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Diffstat (limited to 'kernel/arch/arm/plat-samsung/dev-backlight.c')
-rw-r--r--kernel/arch/arm/plat-samsung/dev-backlight.c152
1 files changed, 152 insertions, 0 deletions
diff --git a/kernel/arch/arm/plat-samsung/dev-backlight.c b/kernel/arch/arm/plat-samsung/dev-backlight.c
new file mode 100644
index 000000000..2157c5b53
--- /dev/null
+++ b/kernel/arch/arm/plat-samsung/dev-backlight.c
@@ -0,0 +1,152 @@
+/* linux/arch/arm/plat-samsung/dev-backlight.c
+ *
+ * Copyright (c) 2011 Samsung Electronics Co., Ltd.
+ * http://www.samsung.com
+ *
+ * Common infrastructure for PWM Backlight for Samsung boards
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/gpio.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/pwm_backlight.h>
+
+#include <plat/devs.h>
+#include <plat/gpio-cfg.h>
+#include <plat/backlight.h>
+
+struct samsung_bl_drvdata {
+ struct platform_pwm_backlight_data plat_data;
+ struct samsung_bl_gpio_info *gpio_info;
+};
+
+static int samsung_bl_init(struct device *dev)
+{
+ int ret = 0;
+ struct platform_pwm_backlight_data *pdata = dev->platform_data;
+ struct samsung_bl_drvdata *drvdata = container_of(pdata,
+ struct samsung_bl_drvdata, plat_data);
+ struct samsung_bl_gpio_info *bl_gpio_info = drvdata->gpio_info;
+
+ ret = gpio_request(bl_gpio_info->no, "Backlight");
+ if (ret) {
+ printk(KERN_ERR "failed to request GPIO for LCD Backlight\n");
+ return ret;
+ }
+
+ /* Configure GPIO pin with specific GPIO function for PWM timer */
+ s3c_gpio_cfgpin(bl_gpio_info->no, bl_gpio_info->func);
+
+ return 0;
+}
+
+static void samsung_bl_exit(struct device *dev)
+{
+ struct platform_pwm_backlight_data *pdata = dev->platform_data;
+ struct samsung_bl_drvdata *drvdata = container_of(pdata,
+ struct samsung_bl_drvdata, plat_data);
+ struct samsung_bl_gpio_info *bl_gpio_info = drvdata->gpio_info;
+
+ s3c_gpio_cfgpin(bl_gpio_info->no, S3C_GPIO_OUTPUT);
+ gpio_free(bl_gpio_info->no);
+}
+
+/* Initialize few important fields of platform_pwm_backlight_data
+ * structure with default values. These fields can be overridden by
+ * board-specific values sent from machine file.
+ * For ease of operation, these fields are initialized with values
+ * used by most samsung boards.
+ * Users has the option of sending info about other parameters
+ * for their specific boards
+ */
+
+static struct samsung_bl_drvdata samsung_dfl_bl_data __initdata = {
+ .plat_data = {
+ .max_brightness = 255,
+ .dft_brightness = 255,
+ .pwm_period_ns = 78770,
+ .enable_gpio = -1,
+ .init = samsung_bl_init,
+ .exit = samsung_bl_exit,
+ },
+};
+
+static struct platform_device samsung_dfl_bl_device __initdata = {
+ .name = "pwm-backlight",
+};
+
+/* samsung_bl_set - Set board specific data (if any) provided by user for
+ * PWM Backlight control and register specific PWM and backlight device.
+ * @gpio_info: structure containing GPIO info for PWM timer
+ * @bl_data: structure containing Backlight control data
+ */
+void __init samsung_bl_set(struct samsung_bl_gpio_info *gpio_info,
+ struct platform_pwm_backlight_data *bl_data)
+{
+ int ret = 0;
+ struct platform_device *samsung_bl_device;
+ struct samsung_bl_drvdata *samsung_bl_drvdata;
+ struct platform_pwm_backlight_data *samsung_bl_data;
+
+ samsung_bl_device = kmemdup(&samsung_dfl_bl_device,
+ sizeof(struct platform_device), GFP_KERNEL);
+ if (!samsung_bl_device) {
+ printk(KERN_ERR "%s: no memory for platform dev\n", __func__);
+ return;
+ }
+
+ samsung_bl_drvdata = kmemdup(&samsung_dfl_bl_data,
+ sizeof(samsung_dfl_bl_data), GFP_KERNEL);
+ if (!samsung_bl_drvdata) {
+ printk(KERN_ERR "%s: no memory for platform dev\n", __func__);
+ goto err_data;
+ }
+ samsung_bl_device->dev.platform_data = &samsung_bl_drvdata->plat_data;
+ samsung_bl_drvdata->gpio_info = gpio_info;
+ samsung_bl_data = &samsung_bl_drvdata->plat_data;
+
+ /* Copy board specific data provided by user */
+ samsung_bl_data->pwm_id = bl_data->pwm_id;
+ samsung_bl_device->dev.parent = &samsung_device_pwm.dev;
+
+ if (bl_data->max_brightness)
+ samsung_bl_data->max_brightness = bl_data->max_brightness;
+ if (bl_data->dft_brightness)
+ samsung_bl_data->dft_brightness = bl_data->dft_brightness;
+ if (bl_data->lth_brightness)
+ samsung_bl_data->lth_brightness = bl_data->lth_brightness;
+ if (bl_data->pwm_period_ns)
+ samsung_bl_data->pwm_period_ns = bl_data->pwm_period_ns;
+ if (bl_data->enable_gpio >= 0)
+ samsung_bl_data->enable_gpio = bl_data->enable_gpio;
+ if (bl_data->init)
+ samsung_bl_data->init = bl_data->init;
+ if (bl_data->notify)
+ samsung_bl_data->notify = bl_data->notify;
+ if (bl_data->notify_after)
+ samsung_bl_data->notify_after = bl_data->notify_after;
+ if (bl_data->exit)
+ samsung_bl_data->exit = bl_data->exit;
+ if (bl_data->check_fb)
+ samsung_bl_data->check_fb = bl_data->check_fb;
+
+ /* Register the Backlight dev */
+ ret = platform_device_register(samsung_bl_device);
+ if (ret) {
+ printk(KERN_ERR "failed to register backlight device: %d\n", ret);
+ goto err_plat_reg2;
+ }
+
+ return;
+
+err_plat_reg2:
+ kfree(samsung_bl_data);
+err_data:
+ kfree(samsung_bl_device);
+ return;
+}