diff options
Diffstat (limited to 'drivers/gpu/drm/arm/hdlcd_hdmi_encoder.c')
| -rw-r--r-- | drivers/gpu/drm/arm/hdlcd_hdmi_encoder.c | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/drivers/gpu/drm/arm/hdlcd_hdmi_encoder.c b/drivers/gpu/drm/arm/hdlcd_hdmi_encoder.c new file mode 100644 index 000000000000..5f6a4b4ff9f6 --- /dev/null +++ b/drivers/gpu/drm/arm/hdlcd_hdmi_encoder.c @@ -0,0 +1,236 @@ +/* + * Copyright (C) 2013,2014 ARM Limited + * Author: Liviu Dudau <Liviu.Dudau@arm.com> + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive + * for more details. + * + */ + +/* + * Theory of operation: + * + * The DRM framework expects the CRTC -> Encoder -> Connector chain, + * where the CRTC is reading from framebuffer, passes data to the + * encoder and that formats the signals to something usable by the + * attached connector(s). Connectors can use i2c links to talk with + * attached monitors. + * + * The HDMI transmitter is a different beast: it is both and encoder + * and a connector in DRM parlance *and* can only be reached via i2c. + * It implements an i2c pass through mode for the situation where one + * wants to talk with the attached monitor. To complicate things + * even further, the VExpress boards that have the SiI9022 chip share + * the i2c line between the on-board microcontroller and the CoreTiles. + * This leads to a situation where the microcontroller might be able to + * talk with the SiI9022 transmitter, but not the CoreTile. And the + * micro has a very small brain and a list of hardcoded modes that + * it can program into the HDMI transmitter, so only a limited set + * of resolutions will be valid. + * + * This file handles only the case where the i2c connection is available + * to the kernel. For the case where we have to ask the microcontroller + * to do the modesetting for us see the hdlcd_vexpress_encoder.c file. + */ + +#include <linux/i2c.h> +#include <drm/drmP.h> +#include <drm/drm_crtc_helper.h> +#include <drm/drm_encoder_slave.h> +#include <drm/i2c/tda998x.h> +#include <video/display_timing.h> +#include <video/of_display_timing.h> +#include <video/videomode.h> + +#include "hdlcd_drv.h" + +static inline struct drm_encoder_slave * +hdlcd_get_slave_encoder(struct drm_connector * connector) +{ + return to_encoder_slave(hdlcd_connector_best_encoder(connector)); +} + +static void hdlcd_connector_destroy(struct drm_connector *connector) +{ +} + +static enum drm_connector_status +hdlcd_connector_detect(struct drm_connector *connector, bool force) +{ + struct drm_encoder_slave *slave; + if (!connector->encoder) + connector->encoder = hdlcd_connector_best_encoder(connector); + + slave = hdlcd_get_slave_encoder(connector); + if (!slave || !slave->slave_funcs) + return connector_status_unknown; + + return slave->slave_funcs->detect(connector->encoder, connector); +} + +static const struct drm_connector_funcs hdlcd_connector_funcs = { + .destroy = hdlcd_connector_destroy, + .dpms = drm_helper_connector_dpms, + .detect = hdlcd_connector_detect, + .fill_modes = drm_helper_probe_single_connector_modes, +}; + +struct drm_encoder * +hdlcd_connector_best_encoder(struct drm_connector *connector) +{ + int enc_id = connector->encoder_ids[0]; + struct drm_mode_object *obj; + struct drm_encoder *encoder; + + if (connector->encoder) + return connector->encoder; + + if (enc_id) { + obj = drm_mode_object_find(connector->dev, enc_id, + DRM_MODE_OBJECT_ENCODER); + if (obj) { + encoder = obj_to_encoder(obj); + return encoder; + } + } + return NULL; + +} + +static int hdlcd_hdmi_con_get_modes(struct drm_connector *connector) +{ + struct drm_encoder_slave *slave = hdlcd_get_slave_encoder(connector); + + if (slave && slave->slave_funcs) + return slave->slave_funcs->get_modes(&slave->base, connector); + + return 0; +} + +static int hdlcd_hdmi_con_mode_valid(struct drm_connector *connector, + struct drm_display_mode *mode) +{ + struct drm_encoder_slave *slave = hdlcd_get_slave_encoder(connector); + + if (slave && slave->slave_funcs) + return slave->slave_funcs->mode_valid(connector->encoder, mode); + + return MODE_ERROR; +} + +static const struct drm_connector_helper_funcs hdlcd_hdmi_con_helper_funcs = { + .get_modes = hdlcd_hdmi_con_get_modes, + .mode_valid = hdlcd_hdmi_con_mode_valid, + .best_encoder = hdlcd_connector_best_encoder, +}; + + +static struct drm_encoder_funcs hdlcd_encoder_funcs = { + .destroy = drm_i2c_encoder_destroy, +}; + +static void hdlcd_hdmi_encoder_disable(struct drm_encoder *encoder) +{ + drm_i2c_encoder_dpms(encoder, DRM_MODE_DPMS_OFF); +} + +static struct drm_encoder_helper_funcs hdlcd_encoder_helper_funcs = { + .dpms = drm_i2c_encoder_dpms, + .save = drm_i2c_encoder_save, + .restore = drm_i2c_encoder_restore, + .mode_fixup = drm_i2c_encoder_mode_fixup, + .prepare = drm_i2c_encoder_prepare, + .commit = drm_i2c_encoder_commit, + .mode_set = drm_i2c_encoder_mode_set, + .detect = drm_i2c_encoder_detect, + .disable = hdlcd_hdmi_encoder_disable, +}; + +static struct tda998x_encoder_params tda998x_params = { + .swap_a = 2, + .swap_b = 3, + .swap_c = 4, + .swap_d = 5, + .swap_e = 0, + .swap_f = 1, +}; + +int hdlcd_create_digital_connector(struct drm_device *dev, + struct hdlcd_drm_private *hdlcd) +{ + int err; + struct i2c_board_info i2c_info; + struct drm_encoder_slave *slave; + struct drm_connector *connector; + struct device_node *node = hdlcd->slave_node; + + slave = kzalloc(sizeof(*slave), GFP_KERNEL); + if (!slave) + return -ENOMEM; + + slave->base.possible_crtcs = 1; + slave->base.possible_clones = 0; + + err = drm_encoder_init(dev, &slave->base, &hdlcd_encoder_funcs, + DRM_MODE_ENCODER_TMDS); + if (err) + goto encoder_init_err; + + drm_encoder_helper_add(&slave->base, &hdlcd_encoder_helper_funcs); + + /* get the driver for the i2c slave node */ + i2c_info.of_node = node; + err = of_modalias_node(node, i2c_info.type, sizeof(i2c_info.type)); + if (err < 0) { + dev_err(dev->dev, "failed to get a module alias for node %s\n", + node->full_name); + } + + /* Hack: this needs to be specified in the device tree */ + i2c_info.platform_data = &tda998x_params; + + err = drm_i2c_encoder_init(dev, slave, NULL, &i2c_info); + of_node_put(node); + if (err) + goto connector_alloc_err; + + connector = kzalloc(sizeof(*connector), GFP_KERNEL); + if (!connector) { + err = -ENOMEM; + goto connector_alloc_err; + } + + connector->interlace_allowed = false; + connector->doublescan_allowed = false; + connector->polled = DRM_CONNECTOR_POLL_CONNECT | + DRM_CONNECTOR_POLL_DISCONNECT; + err = drm_connector_init(dev, connector, &hdlcd_connector_funcs, + DRM_MODE_CONNECTOR_DVID); + if (err) + goto connector_init_err; + + drm_connector_helper_add(connector, &hdlcd_hdmi_con_helper_funcs); + + connector->encoder = &slave->base; + err = drm_mode_connector_attach_encoder(connector, &slave->base); + if (err) { + goto connector_attach_err; + } + + drm_sysfs_connector_add(connector); + + slave->base.dev->dev->platform_data = hdlcd; + return err; + +connector_attach_err: + drm_connector_cleanup(connector); +connector_init_err: + kfree(connector); +connector_alloc_err: + drm_encoder_cleanup(&slave->base); +encoder_init_err: + kfree(slave); + + return err; +} |