diff options
Diffstat (limited to 'drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_output.c')
| -rw-r--r-- | drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_output.c | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_output.c b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_output.c new file mode 100644 index 000000000..50fee6a93 --- /dev/null +++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_output.c @@ -0,0 +1,150 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2014 Traphandler + * Copyright (C) 2014 Free Electrons + * Copyright (C) 2014 Atmel + * + * Author: Jean-Jacques Hiblot <jjhiblot@traphandler.com> + * Author: Boris BREZILLON <boris.brezillon@free-electrons.com> + */ + +#include <linux/media-bus-format.h> +#include <linux/of.h> +#include <linux/of_graph.h> + +#include <drm/drm_bridge.h> +#include <drm/drm_encoder.h> +#include <drm/drm_of.h> +#include <drm/drm_simple_kms_helper.h> + +#include "atmel_hlcdc_dc.h" + +struct atmel_hlcdc_rgb_output { + struct drm_encoder encoder; + int bus_fmt; +}; + +static struct atmel_hlcdc_rgb_output * +atmel_hlcdc_encoder_to_rgb_output(struct drm_encoder *encoder) +{ + return container_of(encoder, struct atmel_hlcdc_rgb_output, encoder); +} + +int atmel_hlcdc_encoder_get_bus_fmt(struct drm_encoder *encoder) +{ + struct atmel_hlcdc_rgb_output *output; + + output = atmel_hlcdc_encoder_to_rgb_output(encoder); + + return output->bus_fmt; +} + +static int atmel_hlcdc_of_bus_fmt(const struct device_node *ep) +{ + u32 bus_width; + int ret; + + ret = of_property_read_u32(ep, "bus-width", &bus_width); + if (ret == -EINVAL) + return 0; + if (ret) + return ret; + + switch (bus_width) { + case 12: + return MEDIA_BUS_FMT_RGB444_1X12; + case 16: + return MEDIA_BUS_FMT_RGB565_1X16; + case 18: + return MEDIA_BUS_FMT_RGB666_1X18; + case 24: + return MEDIA_BUS_FMT_RGB888_1X24; + default: + return -EINVAL; + } +} + +static int atmel_hlcdc_attach_endpoint(struct drm_device *dev, int endpoint) +{ + struct atmel_hlcdc_rgb_output *output; + struct device_node *ep; + struct drm_panel *panel; + struct drm_bridge *bridge; + int ret; + + ep = of_graph_get_endpoint_by_regs(dev->dev->of_node, 0, endpoint); + if (!ep) + return -ENODEV; + + ret = drm_of_find_panel_or_bridge(dev->dev->of_node, 0, endpoint, + &panel, &bridge); + if (ret) { + of_node_put(ep); + return ret; + } + + output = devm_kzalloc(dev->dev, sizeof(*output), GFP_KERNEL); + if (!output) { + of_node_put(ep); + return -ENOMEM; + } + + output->bus_fmt = atmel_hlcdc_of_bus_fmt(ep); + of_node_put(ep); + if (output->bus_fmt < 0) { + dev_err(dev->dev, "endpoint %d: invalid bus width\n", endpoint); + return -EINVAL; + } + + ret = drm_simple_encoder_init(dev, &output->encoder, + DRM_MODE_ENCODER_NONE); + if (ret) + return ret; + + output->encoder.possible_crtcs = 0x1; + + if (panel) { + bridge = drm_panel_bridge_add_typed(panel, + DRM_MODE_CONNECTOR_Unknown); + if (IS_ERR(bridge)) + return PTR_ERR(bridge); + } + + if (bridge) { + ret = drm_bridge_attach(&output->encoder, bridge, NULL, 0); + if (!ret) + return 0; + + if (panel) + drm_panel_bridge_remove(bridge); + } + + drm_encoder_cleanup(&output->encoder); + + return ret; +} + +int atmel_hlcdc_create_outputs(struct drm_device *dev) +{ + int endpoint, ret = 0; + int attached = 0; + + /* + * Always scan the first few endpoints even if we get -ENODEV, + * but keep going after that as long as we keep getting hits. + */ + for (endpoint = 0; !ret || endpoint < 4; endpoint++) { + ret = atmel_hlcdc_attach_endpoint(dev, endpoint); + if (ret == -ENODEV) + continue; + if (ret) + break; + attached++; + } + + /* At least one device was successfully attached.*/ + if (ret == -ENODEV && attached) + return 0; + + return ret; +} |