[PATCH 0/2] Add driver for NXP PTN36502 Type-C redriver

[PATCH 0/2] Add driver for NXP PTN36502 Type-C redriver

[Luca Weiss]

The NXP PTN36502 is used in the Fairphone 5 smartphone, add a driver for
it so we can soon enable DisplayPort over USB-C on this phone.

Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
---
Luca Weiss (2):
      dt-bindings: usb: add NXP PTN36502 Type-C redriver bindings
      usb: typec: add support for PTN36502 redriver

 .../devicetree/bindings/usb/nxp,ptn36502.yaml      |  94 +++++
 drivers/usb/typec/mux/Kconfig                      |  10 +
 drivers/usb/typec/mux/Makefile                     |   1 +
 drivers/usb/typec/mux/ptn36502.c                   | 421 +++++++++++++++++++++
 4 files changed, 526 insertions(+)
---
base-commit: e3b18f7200f45d66f7141136c25554ac1e82009b
change-id: 20231013-ptn36502-5a87e507d36c

Best regards,
-- 
Luca Weiss <luca.weiss@fairphone.com>

[PATCH 1/2] dt-bindings: usb: add NXP PTN36502 Type-C redriver bindings

[Luca Weiss]

Document bindings for this Type-C USB 3.1 Gen 1 and DisplayPort v1.2
combo redriver.

The PTN36502 can also run in GPIO mode where it is configured
differently, without any I2C connection, but this is not supported yet.

Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
---
 .../devicetree/bindings/usb/nxp,ptn36502.yaml      | 94 ++++++++++++++++++++++
 1 file changed, 94 insertions(+)

diff --git a/Documentation/devicetree/bindings/usb/nxp,ptn36502.yaml b/Documentation/devicetree/bindings/usb/nxp,ptn36502.yaml
new file mode 100644
index 000000000000..eee548ac1abe
--- /dev/null
+++ b/Documentation/devicetree/bindings/usb/nxp,ptn36502.yaml
@@ -0,0 +1,94 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/usb/nxp,ptn36502.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NXP PTN36502 Type-C USB 3.1 Gen 1 and DisplayPort v1.2 combo redriver
+
+maintainers:
+  - Luca Weiss <luca.weiss@fairphone.com>
+
+properties:
+  compatible:
+    enum:
+      - nxp,ptn36502
+
+  reg:
+    maxItems: 1
+
+  vdd18-supply:
+    description: Power supply for VDD18 pin
+
+  retimer-switch:
+    description: Flag the port as possible handle of SuperSpeed signals retiming
+    type: boolean
+
+  orientation-switch:
+    description: Flag the port as possible handler of orientation switching
+    type: boolean
+
+  ports:
+    $ref: /schemas/graph.yaml#/properties/ports
+    properties:
+      port@0:
+        $ref: /schemas/graph.yaml#/properties/port
+        description: Super Speed (SS) Output endpoint to the Type-C connector
+
+      port@1:
+        $ref: /schemas/graph.yaml#/properties/port
+        description: Super Speed (SS) Input endpoint from the Super-Speed PHY
+
+      port@2:
+        $ref: /schemas/graph.yaml#/properties/port
+        description:
+          Sideband Use (SBU) AUX lines endpoint to the Type-C connector for the purpose of
+          handling altmode muxing and orientation switching.
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        typec-mux@1a {
+            compatible = "nxp,ptn36502";
+            reg = <0x1a>;
+
+            vdd18-supply = <&usb_redrive_1v8>;
+
+            retimer-switch;
+            orientation-switch;
+
+            ports {
+                #address-cells = <1>;
+                #size-cells = <0>;
+
+                port@0 {
+                    reg = <0>;
+                    usb_con_ss: endpoint {
+                        remote-endpoint = <&typec_con_ss>;
+                    };
+                };
+                port@1 {
+                    reg = <1>;
+                    phy_con_ss: endpoint {
+                        remote-endpoint = <&usb_phy_ss>;
+                    };
+                };
+                port@2 {
+                    reg = <2>;
+                    usb_con_sbu: endpoint {
+                        remote-endpoint = <&typec_dp_aux>;
+                    };
+                };
+            };
+        };
+    };
+...

-- 
2.42.0

[PATCH 2/2] usb: typec: add support for PTN36502 redriver

[Luca Weiss]

Add a driver for the NXP PTN36502 Type-C USB 3.1 Gen 1 and DisplayPort
v1.2 combo redriver.

Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
---
 drivers/usb/typec/mux/Kconfig    |  10 +
 drivers/usb/typec/mux/Makefile   |   1 +
 drivers/usb/typec/mux/ptn36502.c | 421 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 432 insertions(+)

diff --git a/drivers/usb/typec/mux/Kconfig b/drivers/usb/typec/mux/Kconfig
index 65da61150ba7..816b9bd08355 100644
--- a/drivers/usb/typec/mux/Kconfig
+++ b/drivers/usb/typec/mux/Kconfig
@@ -46,4 +46,14 @@ config TYPEC_MUX_NB7VPQ904M
 	  Say Y or M if your system has a On Semiconductor NB7VPQ904M Type-C
 	  redriver chip found on some devices with a Type-C port.
 
