[PATCH v8 08/14] drm/bridge: imx: Add i.MX8qxp pixel link to DPI support

Liu Ying
2022-06-09T06:49:24Z

This patch adds a drm bridge driver for i.MX8qxp pixel link to display
pixel interface(PXL2DPI). The PXL2DPI interfaces the pixel link 36-bit
data output and the DSI controller’s MIPI-DPI 24-bit data input, and
inputs of LVDS Display Bridge(LDB) module used in LVDS mode, to remap
the pixel color codings between those modules. The PXL2DPI is purely
combinatorial.

Tested-by: Marcel Ziswiler <marcel.ziswiler@toradex.com> # Colibri iMX8X, LT170410-2WHC, LP156WF1
Reviewed-by: Robert Foss <robert.foss@linaro.org>
Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
Marcel, I add your T-b tag from v6, let me know if you want me to drop it, as
the checkpatch fix and indentation fix in v7 are trivial.

v7->v8:
* No change.

v6->v7:
* Fix below complaints from 'checkpatch.pl --strict'. (Robert)
- 'Alignment should match open parenthesis'
- 'ENOTSUPP is not a SUSV4 error code, prefer EOPNOTSUPP'
* A trivial indentation fix. (Robert)
* Add Marcel's T-b tag.
* Add Robert's R-b tag.

v5->v6:
* No change.

v4->v5:
* No change.

v3->v4:
* Use 'fsl,sc-resource' DT property to get the SCU resource ID associated with
the PXL2DPI instance instead of using alias ID. (Rob)

v2->v3:
* Call syscon_node_to_regmap() to get regmap instead of
syscon_regmap_lookup_by_phandle().

v1->v2:
* Drop unnecessary port availability check.

drivers/gpu/drm/bridge/imx/Kconfig | 8 +
drivers/gpu/drm/bridge/imx/Makefile | 1 +
drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c | 487 +++++++++++++++++++
3 files changed, 496 insertions(+)
create mode 100644 drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c

