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path: root/drivers/rtc/rtc-ep93xx.c
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Diffstat (limited to 'drivers/rtc/rtc-ep93xx.c')
-rw-r--r--drivers/rtc/rtc-ep93xx.c185
1 files changed, 185 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-ep93xx.c b/drivers/rtc/rtc-ep93xx.c
new file mode 100644
index 000000000..694038208
--- /dev/null
+++ b/drivers/rtc/rtc-ep93xx.c
@@ -0,0 +1,185 @@
+/*
+ * A driver for the RTC embedded in the Cirrus Logic EP93XX processors
+ * Copyright (c) 2006 Tower Technologies
+ *
+ * Author: Alessandro Zummo <a.zummo@towertech.it>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#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 (1<<0)
+#define EP93XX_RTC_LOAD 0x00C
+#define EP93XX_RTC_CONTROL 0x010
+#define EP93XX_RTC_CONTROL_MIE (1<<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 device dev.platform_data is used to store our private data
+ * because struct rtc_device does not have a variable to hold it.
+ */
+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_platdata(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_platdata(dev);
+ unsigned long time;
+
+ time = readl(ep93xx_rtc->mmio_base + EP93XX_RTC_DATA);
+
+ rtc_time_to_tm(time, tm);
+ return 0;
+}
+
+static int ep93xx_rtc_set_mmss(struct device *dev, unsigned long secs)
+{
+ struct ep93xx_rtc *ep93xx_rtc = dev_get_platdata(dev);
+
+ 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_mmss = ep93xx_rtc_set_mmss,
+ .proc = ep93xx_rtc_proc,
+};
+
+static ssize_t ep93xx_rtc_show_comp_preload(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ unsigned short preload;
+
+ ep93xx_rtc_get_swcomp(dev, &preload, NULL);
+
+ return sprintf(buf, "%d\n", preload);
+}
+static DEVICE_ATTR(comp_preload, S_IRUGO, ep93xx_rtc_show_comp_preload, NULL);
+
+static ssize_t ep93xx_rtc_show_comp_delete(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ unsigned short delete;
+
+ ep93xx_rtc_get_swcomp(dev, NULL, &delete);
+
+ return sprintf(buf, "%d\n", delete);
+}
+static DEVICE_ATTR(comp_delete, S_IRUGO, ep93xx_rtc_show_comp_delete, NULL);
+
+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;
+ struct resource *res;
+ int err;
+
+ ep93xx_rtc = devm_kzalloc(&pdev->dev, sizeof(*ep93xx_rtc), GFP_KERNEL);
+ if (!ep93xx_rtc)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ ep93xx_rtc->mmio_base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(ep93xx_rtc->mmio_base))
+ return PTR_ERR(ep93xx_rtc->mmio_base);
+
+ pdev->dev.platform_data = ep93xx_rtc;
+ platform_set_drvdata(pdev, ep93xx_rtc);
+
+ ep93xx_rtc->rtc = devm_rtc_device_register(&pdev->dev,
+ pdev->name, &ep93xx_rtc_ops, THIS_MODULE);
+ if (IS_ERR(ep93xx_rtc->rtc)) {
+ err = PTR_ERR(ep93xx_rtc->rtc);
+ goto exit;
+ }
+
+ err = sysfs_create_group(&pdev->dev.kobj, &ep93xx_rtc_sysfs_files);
+ if (err)
+ goto exit;
+
+ return 0;
+
+exit:
+ pdev->dev.platform_data = NULL;
+ return err;
+}
+
+static int ep93xx_rtc_remove(struct platform_device *pdev)
+{
+ sysfs_remove_group(&pdev->dev.kobj, &ep93xx_rtc_sysfs_files);
+ pdev->dev.platform_data = NULL;
+
+ return 0;
+}
+
+static struct platform_driver ep93xx_rtc_driver = {
+ .driver = {
+ .name = "ep93xx-rtc",
+ },
+ .probe = ep93xx_rtc_probe,
+ .remove = ep93xx_rtc_remove,
+};
+
+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");