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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/rtc/rtc-wm8350.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'drivers/rtc/rtc-wm8350.c')
-rw-r--r--drivers/rtc/rtc-wm8350.c474
1 files changed, 474 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-wm8350.c b/drivers/rtc/rtc-wm8350.c
new file mode 100644
index 000000000..3bd60d067
--- /dev/null
+++ b/drivers/rtc/rtc-wm8350.c
@@ -0,0 +1,474 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Real Time Clock driver for Wolfson Microelectronics WM8350
+ *
+ * Copyright (C) 2007, 2008 Wolfson Microelectronics PLC.
+ *
+ * Author: Liam Girdwood
+ * linux@wolfsonmicro.com
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/time.h>
+#include <linux/rtc.h>
+#include <linux/bcd.h>
+#include <linux/interrupt.h>
+#include <linux/ioctl.h>
+#include <linux/completion.h>
+#include <linux/mfd/wm8350/rtc.h>
+#include <linux/mfd/wm8350/core.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+
+#define WM8350_SET_ALM_RETRIES 5
+#define WM8350_SET_TIME_RETRIES 5
+#define WM8350_GET_TIME_RETRIES 5
+
+/*
+ * Read current time and date in RTC
+ */
+static int wm8350_rtc_readtime(struct device *dev, struct rtc_time *tm)
+{
+ struct wm8350 *wm8350 = dev_get_drvdata(dev);
+ u16 time1[4], time2[4];
+ int retries = WM8350_GET_TIME_RETRIES, ret;
+
+ /*
+ * Read the time twice and compare.
+ * If time1 == time2, then time is valid else retry.
+ */
+ do {
+ ret = wm8350_block_read(wm8350, WM8350_RTC_SECONDS_MINUTES,
+ 4, time1);
+ if (ret < 0)
+ return ret;
+ ret = wm8350_block_read(wm8350, WM8350_RTC_SECONDS_MINUTES,
+ 4, time2);
+ if (ret < 0)
+ return ret;
+
+ if (memcmp(time1, time2, sizeof(time1)) == 0) {
+ tm->tm_sec = time1[0] & WM8350_RTC_SECS_MASK;
+
+ tm->tm_min = (time1[0] & WM8350_RTC_MINS_MASK)
+ >> WM8350_RTC_MINS_SHIFT;
+
+ tm->tm_hour = time1[1] & WM8350_RTC_HRS_MASK;
+
+ tm->tm_wday = ((time1[1] >> WM8350_RTC_DAY_SHIFT)
+ & 0x7) - 1;
+
+ tm->tm_mon = ((time1[2] & WM8350_RTC_MTH_MASK)
+ >> WM8350_RTC_MTH_SHIFT) - 1;
+
+ tm->tm_mday = (time1[2] & WM8350_RTC_DATE_MASK);
+
+ tm->tm_year = ((time1[3] & WM8350_RTC_YHUNDREDS_MASK)
+ >> WM8350_RTC_YHUNDREDS_SHIFT) * 100;
+ tm->tm_year += time1[3] & WM8350_RTC_YUNITS_MASK;
+
+ tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon,
+ tm->tm_year);
+ tm->tm_year -= 1900;
+
+ dev_dbg(dev, "Read (%d left): %04x %04x %04x %04x\n",
+ retries,
+ time1[0], time1[1], time1[2], time1[3]);
+
+ return 0;
+ }
+ } while (retries--);
+
+ dev_err(dev, "timed out reading RTC time\n");
+ return -EIO;
+}
+
+/*
+ * Set current time and date in RTC
+ */
+static int wm8350_rtc_settime(struct device *dev, struct rtc_time *tm)
+{
+ struct wm8350 *wm8350 = dev_get_drvdata(dev);
+ u16 time[4];
+ u16 rtc_ctrl;
+ int ret, retries = WM8350_SET_TIME_RETRIES;
+
+ time[0] = tm->tm_sec;
+ time[0] |= tm->tm_min << WM8350_RTC_MINS_SHIFT;
+ time[1] = tm->tm_hour;
+ time[1] |= (tm->tm_wday + 1) << WM8350_RTC_DAY_SHIFT;
+ time[2] = tm->tm_mday;
