+#include <linux/platform_device.h>
+
+#define RTC_REG_NAME "rtc_reg"
+
+#define RTC_CTRL 0x40
+#define TIMER_FREEZE (0x1 << 5)
+#define TIMER_FREEZE_MASK (1 << (5 + 16))
+#define DIS_SYS_RST_RTC (0x1 << 4)
+#define DIS_SYS_RST_RTC_MASK (1 << (4 + 16))
+#define RTC32K_MODE_RESET (0x1 << 3)
+#define RTC32K_MODE_RESET_MASK (1 << (3 + 16))
+#define ALARM_EN_OVERDUE (0x1 << 2)
+#define ALARM_EN_OVERDUE_MASK (1 << (2 + 16))
+#define ALARM_EN_PMC (0x1 << 1)
+#define ALARM_EN_PMC_MASK (1 << (1 + 16))
+#define ALARM_EN (0x1 << 0)
+#define ALARM_EN_MASK (1 << (0 + 16))
+#define RTC_TIMER_OUT 0x44
+#define RTC_DIVIDER 0x48
+#define RTC_TIMER_SET 0x4c
+#define RTC_ALARM_SET 0x50
+#define RTC_USER_DATA 0x54
+#define RTC_RESET_RECORD 0x58
+#define RTC_BATTERY_CTRL 0x5c
+#define BAT_CHARGE_RSEL_2K_OHM (0x0 << 2)
+#define BAT_CHARGE_RSEL_250_OHM (0x1 << 2)
+#define BAT_CHARGE_RSEL_50_OHM (0x2 << 2)
+#define BAT_CHARGE_RSEL_0_OHM (0x3 << 2)
+#define BAT_CHARGE_RSEL_MASK (0x3 << (2 + 16))
+#define BAT_CHARGE_DSEL_ON (0x0 << 1)
+#define BAT_CHARGE_DSEL_OFF (0x1 << 1)
+#define BAT_CHARGE_DSEL_MASK (0x1 << (1 + 16))
+#define BAT_CHARGE_EN (0x1 << 0)
+#define BAT_CHARGE_EN_MASK (0x1 << (0 + 16))
+#define RTC_TRIM_CTRL 0x60
+
+struct sunplus_rtc {
+ struct clk *rtcclk;
+ struct reset_control *rstc;
+ void __iomem *base;
+ u32 ohms;
+};
+
+struct sunplus_rtc sp_rtc;
+
+static void sp_get_seconds(unsigned long *secs)
+{
+ *secs = (unsigned long)readl(sp_rtc.base + RTC_TIMER_OUT);
+}
+
+static void sp_set_seconds(unsigned long secs)
+{
+ writel((u32)secs, sp_rtc.base + RTC_TIMER_SET);
+}
+
+static int sp_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ unsigned long secs;
+
+ sp_get_seconds(&secs);
+ rtc_time64_to_tm(secs, tm);
+ dev_dbg(dev, "%s: RTC date/time to %d-%d-%d, %02d:%02d:%02d.\r\n",
+ __func__, tm->tm_mday, tm->tm_mon + 1, tm->tm_year,
+ tm->tm_hour, tm->tm_min, tm->tm_sec);
+
+ return rtc_valid_tm(tm);
+}
+
+int sp_rtc_get_time(struct rtc_time *tm)
+{
+ unsigned long secs;
+
+ sp_get_seconds(&secs);
+ rtc_time64_to_tm(secs, tm);
+
+ return 0;
+}
+
+static int sp_rtc_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ dev_dbg(&pdev->dev, "[RTC] Debug: %s(%d)\n", __func__, __LINE__);
+
+ // Keep RTC from system reset
+ writel(DIS_SYS_RST_RTC_MASK | DIS_SYS_RST_RTC, sp_rtc.base + RTC_CTRL);
+
+ return 0;
+}
+
+static int sp_rtc_resume(struct platform_device *pdev)
+{
+ /* */
+ /* Because RTC is still powered during suspend, */
+ /* there is nothing to do here. */
+ /* */
+ dev_dbg(&pdev->dev, "[RTC] Debug: %s(%d)\n", __func__, __LINE__);
+
+ // Keep RTC from system reset
+ writel(DIS_SYS_RST_RTC_MASK | DIS_SYS_RST_RTC, sp_rtc.base + RTC_CTRL);
+
+ return 0;
+}
+
+static int sp_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ unsigned long secs;
+
+ secs = rtc_tm_to_time64(tm);
+ dev_dbg(dev, "%s, secs = %lu\n", __func__, secs);
+ sp_set_seconds(secs);
+
+ return 0;
+}
+
+static int sp_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ unsigned long alarm_time;
+
+ alarm_time = rtc_tm_to_time64(&alrm->time);
+ dev_dbg(dev, "%s, alarm_time: %u\n", __func__, (u32)(alarm_time));