diff --git a/drivers/gpu/drm/bridge/imx/Kconfig b/drivers/gpu/drm/bridge/imx/Kconfig
index 4d1f027d07f8..1ea1ce7f558c 100644
--- a/drivers/gpu/drm/bridge/imx/Kconfig
+++ b/drivers/gpu/drm/bridge/imx/Kconfig
@@ -14,3 +14,11 @@ config DRM_IMX8QXP_PIXEL_LINK
help
Choose this to enable display pixel link found in
Freescale i.MX8qm/qxp processors.
+
+config DRM_IMX8QXP_PIXEL_LINK_TO_DPI
+ tristate "Freescale i.MX8QXP pixel link to display pixel interface"
+ depends on OF
+ select DRM_KMS_HELPER
+ help
+ Choose this to enable pixel link to display pixel interface(PXL2DPI)
+ found in Freescale i.MX8qxp processor.
diff --git a/drivers/gpu/drm/bridge/imx/Makefile b/drivers/gpu/drm/bridge/imx/Makefile
index c15469fb5789..e74dd6422e95 100644
--- a/drivers/gpu/drm/bridge/imx/Makefile
+++ b/drivers/gpu/drm/bridge/imx/Makefile
@@ -1,2 +1,3 @@
obj-$(CONFIG_DRM_IMX8QXP_PIXEL_COMBINER) += imx8qxp-pixel-combiner.o
obj-$(CONFIG_DRM_IMX8QXP_PIXEL_LINK) += imx8qxp-pixel-link.o
+obj-$(CONFIG_DRM_IMX8QXP_PIXEL_LINK_TO_DPI) += imx8qxp-pxl2dpi.o
diff --git a/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c b/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c
new file mode 100644
index 000000000000..309f47a14cb6
--- /dev/null
+++ b/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c
@@ -0,0 +1,487 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+/*
+ * Copyright 2020 NXP
+ */
+
+#include <linux/firmware/imx/svc/misc.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_graph.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+
+#include <drm/drm_atomic_state_helper.h>
+#include <drm/drm_bridge.h>
+#include <drm/drm_of.h>
+#include <drm/drm_print.h>
+
+#include <dt-bindings/firmware/imx/rsrc.h>
+
+#define PXL2DPI_CTRL 0x40
+#define CFG1_16BIT 0x0
+#define CFG2_16BIT 0x1
+#define CFG3_16BIT 0x2
+#define CFG1_18BIT 0x3
+#define CFG2_18BIT 0x4
+#define CFG_24BIT 0x5
+
+#define DRIVER_NAME "imx8qxp-pxl2dpi"
+
+struct imx8qxp_pxl2dpi {
+ struct regmap *regmap;
+ struct drm_bridge bridge;
+ struct drm_bridge *next_bridge;
+ struct drm_bridge *companion;
+ struct device *dev;
+ struct imx_sc_ipc *ipc_handle;
+ u32 sc_resource;
+ u32 in_bus_format;
+ u32 out_bus_format;
+ u32 pl_sel;
+};
+
+#define bridge_to_p2d(b) container_of(b, struct imx8qxp_pxl2dpi, bridge)
+
+static int imx8qxp_pxl2dpi_bridge_attach(struct drm_bridge *bridge,
+ enum drm_bridge_attach_flags flags)
+{
+ struct imx8qxp_pxl2dpi *p2d = bridge->driver_private;
+
+ if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)) {
+ DRM_DEV_ERROR(p2d->dev,
+ "do not support creating a drm_connector\n");
+ return -EINVAL;
+ }
+
+ if (!bridge->encoder) {
+ DRM_DEV_ERROR(p2d->dev, "missing encoder\n");
+ return -ENODEV;
+ }
+
+ return drm_bridge_attach(bridge->encoder,
+ p2d->next_bridge, bridge,
+ DRM_BRIDGE_ATTACH_NO_CONNECTOR);
+}
+
+static int
+imx8qxp_pxl2dpi_bridge_atomic_check(struct drm_bridge *bridge,
+ struct drm_bridge_state *bridge_state,
+ struct drm_crtc_state *crtc_state,
+ struct drm_connector_state *conn_state)
+{
+ struct imx8qxp_pxl2dpi *p2d = bridge->driver_private;
+
+ p2d->in_bus_format = bridge_state->input_bus_cfg.format;
+ p2d->out_bus_format = bridge_state->output_bus_cfg.format;
+
+ return 0;
+}
+
+static void
+imx8qxp_pxl2dpi_bridge_mode_set(struct drm_bridge *bridge,
+ const struct drm_display_mode *mode,
+ const struct drm_display_mode *adjusted_mode)
+{
+ struct imx8qxp_pxl2dpi *p2d = bridge->driver_private;
