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path: root/drivers/video/backlight/ipaq_micro_bl.c
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Diffstat (limited to 'drivers/video/backlight/ipaq_micro_bl.c')
-rw-r--r--drivers/video/backlight/ipaq_micro_bl.c81
1 files changed, 81 insertions, 0 deletions
diff --git a/drivers/video/backlight/ipaq_micro_bl.c b/drivers/video/backlight/ipaq_micro_bl.c
new file mode 100644
index 000000000..85b16cc82
--- /dev/null
+++ b/drivers/video/backlight/ipaq_micro_bl.c
@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * iPAQ microcontroller backlight support
+ * Author : Linus Walleij <linus.walleij@linaro.org>
+ */
+
+#include <linux/backlight.h>
+#include <linux/err.h>
+#include <linux/fb.h>
+#include <linux/init.h>
+#include <linux/mfd/ipaq-micro.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+static int micro_bl_update_status(struct backlight_device *bd)
+{
+ struct ipaq_micro *micro = dev_get_drvdata(&bd->dev);
+ int intensity = bd->props.brightness;
+ struct ipaq_micro_msg msg = {
+ .id = MSG_BACKLIGHT,
+ .tx_len = 3,
+ };
+
+ if (bd->props.power != FB_BLANK_UNBLANK)
+ intensity = 0;
+ if (bd->props.state & (BL_CORE_FBBLANK | BL_CORE_SUSPENDED))
+ intensity = 0;
+
+ /*
+ * Message format:
+ * Byte 0: backlight instance (usually 1)
+ * Byte 1: on/off
+ * Byte 2: intensity, 0-255
+ */
+ msg.tx_data[0] = 0x01;
+ msg.tx_data[1] = intensity > 0 ? 1 : 0;
+ msg.tx_data[2] = intensity;
+ return ipaq_micro_tx_msg_sync(micro, &msg);
+}
+
+static const struct backlight_ops micro_bl_ops = {
+ .options = BL_CORE_SUSPENDRESUME,
+ .update_status = micro_bl_update_status,
+};
+
+static const struct backlight_properties micro_bl_props = {
+ .type = BACKLIGHT_RAW,
+ .max_brightness = 255,
+ .power = FB_BLANK_UNBLANK,
+ .brightness = 64,
+};
+
+static int micro_backlight_probe(struct platform_device *pdev)
+{
+ struct backlight_device *bd;
+ struct ipaq_micro *micro = dev_get_drvdata(pdev->dev.parent);
+
+ bd = devm_backlight_device_register(&pdev->dev, "ipaq-micro-backlight",
+ &pdev->dev, micro, &micro_bl_ops,
+ &micro_bl_props);
+ if (IS_ERR(bd))
+ return PTR_ERR(bd);
+
+ platform_set_drvdata(pdev, bd);
+ backlight_update_status(bd);
+
+ return 0;
+}
+
+static struct platform_driver micro_backlight_device_driver = {
+ .driver = {
+ .name = "ipaq-micro-backlight",
+ },
+ .probe = micro_backlight_probe,
+};
+module_platform_driver(micro_backlight_device_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("driver for iPAQ Atmel micro backlight");
+MODULE_ALIAS("platform:ipaq-micro-backlight");