+ time[2] |= (tm->tm_mon + 1) << WM8350_RTC_MTH_SHIFT;
+ time[3] = ((tm->tm_year + 1900) / 100) << WM8350_RTC_YHUNDREDS_SHIFT;
+ time[3] |= (tm->tm_year + 1900) % 100;
+
+ dev_dbg(dev, "Setting: %04x %04x %04x %04x\n",
+ time[0], time[1], time[2], time[3]);
+
+ /* Set RTC_SET to stop the clock */
+ ret = wm8350_set_bits(wm8350, WM8350_RTC_TIME_CONTROL, WM8350_RTC_SET);
+ if (ret < 0)
+ return ret;
+
+ /* Wait until confirmation of stopping */
+ do {
+ rtc_ctrl = wm8350_reg_read(wm8350, WM8350_RTC_TIME_CONTROL);
+ schedule_timeout_uninterruptible(msecs_to_jiffies(1));
+ } while (--retries && !(rtc_ctrl & WM8350_RTC_STS));
+
+ if (!retries) {
+ dev_err(dev, "timed out on set confirmation\n");
+ return -EIO;
+ }
+
+ /* Write time to RTC */
+ ret = wm8350_block_write(wm8350, WM8350_RTC_SECONDS_MINUTES, 4, time);
+ if (ret < 0)
+ return ret;
+
+ /* Clear RTC_SET to start the clock */
+ ret = wm8350_clear_bits(wm8350, WM8350_RTC_TIME_CONTROL,
+ WM8350_RTC_SET);
+ return ret;
+}
+
+/*
+ * Read alarm time and date in RTC
+ */
+static int wm8350_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct wm8350 *wm8350 = dev_get_drvdata(dev);
+ struct rtc_time *tm = &alrm->time;
+ u16 time[4];
+ int ret;
+
+ ret = wm8350_block_read(wm8350, WM8350_ALARM_SECONDS_MINUTES, 4, time);
+ if (ret < 0)
+ return ret;
+
+ tm->tm_sec = time[0] & WM8350_RTC_ALMSECS_MASK;
+ if (tm->tm_sec == WM8350_RTC_ALMSECS_MASK)
+ tm->tm_sec = -1;
+
+ tm->tm_min = time[0] & WM8350_RTC_ALMMINS_MASK;
+ if (tm->tm_min == WM8350_RTC_ALMMINS_MASK)
+ tm->tm_min = -1;
+ else
+ tm->tm_min >>= WM8350_RTC_ALMMINS_SHIFT;
+
+ tm->tm_hour = time[1] & WM8350_RTC_ALMHRS_MASK;
+ if (tm->tm_hour == WM8350_RTC_ALMHRS_MASK)
+ tm->tm_hour = -1;
+
+ tm->tm_wday = ((time[1] >> WM8350_RTC_ALMDAY_SHIFT) & 0x7) - 1;
+ if (tm->tm_wday > 7)
+ tm->tm_wday = -1;
+
+ tm->tm_mon = time[2] & WM8350_RTC_ALMMTH_MASK;
+ if (tm->tm_mon == WM8350_RTC_ALMMTH_MASK)
+ tm->tm_mon = -1;
+ else
+ tm->tm_mon = (tm->tm_mon >> WM8350_RTC_ALMMTH_SHIFT) - 1;
+
+ tm->tm_mday = (time[2] & WM8350_RTC_ALMDATE_MASK);
+ if (tm->tm_mday == WM8350_RTC_ALMDATE_MASK)
+ tm->tm_mday = -1;
+
+ tm->tm_year = -1;
+
+ alrm->enabled = !(time[3] & WM8350_RTC_ALMSTS);
+
+ return 0;
+}
+
+static int wm8350_rtc_stop_alarm(struct wm8350 *wm8350)
+{
+ int retries = WM8350_SET_ALM_RETRIES;
+ u16 rtc_ctrl;
+ int ret;
+
+ /* Set RTC_SET to stop the clock */
+ ret = wm8350_set_bits(wm8350, WM8350_RTC_TIME_CONTROL,
+ WM8350_RTC_ALMSET);
+ if (ret < 0)
+ return ret;
+
+ /* Wait until confirmation of stopping */
+ do {
+ rtc_ctrl = wm8350_reg_read(wm8350, WM8350_RTC_TIME_CONTROL);
+ schedule_timeout_uninterruptible(msecs_to_jiffies(1));
+ } while (retries-- && !(rtc_ctrl & WM8350_RTC_ALMSTS));
+
+ if (!(rtc_ctrl & WM8350_RTC_ALMSTS))
+ return -ETIMEDOUT;
+
+ return 0;
+}
+
+static int wm8350_rtc_start_alarm(struct wm8350 *wm8350)
+{
+ int ret;
+ int retries = WM8350_SET_ALM_RETRIES;
+ u16 rtc_ctrl;
+
+ ret = wm8350_clear_bits(wm8350, WM8350_RTC_TIME_CONTROL,
+ WM8350_RTC_ALMSET);
+ if (ret < 0)
+ return ret;
+
