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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/rtc/rtc-ep93xx.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--drivers/rtc/rtc-ep93xx.c163
1 files changed, 163 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-ep93xx.c b/drivers/rtc/rtc-ep93xx.c
new file mode 100644
index 000000000..acae7f168
--- /dev/null
+++ b/drivers/rtc/rtc-ep93xx.c
@@ -0,0 +1,163 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * A driver for the RTC embedded in the Cirrus Logic EP93XX processors
+ * Copyright (c) 2006 Tower Technologies
+ *
+ * Author: Alessandro Zummo <a.zummo@towertech.it>
+ */
+
+#include <linux/module.h>
+#include <linux/rtc.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/gfp.h>
+
+#define EP93XX_RTC_DATA 0x000
+#define EP93XX_RTC_MATCH 0x004
+#define EP93XX_RTC_STATUS 0x008
+#define EP93XX_RTC_STATUS_INTR BIT(0)
+#define EP93XX_RTC_LOAD 0x00C
+#define EP93XX_RTC_CONTROL 0x010
+#define EP93XX_RTC_CONTROL_MIE BIT(0)
+#define EP93XX_RTC_SWCOMP 0x108
+#define EP93XX_RTC_SWCOMP_DEL_MASK 0x001f0000
+#define EP93XX_RTC_SWCOMP_DEL_SHIFT 16
+#define EP93XX_RTC_SWCOMP_INT_MASK 0x0000ffff
+#define EP93XX_RTC_SWCOMP_INT_SHIFT 0
+
+struct ep93xx_rtc {
+ void __iomem *mmio_base;
+ struct rtc_device *rtc;
+};
+
+static int ep93xx_rtc_get_swcomp(struct device *dev, unsigned short *preload,
+ unsigned short *delete)
+{
+ struct ep93xx_rtc *ep93xx_rtc = dev_get_drvdata(dev);
+ unsigned long comp;
+
+ comp = readl(ep93xx_rtc->mmio_base + EP93XX_RTC_SWCOMP);
+
+ if (preload)
+ *preload = (comp & EP93XX_RTC_SWCOMP_INT_MASK)
+ >> EP93XX_RTC_SWCOMP_INT_SHIFT;
+
+ if (delete)
+ *delete = (comp & EP93XX_RTC_SWCOMP_DEL_MASK)
+ >> EP93XX_RTC_SWCOMP_DEL_SHIFT;
+
+ return 0;
+}
+
+static int ep93xx_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct ep93xx_rtc *ep93xx_rtc = dev_get_drvdata(dev);
+ unsigned long time;
+
+ time = readl(ep93xx_rtc->mmio_base + EP93XX_RTC_DATA);
+
+ rtc_time64_to_tm(time, tm);
+ return 0;
+}
+
+static int ep93xx_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct ep93xx_rtc *ep93xx_rtc = dev_get_drvdata(dev);
+ unsigned long secs = rtc_tm_to_time64(tm);
+
+ writel(secs + 1, ep93xx_rtc->mmio_base + EP93XX_RTC_LOAD);
+ return 0;
+}
+
+static int ep93xx_rtc_proc(struct device *dev, struct seq_file *seq)
+{
+ unsigned short preload, delete;
+
+ ep93xx_rtc_get_swcomp(dev, &preload, &delete);
+
+ seq_printf(seq, "preload\t\t: %d\n", preload);
+ seq_printf(seq, "delete\t\t: %d\n", delete);
+
+ return 0;
+}
+
+static const struct rtc_class_ops ep93xx_rtc_ops = {
+ .read_time = ep93xx_rtc_read_time,
+ .set_time = ep93xx_rtc_set_time,
+ .proc = ep93xx_rtc_proc,
+};
+
+static ssize_t comp_preload_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ unsigned short preload;
+
+ ep93xx_rtc_get_swcomp(dev->parent, &preload, NULL);
+
+ return sprintf(buf, "%d\n", preload);
+}
+static DEVICE_ATTR_RO(comp_preload);
+
+static ssize_t comp_delete_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ unsigned short delete;
+
+ ep93xx_rtc_get_swcomp(dev->parent, NULL, &delete);
+
+ return sprintf(buf, "%d\n", delete);
+}
+static DEVICE_ATTR_RO(comp_delete);
+
+static struct attribute *ep93xx_rtc_attrs[] = {
+ &dev_attr_comp_preload.attr,
+ &dev_attr_comp_delete.attr,
+ NULL
+};
+
+static const struct attribute_group ep93xx_rtc_sysfs_files = {
+ .attrs = ep93xx_rtc_attrs,
+};
+
+static int ep93xx_rtc_probe(struct platform_device *pdev)
+{
+ struct ep93xx_rtc *ep93xx_rtc;
+ int err;
+
+ ep93xx_rtc = devm_kzalloc(&pdev->dev, sizeof(*ep93xx_rtc), GFP_KERNEL);
+ if (!ep93xx_rtc)
+ return -ENOMEM;
+
+ ep93xx_rtc->mmio_base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(ep93xx_rtc->mmio_base))
+ return PTR_ERR(ep93xx_rtc->mmio_base);
+
+ platform_set_drvdata(pdev, ep93xx_rtc);
+
+ ep93xx_rtc->rtc = devm_rtc_allocate_device(&pdev->dev);
+ if (IS_ERR(ep93xx_rtc->rtc))
+ return PTR_ERR(ep93xx_rtc->rtc);
+
+ ep93xx_rtc->rtc->ops = &ep93xx_rtc_ops;
+ ep93xx_rtc->rtc->range_max = U32_MAX;
+
+ err = rtc_add_group(ep93xx_rtc->rtc, &ep93xx_rtc_sysfs_files);
+ if (err)
+ return err;
+
+ return devm_rtc_register_device(ep93xx_rtc->rtc);
+}
+
+static struct platform_driver ep93xx_rtc_driver = {
+ .driver = {
+ .name = "ep93xx-rtc",
+ },
+ .probe = ep93xx_rtc_probe,
+};
+
+module_platform_driver(ep93xx_rtc_driver);
+
+MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
+MODULE_DESCRIPTION("EP93XX RTC driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:ep93xx-rtc");