+config TYPEC_MUX_PTN36502
+	tristate "NXP PTN36502 Type-C redriver driver"
+	depends on I2C
+	depends on DRM || DRM=n
+	select DRM_PANEL_BRIDGE if DRM
+	select REGMAP_I2C
+	help
+	  Say Y or M if your system has a NXP PTN36502 Type-C redriver chip
+	  found on some devices with a Type-C port.
+
 endmenu
diff --git a/drivers/usb/typec/mux/Makefile b/drivers/usb/typec/mux/Makefile
index 76196096ef41..9d6a5557b0bd 100644
--- a/drivers/usb/typec/mux/Makefile
+++ b/drivers/usb/typec/mux/Makefile
@@ -5,3 +5,4 @@ obj-$(CONFIG_TYPEC_MUX_GPIO_SBU)	+= gpio-sbu-mux.o
 obj-$(CONFIG_TYPEC_MUX_PI3USB30532)	+= pi3usb30532.o
 obj-$(CONFIG_TYPEC_MUX_INTEL_PMC)	+= intel_pmc_mux.o
 obj-$(CONFIG_TYPEC_MUX_NB7VPQ904M)	+= nb7vpq904m.o
+obj-$(CONFIG_TYPEC_MUX_PTN36502)	+= ptn36502.o
diff --git a/drivers/usb/typec/mux/ptn36502.c b/drivers/usb/typec/mux/ptn36502.c
new file mode 100644
index 000000000000..91684a856f3a
--- /dev/null
+++ b/drivers/usb/typec/mux/ptn36502.c
@@ -0,0 +1,421 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * NXP PTN36502 Type-C driver
+ *
+ * Copyright (C) 2023 Luca Weiss <luca.weiss@fairphone.com>
+ *
+ * Based on NB7VPQ904M driver:
+ * Copyright (C) 2023 Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
+ */
+
+#include <drm/drm_bridge.h>
+#include <linux/bitfield.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_graph.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/usb/typec_dp.h>
+#include <linux/usb/typec_mux.h>
+#include <linux/usb/typec_retimer.h>
+
+#define PTN36502_CHIP_ID_REG				0x00
+#define PTN36502_CHIP_ID				0x02
+
+#define PTN36502_CHIP_REVISION_REG			0x01
+#define PTN36502_CHIP_REVISION_BASE(val)		FIELD_GET(GENMASK(7, 4), (val))
+#define PTN36502_CHIP_REVISION_METAL(val)		FIELD_GET(GENMASK(3, 0), (val))
+
+#define PTN36502_DP_LINK_CTRL_REG			0x06
+#define PTN36502_DP_LINK_CTRL_LANES_2			(2 << 2)
+#define PTN36502_DP_LINK_CTRL_LANES_4			(3 << 2)
+#define PTN36502_DP_LINK_CTRL_LINK_RATE_5_4GBPS		(2 << 0)
+
+/* Registers for lane 0 (0x07) to lane 3 (0x0a) have the same layout */
+#define PTN36502_DP_LANE_CTRL_REG(n)			(0x07 + (n))
+#define PTN36502_DP_LANE_CTRL_RX_GAIN_3DB		(2<<4)
+#define PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD		(2<<2)
+#define PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_3_5DB	(1<<0)
+
+#define PTN36502_MODE_CTRL1_REG				0x0b
+#define PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE		(1<<5)
+#define PTN36502_MODE_CTRL1_AUX_CROSSBAR_SW_ON		(1<<3)
+#define PTN36502_MODE_CTRL1_MODE_OFF			(0<<0)
+#define PTN36502_MODE_CTRL1_MODE_USB_ONLY		(1<<0)
+#define PTN36502_MODE_CTRL1_MODE_USB_DP			(2<<0)
+#define PTN36502_MODE_CTRL1_MODE_DP			(3<<0)
+
+#define PTN36502_DEVICE_CTRL_REG			0x0d
+#define PTN36502_DEVICE_CTRL_AUX_MONITORING_EN		(1<<7)
+
+struct ptn36502 {
+	struct i2c_client *client;
+	struct regulator *vdd18_supply;
+	struct regmap *regmap;
+	struct typec_switch_dev *sw;
+	struct typec_retimer *retimer;
+
+	struct typec_switch *typec_switch;
+
+	struct drm_bridge bridge;
+
+	struct mutex lock; /* protect non-concurrent retimer & switch */
+
+	enum typec_orientation orientation;
+	unsigned long mode;
+	unsigned int svid;
+};
+
+static int ptn36502_set(struct ptn36502 *ptn)
+{
+	bool reverse = (ptn->orientation == TYPEC_ORIENTATION_REVERSE);
+	unsigned int ctrl1_val = 0;
+	unsigned int lane_ctrl_val = 0;
+	unsigned int link_ctrl_val = 0;
+
+	switch (ptn->mode) {
+	case TYPEC_STATE_SAFE:
+		/* Deep power saving state */
+		regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG,
+			     PTN36502_MODE_CTRL1_MODE_OFF);
+		return 0;
+
+	case TYPEC_STATE_USB:
+		/*
+		 * Normal Orientation (CC1)
+		 * A -> USB RX
+		 * B -> USB TX
+		 * C -> X
+		 * D -> X
+		 * Flipped Orientation (CC2)
+		 * A -> X
+		 * B -> X
+		 * C -> USB TX
+		 * D -> USB RX
+		 */
+
+		/* USB 3.1 Gen 1 only */
+		ctrl1_val = PTN36502_MODE_CTRL1_MODE_USB_ONLY;
+		if (reverse)
+			ctrl1_val |= PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE;
+
+		regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG, ctrl1_val);
+		return 0;
+
+	default:
+		if (ptn->svid != USB_TYPEC_DP_SID)
+			return -EINVAL;
+
+		break;
+	}
+
+	/* DP Altmode Setup */
+
+	switch (ptn->mode) {
+	case TYPEC_DP_STATE_C:
+	case TYPEC_DP_STATE_E:
+		/*
+		 * Normal Orientation (CC1)
+		 * A -> DP3
+		 * B -> DP2
+		 * C -> DP1
+		 * D -> DP0
+		 * Flipped Orientation (CC2)
+		 * A -> DP0
+		 * B -> DP1
+		 * C -> DP2
+		 * D -> DP3
+		 */
+
+		/* 4-lane DP */
+		ctrl1_val |= PTN36502_MODE_CTRL1_MODE_DP;
+		link_ctrl_val |= PTN36502_DP_LINK_CTRL_LANES_4;
+		break;
+
+	case TYPEC_DP_STATE_D:
+	case TYPEC_DP_STATE_F: /* State F is deprecated */
+		/*
+		 * Normal Orientation (CC1)
+		 * A -> USB RX
+		 * B -> USB TX
+		 * C -> DP1
+		 * D -> DP0
+		 * Flipped Orientation (CC2)
+		 * A -> DP0
+		 * B -> DP1
+		 * C -> USB TX
+		 * D -> USB RX
+		 */
+
+		/* USB 3.1 Gen 1 and 2-lane DP */
+		ctrl1_val |= PTN36502_MODE_CTRL1_MODE_USB_DP;
+		link_ctrl_val |= PTN36502_DP_LINK_CTRL_LANES_2;
+		break;
+
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	/* Enable AUX monitoring */
+	regmap_write(ptn->regmap, PTN36502_DEVICE_CTRL_REG,
+		     PTN36502_DEVICE_CTRL_AUX_MONITORING_EN);
+
+	/* Enable AUX switch path */
+	ctrl1_val |= PTN36502_MODE_CTRL1_AUX_CROSSBAR_SW_ON;
+	if (reverse)
+		ctrl1_val |= PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE;
+	regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG, ctrl1_val);
+
+	/* DP Link rate: 5.4 Gbps (HBR2) */
+	link_ctrl_val |= PTN36502_DP_LINK_CTRL_LINK_RATE_5_4GBPS;
+	regmap_write(ptn->regmap, PTN36502_DP_LINK_CTRL_REG, link_ctrl_val);
+
+	/*
+	 * For all lanes:
+	 * - Rx equivalization gain: 3 dB
+	 * - TX output swing control: 800 mVppd
+	 * - Pre-emphasis control: 3.5 dB
+	 */
+	lane_ctrl_val = PTN36502_DP_LANE_CTRL_RX_GAIN_3DB |
+			PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD |
+			PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_3_5DB;
+	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(0), lane_ctrl_val);
+	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(1), lane_ctrl_val);
+	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(2), lane_ctrl_val);
+	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(3), lane_ctrl_val);
+
+	return 0;
+}
+
+static int ptn36502_sw_set(struct typec_switch_dev *sw, enum typec_orientation orientation)
+{
+	struct ptn36502 *ptn = typec_switch_get_drvdata(sw);
+	int ret;
+
+	ret = typec_switch_set(ptn->typec_switch, orientation);
+	if (ret)
+		return ret;
+
+	mutex_lock(&ptn->lock);
+
+	if (ptn->orientation != orientation) {
+		ptn->orientation = orientation;
+
+		ret = ptn36502_set(ptn);
+	}
+
+	mutex_unlock(&ptn->lock);
+
+	return ret;
+}
+
+static int ptn36502_retimer_set(struct typec_retimer *retimer, struct typec_retimer_state *state)
+{
+	struct ptn36502 *ptn = typec_retimer_get_drvdata(retimer);
+	int ret = 0;
+
+	mutex_lock(&ptn->lock);
+
+	if (ptn->mode != state->mode) {
+		ptn->mode = state->mode;
+
+		if (state->alt)
+			ptn->svid = state->alt->svid;
+		else
+			ptn->svid = 0; // No SVID
+
+		ret = ptn36502_set(ptn);
+	}
+
+	mutex_unlock(&ptn->lock);
+
+	return ret;
+}
+
+static int ptn36502_detect(struct ptn36502 *ptn)
+{
+	struct device *dev = &ptn->client->dev;
+	unsigned int reg_val;
+	int ret;
+
+	ret = regmap_read(ptn->regmap, PTN36502_CHIP_ID_REG,
+			  &reg_val);
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "Failed to read chip ID\n");
+
+	if (reg_val != PTN36502_CHIP_ID)
+		return dev_err_probe(dev, -ENODEV, "Unexpected chip ID: %x\n", reg_val);
+
+	ret = regmap_read(ptn->regmap, PTN36502_CHIP_REVISION_REG,
+			  &reg_val);
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "Failed to read chip revision\n");
+
+	dev_dbg(dev, "Chip revision: base layer version %lx, metal layer version %lx\n",
+		PTN36502_CHIP_REVISION_BASE(reg_val),
+		PTN36502_CHIP_REVISION_METAL(reg_val));
+
+	return 0;
+}
+
+#if IS_ENABLED(CONFIG_OF) && IS_ENABLED(CONFIG_DRM_PANEL_BRIDGE)
+static int ptn36502_bridge_attach(struct drm_bridge *bridge,
+				    enum drm_bridge_attach_flags flags)
+{
+	struct ptn36502 *ptn = container_of(bridge, struct ptn36502, bridge);
+	struct drm_bridge *next_bridge;
+
+	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
+		return -EINVAL;
+
+	next_bridge = devm_drm_of_get_bridge(&ptn->client->dev, ptn->client->dev.of_node, 0, 0);
+	if (IS_ERR(next_bridge)) {
+		dev_err(&ptn->client->dev, "failed to acquire drm_bridge: %pe\n", next_bridge);
+		return PTR_ERR(next_bridge);
+	}
+
+	return drm_bridge_attach(bridge->encoder, next_bridge, bridge,
+				 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
+}
+
+static const struct drm_bridge_funcs ptn36502_bridge_funcs = {
+	.attach	= ptn36502_bridge_attach,
+};
+
+static int ptn36502_register_bridge(struct ptn36502 *ptn)
+{
+	ptn->bridge.funcs = &ptn36502_bridge_funcs;
+	ptn->bridge.of_node = ptn->client->dev.of_node;
+
+	return devm_drm_bridge_add(&ptn->client->dev, &ptn->bridge);
+}
+#else
+static int ptn36502_register_bridge(struct ptn36502 *ptn)
+{
+	return 0;
+}
+#endif
+
+static const struct regmap_config ptn36502_regmap = {
+	.max_register = 0x0d,
+	.reg_bits = 8,
+	.val_bits = 8,
+};
+
+static int ptn36502_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct typec_switch_desc sw_desc = { };
+	struct typec_retimer_desc retimer_desc = { };
+	struct ptn36502 *ptn;
+	int ret;
+
+	ptn = devm_kzalloc(dev, sizeof(*ptn), GFP_KERNEL);
+	if (!ptn)
+		return -ENOMEM;
+
+	ptn->client = client;
+
+	ptn->regmap = devm_regmap_init_i2c(client, &ptn36502_regmap);
+	if (IS_ERR(ptn->regmap)) {
+		dev_err(&client->dev, "Failed to allocate register map\n");
+		return PTR_ERR(ptn->regmap);
+	}
+
+	ptn->mode = TYPEC_STATE_SAFE;
+	ptn->orientation = TYPEC_ORIENTATION_NONE;
+
+	mutex_init(&ptn->lock);
+
+	ptn->vdd18_supply = devm_regulator_get_optional(dev, "vdd18");
+	if (IS_ERR(ptn->vdd18_supply))
+		return PTR_ERR(ptn->vdd18_supply);
+
+	ptn->typec_switch = fwnode_typec_switch_get(dev->fwnode);
+	if (IS_ERR(ptn->typec_switch))
+		return dev_err_probe(dev, PTR_ERR(ptn->typec_switch),
+				     "Failed to acquire orientation-switch\n");
+
+	ret = regulator_enable(ptn->vdd18_supply);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to enable vdd18\n");
+
+	ret = ptn36502_detect(ptn);
+	if (ret)
+		goto err_disable_regulator;
+
+	ret = ptn36502_register_bridge(ptn);
+	if (ret)
+		goto err_disable_regulator;
+
+	sw_desc.drvdata = ptn;
+	sw_desc.fwnode = dev->fwnode;
+	sw_desc.set = ptn36502_sw_set;
+
+	ptn->sw = typec_switch_register(dev, &sw_desc);
+	if (IS_ERR(ptn->sw)) {
+		ret = dev_err_probe(dev, PTR_ERR(ptn->sw),
+				    "Failed to register typec switch\n");
+		goto err_disable_regulator;
+	}
+
+	retimer_desc.drvdata = ptn;
+	retimer_desc.fwnode = dev->fwnode;
+	retimer_desc.set = ptn36502_retimer_set;
+
+	ptn->retimer = typec_retimer_register(dev, &retimer_desc);
+	if (IS_ERR(ptn->retimer)) {
+		ret = dev_err_probe(dev, PTR_ERR(ptn->retimer),
+				    "Failed to register typec retimer\n");
+		goto err_switch_unregister;
+	}
+
+	return 0;
+
+err_switch_unregister:
+	typec_switch_unregister(ptn->sw);
+
+err_disable_regulator:
+	regulator_disable(ptn->vdd18_supply);
+
+	return ret;
+}
+
+static void ptn36502_remove(struct i2c_client *client)
+{
+	struct ptn36502 *ptn = i2c_get_clientdata(client);
+
+	typec_retimer_unregister(ptn->retimer);
+	typec_switch_unregister(ptn->sw);
+
+	regulator_disable(ptn->vdd18_supply);
+}
+
+static const struct i2c_device_id ptn36502_table[] = {
+	{ "ptn36502" },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, ptn36502_table);
+
+static const struct of_device_id ptn36502_of_table[] = {
+	{ .compatible = "nxp,ptn36502" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ptn36502_of_table);
+
+static struct i2c_driver ptn36502_driver = {
+	.driver = {
+		.name = "ptn36502",
+		.of_match_table = ptn36502_of_table,
+	},
+	.probe		= ptn36502_probe,
+	.remove		= ptn36502_remove,
+	.id_table	= ptn36502_table,
+};
+module_i2c_driver(ptn36502_driver);
+
+MODULE_AUTHOR("Luca Weiss <luca.weiss@fairphone.com>");
+MODULE_DESCRIPTION("NXP PTN36502 Type-C driver");
+MODULE_LICENSE("GPL");

-- 
2.42.0

Re: [PATCH 1/2] dt-bindings: usb: add NXP PTN36502 Type-C redriver bindings

[Krzysztof Kozlowski]

On 13/10/2023 16:24, Luca Weiss wrote:
> Document bindings for this Type-C USB 3.1 Gen 1 and DisplayPort v1.2
> combo redriver.
> 
> The PTN36502 can also run in GPIO mode where it is configured
> differently, without any I2C connection, but this is not supported yet.
> 
> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof

Re: [PATCH 2/2] usb: typec: add support for PTN36502 redriver

[Heikki Krogerus]

Hi,

On Fri, Oct 13, 2023 at 04:24:48PM +0200, Luca Weiss wrote:
> Add a driver for the NXP PTN36502 Type-C USB 3.1 Gen 1 and DisplayPort
> v1.2 combo redriver.
> 
> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>

Looks OK to me, but couple of nitpicks below. With those fixed:

