[PATCH v3 0/2] AM62: Add support for AM62 USB wrapper driver

[PATCH v3 0/2] AM62: Add support for AM62 USB wrapper driver

[Aswath Govindraju]

The following series of patches add support for AM62 USB wrapper driver
and its corresponding bindings.

changes since v2:
- Removed the implementation of detecting the role from the wrapper
  driver and moved the implementation to using linux,extcon-usb-gpio
  driver for role detection.
- Updated the binding documentation and example to reflect the same.

changes since v1:
- Fixed the error with dev_pm_ops uninitialization, in patch 2.
  This was reported by kernel test bot
- In patch 1, made correction in grammer of clocks property description
  and added maxItems in the interrupts property based on comments
  received from Roger
- In patch 1, corrected the title, fixed the description of
  ti,syscon-phy-pll-refclk, added pattern properties and child node
  in the example based on the comments from Krzysztof. 

Aswath Govindraju (2):
  dt-bindings: usb: Add documentation for AM62 USB Wrapper module
  drivers: usb: dwc3: Add AM62 USB wrapper driver

 .../devicetree/bindings/usb/ti,am62-usb.yaml  | 115 +++++
 drivers/usb/dwc3/Kconfig                      |   9 +
 drivers/usb/dwc3/Makefile                     |   1 +
 drivers/usb/dwc3/dwc3-am62.c                  | 446 ++++++++++++++++++
 4 files changed, 571 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/usb/ti,am62-usb.yaml
 create mode 100644 drivers/usb/dwc3/dwc3-am62.c

-- 
2.17.1

[PATCH v3 1/2] dt-bindings: usb: Add documentation for AM62 USB Wrapper module

[Aswath Govindraju]

Add bindings for the TI's AM62 wrapper module for the Synopsys USBSS-DRD
controller.

Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
---

changes since v2:
- Removed the implementation of detecting the role from the wrapper
  driver and moved the implementation to using linux,extcon-usb-gpio
  driver for role detection.
- Updated the binding documentation and example to reflect the same.

 .../devicetree/bindings/usb/ti,am62-usb.yaml  | 115 ++++++++++++++++++
 1 file changed, 115 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/usb/ti,am62-usb.yaml

diff --git a/Documentation/devicetree/bindings/usb/ti,am62-usb.yaml b/Documentation/devicetree/bindings/usb/ti,am62-usb.yaml
new file mode 100644
index 000000000000..59b5ccea5671
--- /dev/null
+++ b/Documentation/devicetree/bindings/usb/ti,am62-usb.yaml
@@ -0,0 +1,115 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/usb/ti,am62-usb.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: TI's AM62 wrapper module for the Synopsys USBSS-DRD controller
+
+maintainers:
+  - Aswath Govindraju <a-govindraju@ti.com>
+
+properties:
+  compatible:
+    const: ti,am62-usb
+
+  reg:
+    maxItems: 1
+
+  ranges: true
+
+  power-domains:
+    description:
+      PM domain provider node and an args specifier containing
+      the USB ISO device id value. See,
+      Documentation/devicetree/bindings/soc/ti/sci-pm-domain.yaml
+    maxItems: 1
+
+  clocks:
+    description: Clock phandle to usb2_refclk
+    maxItems: 1
+
+  clock-names:
+    items:
+      - const: ref
+
+  interrupts:
+    description:
+      interrupt line to be used for detecting changes in VBUS
+    maxItems: 1
+
+  ti,vbus-divider:
+    description:
+      Should be present if USB VBUS line is connected to the
+      VBUS pin of the SoC via a 1/3 voltage divider.
+    type: boolean
+
+  ti,syscon-phy-pll-refclk:
+    $ref: /schemas/types.yaml#/definitions/phandle-array
+    items:
+      - items:
+          - description: Phandle to the SYSCON entry
+          - description: USB phy control register offset within SYSCON
+    description:
+      Specifier for conveying frequency of ref clock input, for the
+      operation of USB2PHY.
+
+  '#address-cells':
+    const: 2
+
+  '#size-cells':
+    const: 2
+
+patternProperties:
+  "^usb@[0-9a-f]+$":
+    $ref: snps,dwc3.yaml#
+    description: Required child node
+
+required:
+  - compatible
+  - reg
+  - power-domains
+  - clocks
+  - clock-names
+  - interrupts
+  - ti,syscon-phy-pll-refclk
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/soc/ti,sci_pm_domain.h>
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/gpio/gpio.h>
+
+    extcon_usb1: extcon-usb1 {
+      id-gpios = <&main_gpio1 51 GPIO_ACTIVE_HIGH>;
+    };
+
+    bus {
+      #address-cells = <2>;
+      #size-cells = <2>;
+
+      usbss1: usb@f910000 {
+        compatible = "ti,am62-usb";
+        reg = <0x00 0x0f910000 0x00 0x800>;
+        interrupts = <GIC_SPI 234 IRQ_TYPE_LEVEL_HIGH>; /* MISC IRQ */
+        clocks = <&k3_clks 162 3>;
+        clock-names = "ref";
+        ti,syscon-phy-pll-refclk = <&wkup_conf 0x4018>;
+        power-domains = <&k3_pds 179 TI_SCI_PD_EXCLUSIVE>;
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        usb@31100000 {
+          compatible = "snps,dwc3";
+          reg =<0x00 0x31100000 0x00 0x50000>;
+          interrupts = <GIC_SPI 226 IRQ_TYPE_LEVEL_HIGH>, /* irq.0 */
+                       <GIC_SPI 226 IRQ_TYPE_LEVEL_HIGH>; /* irq.0 */
+          interrupt-names = "host", "peripheral";
+          maximum-speed = "high-speed";
+          extcon = <&extcon_usb1>;
+          dr_mode = "otg";
+        };
+      };
+    };
-- 
2.17.1

Re: [PATCH v3 1/2] dt-bindings: usb: Add documentation for AM62 USB Wrapper module

[Krzysztof Kozlowski]

On 06/04/2022 15:52, Aswath Govindraju wrote:
> Add bindings for the TI's AM62 wrapper module for the Synopsys USBSS-DRD
> controller.
> 
> Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
> ---
> 
> changes since v2:
> - Removed the implementation of detecting the role from the wrapper
>   driver and moved the implementation to using linux,extcon-usb-gpio
>   driver for role detection.
> - Updated the binding documentation and example to reflect the same.
> 
>  .../devicetree/bindings/usb/ti,am62-usb.yaml  | 115 ++++++++++++++++++
>  1 file changed, 115 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/usb/ti,am62-usb.yaml
> 

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


Best regards,
Krzysztof

Re: [PATCH v3 1/2] dt-bindings: usb: Add documentation for AM62 USB Wrapper module

[Roger Quadros]

On 06/04/2022 16:52, Aswath Govindraju wrote:
> Add bindings for the TI's AM62 wrapper module for the Synopsys USBSS-DRD
> controller.
> 
> Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
> ---

Reviewed-by: Roger Quadros <rogerq@kernel.org>

--
cheers,
-roger

[PATCH v3 2/2] drivers: usb: dwc3: Add AM62 USB wrapper driver

[Aswath Govindraju]

In AM62 SoC, the Designware Core USB3 IP is progammed to operate in USB2.0
only mode. Add driver for AM62 USB DWC3 Wrapper.

Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
---

changes since v2:
- Removed the implementation of detecting the role from the wrapper
  driver and moved the implementation to using linux,extcon-usb-gpio
  driver for role detection.
- Updated the binding documentation and example to reflect the same.


 drivers/usb/dwc3/Kconfig     |   9 +
 drivers/usb/dwc3/Makefile    |   1 +
 drivers/usb/dwc3/dwc3-am62.c | 446 +++++++++++++++++++++++++++++++++++
 3 files changed, 456 insertions(+)
 create mode 100644 drivers/usb/dwc3/dwc3-am62.c

diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
index c483f28b695d..cd9a734522a7 100644
--- a/drivers/usb/dwc3/Kconfig
+++ b/drivers/usb/dwc3/Kconfig
@@ -159,4 +159,13 @@ config USB_DWC3_XILINX
 	  This driver handles both ZynqMP and Versal SoC operations.
 	  Say 'Y' or 'M' if you have one such device.
 
