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-rw-r--r--drivers/video/backlight/Kconfig7
-rw-r--r--drivers/video/backlight/Makefile1
-rw-r--r--drivers/video/backlight/pcf50633-backlight.c190
3 files changed, 198 insertions, 0 deletions
diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index cbd80978460e..e54a337227ea 100644
--- a/drivers/video/backlight/Kconfig
+++ b/drivers/video/backlight/Kconfig
@@ -300,6 +300,13 @@ config BACKLIGHT_88PM860X
help
Say Y to enable the backlight driver for Marvell 88PM8606.
+config BACKLIGHT_PCF50633
+ tristate "Backlight driver for NXP PCF50633 MFD"
+ depends on BACKLIGHT_CLASS_DEVICE && MFD_PCF50633
+ help
+ If you have a backlight driven by a NXP PCF50633 MFD, say Y here to
+ enable its driver.
+
endif # BACKLIGHT_CLASS_DEVICE
endif # BACKLIGHT_LCD_SUPPORT
diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
index f8978c0a2319..44c0f81ad85d 100644
--- a/drivers/video/backlight/Makefile
+++ b/drivers/video/backlight/Makefile
@@ -34,4 +34,5 @@ obj-$(CONFIG_BACKLIGHT_ADX) += adx_bl.o
obj-$(CONFIG_BACKLIGHT_ADP5520) += adp5520_bl.o
obj-$(CONFIG_BACKLIGHT_ADP8860) += adp8860_bl.o
obj-$(CONFIG_BACKLIGHT_88PM860X) += 88pm860x_bl.o
+obj-$(CONFIG_BACKLIGHT_PCF50633) += pcf50633-backlight.o
diff --git a/drivers/video/backlight/pcf50633-backlight.c b/drivers/video/backlight/pcf50633-backlight.c
new file mode 100644
index 000000000000..3c424f7efdcc
--- /dev/null
+++ b/drivers/video/backlight/pcf50633-backlight.c
@@ -0,0 +1,190 @@
+/*
+ * Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
+ * PCF50633 backlight device driver
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+
+#include <linux/backlight.h>
+#include <linux/fb.h>
+
+#include <linux/mfd/pcf50633/core.h>
+#include <linux/mfd/pcf50633/backlight.h>
+
+struct pcf50633_bl {
+ struct pcf50633 *pcf;
+ struct backlight_device *bl;
+
+ unsigned int brightness;
+ unsigned int brightness_limit;
+};
+
+/*
+ * pcf50633_bl_set_brightness_limit
+ *
+ * Update the brightness limit for the pc50633 backlight. The actual brightness
+ * will not go above the limit. This is useful to limit power drain for example
+ * on low battery.
+ *
+ * @dev: Pointer to a pcf50633 device
+ * @limit: The brightness limit. Valid values are 0-63
+ */
+int pcf50633_bl_set_brightness_limit(struct pcf50633 *pcf, unsigned int limit)
+{
+ struct pcf50633_bl *pcf_bl = platform_get_drvdata(pcf->bl_pdev);
+
+ if (!pcf_bl)
+ return -ENODEV;
+
+ pcf_bl->brightness_limit = limit & 0x3f;
+ backlight_update_status(pcf_bl->bl);
+
+ return 0;
+}
+
+static int pcf50633_bl_update_status(struct backlight_device *bl)
+{
+ struct pcf50633_bl *pcf_bl = bl_get_data(bl);
+ unsigned int new_brightness;
+
+
+ if (bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK) ||
+ bl->props.power != FB_BLANK_UNBLANK)
+ new_brightness = 0;
+ else if (bl->props.brightness < pcf_bl->brightness_limit)
+ new_brightness = bl->props.brightness;
+ else
+ new_brightness = pcf_bl->brightness_limit;
+
+
