[PATCH/HP7XX] - Add combined LCD / BL driver for platform HPJornada 7xx handhelds

From: Kristoffer Ericson
Date: Tue Feb 05 2008 - 13:53:51 EST


Greetings,

Richard I've cleaned up the driver by checking with checkpatch.pl as Russell suggested. I would appreciate it if you could
look through the patch again and give comments since the patch looks somewhat different.

I can add patch for Kconfig/Makefile later on but suspect there will be some changes required before that.

Oh and to answer your question regarding MAX/MIN values of the backlight, 0 = max and 255 = min. So we simply turn it around
by returning 255 - value. Same thing when we need to set value.

Best wishes
Kristoffer Ericson

diff --git a/drivers/video/backlight/jornada720_bllcd.c b/drivers/video/backlight/jornada720_bllcd.c
new file mode 100644
index 0000000..4967b86
--- /dev/null
+++ b/drivers/video/backlight/jornada720_bllcd.c
@@ -0,0 +1,284 @@
+/*
+ * drivers/video/backlight/jornada720_bllcd.c
+ *
+ * Backlight and LCD Driver for HP Jornada 720
+ * Copyright (C) 2007 Kristoffer Ericson <Kristoffer.Ericson@xxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * or any later version as published by the Free Software Foundation.
+ *
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/backlight.h>
+#include <linux/lcd.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/fb.h>
+#include <linux/device.h>
+#include <asm/hardware.h>
+#include <asm/arch/jornada720.h>
+#include <video/s1d13xxxfb.h>
+
+MODULE_AUTHOR("Kristoffer Ericson <kristoffer.ericson@xxxxxxxxx>");
+MODULE_DESCRIPTION("HP Jornada 710/720/728 Backlight/LCD Driver");
+MODULE_LICENSE("GPL");
+
+#define JORNADA_LCD_MAX_CONTRAST 0xff
+#define JORNADA_LCD_DEFAULT_CONTRAST 0x80
+#define JORNADA_BL_MAX_BRIGHTNESS 0xff
+#define JORNADA_BL_DEFAULT_BRIGHTNESS 0x19
+
+struct jornada_bllcd_device {
+ struct backlight_device *jorn_backlight_device;
+ struct lcd_device *jorn_lcd_device;
+};
+
+/*
+ * BACKLIGHT HANDLING ROUTINES
+ */
+static int jornada_bl_get_brightness(struct backlight_device *dev)
+{
+ int ret;
+
+ /* check if backlight is on */
+ if (!(PPSR & PPC_LDD1))
+ return 255;
+
+ jornada_ssp_start();
+ if (jornada_ssp_inout(GETBRIGHTNESS) == -ETIMEDOUT) {
+ printk(KERN_ERR "jornada720_bl: GetBrightness failed\n");
+ ret = 256;
+ } else
+ ret = jornada_ssp_inout(TXDUMMY);
+
+ jornada_ssp_end();
+
+ /* 0 is max brightness */
+ return (255 - ret);
+}
+
+static int jornada_bl_update_status(struct backlight_device *dev)
+{
+ int ret = 0;
+
+ jornada_ssp_start();
+
+ if (dev->props.power != FB_BLANK_UNBLANK ||
+ dev->props.fb_blank != FB_BLANK_UNBLANK) {
+ ret = jornada_ssp_inout(BRIGHTNESSOFF);
+ if (ret == -ETIMEDOUT)
+ printk(KERN_ERR "jornada720_bl:
+ BrightnessOff timeout\n");
+ else {
+ /* backlight off */
+ PPSR &= ~PPC_LDD1;
+ PPDR |= PPC_LDD1;
+ }
+ } else {/* backlight on */
+ PPSR |= PPC_LDD1;
+
+ if ((jornada_ssp_inout(SETBRIGHTNESS)) == TXDUMMY) {
+ /* send brightness value (0 is max, 255 lowest) */
+ if (jornada_ssp_byte(255 - dev->props.brightness) != -ETIMEDOUT)
+ ret = (255 - dev->props.brightness);
+ } else
+ printk(KERN_ERR "jornada720_bl: SetBrightness timeout\n");
+ }
+
+ jornada_ssp_end();
+
+ return ret;
+}
+
+/* LCD HANDLING FUNCTIONS
+ ====================== */
+static int jornada_lcd_set_contrast(struct lcd_device *pdev, int contrast)
+{
+ int ret = 0;
+
+ jornada_ssp_start();
+
+ ret = jornada_ssp_inout(SETCONTRAST);
+
+ if (ret == -ETIMEDOUT)
+ printk(KERN_INFO "jornada_lcd: failure to set contrast\n");
+ else
+ ret = jornada_ssp_byte(contrast);
+
+ jornada_ssp_end();
+
+ return ret;
+}
+
+static int jornada_lcd_set_power(struct lcd_device *pdev, int power)
+{
+ if (power != FB_BLANK_UNBLANK) {
+ /* turn off LCD */
+ PPSR &= ~PPC_LDD2;
+ PPDR |= PPC_LDD2;
+ } else
+ /* turn on LCD */
+ PPSR |= PPC_LDD2;
+
+ return 0;
+}
+
+static int jornada_lcd_get_power(struct lcd_device *pdev)
+{
+ if (PPSR & PPC_LDD2)
+ return FB_BLANK_UNBLANK;
+ else
+ return FB_BLANK_POWERDOWN;
+}
+