+config USB_DWC3_AM62
+	tristate "Texas Instruments AM62 Platforms"
+	depends on ARCH_K3 || COMPILE_TEST
+	default USB_DWC3
+	help
+	  Support TI's AM62 platforms with DesignWare Core USB3 IP.
+	  The Designware Core USB3 IP is progammed to operate in
+	  in USB 2.0 mode only.
+	  Say 'Y' or 'M' here if you have one such device
 endif
diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
index 2d499de6f66a..9f66bd82b639 100644
--- a/drivers/usb/dwc3/Makefile
+++ b/drivers/usb/dwc3/Makefile
@@ -42,6 +42,7 @@ endif
 # and allyesconfig builds.
 ##
 
+obj-$(CONFIG_USB_DWC3_AM62)		+= dwc3-am62.o
 obj-$(CONFIG_USB_DWC3_OMAP)		+= dwc3-omap.o
 obj-$(CONFIG_USB_DWC3_EXYNOS)		+= dwc3-exynos.o
 obj-$(CONFIG_USB_DWC3_PCI)		+= dwc3-pci.o
diff --git a/drivers/usb/dwc3/dwc3-am62.c b/drivers/usb/dwc3/dwc3-am62.c
new file mode 100644
index 000000000000..5700258c8deb
--- /dev/null
+++ b/drivers/usb/dwc3/dwc3-am62.c
@@ -0,0 +1,446 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * dwc3-am62.c - TI specific Glue layer for AM62 DWC3 USB Controller
+ *
+ * Copyright (C) 2022 Texas Instruments Incorporated - https://www.ti.com
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/workqueue.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/clk.h>
+#include <linux/regmap.h>
+#include <linux/devm-helpers.h>
+#include <linux/pinctrl/consumer.h>
+
+/* USB WRAPPER register offsets */
+#define USBSS_PID			0x0
+#define USBSS_OVERCURRENT_CTRL		0x4
+#define USBSS_PHY_CONFIG		0x8
+#define USBSS_PHY_TEST			0xc
+#define USBSS_CORE_STAT			0x14
+#define USBSS_HOST_VBUS_CTRL		0x18
+#define USBSS_MODE_CONTROL		0x1c
+#define USBSS_WAKEUP_CONFIG		0x30
+#define USBSS_WAKEUP_STAT		0x34
+#define USBSS_OVERRIDE_CONFIG		0x38
+#define USBSS_IRQ_MISC_STATUS_RAW	0x430
+#define USBSS_IRQ_MISC_STATUS		0x434
+#define USBSS_IRQ_MISC_ENABLE_SET	0x438
+#define USBSS_IRQ_MISC_ENABLE_CLR	0x43c
+#define USBSS_IRQ_MISC_EOI		0x440
+#define USBSS_INTR_TEST			0x490
+#define USBSS_VBUS_FILTER		0x614
+#define USBSS_VBUS_STAT			0x618
+#define USBSS_DEBUG_CFG			0x708
+#define USBSS_DEBUG_DATA		0x70c
+#define USBSS_HOST_HUB_CTRL		0x714
+
+/* PHY CONFIG register bits */
+#define USBSS_PHY_VBUS_SEL_MASK		GENMASK(2, 1)
+#define USBSS_PHY_VBUS_SEL_SHIFT	1
+#define USBSS_PHY_LANE_REVERSE		BIT(0)
+
+/* MODE CONTROL register bits */
+#define USBSS_MODE_VALID	BIT(0)
+
+/* WAKEUP CONFIG register bits */
+#define USBSS_WAKEUP_CFG_OVERCURRENT_EN	BIT(3)
+#define USBSS_WAKEUP_CFG_LINESTATE_EN	BIT(2)
+#define USBSS_WAKEUP_CFG_SESSVALID_EN	BIT(1)
+#define USBSS_WAKEUP_CFG_VBUSVALID_EN	BIT(0)
+
+/* WAKEUP STAT register bits */
+#define USBSS_WAKEUP_STAT_OVERCURRENT	BIT(4)
+#define USBSS_WAKEUP_STAT_LINESTATE	BIT(3)
+#define USBSS_WAKEUP_STAT_SESSVALID	BIT(2)
+#define USBSS_WAKEUP_STAT_VBUSVALID	BIT(1)
+#define USBSS_WAKEUP_STAT_CLR		BIT(0)
+
+/* IRQ_MISC_STATUS_RAW register bits */
+#define USBSS_IRQ_MISC_RAW_VBUSVALID	BIT(22)
+#define USBSS_IRQ_MISC_RAW_SESSVALID	BIT(20)
+
+/* IRQ_MISC_STATUS register bits */
+#define USBSS_IRQ_MISC_VBUSVALID	BIT(22)
+#define USBSS_IRQ_MISC_SESSVALID	BIT(20)
+
+/* IRQ_MISC_ENABLE_SET register bits */
+#define USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID	BIT(22)
+#define USBSS_IRQ_MISC_ENABLE_SET_SESSVALID	BIT(20)
+
+/* IRQ_MISC_ENABLE_CLR register bits */
+#define USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID	BIT(22)
+#define USBSS_IRQ_MISC_ENABLE_CLR_SESSVALID	BIT(20)
+
+/* IRQ_MISC_EOI register bits */
+#define USBSS_IRQ_MISC_EOI_VECTOR	BIT(0)
+
+/* VBUS_STAT register bits */
+#define USBSS_VBUS_STAT_SESSVALID	BIT(2)
+#define USBSS_VBUS_STAT_VBUSVALID	BIT(0)
+
+/* Mask for PHY PLL REFCLK */
+#define PHY_PLL_REFCLK_MASK	GENMASK(3, 0)
+
+#define DWC3_AM62_AUTOSUSPEND_DELAY	100
+
+struct dwc3_data {
+	struct device *dev;
+	void __iomem *usbss;
+	struct clk *usb2_refclk;
+	struct work_struct work;
+	int vbus_irq;
+	int rate_code;
+	int connect;
+	struct regmap *syscon;
+	unsigned int offset;
+	unsigned int vbus_divider;
+};
+
+static const int dwc3_ti_rate_table[] = {	/* in KHZ */
+	9600,
+	10000,
+	12000,
+	19200,
+	20000,
+	24000,
+	25000,
+	26000,
+	38400,
+	40000,
+	58000,
+	50000,
+	52000,
+};
+
+static inline u32 dwc3_ti_readl(struct dwc3_data *data, u32 offset)
+{
+	return readl((data->usbss) + offset);
+}
+
+static inline void dwc3_ti_writel(struct dwc3_data *data, u32 offset, u32 value)
+{
+	writel(value, (data->usbss) + offset);
+}
+
+static void connect_detect_work(struct work_struct *work)
+{
+	struct dwc3_data *data =
+		container_of(work, struct dwc3_data, work);
+	u32 vbus_state, reg;
+	int connect = 0;
+
+	/* Read the status for VBUS valid register */
+	vbus_state = dwc3_ti_readl(data, USBSS_VBUS_STAT);
+	vbus_state &= USBSS_VBUS_STAT_VBUSVALID;
+
+	if (vbus_state)
+		connect = 1;
+
+	/* Set or clear mode valid bit based on connect or disconnect event */
+	if (data->connect != connect) {
+		reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
+		if (connect)
+			reg |= USBSS_MODE_VALID;
+		else
+			reg &= ~USBSS_MODE_VALID;
+
+		dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
+		data->connect = connect;
+	}
+}
+
+static irqreturn_t connect_detect_irq_handler(int irq, void *dev_id)
+{
+	struct dwc3_data *data = dev_id;
+	u32 reg;
+
+	/* Clear VBUS interrupt always to aviod queuing up redundant work items */
+	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_STATUS);
+	reg |= USBSS_IRQ_MISC_VBUSVALID;
+	dwc3_ti_writel(data, USBSS_IRQ_MISC_STATUS, reg);
+
+	queue_work(system_power_efficient_wq, &data->work);
+
+	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_EOI);
+	reg &= ~USBSS_IRQ_MISC_EOI_VECTOR;
+	dwc3_ti_writel(data, USBSS_IRQ_MISC_EOI, reg);
+	return IRQ_HANDLED;
+}
+
+static int dwc3_ti_vbus_irq_setup(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct dwc3_data *data = platform_get_drvdata(pdev);
+	int irq, ret;
+
+	/* Get the misc interrupt */
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	ret = devm_request_irq(dev, irq, connect_detect_irq_handler, IRQF_SHARED,
+			       dev_name(dev), data);
+	if (ret) {
+		dev_err(dev, "failed to required IRQ #%d-->%d\n",
+			irq, ret);
+		return ret;
+	}
+
+	data->vbus_irq = irq;
+
+	return 0;
+}
+
+static int phy_syscon_pll_refclk(struct dwc3_data *data)
+{
+	struct device *dev = data->dev;
+	struct device_node *node = dev->of_node;
+	struct of_phandle_args args;
+	struct regmap *syscon;
+	int ret;
+
+	syscon = syscon_regmap_lookup_by_phandle(node, "ti,syscon-phy-pll-refclk");
+	if (IS_ERR(syscon)) {
+		dev_err(dev, "unable to get ti,syscon-phy-pll-refclk regmap\n");
+		return PTR_ERR(syscon);
+	}
+
+	data->syscon = syscon;
+
+	ret = of_parse_phandle_with_fixed_args(node, "ti,syscon-phy-pll-refclk", 1,
+					       0, &args);
+	if (ret)
+		return ret;
+
+	data->offset = args.args[0];
+
+	ret = regmap_update_bits(data->syscon, data->offset, PHY_PLL_REFCLK_MASK, data->rate_code);
+	if (ret) {
+		dev_err(dev, "failed to set phy pll reference clock rate\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static void dwc3_ti_enable_irqs(struct dwc3_data *data)
+{
+	u32 reg;
+
+	/* enable VBUSVALID interrupt */
+	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_ENABLE_SET);
+	reg |= USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID;
+	dwc3_ti_writel(data, USBSS_IRQ_MISC_ENABLE_SET, reg);
+}
+
+static void dwc3_ti_disable_irqs(struct dwc3_data *data)
+{
+	u32 reg;
+
+	/* disable VBUSVALID interrupt */
+	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_ENABLE_CLR);
+	reg |= USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID;
+	dwc3_ti_writel(data, USBSS_IRQ_MISC_ENABLE_CLR, reg);
+}
+
+static int dwc3_ti_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *node = pdev->dev.of_node;
+	struct dwc3_data *data;
+	int i, ret;
+	unsigned long rate;
+	u32 reg;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->dev = dev;
+	platform_set_drvdata(pdev, data);
+
+	data->usbss = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(data->usbss)) {
+		dev_err(dev, "can't map IOMEM resource\n");
+		return PTR_ERR(data->usbss);
+	}
+
+	data->usb2_refclk = devm_clk_get(dev, "ref");
+	if (IS_ERR(data->usb2_refclk)) {
+		dev_err(dev, "can't get usb2_refclk\n");
+		return PTR_ERR(data->usb2_refclk);
+	}
+
+	/* Calculate the rate code */
+	rate = clk_get_rate(data->usb2_refclk);
+	rate /= 1000;	// To KHz
+	for (i = 0; i < ARRAY_SIZE(dwc3_ti_rate_table); i++) {
+		if (dwc3_ti_rate_table[i] == rate)
+			break;
+	}
+
+	if (i == ARRAY_SIZE(dwc3_ti_rate_table)) {
+		dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate);
+		ret = -EINVAL;
+		goto err_clk_disable;
+	}
+
+	data->rate_code = i;
+
+	/* Read the syscon property and set the rate code */
+	ret = phy_syscon_pll_refclk(data);
+	if (ret)
+		goto err_clk_disable;
+
+	/* VBUS divider select */
+	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
+	reg = dwc3_ti_readl(data, USBSS_PHY_CONFIG);
+	if (data->vbus_divider)
+		reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT;
+
+	dwc3_ti_writel(data, USBSS_PHY_CONFIG, reg);
+
+	/* Initialize a work queue */
+	ret = devm_work_autocancel(dev, &data->work, connect_detect_work);
+	if (ret)
+		goto err_clk_disable;
+
+	/* Read and set VBUS IRQ */
+	ret = dwc3_ti_vbus_irq_setup(pdev);
+	if (ret)
+		goto err_clk_disable;
+
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+	/*
+	 * Don't ignore its dependencies with its children
+	 */
+	pm_suspend_ignore_children(dev, false);
+	clk_prepare_enable(data->usb2_refclk);
+	pm_runtime_get_noresume(dev);
+
+	ret = of_platform_populate(node, NULL, NULL, dev);
+	if (ret) {
+		dev_err(dev, "failed to create dwc3 core: %d\n", ret);
+		goto err_pm_disable;
+	}
+
+	/* Enable vbus irq */
+	dwc3_ti_enable_irqs(data);
+
+	connect_detect_work(&data->work);
+
+	/* Setting up autosuspend */
+	pm_runtime_set_autosuspend_delay(dev, DWC3_AM62_AUTOSUSPEND_DELAY);
+	pm_runtime_use_autosuspend(dev);
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
+	return 0;
+
+err_pm_disable:
+	clk_disable_unprepare(data->usb2_refclk);
+	pm_runtime_disable(dev);
+	pm_runtime_set_suspended(dev);
+err_clk_disable:
+	clk_put(data->usb2_refclk);
+	return ret;
+}
+
+static int dwc3_ti_remove_core(struct device *dev, void *c)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+
+	platform_device_unregister(pdev);
+	return 0;
+}
+
+static int dwc3_ti_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct dwc3_data *data = platform_get_drvdata(pdev);
+	u32 reg;
+
+	dwc3_ti_disable_irqs(data);
+
+	device_for_each_child(dev, NULL, dwc3_ti_remove_core);
+
+	/* Clear mode valid bit */
+	reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
+	reg &= ~USBSS_MODE_VALID;
+	dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
+
+	pm_runtime_put_sync(dev);
+	clk_disable_unprepare(data->usb2_refclk);
+	pm_runtime_disable(dev);
+	pm_runtime_set_suspended(dev);
+
+	clk_put(data->usb2_refclk);
+	platform_set_drvdata(pdev, NULL);
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int dwc3_ti_suspend_common(struct device *dev)
+{
+	struct dwc3_data *data = dev_get_drvdata(dev);
+
+	/* disable irqs */
+	dwc3_ti_disable_irqs(data);
+
+	clk_disable_unprepare(data->usb2_refclk);
+
+	return 0;
+}
+
+static int dwc3_ti_resume_common(struct device *dev)
+{
+	struct dwc3_data *data = dev_get_drvdata(dev);
+
+	clk_prepare_enable(data->usb2_refclk);
+
+	/* Enable irqs */
+	dwc3_ti_enable_irqs(data);
+
+	return 0;
+}
+
+static UNIVERSAL_DEV_PM_OPS(dwc3_ti_pm_ops, dwc3_ti_suspend_common,
+			    dwc3_ti_resume_common, NULL);
+
+#define DEV_PM_OPS	(&dwc3_ti_pm_ops)
+#else
+#define DEV_PM_OPS	NULL
+#endif /* CONFIG_PM */
+
+static const struct of_device_id dwc3_ti_of_match[] = {
+	{ .compatible = "ti,am62-usb"},
+	{},
+};
+MODULE_DEVICE_TABLE(of, dwc3_ti_of_match);
+
+static struct platform_driver dwc3_ti_driver = {
+	.probe		= dwc3_ti_probe,
+	.remove		= dwc3_ti_remove,
+	.driver		= {
+		.name	= "dwc3-am62",
+		.pm	= DEV_PM_OPS,
+		.of_match_table = dwc3_ti_of_match,
+	},
+};
+
+module_platform_driver(dwc3_ti_driver);
+
+MODULE_ALIAS("platform:dwc3-am62");
+MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("DesignWare USB3 TI Glue Layer");
-- 
2.17.1