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>

> ---
>  drivers/usb/typec/mux/Kconfig    |  10 +
>  drivers/usb/typec/mux/Makefile   |   1 +
>  drivers/usb/typec/mux/ptn36502.c | 421 +++++++++++++++++++++++++++++++++++++++
>  3 files changed, 432 insertions(+)
> 
> diff --git a/drivers/usb/typec/mux/Kconfig b/drivers/usb/typec/mux/Kconfig
> index 65da61150ba7..816b9bd08355 100644
> --- a/drivers/usb/typec/mux/Kconfig
> +++ b/drivers/usb/typec/mux/Kconfig
> @@ -46,4 +46,14 @@ config TYPEC_MUX_NB7VPQ904M
>  	  Say Y or M if your system has a On Semiconductor NB7VPQ904M Type-C
>  	  redriver chip found on some devices with a Type-C port.
>  
> +config TYPEC_MUX_PTN36502
> +	tristate "NXP PTN36502 Type-C redriver driver"
> +	depends on I2C
> +	depends on DRM || DRM=n
> +	select DRM_PANEL_BRIDGE if DRM
> +	select REGMAP_I2C
> +	help
> +	  Say Y or M if your system has a NXP PTN36502 Type-C redriver chip
> +	  found on some devices with a Type-C port.
> +
>  endmenu
> diff --git a/drivers/usb/typec/mux/Makefile b/drivers/usb/typec/mux/Makefile
> index 76196096ef41..9d6a5557b0bd 100644
> --- a/drivers/usb/typec/mux/Makefile
> +++ b/drivers/usb/typec/mux/Makefile
> @@ -5,3 +5,4 @@ obj-$(CONFIG_TYPEC_MUX_GPIO_SBU)	+= gpio-sbu-mux.o
>  obj-$(CONFIG_TYPEC_MUX_PI3USB30532)	+= pi3usb30532.o
>  obj-$(CONFIG_TYPEC_MUX_INTEL_PMC)	+= intel_pmc_mux.o
>  obj-$(CONFIG_TYPEC_MUX_NB7VPQ904M)	+= nb7vpq904m.o
> +obj-$(CONFIG_TYPEC_MUX_PTN36502)	+= ptn36502.o
> diff --git a/drivers/usb/typec/mux/ptn36502.c b/drivers/usb/typec/mux/ptn36502.c
> new file mode 100644
> index 000000000000..91684a856f3a
> --- /dev/null
> +++ b/drivers/usb/typec/mux/ptn36502.c
> @@ -0,0 +1,421 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * NXP PTN36502 Type-C driver
> + *
> + * Copyright (C) 2023 Luca Weiss <luca.weiss@fairphone.com>
> + *
> + * Based on NB7VPQ904M driver:
> + * Copyright (C) 2023 Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> + */
> +
> +#include <drm/drm_bridge.h>
> +#include <linux/bitfield.h>
> +#include <linux/i2c.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/of_graph.h>
> +#include <linux/regmap.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/usb/typec_dp.h>
> +#include <linux/usb/typec_mux.h>
> +#include <linux/usb/typec_retimer.h>
> +
> +#define PTN36502_CHIP_ID_REG				0x00
> +#define PTN36502_CHIP_ID				0x02
> +
> +#define PTN36502_CHIP_REVISION_REG			0x01
> +#define PTN36502_CHIP_REVISION_BASE(val)		FIELD_GET(GENMASK(7, 4), (val))
> +#define PTN36502_CHIP_REVISION_METAL(val)		FIELD_GET(GENMASK(3, 0), (val))
> +
> +#define PTN36502_DP_LINK_CTRL_REG			0x06
> +#define PTN36502_DP_LINK_CTRL_LANES_2			(2 << 2)
> +#define PTN36502_DP_LINK_CTRL_LANES_4			(3 << 2)
> +#define PTN36502_DP_LINK_CTRL_LINK_RATE_5_4GBPS		(2 << 0)
> +
> +/* Registers for lane 0 (0x07) to lane 3 (0x0a) have the same layout */
> +#define PTN36502_DP_LANE_CTRL_REG(n)			(0x07 + (n))
> +#define PTN36502_DP_LANE_CTRL_RX_GAIN_3DB		(2<<4)
> +#define PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD		(2<<2)
> +#define PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_3_5DB	(1<<0)
> +
> +#define PTN36502_MODE_CTRL1_REG				0x0b
> +#define PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE		(1<<5)
> +#define PTN36502_MODE_CTRL1_AUX_CROSSBAR_SW_ON		(1<<3)
> +#define PTN36502_MODE_CTRL1_MODE_OFF			(0<<0)
> +#define PTN36502_MODE_CTRL1_MODE_USB_ONLY		(1<<0)
> +#define PTN36502_MODE_CTRL1_MODE_USB_DP			(2<<0)
> +#define PTN36502_MODE_CTRL1_MODE_DP			(3<<0)
> +
> +#define PTN36502_DEVICE_CTRL_REG			0x0d
> +#define PTN36502_DEVICE_CTRL_AUX_MONITORING_EN		(1<<7)

You have couple of different styles here. Please try to always use
BIT() and GENMASK() macros when possible. At the very least put spaces
around << and >>.

> +struct ptn36502 {
> +	struct i2c_client *client;
> +	struct regulator *vdd18_supply;
> +	struct regmap *regmap;
> +	struct typec_switch_dev *sw;
> +	struct typec_retimer *retimer;
> +
> +	struct typec_switch *typec_switch;
> +
> +	struct drm_bridge bridge;
> +
> +	struct mutex lock; /* protect non-concurrent retimer & switch */
> +
> +	enum typec_orientation orientation;
> +	unsigned long mode;
> +	unsigned int svid;
> +};
> +
> +static int ptn36502_set(struct ptn36502 *ptn)
> +{
> +	bool reverse = (ptn->orientation == TYPEC_ORIENTATION_REVERSE);
> +	unsigned int ctrl1_val = 0;
> +	unsigned int lane_ctrl_val = 0;
> +	unsigned int link_ctrl_val = 0;
> +
> +	switch (ptn->mode) {
> +	case TYPEC_STATE_SAFE:
> +		/* Deep power saving state */
> +		regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG,
> +			     PTN36502_MODE_CTRL1_MODE_OFF);
> +		return 0;
> +
> +	case TYPEC_STATE_USB:
> +		/*
> +		 * Normal Orientation (CC1)
> +		 * A -> USB RX
> +		 * B -> USB TX
> +		 * C -> X
> +		 * D -> X
> +		 * Flipped Orientation (CC2)
> +		 * A -> X
> +		 * B -> X
> +		 * C -> USB TX
> +		 * D -> USB RX
> +		 */
> +
> +		/* USB 3.1 Gen 1 only */
> +		ctrl1_val = PTN36502_MODE_CTRL1_MODE_USB_ONLY;
> +		if (reverse)
> +			ctrl1_val |= PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE;
> +
> +		regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG, ctrl1_val);
> +		return 0;
> +
> +	default:
> +		if (ptn->svid != USB_TYPEC_DP_SID)
> +			return -EINVAL;
> +
> +		break;
> +	}
> +
> +	/* DP Altmode Setup */
> +
> +	switch (ptn->mode) {
> +	case TYPEC_DP_STATE_C:
> +	case TYPEC_DP_STATE_E:
> +		/*
> +		 * Normal Orientation (CC1)
> +		 * A -> DP3
> +		 * B -> DP2
> +		 * C -> DP1
> +		 * D -> DP0
> +		 * Flipped Orientation (CC2)
> +		 * A -> DP0
> +		 * B -> DP1
> +		 * C -> DP2
> +		 * D -> DP3
> +		 */
> +
> +		/* 4-lane DP */
> +		ctrl1_val |= PTN36502_MODE_CTRL1_MODE_DP;
> +		link_ctrl_val |= PTN36502_DP_LINK_CTRL_LANES_4;
> +		break;
> +
> +	case TYPEC_DP_STATE_D:
> +	case TYPEC_DP_STATE_F: /* State F is deprecated */
> +		/*
> +		 * Normal Orientation (CC1)
> +		 * A -> USB RX
> +		 * B -> USB TX
> +		 * C -> DP1
> +		 * D -> DP0
> +		 * Flipped Orientation (CC2)
> +		 * A -> DP0
> +		 * B -> DP1
> +		 * C -> USB TX
> +		 * D -> USB RX
> +		 */
> +
> +		/* USB 3.1 Gen 1 and 2-lane DP */
> +		ctrl1_val |= PTN36502_MODE_CTRL1_MODE_USB_DP;
> +		link_ctrl_val |= PTN36502_DP_LINK_CTRL_LANES_2;
> +		break;
> +
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +
> +	/* Enable AUX monitoring */
> +	regmap_write(ptn->regmap, PTN36502_DEVICE_CTRL_REG,
> +		     PTN36502_DEVICE_CTRL_AUX_MONITORING_EN);
> +
> +	/* Enable AUX switch path */
> +	ctrl1_val |= PTN36502_MODE_CTRL1_AUX_CROSSBAR_SW_ON;
> +	if (reverse)
> +		ctrl1_val |= PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE;
> +	regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG, ctrl1_val);
> +
> +	/* DP Link rate: 5.4 Gbps (HBR2) */
> +	link_ctrl_val |= PTN36502_DP_LINK_CTRL_LINK_RATE_5_4GBPS;
> +	regmap_write(ptn->regmap, PTN36502_DP_LINK_CTRL_REG, link_ctrl_val);
> +
> +	/*
> +	 * For all lanes:
> +	 * - Rx equivalization gain: 3 dB
> +	 * - TX output swing control: 800 mVppd
> +	 * - Pre-emphasis control: 3.5 dB
> +	 */
> +	lane_ctrl_val = PTN36502_DP_LANE_CTRL_RX_GAIN_3DB |
> +			PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD |
> +			PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_3_5DB;
> +	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(0), lane_ctrl_val);
> +	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(1), lane_ctrl_val);
> +	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(2), lane_ctrl_val);
> +	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(3), lane_ctrl_val);
> +
> +	return 0;
> +}
> +
> +static int ptn36502_sw_set(struct typec_switch_dev *sw, enum typec_orientation orientation)
> +{
> +	struct ptn36502 *ptn = typec_switch_get_drvdata(sw);
> +	int ret;
> +
> +	ret = typec_switch_set(ptn->typec_switch, orientation);
> +	if (ret)
> +		return ret;
> +
> +	mutex_lock(&ptn->lock);
> +
> +	if (ptn->orientation != orientation) {
> +		ptn->orientation = orientation;
> +
> +		ret = ptn36502_set(ptn);
> +	}
> +
> +	mutex_unlock(&ptn->lock);
> +
> +	return ret;
> +}
> +
> +static int ptn36502_retimer_set(struct typec_retimer *retimer, struct typec_retimer_state *state)
> +{
> +	struct ptn36502 *ptn = typec_retimer_get_drvdata(retimer);
> +	int ret = 0;
> +
> +	mutex_lock(&ptn->lock);
> +
> +	if (ptn->mode != state->mode) {
> +		ptn->mode = state->mode;
> +
> +		if (state->alt)
> +			ptn->svid = state->alt->svid;
> +		else
> +			ptn->svid = 0; // No SVID
> +
> +		ret = ptn36502_set(ptn);
> +	}
> +
> +	mutex_unlock(&ptn->lock);
> +
> +	return ret;
> +}
> +
> +static int ptn36502_detect(struct ptn36502 *ptn)
> +{
> +	struct device *dev = &ptn->client->dev;
> +	unsigned int reg_val;
> +	int ret;
> +
> +	ret = regmap_read(ptn->regmap, PTN36502_CHIP_ID_REG,
> +			  &reg_val);
> +	if (ret < 0)
> +		return dev_err_probe(dev, ret, "Failed to read chip ID\n");
> +
> +	if (reg_val != PTN36502_CHIP_ID)
> +		return dev_err_probe(dev, -ENODEV, "Unexpected chip ID: %x\n", reg_val);
> +
> +	ret = regmap_read(ptn->regmap, PTN36502_CHIP_REVISION_REG,
> +			  &reg_val);
> +	if (ret < 0)
> +		return dev_err_probe(dev, ret, "Failed to read chip revision\n");
> +
> +	dev_dbg(dev, "Chip revision: base layer version %lx, metal layer version %lx\n",
> +		PTN36502_CHIP_REVISION_BASE(reg_val),
> +		PTN36502_CHIP_REVISION_METAL(reg_val));
> +
> +	return 0;
> +}
> +
> +#if IS_ENABLED(CONFIG_OF) && IS_ENABLED(CONFIG_DRM_PANEL_BRIDGE)
> +static int ptn36502_bridge_attach(struct drm_bridge *bridge,
> +				    enum drm_bridge_attach_flags flags)

I applied this patch and realised that that's not correctly aligned.
There are couple of extra spaces.

