Add driver support for ESWIN EIC7700 SoC USB controller

From: Hang Cao <[email protected]>

Add support for ESWIN EIC7700 USB driver controller.

Changes in v8->v7:
- Updates: dwc3-generic-plat.c
- Update commit message with acked-by.
- Fix build error in in probe function.
- Link to V7:https://lore.kernel.org/all/[email protected]/

Changes in v7->v6:
- Updates: dwc3-generic-plat.c
- Rename dwc3_plat_config to dwc3_generic_config.
- Refine the error message in probe function.
- Link to V6:https://lore.kernel.org/all/[email protected]/

Changes in v6->v5:
- Updates: dwc3-generic-plat.c
- Update commit message.
- Add dwc3_plat_config structure.
- Add dwc3_eic7700_init function.
- Link to V5:https://lore.kernel.org/all/[email protected]/

Changes in v5->v4:
- Updates: eswin,eic7700-usb.yaml
- Remove the unnecessary properties of quirk.

- Updates: dwc3-generic-plat.c
- Rebase to usb-testing branch of gregkh/usb.git.
- Removed .data
- Link to V4:https://lore.kernel.org/all/[email protected]/
- Link to gregkh/usb.git:https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git/tree/?h=usb-next

Changes in v4->v3:
- Updates:
- Removed config option patch dependency from cover letter, because the patch was applied.
- Remove dwc3-eic7700.c instead of dwc3-generic-plat.c.

- Updates: eswin,eic7700-usb.yaml
- Add usb_en clock.
- Add usb_rst reset.
- Update eswin,hsp-sp-csr description.
- Remove the last two unused items of eswin,hsp-sp-csr.

- Updates: dwc3-generic-plat.c
- Add eswin,eic7700-dwc3 to the compatible table.
- Add the dwc3_generic_match_data structure.
- Add the eic7700_dwc3_bus_init function to initialize the bus.
- Add the init_ops callback in the probe function.
- Link to V3: https://lore.kernel.org/all/[email protected]/

Changes in v3->v2:
- Updates: eswin,eic7700-usb.yaml
- Sort the attributes according to the DTS coding style.
- Remove the #address-cells and #size-cells attributes.
- Fold the child node into the parent.
- Update commit message.

- Updates: dwc3-eic7700.c
- Use dwc3 core as a library.
- Add system and runtime pm.
- Use pm_ptr and remove the __maybe_unused tags.
- Add new author name
- Add prepare and complete function
- Update commit message.
- Link to V2: https://lore.kernel.org/lkml/[email protected]/

Changes in v2->v1:
- Updates: eswin,eic7700-usb.yaml
- Drop the redundant descriptions.
- Supplement the constraints of resets.
- Replace "eswin,hsp_sp_csr" with "eswin,hsp-sp-csr" and add items description.
- Drop numa-node-id, This is not necessary.
- Add patternProperties and match the rules defined in the "snps,dwc3.yaml" file.
- Add "#address-cells" "#size-cells".
- Update the space indentation, remove the redundant labels, and sort the attributes according to the DTS encoding style.
- Drop the "status = "disabled" attribute.
- Update the common usb node names and fold the child nodes into the parent nodes.
- The warning detected by the robot has been resolved.

- Updates: dwc3-eic7700.c
- Remove dwc3_mode_show dwc3_mode_store dwc3_eswin_get_extcon_dev, dwc3_eswin_device_notifier and dwc3_eswin_host_notifier, usb role
detection and switching are not supported.
- Remove the hub-rst attribute, remove the dwc3_hub_rst_show and dwc3_hub_rst_store functions, this feature is not supported.
- Use syscon_regmap_lookup_by_phandle_args instead of the syscon_regmap_lookup_by_phandle function.
- Use dev_err_probe in probe function.
- Drop mutex_lock, which is not required.
- Remove clk_prepare_enable and of_clk_get, and manage multiple
clocks using devm_clk_bulk_get_all_enabled.
- Remove the device_init_wakeup related functions, which were
used incorrectly.
- Remove MODULE_ALIAS, which is used incorrectly.
- The warning detected by the robot has been resolved.
- Link to V1: https://lore.kernel.org/lkml/[email protected]/

Hang Cao (2):
dt-bindings: usb: Add ESWIN EIC7700 USB controller
usb: dwc3: eic7700: Add EIC7700 USB driver

 .../bindings/usb/eswin,eic7700-usb.yaml       | 94 +++++++++++++++++++
 drivers/usb/dwc3/dwc3-generic-plat.c          | 71 ++++++++++++--
 2 files changed, 158 insertions(+), 7 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/usb/eswin,eic7700-usb.yaml

--
2.34.1

From: Hang Cao <[email protected]>

Add Device Tree binding documentation for the ESWIN EIC7700 usb controller module.