Re: [PATCH v3 2/2] drivers: usb: dwc3: Add AM62 USB wrapper driver

[Roger Quadros]

Hi Aswath,

On 06/04/2022 16:52, Aswath Govindraju wrote:
> In AM62 SoC, the Designware Core USB3 IP is progammed to operate in USB2.0
> only mode. Add driver for AM62 USB DWC3 Wrapper.
> 
> Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
> ---
> 
> changes since v2:
> - Removed the implementation of detecting the role from the wrapper
>   driver and moved the implementation to using linux,extcon-usb-gpio
>   driver for role detection.
> - Updated the binding documentation and example to reflect the same.
> 
> 
>  drivers/usb/dwc3/Kconfig     |   9 +
>  drivers/usb/dwc3/Makefile    |   1 +
>  drivers/usb/dwc3/dwc3-am62.c | 446 +++++++++++++++++++++++++++++++++++
>  3 files changed, 456 insertions(+)
>  create mode 100644 drivers/usb/dwc3/dwc3-am62.c
> 
> diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
> index c483f28b695d..cd9a734522a7 100644
> --- a/drivers/usb/dwc3/Kconfig
> +++ b/drivers/usb/dwc3/Kconfig
> @@ -159,4 +159,13 @@ config USB_DWC3_XILINX
>  	  This driver handles both ZynqMP and Versal SoC operations.
>  	  Say 'Y' or 'M' if you have one such device.
>  
> +config USB_DWC3_AM62
> +	tristate "Texas Instruments AM62 Platforms"
> +	depends on ARCH_K3 || COMPILE_TEST

Does this need to depend on EXTCON as well if COMPILE_TEST is not set?

> +	default USB_DWC3
> +	help
> +	  Support TI's AM62 platforms with DesignWare Core USB3 IP.
> +	  The Designware Core USB3 IP is progammed to operate in

typo 'programmed'