> +{
> +	struct ptn36502 *ptn = container_of(bridge, struct ptn36502, bridge);
> +	struct drm_bridge *next_bridge;
> +
> +	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
> +		return -EINVAL;
> +
> +	next_bridge = devm_drm_of_get_bridge(&ptn->client->dev, ptn->client->dev.of_node, 0, 0);
> +	if (IS_ERR(next_bridge)) {
> +		dev_err(&ptn->client->dev, "failed to acquire drm_bridge: %pe\n", next_bridge);
> +		return PTR_ERR(next_bridge);
> +	}
> +
> +	return drm_bridge_attach(bridge->encoder, next_bridge, bridge,
> +				 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
> +}
> +
> +static const struct drm_bridge_funcs ptn36502_bridge_funcs = {
> +	.attach	= ptn36502_bridge_attach,
> +};
> +
> +static int ptn36502_register_bridge(struct ptn36502 *ptn)
> +{
> +	ptn->bridge.funcs = &ptn36502_bridge_funcs;
> +	ptn->bridge.of_node = ptn->client->dev.of_node;
> +
> +	return devm_drm_bridge_add(&ptn->client->dev, &ptn->bridge);
> +}
> +#else
> +static int ptn36502_register_bridge(struct ptn36502 *ptn)
> +{
> +	return 0;
> +}
> +#endif
> +
> +static const struct regmap_config ptn36502_regmap = {
> +	.max_register = 0x0d,
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +};
> +
> +static int ptn36502_probe(struct i2c_client *client)
> +{
> +	struct device *dev = &client->dev;
> +	struct typec_switch_desc sw_desc = { };
> +	struct typec_retimer_desc retimer_desc = { };
> +	struct ptn36502 *ptn;
> +	int ret;
> +
> +	ptn = devm_kzalloc(dev, sizeof(*ptn), GFP_KERNEL);
> +	if (!ptn)
> +		return -ENOMEM;
> +
> +	ptn->client = client;
> +
> +	ptn->regmap = devm_regmap_init_i2c(client, &ptn36502_regmap);
> +	if (IS_ERR(ptn->regmap)) {
> +		dev_err(&client->dev, "Failed to allocate register map\n");
> +		return PTR_ERR(ptn->regmap);
> +	}
> +
> +	ptn->mode = TYPEC_STATE_SAFE;
> +	ptn->orientation = TYPEC_ORIENTATION_NONE;
> +
> +	mutex_init(&ptn->lock);
> +
> +	ptn->vdd18_supply = devm_regulator_get_optional(dev, "vdd18");
> +	if (IS_ERR(ptn->vdd18_supply))
> +		return PTR_ERR(ptn->vdd18_supply);
> +
> +	ptn->typec_switch = fwnode_typec_switch_get(dev->fwnode);
> +	if (IS_ERR(ptn->typec_switch))
> +		return dev_err_probe(dev, PTR_ERR(ptn->typec_switch),
> +				     "Failed to acquire orientation-switch\n");
> +
> +	ret = regulator_enable(ptn->vdd18_supply);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "Failed to enable vdd18\n");
> +
> +	ret = ptn36502_detect(ptn);
> +	if (ret)
> +		goto err_disable_regulator;
> +
> +	ret = ptn36502_register_bridge(ptn);
> +	if (ret)
> +		goto err_disable_regulator;
> +
> +	sw_desc.drvdata = ptn;
> +	sw_desc.fwnode = dev->fwnode;
> +	sw_desc.set = ptn36502_sw_set;
> +
> +	ptn->sw = typec_switch_register(dev, &sw_desc);
> +	if (IS_ERR(ptn->sw)) {
> +		ret = dev_err_probe(dev, PTR_ERR(ptn->sw),
> +				    "Failed to register typec switch\n");
> +		goto err_disable_regulator;
> +	}
> +
> +	retimer_desc.drvdata = ptn;
> +	retimer_desc.fwnode = dev->fwnode;
> +	retimer_desc.set = ptn36502_retimer_set;
> +
> +	ptn->retimer = typec_retimer_register(dev, &retimer_desc);
> +	if (IS_ERR(ptn->retimer)) {
> +		ret = dev_err_probe(dev, PTR_ERR(ptn->retimer),
> +				    "Failed to register typec retimer\n");
> +		goto err_switch_unregister;
> +	}
> +
> +	return 0;
> +
> +err_switch_unregister:
> +	typec_switch_unregister(ptn->sw);
> +
> +err_disable_regulator:
> +	regulator_disable(ptn->vdd18_supply);
> +
> +	return ret;
> +}
> +
> +static void ptn36502_remove(struct i2c_client *client)
> +{
> +	struct ptn36502 *ptn = i2c_get_clientdata(client);
> +
> +	typec_retimer_unregister(ptn->retimer);
> +	typec_switch_unregister(ptn->sw);
> +
> +	regulator_disable(ptn->vdd18_supply);
> +}
> +
> +static const struct i2c_device_id ptn36502_table[] = {
> +	{ "ptn36502" },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(i2c, ptn36502_table);
> +
> +static const struct of_device_id ptn36502_of_table[] = {
> +	{ .compatible = "nxp,ptn36502" },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(of, ptn36502_of_table);
> +
> +static struct i2c_driver ptn36502_driver = {
> +	.driver = {
> +		.name = "ptn36502",
> +		.of_match_table = ptn36502_of_table,
> +	},
> +	.probe		= ptn36502_probe,
> +	.remove		= ptn36502_remove,
> +	.id_table	= ptn36502_table,
> +};
> +module_i2c_driver(ptn36502_driver);
> +
> +MODULE_AUTHOR("Luca Weiss <luca.weiss@fairphone.com>");
> +MODULE_DESCRIPTION("NXP PTN36502 Type-C driver");
> +MODULE_LICENSE("GPL");

thanks,

-- 
heikki

Re: [PATCH 2/2] usb: typec: add support for PTN36502 redriver

[Luca Weiss]

On Tue Oct 17, 2023 at 10:34 AM CEST, Heikki Krogerus wrote:
> Hi,
>
> On Fri, Oct 13, 2023 at 04:24:48PM +0200, Luca Weiss wrote:
> > Add a driver for the NXP PTN36502 Type-C USB 3.1 Gen 1 and DisplayPort
> > v1.2 combo redriver.
> > 
> > Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
>
> Looks OK to me, but couple of nitpicks below. With those fixed:
>
> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
>
> > ---
> >  drivers/usb/typec/mux/Kconfig    |  10 +
> >  drivers/usb/typec/mux/Makefile   |   1 +
> >  drivers/usb/typec/mux/ptn36502.c | 421 +++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 432 insertions(+)
> > 
> > diff --git a/drivers/usb/typec/mux/Kconfig b/drivers/usb/typec/mux/Kconfig
> > index 65da61150ba7..816b9bd08355 100644
> > --- a/drivers/usb/typec/mux/Kconfig
> > +++ b/drivers/usb/typec/mux/Kconfig
> > @@ -46,4 +46,14 @@ config TYPEC_MUX_NB7VPQ904M
> >  	  Say Y or M if your system has a On Semiconductor NB7VPQ904M Type-C
> >  	  redriver chip found on some devices with a Type-C port.
> >  
> > +config TYPEC_MUX_PTN36502
> > +	tristate "NXP PTN36502 Type-C redriver driver"
> > +	depends on I2C
> > +	depends on DRM || DRM=n
> > +	select DRM_PANEL_BRIDGE if DRM
> > +	select REGMAP_I2C
> > +	help
> > +	  Say Y or M if your system has a NXP PTN36502 Type-C redriver chip
> > +	  found on some devices with a Type-C port.
> > +
> >  endmenu
> > diff --git a/drivers/usb/typec/mux/Makefile b/drivers/usb/typec/mux/Makefile
> > index 76196096ef41..9d6a5557b0bd 100644
> > --- a/drivers/usb/typec/mux/Makefile
> > +++ b/drivers/usb/typec/mux/Makefile
> > @@ -5,3 +5,4 @@ obj-$(CONFIG_TYPEC_MUX_GPIO_SBU)	+= gpio-sbu-mux.o
> >  obj-$(CONFIG_TYPEC_MUX_PI3USB30532)	+= pi3usb30532.o
> >  obj-$(CONFIG_TYPEC_MUX_INTEL_PMC)	+= intel_pmc_mux.o
> >  obj-$(CONFIG_TYPEC_MUX_NB7VPQ904M)	+= nb7vpq904m.o
> > +obj-$(CONFIG_TYPEC_MUX_PTN36502)	+= ptn36502.o
> > diff --git a/drivers/usb/typec/mux/ptn36502.c b/drivers/usb/typec/mux/ptn36502.c
> > new file mode 100644
> > index 000000000000..91684a856f3a
> > --- /dev/null
> > +++ b/drivers/usb/typec/mux/ptn36502.c
> > @@ -0,0 +1,421 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * NXP PTN36502 Type-C driver
> > + *
> > + * Copyright (C) 2023 Luca Weiss <luca.weiss@fairphone.com>
> > + *
> > + * Based on NB7VPQ904M driver:
> > + * Copyright (C) 2023 Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > + */
> > +
> > +#include <drm/drm_bridge.h>
> > +#include <linux/bitfield.h>
> > +#include <linux/i2c.h>
> > +#include <linux/kernel.h>
> > +#include <linux/module.h>
> > +#include <linux/mutex.h>
> > +#include <linux/of_graph.h>
> > +#include <linux/regmap.h>
> > +#include <linux/regulator/consumer.h>
> > +#include <linux/usb/typec_dp.h>
> > +#include <linux/usb/typec_mux.h>
> > +#include <linux/usb/typec_retimer.h>
> > +
> > +#define PTN36502_CHIP_ID_REG				0x00
> > +#define PTN36502_CHIP_ID				0x02
> > +
> > +#define PTN36502_CHIP_REVISION_REG			0x01
> > +#define PTN36502_CHIP_REVISION_BASE(val)		FIELD_GET(GENMASK(7, 4), (val))
> > +#define PTN36502_CHIP_REVISION_METAL(val)		FIELD_GET(GENMASK(3, 0), (val))
> > +
> > +#define PTN36502_DP_LINK_CTRL_REG			0x06
> > +#define PTN36502_DP_LINK_CTRL_LANES_2			(2 << 2)
> > +#define PTN36502_DP_LINK_CTRL_LANES_4			(3 << 2)
> > +#define PTN36502_DP_LINK_CTRL_LINK_RATE_5_4GBPS		(2 << 0)
> > +
> > +/* Registers for lane 0 (0x07) to lane 3 (0x0a) have the same layout */
> > +#define PTN36502_DP_LANE_CTRL_REG(n)			(0x07 + (n))
> > +#define PTN36502_DP_LANE_CTRL_RX_GAIN_3DB		(2<<4)
> > +#define PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD		(2<<2)
> > +#define PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_3_5DB	(1<<0)
> > +
> > +#define PTN36502_MODE_CTRL1_REG				0x0b
> > +#define PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE		(1<<5)
> > +#define PTN36502_MODE_CTRL1_AUX_CROSSBAR_SW_ON		(1<<3)
> > +#define PTN36502_MODE_CTRL1_MODE_OFF			(0<<0)
> > +#define PTN36502_MODE_CTRL1_MODE_USB_ONLY		(1<<0)
> > +#define PTN36502_MODE_CTRL1_MODE_USB_DP			(2<<0)
> > +#define PTN36502_MODE_CTRL1_MODE_DP			(3<<0)
> > +
> > +#define PTN36502_DEVICE_CTRL_REG			0x0d
> > +#define PTN36502_DEVICE_CTRL_AUX_MONITORING_EN		(1<<7)
>
> You have couple of different styles here. Please try to always use
> BIT() and GENMASK() macros when possible. At the very least put spaces
> around << and >>.

