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path: root/drivers/rtc/rtc-tps6586x.c
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Diffstat (limited to 'drivers/rtc/rtc-tps6586x.c')
-rw-r--r--drivers/rtc/rtc-tps6586x.c327
1 files changed, 327 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-tps6586x.c b/drivers/rtc/rtc-tps6586x.c
new file mode 100644
index 0000000000..20faf08c25
--- /dev/null
+++ b/drivers/rtc/rtc-tps6586x.c
@@ -0,0 +1,327 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * rtc-tps6586x.c: RTC driver for TI PMIC TPS6586X
+ *
+ * Copyright (c) 2012, NVIDIA Corporation.
+ *
+ * Author: Laxman Dewangan <ldewangan@nvidia.com>
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/mfd/tps6586x.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/rtc.h>
+#include <linux/slab.h>
+
+#define RTC_CTRL 0xc0
+#define POR_RESET_N BIT(7)
+#define OSC_SRC_SEL BIT(6)
+#define RTC_ENABLE BIT(5) /* enables alarm */
+#define RTC_BUF_ENABLE BIT(4) /* 32 KHz buffer enable */
+#define PRE_BYPASS BIT(3) /* 0=1KHz or 1=32KHz updates */
+#define CL_SEL_MASK (BIT(2)|BIT(1))
+#define CL_SEL_POS 1
+#define RTC_ALARM1_HI 0xc1
+#define RTC_COUNT4 0xc6
+
+/* start a PMU RTC access by reading the register prior to the RTC_COUNT4 */
+#define RTC_COUNT4_DUMMYREAD 0xc5
+
+/*only 14-bits width in second*/
+#define ALM1_VALID_RANGE_IN_SEC 0x3FFF
+
+#define TPS6586X_RTC_CL_SEL_1_5PF 0x0
+#define TPS6586X_RTC_CL_SEL_6_5PF 0x1
+#define TPS6586X_RTC_CL_SEL_7_5PF 0x2
+#define TPS6586X_RTC_CL_SEL_12_5PF 0x3
+
+struct tps6586x_rtc {
+ struct device *dev;
+ struct rtc_device *rtc;
+ int irq;
+ bool irq_en;
+};
+
+static inline struct device *to_tps6586x_dev(struct device *dev)
+{
+ return dev->parent;
+}
+
+static int tps6586x_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct device *tps_dev = to_tps6586x_dev(dev);
+ unsigned long long ticks = 0;
+ time64_t seconds;
+ u8 buff[6];
+ int ret;
+ int i;
+
+ ret = tps6586x_reads(tps_dev, RTC_COUNT4_DUMMYREAD, sizeof(buff), buff);
+ if (ret < 0) {
+ dev_err(dev, "read counter failed with err %d\n", ret);
+ return ret;
+ }
+
+ for (i = 1; i < sizeof(buff); i++) {
+ ticks <<= 8;
+ ticks |= buff[i];
+ }
+
+ seconds = ticks >> 10;
+ rtc_time64_to_tm(seconds, tm);
+
+ return 0;
+}
+
+static int tps6586x_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct device *tps_dev = to_tps6586x_dev(dev);
+ unsigned long long ticks;
+ time64_t seconds;
+ u8 buff[5];
+ int ret;
+
+ seconds = rtc_tm_to_time64(tm);
+
+ ticks = (unsigned long long)seconds << 10;
+ buff[0] = (ticks >> 32) & 0xff;
+ buff[1] = (ticks >> 24) & 0xff;
+ buff[2] = (ticks >> 16) & 0xff;
+ buff[3] = (ticks >> 8) & 0xff;
+ buff[4] = ticks & 0xff;
+
+ /* Disable RTC before changing time */
+ ret = tps6586x_clr_bits(tps_dev, RTC_CTRL, RTC_ENABLE);
+ if (ret < 0) {
+ dev_err(dev, "failed to clear RTC_ENABLE\n");