> +	  in USB 2.0 mode only.
> +	  Say 'Y' or 'M' here if you have one such device
>  endif
> diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
> index 2d499de6f66a..9f66bd82b639 100644
> --- a/drivers/usb/dwc3/Makefile
> +++ b/drivers/usb/dwc3/Makefile
> @@ -42,6 +42,7 @@ endif
>  # and allyesconfig builds.
>  ##
>  
> +obj-$(CONFIG_USB_DWC3_AM62)		+= dwc3-am62.o
>  obj-$(CONFIG_USB_DWC3_OMAP)		+= dwc3-omap.o
>  obj-$(CONFIG_USB_DWC3_EXYNOS)		+= dwc3-exynos.o
>  obj-$(CONFIG_USB_DWC3_PCI)		+= dwc3-pci.o
> diff --git a/drivers/usb/dwc3/dwc3-am62.c b/drivers/usb/dwc3/dwc3-am62.c
> new file mode 100644
> index 000000000000..5700258c8deb
> --- /dev/null
> +++ b/drivers/usb/dwc3/dwc3-am62.c
> @@ -0,0 +1,446 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * dwc3-am62.c - TI specific Glue layer for AM62 DWC3 USB Controller
> + *
> + * Copyright (C) 2022 Texas Instruments Incorporated - https://www.ti.com
> + */
> +
> +#include <linux/init.h>
> +#include <linux/interrupt.h>
> +#include <linux/irq.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/workqueue.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/clk.h>
> +#include <linux/regmap.h>
> +#include <linux/devm-helpers.h>
> +#include <linux/pinctrl/consumer.h>
> +
> +/* USB WRAPPER register offsets */
> +#define USBSS_PID			0x0
> +#define USBSS_OVERCURRENT_CTRL		0x4
> +#define USBSS_PHY_CONFIG		0x8
> +#define USBSS_PHY_TEST			0xc
> +#define USBSS_CORE_STAT			0x14
> +#define USBSS_HOST_VBUS_CTRL		0x18
> +#define USBSS_MODE_CONTROL		0x1c
> +#define USBSS_WAKEUP_CONFIG		0x30
> +#define USBSS_WAKEUP_STAT		0x34
> +#define USBSS_OVERRIDE_CONFIG		0x38
> +#define USBSS_IRQ_MISC_STATUS_RAW	0x430
> +#define USBSS_IRQ_MISC_STATUS		0x434
> +#define USBSS_IRQ_MISC_ENABLE_SET	0x438
> +#define USBSS_IRQ_MISC_ENABLE_CLR	0x43c
> +#define USBSS_IRQ_MISC_EOI		0x440
> +#define USBSS_INTR_TEST			0x490
> +#define USBSS_VBUS_FILTER		0x614
> +#define USBSS_VBUS_STAT			0x618
> +#define USBSS_DEBUG_CFG			0x708
> +#define USBSS_DEBUG_DATA		0x70c
> +#define USBSS_HOST_HUB_CTRL		0x714
> +
> +/* PHY CONFIG register bits */
> +#define USBSS_PHY_VBUS_SEL_MASK		GENMASK(2, 1)
> +#define USBSS_PHY_VBUS_SEL_SHIFT	1
> +#define USBSS_PHY_LANE_REVERSE		BIT(0)
> +
> +/* MODE CONTROL register bits */
> +#define USBSS_MODE_VALID	BIT(0)
> +
> +/* WAKEUP CONFIG register bits */
> +#define USBSS_WAKEUP_CFG_OVERCURRENT_EN	BIT(3)
> +#define USBSS_WAKEUP_CFG_LINESTATE_EN	BIT(2)
> +#define USBSS_WAKEUP_CFG_SESSVALID_EN	BIT(1)
> +#define USBSS_WAKEUP_CFG_VBUSVALID_EN	BIT(0)
> +
> +/* WAKEUP STAT register bits */
> +#define USBSS_WAKEUP_STAT_OVERCURRENT	BIT(4)
> +#define USBSS_WAKEUP_STAT_LINESTATE	BIT(3)
> +#define USBSS_WAKEUP_STAT_SESSVALID	BIT(2)
> +#define USBSS_WAKEUP_STAT_VBUSVALID	BIT(1)
> +#define USBSS_WAKEUP_STAT_CLR		BIT(0)
> +
> +/* IRQ_MISC_STATUS_RAW register bits */
> +#define USBSS_IRQ_MISC_RAW_VBUSVALID	BIT(22)
> +#define USBSS_IRQ_MISC_RAW_SESSVALID	BIT(20)
> +
> +/* IRQ_MISC_STATUS register bits */
> +#define USBSS_IRQ_MISC_VBUSVALID	BIT(22)
> +#define USBSS_IRQ_MISC_SESSVALID	BIT(20)
> +
> +/* IRQ_MISC_ENABLE_SET register bits */
> +#define USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID	BIT(22)
> +#define USBSS_IRQ_MISC_ENABLE_SET_SESSVALID	BIT(20)
> +
> +/* IRQ_MISC_ENABLE_CLR register bits */
> +#define USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID	BIT(22)
> +#define USBSS_IRQ_MISC_ENABLE_CLR_SESSVALID	BIT(20)
> +
> +/* IRQ_MISC_EOI register bits */
> +#define USBSS_IRQ_MISC_EOI_VECTOR	BIT(0)
> +
> +/* VBUS_STAT register bits */
> +#define USBSS_VBUS_STAT_SESSVALID	BIT(2)
> +#define USBSS_VBUS_STAT_VBUSVALID	BIT(0)
> +
> +/* Mask for PHY PLL REFCLK */
> +#define PHY_PLL_REFCLK_MASK	GENMASK(3, 0)
> +
> +#define DWC3_AM62_AUTOSUSPEND_DELAY	100
> +
> +struct dwc3_data {
> +	struct device *dev;
> +	void __iomem *usbss;
> +	struct clk *usb2_refclk;
> +	struct work_struct work;
> +	int vbus_irq;
> +	int rate_code;
> +	int connect;
> +	struct regmap *syscon;
> +	unsigned int offset;
> +	unsigned int vbus_divider;
> +};
> +
> +static const int dwc3_ti_rate_table[] = {	/* in KHZ */
> +	9600,
> +	10000,
> +	12000,
> +	19200,
> +	20000,
> +	24000,
> +	25000,
> +	26000,
> +	38400,
> +	40000,
> +	58000,
> +	50000,
> +	52000,
> +};
> +
> +static inline u32 dwc3_ti_readl(struct dwc3_data *data, u32 offset)
> +{
> +	return readl((data->usbss) + offset);
> +}
> +
> +static inline void dwc3_ti_writel(struct dwc3_data *data, u32 offset, u32 value)
> +{
> +	writel(value, (data->usbss) + offset);
> +}
> +
> +static void connect_detect_work(struct work_struct *work)
> +{
> +	struct dwc3_data *data =
> +		container_of(work, struct dwc3_data, work);
> +	u32 vbus_state, reg;
> +	int connect = 0;
> +
> +	/* Read the status for VBUS valid register */
> +	vbus_state = dwc3_ti_readl(data, USBSS_VBUS_STAT);
> +	vbus_state &= USBSS_VBUS_STAT_VBUSVALID;
> +
> +	if (vbus_state)
> +		connect = 1;
> +
> +	/* Set or clear mode valid bit based on connect or disconnect event */
> +	if (data->connect != connect) {
> +		reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
> +		if (connect)
> +			reg |= USBSS_MODE_VALID;
> +		else
> +			reg &= ~USBSS_MODE_VALID;
> +
> +		dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
> +		data->connect = connect;
> +	}
> +}
> +
> +static irqreturn_t connect_detect_irq_handler(int irq, void *dev_id)
> +{
> +	struct dwc3_data *data = dev_id;
> +	u32 reg;
> +
> +	/* Clear VBUS interrupt always to aviod queuing up redundant work items */
> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_STATUS);
> +	reg |= USBSS_IRQ_MISC_VBUSVALID;
> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_STATUS, reg);
> +
> +	queue_work(system_power_efficient_wq, &data->work);
> +
> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_EOI);
> +	reg &= ~USBSS_IRQ_MISC_EOI_VECTOR;
> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_EOI, reg);
> +	return IRQ_HANDLED;
> +}
> +
> +static int dwc3_ti_vbus_irq_setup(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct dwc3_data *data = platform_get_drvdata(pdev);
> +	int irq, ret;
> +
> +	/* Get the misc interrupt */
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0)
> +		return irq;
> +
> +	ret = devm_request_irq(dev, irq, connect_detect_irq_handler, IRQF_SHARED,
> +			       dev_name(dev), data);
> +	if (ret) {
> +		dev_err(dev, "failed to required IRQ #%d-->%d\n",
> +			irq, ret);
> +		return ret;
> +	}
> +
> +	data->vbus_irq = irq;
> +
> +	return 0;
> +}
> +
> +static int phy_syscon_pll_refclk(struct dwc3_data *data)
> +{
> +	struct device *dev = data->dev;
> +	struct device_node *node = dev->of_node;
> +	struct of_phandle_args args;
> +	struct regmap *syscon;
> +	int ret;
> +
> +	syscon = syscon_regmap_lookup_by_phandle(node, "ti,syscon-phy-pll-refclk");
> +	if (IS_ERR(syscon)) {
> +		dev_err(dev, "unable to get ti,syscon-phy-pll-refclk regmap\n");
> +		return PTR_ERR(syscon);
> +	}
> +
> +	data->syscon = syscon;
> +
> +	ret = of_parse_phandle_with_fixed_args(node, "ti,syscon-phy-pll-refclk", 1,
> +					       0, &args);
> +	if (ret)
> +		return ret;
> +
> +	data->offset = args.args[0];
> +
> +	ret = regmap_update_bits(data->syscon, data->offset, PHY_PLL_REFCLK_MASK, data->rate_code);
> +	if (ret) {
> +		dev_err(dev, "failed to set phy pll reference clock rate\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static void dwc3_ti_enable_irqs(struct dwc3_data *data)
> +{
> +	u32 reg;
> +
> +	/* enable VBUSVALID interrupt */
> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_ENABLE_SET);
> +	reg |= USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID;
> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_ENABLE_SET, reg);
> +}
> +
> +static void dwc3_ti_disable_irqs(struct dwc3_data *data)
> +{
> +	u32 reg;
> +
> +	/* disable VBUSVALID interrupt */
> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_ENABLE_CLR);
> +	reg |= USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID;
> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_ENABLE_CLR, reg);
> +}
> +
> +static int dwc3_ti_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct device_node *node = pdev->dev.of_node;
> +	struct dwc3_data *data;
> +	int i, ret;
> +	unsigned long rate;
> +	u32 reg;
> +
> +	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> +	if (!data)
> +		return -ENOMEM;
> +
> +	data->dev = dev;
> +	platform_set_drvdata(pdev, data);
> +
> +	data->usbss = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(data->usbss)) {
> +		dev_err(dev, "can't map IOMEM resource\n");
> +		return PTR_ERR(data->usbss);
> +	}
> +
> +	data->usb2_refclk = devm_clk_get(dev, "ref");
> +	if (IS_ERR(data->usb2_refclk)) {
> +		dev_err(dev, "can't get usb2_refclk\n");
> +		return PTR_ERR(data->usb2_refclk);
> +	}
> +
> +	/* Calculate the rate code */
> +	rate = clk_get_rate(data->usb2_refclk);
> +	rate /= 1000;	// To KHz
> +	for (i = 0; i < ARRAY_SIZE(dwc3_ti_rate_table); i++) {
> +		if (dwc3_ti_rate_table[i] == rate)
> +			break;
> +	}
> +
> +	if (i == ARRAY_SIZE(dwc3_ti_rate_table)) {
> +		dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate);
> +		ret = -EINVAL;
> +		goto err_clk_disable;
> +	}
> +
> +	data->rate_code = i;
> +
> +	/* Read the syscon property and set the rate code */
> +	ret = phy_syscon_pll_refclk(data);
> +	if (ret)
> +		goto err_clk_disable;
> +
> +	/* VBUS divider select */
> +	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
> +	reg = dwc3_ti_readl(data, USBSS_PHY_CONFIG);
> +	if (data->vbus_divider)
> +		reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT;
> +
> +	dwc3_ti_writel(data, USBSS_PHY_CONFIG, reg);
> +
> +	/* Initialize a work queue */
> +	ret = devm_work_autocancel(dev, &data->work, connect_detect_work);
> +	if (ret)
> +		goto err_clk_disable;
> +
> +	/* Read and set VBUS IRQ */
> +	ret = dwc3_ti_vbus_irq_setup(pdev);
> +	if (ret)
> +		goto err_clk_disable;
> +
> +	pm_runtime_set_active(dev);
> +	pm_runtime_enable(dev);
> +	/*
> +	 * Don't ignore its dependencies with its children
> +	 */
> +	pm_suspend_ignore_children(dev, false);
> +	clk_prepare_enable(data->usb2_refclk);
> +	pm_runtime_get_noresume(dev);
> +
> +	ret = of_platform_populate(node, NULL, NULL, dev);
> +	if (ret) {
> +		dev_err(dev, "failed to create dwc3 core: %d\n", ret);
> +		goto err_pm_disable;
> +	}
> +
> +	/* Enable vbus irq */
> +	dwc3_ti_enable_irqs(data);
> +
> +	connect_detect_work(&data->work);
> +
> +	/* Setting up autosuspend */
> +	pm_runtime_set_autosuspend_delay(dev, DWC3_AM62_AUTOSUSPEND_DELAY);
> +	pm_runtime_use_autosuspend(dev);
> +	pm_runtime_mark_last_busy(dev);
> +	pm_runtime_put_autosuspend(dev);
> +	return 0;
> +
> +err_pm_disable:
> +	clk_disable_unprepare(data->usb2_refclk);
> +	pm_runtime_disable(dev);
> +	pm_runtime_set_suspended(dev);
> +err_clk_disable:
> +	clk_put(data->usb2_refclk);
> +	return ret;
> +}
> +
> +static int dwc3_ti_remove_core(struct device *dev, void *c)
> +{
> +	struct platform_device *pdev = to_platform_device(dev);
> +
> +	platform_device_unregister(pdev);
> +	return 0;
> +}
> +
> +static int dwc3_ti_remove(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct dwc3_data *data = platform_get_drvdata(pdev);
> +	u32 reg;
> +
> +	dwc3_ti_disable_irqs(data);
> +
> +	device_for_each_child(dev, NULL, dwc3_ti_remove_core);
> +
> +	/* Clear mode valid bit */
> +	reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
> +	reg &= ~USBSS_MODE_VALID;
> +	dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
> +
> +	pm_runtime_put_sync(dev);
> +	clk_disable_unprepare(data->usb2_refclk);
> +	pm_runtime_disable(dev);
> +	pm_runtime_set_suspended(dev);
> +
> +	clk_put(data->usb2_refclk);
> +	platform_set_drvdata(pdev, NULL);
> +	return 0;
> +}
> +
> +#ifdef CONFIG_PM
> +static int dwc3_ti_suspend_common(struct device *dev)
> +{
> +	struct dwc3_data *data = dev_get_drvdata(dev);
> +
> +	/* disable irqs */
> +	dwc3_ti_disable_irqs(data);
> +
> +	clk_disable_unprepare(data->usb2_refclk);
> +
> +	return 0;
> +}
> +
> +static int dwc3_ti_resume_common(struct device *dev)
> +{
> +	struct dwc3_data *data = dev_get_drvdata(dev);
> +
> +	clk_prepare_enable(data->usb2_refclk);
> +
> +	/* Enable irqs */
> +	dwc3_ti_enable_irqs(data);
> +
> +	return 0;
> +}
> +
> +static UNIVERSAL_DEV_PM_OPS(dwc3_ti_pm_ops, dwc3_ti_suspend_common,
> +			    dwc3_ti_resume_common, NULL);
> +
> +#define DEV_PM_OPS	(&dwc3_ti_pm_ops)
> +#else
> +#define DEV_PM_OPS	NULL
> +#endif /* CONFIG_PM */
> +
> +static const struct of_device_id dwc3_ti_of_match[] = {
> +	{ .compatible = "ti,am62-usb"},
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, dwc3_ti_of_match);
> +
> +static struct platform_driver dwc3_ti_driver = {
> +	.probe		= dwc3_ti_probe,
> +	.remove		= dwc3_ti_remove,
> +	.driver		= {
> +		.name	= "dwc3-am62",
> +		.pm	= DEV_PM_OPS,
> +		.of_match_table = dwc3_ti_of_match,
> +	},
> +};
> +
> +module_platform_driver(dwc3_ti_driver);
> +
> +MODULE_ALIAS("platform:dwc3-am62");
> +MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
> +MODULE_LICENSE("GPL");
> +MODULE_DESCRIPTION("DesignWare USB3 TI Glue Layer");