Hi Heikki,

I was wondering when writing that whether GENMASK was actually proper
use for values you write to registers, when not actually used as a
bitmask.

Since the datasheet refers to e.g. with TX_SWING_800MVPPD (2<<2) that
you write a '2' to the correct bits of this register. But when using
BIT(3) kind of hides this relationship if someone refers back to the
datasheet. Or same with "3<<2" -> GENMASK(3, 2) or whatever.

Let me know what you think.

Regards
Luca

>
> > +struct ptn36502 {
> > +	struct i2c_client *client;
> > +	struct regulator *vdd18_supply;
> > +	struct regmap *regmap;
> > +	struct typec_switch_dev *sw;
> > +	struct typec_retimer *retimer;
> > +
> > +	struct typec_switch *typec_switch;
> > +
> > +	struct drm_bridge bridge;
> > +
> > +	struct mutex lock; /* protect non-concurrent retimer & switch */
> > +
> > +	enum typec_orientation orientation;
> > +	unsigned long mode;
> > +	unsigned int svid;
> > +};
> > +
> > +static int ptn36502_set(struct ptn36502 *ptn)
> > +{
> > +	bool reverse = (ptn->orientation == TYPEC_ORIENTATION_REVERSE);
> > +	unsigned int ctrl1_val = 0;
> > +	unsigned int lane_ctrl_val = 0;
> > +	unsigned int link_ctrl_val = 0;
> > +
> > +	switch (ptn->mode) {
> > +	case TYPEC_STATE_SAFE:
> > +		/* Deep power saving state */
> > +		regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG,
> > +			     PTN36502_MODE_CTRL1_MODE_OFF);
> > +		return 0;
> > +
> > +	case TYPEC_STATE_USB:
> > +		/*
> > +		 * Normal Orientation (CC1)
> > +		 * A -> USB RX
> > +		 * B -> USB TX
> > +		 * C -> X
> > +		 * D -> X
> > +		 * Flipped Orientation (CC2)
> > +		 * A -> X
> > +		 * B -> X
> > +		 * C -> USB TX
> > +		 * D -> USB RX
> > +		 */
> > +
> > +		/* USB 3.1 Gen 1 only */
> > +		ctrl1_val = PTN36502_MODE_CTRL1_MODE_USB_ONLY;
> > +		if (reverse)
> > +			ctrl1_val |= PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE;
> > +
> > +		regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG, ctrl1_val);
> > +		return 0;
> > +
> > +	default:
> > +		if (ptn->svid != USB_TYPEC_DP_SID)
> > +			return -EINVAL;
> > +
> > +		break;
> > +	}
> > +
> > +	/* DP Altmode Setup */
> > +
> > +	switch (ptn->mode) {
> > +	case TYPEC_DP_STATE_C:
> > +	case TYPEC_DP_STATE_E:
> > +		/*
> > +		 * Normal Orientation (CC1)
> > +		 * A -> DP3
> > +		 * B -> DP2
> > +		 * C -> DP1
> > +		 * D -> DP0
> > +		 * Flipped Orientation (CC2)
> > +		 * A -> DP0
> > +		 * B -> DP1
> > +		 * C -> DP2
> > +		 * D -> DP3
> > +		 */
> > +
> > +		/* 4-lane DP */
> > +		ctrl1_val |= PTN36502_MODE_CTRL1_MODE_DP;
> > +		link_ctrl_val |= PTN36502_DP_LINK_CTRL_LANES_4;
> > +		break;
> > +
> > +	case TYPEC_DP_STATE_D:
> > +	case TYPEC_DP_STATE_F: /* State F is deprecated */
> > +		/*
> > +		 * Normal Orientation (CC1)
> > +		 * A -> USB RX
> > +		 * B -> USB TX
> > +		 * C -> DP1
> > +		 * D -> DP0
> > +		 * Flipped Orientation (CC2)
> > +		 * A -> DP0
> > +		 * B -> DP1
> > +		 * C -> USB TX
> > +		 * D -> USB RX
> > +		 */
> > +
> > +		/* USB 3.1 Gen 1 and 2-lane DP */
> > +		ctrl1_val |= PTN36502_MODE_CTRL1_MODE_USB_DP;
> > +		link_ctrl_val |= PTN36502_DP_LINK_CTRL_LANES_2;
> > +		break;
> > +
> > +	default:
> > +		return -EOPNOTSUPP;
> > +	}
> > +
> > +	/* Enable AUX monitoring */
> > +	regmap_write(ptn->regmap, PTN36502_DEVICE_CTRL_REG,
> > +		     PTN36502_DEVICE_CTRL_AUX_MONITORING_EN);
> > +
> > +	/* Enable AUX switch path */
> > +	ctrl1_val |= PTN36502_MODE_CTRL1_AUX_CROSSBAR_SW_ON;
> > +	if (reverse)
> > +		ctrl1_val |= PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE;
> > +	regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG, ctrl1_val);
> > +
> > +	/* DP Link rate: 5.4 Gbps (HBR2) */
> > +	link_ctrl_val |= PTN36502_DP_LINK_CTRL_LINK_RATE_5_4GBPS;
> > +	regmap_write(ptn->regmap, PTN36502_DP_LINK_CTRL_REG, link_ctrl_val);
> > +
> > +	/*
> > +	 * For all lanes:
> > +	 * - Rx equivalization gain: 3 dB
> > +	 * - TX output swing control: 800 mVppd
> > +	 * - Pre-emphasis control: 3.5 dB
> > +	 */
> > +	lane_ctrl_val = PTN36502_DP_LANE_CTRL_RX_GAIN_3DB |
> > +			PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD |
> > +			PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_3_5DB;
> > +	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(0), lane_ctrl_val);
> > +	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(1), lane_ctrl_val);
> > +	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(2), lane_ctrl_val);
> > +	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(3), lane_ctrl_val);
> > +
> > +	return 0;
> > +}
> > +
> > +static int ptn36502_sw_set(struct typec_switch_dev *sw, enum typec_orientation orientation)
> > +{
> > +	struct ptn36502 *ptn = typec_switch_get_drvdata(sw);
> > +	int ret;
> > +
> > +	ret = typec_switch_set(ptn->typec_switch, orientation);
> > +	if (ret)
> > +		return ret;
> > +
> > +	mutex_lock(&ptn->lock);
> > +
> > +	if (ptn->orientation != orientation) {
> > +		ptn->orientation = orientation;
> > +
> > +		ret = ptn36502_set(ptn);
> > +	}
> > +
> > +	mutex_unlock(&ptn->lock);
> > +
> > +	return ret;
> > +}
> > +
> > +static int ptn36502_retimer_set(struct typec_retimer *retimer, struct typec_retimer_state *state)
> > +{
> > +	struct ptn36502 *ptn = typec_retimer_get_drvdata(retimer);
> > +	int ret = 0;
> > +
> > +	mutex_lock(&ptn->lock);
> > +
> > +	if (ptn->mode != state->mode) {
> > +		ptn->mode = state->mode;
> > +
> > +		if (state->alt)
> > +			ptn->svid = state->alt->svid;
> > +		else
> > +			ptn->svid = 0; // No SVID
> > +
> > +		ret = ptn36502_set(ptn);
> > +	}
> > +
> > +	mutex_unlock(&ptn->lock);
> > +
> > +	return ret;
> > +}
> > +
> > +static int ptn36502_detect(struct ptn36502 *ptn)
> > +{
> > +	struct device *dev = &ptn->client->dev;
> > +	unsigned int reg_val;
> > +	int ret;
> > +
> > +	ret = regmap_read(ptn->regmap, PTN36502_CHIP_ID_REG,
> > +			  &reg_val);
> > +	if (ret < 0)
> > +		return dev_err_probe(dev, ret, "Failed to read chip ID\n");
> > +
> > +	if (reg_val != PTN36502_CHIP_ID)
> > +		return dev_err_probe(dev, -ENODEV, "Unexpected chip ID: %x\n", reg_val);
> > +
> > +	ret = regmap_read(ptn->regmap, PTN36502_CHIP_REVISION_REG,
> > +			  &reg_val);
> > +	if (ret < 0)
> > +		return dev_err_probe(dev, ret, "Failed to read chip revision\n");
> > +
> > +	dev_dbg(dev, "Chip revision: base layer version %lx, metal layer version %lx\n",
> > +		PTN36502_CHIP_REVISION_BASE(reg_val),
> > +		PTN36502_CHIP_REVISION_METAL(reg_val));
> > +
> > +	return 0;
> > +}
> > +
> > +#if IS_ENABLED(CONFIG_OF) && IS_ENABLED(CONFIG_DRM_PANEL_BRIDGE)
> > +static int ptn36502_bridge_attach(struct drm_bridge *bridge,
> > +				    enum drm_bridge_attach_flags flags)
>
> I applied this patch and realised that that's not correctly aligned.
> There are couple of extra spaces.
>
> > +{
> > +	struct ptn36502 *ptn = container_of(bridge, struct ptn36502, bridge);
> > +	struct drm_bridge *next_bridge;
> > +
> > +	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
> > +		return -EINVAL;
> > +
> > +	next_bridge = devm_drm_of_get_bridge(&ptn->client->dev, ptn->client->dev.of_node, 0, 0);
> > +	if (IS_ERR(next_bridge)) {
> > +		dev_err(&ptn->client->dev, "failed to acquire drm_bridge: %pe\n", next_bridge);
> > +		return PTR_ERR(next_bridge);
> > +	}
> > +
> > +	return drm_bridge_attach(bridge->encoder, next_bridge, bridge,
> > +				 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
> > +}
> > +
> > +static const struct drm_bridge_funcs ptn36502_bridge_funcs = {
> > +	.attach	= ptn36502_bridge_attach,
> > +};
> > +
> > +static int ptn36502_register_bridge(struct ptn36502 *ptn)
> > +{
> > +	ptn->bridge.funcs = &ptn36502_bridge_funcs;
> > +	ptn->bridge.of_node = ptn->client->dev.of_node;
> > +
> > +	return devm_drm_bridge_add(&ptn->client->dev, &ptn->bridge);
> > +}
> > +#else
> > +static int ptn36502_register_bridge(struct ptn36502 *ptn)
> > +{
> > +	return 0;
> > +}
> > +#endif
> > +
> > +static const struct regmap_config ptn36502_regmap = {
> > +	.max_register = 0x0d,
> > +	.reg_bits = 8,
> > +	.val_bits = 8,
> > +};
> > +
> > +static int ptn36502_probe(struct i2c_client *client)
> > +{
> > +	struct device *dev = &client->dev;
> > +	struct typec_switch_desc sw_desc = { };
> > +	struct typec_retimer_desc retimer_desc = { };
> > +	struct ptn36502 *ptn;
> > +	int ret;
> > +
> > +	ptn = devm_kzalloc(dev, sizeof(*ptn), GFP_KERNEL);
> > +	if (!ptn)
> > +		return -ENOMEM;
> > +
> > +	ptn->client = client;
> > +
> > +	ptn->regmap = devm_regmap_init_i2c(client, &ptn36502_regmap);
> > +	if (IS_ERR(ptn->regmap)) {
> > +		dev_err(&client->dev, "Failed to allocate register map\n");
> > +		return PTR_ERR(ptn->regmap);
> > +	}
> > +
> > +	ptn->mode = TYPEC_STATE_SAFE;
> > +	ptn->orientation = TYPEC_ORIENTATION_NONE;
> > +
> > +	mutex_init(&ptn->lock);
> > +
> > +	ptn->vdd18_supply = devm_regulator_get_optional(dev, "vdd18");
> > +	if (IS_ERR(ptn->vdd18_supply))
> > +		return PTR_ERR(ptn->vdd18_supply);
> > +
> > +	ptn->typec_switch = fwnode_typec_switch_get(dev->fwnode);
> > +	if (IS_ERR(ptn->typec_switch))
> > +		return dev_err_probe(dev, PTR_ERR(ptn->typec_switch),
> > +				     "Failed to acquire orientation-switch\n");
> > +
> > +	ret = regulator_enable(ptn->vdd18_supply);
> > +	if (ret)
> > +		return dev_err_probe(dev, ret, "Failed to enable vdd18\n");
> > +
> > +	ret = ptn36502_detect(ptn);
> > +	if (ret)
> > +		goto err_disable_regulator;
> > +
> > +	ret = ptn36502_register_bridge(ptn);
> > +	if (ret)
> > +		goto err_disable_regulator;
> > +
> > +	sw_desc.drvdata = ptn;
> > +	sw_desc.fwnode = dev->fwnode;
> > +	sw_desc.set = ptn36502_sw_set;
> > +
> > +	ptn->sw = typec_switch_register(dev, &sw_desc);
> > +	if (IS_ERR(ptn->sw)) {
> > +		ret = dev_err_probe(dev, PTR_ERR(ptn->sw),
> > +				    "Failed to register typec switch\n");
> > +		goto err_disable_regulator;
> > +	}
> > +
> > +	retimer_desc.drvdata = ptn;
> > +	retimer_desc.fwnode = dev->fwnode;
> > +	retimer_desc.set = ptn36502_retimer_set;
> > +
> > +	ptn->retimer = typec_retimer_register(dev, &retimer_desc);
> > +	if (IS_ERR(ptn->retimer)) {
> > +		ret = dev_err_probe(dev, PTR_ERR(ptn->retimer),
> > +				    "Failed to register typec retimer\n");
> > +		goto err_switch_unregister;
> > +	}
> > +
> > +	return 0;
> > +
> > +err_switch_unregister:
> > +	typec_switch_unregister(ptn->sw);
> > +
> > +err_disable_regulator:
> > +	regulator_disable(ptn->vdd18_supply);
> > +
> > +	return ret;
> > +}
> > +
> > +static void ptn36502_remove(struct i2c_client *client)
> > +{
> > +	struct ptn36502 *ptn = i2c_get_clientdata(client);
> > +
> > +	typec_retimer_unregister(ptn->retimer);
> > +	typec_switch_unregister(ptn->sw);
> > +
> > +	regulator_disable(ptn->vdd18_supply);
> > +}
> > +
> > +static const struct i2c_device_id ptn36502_table[] = {
> > +	{ "ptn36502" },
> > +	{ }
> > +};
> > +MODULE_DEVICE_TABLE(i2c, ptn36502_table);
> > +
> > +static const struct of_device_id ptn36502_of_table[] = {
> > +	{ .compatible = "nxp,ptn36502" },
> > +	{ }
> > +};
> > +MODULE_DEVICE_TABLE(of, ptn36502_of_table);
> > +
> > +static struct i2c_driver ptn36502_driver = {
> > +	.driver = {
> > +		.name = "ptn36502",
> > +		.of_match_table = ptn36502_of_table,
> > +	},
> > +	.probe		= ptn36502_probe,
> > +	.remove		= ptn36502_remove,
> > +	.id_table	= ptn36502_table,
> > +};
> > +module_i2c_driver(ptn36502_driver);
> > +
> > +MODULE_AUTHOR("Luca Weiss <luca.weiss@fairphone.com>");
> > +MODULE_DESCRIPTION("NXP PTN36502 Type-C driver");
> > +MODULE_LICENSE("GPL");
>
> thanks,

