[PATCH 2/4] RFC: drm/lcdc: add support for LCD panels (v2)

Rob Clark
2013-01-09T04:11:23Z

Add an output panel driver for LCD panels. Tested with LCD3 cape on
beaglebone.

TODO: need some way to control the appropriate backlight device
TODO: probably want to make the DT bindings more generic for panel-info

v1: original
v2: s/of_find_node_by_name()/of_get_child_by_name()/ from Pantelis
Antoniou

Signed-off-by: Rob Clark <robdclark@gmail.com>
---
drivers/gpu/drm/lcdc/Kconfig | 2 +
drivers/gpu/drm/lcdc/Makefile | 1 +
drivers/gpu/drm/lcdc/lcdc_drv.c | 3 +
drivers/gpu/drm/lcdc/lcdc_panel.c | 458 ++++++++++++++++++++++++++++++++++++++
drivers/gpu/drm/lcdc/lcdc_panel.h | 26 +++
5 files changed, 490 insertions(+)
create mode 100644 drivers/gpu/drm/lcdc/lcdc_panel.c
create mode 100644 drivers/gpu/drm/lcdc/lcdc_panel.h

diff --git a/drivers/gpu/drm/lcdc/Kconfig b/drivers/gpu/drm/lcdc/Kconfig
index 58806d4..7806184 100644
--- a/drivers/gpu/drm/lcdc/Kconfig
+++ b/drivers/gpu/drm/lcdc/Kconfig
@@ -4,6 +4,8 @@ config DRM_LCDC
select DRM_KMS_HELPER
select DRM_KMS_CMA_HELPER
select DRM_GEM_CMA_HELPER
+ select DISPLAY_TIMING
+ select OF_DISPLAY_TIMINGS
help
Choose this option if you have an TI SoC with LCDC display
controller, for example AM33xx in beagle-bone, DA8xx, or
diff --git a/drivers/gpu/drm/lcdc/Makefile b/drivers/gpu/drm/lcdc/Makefile
index db32161..27d19ce 100644
--- a/drivers/gpu/drm/lcdc/Makefile
+++ b/drivers/gpu/drm/lcdc/Makefile
@@ -3,6 +3,7 @@ ccflags-y := -Iinclude/drm -Werror
lcdc-y := \
lcdc_crtc.o \
lcdc_tfp410.o \
+ lcdc_panel.o \
lcdc_drv.o

obj-$(CONFIG_DRM_LCDC) += lcdc.o
diff --git a/drivers/gpu/drm/lcdc/lcdc_drv.c b/drivers/gpu/drm/lcdc/lcdc_drv.c
index 5e6d218..ee892cb 100644
--- a/drivers/gpu/drm/lcdc/lcdc_drv.c
+++ b/drivers/gpu/drm/lcdc/lcdc_drv.c
@@ -20,6 +20,7 @@
#include "lcdc_drv.h"
#include "lcdc_regs.h"
#include "lcdc_tfp410.h"
+#include "lcdc_panel.h"

#include "drm_fb_helper.h"

@@ -584,6 +585,7 @@ static int __init lcdc_drm_init(void)
{
DBG("init");
lcdc_tfp410_init();
+ lcdc_panel_init();
return platform_driver_register(&lcdc_platform_driver);
}

@@ -591,6 +593,7 @@ static void __exit lcdc_drm_fini(void)
{
DBG("fini");
lcdc_tfp410_fini();
+ lcdc_panel_fini();
platform_driver_unregister(&lcdc_platform_driver);
}