Re: [PATCH v3 2/2] drivers: usb: dwc3: Add AM62 USB wrapper driver

[Aswath Govindraju]

Hi Roger,

On 07/04/22 13:29, Roger Quadros wrote:
> Hi Aswath,
> 
> On 06/04/2022 16:52, Aswath Govindraju wrote:
>> In AM62 SoC, the Designware Core USB3 IP is progammed to operate in USB2.0
>> only mode. Add driver for AM62 USB DWC3 Wrapper.
>>
>> Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
>> ---
>>
>> changes since v2:
>> - Removed the implementation of detecting the role from the wrapper
>>   driver and moved the implementation to using linux,extcon-usb-gpio
>>   driver for role detection.
>> - Updated the binding documentation and example to reflect the same.
>>
>>
>>  drivers/usb/dwc3/Kconfig     |   9 +
>>  drivers/usb/dwc3/Makefile    |   1 +
>>  drivers/usb/dwc3/dwc3-am62.c | 446 +++++++++++++++++++++++++++++++++++
>>  3 files changed, 456 insertions(+)
>>  create mode 100644 drivers/usb/dwc3/dwc3-am62.c
>>
>> diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
>> index c483f28b695d..cd9a734522a7 100644
>> --- a/drivers/usb/dwc3/Kconfig
>> +++ b/drivers/usb/dwc3/Kconfig
>> @@ -159,4 +159,13 @@ config USB_DWC3_XILINX
>>  	  This driver handles both ZynqMP and Versal SoC operations.
>>  	  Say 'Y' or 'M' if you have one such device.
>>  
>> +config USB_DWC3_AM62
>> +	tristate "Texas Instruments AM62 Platforms"
>> +	depends on ARCH_K3 || COMPILE_TEST
> 
> Does this need to depend on EXTCON as well if COMPILE_TEST is not set?
> 

The wrapper does not depend on the EXTCON but it is the controller that
uses extcon for getting role updates.

>> +	default USB_DWC3
>> +	help
>> +	  Support TI's AM62 platforms with DesignWare Core USB3 IP.
>> +	  The Designware Core USB3 IP is progammed to operate in
> 
> typo 'programmed'

Sorry, will fix this in the respin.