Re: [PATCH 2/2] usb: typec: add support for PTN36502 redriver

[Neil Armstrong]

On 20/10/2023 08:13, Luca Weiss wrote:
> On Tue Oct 17, 2023 at 10:34 AM CEST, Heikki Krogerus wrote:
>> Hi,
>>
>> On Fri, Oct 13, 2023 at 04:24:48PM +0200, Luca Weiss wrote:
>>> Add a driver for the NXP PTN36502 Type-C USB 3.1 Gen 1 and DisplayPort
>>> v1.2 combo redriver.
>>>
>>> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
>>
>> Looks OK to me, but couple of nitpicks below. With those fixed:
>>
>> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
>>
>>> ---
>>>   drivers/usb/typec/mux/Kconfig    |  10 +
>>>   drivers/usb/typec/mux/Makefile   |   1 +
>>>   drivers/usb/typec/mux/ptn36502.c | 421 +++++++++++++++++++++++++++++++++++++++
>>>   3 files changed, 432 insertions(+)
>>>
>>> diff --git a/drivers/usb/typec/mux/Kconfig b/drivers/usb/typec/mux/Kconfig
>>> index 65da61150ba7..816b9bd08355 100644
>>> --- a/drivers/usb/typec/mux/Kconfig
>>> +++ b/drivers/usb/typec/mux/Kconfig
>>> @@ -46,4 +46,14 @@ config TYPEC_MUX_NB7VPQ904M
>>>   	  Say Y or M if your system has a On Semiconductor NB7VPQ904M Type-C
>>>   	  redriver chip found on some devices with a Type-C port.
>>>   
>>> +config TYPEC_MUX_PTN36502
>>> +	tristate "NXP PTN36502 Type-C redriver driver"
>>> +	depends on I2C
>>> +	depends on DRM || DRM=n
>>> +	select DRM_PANEL_BRIDGE if DRM
>>> +	select REGMAP_I2C
>>> +	help
>>> +	  Say Y or M if your system has a NXP PTN36502 Type-C redriver chip
>>> +	  found on some devices with a Type-C port.
>>> +
>>>   endmenu
>>> diff --git a/drivers/usb/typec/mux/Makefile b/drivers/usb/typec/mux/Makefile
>>> index 76196096ef41..9d6a5557b0bd 100644
>>> --- a/drivers/usb/typec/mux/Makefile
>>> +++ b/drivers/usb/typec/mux/Makefile
>>> @@ -5,3 +5,4 @@ obj-$(CONFIG_TYPEC_MUX_GPIO_SBU)	+= gpio-sbu-mux.o
>>>   obj-$(CONFIG_TYPEC_MUX_PI3USB30532)	+= pi3usb30532.o
>>>   obj-$(CONFIG_TYPEC_MUX_INTEL_PMC)	+= intel_pmc_mux.o
>>>   obj-$(CONFIG_TYPEC_MUX_NB7VPQ904M)	+= nb7vpq904m.o
>>> +obj-$(CONFIG_TYPEC_MUX_PTN36502)	+= ptn36502.o
>>> diff --git a/drivers/usb/typec/mux/ptn36502.c b/drivers/usb/typec/mux/ptn36502.c
>>> new file mode 100644
>>> index 000000000000..91684a856f3a
>>> --- /dev/null
>>> +++ b/drivers/usb/typec/mux/ptn36502.c
>>> @@ -0,0 +1,421 @@
>>> +// SPDX-License-Identifier: GPL-2.0+
>>> +/*
>>> + * NXP PTN36502 Type-C driver
>>> + *
>>> + * Copyright (C) 2023 Luca Weiss <luca.weiss@fairphone.com>
>>> + *
>>> + * Based on NB7VPQ904M driver:
>>> + * Copyright (C) 2023 Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>>> + */
>>> +
>>> +#include <drm/drm_bridge.h>
>>> +#include <linux/bitfield.h>
>>> +#include <linux/i2c.h>
>>> +#include <linux/kernel.h>
>>> +#include <linux/module.h>
>>> +#include <linux/mutex.h>
>>> +#include <linux/of_graph.h>
>>> +#include <linux/regmap.h>
>>> +#include <linux/regulator/consumer.h>
>>> +#include <linux/usb/typec_dp.h>
>>> +#include <linux/usb/typec_mux.h>
>>> +#include <linux/usb/typec_retimer.h>
>>> +
>>> +#define PTN36502_CHIP_ID_REG				0x00
>>> +#define PTN36502_CHIP_ID				0x02
>>> +
>>> +#define PTN36502_CHIP_REVISION_REG			0x01
>>> +#define PTN36502_CHIP_REVISION_BASE(val)		FIELD_GET(GENMASK(7, 4), (val))
>>> +#define PTN36502_CHIP_REVISION_METAL(val)		FIELD_GET(GENMASK(3, 0), (val))
>>> +
>>> +#define PTN36502_DP_LINK_CTRL_REG			0x06
>>> +#define PTN36502_DP_LINK_CTRL_LANES_2			(2 << 2)
>>> +#define PTN36502_DP_LINK_CTRL_LANES_4			(3 << 2)
>>> +#define PTN36502_DP_LINK_CTRL_LINK_RATE_5_4GBPS		(2 << 0)
>>> +
>>> +/* Registers for lane 0 (0x07) to lane 3 (0x0a) have the same layout */
>>> +#define PTN36502_DP_LANE_CTRL_REG(n)			(0x07 + (n))
>>> +#define PTN36502_DP_LANE_CTRL_RX_GAIN_3DB		(2<<4)
>>> +#define PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD		(2<<2)
>>> +#define PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_3_5DB	(1<<0)
>>> +
>>> +#define PTN36502_MODE_CTRL1_REG				0x0b
>>> +#define PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE		(1<<5)
>>> +#define PTN36502_MODE_CTRL1_AUX_CROSSBAR_SW_ON		(1<<3)
>>> +#define PTN36502_MODE_CTRL1_MODE_OFF			(0<<0)
>>> +#define PTN36502_MODE_CTRL1_MODE_USB_ONLY		(1<<0)
>>> +#define PTN36502_MODE_CTRL1_MODE_USB_DP			(2<<0)
>>> +#define PTN36502_MODE_CTRL1_MODE_DP			(3<<0)
>>> +
>>> +#define PTN36502_DEVICE_CTRL_REG			0x0d
>>> +#define PTN36502_DEVICE_CTRL_AUX_MONITORING_EN		(1<<7)
>>
>> You have couple of different styles here. Please try to always use
>> BIT() and GENMASK() macros when possible. At the very least put spaces
>> around << and >>.
> 
> Hi Heikki,
> 
> I was wondering when writing that whether GENMASK was actually proper
> use for values you write to registers, when not actually used as a
> bitmask.
> 
> Since the datasheet refers to e.g. with TX_SWING_800MVPPD (2<<2) that
> you write a '2' to the correct bits of this register. But when using
> BIT(3) kind of hides this relationship if someone refers back to the
> datasheet. Or same with "3<<2" -> GENMASK(3, 2) or whatever.

