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-rw-r--r--arch/sh/drivers/heartbeat.c132
1 files changed, 132 insertions, 0 deletions
diff --git a/arch/sh/drivers/heartbeat.c b/arch/sh/drivers/heartbeat.c
new file mode 100644
index 000000000000..bc59cb6cd78b
--- /dev/null
+++ b/arch/sh/drivers/heartbeat.c
@@ -0,0 +1,132 @@
+/*
+ * Generic heartbeat driver for regular LED banks
+ *
+ * Copyright (C) 2007 Paul Mundt
+ *
+ * Most SH reference boards include a number of individual LEDs that can
+ * be independently controlled (either via a pre-defined hardware
+ * function or via the LED class, if desired -- the hardware tends to
+ * encapsulate some of the same "triggers" that the LED class supports,
+ * so there's not too much value in it).
+ *
+ * Additionally, most of these boards also have a LED bank that we've
+ * traditionally used for strobing the load average. This use case is
+ * handled by this driver, rather than giving each LED bit position its
+ * own struct device.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/io.h>
+
+#define DRV_NAME "heartbeat"
+#define DRV_VERSION "0.1.0"
+
+struct heartbeat_data {
+ void __iomem *base;
+ unsigned char bit_pos[8];
+ struct timer_list timer;
+};
+
+static void heartbeat_timer(unsigned long data)
+{
+ struct heartbeat_data *hd = (struct heartbeat_data *)data;
+ static unsigned bit = 0, up = 1;
+
+ ctrl_outw(1 << hd->bit_pos[bit], (unsigned long)hd->base);
+ if (up)
+ if (bit == (ARRAY_SIZE(hd->bit_pos) - 1)) {
+ bit--;
+ up = 0;
+ } else
+ bit++;
+ else if (bit == 0)
+ up = 1;
+ else
+ bit--;
+
+ mod_timer(&hd->timer, jiffies + (110 - ((300 << FSHIFT) /
+ ((avenrun[0] / 5) + (3 << FSHIFT)))));
+}
+
+static int heartbeat_drv_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct heartbeat_data *hd;
+
+ if (unlikely(pdev->num_resources != 1)) {
+ dev_err(&pdev->dev, "invalid number of resources\n");
+ return -EINVAL;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (unlikely(res == NULL)) {
+ dev_err(&pdev->dev, "invalid resource\n");
+ return -EINVAL;
+ }
+
+ hd = kmalloc(sizeof(struct heartbeat_data), GFP_KERNEL);
+ if (unlikely(!hd))
+ return -ENOMEM;
+
+ if (pdev->dev.platform_data) {
+ memcpy(hd->bit_pos, pdev->dev.platform_data,
+ ARRAY_SIZE(hd->bit_pos));
+ } else {
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(hd->bit_pos); i++)
+ hd->bit_pos[i] = i;
+ }
+
+ hd->base = (void __iomem *)res->start;
+
+ setup_timer(&hd->timer, heartbeat_timer, (unsigned long)hd);
+ platform_set_drvdata(pdev, hd);
+
+ return mod_timer(&hd->timer, jiffies + 1);
+}
+
+static int heartbeat_drv_remove(struct platform_device *pdev)
+{
+ struct heartbeat_data *hd = platform_get_drvdata(pdev);
+
+ del_timer_sync(&hd->timer);
+
+ platform_set_drvdata(pdev, NULL);
+
+ kfree(hd);
+
+ return 0;
+}
+
+static struct platform_driver heartbeat_driver = {
+ .probe = heartbeat_drv_probe,
+ .remove = heartbeat_drv_remove,
+ .driver = {
+ .name = DRV_NAME,
+ },
+};
+
+static int __init heartbeat_init(void)
+{
+ printk(KERN_NOTICE DRV_NAME ": version %s loaded\n", DRV_VERSION);
+ return platform_driver_register(&heartbeat_driver);
+}
+
+static void __exit heartbeat_exit(void)
+{
+ platform_driver_unregister(&heartbeat_driver);
+}
+module_init(heartbeat_init);
+module_exit(heartbeat_exit);
+
+MODULE_VERSION(DRV_VERSION);
+MODULE_AUTHOR("Paul Mundt");
+MODULE_LICENSE("GPLv2");
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