+ if (pcf_bl->brightness == new_brightness)
+ return 0;
+
+ if (new_brightness) {
+ pcf50633_reg_write(pcf_bl->pcf, PCF50633_REG_LEDOUT,
+ new_brightness);
+ if (!pcf_bl->brightness)
+ pcf50633_reg_write(pcf_bl->pcf, PCF50633_REG_LEDENA, 1);
+ } else {
+ pcf50633_reg_write(pcf_bl->pcf, PCF50633_REG_LEDENA, 0);
+ }
+
+ pcf_bl->brightness = new_brightness;
+
+ return 0;
+}
+
+static int pcf50633_bl_get_brightness(struct backlight_device *bl)
+{
+ struct pcf50633_bl *pcf_bl = bl_get_data(bl);
+ return pcf_bl->brightness;
+}
+
+static const struct backlight_ops pcf50633_bl_ops = {
+ .get_brightness = pcf50633_bl_get_brightness,
+ .update_status = pcf50633_bl_update_status,
+ .options = BL_CORE_SUSPENDRESUME,
+};
+
+static int __devinit pcf50633_bl_probe(struct platform_device *pdev)
+{
+ int ret;
+ struct pcf50633_bl *pcf_bl;
+ struct device *parent = pdev->dev.parent;
+ struct pcf50633_platform_data *pcf50633_data = parent->platform_data;
+ struct pcf50633_bl_platform_data *pdata = pcf50633_data->backlight_data;
+ struct backlight_properties bl_props;
+
+ pcf_bl = kzalloc(sizeof(*pcf_bl), GFP_KERNEL);
+ if (!pcf_bl)
+ return -ENOMEM;
+
+ bl_props.max_brightness = 0x3f;
+ bl_props.power = FB_BLANK_UNBLANK;
+
+ if (pdata) {
+ bl_props.brightness = pdata->default_brightness;
+ pcf_bl->brightness_limit = pdata->default_brightness_limit;
+ } else {
+ bl_props.brightness = 0x3f;
+ pcf_bl->brightness_limit = 0x3f;
+ }
+
+ pcf_bl->pcf = dev_to_pcf50633(pdev->dev.parent);
+
+ pcf_bl->bl = backlight_device_register(pdev->name, &pdev->dev, pcf_bl,
+ &pcf50633_bl_ops, &bl_props);
+
+ if (IS_ERR(pcf_bl->bl)) {
+ ret = PTR_ERR(pcf_bl->bl);
+ goto err_free;
+ }
+
+ platform_set_drvdata(pdev, pcf_bl);
+
+ pcf50633_reg_write(pcf_bl->pcf, PCF50633_REG_LEDDIM, pdata->ramp_time);
+
+ /* Should be different from bl_props.brightness, so we do not exit
+ * update_status early the first time it's called */
+ pcf_bl->brightness = pcf_bl->bl->props.brightness + 1;
+
+ backlight_update_status(pcf_bl->bl);
+
+ return 0;
+
+err_free:
+ kfree(pcf_bl);
+
+ return ret;
+}
+
+static int __devexit pcf50633_bl_remove(struct platform_device *pdev)
+{
+ struct pcf50633_bl *pcf_bl = platform_get_drvdata(pdev);
+
+ backlight_device_unregister(pcf_bl->bl);
+
+ platform_set_drvdata(pdev, NULL);
+
+ kfree(pcf_bl);
+
+ return 0;
+}
+
+static struct platform_driver pcf50633_bl_driver = {
+ .probe = pcf50633_bl_probe,
+ .remove = __devexit_p(pcf50633_bl_remove),
+ .driver = {
+ .name = "pcf50633-backlight",
+ },
+};
+
+static int __init pcf50633_bl_init(void)
+{
+ return platform_driver_register(&pcf50633_bl_driver);
+}
+module_init(pcf50633_bl_init);
+
+static void __exit pcf50633_bl_exit(void)
+{
+ platform_driver_unregister(&pcf50633_bl_driver);
+}
+module_exit(pcf50633_bl_exit);
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_DESCRIPTION("PCF50633 backlight driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:pcf50633-backlight");
generated by cgit v1.2.3 (git 2.0.4) at 2024-11-14 01:46:06 +0000