diff --git a/drivers/gpu/drm/lcdc/lcdc_panel.c b/drivers/gpu/drm/lcdc/lcdc_panel.c
new file mode 100644
index 0000000..037e2d2
--- /dev/null
+++ b/drivers/gpu/drm/lcdc/lcdc_panel.c
@@ -0,0 +1,458 @@
+/*
+ * Copyright (C) 2012 Texas Instruments
+ * Author: Rob Clark <robdclark@gmail.com>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/pinctrl/pinmux.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/of_display_timings.h>
+
+#include "lcdc_drv.h"
+
+struct panel_module {
+ struct lcdc_module base;
+ struct lcdc_panel_info *info;
+ struct display_timings *timings;
+};
+#define to_panel_module(x) container_of(x, struct panel_module, base)
+
+
+/*
+ * Encoder:
+ */
+
+struct panel_encoder {
+ struct drm_encoder base;
+ struct panel_module *mod;
+};
+#define to_panel_encoder(x) container_of(x, struct panel_encoder, base)
+
+
+static void panel_encoder_destroy(struct drm_encoder *encoder)
+{
+ struct panel_encoder *panel_encoder = to_panel_encoder(encoder);
+ drm_encoder_cleanup(encoder);
+ kfree(panel_encoder);
+}
+
+static void panel_encoder_dpms(struct drm_encoder *encoder, int mode)
+{
+}
+
+static bool panel_encoder_mode_fixup(struct drm_encoder *encoder,
+ const struct drm_display_mode *mode,
+ struct drm_display_mode *adjusted_mode)
+{
+ /* nothing needed */
+ return true;
+}
+
+static void panel_encoder_prepare(struct drm_encoder *encoder)
+{
+ struct panel_encoder *panel_encoder = to_panel_encoder(encoder);
+ panel_encoder_dpms(encoder, DRM_MODE_DPMS_OFF);
+ lcdc_crtc_set_panel_info(encoder->crtc, panel_encoder->mod->info);
+}
+
+static void panel_encoder_commit(struct drm_encoder *encoder)
+{
+ panel_encoder_dpms(encoder, DRM_MODE_DPMS_ON);
+}
+
+static void panel_encoder_mode_set(struct drm_encoder *encoder,
+ struct drm_display_mode *mode,
+ struct drm_display_mode *adjusted_mode)
+{
+ /* nothing needed */
+}
+
+static const struct drm_encoder_funcs panel_encoder_funcs = {
+ .destroy = panel_encoder_destroy,
+};
+
+static const struct drm_encoder_helper_funcs panel_encoder_helper_funcs = {
+ .dpms = panel_encoder_dpms,
+ .mode_fixup = panel_encoder_mode_fixup,
+ .prepare = panel_encoder_prepare,
+ .commit = panel_encoder_commit,
+ .mode_set = panel_encoder_mode_set,
+};
+
+static struct drm_encoder *panel_encoder_create(struct drm_device *dev,
+ struct panel_module *mod)
+{
+ struct panel_encoder *panel_encoder;
+ struct drm_encoder *encoder;
+ int ret;
+
+ panel_encoder = kzalloc(sizeof(*panel_encoder), GFP_KERNEL);
+ if (!panel_encoder) {
+ dev_err(dev->dev, "allocation failed\n");
+ return NULL;
+ }
+
+ panel_encoder->mod = mod;
+
+ encoder = &panel_encoder->base;
+ encoder->possible_crtcs = 1;
+
+ ret = drm_encoder_init(dev, encoder, &panel_encoder_funcs,
+ DRM_MODE_ENCODER_LVDS);
+ if (ret < 0)
+ goto fail;
+
+ drm_encoder_helper_add(encoder, &panel_encoder_helper_funcs);
+
+ return encoder;
+
+fail:
+ panel_encoder_destroy(encoder);
+ return NULL;
+}
+
+/*
+ * Connector:
+ */
+
+struct panel_connector {
+ struct drm_connector base;
+
+ struct drm_encoder *encoder; /* our connected encoder */
+ struct panel_module *mod;
+};
