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authorSebastian Andrzej Siewior <bigeasy@linutronix.de>2012-01-20 14:33:59 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-01-23 08:38:47 -0800
commite9a4593cc5e36c6d47c87b439cb41c2568e7395f (patch)
tree980bb0d0bacda4342b190a7e8d64b88731dfd8cd /drivers/leds/leds-ot200.c
parent656a070629adfe23c12768e35ddf91feab469ff7 (diff)
downloadop-kernel-dev-e9a4593cc5e36c6d47c87b439cb41c2568e7395f.zip
op-kernel-dev-e9a4593cc5e36c6d47c87b439cb41c2568e7395f.tar.gz
leds: add led driver for Bachmann's ot200
Add support for leds on Bachmann's ot200 visualisation device. The device has three leds on the back panel (led_err, led_init and led_run) and can handle up to seven leds on the front panel. The driver was written by Linutronix on behalf of Bachmann electronic GmbH. It incorporates feedback from Lars-Peter Clausen [akpm@linux-foundation.org: add dependency on HAS_IOMEM] Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/leds/leds-ot200.c')
-rw-r--r--drivers/leds/leds-ot200.c171
1 files changed, 171 insertions, 0 deletions
diff --git a/drivers/leds/leds-ot200.c b/drivers/leds/leds-ot200.c
new file mode 100644
index 0000000..c464682
--- /dev/null
+++ b/drivers/leds/leds-ot200.c
@@ -0,0 +1,171 @@
+/*
+ * Bachmann ot200 leds driver.
+ *
+ * Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+ * Christian Gmeiner <christian.gmeiner@gmail.com>
+ *
+ * License: GPL as published by the FSF.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/leds.h>
+#include <linux/io.h>
+#include <linux/module.h>
+
+
+struct ot200_led {
+ struct led_classdev cdev;
+ const char *name;
+ unsigned long port;
+ u8 mask;
+};
+
+/*
+ * The device has three leds on the back panel (led_err, led_init and led_run)
+ * and can handle up to seven leds on the front panel.
+ */
+
+static struct ot200_led leds[] = {
+ {
+ .name = "led_run",
+ .port = 0x5a,
+ .mask = BIT(0),
+ },
+ {
+ .name = "led_init",
+ .port = 0x5a,
+ .mask = BIT(1),
+ },
+ {
+ .name = "led_err",
+ .port = 0x5a,
+ .mask = BIT(2),
+ },
+ {
+ .name = "led_1",
+ .port = 0x49,
+ .mask = BIT(7),
+ },
+ {
+ .name = "led_2",
+ .port = 0x49,
+ .mask = BIT(6),
+ },
+ {
+ .name = "led_3",
+ .port = 0x49,
+ .mask = BIT(5),
+ },
+ {
+ .name = "led_4",
+ .port = 0x49,
+ .mask = BIT(4),
+ },
+ {
+ .name = "led_5",
+ .port = 0x49,
+ .mask = BIT(3),
+ },
+ {
+ .name = "led_6",
+ .port = 0x49,
+ .mask = BIT(2),
+ },
+ {
+ .name = "led_7",
+ .port = 0x49,
+ .mask = BIT(1),
+ }
+};
+
+static DEFINE_SPINLOCK(value_lock);
+
+/*
+ * we need to store the current led states, as it is not
+ * possible to read the current led state via inb().
+ */
+static u8 leds_back;
+static u8 leds_front;
+
+static void ot200_led_brightness_set(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ struct ot200_led *led = container_of(led_cdev, struct ot200_led, cdev);
+ u8 *val;
+ unsigned long flags;
+
+ spin_lock_irqsave(&value_lock, flags);
+
+ if (led->port == 0x49)
+ val = &leds_front;
+ else if (led->port == 0x5a)
+ val = &leds_back;
+ else
+ BUG();
+
+ if (value == LED_OFF)
+ *val &= ~led->mask;
+ else
+ *val |= led->mask;
+
+ outb(*val, led->port);
+ spin_unlock_irqrestore(&value_lock, flags);
+}
+
+static int __devinit ot200_led_probe(struct platform_device *pdev)
+{
+ int i;
+ int ret;
+
+ for (i = 0; i < ARRAY_SIZE(leds); i++) {
+
+ leds[i].cdev.name = leds[i].name;
+ leds[i].cdev.brightness_set = ot200_led_brightness_set;
+
+ ret = led_classdev_register(&pdev->dev, &leds[i].cdev);
+ if (ret < 0)
+ goto err;
+ }
+
+ leds_front = 0; /* turn off all front leds */
+ leds_back = BIT(1); /* turn on init led */
+ outb(leds_front, 0x49);
+ outb(leds_back, 0x5a);
+
+ return 0;
+
+err:
+ for (i = i - 1; i >= 0; i--)
+ led_classdev_unregister(&leds[i].cdev);
+
+ return ret;
+}
+
+static int __devexit ot200_led_remove(struct platform_device *pdev)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(leds); i++)
+ led_classdev_unregister(&leds[i].cdev);
+
+ return 0;
+}
+
+static struct platform_driver ot200_led_driver = {
+ .probe = ot200_led_probe,
+ .remove = __devexit_p(ot200_led_remove),
+ .driver = {
+ .name = "leds-ot200",
+ .owner = THIS_MODULE,
+ },
+};
+
+module_platform_driver(ot200_led_driver);
+
+MODULE_AUTHOR("Sebastian A. Siewior <bigeasy@linutronix.de>");
+MODULE_DESCRIPTION("ot200 LED driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:leds-ot200");
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