+ return ret;
+ }
+
+ ret = tps6586x_writes(tps_dev, RTC_COUNT4, sizeof(buff), buff);
+ if (ret < 0) {
+ dev_err(dev, "failed to program new time\n");
+ return ret;
+ }
+
+ /* Enable RTC */
+ ret = tps6586x_set_bits(tps_dev, RTC_CTRL, RTC_ENABLE);
+ if (ret < 0) {
+ dev_err(dev, "failed to set RTC_ENABLE\n");
+ return ret;
+ }
+ return 0;
+}
+
+static int tps6586x_rtc_alarm_irq_enable(struct device *dev,
+ unsigned int enabled)
+{
+ struct tps6586x_rtc *rtc = dev_get_drvdata(dev);
+
+ if (enabled && !rtc->irq_en) {
+ enable_irq(rtc->irq);
+ rtc->irq_en = true;
+ } else if (!enabled && rtc->irq_en) {
+ disable_irq(rtc->irq);
+ rtc->irq_en = false;
+ }
+ return 0;
+}
+
+static int tps6586x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct device *tps_dev = to_tps6586x_dev(dev);
+ time64_t seconds;
+ unsigned long ticks;
+ unsigned long rtc_current_time;
+ unsigned long long rticks = 0;
+ u8 buff[3];
+ u8 rbuff[6];
+ int ret;
+ int i;
+
+ seconds = rtc_tm_to_time64(&alrm->time);
+
+ ret = tps6586x_rtc_alarm_irq_enable(dev, alrm->enabled);
+ if (ret < 0) {
+ dev_err(dev, "can't set alarm irq, err %d\n", ret);
+ return ret;
+ }
+
+ ret = tps6586x_reads(tps_dev, RTC_COUNT4_DUMMYREAD,
+ sizeof(rbuff), rbuff);
+ if (ret < 0) {
+ dev_err(dev, "read counter failed with err %d\n", ret);
+ return ret;
+ }
+
+ for (i = 1; i < sizeof(rbuff); i++) {
+ rticks <<= 8;
+ rticks |= rbuff[i];
+ }
+
+ rtc_current_time = rticks >> 10;
+ if ((seconds - rtc_current_time) > ALM1_VALID_RANGE_IN_SEC)
+ seconds = rtc_current_time - 1;
+
+ ticks = (unsigned long long)seconds << 10;
+ buff[0] = (ticks >> 16) & 0xff;
+ buff[1] = (ticks >> 8) & 0xff;
+ buff[2] = ticks & 0xff;
+
+ ret = tps6586x_writes(tps_dev, RTC_ALARM1_HI, sizeof(buff), buff);
+ if (ret)
+ dev_err(dev, "programming alarm failed with err %d\n", ret);
+
+ return ret;
+}
+
+static int tps6586x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct device *tps_dev = to_tps6586x_dev(dev);
+ unsigned long ticks;
+ time64_t seconds;
+ u8 buff[3];
+ int ret;
+
+ ret = tps6586x_reads(tps_dev, RTC_ALARM1_HI, sizeof(buff), buff);
+ if (ret) {
+ dev_err(dev, "read RTC_ALARM1_HI failed with err %d\n", ret);
+ return ret;
+ }
+
+ ticks = (buff[0] << 16) | (buff[1] << 8) | buff[2];
+ seconds = ticks >> 10;
+
+ rtc_time64_to_tm(seconds, &alrm->time);
+ return 0;
+}
+
+static const struct rtc_class_ops tps6586x_rtc_ops = {
+ .read_time = tps6586x_rtc_read_time,
+ .set_time = tps6586x_rtc_set_time,
+ .set_alarm = tps6586x_rtc_set_alarm,
+ .read_alarm = tps6586x_rtc_read_alarm,
+ .alarm_irq_enable = tps6586x_rtc_alarm_irq_enable,
+};
+
+static irqreturn_t tps6586x_rtc_irq(int irq, void *data)
+{
+ struct tps6586x_rtc *rtc = data;
+
+ rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);
+ return IRQ_HANDLED;
+}
+
+static int tps6586x_rtc_probe(struct platform_device *pdev)