+ struct imx8qxp_pxl2dpi *companion_p2d;
+ int ret;
+
+ ret = pm_runtime_get_sync(p2d->dev);
+ if (ret < 0)
+ DRM_DEV_ERROR(p2d->dev,
+ "failed to get runtime PM sync: %d\n", ret);
+
+ ret = imx_sc_misc_set_control(p2d->ipc_handle, p2d->sc_resource,
+ IMX_SC_C_PXL_LINK_SEL, p2d->pl_sel);
+ if (ret)
+ DRM_DEV_ERROR(p2d->dev,
+ "failed to set pixel link selection(%u): %d\n",
+ p2d->pl_sel, ret);
+
+ switch (p2d->out_bus_format) {
+ case MEDIA_BUS_FMT_RGB888_1X24:
+ regmap_write(p2d->regmap, PXL2DPI_CTRL, CFG_24BIT);
+ break;
+ case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
+ regmap_write(p2d->regmap, PXL2DPI_CTRL, CFG2_18BIT);
+ break;
+ default:
+ DRM_DEV_ERROR(p2d->dev,
+ "unsupported output bus format 0x%08x\n",
+ p2d->out_bus_format);
+ }
+
+ if (p2d->companion) {
+ companion_p2d = bridge_to_p2d(p2d->companion);
+
+ companion_p2d->in_bus_format = p2d->in_bus_format;
+ companion_p2d->out_bus_format = p2d->out_bus_format;
+
+ p2d->companion->funcs->mode_set(p2d->companion, mode,
+ adjusted_mode);
+ }
+}
+
+static void
+imx8qxp_pxl2dpi_bridge_atomic_disable(struct drm_bridge *bridge,
+ struct drm_bridge_state *old_bridge_state)
+{
+ struct imx8qxp_pxl2dpi *p2d = bridge->driver_private;
+ int ret;
+
+ ret = pm_runtime_put(p2d->dev);
+ if (ret < 0)
+ DRM_DEV_ERROR(p2d->dev, "failed to put runtime PM: %d\n", ret);
+
+ if (p2d->companion)
+ p2d->companion->funcs->atomic_disable(p2d->companion,
+ old_bridge_state);
+}
+
+static const u32 imx8qxp_pxl2dpi_bus_output_fmts[] = {
+ MEDIA_BUS_FMT_RGB888_1X24,
+ MEDIA_BUS_FMT_RGB666_1X24_CPADHI,
+};
+
+static bool imx8qxp_pxl2dpi_bus_output_fmt_supported(u32 fmt)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(imx8qxp_pxl2dpi_bus_output_fmts); i++) {
+ if (imx8qxp_pxl2dpi_bus_output_fmts[i] == fmt)
+ return true;
+ }
+
+ return false;
+}
+
+static u32 *
+imx8qxp_pxl2dpi_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
+ struct drm_bridge_state *bridge_state,
+ struct drm_crtc_state *crtc_state,
+ struct drm_connector_state *conn_state,
+ u32 output_fmt,
+ unsigned int *num_input_fmts)
+{
+ u32 *input_fmts;
+
+ if (!imx8qxp_pxl2dpi_bus_output_fmt_supported(output_fmt))
+ return NULL;
+
+ *num_input_fmts = 1;
+
+ input_fmts = kmalloc(sizeof(*input_fmts), GFP_KERNEL);
+ if (!input_fmts)
+ return NULL;
+
+ switch (output_fmt) {
+ case MEDIA_BUS_FMT_RGB888_1X24:
+ input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X36_CPADLO;
+ break;
+ case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
+ input_fmts[0] = MEDIA_BUS_FMT_RGB666_1X36_CPADLO;
+ break;
+ default:
+ kfree(input_fmts);
+ input_fmts = NULL;
+ break;
+ }
+
+ return input_fmts;
+}
+
+static u32 *
+imx8qxp_pxl2dpi_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge,
+ struct drm_bridge_state *bridge_state,
+ struct drm_crtc_state *crtc_state,
+ struct drm_connector_state *conn_state,
+ unsigned int *num_output_fmts)
+{
+ *num_output_fmts = ARRAY_SIZE(imx8qxp_pxl2dpi_bus_output_fmts);
+ return kmemdup(imx8qxp_pxl2dpi_bus_output_fmts,
+ sizeof(imx8qxp_pxl2dpi_bus_output_fmts), GFP_KERNEL);
+}
+
+static const struct drm_bridge_funcs imx8qxp_pxl2dpi_bridge_funcs = {
+ .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
+ .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
+ .atomic_reset = drm_atomic_helper_bridge_reset,
+ .attach = imx8qxp_pxl2dpi_bridge_attach,
+ .atomic_check = imx8qxp_pxl2dpi_bridge_atomic_check,
+ .mode_set = imx8qxp_pxl2dpi_bridge_mode_set,