+#define to_panel_connector(x) container_of(x, struct panel_connector, base)
+
+
+static void panel_connector_destroy(struct drm_connector *connector)
+{
+ struct panel_connector *panel_connector = to_panel_connector(connector);
+ drm_connector_cleanup(connector);
+ kfree(panel_connector);
+}
+
+static enum drm_connector_status panel_connector_detect(
+ struct drm_connector *connector,
+ bool force)
+{
+ return connector_status_connected;
+}
+
+/* maybe this should be helper in drm-core? */
+static inline void copy_timings_to_drm(struct drm_display_mode *mode,
+ struct display_timing *timing)
+{
+ mode->clock = timing->pixelclock.typ / 1000;
+
+ mode->hdisplay = timing->hactive.typ;
+ mode->hsync_start = mode->hdisplay + timing->hfront_porch.typ;
+ mode->hsync_end = mode->hsync_start + timing->hsync_len.typ;
+ mode->htotal = mode->hsync_end + timing->hback_porch.typ;
+
+ mode->vdisplay = timing->vactive.typ;
+ mode->vsync_start = mode->vdisplay + timing->vfront_porch.typ;
+ mode->vsync_end = mode->vsync_start + timing->vsync_len.typ;
+ mode->vtotal = mode->vsync_end + timing->vback_porch.typ;
+
+ mode->flags = 0;
+
+ if (timing->interlaced)
+ mode->flags |= DRM_MODE_FLAG_INTERLACE;
+
+ if (timing->doublescan)
+ mode->flags |= DRM_MODE_FLAG_DBLSCAN;
+
+ if (timing->hsync_pol_active)
+ mode->flags |= DRM_MODE_FLAG_PHSYNC;
+ else
+ mode->flags |= DRM_MODE_FLAG_NHSYNC;
+
+ if (timing->vsync_pol_active)
+ mode->flags |= DRM_MODE_FLAG_PVSYNC;
+ else
+ mode->flags |= DRM_MODE_FLAG_NVSYNC;
+}
+
+static int panel_connector_get_modes(struct drm_connector *connector)
+{
+ struct drm_device *dev = connector->dev;
+ struct panel_connector *panel_connector = to_panel_connector(connector);
+ struct display_timings *timings = panel_connector->mod->timings;
+ int i;
+
+ for (i = 0; i < timings->num_timings; i++) {
+ struct drm_display_mode *mode = drm_mode_create(dev);
+
+ copy_timings_to_drm(mode, display_timings_get(timings, i));
+
+ mode->type = DRM_MODE_TYPE_DRIVER;
+
+ if (timings->native_mode == i)
+ mode->type |= DRM_MODE_TYPE_PREFERRED;
+
+ drm_mode_set_name(mode);
+ drm_mode_probed_add(connector, mode);
+ }
+
+ return timings->num_timings;
+}
+
+static int panel_connector_mode_valid(struct drm_connector *connector,
+ struct drm_display_mode *mode)
+{
+ struct lcdc_drm_private *priv = connector->dev->dev_private;
+ /* our only constraints are what the crtc can generate: */
+ return lcdc_crtc_mode_valid(priv->crtc, mode);
+}
+
+static struct drm_encoder *panel_connector_best_encoder(
+ struct drm_connector *connector)
+{
+ struct panel_connector *panel_connector = to_panel_connector(connector);
+ return panel_connector->encoder;
+}
+
+static const struct drm_connector_funcs panel_connector_funcs = {
+ .destroy = panel_connector_destroy,
+ .dpms = drm_helper_connector_dpms,
+ .detect = panel_connector_detect,
+ .fill_modes = drm_helper_probe_single_connector_modes,
+};
+
+static const struct drm_connector_helper_funcs panel_connector_helper_funcs = {
+ .get_modes = panel_connector_get_modes,
+ .mode_valid = panel_connector_mode_valid,
+ .best_encoder = panel_connector_best_encoder,
+};
+
