Hi Hsin-Yi, thanks for the patch! Please fix the follow comment, then add my id. Reviewed-by: Xin Ji <xji@xxxxxxxxxxxxxxxx> On Tue, Jan 11, 2022 at 07:27:00PM +0800, Hsin-Yi Wang wrote: > Support reading edid through aux channel if panel is connected to aux > bus. Extend anx7625_aux_dpcd_trans() to implement aux transfer function: > > 1. panel is populated in devm_of_dp_aux_populate_ep_devices(), so move > anx7625_parse_dt() after. > 2. Use pm runtime autosuspend since aux transfer function is called > multiple times when reading edid. > 3. No-op if aux transfer length is 0. > > Signed-off-by: Hsin-Yi Wang <hsinyi@xxxxxxxxxxxx> > --- > This patch is based on drm-misc-next and depends on > https://patchwork.freedesktop.org/patch/469081/ > --- > drivers/gpu/drm/bridge/analogix/anx7625.c | 123 ++++++++++++++++++---- > drivers/gpu/drm/bridge/analogix/anx7625.h | 4 + > 2 files changed, 109 insertions(+), 18 deletions(-) > > diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c > index dbe708eb3bcf11..d60cfc058fbe7d 100644 > --- a/drivers/gpu/drm/bridge/analogix/anx7625.c > +++ b/drivers/gpu/drm/bridge/analogix/anx7625.c > @@ -24,6 +24,7 @@ > #include <drm/drm_atomic_helper.h> > #include <drm/drm_bridge.h> > #include <drm/drm_crtc_helper.h> > +#include <drm/drm_dp_aux_bus.h> > #include <drm/drm_dp_helper.h> > #include <drm/drm_edid.h> > #include <drm/drm_hdcp.h> > @@ -231,19 +232,22 @@ static int wait_aux_op_finish(struct anx7625_data *ctx) > return 0; > } > > -static int anx7625_aux_dpcd_trans(struct anx7625_data *ctx, u8 op, > - u32 address, u8 len, u8 *buf) > +static int anx7625_aux_trans(struct anx7625_data *ctx, u8 op, u32 address, > + u8 len, u8 *buf) > { > struct device *dev = &ctx->client->dev; > int ret; > u8 addrh, addrm, addrl; > u8 cmd; > > - if (len > MAX_DPCD_BUFFER_SIZE) { > + if (len > DP_AUX_MAX_PAYLOAD_BYTES) { > dev_err(dev, "exceed aux buffer len.\n"); > return -EINVAL; The native write command is 0x08, I2C Over aux write command is 0x04. The native read command is 0x09, I2C Over aux read command is 0x05. > } > > + if (!len) > + return len; > + > addrl = address & 0xFF; > addrm = (address >> 8) & 0xFF; > addrh = (address >> 16) & 0xFF; > @@ -262,7 +266,7 @@ static int anx7625_aux_dpcd_trans(struct anx7625_data *ctx, u8 op, > ret |= anx7625_reg_write(ctx, ctx->i2c.rx_p0_client, > AP_AUX_ADDR_19_16, addrh); > > - if (op == DPCD_WRITE) > + if (op == DPCD_WRITE || op == AP_AUX_WRITE) > ret |= anx7625_reg_block_write(ctx, ctx->i2c.rx_p0_client, > AP_AUX_BUFF_START, len, buf); > /* Enable aux access */ > @@ -275,14 +279,14 @@ static int anx7625_aux_dpcd_trans(struct anx7625_data *ctx, u8 op, > } > > ret = wait_aux_op_finish(ctx); > - if (ret) { > + if (ret < 0) { > dev_err(dev, "aux IO error: wait aux op finish.\n"); > return ret; > } > > /* Write done */ > - if (op == DPCD_WRITE) > - return 0; > + if (op == DPCD_WRITE || op == AP_AUX_WRITE) > + return len; > > /* Read done, read out dpcd data */ > ret = anx7625_reg_block_read(ctx, ctx->i2c.rx_p0_client, > @@ -292,7 +296,7 @@ static int anx7625_aux_dpcd_trans(struct anx7625_data *ctx, u8 op, > return -EIO; > } > > - return 0; > + return len; > } > > static int anx7625_video_mute_control(struct anx7625_data *ctx, > @@ -867,7 +871,7 @@ static int anx7625_hdcp_enable(struct anx7625_data *ctx) > } > > /* Read downstream capability */ > - anx7625_aux_dpcd_trans(ctx, DPCD_READ, 0x68028, 1, &bcap); > + anx7625_aux_trans(ctx, DPCD_READ, 0x68028, 1, &bcap); > if (!