+ .atomic_disable = imx8qxp_pxl2dpi_bridge_atomic_disable,
+ .atomic_get_input_bus_fmts =
+ imx8qxp_pxl2dpi_bridge_atomic_get_input_bus_fmts,
+ .atomic_get_output_bus_fmts =
+ imx8qxp_pxl2dpi_bridge_atomic_get_output_bus_fmts,
+};
+
+static struct device_node *
+imx8qxp_pxl2dpi_get_available_ep_from_port(struct imx8qxp_pxl2dpi *p2d,
+ u32 port_id)
+{
+ struct device_node *port, *ep;
+ int ep_cnt;
+
+ port = of_graph_get_port_by_id(p2d->dev->of_node, port_id);
+ if (!port) {
+ DRM_DEV_ERROR(p2d->dev, "failed to get port@%u\n", port_id);
+ return ERR_PTR(-ENODEV);
+ }
+
+ ep_cnt = of_get_available_child_count(port);
+ if (ep_cnt == 0) {
+ DRM_DEV_ERROR(p2d->dev, "no available endpoints of port@%u\n",
+ port_id);
+ ep = ERR_PTR(-ENODEV);
+ goto out;
+ } else if (ep_cnt > 1) {
+ DRM_DEV_ERROR(p2d->dev,
+ "invalid available endpoints of port@%u\n",
+ port_id);
+ ep = ERR_PTR(-EINVAL);
+ goto out;
+ }
+
+ ep = of_get_next_available_child(port, NULL);
+ if (!ep) {
+ DRM_DEV_ERROR(p2d->dev,
+ "failed to get available endpoint of port@%u\n",
+ port_id);
+ ep = ERR_PTR(-ENODEV);
+ goto out;
+ }
+out:
+ of_node_put(port);
+ return ep;
+}
+
+static struct drm_bridge *
+imx8qxp_pxl2dpi_find_next_bridge(struct imx8qxp_pxl2dpi *p2d)
+{
+ struct device_node *ep, *remote;
+ struct drm_bridge *next_bridge;
+ int ret;
+
+ ep = imx8qxp_pxl2dpi_get_available_ep_from_port(p2d, 1);
+ if (IS_ERR(ep)) {
+ ret = PTR_ERR(ep);
+ return ERR_PTR(ret);
+ }
+
+ remote = of_graph_get_remote_port_parent(ep);
+ if (!remote || !of_device_is_available(remote)) {
+ DRM_DEV_ERROR(p2d->dev, "no available remote\n");
+ next_bridge = ERR_PTR(-ENODEV);
+ goto out;
+ } else if (!of_device_is_available(remote->parent)) {
+ DRM_DEV_ERROR(p2d->dev, "remote parent is not available\n");
+ next_bridge = ERR_PTR(-ENODEV);
+ goto out;
+ }
+
+ next_bridge = of_drm_find_bridge(remote);
+ if (!next_bridge) {
+ next_bridge = ERR_PTR(-EPROBE_DEFER);
+ goto out;
+ }
+out:
+ of_node_put(remote);
+ of_node_put(ep);
+
+ return next_bridge;
+}
+
+static int imx8qxp_pxl2dpi_set_pixel_link_sel(struct imx8qxp_pxl2dpi *p2d)
+{
+ struct device_node *ep;
+ struct of_endpoint endpoint;
+ int ret;
+
+ ep = imx8qxp_pxl2dpi_get_available_ep_from_port(p2d, 0);
+ if (IS_ERR(ep))
+ return PTR_ERR(ep);
+
+ ret = of_graph_parse_endpoint(ep, &endpoint);
+ if (ret) {
+ DRM_DEV_ERROR(p2d->dev,
+ "failed to parse endpoint of port@0: %d\n", ret);
+ goto out;
+ }
+
+ p2d->pl_sel = endpoint.id;
+out:
+ of_node_put(ep);
+
+ return ret;
+}
+
+static int imx8qxp_pxl2dpi_parse_dt_companion(struct imx8qxp_pxl2dpi *p2d)
+{
+ struct imx8qxp_pxl2dpi *companion_p2d;
+ struct device *dev = p2d->dev;
+ struct device_node *companion;
+ struct device_node *port1, *port2;
+ const struct of_device_id *match;
+ int dual_link;
+ int ret = 0;
+
+ /* Locate the companion PXL2DPI for dual-link operation, if any. */
+ companion = of_parse_phandle(dev->of_node, "fsl,companion-pxl2dpi", 0);
+ if (!companion)
+ return 0;
+
+ if (!of_device_is_available(companion)) {
+ DRM_DEV_ERROR(dev, "companion PXL2DPI is not available\n");
+ ret = -ENODEV;
+ goto out;
+ }
+
+ /*
+ * Sanity check: the companion bridge must have the same compatible
+ * string.
+ */
+ match = of_match_device(dev->driver->of_match_table, dev);
+ if (!of_device_is_compatible(companion, match->compatible)) {
+ DRM_DEV_ERROR(dev, "companion PXL2DPI is incompatible\n");
+ ret = -ENXIO;
+ goto out;