+static struct drm_connector *panel_connector_create(struct drm_device *dev,
+ struct panel_module *mod, struct drm_encoder *encoder)
+{
+ struct panel_connector *panel_connector;
+ struct drm_connector *connector;
+ int ret;
+
+ panel_connector = kzalloc(sizeof(*panel_connector), GFP_KERNEL);
+ if (!panel_connector) {
+ dev_err(dev->dev, "allocation failed\n");
+ return NULL;
+ }
+
+ panel_connector->encoder = encoder;
+ panel_connector->mod = mod;
+
+ connector = &panel_connector->base;
+
+ drm_connector_init(dev, connector, &panel_connector_funcs,
+ DRM_MODE_CONNECTOR_LVDS);
+ drm_connector_helper_add(connector, &panel_connector_helper_funcs);
+
+ connector->interlace_allowed = 0;
+ connector->doublescan_allowed = 0;
+
+ ret = drm_mode_connector_attach_encoder(connector, encoder);
+ if (ret)
+ goto fail;
+
+ drm_sysfs_connector_add(connector);
+
+ return connector;
+
+fail:
+ panel_connector_destroy(connector);
+ return NULL;
+}
+
+/*
+ * Module:
+ */
+
+static int panel_modeset_init(struct lcdc_module *mod, struct drm_device *dev)
+{
+ struct panel_module *panel_mod = to_panel_module(mod);
+ struct lcdc_drm_private *priv = dev->dev_private;
+ struct drm_encoder *encoder;
+ struct drm_connector *connector;
+
+ encoder = panel_encoder_create(dev, panel_mod);
+ if (!encoder)
+ return -ENOMEM;
+
+ connector = panel_connector_create(dev, panel_mod, encoder);
+ if (!connector)
+ return -ENOMEM;
+
+ priv->encoders[priv->num_encoders++] = encoder;
+ priv->connectors[priv->num_connectors++] = connector;
+
+ return 0;
+}
+
+static void panel_destroy(struct lcdc_module *mod)
+{
+ struct panel_module *panel_mod = to_panel_module(mod);
+
+ if (panel_mod->timings) {
+ display_timings_release(panel_mod->timings);
+ kfree(panel_mod->timings);
+ }
+
+ lcdc_module_cleanup(mod);
+ kfree(panel_mod->info);
+ kfree(panel_mod);
+}
+
+static const struct lcdc_module_ops panel_module_ops = {
+ .modeset_init = panel_modeset_init,
+ .destroy = panel_destroy,
+};
+
+/*
+ * Device:
+ */
+
+/* maybe move this somewhere common if it is needed by other outputs? */
+static struct lcdc_panel_info * of_get_panel_info(struct device_node *np)
+{
+ struct device_node *info_np;
+ struct lcdc_panel_info *info;
+ int ret = 0;
+
+ if (!np) {
+ pr_err("%s: no devicenode given\n", __func__);
+ return NULL;
+ }
+
+ info_np = of_get_child_by_name(np, "panel-info");
+ if (!info_np) {
+ pr_err("%s: could not find panel-info node\n", __func__);
+ return NULL;
+ }
+
+ info = kzalloc(sizeof(*info), GFP_KERNEL);
+ if (!info) {
+ pr_err("%s: allocation failed\n", __func__);
+ return NULL;
+ }
+
+ ret |= of_property_read_u32(info_np, "ac-bias", &info->ac_bias);
+ ret |= of_property_read_u32(info_np, "ac-bias-intrpt", &info->ac_bias_intrpt);
+ ret |= of_property_read_u32(info_np, "dma-burst-sz", &info->dma_burst_sz);
+ ret |= of_property_read_u32(info_np, "bpp", &info->bpp);
+ ret |= of_property_read_u32(info_np, "fdd", &info->fdd);
+ ret |= of_property_read_u32(info_np, "sync-edge", &info->sync_edge);
+ ret |= of_property_read_u32(info_np, "sync-ctrl", &info->sync_ctrl);
+ ret |= of_property_read_u32(info_np, "raster-order", &info->raster_order);
