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authorNiklas Cassel <cassel@kernel.org>2026-09-16 15:00:32 +0200
committerNiklas Cassel <cassel@kernel.org>2026-09-16 16:18:00 +0200
commit8d836581f9b1f57ceaa2b47654754ef1260b410b (patch)
tree1dbd4d0dfb99c2e238356cbe947e5b0be3e3a571 /drivers/rtc/rtc-nct6694.c
downloadlinux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.tar.gz
linux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.zip
ata: libata-scsi: fix ata_dsm_trim_pages() kernel-docgrafted
make htmldocs fails with: Documentation/driver-api/libata:604: ./drivers/ata/libata-scsi.c:2301: ERROR: Unexpected indentation. [docutils] The Return: section of ata_dsm_trim_pages() ends its first sentence with a colon and continues with an indented bullet list. reStructuredText requires a blank line before an indented block, so docutils chokes on the list. Simply adding the missing blank line does not work either: Return: is a kernel-doc "special section", which is terminated by the first blank line, so the bullet list would end up in the Description section, detached from the sentence introducing it. Spell the two bounds out as prose instead, so that the Return: section stays self-contained. Documentation-only change. Fixes: e64e6b5dc867 ("ata: libata-scsi: scale DSM TRIM payload by MAX PAGES PER DSM COMMAND") Reported-by: Thomas Huth <thuth@redhat.com> Closes: https://lore.kernel.org/linux-ide/b0a0b8e8-cc4f-4c7b-8bc5-fee0712d405a@redhat.com/ Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Link: https://lore.kernel.org/r/20260916130031.29990-2-cassel@kernel.org Signed-off-by: Niklas Cassel <cassel@kernel.org>
Diffstat (limited to 'drivers/rtc/rtc-nct6694.c')
-rw-r--r--drivers/rtc/rtc-nct6694.c297
1 files changed, 297 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-nct6694.c b/drivers/rtc/rtc-nct6694.c
new file mode 100644
index 000000000..35401a0d9
--- /dev/null
+++ b/drivers/rtc/rtc-nct6694.c
@@ -0,0 +1,297 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Nuvoton NCT6694 RTC driver based on USB interface.
+ *
+ * Copyright (C) 2025 Nuvoton Technology Corp.
+ */
+
+#include <linux/bcd.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/mfd/nct6694.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+#include <linux/slab.h>
+
+/*
+ * USB command module type for NCT6694 RTC controller.
+ * This defines the module type used for communication with the NCT6694
+ * RTC controller over the USB interface.
+ */
+#define NCT6694_RTC_MOD 0x08
+
+/* Command 00h - RTC Time */
+#define NCT6694_RTC_TIME 0x0000
+#define NCT6694_RTC_TIME_SEL 0x00
+
+/* Command 01h - RTC Alarm */
+#define NCT6694_RTC_ALARM 0x01
+#define NCT6694_RTC_ALARM_SEL 0x00
+
+/* Command 02h - RTC Status */
+#define NCT6694_RTC_STATUS 0x02
+#define NCT6694_RTC_STATUS_SEL 0x00
+
+#define NCT6694_RTC_IRQ_INT_EN BIT(0) /* Transmit a USB INT-in when RTC alarm */
+#define NCT6694_RTC_IRQ_GPO_EN BIT(5) /* Trigger a GPO Low Pulse when RTC alarm */
+
+#define NCT6694_RTC_IRQ_EN (NCT6694_RTC_IRQ_INT_EN | NCT6694_RTC_IRQ_GPO_EN)
+#define NCT6694_RTC_IRQ_STS BIT(0) /* Write 1 clear IRQ status */
+
+struct __packed nct6694_rtc_time {
+ u8 sec;
+ u8 min;
+ u8 hour;
+ u8 week;
+ u8 day;
+ u8 month;
+ u8 year;
+};
+
+struct __packed nct6694_rtc_alarm {
+ u8 sec;
