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authorAdrian Betschart <adrian.betschart@cinemaone.ch>2026-09-11 17:13:14 +0200
committerAlex Deucher <alexander.deucher@amd.com>2026-10-01 17:18:05 -0400
commit106b4a2a78b2a2f14885604891957b84bba502db (patch)
tree5d40eef2428fb1a4791ab46a4b19091a5910eac2 /drivers/phy/phy-can-transceiver.c
downloadlinux-stable-106b4a2a78b2a2f14885604891957b84bba502db.tar.gz
linux-stable-106b4a2a78b2a2f14885604891957b84bba502db.zip
drm/amd/display: Try RGB before YCbCr 4:4:4 in stream validationgrafted
amdgpu_dm_create_validate_stream_for_sink() walks encoding_order[] and uses the first encoding that validates. YCbCr 4:4:4 is listed before RGB, so an HDMI sink that advertises 4:4:4 gets YCbCr 4:4:4 whenever the "color format" property is left at AUTO, even though RGB fits the same link. That contradicts the documented AUTO behaviour for HDMI in enum drm_connector_color_format (RGB, falling back to YCbCr 4:2:0 only when the bandwidth is not available or the mode is 4:2:0-only), which the amdgpu implementation of the property also describes. It also leaves the "Broadcast RGB" property without effect on such sinks, since the quantization range it selects only applies to RGB output. Try RGB first. The mask still holds every encoding the sink supports, so a mode that cannot carry RGB falls back exactly as before. For reference, v7.2 picked RGB here unless YCbCr 4:4:4 was forced through debugfs, while earlier kernels picked YCbCr 4:4:4 for any HDMI sink that advertised it. Fixes: 0b0ff65d3ca1 ("drm/amd/display: Refactor stream validation") Suggested-by: Adolfo Rodrigues <adolfotregosa@gmail.com> Assisted-by: Claude Code:claude-fable-5-1 Signed-off-by: Adrian Betschart <adrian.betschart@cinemaone.ch> Reviewed-by: Fangzhi Zuo <jerry.zuo@amd.com> Tested-by: Adolfo Rodrigues <adolfotregosa@gmail.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> (cherry picked from commit 7de432bc753133764dc40d37f9388da56de251e7)
Diffstat (limited to 'drivers/phy/phy-can-transceiver.c')
-rw-r--r--drivers/phy/phy-can-transceiver.c258
1 files changed, 258 insertions, 0 deletions
diff --git a/drivers/phy/phy-can-transceiver.c b/drivers/phy/phy-can-transceiver.c
new file mode 100644
index 000000000..9aa306621
--- /dev/null
+++ b/drivers/phy/phy-can-transceiver.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * phy-can-transceiver.c - phy driver for CAN transceivers
+ *
+ * Copyright (C) 2021 Texas Instruments Incorporated - https://www.ti.com
+ *
+ */
+#include <linux/gpio/consumer.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/module.h>
+#include <linux/mux/consumer.h>
+
+struct can_transceiver_data {
+ u32 flags;
+#define CAN_TRANSCEIVER_STB_PRESENT BIT(0)
+#define CAN_TRANSCEIVER_EN_PRESENT BIT(1)
+#define CAN_TRANSCEIVER_DUAL_CH BIT(2)
+#define CAN_TRANSCEIVER_SILENT_PRESENT BIT(3)
+};
+
+struct can_transceiver_phy {
+ struct phy *generic_phy;
+ struct gpio_desc *silent_gpio;
+ struct gpio_desc *standby_gpio;
+ struct gpio_desc *enable_gpio;
+ struct can_transceiver_priv *priv;
+};
+
+struct can_transceiver_priv {
+ struct mux_state *mux_state;