Thanks,
Aswath

> 
>> +	  in USB 2.0 mode only.
>> +	  Say 'Y' or 'M' here if you have one such device
>>  endif
>> diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
>> index 2d499de6f66a..9f66bd82b639 100644
>> --- a/drivers/usb/dwc3/Makefile
>> +++ b/drivers/usb/dwc3/Makefile
>> @@ -42,6 +42,7 @@ endif
>>  # and allyesconfig builds.
>>  ##
>>  
>> +obj-$(CONFIG_USB_DWC3_AM62)		+= dwc3-am62.o
>>  obj-$(CONFIG_USB_DWC3_OMAP)		+= dwc3-omap.o
>>  obj-$(CONFIG_USB_DWC3_EXYNOS)		+= dwc3-exynos.o
>>  obj-$(CONFIG_USB_DWC3_PCI)		+= dwc3-pci.o
>> diff --git a/drivers/usb/dwc3/dwc3-am62.c b/drivers/usb/dwc3/dwc3-am62.c
>> new file mode 100644
>> index 000000000000..5700258c8deb
>> --- /dev/null
>> +++ b/drivers/usb/dwc3/dwc3-am62.c
>> @@ -0,0 +1,446 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * dwc3-am62.c - TI specific Glue layer for AM62 DWC3 USB Controller
>> + *
>> + * Copyright (C) 2022 Texas Instruments Incorporated - https://www.ti.com
>> + */
>> +
>> +#include <linux/init.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/irq.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/workqueue.h>
>> +#include <linux/mfd/syscon.h>
>> +#include <linux/of.h>
>> +#include <linux/of_device.h>
>> +#include <linux/pm_runtime.h>
>> +#include <linux/clk.h>
>> +#include <linux/regmap.h>
>> +#include <linux/devm-helpers.h>
>> +#include <linux/pinctrl/consumer.h>
>> +
>> +/* USB WRAPPER register offsets */
>> +#define USBSS_PID			0x0
>> +#define USBSS_OVERCURRENT_CTRL		0x4
>> +#define USBSS_PHY_CONFIG		0x8
>> +#define USBSS_PHY_TEST			0xc
>> +#define USBSS_CORE_STAT			0x14
>> +#define USBSS_HOST_VBUS_CTRL		0x18
>> +#define USBSS_MODE_CONTROL		0x1c
>> +#define USBSS_WAKEUP_CONFIG		0x30
>> +#define USBSS_WAKEUP_STAT		0x34
>> +#define USBSS_OVERRIDE_CONFIG		0x38
>> +#define USBSS_IRQ_MISC_STATUS_RAW	0x430
>> +#define USBSS_IRQ_MISC_STATUS		0x434
>> +#define USBSS_IRQ_MISC_ENABLE_SET	0x438
>> +#define USBSS_IRQ_MISC_ENABLE_CLR	0x43c
>> +#define USBSS_IRQ_MISC_EOI		0x440
>> +#define USBSS_INTR_TEST			0x490
>> +#define USBSS_VBUS_FILTER		0x614
>> +#define USBSS_VBUS_STAT			0x618
>> +#define USBSS_DEBUG_CFG			0x708
>> +#define USBSS_DEBUG_DATA		0x70c
>> +#define USBSS_HOST_HUB_CTRL		0x714
>> +
>> +/* PHY CONFIG register bits */
>> +#define USBSS_PHY_VBUS_SEL_MASK		GENMASK(2, 1)
>> +#define USBSS_PHY_VBUS_SEL_SHIFT	1
>> +#define USBSS_PHY_LANE_REVERSE		BIT(0)
>> +
>> +/* MODE CONTROL register bits */
>> +#define USBSS_MODE_VALID	BIT(0)
>> +
>> +/* WAKEUP CONFIG register bits */
>> +#define USBSS_WAKEUP_CFG_OVERCURRENT_EN	BIT(3)
>> +#define USBSS_WAKEUP_CFG_LINESTATE_EN	BIT(2)
>> +#define USBSS_WAKEUP_CFG_SESSVALID_EN	BIT(1)
>> +#define USBSS_WAKEUP_CFG_VBUSVALID_EN	BIT(0)
>> +
>> +/* WAKEUP STAT register bits */
>> +#define USBSS_WAKEUP_STAT_OVERCURRENT	BIT(4)
>> +#define USBSS_WAKEUP_STAT_LINESTATE	BIT(3)
>> +#define USBSS_WAKEUP_STAT_SESSVALID	BIT(2)
>> +#define USBSS_WAKEUP_STAT_VBUSVALID	BIT(1)
>> +#define USBSS_WAKEUP_STAT_CLR		BIT(0)
>> +
>> +/* IRQ_MISC_STATUS_RAW register bits */
>> +#define USBSS_IRQ_MISC_RAW_VBUSVALID	BIT(22)
>> +#define USBSS_IRQ_MISC_RAW_SESSVALID	BIT(20)
>> +
>> +/* IRQ_MISC_STATUS register bits */
>> +#define USBSS_IRQ_MISC_VBUSVALID	BIT(22)
>> +#define USBSS_IRQ_MISC_SESSVALID	BIT(20)
>> +
>> +/* IRQ_MISC_ENABLE_SET register bits */
>> +#define USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID	BIT(22)
>> +#define USBSS_IRQ_MISC_ENABLE_SET_SESSVALID	BIT(20)
>> +
>> +/* IRQ_MISC_ENABLE_CLR register bits */
>> +#define USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID	BIT(22)
>> +#define USBSS_IRQ_MISC_ENABLE_CLR_SESSVALID	BIT(20)
>> +
>> +/* IRQ_MISC_EOI register bits */
>> +#define USBSS_IRQ_MISC_EOI_VECTOR	BIT(0)
>> +
>> +/* VBUS_STAT register bits */
>> +#define USBSS_VBUS_STAT_SESSVALID	BIT(2)
>> +#define USBSS_VBUS_STAT_VBUSVALID	BIT(0)
>> +
>> +/* Mask for PHY PLL REFCLK */
>> +#define PHY_PLL_REFCLK_MASK	GENMASK(3, 0)
>> +
>> +#define DWC3_AM62_AUTOSUSPEND_DELAY	100
>> +
>> +struct dwc3_data {
>> +	struct device *dev;
>> +	void __iomem *usbss;
>> +	struct clk *usb2_refclk;
>> +	struct work_struct work;
>> +	int vbus_irq;
>> +	int rate_code;
>> +	int connect;
>> +	struct regmap *syscon;
>> +	unsigned int offset;
>> +	unsigned int vbus_divider;
>> +};
>> +
>> +static const int dwc3_ti_rate_table[] = {	/* in KHZ */
>> +	9600,
>> +	10000,
>> +	12000,
>> +	19200,
>> +	20000,
>> +	24000,
>> +	25000,
>> +	26000,
>> +	38400,
>> +	40000,
>> +	58000,
>> +	50000,
>> +	52000,
>> +};
>> +
>> +static inline u32 dwc3_ti_readl(struct dwc3_data *data, u32 offset)
>> +{
>> +	return readl((data->usbss) + offset);
>> +}
>> +
>> +static inline void dwc3_ti_writel(struct dwc3_data *data, u32 offset, u32 value)
>> +{
>> +	writel(value, (data->usbss) + offset);
>> +}
>> +
>> +static void connect_detect_work(struct work_struct *work)
>> +{
>> +	struct dwc3_data *data =
>> +		container_of(work, struct dwc3_data, work);
>> +	u32 vbus_state, reg;
>> +	int connect = 0;
>> +
>> +	/* Read the status for VBUS valid register */
>> +	vbus_state = dwc3_ti_readl(data, USBSS_VBUS_STAT);
>> +	vbus_state &= USBSS_VBUS_STAT_VBUSVALID;
>> +
>> +	if (vbus_state)
>> +		connect = 1;
>> +
>> +	/* Set or clear mode valid bit based on connect or disconnect event */
>> +	if (data->connect != connect) {
>> +		reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
>> +		if (connect)
>> +			reg |= USBSS_MODE_VALID;
>> +		else
>> +			reg &= ~USBSS_MODE_VALID;
>> +
>> +		dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
>> +		data->connect = connect;
>> +	}
>> +}
>> +
>> +static irqreturn_t connect_detect_irq_handler(int irq, void *dev_id)
>> +{
>> +	struct dwc3_data *data = dev_id;
>> +	u32 reg;
>> +
>> +	/* Clear VBUS interrupt always to aviod queuing up redundant work items */
>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_STATUS);
>> +	reg |= USBSS_IRQ_MISC_VBUSVALID;
>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_STATUS, reg);
>> +
>> +	queue_work(system_power_efficient_wq, &data->work);
>> +
>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_EOI);
>> +	reg &= ~USBSS_IRQ_MISC_EOI_VECTOR;
>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_EOI, reg);
>> +	return IRQ_HANDLED;
>> +}
>> +
>> +static int dwc3_ti_vbus_irq_setup(struct platform_device *pdev)
>> +{
>> +	struct device *dev = &pdev->dev;
>> +	struct dwc3_data *data = platform_get_drvdata(pdev);
>> +	int irq, ret;
>> +
>> +	/* Get the misc interrupt */
>> +	irq = platform_get_irq(pdev, 0);
>> +	if (irq < 0)
>> +		return irq;
>> +
>> +	ret = devm_request_irq(dev, irq, connect_detect_irq_handler, IRQF_SHARED,
>> +			       dev_name(dev), data);
>> +	if (ret) {
>> +		dev_err(dev, "failed to required IRQ #%d-->%d\n",
>> +			irq, ret);
>> +		return ret;
>> +	}
>> +
>> +	data->vbus_irq = irq;
>> +
>> +	return 0;
>> +}
>> +