The proper way is to define the MASK for the field GENMASK(3, 2) and then
use FIELD_PREP(GENMASK(3, 2), 2) to write 2 in this field.

You could replace with:
#define PTN36502_DP_LANE_CTRL_TX_SWING_MASK		GENMASK(3, 2)
#define PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD		(2)

and in the code
lane_ctrl_val = FIELD_PREP(PTN36502_DP_LANE_CTRL_RX_GAIN_MASK,
			   PTN36502_DP_LANE_CTRL_RX_GAIN_3DB) |
		FIELD_PREP(PTN36502_DP_LANE_CTRL_TX_SWING_MASK,
			   PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD) |
		FIELD_PREP(PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_MASK,
			   PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_3_5DB);

It's a little more verbose but it's much clearer and defines stuff correctly,
no confusion possible.

Neil

> 
> Let me know what you think.
> 
> Regards
> Luca
> 
>>
>>> +struct ptn36502 {
>>> +	struct i2c_client *client;
>>> +	struct regulator *vdd18_supply;
>>> +	struct regmap *regmap;
>>> +	struct typec_switch_dev *sw;
>>> +	struct typec_retimer *retimer;
>>> +
>>> +	struct typec_switch *typec_switch;
>>> +
>>> +	struct drm_bridge bridge;
>>> +
>>> +	struct mutex lock; /* protect non-concurrent retimer & switch */
>>> +
>>> +	enum typec_orientation orientation;
>>> +	unsigned long mode;
>>> +	unsigned int svid;
>>> +};
>>> +
>>> +static int ptn36502_set(struct ptn36502 *ptn)
>>> +{
>>> +	bool reverse = (ptn->orientation == TYPEC_ORIENTATION_REVERSE);
>>> +	unsigned int ctrl1_val = 0;
>>> +	unsigned int lane_ctrl_val = 0;
>>> +	unsigned int link_ctrl_val = 0;
>>> +
>>> +	switch (ptn->mode) {
>>> +	case TYPEC_STATE_SAFE:
>>> +		/* Deep power saving state */
>>> +		regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG,
>>> +			     PTN36502_MODE_CTRL1_MODE_OFF);
>>> +		return 0;
>>> +
>>> +	case TYPEC_STATE_USB:
>>> +		/*
>>> +		 * Normal Orientation (CC1)
>>> +		 * A -> USB RX
>>> +		 * B -> USB TX
>>> +		 * C -> X
>>> +		 * D -> X
>>> +		 * Flipped Orientation (CC2)
>>> +		 * A -> X
>>> +		 * B -> X
>>> +		 * C -> USB TX
>>> +		 * D -> USB RX
>>> +		 */
>>> +
>>> +		/* USB 3.1 Gen 1 only */
>>> +		ctrl1_val = PTN36502_MODE_CTRL1_MODE_USB_ONLY;
>>> +		if (reverse)
>>> +			ctrl1_val |= PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE;
>>> +
>>> +		regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG, ctrl1_val);
>>> +		return 0;
>>> +
>>> +	default:
>>> +		if (ptn->svid != USB_TYPEC_DP_SID)
>>> +			return -EINVAL;
>>> +
>>> +		break;
>>> +	}
>>> +
>>> +	/* DP Altmode Setup */
>>> +
>>> +	switch (ptn->mode) {
>>> +	case TYPEC_DP_STATE_C:
>>> +	case TYPEC_DP_STATE_E:
>>> +		/*
>>> +		 * Normal Orientation (CC1)
>>> +		 * A -> DP3
>>> +		 * B -> DP2
>>> +		 * C -> DP1
>>> +		 * D -> DP0
>>> +		 * Flipped Orientation (CC2)
>>> +		 * A -> DP0
>>> +		 * B -> DP1
>>> +		 * C -> DP2
>>> +		 * D -> DP3
>>> +		 */
>>> +
>>> +		/* 4-lane DP */
>>> +		ctrl1_val |= PTN36502_MODE_CTRL1_MODE_DP;
>>> +		link_ctrl_val |= PTN36502_DP_LINK_CTRL_LANES_4;
>>> +		break;
>>> +
>>> +	case TYPEC_DP_STATE_D:
>>> +	case TYPEC_DP_STATE_F: /* State F is deprecated */
>>> +		/*
>>> +		 * Normal Orientation (CC1)
>>> +		 * A -> USB RX
>>> +		 * B -> USB TX
>>> +		 * C -> DP1
>>> +		 * D -> DP0
>>> +		 * Flipped Orientation (CC2)
>>> +		 * A -> DP0
>>> +		 * B -> DP1
>>> +		 * C -> USB TX
>>> +		 * D -> USB RX
>>> +		 */
>>> +
>>> +		/* USB 3.1 Gen 1 and 2-lane DP */
>>> +		ctrl1_val |= PTN36502_MODE_CTRL1_MODE_USB_DP;
>>> +		link_ctrl_val |= PTN36502_DP_LINK_CTRL_LANES_2;
>>> +		break;
>>> +
>>> +	default:
>>> +		return -EOPNOTSUPP;
>>> +	}
>>> +
>>> +	/* Enable AUX monitoring */
>>> +	regmap_write(ptn->regmap, PTN36502_DEVICE_CTRL_REG,
>>> +		     PTN36502_DEVICE_CTRL_AUX_MONITORING_EN);
>>> +
>>> +	/* Enable AUX switch path */
>>> +	ctrl1_val |= PTN36502_MODE_CTRL1_AUX_CROSSBAR_SW_ON;
>>> +	if (reverse)
>>> +		ctrl1_val |= PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE;
>>> +	regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG, ctrl1_val);
>>> +
>>> +	/* DP Link rate: 5.4 Gbps (HBR2) */
>>> +	link_ctrl_val |= PTN36502_DP_LINK_CTRL_LINK_RATE_5_4GBPS;
>>> +	regmap_write(ptn->regmap, PTN36502_DP_LINK_CTRL_REG, link_ctrl_val);
>>> +
>>> +	/*
>>> +	 * For all lanes:
>>> +	 * - Rx equivalization gain: 3 dB
>>> +	 * - TX output swing control: 800 mVppd
>>> +	 * - Pre-emphasis control: 3.5 dB
>>> +	 */
>>> +	lane_ctrl_val = PTN36502_DP_LANE_CTRL_RX_GAIN_3DB |
>>> +			PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD |
>>> +			PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_3_5DB;
>>> +	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(0), lane_ctrl_val);
>>> +	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(1), lane_ctrl_val);
>>> +	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(2), lane_ctrl_val);
>>> +	regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(3), lane_ctrl_val);
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int ptn36502_sw_set(struct typec_switch_dev *sw, enum typec_orientation orientation)
>>> +{
>>> +	struct ptn36502 *ptn = typec_switch_get_drvdata(sw);
>>> +	int ret;
>>> +
>>> +	ret = typec_switch_set(ptn->typec_switch, orientation);
>>> +	if (ret)
>>> +		return ret;
>>> +
>>> +	mutex_lock(&ptn->lock);
>>> +
>>> +	if (ptn->orientation != orientation) {
>>> +		ptn->orientation = orientation;
>>> +
>>> +		ret = ptn36502_set(ptn);
>>> +	}
>>> +
>>> +	mutex_unlock(&ptn->lock);
>>> +
>>> +	return ret;
>>> +}
>>> +
>>> +static int ptn36502_retimer_set(struct typec_retimer *retimer, struct typec_retimer_state *state)
>>> +{
>>> +	struct ptn36502 *ptn = typec_retimer_get_drvdata(retimer);
>>> +	int ret = 0;
>>> +
>>> +	mutex_lock(&ptn->lock);
>>> +
>>> +	if (ptn->mode != state->mode) {
>>> +		ptn->mode = state->mode;
>>> +
>>> +		if (state->alt)
>>> +			ptn->svid = state->alt->svid;
>>> +		else
>>> +			ptn->svid = 0; // No SVID
>>> +
>>> +		ret = ptn36502_set(ptn);
>>> +	}
>>> +
>>> +	mutex_unlock(&ptn->lock);
>>> +
>>> +	return ret;
>>> +}
>>> +
>>> +static int ptn36502_detect(struct ptn36502 *ptn)
>>> +{
>>> +	struct device *dev = &ptn->client->dev;
>>> +	unsigned int reg_val;
>>> +	int ret;
>>> +
>>> +	ret = regmap_read(ptn->regmap, PTN36502_CHIP_ID_REG,
>>> +			  &reg_val);
>>> +	if (ret < 0)
>>> +		return dev_err_probe(dev, ret, "Failed to read chip ID\n");
>>> +
>>> +	if (reg_val != PTN36502_CHIP_ID)
>>> +		return dev_err_probe(dev, -ENODEV, "Unexpected chip ID: %x\n", reg_val);
>>> +
>>> +	ret = regmap_read(ptn->regmap, PTN36502_CHIP_REVISION_REG,
>>> +			  &reg_val);
>>> +	if (ret < 0)
>>> +		return dev_err_probe(dev, ret, "Failed to read chip revision\n");
>>> +
>>> +	dev_dbg(dev, "Chip revision: base layer version %lx, metal layer version %lx\n",
>>> +		PTN36502_CHIP_REVISION_BASE(reg_val),
>>> +		PTN36502_CHIP_REVISION_METAL(reg_val));
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +#if IS_ENABLED(CONFIG_OF) && IS_ENABLED(CONFIG_DRM_PANEL_BRIDGE)
>>> +static int ptn36502_bridge_attach(struct drm_bridge *bridge,
>>> +				    enum drm_bridge_attach_flags flags)
>>
>> I applied this patch and realised that that's not correctly aligned.
>> There are couple of extra spaces.
>>
>>> +{
>>> +	struct ptn36502 *ptn = container_of(bridge, struct ptn36502, bridge);
>>> +	struct drm_bridge *next_bridge;
>>> +
>>> +	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
>>> +		return -EINVAL;
>>> +
>>> +	next_bridge = devm_drm_of_get_bridge(&ptn->client->dev, ptn->client->dev.of_node, 0, 0);
>>> +	if (IS_ERR(next_bridge)) {
>>> +		dev_err(&ptn->client->dev, "failed to acquire drm_bridge: %pe\n", next_bridge);
>>> +		return PTR_ERR(next_bridge);
>>> +	}
>>> +
>>> +	return drm_bridge_attach(bridge->encoder, next_bridge, bridge,
>>> +				 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
>>> +}
>>> +
>>> +static const struct drm_bridge_funcs ptn36502_bridge_funcs = {
>>> +	.attach	= ptn36502_bridge_attach,
>>> +};
>>> +
>>> +static int ptn36502_register_bridge(struct ptn36502 *ptn)
>>> +{
>>> +	ptn->bridge.funcs = &ptn36502_bridge_funcs;
>>> +	ptn->bridge.of_node = ptn->client->dev.of_node;
>>> +
>>> +	return devm_drm_bridge_add(&ptn->client->dev, &ptn->bridge);
>>> +}
>>> +#else
>>> +static int ptn36502_register_bridge(struct ptn36502 *ptn)
>>> +{
>>> +	return 0;
>>> +}
>>> +#endif
>>> +
>>> +static const struct regmap_config ptn36502_regmap = {
>>> +	.max_register = 0x0d,
>>> +	.reg_bits = 8,
>>> +	.val_bits = 8,
>>> +};
>>> +
>>> +static int ptn36502_probe(struct i2c_client *client)
>>> +{
>>> +	struct device *dev = &client->dev;
>>> +	struct typec_switch_desc sw_desc = { };
>>> +	struct typec_retimer_desc retimer_desc = { };
>>> +	struct ptn36502 *ptn;
>>> +	int ret;
>>> +
>>> +	ptn = devm_kzalloc(dev, sizeof(*ptn), GFP_KERNEL);
>>> +	if (!ptn)
>>> +		return -ENOMEM;
>>> +
>>> +	ptn->client = client;
>>> +
>>> +	ptn->regmap = devm_regmap_init_i2c(client, &ptn36502_regmap);
>>> +	if (IS_ERR(ptn->regmap)) {
>>> +		dev_err(&client->dev, "Failed to allocate register map\n");
>>> +		return PTR_ERR(ptn->regmap);
>>> +	}
>>> +
>>> +	ptn->mode = TYPEC_STATE_SAFE;
>>> +	ptn->orientation = TYPEC_ORIENTATION_NONE;
>>> +
>>> +	mutex_init(&ptn->lock);
>>> +
>>> +	ptn->vdd18_supply = devm_regulator_get_optional(dev, "vdd18");
>>> +	if (IS_ERR(ptn->vdd18_supply))
>>> +		return PTR_ERR(ptn->vdd18_supply);
>>> +
>>> +	ptn->typec_switch = fwnode_typec_switch_get(dev->fwnode);
>>> +	if (IS_ERR(ptn->typec_switch))
>>> +		return dev_err_probe(dev, PTR_ERR(ptn->typec_switch),
>>> +				     "Failed to acquire orientation-switch\n");
>>> +
>>> +	ret = regulator_enable(ptn->vdd18_supply);
>>> +	if (ret)
>>> +		return dev_err_probe(dev, ret, "Failed to enable vdd18\n");
>>> +
>>> +	ret = ptn36502_detect(ptn);
>>> +	if (ret)
>>> +		goto err_disable_regulator;
>>> +
>>> +	ret = ptn36502_register_bridge(ptn);
>>> +	if (ret)
>>> +		goto err_disable_regulator;
>>> +
>>> +	sw_desc.drvdata = ptn;
>>> +	sw_desc.fwnode = dev->fwnode;
>>> +	sw_desc.set = ptn36502_sw_set;
>>> +
>>> +	ptn->sw = typec_switch_register(dev, &sw_desc);
>>> +	if (IS_ERR(ptn->sw)) {
>>> +		ret = dev_err_probe(dev, PTR_ERR(ptn->sw),
>>> +				    "Failed to register typec switch\n");
>>> +		goto err_disable_regulator;
>>> +	}
>>> +
>>> +	retimer_desc.drvdata = ptn;
>>> +	retimer_desc.fwnode = dev->fwnode;
>>> +	retimer_desc.set = ptn36502_retimer_set;
>>> +
>>> +	ptn->retimer = typec_retimer_register(dev, &retimer_desc);
>>> +	if (IS_ERR(ptn->retimer)) {
>>> +		ret = dev_err_probe(dev, PTR_ERR(ptn->retimer),
>>> +				    "Failed to register typec retimer\n");
>>> +		goto err_switch_unregister;
>>> +	}
>>> +
>>> +	return 0;
>>> +
>>> +err_switch_unregister:
>>> +	typec_switch_unregister(ptn->sw);
>>> +
>>> +err_disable_regulator:
>>> +	regulator_disable(ptn->vdd18_supply);
>>> +
>>> +	return ret;
>>> +}
>>> +
>>> +static void ptn36502_remove(struct i2c_client *client)
>>> +{
>>> +	struct ptn36502 *ptn = i2c_get_clientdata(client);
>>> +
>>> +	typec_retimer_unregister(ptn->retimer);
>>> +	typec_switch_unregister(ptn->sw);
>>> +
>>> +	regulator_disable(ptn->vdd18_supply);
>>> +}
>>> +
>>> +static const struct i2c_device_id ptn36502_table[] = {
>>> +	{ "ptn36502" },
>>> +	{ }
>>> +};
>>> +MODULE_DEVICE_TABLE(i2c, ptn36502_table);
>>> +
>>> +static const struct of_device_id ptn36502_of_table[] = {
>>> +	{ .compatible = "nxp,ptn36502" },
>>> +	{ }
>>> +};
>>> +MODULE_DEVICE_TABLE(of, ptn36502_of_table);
>>> +
>>> +static struct i2c_driver ptn36502_driver = {
>>> +	.driver = {
>>> +		.name = "ptn36502",
>>> +		.of_match_table = ptn36502_of_table,
>>> +	},
>>> +	.probe		= ptn36502_probe,
>>> +	.remove		= ptn36502_remove,
>>> +	.id_table	= ptn36502_table,
>>> +};
>>> +module_i2c_driver(ptn36502_driver);
>>> +
>>> +MODULE_AUTHOR("Luca Weiss <luca.weiss@fairphone.com>");
>>> +MODULE_DESCRIPTION("NXP PTN36502 Type-C driver");
>>> +MODULE_LICENSE("GPL");
>>
>> thanks,
> 