+ int num_ch;
+ struct can_transceiver_phy can_transceiver_phy[] __counted_by(num_ch);
+};
+
+/* Power on function */
+static int can_transceiver_phy_power_on(struct phy *phy)
+{
+ struct can_transceiver_phy *can_transceiver_phy = phy_get_drvdata(phy);
+ struct can_transceiver_priv *priv = can_transceiver_phy->priv;
+ int ret;
+
+ if (priv->mux_state) {
+ ret = mux_state_select(priv->mux_state);
+ if (ret) {
+ dev_err(&phy->dev, "Failed to select CAN mux: %d\n", ret);
+ return ret;
+ }
+ }
+ gpiod_set_value_cansleep(can_transceiver_phy->silent_gpio, 0);
+ gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 0);
+ gpiod_set_value_cansleep(can_transceiver_phy->enable_gpio, 1);
+
+ return 0;
+}
+
+/* Power off function */
+static int can_transceiver_phy_power_off(struct phy *phy)
+{
+ struct can_transceiver_phy *can_transceiver_phy = phy_get_drvdata(phy);
+ struct can_transceiver_priv *priv = can_transceiver_phy->priv;
+
+ gpiod_set_value_cansleep(can_transceiver_phy->silent_gpio, 1);
+ gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 1);
+ gpiod_set_value_cansleep(can_transceiver_phy->enable_gpio, 0);
+ if (priv->mux_state)
+ mux_state_deselect(priv->mux_state);
+
+ return 0;
+}
+
+static const struct phy_ops can_transceiver_phy_ops = {
+ .power_on = can_transceiver_phy_power_on,
+ .power_off = can_transceiver_phy_power_off,
+ .owner = THIS_MODULE,
+};
+
+static const struct can_transceiver_data tcan1042_drvdata = {
+ .flags = CAN_TRANSCEIVER_STB_PRESENT,
+};
+
+static const struct can_transceiver_data tcan1043_drvdata = {
+ .flags = CAN_TRANSCEIVER_STB_PRESENT | CAN_TRANSCEIVER_EN_PRESENT,
+};
+
+static const struct can_transceiver_data tja1048_drvdata = {
+ .flags = CAN_TRANSCEIVER_STB_PRESENT | CAN_TRANSCEIVER_DUAL_CH,
+};
+
+static const struct can_transceiver_data tja1051_drvdata = {
+ .flags = CAN_TRANSCEIVER_SILENT_PRESENT | CAN_TRANSCEIVER_EN_PRESENT,
+};
+
+static const struct can_transceiver_data tja1057_drvdata = {
+ .flags = CAN_TRANSCEIVER_SILENT_PRESENT,
+};
+
+static struct phy *can_transceiver_phy_xlate(struct device *dev,
+ const struct of_phandle_args *args)
+{
+ struct can_transceiver_priv *priv = dev_get_drvdata(dev);
+ u32 idx;
+
+ if (priv->num_ch == 1)
+ return priv->can_transceiver_phy[0].generic_phy;
+
+ if (args->args_count != 1)
+ return ERR_PTR(-EINVAL);
+
+ idx = args->args[0];
+ if (idx >= priv->num_ch)
+ return ERR_PTR(-EINVAL);
+
+ return priv->can_transceiver_phy[idx].generic_phy;
+}
+
+static int can_transceiver_phy_probe(struct platform_device *pdev)
+{
+ struct phy_provider *phy_provider;
+ struct device *dev = &pdev->dev;
+ struct can_transceiver_phy *can_transceiver_phy;
+ struct can_transceiver_priv *priv;
+ const struct can_transceiver_data *drvdata;
+ struct phy *phy;
+ struct gpio_desc *silent_gpio;
+ struct gpio_desc *standby_gpio;
+ struct gpio_desc *enable_gpio;
+ struct mux_state *mux_state;
+ const char *propname;
+ int err, i, num_ch;
+ u32 max_bitrate;
+
+ drvdata = device_get_match_data(dev);
+ if (!drvdata)
+ return -ENODEV;
+
+ if (drvdata->flags & CAN_TRANSCEIVER_DUAL_CH)
+ num_ch = 2;
+ else
+ num_ch = 1;