>> +static int phy_syscon_pll_refclk(struct dwc3_data *data)
>> +{
>> +	struct device *dev = data->dev;
>> +	struct device_node *node = dev->of_node;
>> +	struct of_phandle_args args;
>> +	struct regmap *syscon;
>> +	int ret;
>> +
>> +	syscon = syscon_regmap_lookup_by_phandle(node, "ti,syscon-phy-pll-refclk");
>> +	if (IS_ERR(syscon)) {
>> +		dev_err(dev, "unable to get ti,syscon-phy-pll-refclk regmap\n");
>> +		return PTR_ERR(syscon);
>> +	}
>> +
>> +	data->syscon = syscon;
>> +
>> +	ret = of_parse_phandle_with_fixed_args(node, "ti,syscon-phy-pll-refclk", 1,
>> +					       0, &args);
>> +	if (ret)
>> +		return ret;
>> +
>> +	data->offset = args.args[0];
>> +
>> +	ret = regmap_update_bits(data->syscon, data->offset, PHY_PLL_REFCLK_MASK, data->rate_code);
>> +	if (ret) {
>> +		dev_err(dev, "failed to set phy pll reference clock rate\n");
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static void dwc3_ti_enable_irqs(struct dwc3_data *data)
>> +{
>> +	u32 reg;
>> +
>> +	/* enable VBUSVALID interrupt */
>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_ENABLE_SET);
>> +	reg |= USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID;
>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_ENABLE_SET, reg);
>> +}
>> +
>> +static void dwc3_ti_disable_irqs(struct dwc3_data *data)
>> +{
>> +	u32 reg;
>> +
>> +	/* disable VBUSVALID interrupt */
>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_ENABLE_CLR);
>> +	reg |= USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID;
>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_ENABLE_CLR, reg);
>> +}
>> +
>> +static int dwc3_ti_probe(struct platform_device *pdev)
>> +{
>> +	struct device *dev = &pdev->dev;
>> +	struct device_node *node = pdev->dev.of_node;
>> +	struct dwc3_data *data;
>> +	int i, ret;
>> +	unsigned long rate;
>> +	u32 reg;
>> +
>> +	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
>> +	if (!data)
>> +		return -ENOMEM;
>> +
>> +	data->dev = dev;
>> +	platform_set_drvdata(pdev, data);
>> +
>> +	data->usbss = devm_platform_ioremap_resource(pdev, 0);
>> +	if (IS_ERR(data->usbss)) {
>> +		dev_err(dev, "can't map IOMEM resource\n");
>> +		return PTR_ERR(data->usbss);
>> +	}
>> +
>> +	data->usb2_refclk = devm_clk_get(dev, "ref");
>> +	if (IS_ERR(data->usb2_refclk)) {
>> +		dev_err(dev, "can't get usb2_refclk\n");
>> +		return PTR_ERR(data->usb2_refclk);
>> +	}
>> +
>> +	/* Calculate the rate code */
>> +	rate = clk_get_rate(data->usb2_refclk);
>> +	rate /= 1000;	// To KHz
>> +	for (i = 0; i < ARRAY_SIZE(dwc3_ti_rate_table); i++) {
>> +		if (dwc3_ti_rate_table[i] == rate)
>> +			break;
>> +	}
>> +
>> +	if (i == ARRAY_SIZE(dwc3_ti_rate_table)) {
>> +		dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate);
>> +		ret = -EINVAL;
>> +		goto err_clk_disable;
>> +	}
>> +
>> +	data->rate_code = i;
>> +
>> +	/* Read the syscon property and set the rate code */
>> +	ret = phy_syscon_pll_refclk(data);
>> +	if (ret)
>> +		goto err_clk_disable;
>> +
>> +	/* VBUS divider select */
>> +	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
>> +	reg = dwc3_ti_readl(data, USBSS_PHY_CONFIG);
>> +	if (data->vbus_divider)
>> +		reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT;
>> +
>> +	dwc3_ti_writel(data, USBSS_PHY_CONFIG, reg);
>> +
>> +	/* Initialize a work queue */
>> +	ret = devm_work_autocancel(dev, &data->work, connect_detect_work);
>> +	if (ret)
>> +		goto err_clk_disable;
>> +
>> +	/* Read and set VBUS IRQ */
>> +	ret = dwc3_ti_vbus_irq_setup(pdev);
>> +	if (ret)
>> +		goto err_clk_disable;
>> +
>> +	pm_runtime_set_active(dev);
>> +	pm_runtime_enable(dev);
>> +	/*
>> +	 * Don't ignore its dependencies with its children
>> +	 */
>> +	pm_suspend_ignore_children(dev, false);
>> +	clk_prepare_enable(data->usb2_refclk);
>> +	pm_runtime_get_noresume(dev);
>> +
>> +	ret = of_platform_populate(node, NULL, NULL, dev);
>> +	if (ret) {
>> +		dev_err(dev, "failed to create dwc3 core: %d\n", ret);
>> +		goto err_pm_disable;
>> +	}
>> +
>> +	/* Enable vbus irq */
>> +	dwc3_ti_enable_irqs(data);
>> +
>> +	connect_detect_work(&data->work);
>> +
>> +	/* Setting up autosuspend */
>> +	pm_runtime_set_autosuspend_delay(dev, DWC3_AM62_AUTOSUSPEND_DELAY);
>> +	pm_runtime_use_autosuspend(dev);
>> +	pm_runtime_mark_last_busy(dev);
>> +	pm_runtime_put_autosuspend(dev);
>> +	return 0;
>> +
>> +err_pm_disable:
>> +	clk_disable_unprepare(data->usb2_refclk);
>> +	pm_runtime_disable(dev);
>> +	pm_runtime_set_suspended(dev);
>> +err_clk_disable:
>> +	clk_put(data->usb2_refclk);
>> +	return ret;
>> +}
>> +
>> +static int dwc3_ti_remove_core(struct device *dev, void *c)
>> +{
>> +	struct platform_device *pdev = to_platform_device(dev);
>> +
>> +	platform_device_unregister(pdev);
>> +	return 0;
>> +}
>> +
>> +static int dwc3_ti_remove(struct platform_device *pdev)
>> +{
>> +	struct device *dev = &pdev->dev;
>> +	struct dwc3_data *data = platform_get_drvdata(pdev);
>> +	u32 reg;
>> +
>> +	dwc3_ti_disable_irqs(data);
>> +
>> +	device_for_each_child(dev, NULL, dwc3_ti_remove_core);
>> +
>> +	/* Clear mode valid bit */
>> +	reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
>> +	reg &= ~USBSS_MODE_VALID;
>> +	dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
>> +
>> +	pm_runtime_put_sync(dev);
>> +	clk_disable_unprepare(data->usb2_refclk);
>> +	pm_runtime_disable(dev);
>> +	pm_runtime_set_suspended(dev);
>> +
>> +	clk_put(data->usb2_refclk);
>> +	platform_set_drvdata(pdev, NULL);
>> +	return 0;
>> +}
>> +
>> +#ifdef CONFIG_PM
>> +static int dwc3_ti_suspend_common(struct device *dev)
>> +{
>> +	struct dwc3_data *data = dev_get_drvdata(dev);
>> +
>> +	/* disable irqs */
>> +	dwc3_ti_disable_irqs(data);
>> +
>> +	clk_disable_unprepare(data->usb2_refclk);
>> +
>> +	return 0;
>> +}
>> +
>> +static int dwc3_ti_resume_common(struct device *dev)
>> +{
>> +	struct dwc3_data *data = dev_get_drvdata(dev);
>> +
>> +	clk_prepare_enable(data->usb2_refclk);
>> +
>> +	/* Enable irqs */
>> +	dwc3_ti_enable_irqs(data);
>> +
>> +	return 0;
>> +}
>> +
>> +static UNIVERSAL_DEV_PM_OPS(dwc3_ti_pm_ops, dwc3_ti_suspend_common,
>> +			    dwc3_ti_resume_common, NULL);
>> +
>> +#define DEV_PM_OPS	(&dwc3_ti_pm_ops)
>> +#else
>> +#define DEV_PM_OPS	NULL
>> +#endif /* CONFIG_PM */
>> +
>> +static const struct of_device_id dwc3_ti_of_match[] = {
>> +	{ .compatible = "ti,am62-usb"},
>> +	{},
>> +};
>> +MODULE_DEVICE_TABLE(of, dwc3_ti_of_match);
>> +
>> +static struct platform_driver dwc3_ti_driver = {
>> +	.probe		= dwc3_ti_probe,
>> +	.remove		= dwc3_ti_remove,
>> +	.driver		= {
>> +		.name	= "dwc3-am62",
>> +		.pm	= DEV_PM_OPS,
>> +		.of_match_table = dwc3_ti_of_match,
>> +	},
>> +};
>> +
>> +module_platform_driver(dwc3_ti_driver);
>> +
>> +MODULE_ALIAS("platform:dwc3-am62");
>> +MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
>> +MODULE_LICENSE("GPL");
>> +MODULE_DESCRIPTION("DesignWare USB3 TI Glue Layer")

