A video bridge typically converts video from one format to another, e.g. DisplayPort to LVDS. Add driver model support for these with a simple interface to control activation and backlight. The uclass supports GPIO control of power and reset lines.
Signed-off-by: Simon Glass sjg@chromium.org ---
drivers/video/Kconfig | 2 + drivers/video/Makefile | 2 + drivers/video/bridge/Kconfig | 8 +++ drivers/video/bridge/Makefile | 7 ++ drivers/video/bridge/video-bridge-uclass.c | 111 +++++++++++++++++++++++++++++ include/dm/uclass-id.h | 1 + include/video_bridge.h | 92 ++++++++++++++++++++++++ 7 files changed, 223 insertions(+) create mode 100644 drivers/video/bridge/Kconfig create mode 100644 drivers/video/bridge/Makefile create mode 100644 drivers/video/bridge/video-bridge-uclass.c create mode 100644 include/video_bridge.h
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig index 9ae23e8..3244cd7 100644 --- a/drivers/video/Kconfig +++ b/drivers/video/Kconfig @@ -240,3 +240,5 @@ config VIDEO_TEGRA124 HDMI. At present only eDP is supported by U-Boot. This option enables this support which can be used on devices which have an eDP display connected. + +source "drivers/video/bridge/Kconfig" diff --git a/drivers/video/Makefile b/drivers/video/Makefile index 2ead7f1..599fe83 100644 --- a/drivers/video/Makefile +++ b/drivers/video/Makefile @@ -54,3 +54,5 @@ obj-$(CONFIG_AM335X_LCD) += am335x-fb.o obj-$(CONFIG_VIDEO_PARADE) += parade.o
obj-${CONFIG_VIDEO_TEGRA124} += tegra124/ + +obj-y += bridge/ diff --git a/drivers/video/bridge/Kconfig b/drivers/video/bridge/Kconfig new file mode 100644 index 0000000..7ba6b17 --- /dev/null +++ b/drivers/video/bridge/Kconfig @@ -0,0 +1,8 @@ +config VIDEO_BRIDGE + bool "Support video bridges" + depends on DM + help + Some platforms use video bridges to convert from one output to + another. For example, where the SoC only supports eDP and the LCD + requires LVDS, an eDP->LVDS bridge chip can be used to provide the + necessary conversion. This option enables support for these devices. diff --git a/drivers/video/bridge/Makefile b/drivers/video/bridge/Makefile new file mode 100644 index 0000000..f4bf087 --- /dev/null +++ b/drivers/video/bridge/Makefile @@ -0,0 +1,7 @@ +# +# Copyright (C) 2015 Google, Inc +# Written by Simon Glass sjg@chromium.org +# +# SPDX-License-Identifier: GPL-2.0+ + +obj-$(CONFIG_VIDEO_BRIDGE) += video-bridge-uclass.o diff --git a/drivers/video/bridge/video-bridge-uclass.c b/drivers/video/bridge/video-bridge-uclass.c new file mode 100644 index 0000000..e1ea428 --- /dev/null +++ b/drivers/video/bridge/video-bridge-uclass.c @@ -0,0 +1,111 @@ +/* + * Copyright (C) 2015 Google, Inc + * Written by Simon Glass sjg@chromium.org + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <dm.h> +#include <errno.h> +#include <video_bridge.h> + +int video_bridge_set_backlight(struct udevice *dev, int percent) +{ + struct video_bridge_ops *ops = video_bridge_get_ops(dev); + + if (!ops->set_backlight) + return -ENOSYS; + + return ops->set_backlight(dev, percent); +} + +int video_bridge_attach(struct udevice *dev) +{ + struct video_bridge_ops *ops = video_bridge_get_ops(dev); + + if (!ops->attach) + return -ENOSYS; + + return ops->attach(dev); +} + +int video_bridge_check_attached(struct udevice *dev) +{ + struct video_bridge_priv *uc_priv = dev_get_uclass_priv(dev); + struct video_bridge_ops *ops = video_bridge_get_ops(dev); + int ret; + + if (!ops->check_attached) { + ret = dm_gpio_get_value(&uc_priv->hotplug); + + return ret > 0 ? 