+ u8 min;
+ u8 hour;
+ u8 alarm_en;
+ u8 alarm_pend;
+};
+
+struct __packed nct6694_rtc_status {
+ u8 irq_en;
+ u8 irq_pend;
+};
+
+union __packed nct6694_rtc_msg {
+ struct nct6694_rtc_time time;
+ struct nct6694_rtc_alarm alarm;
+ struct nct6694_rtc_status sts;
+};
+
+struct nct6694_rtc_data {
+ struct nct6694 *nct6694;
+ struct rtc_device *rtc;
+ union nct6694_rtc_msg *msg;
+ int irq;
+};
+
+static int nct6694_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct nct6694_rtc_data *data = dev_get_drvdata(dev);
+ struct nct6694_rtc_time *time = &data->msg->time;
+ static const struct nct6694_cmd_header cmd_hd = {
+ .mod = NCT6694_RTC_MOD,
+ .cmd = NCT6694_RTC_TIME,
+ .sel = NCT6694_RTC_TIME_SEL,
+ .len = cpu_to_le16(sizeof(*time))
+ };
+ int ret;
+
+ ret = nct6694_read_msg(data->nct6694, &cmd_hd, time);
+ if (ret)
+ return ret;
+
+ tm->tm_sec = bcd2bin(time->sec); /* tm_sec expect 0 ~ 59 */
+ tm->tm_min = bcd2bin(time->min); /* tm_min expect 0 ~ 59 */
+ tm->tm_hour = bcd2bin(time->hour); /* tm_hour expect 0 ~ 23 */
+ tm->tm_wday = bcd2bin(time->week) - 1; /* tm_wday expect 0 ~ 6 */
+ tm->tm_mday = bcd2bin(time->day); /* tm_mday expect 1 ~ 31 */
+ tm->tm_mon = bcd2bin(time->month) - 1; /* tm_month expect 0 ~ 11 */
+ tm->tm_year = bcd2bin(time->year) + 100; /* tm_year expect since 1900 */
+
+ return ret;
+}
+
+static int nct6694_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct nct6694_rtc_data *data = dev_get_drvdata(dev);
+ struct nct6694_rtc_time *time = &data->msg->time;
+ static const struct nct6694_cmd_header cmd_hd = {
+ .mod = NCT6694_RTC_MOD,
+ .cmd = NCT6694_RTC_TIME,
+ .sel = NCT6694_RTC_TIME_SEL,
+ .len = cpu_to_le16(sizeof(*time))
+ };
+
+ time->sec = bin2bcd(tm->tm_sec);
+ time->min = bin2bcd(tm->tm_min);
+ time->hour = bin2bcd(tm->tm_hour);
+ time->week = bin2bcd(tm->tm_wday + 1);
+ time->day = bin2bcd(tm->tm_mday);
+ time->month = bin2bcd(tm->tm_mon + 1);
+ time->year = bin2bcd(tm->tm_year - 100);
+
+ return nct6694_write_msg(data->nct6694, &cmd_hd, time);
+}
+
+static int nct6694_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct nct6694_rtc_data *data = dev_get_drvdata(dev);
+ struct nct6694_rtc_alarm *alarm = &data->msg->alarm;
+ static const struct nct6694_cmd_header cmd_hd = {
+ .mod = NCT6694_RTC_MOD,
+ .cmd = NCT6694_RTC_ALARM,
+ .sel = NCT6694_RTC_ALARM_SEL,
+ .len = cpu_to_le16(sizeof(*alarm))
+ };
+ int ret;
+
+ ret = nct6694_read_msg(data->nct6694, &cmd_hd, alarm);
+ if (ret)
+ return ret;
+
+ alrm->time.tm_sec = bcd2bin(alarm->sec);
+ alrm->time.tm_min = bcd2bin(alarm->min);
+ alrm->time.tm_hour = bcd2bin(alarm->hour);
+ alrm->enabled = alarm->alarm_en;
+ alrm->pending = alarm->alarm_pend;
+
+ return ret;
+}
+
+static int nct6694_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct nct6694_rtc_data *data = dev_get_drvdata(dev);
+ struct nct6694_rtc_alarm *alarm = &data->msg->alarm;
+ static const struct nct6694_cmd_header cmd_hd = {
+ .mod = NCT6694_RTC_MOD,
+ .cmd = NCT6694_RTC_ALARM,
+ .sel = NCT6694_RTC_ALARM_SEL,
+ .len = cpu_to_le16(sizeof(*alarm))
+ };
+
+ alarm->sec = bin2bcd(alrm->time.tm_sec);
+ alarm->min = bin2bcd(alrm->time.tm_min);
+ alarm->hour = bin2bcd(alrm->time.tm_hour);
+ alarm->alarm_en = alrm->enabled ? NCT6694_RTC_IRQ_EN : 0;
+ alarm->alarm_pend = 0;