Re: [PATCH 2/2] usb: typec: add support for PTN36502 redriver

[Luca Weiss]

On Fri Oct 20, 2023 at 9:18 AM CEST, Neil Armstrong wrote:
> On 20/10/2023 08:13, Luca Weiss wrote:
> > On Tue Oct 17, 2023 at 10:34 AM CEST, Heikki Krogerus wrote:
> >> Hi,
> >>
> >> On Fri, Oct 13, 2023 at 04:24:48PM +0200, Luca Weiss wrote:
> >>> Add a driver for the NXP PTN36502 Type-C USB 3.1 Gen 1 and DisplayPort
> >>> v1.2 combo redriver.
> >>>
> >>> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
> >>
> >> Looks OK to me, but couple of nitpicks below. With those fixed:
> >>
> >> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> >>
> >>> ---
> >>>   drivers/usb/typec/mux/Kconfig    |  10 +
> >>>   drivers/usb/typec/mux/Makefile   |   1 +
> >>>   drivers/usb/typec/mux/ptn36502.c | 421 +++++++++++++++++++++++++++++++++++++++
> >>>   3 files changed, 432 insertions(+)
> >>>

[snip]

> >>> +#define PTN36502_CHIP_ID_REG				0x00
> >>> +#define PTN36502_CHIP_ID				0x02
> >>> +
> >>> +#define PTN36502_CHIP_REVISION_REG			0x01
> >>> +#define PTN36502_CHIP_REVISION_BASE(val)		FIELD_GET(GENMASK(7, 4), (val))
> >>> +#define PTN36502_CHIP_REVISION_METAL(val)		FIELD_GET(GENMASK(3, 0), (val))
> >>> +
> >>> +#define PTN36502_DP_LINK_CTRL_REG			0x06
> >>> +#define PTN36502_DP_LINK_CTRL_LANES_2			(2 << 2)
> >>> +#define PTN36502_DP_LINK_CTRL_LANES_4			(3 << 2)
> >>> +#define PTN36502_DP_LINK_CTRL_LINK_RATE_5_4GBPS		(2 << 0)
> >>> +
> >>> +/* Registers for lane 0 (0x07) to lane 3 (0x0a) have the same layout */
> >>> +#define PTN36502_DP_LANE_CTRL_REG(n)			(0x07 + (n))
> >>> +#define PTN36502_DP_LANE_CTRL_RX_GAIN_3DB		(2<<4)
> >>> +#define PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD		(2<<2)
> >>> +#define PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_3_5DB	(1<<0)
> >>> +
> >>> +#define PTN36502_MODE_CTRL1_REG				0x0b
> >>> +#define PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE		(1<<5)
> >>> +#define PTN36502_MODE_CTRL1_AUX_CROSSBAR_SW_ON		(1<<3)
> >>> +#define PTN36502_MODE_CTRL1_MODE_OFF			(0<<0)
> >>> +#define PTN36502_MODE_CTRL1_MODE_USB_ONLY		(1<<0)
> >>> +#define PTN36502_MODE_CTRL1_MODE_USB_DP			(2<<0)
> >>> +#define PTN36502_MODE_CTRL1_MODE_DP			(3<<0)
> >>> +
> >>> +#define PTN36502_DEVICE_CTRL_REG			0x0d
> >>> +#define PTN36502_DEVICE_CTRL_AUX_MONITORING_EN		(1<<7)
> >>
> >> You have couple of different styles here. Please try to always use
> >> BIT() and GENMASK() macros when possible. At the very least put spaces
> >> around << and >>.
> > 
> > Hi Heikki,
> > 
> > I was wondering when writing that whether GENMASK was actually proper
> > use for values you write to registers, when not actually used as a
> > bitmask.
> > 
> > Since the datasheet refers to e.g. with TX_SWING_800MVPPD (2<<2) that
> > you write a '2' to the correct bits of this register. But when using
> > BIT(3) kind of hides this relationship if someone refers back to the
> > datasheet. Or same with "3<<2" -> GENMASK(3, 2) or whatever.
>
> The proper way is to define the MASK for the field GENMASK(3, 2) and then
> use FIELD_PREP(GENMASK(3, 2), 2) to write 2 in this field.
>
> You could replace with:
> #define PTN36502_DP_LANE_CTRL_TX_SWING_MASK		GENMASK(3, 2)
> #define PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD		(2)
>
> and in the code
> lane_ctrl_val = FIELD_PREP(PTN36502_DP_LANE_CTRL_RX_GAIN_MASK,
> 			   PTN36502_DP_LANE_CTRL_RX_GAIN_3DB) |
> 		FIELD_PREP(PTN36502_DP_LANE_CTRL_TX_SWING_MASK,
> 			   PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD) |
> 		FIELD_PREP(PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_MASK,
> 			   PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_3_5DB);
>
> It's a little more verbose but it's much clearer and defines stuff correctly,
> no confusion possible.

Thanks for the advise, I'll update for v2!

Regards
Luca