+ /* Wait until confirmation */
+ do {
+ rtc_ctrl = wm8350_reg_read(wm8350, WM8350_RTC_TIME_CONTROL);
+ schedule_timeout_uninterruptible(msecs_to_jiffies(1));
+ } while (retries-- && rtc_ctrl & WM8350_RTC_ALMSTS);
+
+ if (rtc_ctrl & WM8350_RTC_ALMSTS)
+ return -ETIMEDOUT;
+
+ return 0;
+}
+
+static int wm8350_rtc_alarm_irq_enable(struct device *dev,
+ unsigned int enabled)
+{
+ struct wm8350 *wm8350 = dev_get_drvdata(dev);
+
+ if (enabled)
+ return wm8350_rtc_start_alarm(wm8350);
+ else
+ return wm8350_rtc_stop_alarm(wm8350);
+}
+
+static int wm8350_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct wm8350 *wm8350 = dev_get_drvdata(dev);
+ struct rtc_time *tm = &alrm->time;
+ u16 time[3];
+ int ret;
+
+ memset(time, 0, sizeof(time));
+
+ if (tm->tm_sec != -1)
+ time[0] |= tm->tm_sec;
+ else
+ time[0] |= WM8350_RTC_ALMSECS_MASK;
+
+ if (tm->tm_min != -1)
+ time[0] |= tm->tm_min << WM8350_RTC_ALMMINS_SHIFT;
+ else
+ time[0] |= WM8350_RTC_ALMMINS_MASK;
+
+ if (tm->tm_hour != -1)
+ time[1] |= tm->tm_hour;
+ else
+ time[1] |= WM8350_RTC_ALMHRS_MASK;
+
+ if (tm->tm_wday != -1)
+ time[1] |= (tm->tm_wday + 1) << WM8350_RTC_ALMDAY_SHIFT;
+ else
+ time[1] |= WM8350_RTC_ALMDAY_MASK;
+
+ if (tm->tm_mday != -1)
+ time[2] |= tm->tm_mday;
+ else
+ time[2] |= WM8350_RTC_ALMDATE_MASK;
+
+ if (tm->tm_mon != -1)
+ time[2] |= (tm->tm_mon + 1) << WM8350_RTC_ALMMTH_SHIFT;
+ else
+ time[2] |= WM8350_RTC_ALMMTH_MASK;
+
+ ret = wm8350_rtc_stop_alarm(wm8350);
+ if (ret < 0)
+ return ret;
+
+ /* Write time to RTC */
+ ret = wm8350_block_write(wm8350, WM8350_ALARM_SECONDS_MINUTES,
+ 3, time);
+ if (ret < 0)
+ return ret;
+
+ if (alrm->enabled)
+ ret = wm8350_rtc_start_alarm(wm8350);
+
+ return ret;
+}
+
+static irqreturn_t wm8350_rtc_alarm_handler(int irq, void *data)
+{
+ struct wm8350 *wm8350 = data;
+ struct rtc_device *rtc = wm8350->rtc.rtc;
+ int ret;
+
+ rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF);
+
+ /* Make it one shot */
+ ret = wm8350_set_bits(wm8350, WM8350_RTC_TIME_CONTROL,
+ WM8350_RTC_ALMSET);
+ if (ret != 0) {
+ dev_err(&(wm8350->rtc.pdev->dev),
+ "Failed to disable alarm: %d\n", ret);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t wm8350_rtc_update_handler(int irq, void *data)
+{
+ struct wm8350 *wm8350 = data;
+ struct rtc_device *rtc = wm8350->rtc.rtc;
+
+ rtc_update_irq(rtc, 1, RTC_IRQF | RTC_UF);
+
+ return IRQ_HANDLED;
+}
+
+static const struct rtc_class_ops wm8350_rtc_ops = {
+ .read_time = wm8350_rtc_readtime,
+ .set_time = wm8350_rtc_settime,
+ .read_alarm = wm8350_rtc_readalarm,
+ .set_alarm = wm8350_rtc_setalarm,
+ .alarm_irq_enable = wm8350_rtc_alarm_irq_enable,
+};
+
+#ifdef CONFIG_PM_SLEEP
+static int wm8350_rtc_suspend(struct device *dev)
+{
+ struct wm8350 *wm8350 = dev_get_drvdata(dev);
+ int ret = 0;
+ u16 reg;
+
+ reg = wm8350_reg_read(wm8350, WM8350_RTC_TIME_CONTROL);
+
+ if (device_may_wakeup(&wm8350->rtc.pdev->dev) &&
+ reg & WM8350_RTC_ALMSTS) {
+ ret = wm8350_rtc_stop_alarm(wm8350);
+ if (ret != 0)
+ dev_err(dev, "Failed to stop RTC alarm: %d\n", ret);
