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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/sh/drivers/heartbeat.c
Initial import
Diffstat (limited to 'arch/sh/drivers/heartbeat.c')
-rw-r--r--arch/sh/drivers/heartbeat.c180
1 files changed, 180 insertions, 0 deletions
diff --git a/arch/sh/drivers/heartbeat.c b/arch/sh/drivers/heartbeat.c
new file mode 100644
index 000000000..7efc9c354
--- /dev/null
+++ b/arch/sh/drivers/heartbeat.c
@@ -0,0 +1,180 @@
+/*
+ * Generic heartbeat driver for regular LED banks
+ *
+ * Copyright (C) 2007 - 2010 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>
+#include <linux/slab.h>
+#include <asm/heartbeat.h>
+
+#define DRV_NAME "heartbeat"
+#define DRV_VERSION "0.1.2"
+
+static unsigned char default_bit_pos[] = { 0, 1, 2, 3, 4, 5, 6, 7 };
+
+static inline void heartbeat_toggle_bit(struct heartbeat_data *hd,
+ unsigned bit, unsigned int inverted)
+{
+ unsigned int new;
+
+ new = (1 << hd->bit_pos[bit]);
+ if (inverted)
+ new = ~new;
+
+ new &= hd->mask;
+
+ switch (hd->regsize) {
+ case 32:
+ new |= ioread32(hd->base) & ~hd->mask;
+ iowrite32(new, hd->base);
+ break;
+ case 16:
+ new |= ioread16(hd->base) & ~hd->mask;
+ iowrite16(new, hd->base);
+ break;
+ default:
+ new |= ioread8(hd->base) & ~hd->mask;
+ iowrite8(new, hd->base);
+ break;
+ }
+}
+
+static void heartbeat_timer(unsigned long data)
+{
+ struct heartbeat_data *hd = (struct heartbeat_data *)data;
+ static unsigned bit = 0, up = 1;
+
+ heartbeat_toggle_bit(hd, bit, hd->flags & HEARTBEAT_INVERTED);
+
+ bit += up;
+ if ((bit == 0) || (bit == (hd->nr_bits)-1))
+ up = -up;
+
+ 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;
+ int i;
+
+ 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;
+ }
+
+ if (pdev->dev.platform_data) {
+ hd = pdev->dev.platform_data;
+ } else {
+ hd = kzalloc(sizeof(struct heartbeat_data), GFP_KERNEL);
+ if (unlikely(!hd))
+ return -ENOMEM;
+ }
+
+ hd->base = ioremap_nocache(res->start, resource_size(res));
+ if (unlikely(!hd->base)) {
+ dev_err(&pdev->dev, "ioremap failed\n");
+
+ if (!pdev->dev.platform_data)
+ kfree(hd);
+
+ return -ENXIO;
+ }
+
+ if (!hd->nr_bits) {
+ hd->bit_pos = default_bit_pos;
+ hd->nr_bits = ARRAY_SIZE(default_bit_pos);
+ }
+
+ hd->mask = 0;
+ for (i = 0; i < hd->nr_bits; i++)
+ hd->mask |= (1 << hd->bit_pos[i]);
+
+ if (!hd->regsize) {
+ switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
+ case IORESOURCE_MEM_32BIT:
+ hd->regsize = 32;
+ break;
+ case IORESOURCE_MEM_16BIT:
+ hd->regsize = 16;
+ break;
+ case IORESOURCE_MEM_8BIT:
+ default:
+ hd->regsize = 8;
+ break;
+ }
+ }
+
+ 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);
+ iounmap(hd->base);
+
+ platform_set_drvdata(pdev, NULL);
+
+ if (!pdev->dev.platform_data)
+ 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("GPL v2");