(bcap & 0x01)) { > pr_warn("downstream not support HDCP 1.4, cap(%x).\n", bcap); > return 0; > @@ -956,7 +960,7 @@ static void anx7625_dp_stop(struct anx7625_data *ctx) > dev_dbg(dev, "notify downstream enter into standby\n"); > /* Downstream monitor enter into standby mode */ > data = 2; > - ret |= anx7625_aux_dpcd_trans(ctx, DPCD_WRITE, 0x000600, 1, &data); > + ret |= anx7625_aux_trans(ctx, DPCD_WRITE, 0x000600, 1, &data); > if (ret < 0) > DRM_DEV_ERROR(dev, "IO error : mute video fail\n"); > > @@ -1655,11 +1659,60 @@ static int anx7625_parse_dt(struct device *dev, > return 0; > } > > +static bool anx7625_of_panel_on_aux_bus(struct device *dev) > +{ > + struct device_node *bus, *panel; > + > + bus = of_get_child_by_name(dev->of_node, "aux-bus"); > + if (!bus) > + return false; > + > + panel = of_get_child_by_name(bus, "panel"); > + of_node_put(bus); > + if (!panel) > + return false; > + of_node_put(panel); > + > + return true; > +} > + > static inline struct anx7625_data *bridge_to_anx7625(struct drm_bridge *bridge) > { > return container_of(bridge, struct anx7625_data, bridge); > } > > +static ssize_t anx7625_aux_transfer(struct drm_dp_aux *aux, > + struct drm_dp_aux_msg *msg) > +{ > + struct anx7625_data *ctx = container_of(aux, struct anx7625_data, aux); > + struct device *dev = &ctx->client->dev; > + u8 request = msg->request & ~DP_AUX_I2C_MOT, op; > + int ret = 0; > + > + pm_runtime_get_sync(dev); > + msg->reply = 0; > + switch (request) { > + case DP_AUX_NATIVE_WRITE: > + case DP_AUX_I2C_WRITE: > + op = AP_AUX_WRITE; The DPCD native write is different with I2C over aux write. > + break; > + case DP_AUX_NATIVE_READ: > + case DP_AUX_I2C_READ: > + op = AP_AUX_READ; The DPCD native read is different with I2C over aux read. > + break; > + default: > + ret = -EINVAL; > + } > + if (!ret) { > + ret = anx7625_aux_trans(ctx, op, msg->address, msg->size, > + msg->buffer); > + } > + pm_runtime_mark_last_busy(dev); > + pm_runtime_put_autosuspend(dev); > + > + return ret; > +} > + > static struct edid *anx7625_get_edid(struct anx7625_data *ctx) > { > struct device *dev = &ctx->client->dev; > @@ -2066,6 +2119,13 @@ static int anx7625_bridge_attach(struct drm_bridge *bridge, > return -ENODEV; > } > > + ctx->aux.drm_dev = bridge->dev; > + err = drm_dp_aux_register(&ctx->aux); > + if (err) { > + dev_err(dev, "failed to register aux channel: %d\n", err); > + return err; > + } > + > if (ctx->pdata.panel_bridge) { > err = drm_bridge_attach(bridge->encoder, > ctx->pdata.panel_bridge, > @@ -2079,6 +2139,13 @@ static int anx7625_bridge_attach(struct drm_bridge *bridge, > return 0; > } > > +static void anx7625_bridge_detach(struct drm_bridge *bridge) > +{ > + struct anx7625_data *ctx = bridge_to_anx7625(bridge); > + > + drm_dp_aux_unregister(&ctx->aux); > +} > + > static enum drm_mode_status > anx7625_bridge_mode_valid(struct drm_bridge *bridge, > const struct drm_display_info *info, > @@ -2344,6 +2411,7 @@ static struct edid *anx7625_bridge_get_edid(struct