From 4da2b00d471f7fca0d770551afafa95e85ec9b89 Mon Sep 17 00:00:00 2001 From: Eric Anholt Date: Tue, 26 Apr 2016 13:46:13 -0700 Subject: [PATCH] drm/panel: Add support for the Raspberry Pi 7" Touchscreen. Signed-off-by: Eric Anholt --- drivers/gpu/drm/panel/Kconfig | 9 + drivers/gpu/drm/panel/Makefile | 1 + .../gpu/drm/panel/panel-raspberrypi-touchscreen.c | 347 +++++++++++++++++++++ 3 files changed, 357 insertions(+) create mode 100644 drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c --- a/drivers/gpu/drm/panel/Kconfig +++ b/drivers/gpu/drm/panel/Kconfig @@ -31,6 +31,15 @@ config DRM_PANEL_LG_LG4573 Say Y here if you want to enable support for LG4573 RGB panel. To compile this driver as a module, choose M here. +config DRM_PANEL_RASPBERRYPI_TOUCHSCREEN + tristate "Raspberry Pi 7-inch touchscreen panel" + depends on DRM_MIPI_DSI + depends on BACKLIGHT_CLASS_DEVICE + help + Say Y here if you want to enable support for the Raspberry + Pi 7" Touchscreen. To compile this driver as a module, + choose M here. + config DRM_PANEL_SAMSUNG_S6E8AA0 tristate "Samsung S6E8AA0 DSI video mode panel" depends on OF --- a/drivers/gpu/drm/panel/Makefile +++ b/drivers/gpu/drm/panel/Makefile @@ -1,5 +1,6 @@ obj-$(CONFIG_DRM_PANEL_SIMPLE) += panel-simple.o obj-$(CONFIG_DRM_PANEL_LG_LG4573) += panel-lg-lg4573.o +obj-$(CONFIG_DRM_PANEL_RASPBERRYPI_TOUCHSCREEN) += panel-raspberrypi-touchscreen.o obj-$(CONFIG_DRM_PANEL_SAMSUNG_LD9040) += panel-samsung-ld9040.o obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E8AA0) += panel-samsung-s6e8aa0.o obj-$(CONFIG_DRM_PANEL_SHARP_LQ101R1SX01) += panel-sharp-lq101r1sx01.o --- /dev/null +++ b/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c @@ -0,0 +1,347 @@ +/* + * Copyright © 2016 Broadcom Limited + * + * 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. + * + * Portions of this file (derived from panel-simple.c) are: + * + * Copyright (C) 2013, NVIDIA Corporation. All rights reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sub license, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial portions + * of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + * DEALINGS IN THE SOFTWARE. + */ + +/** + * DOC: Raspberry Pi 7" touchscreen panel driver. + * + * The 7" touchscreen consists of a DPI LCD panel, a Toshiba + * TC358762XBG DSI-DPI bridge, and an I2C-connected Atmel ATTINY88-MUR + * controlling power management, the LCD PWM, and the touchscreen. + * + * This driver presents this device as a MIPI DSI panel to the DRM + * driver, and should expose the touchscreen as a HID device. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include + +struct rpi_touchscreen { + struct drm_panel base; + struct mipi_dsi_device *dsi; + struct i2c_client *bridge_i2c; + struct backlight_device *backlight; + + bool prepared; + bool enabled; + + /* Version of the firmware on the bridge chip */ + int atmel_ver; +}; + +static const struct drm_display_mode rpi_touchscreen_modes[] = { + { + /* This is assuming that we'll be running the DSI PLL + * at 2Ghz / 3 (since we only get integer dividers), + * so a pixel clock of 2Ghz / 3 / 8. + */ + .clock = 83333, + .hdisplay = 800, + .hsync_start = 800 + 61, + .hsync_end = 800 + 61 + 2, + .htotal = 800 + 61 + 2 + 44, + .vdisplay = 480, + .vsync_start = 480 + 7, + .vsync_end = 480 + 7 + 2, + .vtotal = 480 + 7 + 2 + 21, + .vrefresh = 60, + }, +}; + +static struct rpi_touchscreen *panel_to_ts(struct drm_panel *panel) +{ + return container_of(panel, struct rpi_touchscreen, base); +} + +struct regdump { + const char *reg; + u32 offset; +}; + +#define REGDUMP(reg) { #reg, reg } + +static int rpi_touchscreen_disable(struct drm_panel *panel) +{ + struct rpi_touchscreen *ts = panel_to_ts(panel); + pr_err("disable\n"); + + if (!ts->enabled) + return 0; + + if (ts->backlight) { + ts->backlight->props.power = FB_BLANK_POWERDOWN; + backlight_update_status(ts->backlight); + } + + ts->enabled = false; + + return 0; +} + +static int rpi_touchscreen_unprepare(struct drm_panel *panel) +{ + struct rpi_touchscreen *ts = panel_to_ts(panel); + + if (!ts->prepared) + return 0; + + ts->prepared = false; + + return 0; +} + +static int rpi_touchscreen_prepare(struct drm_panel *panel) +{ + struct rpi_touchscreen *ts = panel_to_ts(panel); + + if (ts->prepared) + return 0; + + ts->prepared = true; + + return 0; +} + +/* + * Powers on the panel once the DSI link is up. + * + * The TC358762 is run in PLLOFF mode, where it usees the MIPI DSI + * byte clock instead of an external reference clock. This means that + * we need the DSI host to be on and transmitting before we start + * talking to