+ }
+
+ p2d->companion = of_drm_find_bridge(companion);
+ if (!p2d->companion) {
+ ret = -EPROBE_DEFER;
+ DRM_DEV_DEBUG_DRIVER(p2d->dev,
+ "failed to find companion bridge: %d\n",
+ ret);
+ goto out;
+ }
+
+ companion_p2d = bridge_to_p2d(p2d->companion);
+
+ /*
+ * We need to work out if the sink is expecting us to function in
+ * dual-link mode. We do this by looking at the DT port nodes that
+ * the next bridges are connected to. If they are marked as expecting
+ * even pixels and odd pixels than we need to use the companion PXL2DPI.
+ */
+ port1 = of_graph_get_port_by_id(p2d->next_bridge->of_node, 1);
+ port2 = of_graph_get_port_by_id(companion_p2d->next_bridge->of_node, 1);
+ dual_link = drm_of_lvds_get_dual_link_pixel_order(port1, port2);
+ of_node_put(port1);
+ of_node_put(port2);
+
+ if (dual_link < 0) {
+ ret = dual_link;
+ DRM_DEV_ERROR(dev, "failed to get dual link pixel order: %d\n",
+ ret);
+ goto out;
+ }
+
+ DRM_DEV_DEBUG_DRIVER(dev,
+ "dual-link configuration detected (companion bridge %pOF)\n",
+ companion);
+out:
+ of_node_put(companion);
+ return ret;
+}
+
+static int imx8qxp_pxl2dpi_bridge_probe(struct platform_device *pdev)
+{
+ struct imx8qxp_pxl2dpi *p2d;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ int ret;
+
+ p2d = devm_kzalloc(dev, sizeof(*p2d), GFP_KERNEL);
+ if (!p2d)
+ return -ENOMEM;
+
+ p2d->regmap = syscon_node_to_regmap(np->parent);
+ if (IS_ERR(p2d->regmap)) {
+ ret = PTR_ERR(p2d->regmap);
+ if (ret != -EPROBE_DEFER)
+ DRM_DEV_ERROR(dev, "failed to get regmap: %d\n", ret);
+ return ret;
+ }
+
+ ret = imx_scu_get_handle(&p2d->ipc_handle);
+ if (ret) {
+ if (ret != -EPROBE_DEFER)
+ DRM_DEV_ERROR(dev, "failed to get SCU ipc handle: %d\n",
+ ret);
+ return ret;
+ }
+
+ p2d->dev = dev;
+
+ ret = of_property_read_u32(np, "fsl,sc-resource", &p2d->sc_resource);
+ if (ret) {
+ DRM_DEV_ERROR(dev, "failed to get SC resource %d\n", ret);
+ return ret;
+ }
+
+ p2d->next_bridge = imx8qxp_pxl2dpi_find_next_bridge(p2d);
+ if (IS_ERR(p2d->next_bridge)) {
+ ret = PTR_ERR(p2d->next_bridge);
+ if (ret != -EPROBE_DEFER)
+ DRM_DEV_ERROR(dev, "failed to find next bridge: %d\n",
+ ret);
+ return ret;
+ }
+
+ ret = imx8qxp_pxl2dpi_set_pixel_link_sel(p2d);
+ if (ret)
+ return ret;
+
+ ret = imx8qxp_pxl2dpi_parse_dt_companion(p2d);
+ if (ret)
+ return ret;
+
+ platform_set_drvdata(pdev, p2d);
+ pm_runtime_enable(dev);
+
+ p2d->bridge.driver_private = p2d;
+ p2d->bridge.funcs = &imx8qxp_pxl2dpi_bridge_funcs;
+ p2d->bridge.of_node = np;
+
+ drm_bridge_add(&p2d->bridge);
+
+ return ret;
+}
+
+static int imx8qxp_pxl2dpi_bridge_remove(struct platform_device *pdev)
+{
+ struct imx8qxp_pxl2dpi *p2d = platform_get_drvdata(pdev);
+
+ drm_bridge_remove(&p2d->bridge);
+
+ pm_runtime_disable(&pdev->dev);
+
+ return 0;
+}
+
+static const struct of_device_id imx8qxp_pxl2dpi_dt_ids[] = {
+ { .compatible = "fsl,imx8qxp-pxl2dpi", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx8qxp_pxl2dpi_dt_ids);
+
+static struct platform_driver imx8qxp_pxl2dpi_bridge_driver = {
+ .probe = imx8qxp_pxl2dpi_bridge_probe,
+ .remove = imx8qxp_pxl2dpi_bridge_remove,
+ .driver = {
+ .of_match_table = imx8qxp_pxl2dpi_dt_ids,
+ .name = DRIVER_NAME,
+ },
+};
+module_platform_driver(imx8qxp_pxl2dpi_bridge_driver);
+
+MODULE_DESCRIPTION("i.MX8QXP pixel link to DPI bridge driver");
+MODULE_AUTHOR("Liu Ying <victor.liu@nxp.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" DRIVER_NAME);
--
2.25.1