0 : ret == 0 ? -ENOTCONN : ret; + } + + return ops->check_attached(dev); +} + +static int video_bridge_pre_probe(struct udevice *dev) +{ + struct video_bridge_priv *uc_priv = dev_get_uclass_priv(dev); + int ret; + + debug("%s\n", __func__); + ret = gpio_request_by_name(dev, "sleep-gpios", 0, + &uc_priv->sleep, GPIOD_IS_OUT); + if (ret) { + debug("%s: Could not decode sleep-gpios (%d)\n", __func__, ret); + return ret; + } + ret = dm_gpio_set_pull(&uc_priv->sleep, GPIO_PULL_NONE); + if (ret) { + debug("%s: Could not set sleep pull value\n", __func__); + return ret; + } + ret = gpio_request_by_name(dev, "reset-gpios", 0, &uc_priv->reset, + GPIOD_IS_OUT); + if (ret) { + debug("%s: Could not decode reset-gpios (%d)\n", __func__, ret); + return ret; + } + ret = dm_gpio_set_pull(&uc_priv->reset, GPIO_PULL_NONE); + if (ret) { + debug("%s: Could not set reset pull value\n", __func__); + return ret; + } + ret = gpio_request_by_name(dev, "hotplug-gpios", 0, &uc_priv->hotplug, + GPIOD_IS_IN); + if (ret && ret != -ENOENT) { + debug("%s: Could not decode hotplug (%d)\n", __func__, ret); + return ret; + } + + return 0; +} + +int video_bridge_set_active(struct udevice *dev, bool active) +{ + struct video_bridge_priv *uc_priv = dev_get_uclass_priv(dev); + int ret; + + debug("%s: %d\n", __func__, active); + ret = dm_gpio_set_value(&uc_priv->sleep, !active); + if (ret) + return ret; + if (active) { + ret = dm_gpio_set_value(&uc_priv->reset, true); + if (ret) + return ret; + udelay(10); + ret = dm_gpio_set_value(&uc_priv->reset, false); + } + + return ret; +} + +UCLASS_DRIVER(video_bridge) = { + .id = UCLASS_VIDEO_BRIDGE, + .name = "video_bridge", + .per_device_auto_alloc_size = sizeof(struct video_bridge_priv), + .pre_probe = video_bridge_pre_probe, +}; diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h index e2c3480..c1a6594 100644 --- a/include/dm/uclass-id.h +++ b/include/dm/uclass-id.h @@ -58,6 +58,7 @@ enum uclass_id { UCLASS_USB, /* USB bus */ UCLASS_USB_DEV_GENERIC, /* USB generic device */ UCLASS_USB_HUB, /* USB hub */ + UCLASS_VIDEO_BRIDGE, /* Video bridge, e.g. DisplayPort to LVDS */
UCLASS_COUNT, UCLASS_INVALID = -1, diff --git a/include/video_bridge.h b/include/video_bridge.h new file mode 100644 index 0000000..c7b8681 --- /dev/null +++ b/include/video_bridge.h @@ -0,0 +1,92 @@ +/* + * Copyright (C) 2015 Google, Inc + * Written by Simon Glass sjg@chromium.org + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef __VIDEO_BRIDGE +#define __VIDEO_BRIDGE + +#include <asm/gpio.h> + +/** + * struct video_bridge_priv - uclass information for video bridges + * + * @sleep: GPIO to assert to power down the bridge + * @reset: GPIO to assert to reset the bridge + * @hotplug: Optional GPIO to check if bridge is connected + */ +struct video_bridge_priv { + struct gpio_desc sleep; + struct gpio_desc reset; + struct gpio_desc hotplug; +}; + +/** + * Operations for video bridges + */ +struct video_bridge_ops { + /** + * attach() - attach a video bridge + * + * @return 0 if OK, -ve on error + */ + int (*attach)(struct udevice *dev); + + /** + * check_attached() - check if a bridge is correctly attached + * + * This method is optional - if not provided then the hotplug GPIO + * will be checked instead. + * + * @dev: Device to check + * @return 0 if attached, -EENOTCONN if not, or other -ve error + */ + int (*check_attached)(struct udevice *dev); + + /** + * set_backlight() - Set the backlight brightness + * + * @dev: device to adjust + * @percent: brightness percentage (0=off, 100=full brightness) + * @return 0 if OK, -ve on error + */ + int (*set_backlight)(struct udevice *dev, int percent); +}; + +#define video_bridge_get_ops(dev) \ + ((struct video_bridge_ops *)(dev)->driver->ops) + +/** + * video_bridge_attach() - attach a video bridge + * + * @return 0 if OK, -ve on error + */ +int video_bridge_attach(struct udevice *dev); + +/** + * video_bridge_set_backlight() - Set the backlight brightness + * + * @percent: brightness percentage (0=off, 100=full brightness) + * @return 0 if OK, -ve on error + */ +int video_bridge_set_backlight(struct udevice *dev, int percent); + +/** + * video_bridge_set_active() - take the bridge in/out of reset/powerdown + * + * @dev: Device to adjust + * @active: true to power up and reset, false to power down + */ +int video_bridge_set_active(struct udevice *dev, bool active); + +/** + * check_attached() - check if a bridge is correctly attached + * + * @dev: Device to check + * @return 0 if attached, -EENOTCONN if not, or other -ve error + */ +int video_bridge_check_attached(struct udevice *dev); + +#endif