+
+ priv = devm_kzalloc(dev, struct_size(priv, can_transceiver_phy, num_ch), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->num_ch = num_ch;
+ platform_set_drvdata(pdev, priv);
+
+ mux_state = devm_mux_state_get_optional(dev, NULL);
+ if (IS_ERR(mux_state))
+ return PTR_ERR(mux_state);
+
+ priv->mux_state = mux_state;
+
+ propname = "max-bitrate";
+ if (device_property_present(dev, propname)) {
+ err = device_property_read_u32(dev, propname, &max_bitrate);
+ if (err)
+ return dev_err_probe(dev, err, "failed to parse %s\n", propname);
+
+ if (max_bitrate == 0)
+ dev_warn(dev, "Invalid value for transceiver max bitrate. Ignoring bitrate limit\n");
+ } else {
+ max_bitrate = 0;
+ }
+
+ for (i = 0; i < num_ch; i++) {
+ can_transceiver_phy = &priv->can_transceiver_phy[i];
+ can_transceiver_phy->priv = priv;
+
+ phy = devm_phy_create(dev, NULL, &can_transceiver_phy_ops);
+ if (IS_ERR(phy)) {
+ dev_err(dev, "failed to create can transceiver phy\n");
+ return PTR_ERR(phy);
+ }
+
+ phy->attrs.max_link_rate = max_bitrate;
+
+ can_transceiver_phy->generic_phy = phy;
+ can_transceiver_phy->priv = priv;
+
+ if (drvdata->flags & CAN_TRANSCEIVER_STB_PRESENT) {
+ standby_gpio = devm_gpiod_get_index_optional(dev, "standby", i,
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(standby_gpio))
+ return PTR_ERR(standby_gpio);
+ can_transceiver_phy->standby_gpio = standby_gpio;
+ }
+
+ if (drvdata->flags & CAN_TRANSCEIVER_EN_PRESENT) {
+ enable_gpio = devm_gpiod_get_index_optional(dev, "enable", i,
+ GPIOD_OUT_LOW);
+ if (IS_ERR(enable_gpio))
+ return PTR_ERR(enable_gpio);
+ can_transceiver_phy->enable_gpio = enable_gpio;
+ }
+
+ if (drvdata->flags & CAN_TRANSCEIVER_SILENT_PRESENT) {
+ silent_gpio = devm_gpiod_get_index_optional(dev, "silent", i,
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(silent_gpio))
+ return PTR_ERR(silent_gpio);
+ can_transceiver_phy->silent_gpio = silent_gpio;
+ }
+
+ phy_set_drvdata(can_transceiver_phy->generic_phy, can_transceiver_phy);
+
+ }
+
+ phy_provider = devm_of_phy_provider_register(dev, can_transceiver_phy_xlate);
+
+ return PTR_ERR_OR_ZERO(phy_provider);
+}
+
+static const struct of_device_id can_transceiver_phy_ids[] = {
+ {
+ .compatible = "ti,tcan1042",
+ .data = &tcan1042_drvdata
+ },
+ {
+ .compatible = "ti,tcan1043",
+ .data = &tcan1043_drvdata
+ },
+ {
+ .compatible = "nxp,tja1048",
+ .data = &tja1048_drvdata
+ },
+ {
+ .compatible = "nxp,tja1051",
+ .data = &tja1051_drvdata
+ },
+ {
+ .compatible = "nxp,tja1057",
+ .data = &tja1057_drvdata
+ },
+ {
+ .compatible = "nxp,tjr1443",
+ .data = &tcan1043_drvdata
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(of, can_transceiver_phy_ids);
+
+static struct platform_driver can_transceiver_phy_driver = {
+ .probe = can_transceiver_phy_probe,
+ .driver = {
+ .name = "can-transceiver-phy",
+ .of_match_table = can_transceiver_phy_ids,
+ },
+};
+
+module_platform_driver(can_transceiver_phy_driver);
+
+MODULE_AUTHOR("Faiz Abbas <faiz_abbas@ti.com>");
+MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
+MODULE_DESCRIPTION("CAN TRANSCEIVER PHY driver");
+MODULE_LICENSE("GPL v2");