+ writel((u32)alarm_time, sp_rtc.base + RTC_ALARM_SET);
+
+ return 0;
+}
+
+static int sp_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ unsigned int alarm_time;
+
+ alarm_time = readl(sp_rtc.base + RTC_ALARM_SET);
+ dev_dbg(dev, "%s, alarm_time: %u\n", __func__, alarm_time);
+
+ if (alarm_time == 0) {
+ // alarm is disabled
+ alrm->enabled = 0;
+ } else {
+ // alarm is enabled
+ alrm->enabled = 1;
+ rtc_time64_to_tm((unsigned long)(alarm_time), &alrm->time);
+ }
+
+ return 0;
+}
+
+static int sp_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+ if (enabled)
+ writel((TIMER_FREEZE_MASK | DIS_SYS_RST_RTC_MASK | RTC32K_MODE_RESET_MASK |
+ ALARM_EN_OVERDUE_MASK | ALARM_EN_PMC_MASK | ALARM_EN_MASK) |
+ (DIS_SYS_RST_RTC | ALARM_EN_OVERDUE | ALARM_EN_PMC |
+ ALARM_EN), sp_rtc.base + RTC_CTRL);
+ else
+ writel((ALARM_EN_OVERDUE_MASK | ALARM_EN_PMC_MASK | ALARM_EN_MASK) | 0x0,
+ sp_rtc.base + RTC_CTRL);
+
+ return 0;
+}
+
+static const struct rtc_class_ops sp_rtc_ops = {
+ .read_time = sp_rtc_read_time,
+ .set_time = sp_rtc_set_time,
+ .set_alarm = sp_rtc_set_alarm,
+ .read_alarm = sp_rtc_read_alarm,
+ .alarm_irq_enable = sp_rtc_alarm_irq_enable,
+};
+
+static irqreturn_t rtc_irq_handler(int irq, void *dev_id)
+{
+ struct platform_device *plat_dev = dev_id;
+ struct rtc_device *rtc = platform_get_drvdata(plat_dev);
+
+ rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF);
+ dev_dbg(&plat_dev->dev, "[RTC] ALARM INT\n");
+
+ return IRQ_HANDLED;
+}
+
+/* ---------------------------------------------------------------------------------------------- */
+/* bat_charge_rsel bat_charge_dsel bat_charge_en Remarks */
+/* x x 0 Disable */
+/* 0 0 1 0.86mA (2K Ohm with diode) */
+/* 1 0 1 1.81mA (250 Ohm with diode) */
+/* 2 0 1 2.07mA (50 Ohm with diode) */
+/* 3 0 1 16.0mA (0 Ohm with diode) */
+/* 0 1 1 1.36mA (2K Ohm without diode) */
+/* 1 1 1 3.99mA (250 Ohm without diode) */
+/* 2 1 1 4.41mA (50 Ohm without diode) */
+/* 3 1 1 16.0mA (0 Ohm without diode) */
+/* ---------------------------------------------------------------------------------------------- */
+static void sp_rtc_set_trickle_charger(struct device dev)
+{
+ int ret;
+ u32 rsel;
+
+ ret = of_property_read_u32(dev.of_node, "trickle-resistor-ohms", &sp_rtc.ohms);
+ if (ret)
+ return;
+
+ switch (sp_rtc.ohms) {
+ case 2000:
+ rsel = BAT_CHARGE_RSEL_2K_OHM;
+ break;
+ case 250:
+ rsel = BAT_CHARGE_RSEL_250_OHM;
+ break;
+ case 50:
+ rsel = BAT_CHARGE_RSEL_50_OHM;
+ break;
+ case 0:
+ rsel = BAT_CHARGE_RSEL_0_OHM;
+ break;
+ default:
+ return;
+ }
+
+ writel(BAT_CHARGE_RSEL_MASK | rsel, sp_rtc.base + RTC_BATTERY_CTRL);
+
+ ret = of_property_read_bool(dev.of_node, "trickle-diode-disable");
+ if (ret)
+ writel(BAT_CHARGE_DSEL_MASK | BAT_CHARGE_DSEL_OFF, sp_rtc.base + RTC_BATTERY_CTRL);
+ else
+ writel(BAT_CHARGE_DSEL_MASK | BAT_CHARGE_DSEL_ON, sp_rtc.base + RTC_BATTERY_CTRL);
+
+ writel(BAT_CHARGE_EN_MASK | BAT_CHARGE_EN, sp_rtc.base + RTC_BATTERY_CTRL);
+}
+
+static int sp_rtc_probe(struct platform_device *plat_dev)
+{
+ struct rtc_device *rtc;