drm_bridge *bridge, > > static const struct drm_bridge_funcs anx7625_bridge_funcs = { > .attach = anx7625_bridge_attach, > + .detach = anx7625_bridge_detach, > .mode_valid = anx7625_bridge_mode_valid, > .mode_set = anx7625_bridge_mode_set, > .atomic_check = anx7625_bridge_atomic_check, > @@ -2501,6 +2569,12 @@ static const struct dev_pm_ops anx7625_pm_ops = { > anx7625_runtime_pm_resume, NULL) > }; > > +static void anx7625_runtime_disable(void *data) > +{ > + pm_runtime_dont_use_autosuspend(data); > + pm_runtime_disable(data); > +} > + > static int anx7625_i2c_probe(struct i2c_client *client, > const struct i2c_device_id *id) > { > @@ -2523,13 +2597,6 @@ static int anx7625_i2c_probe(struct i2c_client *client, > > pdata = &platform->pdata; > > - ret = anx7625_parse_dt(dev, pdata); > - if (ret) { > - if (ret != -EPROBE_DEFER) > - DRM_DEV_ERROR(dev, "fail to parse DT : %d\n", ret); > - return ret; > - } > - > platform->client = client; > i2c_set_clientdata(client, platform); > > @@ -2577,6 +2644,19 @@ static int anx7625_i2c_probe(struct i2c_client *client, > } > } > > + platform->aux.name = "anx7625-aux"; > + platform->aux.dev = dev; > + platform->aux.transfer = anx7625_aux_transfer; > + drm_dp_aux_init(&platform->aux); > + devm_of_dp_aux_populate_ep_devices(&platform->aux); > + > + ret = anx7625_parse_dt(dev, pdata); > + if (ret) { > + if (ret != -EPROBE_DEFER) > + DRM_DEV_ERROR(dev, "fail to parse DT : %d\n", ret); > + return ret; > + } > + > if (anx7625_register_i2c_dummy_clients(platform, client) != 0) { > ret = -ENOMEM; > DRM_DEV_ERROR(dev, "fail to reserve I2C bus.\n"); > @@ -2584,6 +2664,12 @@ static int anx7625_i2c_probe(struct i2c_client *client, > } > > pm_runtime_enable(dev); > + pm_runtime_set_autosuspend_delay(dev, 1000); > + pm_runtime_use_autosuspend(dev); > + pm_suspend_ignore_children(dev, true); > + ret = devm_add_action_or_reset(dev, anx7625_runtime_disable, dev); > + if (ret) > + return ret; > > if (!platform->pdata.low_power_mode) { > anx7625_disable_pd_protocol(platform); > @@ -2596,7 +2682,8 @@ static int anx7625_i2c_probe(struct i2c_client *client, > > platform->bridge.funcs = &anx7625_bridge_funcs; > platform->bridge.of_node = client->dev.of_node; > - platform->bridge.ops = DRM_BRIDGE_OP_EDID; > + if (!anx7625_of_panel_on_aux_bus(&client->dev)) > + platform->bridge.ops |= DRM_BRIDGE_OP_EDID; > if (!platform->pdata.panel_bridge) > platform->bridge.ops |= DRM_BRIDGE_OP_HPD | > DRM_BRIDGE_OP_DETECT; > diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.h b/drivers/gpu/drm/bridge/analogix/anx7625.h > index 56165f5b254c14..cab19735c22e21 100644 > --- a/drivers/gpu/drm/bridge/analogix/anx7625.h > +++ b/drivers/gpu/drm/bridge/analogix/anx7625.h > @@ -231,6 +231,9 @@ > #define AP_AUX_ADDR_15_8 0x12 > #define AP_AUX_ADDR_19_16 0x13 > > +#define AP_AUX_READ 0x1 > +#define AP_AUX_WRITE 0x4 > + > /* Bit[0:3] AUX status, bit 4 op_en, bit 5 address only */ > #define AP_AUX_CTRL_STATUS 0x14 > #define AP_AUX_CTRL_OP_EN 0x10 > @@ -474,6 +477,7 @@ struct anx7625_data { > u8 bridge_attached; > struct drm_connector *connector; > struct mipi_dsi_device *dsi; > + struct drm_dp_aux aux; > }; > > #endif /* __ANX7625_H__ */ > -- > 2.34.1.575.g55b058a8bb-goog