+static int jornada_lcd_get_contrast(struct lcd_device *pdev)
+{
+ int ret;
+
+ /* Don't set contrast on off powerd LCD */
+ if (jornada_lcd_get_power(pdev) != FB_BLANK_UNBLANK)
+ return 0;
+
+ jornada_ssp_start();
+
+ ret = jornada_ssp_inout(GETCONTRAST);
+ if (ret != -ETIMEDOUT)
+ ret = jornada_ssp_inout(TXDUMMY);
+ else {
+ printk(KERN_INFO "jornada_lcd: getcontrast failed!\n");
+ ret = 256;
+ }
+
+ jornada_ssp_end();
+
+ return ret;
+}
+
+static struct backlight_ops jornada_bl_ops = {
+ .get_brightness = jornada_bl_get_brightness,
+ .update_status = jornada_bl_update_status,
+};
+
+static struct lcd_ops jornada_lcd_ops = {
+ .get_contrast = jornada_lcd_get_contrast,
+ .set_contrast = jornada_lcd_set_contrast,
+ .get_power = jornada_lcd_get_power,
+ .set_power = jornada_lcd_set_power,
+};
+
+static int jornada_bl_probe(struct platform_device *pdev)
+{
+ struct jornada_bllcd_device *bllcd;
+
+ bllcd = kzalloc(sizeof(*bllcd), GFP_KERNEL);
+ if (bllcd == NULL)
+ return -ENOMEM;
+
+ /* bl driver - name must match fb driver name */
+ bllcd->jorn_backlight_device = backlight_device_register(S1D_DEVICENAME,
+ &pdev->dev, NULL, &jornada_bl_ops);
+
+ if (IS_ERR(bllcd->jorn_backlight_device)) {
+ kfree(bllcd);
+ return PTR_ERR(bllcd->jorn_backlight_device);
+ }
+
+ /* lcd driver */
+ bllcd->jorn_lcd_device = lcd_device_register(S1D_DEVICENAME,
+ &pdev->dev, NULL, &jornada_lcd_ops);
+ if (IS_ERR(bllcd->jorn_lcd_device)) {
+ kfree(bllcd);
+ return PTR_ERR(bllcd->jorn_lcd_device);
+ }
+
+ jornada_lcd_set_contrast(bllcd->jorn_lcd_device,
+ JORNADA_LCD_DEFAULT_CONTRAST);
+ jornada_lcd_set_power(bllcd->jorn_lcd_device,
+ FB_BLANK_UNBLANK);
+
+ msleep(100);
+
+ bllcd->jorn_backlight_device->props.power
+ = FB_BLANK_UNBLANK;
+ bllcd->jorn_backlight_device->props.brightness
+ = JORNADA_BL_DEFAULT_BRIGHTNESS;
+ jornada_bl_update_status(bllcd->jorn_backlight_device);
+
+ platform_set_drvdata(pdev, bllcd);
+ printk(KERN_INFO "HP Jornada 7xx Backlight/LCD driver activated\n");
+
+ return 0;
+}
+
+static int jornada_bl_remove(struct platform_device *pdev)
+{
+ struct jornada_bllcd_device *bllcd = platform_get_drvdata(pdev);
+
+ bllcd->jorn_backlight_device->props.power = FB_BLANK_POWERDOWN;
+ bllcd->jorn_backlight_device->props.brightness = 0;
+ bllcd->jorn_backlight_device->props.max_brightness = 0;
+
+ backlight_device_unregister(bllcd->jorn_backlight_device);
+ lcd_device_unregister(bllcd->jorn_lcd_device);
+
+ return 0;
+}
+
+static int jornada_bl_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ struct jornada_bllcd_device *bllcd = platform_get_drvdata(pdev);
+
+ bllcd->jorn_backlight_device->props.power = FB_BLANK_POWERDOWN;
+ bllcd->jorn_backlight_device->props.brightness = 0;
+ bllcd->jorn_backlight_device->props.max_brightness = 0;
+ jornada_bl_update_status(bllcd->jorn_backlight_device);
+
+ jornada_lcd_set_power(bllcd->jorn_lcd_device, FB_BLANK_POWERDOWN);
+
+ return 0;
+}
+
+static int jornada_bl_resume(struct platform_device *pdev)
+{
+ struct jornada_bllcd_device *bllcd = platform_get_drvdata(pdev);
+
+ bllcd->jorn_backlight_device->props.power
+ = FB_BLANK_UNBLANK;
+ bllcd->jorn_backlight_device->props.brightness
+ = JORNADA_BL_DEFAULT_BRIGHTNESS;
+ bllcd->jorn_backlight_device->props.max_brightness
+ = JORNADA_BL_MAX_BRIGHTNESS;
+ jornada_bl_update_status(bllcd->jorn_backlight_device);
+
+ jornada_lcd_set_power(bllcd->jorn_lcd_device, FB_BLANK_UNBLANK);
+
+ return 0;
+}
+
+static struct platform_driver jornada_bl_driver = {
+ .probe = jornada_bl_probe,
+ .remove = jornada_bl_remove,
+#ifdef CONFIG_PM
+ .suspend = jornada_bl_suspend,
+ .resume = jornada_bl_resume,
+#endif
+ .driver = {
+ .name = "jornada_bl",
+ },
+};
+
+static int __init jornada_bl_init(void)
+{
+ return platform_driver_register(&jornada_bl_driver);
+}
+
+static void __exit jornada_bl_exit(void)
+{
+ platform_driver_unregister(&jornada_bl_driver);
+}
+
+module_init(jornada_bl_init);
+module_exit(jornada_bl_exit);

Attachment: jornada720_bllcd.patch
Description: Binary data