+
+ return nct6694_write_msg(data->nct6694, &cmd_hd, alarm);
+}
+
+static int nct6694_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+ struct nct6694_rtc_data *data = dev_get_drvdata(dev);
+ struct nct6694_rtc_status *sts = &data->msg->sts;
+ static const struct nct6694_cmd_header cmd_hd = {
+ .mod = NCT6694_RTC_MOD,
+ .cmd = NCT6694_RTC_STATUS,
+ .sel = NCT6694_RTC_STATUS_SEL,
+ .len = cpu_to_le16(sizeof(*sts))
+ };
+
+ if (enabled)
+ sts->irq_en |= NCT6694_RTC_IRQ_EN;
+ else
+ sts->irq_en &= ~NCT6694_RTC_IRQ_EN;
+
+ sts->irq_pend = 0;
+
+ return nct6694_write_msg(data->nct6694, &cmd_hd, sts);
+}
+
+static const struct rtc_class_ops nct6694_rtc_ops = {
+ .read_time = nct6694_rtc_read_time,
+ .set_time = nct6694_rtc_set_time,
+ .read_alarm = nct6694_rtc_read_alarm,
+ .set_alarm = nct6694_rtc_set_alarm,
+ .alarm_irq_enable = nct6694_rtc_alarm_irq_enable,
+};
+
+static irqreturn_t nct6694_irq(int irq, void *dev_id)
+{
+ struct nct6694_rtc_data *data = dev_id;
+ struct nct6694_rtc_status *sts = &data->msg->sts;
+ static const struct nct6694_cmd_header cmd_hd = {
+ .mod = NCT6694_RTC_MOD,
+ .cmd = NCT6694_RTC_STATUS,
+ .sel = NCT6694_RTC_STATUS_SEL,
+ .len = cpu_to_le16(sizeof(*sts))
+ };
+ int ret;
+
+ rtc_lock(data->rtc);
+
+ sts->irq_en = NCT6694_RTC_IRQ_EN;
+ sts->irq_pend = NCT6694_RTC_IRQ_STS;
+ ret = nct6694_write_msg(data->nct6694, &cmd_hd, sts);
+ if (ret) {
+ rtc_unlock(data->rtc);
+ return IRQ_NONE;
+ }
+
+ rtc_update_irq(data->rtc, 1, RTC_IRQF | RTC_AF);
+
+ rtc_unlock(data->rtc);
+
+ return IRQ_HANDLED;
+}
+
+static void nct6694_irq_dispose_mapping(void *d)
+{
+ struct nct6694_rtc_data *data = d;
+
+ irq_dispose_mapping(data->irq);
+}
+
+static int nct6694_rtc_probe(struct platform_device *pdev)
+{
+ struct nct6694_rtc_data *data;
+ struct nct6694 *nct6694 = dev_get_drvdata(pdev->dev.parent);
+ int ret;
+
+ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->msg = devm_kzalloc(&pdev->dev, sizeof(union nct6694_rtc_msg),
+ GFP_KERNEL);
+ if (!data->msg)
+ return -ENOMEM;
+
+ data->irq = irq_create_mapping(nct6694->domain, NCT6694_IRQ_RTC);
+ if (!data->irq)
+ return -EINVAL;
+
+ ret = devm_add_action_or_reset(&pdev->dev, nct6694_irq_dispose_mapping,
+ data);
+ if (ret)
+ return ret;
+
+ ret = devm_device_init_wakeup(&pdev->dev);
+ if (ret)
+ return dev_err_probe(&pdev->dev, ret, "Failed to init wakeup\n");
+
+ data->rtc = devm_rtc_allocate_device(&pdev->dev);
+ if (IS_ERR(data->rtc))
+ return PTR_ERR(data->rtc);
+
+ data->nct6694 = nct6694;
+ data->rtc->ops = &nct6694_rtc_ops;
+ data->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
+ data->rtc->range_max = RTC_TIMESTAMP_END_2099;
+
+ platform_set_drvdata(pdev, data);
+
+ ret = devm_request_threaded_irq(&pdev->dev, data->irq, NULL,
+ nct6694_irq, IRQF_ONESHOT,
+ "rtc-nct6694", data);
+ if (ret < 0)
+ return dev_err_probe(&pdev->dev, ret, "Failed to request irq\n");
+
+ return devm_rtc_register_device(data->rtc);
+}
+
+static struct platform_driver nct6694_rtc_driver = {
+ .driver = {
+ .name = "nct6694-rtc",
+ },
+ .probe = nct6694_rtc_probe,
+};
+
+module_platform_driver(nct6694_rtc_driver);
+
+MODULE_DESCRIPTION("USB-RTC driver for NCT6694");
+MODULE_AUTHOR("Ming Yu <tmyu0@nuvoton.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:nct6694-rtc");