+ ret |= of_property_read_u32(info_np, "fifo-th", &info->fifo_th);
+
+ /* optional: */
+ info->tft_alt_mode = of_property_read_bool(info_np, "tft-alt-mode");
+ info->stn_565_mode = of_property_read_bool(info_np, "stn-565-mode");
+ info->mono_8bit_mode = of_property_read_bool(info_np, "mono-8bit-mode");
+ info->invert_line_clock = of_property_read_bool(info_np, "invert-line-clock");
+ info->invert_frm_clock = of_property_read_bool(info_np, "invert-frm-clock");
+ info->invert_pxl_clk = of_property_read_bool(info_np, "invert-pxl-clk");
+
+ if (of_property_read_u32(info_np, "max-bpp", &info->max_bpp))
+ info->max_bpp = info->bpp;
+ if (of_property_read_u32(info_np, "min-bpp", &info->min_bpp))
+ info->min_bpp = info->bpp;
+
+ if (ret) {
+ pr_err("%s: error reading panel-info properties\n", __func__);
+ kfree(info);
+ return NULL;
+ }
+
+ return info;
+}
+
+static struct of_device_id panel_of_match[];
+
+static int __devinit panel_probe(struct platform_device *pdev)
+{
+ struct device_node *node = pdev->dev.of_node;
+ struct panel_module *panel_mod;
+ struct lcdc_module *mod;
+ struct pinctrl *pinctrl;
+ int ret = -EINVAL;
+
+ /* bail out early if no DT data: */
+ if (!of_match_device(panel_of_match, &pdev->dev)) {
+ dev_err(&pdev->dev, "device-tree data is missing\n");
+ return -ENXIO;
+ }
+
+ panel_mod = kzalloc(sizeof(*panel_mod), GFP_KERNEL);
+ if (!panel_mod)
+ return -ENOMEM;
+
+ mod = &panel_mod->base;
+
+ lcdc_module_init(mod, "panel", &panel_module_ops);
+
+ pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
+ if (IS_ERR(pinctrl))
+ dev_warn(&pdev->dev, "pins are not configured\n");
+
+
+ panel_mod->timings = of_get_display_timing_list(node);
+ if (!panel_mod->timings) {
+ dev_err(&pdev->dev, "could not get panel timings\n");
+ goto fail;
+ }
+
+ panel_mod->info = of_get_panel_info(node);
+ if (!panel_mod->info) {
+ dev_err(&pdev->dev, "could not get panel info\n");
+ goto fail;
+ }
+
+ return 0;
+
+fail:
+ panel_destroy(mod);
+ return ret;
+}
+
+static int __devexit panel_remove(struct platform_device *pdev)
+{
+ return 0;
+}
+
+static struct of_device_id panel_of_match[] = {
+ { .compatible = "lcdc,panel", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, panel_of_match);
+
+struct platform_driver panel_driver = {
+ .probe = panel_probe,
+ .remove = panel_remove,
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "panel",
+ .of_match_table = panel_of_match,
+ },
+};
+
+int __init lcdc_panel_init(void)
+{
+ return platform_driver_register(&panel_driver);
+}
+
+void __exit lcdc_panel_fini(void)
+{
+ platform_driver_unregister(&panel_driver);
+}
diff --git a/drivers/gpu/drm/lcdc/lcdc_panel.h b/drivers/gpu/drm/lcdc/lcdc_panel.h
new file mode 100644
index 0000000..44ce773
--- /dev/null
+++ b/drivers/gpu/drm/lcdc/lcdc_panel.h
@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2012 Texas Instruments
+ * Author: Rob Clark <robdclark@gmail.com>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __LCDC_PANEL_H__
+#define __LCDC_PANEL_H__
+
+/* sub-module for generic lcd panel output */
+
+int lcdc_panel_init(void);
+void lcdc_panel_fini(void);
+
+#endif /* __LCDC_PANEL_H__ */
--
1.8.0.2