+ }
+
+ return ret;
+}
+
+static int wm8350_rtc_resume(struct device *dev)
+{
+ struct wm8350 *wm8350 = dev_get_drvdata(dev);
+ int ret;
+
+ if (wm8350->rtc.alarm_enabled) {
+ ret = wm8350_rtc_start_alarm(wm8350);
+ if (ret != 0)
+ dev_err(dev, "Failed to restart RTC alarm: %d\n", ret);
+ }
+
+ return 0;
+}
+#endif
+
+static int wm8350_rtc_probe(struct platform_device *pdev)
+{
+ struct wm8350 *wm8350 = platform_get_drvdata(pdev);
+ struct wm8350_rtc *wm_rtc = &wm8350->rtc;
+ int ret = 0;
+ u16 timectl, power5;
+
+ timectl = wm8350_reg_read(wm8350, WM8350_RTC_TIME_CONTROL);
+ if (timectl & WM8350_RTC_BCD) {
+ dev_err(&pdev->dev, "RTC BCD mode not supported\n");
+ return -EINVAL;
+ }
+ if (timectl & WM8350_RTC_12HR) {
+ dev_err(&pdev->dev, "RTC 12 hour mode not supported\n");
+ return -EINVAL;
+ }
+
+ /* enable the RTC if it's not already enabled */
+ power5 = wm8350_reg_read(wm8350, WM8350_POWER_MGMT_5);
+ if (!(power5 & WM8350_RTC_TICK_ENA)) {
+ wm8350_reg_unlock(wm8350);
+
+ ret = wm8350_set_bits(wm8350, WM8350_POWER_MGMT_5,
+ WM8350_RTC_TICK_ENA);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to enable RTC: %d\n", ret);
+ return ret;
+ }
+
+ wm8350_reg_lock(wm8350);
+ }
+
+ if (timectl & WM8350_RTC_STS) {
+ int retries;
+
+ ret = wm8350_clear_bits(wm8350, WM8350_RTC_TIME_CONTROL,
+ WM8350_RTC_SET);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to start: %d\n", ret);
+ return ret;
+ }
+
+ retries = WM8350_SET_TIME_RETRIES;
+ do {
+ timectl = wm8350_reg_read(wm8350,
+ WM8350_RTC_TIME_CONTROL);
+ } while (timectl & WM8350_RTC_STS && --retries);
+
+ if (retries == 0) {
+ dev_err(&pdev->dev, "failed to start: timeout\n");
+ return -ENODEV;
+ }
+ }
+
+ device_init_wakeup(&pdev->dev, true);
+
+ wm_rtc->rtc = devm_rtc_device_register(&pdev->dev, "wm8350",
+ &wm8350_rtc_ops, THIS_MODULE);
+ if (IS_ERR(wm_rtc->rtc))
+ return PTR_ERR(wm_rtc->rtc);
+
+ ret = wm8350_register_irq(wm8350, WM8350_IRQ_RTC_SEC,
+ wm8350_rtc_update_handler, 0,
+ "RTC Seconds", wm8350);
+ if (ret)
+ return ret;
+
+ wm8350_mask_irq(wm8350, WM8350_IRQ_RTC_SEC);
+
+ ret = wm8350_register_irq(wm8350, WM8350_IRQ_RTC_ALM,
+ wm8350_rtc_alarm_handler, 0,
+ "RTC Alarm", wm8350);
+ if (ret) {
+ wm8350_free_irq(wm8350, WM8350_IRQ_RTC_SEC, wm8350);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void wm8350_rtc_remove(struct platform_device *pdev)
+{
+ struct wm8350 *wm8350 = platform_get_drvdata(pdev);
+
+ wm8350_free_irq(wm8350, WM8350_IRQ_RTC_SEC, wm8350);
+ wm8350_free_irq(wm8350, WM8350_IRQ_RTC_ALM, wm8350);
+}
+
+static SIMPLE_DEV_PM_OPS(wm8350_rtc_pm_ops, wm8350_rtc_suspend,
+ wm8350_rtc_resume);
+
+static struct platform_driver wm8350_rtc_driver = {
+ .probe = wm8350_rtc_probe,
+ .remove = wm8350_rtc_remove,
+ .driver = {
+ .name = "wm8350-rtc",
+ .pm = &wm8350_rtc_pm_ops,
+ },
+};
+
+module_platform_driver(wm8350_rtc_driver);
+
+MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
+MODULE_DESCRIPTION("RTC driver for the WM8350");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:wm8350-rtc");