it. + */ +static int rpi_touchscreen_enable(struct drm_panel *panel) +{ + struct rpi_touchscreen *ts = panel_to_ts(panel); + + if (ts->enabled) + return 0; + + if (ts->backlight) { + ts->backlight->props.power = FB_BLANK_UNBLANK; + backlight_update_status(ts->backlight); + } + + ts->enabled = true; + + return 0; +} + +static int rpi_touchscreen_get_modes(struct drm_panel *panel) +{ + struct drm_connector *connector = panel->connector; + struct drm_device *drm = panel->drm; + unsigned int i, num = 0; + + for (i = 0; i < ARRAY_SIZE(rpi_touchscreen_modes); i++) { + const struct drm_display_mode *m = &rpi_touchscreen_modes[i]; + struct drm_display_mode *mode; + + mode = drm_mode_duplicate(drm, m); + if (!mode) { + dev_err(drm->dev, "failed to add mode %ux%u@%u\n", + m->hdisplay, m->vdisplay, m->vrefresh); + continue; + } + + mode->type |= DRM_MODE_TYPE_DRIVER; + + if (i == 0) + mode->type |= DRM_MODE_TYPE_PREFERRED; + + drm_mode_set_name(mode); + + drm_mode_probed_add(connector, mode); + num++; + } + + connector->display_info.bpc = 8; + connector->display_info.width_mm = 217; /* XXX */ + connector->display_info.height_mm = 136; /* XXX */ + + return num; +} + +static int rpi_touchscreen_backlight_update(struct backlight_device *bl) +{ + int brightness = bl->props.brightness; + + if (bl->props.power != FB_BLANK_UNBLANK || + bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK)) + brightness = 0; + + return 0; +} + +static const struct backlight_ops rpi_touchscreen_backlight_ops = { + .update_status = rpi_touchscreen_backlight_update, +}; + +static const struct drm_panel_funcs rpi_touchscreen_funcs = { + .disable = rpi_touchscreen_disable, + .unprepare = rpi_touchscreen_unprepare, + .prepare = rpi_touchscreen_prepare, + .enable = rpi_touchscreen_enable, + .get_modes = rpi_touchscreen_get_modes, +}; + +static struct i2c_client *rpi_touchscreen_get_i2c(struct device *dev, + const char *name) +{ + struct device_node *node; + struct i2c_client *client; + + node = of_parse_phandle(dev->of_node, name, 0); + if (!node) + return ERR_PTR(-ENODEV); + + client = of_find_i2c_device_by_node(node); + + of_node_put(node); + + return client; +} + +static int rpi_touchscreen_dsi_probe(struct mipi_dsi_device *dsi) +{ + struct device *dev = &dsi->dev; + struct rpi_touchscreen *ts; + int ret; + + ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL); + if (!ts) + return -ENOMEM; + + dev_set_drvdata(dev, ts); + + ts->dsi = dsi; + dsi->mode_flags = (MIPI_DSI_MODE_VIDEO | + MIPI_DSI_MODE_VIDEO_SYNC_PULSE); + dsi->format = MIPI_DSI_FMT_RGB888; + dsi->lanes = 1; + + ts->bridge_i2c = + rpi_touchscreen_get_i2c(dev, "raspberrypi,touchscreen-bridge"); + if (!ts->bridge_i2c) { + ret = -EPROBE_DEFER; + return ret; + } + +#if 0 + ts->backlight = + devm_backlight_device_register(dev, + "raspberrypi-touchscreen-backlight", + dev, ts, + &rpi_touchscreen_backlight_ops, + NULL); + if (IS_ERR(ts->backlight)) { + DRM_ERROR("failed to register backlight\n"); + return PTR_ERR(ts->backlight); + } + ts->backlight->props.max_brightness = RPI_TOUCHSCREEN_MAX_BRIGHTNESS; + ts->backlight->props.brightness = RPI_TOUCHSCREEN_MAX_BRIGHTNESS; +#endif + + drm_panel_init(&ts->base); + ts->base.dev = dev; + ts->base.funcs = &rpi_touchscreen_funcs; + + ret = drm_panel_add(&ts->base); + if (ret < 0) + goto err_release_bridge; + + return mipi_dsi_attach(dsi); + +err_release_bridge: + put_device(&ts->bridge_i2c->dev); + return ret; +} + +static int rpi_touchscreen_dsi_remove(struct mipi_dsi_device *dsi) +{ + struct device *dev = &dsi->dev; + struct rpi_touchscreen *ts = dev_get_drvdata(dev); + int ret; + + ret = mipi_dsi_detach(dsi); + if (ret < 0) { + dev_err(&dsi->dev, "failed to detach from DSI host: %d\n", ret); + return ret; + } + + drm_panel_detach(&ts->base); + drm_panel_remove(&ts->base); + + put_device(&ts->bridge_i2c->dev); + + return 0; +} + +static void rpi_touchscreen_dsi_shutdown(struct mipi_dsi_device *dsi) +{ + /* XXX: poweroff */ +} + +static const struct of_device_id rpi_touchscreen_of_match[] = { + { .compatible = "raspberrypi,touchscreen" }, + { } /* sentinel */ +}; +MODULE_DEVICE_TABLE(of, rpi_touchscreen_of_match); + +static struct mipi_dsi_driver rpi_touchscreen_driver = { + .driver = { + .name = "raspberrypi-touchscreen", + .of_match_table = rpi_touchscreen_of_match, + }, + .probe = rpi_touchscreen_dsi_probe, + .remove = rpi_touchscreen_dsi_remove, + .shutdown = rpi_touchscreen_dsi_shutdown, +}; +module_mipi_dsi_driver(rpi_touchscreen_driver); + +MODULE_AUTHOR("Eric Anholt "); +MODULE_DESCRIPTION("Raspberry Pi 7-inch touchscreen driver"); +MODULE_LICENSE("GPL v2");