Quelle  imx8qxp-pxl2dpi.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0+

/*
 * Copyright 2020 NXP
 */

#include <linux/firmware/imx/svc/misc.h>
#include <linux/media-bus-format.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,
      struct drm_encoder *encoder,
      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;
 }

 return drm_bridge_attach(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_atomic_state *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, 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_drm_bridge_alloc(dev, struct imx8qxp_pxl2dpi, bridge,
        &imx8qxp_pxl2dpi_bridge_funcs);
 if (IS_ERR(p2d))
  return PTR_ERR(p2d);

 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.of_node = np;

 drm_bridge_add(&p2d->bridge);

 return ret;
}

static void 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);
}

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 ");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:" DRIVER_NAME);