---
 .../bindings/usb/eswin,eic7700-usb.yaml       | 94 +++++++++++++++++++
 1 file changed, 94 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/usb/eswin,eic7700-usb.yaml

new file mode 100644
index 000000000000..41c3b1b98991
@@ -0,0 +1,94 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/usb/eswin,eic7700-usb.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ESWIN EIC7700 SoC Usb Controller
+
+maintainers:
+  - Wei Yang <[email protected]>
+  - Senchuan Zhang <[email protected]>
+  - Hang Cao <[email protected]>
+
+description:
+  The Usb controller on EIC7700 SoC.
+
+allOf:
+  - $ref: snps,dwc3-common.yaml#
+
+properties:
+  compatible:
+    const: eswin,eic7700-dwc3
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  interrupt-names:
+    items:
+      - const: peripheral
+
+  clocks:
+    maxItems: 3
+
+  clock-names:
+    items:
+      - const: aclk
+      - const: cfg
+      - const: usb_en
+
+  resets:
+    maxItems: 2
+
+  reset-names:
+    items:
+      - const: vaux
+      - const: usb_rst
+
+  eswin,hsp-sp-csr:
+    description:
+      HSP CSR is to control and get status of different high-speed peripherals
+      (such as Ethernet, USB, SATA, etc.) via register, which can tune
+      board-level's parameters of PHY, etc.
+    $ref: /schemas/types.yaml#/definitions/phandle-array
+    items:
+      - items:
+          - description: phandle to HSP Register Controller hsp_sp_csr node.
+          - description: USB bus register offset.
+          - description: AXI low power register offset.
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - interrupts
+  - interrupt-names
+  - resets
+  - reset-names
+  - eswin,hsp-sp-csr
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    usb@50480000 {
+        compatible = "eswin,eic7700-dwc3";
+        reg = <0x50480000 0x10000>;
+        clocks = <&clock 135>,
+                 <&clock 136>,
+                 <&hspcrg 18>;
+        clock-names = "aclk", "cfg", "usb_en";
+        interrupt-parent = <&plic>;
+        interrupts = <85>;
+        interrupt-names = "peripheral";
+        resets = <&reset 84>, <&hspcrg 2>;
+        reset-names = "vaux", "usb_rst";
+        dr_mode = "peripheral";
+        maximum-speed = "high-speed";
+        phy_type = "utmi";
+        eswin,hsp-sp-csr = <&hsp_sp_csr 0x800 0x818>;
+    };

2.34.1

From: Hang Cao <[email protected]>

The EIC7700 instantiates two USB 3.0 DWC3 IPs, each of which is backward compatible with USB interfaces. It supports Super-speed (5Gb/s), DRD mode, and compatible with xHCI 1.1, etc. Each of instances supports 16 endpoints in device's mode and max 64 devices in host's mode.

This module needs to interact with the NOC via the AXI master bus, thus requiring some HSP configuration operations to achieve this. Ops include bus filter, pm signal or status to usb bus and so on.

---
 drivers/usb/dwc3/dwc3-generic-plat.c | 71 +++++++++++++++++++++++++---
 1 file changed, 64 insertions(+), 7 deletions(-)

index e869c7de7bc8..e846844e0023 100644
@@ -10,8 +10,16 @@
 #include <linux/clk.h>
 #include <linux/platform_device.h>
 #include <linux/reset.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
 #include "glue.h"
 
+#define EIC7700_HSP_BUS_FILTER_EN	BIT(0)
+#define EIC7700_HSP_BUS_CLKEN_GM	BIT(9)
+#define EIC7700_HSP_BUS_CLKEN_GS	BIT(16)
+#define EIC7700_HSP_AXI_LP_XM_CSYSREQ	BIT(0)
+#define EIC7700_HSP_AXI_LP_XS_CSYSREQ	BIT(16)
+
 struct dwc3_generic {
 	struct device		*dev;
 	struct dwc3		dwc;

