+++ /dev/null
-From 5dcbf6d1aa6e33987082e9c8ac64e74f7b6bad58 Mon Sep 17 00:00:00 2001
-From: P33M <P33M@github.com>
-Date: Wed, 21 Oct 2015 14:55:21 +0100
-Subject: [PATCH] rpi_display: add backlight driver and overlay
-
-Add a mailbox-driven backlight controller for the Raspberry Pi DSI
-touchscreen display. Requires updated GPU firmware to recognise the
-mailbox request.
-
-Signed-off-by: Gordon Hollingworth <gordon@raspberrypi.org>
-
-Add Raspberry Pi firmware driver to the dependencies of backlight driver
-
-Otherwise the backlight driver fails to build if the firmware
-loading driver is not in the kernel
-
-Signed-off-by: Alex Riesen <alexander.riesen@cetitec.com>
----
- drivers/video/backlight/Kconfig | 7 ++
- drivers/video/backlight/Makefile | 1 +
- drivers/video/backlight/rpi_backlight.c | 119 ++++++++++++++++++++++++
- 3 files changed, 127 insertions(+)
- create mode 100644 drivers/video/backlight/rpi_backlight.c
-
---- a/drivers/video/backlight/Kconfig
-+++ b/drivers/video/backlight/Kconfig
-@@ -272,6 +272,13 @@ config BACKLIGHT_PWM
- If you have a LCD backlight adjustable by PWM, say Y to enable
- this driver.
-
-+config BACKLIGHT_RPI
-+ tristate "Raspberry Pi display firmware driven backlight"
-+ depends on RASPBERRYPI_FIRMWARE
-+ help
-+ If you have the Raspberry Pi DSI touchscreen display, say Y to
-+ enable the mailbox-controlled backlight driver.
-+
- config BACKLIGHT_DA903X
- tristate "Backlight Driver for DA9030/DA9034 using WLED"
- depends on PMIC_DA903X
---- a/drivers/video/backlight/Makefile
-+++ b/drivers/video/backlight/Makefile
-@@ -52,6 +52,7 @@ obj-$(CONFIG_BACKLIGHT_PANDORA) += pand
- obj-$(CONFIG_BACKLIGHT_PCF50633) += pcf50633-backlight.o
- obj-$(CONFIG_BACKLIGHT_PM8941_WLED) += pm8941-wled.o
- obj-$(CONFIG_BACKLIGHT_PWM) += pwm_bl.o
-+obj-$(CONFIG_BACKLIGHT_RPI) += rpi_backlight.o
- obj-$(CONFIG_BACKLIGHT_SAHARA) += kb3886_bl.o
- obj-$(CONFIG_BACKLIGHT_SKY81452) += sky81452-backlight.o
- obj-$(CONFIG_BACKLIGHT_TOSA) += tosa_bl.o
---- /dev/null
-+++ b/drivers/video/backlight/rpi_backlight.c
-@@ -0,0 +1,119 @@
-+/*
-+ * rpi_bl.c - Backlight controller through VPU
-+ *
-+ * 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/backlight.h>
-+#include <linux/err.h>
-+#include <linux/fb.h>
-+#include <linux/gpio.h>
-+#include <linux/init.h>
-+#include <linux/kernel.h>
-+#include <linux/module.h>
-+#include <linux/of.h>
-+#include <linux/of_gpio.h>
-+#include <linux/platform_device.h>
-+#include <linux/slab.h>
-+#include <soc/bcm2835/raspberrypi-firmware.h>
-+
-+struct rpi_backlight {
-+ struct device *dev;
-+ struct device *fbdev;
-+ struct rpi_firmware *fw;
-+};
-+
-+static int rpi_backlight_update_status(struct backlight_device *bl)
-+{
-+ struct rpi_backlight *gbl = bl_get_data(bl);
-+ int brightness = bl->props.brightness;
-+ int ret;
-+
-+ if (bl->props.power != FB_BLANK_UNBLANK ||
-+ bl->props.fb_blank != FB_BLANK_UNBLANK ||
-+ bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
-+ brightness = 0;
-+
-+ ret = rpi_firmware_property(gbl->fw,
-+ RPI_FIRMWARE_FRAMEBUFFER_SET_BACKLIGHT,
-+ &brightness, sizeof(brightness));
-+ if (ret) {
-+ dev_err(gbl->dev, "Failed to set brightness\n");
-+ return ret;
-+ }
-+
-+ if (brightness < 0) {
-+ dev_err(gbl->dev, "Backlight change failed\n");
-+ return -EAGAIN;
-+ }
-+
-+ return 0;
-+}
-+
-+static const struct backlight_ops rpi_backlight_ops = {
-+ .options = BL_CORE_SUSPENDRESUME,
-+ .update_status = rpi_backlight_update_status,
-+};
-+
-+static int rpi_backlight_probe(struct platform_device *pdev)
-+{
-+ struct backlight_properties props;
-+ struct backlight_device *bl;
-+ struct rpi_backlight *gbl;
-+ struct device_node *fw_node;
-+
-+ gbl = devm_kzalloc(&pdev->dev, sizeof(*gbl), GFP_KERNEL);
-+ if (gbl == NULL)
-+ return -ENOMEM;
-+
-+ gbl->dev = &pdev->dev;
-+
-+ fw_node = of_parse_phandle(pdev->dev.of_node, "firmware", 0);
-+ if (!fw_node) {
-+ dev_err(&pdev->dev, "Missing firmware node\n");
-+ return -ENOENT;
-+ }
-+
-+ gbl->fw = rpi_firmware_get(fw_node);
-+ if (!gbl->fw)
-+ return -EPROBE_DEFER;
-+
-+ memset(&props, 0, sizeof(props));
-+ props.type = BACKLIGHT_RAW;
-+ props.max_brightness = 255;
-+ bl = devm_backlight_device_register(&pdev->dev, dev_name(&pdev->dev),
-+ &pdev->dev, gbl, &rpi_backlight_ops,
-+ &props);
-+ if (IS_ERR(bl)) {
-+ dev_err(&pdev->dev, "failed to register backlight\n");
-+ return PTR_ERR(bl);
-+ }
-+
-+ bl->props.brightness = 255;
-+ backlight_update_status(bl);
-+
-+ platform_set_drvdata(pdev, bl);
-+ return 0;
-+}
-+
-+static const struct of_device_id rpi_backlight_of_match[] = {
-+ { .compatible = "raspberrypi,rpi-backlight" },
-+ { /* sentinel */ }
-+};
-+MODULE_DEVICE_TABLE(of, rpi_backlight_of_match);
-+
-+static struct platform_driver rpi_backlight_driver = {
-+ .driver = {
-+ .name = "rpi-backlight",
-+ .of_match_table = of_match_ptr(rpi_backlight_of_match),
-+ },
-+ .probe = rpi_backlight_probe,
-+};
-+
-+module_platform_driver(rpi_backlight_driver);
-+
-+MODULE_AUTHOR("Gordon Hollingworth <gordon@raspberrypi.org>");
-+MODULE_DESCRIPTION("Raspberry Pi mailbox based Backlight Driver");
-+MODULE_LICENSE("GPL");
projects / openwrt / staging / dedeckeh.git / blobdiff