+ struct resource *res;
+ const struct rtc_class_ops *rtc_ops;
+ void __iomem *reg_base;
+ int ret, irq;
+
+ memset(&sp_rtc, 0, sizeof(sp_rtc));
+
+ // find and map our resources
+ res = platform_get_resource_byname(plat_dev, IORESOURCE_MEM, RTC_REG_NAME);
+
+ if (res) {
+ dev_dbg(&plat_dev->dev, "res = 0x%x\n", res->start);
+
+ reg_base = devm_ioremap_resource(&plat_dev->dev, res);
+ if (IS_ERR(reg_base)) {
+ dev_err(&plat_dev->dev, "%s devm_ioremap_resource fail\n", RTC_REG_NAME);
+ return PTR_ERR(reg_base);
+ }
+
+ dev_dbg(&plat_dev->dev, "reg_base = 0x%lx\n", (unsigned long)reg_base);
+ }
+
+ sp_rtc.base = reg_base;
+ rtc_ops = &sp_rtc_ops;
+
+ // Keep RTC from system reset
+ writel(DIS_SYS_RST_RTC_MASK | DIS_SYS_RST_RTC, sp_rtc.base + RTC_CTRL);
+
+ // request irq
+ irq = platform_get_irq(plat_dev, 0);
+ if (irq < 0) {
+ dev_err(&plat_dev->dev, "platform_get_irq failed\n");
+ irq = IRQ_NOTCONNECTED;
+ }
+
+ ret = devm_request_irq(&plat_dev->dev, irq, rtc_irq_handler,
+ IRQF_TRIGGER_RISING, "rtc irq", plat_dev);
+ if (ret) {
+ dev_err(&plat_dev->dev, "devm_request_irq failed: %d\n", ret);
+ return ret;
+ }
+
+ // Setup trickle charger
+ if (plat_dev->dev.of_node)
+ sp_rtc_set_trickle_charger(plat_dev->dev);
+
+ // reset
+ sp_rtc.rstc = devm_reset_control_get_exclusive(&plat_dev->dev, NULL);
+ if (IS_ERR(sp_rtc.rstc)) {
+ ret = dev_err_probe(&plat_dev->dev, PTR_ERR(sp_rtc.rstc),
+ "failed to retrieve reset controller\n");
+ return PTR_ERR(sp_rtc.rstc);
+ }
+
+ // clk
+ sp_rtc.rtcclk = devm_clk_get(&plat_dev->dev, NULL);
+ if (IS_ERR(sp_rtc.rtcclk)) {
+ dev_err(&plat_dev->dev, "devm_clk_get fail\n");
+ return PTR_ERR(sp_rtc.rtcclk);
+ }
+
+ ret = reset_control_deassert(sp_rtc.rstc);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(sp_rtc.rtcclk);
+ if (ret)
+ return ret;
+
+ device_init_wakeup(&plat_dev->dev, 1);
+
+ rtc = devm_rtc_allocate_device(&plat_dev->dev);
+ if (IS_ERR(rtc))
+ return PTR_ERR(rtc);
+
+ rtc->range_max = U32_MAX;
+ rtc->range_min = 0;
+ rtc->ops = rtc_ops;
+
+ ret = devm_rtc_register_device(rtc);
+ if (ret)
+ goto free_reset_assert_clk;
+
+ platform_set_drvdata(plat_dev, rtc);
+ dev_info(&plat_dev->dev, "sp7021-rtc loaded\n");
+
+ return 0;
+
+free_reset_assert_clk:
+ reset_control_assert(sp_rtc.rstc);
+ clk_disable_unprepare(sp_rtc.rtcclk);
+
+ return ret;
+}
+
+static int sp_rtc_remove(struct platform_device *plat_dev)
+{
+ reset_control_assert(sp_rtc.rstc);
+ clk_disable_unprepare(sp_rtc.rtcclk);
+
+ return 0;
+}
+
+static const struct of_device_id sp_rtc_of_match[] = {
+ { .compatible = "sunplus,sp7021-rtc" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, sp_rtc_of_match);
+
+static struct platform_driver sp_rtc_driver = {
+ .probe = sp_rtc_probe,
+ .remove = sp_rtc_remove,
+ .suspend = sp_rtc_suspend,
+ .resume = sp_rtc_resume,
+ .driver = {
+ .name = "sp7021-rtc",
+ .owner = THIS_MODULE,
+ .of_match_table = sp_rtc_of_match,
+ },
+};
+module_platform_driver(sp_rtc_driver);
+
+MODULE_AUTHOR("Vincent Shih <vincent.shih@xxxxxxxxxxx>");
+MODULE_DESCRIPTION("Sunplus RTC driver");
+MODULE_LICENSE("GPL v2");
+
--
2.7.4