@@ -20,6 +28,11 @@ struct dwc3_generic {
 	struct reset_control	*resets;
 };
 
+struct dwc3_generic_config {
+	int (*init)(struct dwc3_generic *dwc3g);
+	struct dwc3_properties properties;
+};
+
 #define to_dwc3_generic(d) container_of((d), struct dwc3_generic, dwc)
 
 static void dwc3_generic_reset_control_assert(void *data)

@@ -27,9 +40,38 @@ static void dwc3_generic_reset_control_assert(void *data)
 	reset_control_assert(data);
 }
 
+static int dwc3_eic7700_init(struct dwc3_generic *dwc3g)
+{
+	struct device *dev = dwc3g->dev;
+	struct regmap *regmap;
+	u32 hsp_usb_axi_lp;
+	u32 hsp_usb_bus;
+	u32 args[2];
+	u32 val;
+
+	regmap = syscon_regmap_lookup_by_phandle_args(dev->of_node,
+						      "eswin,hsp-sp-csr",
+						      ARRAY_SIZE(args), args);
+	if (IS_ERR(regmap)) {
+		dev_err(dev, "No hsp-sp-csr phandle specified\n");
+		return PTR_ERR(regmap);
+	}
+
+	hsp_usb_bus       = args[0];
+	hsp_usb_axi_lp    = args[1];
+
+	regmap_read(regmap, hsp_usb_bus, &val);
+	regmap_write(regmap, hsp_usb_bus, val | EIC7700_HSP_BUS_FILTER_EN |
+		     EIC7700_HSP_BUS_CLKEN_GM | EIC7700_HSP_BUS_CLKEN_GS);
+
+	regmap_write(regmap, hsp_usb_axi_lp, EIC7700_HSP_AXI_LP_XM_CSYSREQ |
+		     EIC7700_HSP_AXI_LP_XS_CSYSREQ);
+	return 0;
+}
+
 static int dwc3_generic_probe(struct platform_device *pdev)
 {
-	const struct dwc3_properties *properties;
+	const struct dwc3_generic_config *plat_config;
 	struct dwc3_probe_data probe_data = {};
 	struct device *dev = &pdev->dev;
 	struct dwc3_generic *dwc3g;

@@ -77,12 +119,21 @@ static int dwc3_generic_probe(struct platform_device *pdev)
 	probe_data.res = res;
 	probe_data.ignore_clocks_and_resets = true;
 
-	properties = of_device_get_match_data(dev);
-	if (properties)
-		probe_data.properties = *properties;
-	else
+	plat_config = of_device_get_match_data(dev);
+	if (!plat_config) {
 		probe_data.properties = DWC3_DEFAULT_PROPERTIES;
+		goto core_probe;
+	}
 
+	probe_data.properties = plat_config->properties;
+	if (plat_config->init) {
+		ret = plat_config->init(dwc3g);
+		if (ret)
+			return dev_err_probe(dev, ret,
+					     "failed to init platform\n");
+	}
+
+core_probe:
 	ret = dwc3_core_probe(&probe_data);
 	if (ret)
 		return dev_err_probe(dev, ret, "failed to register DWC3 Core\n");

@@ -150,13 +201,19 @@ static const struct dev_pm_ops dwc3_generic_dev_pm_ops = {
 		       dwc3_generic_runtime_idle)
 };
 
-static const struct dwc3_properties fsl_ls1028_dwc3 = {
-	.gsbuscfg0_reqinfo = 0x2222,
+static const struct dwc3_generic_config fsl_ls1028_dwc3 = {
+	.properties.gsbuscfg0_reqinfo = 0x2222,
+};
+
+static const struct dwc3_generic_config eic7700_dwc3 =  {
+	.init = dwc3_eic7700_init,
+	.properties = DWC3_DEFAULT_PROPERTIES,
 };
 
 static const struct of_device_id dwc3_generic_of_match[] = {
 	{ .compatible = "spacemit,k1-dwc3", },
 	{ .compatible = "fsl,ls1028a-dwc3", &fsl_ls1028_dwc3},
+	{ .compatible = "eswin,eic7700-dwc3", &eic7700_dwc3},
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, dwc3_generic_of_match);

--
2.34.1