+{
+ struct device *tps_dev = to_tps6586x_dev(&pdev->dev);
+ struct tps6586x_rtc *rtc;
+ int ret;
+
+ rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
+ if (!rtc)
+ return -ENOMEM;
+
+ rtc->dev = &pdev->dev;
+ rtc->irq = platform_get_irq(pdev, 0);
+
+ /* 1 kHz tick mode, enable tick counting */
+ ret = tps6586x_update(tps_dev, RTC_CTRL,
+ RTC_ENABLE | OSC_SRC_SEL |
+ ((TPS6586X_RTC_CL_SEL_1_5PF << CL_SEL_POS) & CL_SEL_MASK),
+ RTC_ENABLE | OSC_SRC_SEL | PRE_BYPASS | CL_SEL_MASK);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "unable to start counter\n");
+ return ret;
+ }
+
+ device_init_wakeup(&pdev->dev, 1);
+
+ platform_set_drvdata(pdev, rtc);
+ rtc->rtc = devm_rtc_allocate_device(&pdev->dev);
+ if (IS_ERR(rtc->rtc)) {
+ ret = PTR_ERR(rtc->rtc);
+ goto fail_rtc_register;
+ }
+
+ rtc->rtc->ops = &tps6586x_rtc_ops;
+ rtc->rtc->range_max = (1ULL << 30) - 1; /* 30-bit seconds */
+ rtc->rtc->alarm_offset_max = ALM1_VALID_RANGE_IN_SEC;
+ rtc->rtc->start_secs = mktime64(2009, 1, 1, 0, 0, 0);
+ rtc->rtc->set_start_time = true;
+
+ irq_set_status_flags(rtc->irq, IRQ_NOAUTOEN);
+
+ ret = devm_request_threaded_irq(&pdev->dev, rtc->irq, NULL,
+ tps6586x_rtc_irq,
+ IRQF_ONESHOT,
+ dev_name(&pdev->dev), rtc);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "request IRQ(%d) failed with ret %d\n",
+ rtc->irq, ret);
+ goto fail_rtc_register;
+ }
+
+ ret = devm_rtc_register_device(rtc->rtc);
+ if (ret)
+ goto fail_rtc_register;
+
+ return 0;
+
+fail_rtc_register:
+ tps6586x_update(tps_dev, RTC_CTRL, 0,
+ RTC_ENABLE | OSC_SRC_SEL | PRE_BYPASS | CL_SEL_MASK);
+ return ret;
+};
+
+static void tps6586x_rtc_remove(struct platform_device *pdev)
+{
+ struct device *tps_dev = to_tps6586x_dev(&pdev->dev);
+
+ tps6586x_update(tps_dev, RTC_CTRL, 0,
+ RTC_ENABLE | OSC_SRC_SEL | PRE_BYPASS | CL_SEL_MASK);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int tps6586x_rtc_suspend(struct device *dev)
+{
+ struct tps6586x_rtc *rtc = dev_get_drvdata(dev);
+
+ if (device_may_wakeup(dev))
+ enable_irq_wake(rtc->irq);
+ return 0;
+}
+
+static int tps6586x_rtc_resume(struct device *dev)
+{
+ struct tps6586x_rtc *rtc = dev_get_drvdata(dev);
+
+ if (device_may_wakeup(dev))
+ disable_irq_wake(rtc->irq);
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(tps6586x_pm_ops, tps6586x_rtc_suspend,
+ tps6586x_rtc_resume);
+
+static struct platform_driver tps6586x_rtc_driver = {
+ .driver = {
+ .name = "tps6586x-rtc",
+ .pm = &tps6586x_pm_ops,
+ },
+ .probe = tps6586x_rtc_probe,
+ .remove_new = tps6586x_rtc_remove,
+};
+module_platform_driver(tps6586x_rtc_driver);
+
+MODULE_ALIAS("platform:tps6586x-rtc");
+MODULE_DESCRIPTION("TI TPS6586x RTC driver");
+MODULE_AUTHOR("Laxman dewangan <ldewangan@nvidia.com>");
+MODULE_LICENSE("GPL v2");
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-15 09:16:15 +0000