Re: [PATCH v3 2/2] drivers: usb: dwc3: Add AM62 USB wrapper driver

[Roger Quadros]

Hi Aswath,

On 06/04/2022 16:52, Aswath Govindraju wrote:
> In AM62 SoC, the Designware Core USB3 IP is progammed to operate in USB2.0
> only mode. Add driver for AM62 USB DWC3 Wrapper.
> 
> Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
> ---
> 
> changes since v2:
> - Removed the implementation of detecting the role from the wrapper
>   driver and moved the implementation to using linux,extcon-usb-gpio
>   driver for role detection.

I'm a bit puzzled. So ID is managed by extcon-usb-gpio driver and
VBUS is managed by this driver.

So who decides the USB ports state based on the below truth table?

+	/*
+	 * ID | VBUS | STATE
+	 * -----------------
+	 * 0  | 0    | HOST
+	 * 0  | 1    | HOST
+	 * 1  | 0    | Disconnected (set mode valid to 0)
+	 * 1  | 1    | Device
+	 *
+	 */

If only ID signal is available to extcon-usb-gpio driver it cannot detect
the Disconnected state. We need to set mode valid to 0 for disconnected state.

cheers,
-roger


> - Updated the binding documentation and example to reflect the same.
> 
> 
>  drivers/usb/dwc3/Kconfig     |   9 +
>  drivers/usb/dwc3/Makefile    |   1 +
>  drivers/usb/dwc3/dwc3-am62.c | 446 +++++++++++++++++++++++++++++++++++
>  3 files changed, 456 insertions(+)
>  create mode 100644 drivers/usb/dwc3/dwc3-am62.c
> 
> diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
> index c483f28b695d..cd9a734522a7 100644
> --- a/drivers/usb/dwc3/Kconfig
> +++ b/drivers/usb/dwc3/Kconfig
> @@ -159,4 +159,13 @@ config USB_DWC3_XILINX
>  	  This driver handles both ZynqMP and Versal SoC operations.
>  	  Say 'Y' or 'M' if you have one such device.
>  
> +config USB_DWC3_AM62
> +	tristate "Texas Instruments AM62 Platforms"
> +	depends on ARCH_K3 || COMPILE_TEST
> +	default USB_DWC3
> +	help
> +	  Support TI's AM62 platforms with DesignWare Core USB3 IP.
> +	  The Designware Core USB3 IP is progammed to operate in
> +	  in USB 2.0 mode only.
> +	  Say 'Y' or 'M' here if you have one such device
>  endif
> diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
> index 2d499de6f66a..9f66bd82b639 100644
> --- a/drivers/usb/dwc3/Makefile
> +++ b/drivers/usb/dwc3/Makefile
> @@ -42,6 +42,7 @@ endif
>  # and allyesconfig builds.
>  ##
>  
> +obj-$(CONFIG_USB_DWC3_AM62)		+= dwc3-am62.o
>  obj-$(CONFIG_USB_DWC3_OMAP)		+= dwc3-omap.o
>  obj-$(CONFIG_USB_DWC3_EXYNOS)		+= dwc3-exynos.o
>  obj-$(CONFIG_USB_DWC3_PCI)		+= dwc3-pci.o
> diff --git a/drivers/usb/dwc3/dwc3-am62.c b/drivers/usb/dwc3/dwc3-am62.c
> new file mode 100644
> index 000000000000..5700258c8deb
> --- /dev/null
> +++ b/drivers/usb/dwc3/dwc3-am62.c
> @@ -0,0 +1,446 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * dwc3-am62.c - TI specific Glue layer for AM62 DWC3 USB Controller
> + *
> + * Copyright (C) 2022 Texas Instruments Incorporated - https://www.ti.com
> + */
> +
> +#include <linux/init.h>
> +#include <linux/interrupt.h>
> +#include <linux/irq.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/workqueue.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/clk.h>
> +#include <linux/regmap.h>
> +#include <linux/devm-helpers.h>
> +#include <linux/pinctrl/consumer.h>
> +
> +/* USB WRAPPER register offsets */
> +#define USBSS_PID			0x0
> +#define USBSS_OVERCURRENT_CTRL		0x4
> +#define USBSS_PHY_CONFIG		0x8
> +#define USBSS_PHY_TEST			0xc
> +#define USBSS_CORE_STAT			0x14
> +#define USBSS_HOST_VBUS_CTRL		0x18
> +#define USBSS_MODE_CONTROL		0x1c
> +#define USBSS_WAKEUP_CONFIG		0x30
> +#define USBSS_WAKEUP_STAT		0x34
> +#define USBSS_OVERRIDE_CONFIG		0x38
> +#define USBSS_IRQ_MISC_STATUS_RAW	0x430
> +#define USBSS_IRQ_MISC_STATUS		0x434
> +#define USBSS_IRQ_MISC_ENABLE_SET	0x438
> +#define USBSS_IRQ_MISC_ENABLE_CLR	0x43c
> +#define USBSS_IRQ_MISC_EOI		0x440
> +#define USBSS_INTR_TEST			0x490
> +#define USBSS_VBUS_FILTER		0x614
> +#define USBSS_VBUS_STAT			0x618
> +#define USBSS_DEBUG_CFG			0x708
> +#define USBSS_DEBUG_DATA		0x70c
> +#define USBSS_HOST_HUB_CTRL		0x714
> +
> +/* PHY CONFIG register bits */
> +#define USBSS_PHY_VBUS_SEL_MASK		GENMASK(2, 1)
> +#define USBSS_PHY_VBUS_SEL_SHIFT	1
> +#define USBSS_PHY_LANE_REVERSE		BIT(0)
> +
> +/* MODE CONTROL register bits */
> +#define USBSS_MODE_VALID	BIT(0)
> +
> +/* WAKEUP CONFIG register bits */
> +#define USBSS_WAKEUP_CFG_OVERCURRENT_EN	BIT(3)
> +#define USBSS_WAKEUP_CFG_LINESTATE_EN	BIT(2)
> +#define USBSS_WAKEUP_CFG_SESSVALID_EN	BIT(1)
> +#define USBSS_WAKEUP_CFG_VBUSVALID_EN	BIT(0)
> +
> +/* WAKEUP STAT register bits */
> +#define USBSS_WAKEUP_STAT_OVERCURRENT	BIT(4)
> +#define USBSS_WAKEUP_STAT_LINESTATE	BIT(3)
> +#define USBSS_WAKEUP_STAT_SESSVALID	BIT(2)
> +#define USBSS_WAKEUP_STAT_VBUSVALID	BIT(1)
> +#define USBSS_WAKEUP_STAT_CLR		BIT(0)
> +
> +/* IRQ_MISC_STATUS_RAW register bits */
> +#define USBSS_IRQ_MISC_RAW_VBUSVALID	BIT(22)
> +#define USBSS_IRQ_MISC_RAW_SESSVALID	BIT(20)
> +
> +/* IRQ_MISC_STATUS register bits */
> +#define USBSS_IRQ_MISC_VBUSVALID	BIT(22)
> +#define USBSS_IRQ_MISC_SESSVALID	BIT(20)
> +
> +/* IRQ_MISC_ENABLE_SET register bits */
> +#define USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID	BIT(22)
> +#define USBSS_IRQ_MISC_ENABLE_SET_SESSVALID	BIT(20)
> +
> +/* IRQ_MISC_ENABLE_CLR register bits */
> +#define USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID	BIT(22)
> +#define USBSS_IRQ_MISC_ENABLE_CLR_SESSVALID	BIT(20)
> +
> +/* IRQ_MISC_EOI register bits */
> +#define USBSS_IRQ_MISC_EOI_VECTOR	BIT(0)
> +
> +/* VBUS_STAT register bits */
> +#define USBSS_VBUS_STAT_SESSVALID	BIT(2)
> +#define USBSS_VBUS_STAT_VBUSVALID	BIT(0)
> +
> +/* Mask for PHY PLL REFCLK */
> +#define PHY_PLL_REFCLK_MASK	GENMASK(3, 0)
> +
> +#define DWC3_AM62_AUTOSUSPEND_DELAY	100
> +
> +struct dwc3_data {
> +	struct device *dev;
> +	void __iomem *usbss;
> +	struct clk *usb2_refclk;
> +	struct work_struct work;
> +	int vbus_irq;
> +	int rate_code;
> +	int connect;
> +	struct regmap *syscon;
> +	unsigned int offset;
> +	unsigned int vbus_divider;
> +};
> +
> +static const int dwc3_ti_rate_table[] = {	/* in KHZ */
> +	9600,
> +	10000,
> +	12000,
> +	19200,
> +	20000,
> +	24000,
> +	25000,
> +	26000,
> +	38400,
> +	40000,
> +	58000,
> +	50000,
> +	52000,
> +};
> +
> +static inline u32 dwc3_ti_readl(struct dwc3_data *data, u32 offset)
> +{
> +	return readl((data->usbss) + offset);
> +}
> +
> +static inline void dwc3_ti_writel(struct dwc3_data *data, u32 offset, u32 value)
> +{
> +	writel(value, (data->usbss) + offset);
> +}
> +
> +static void connect_detect_work(struct work_struct *work)
> +{
> +	struct dwc3_data *data =
> +		container_of(work, struct dwc3_data, work);
> +	u32 vbus_state, reg;
> +	int connect = 0;
> +
> +	/* Read the status for VBUS valid register */
> +	vbus_state = dwc3_ti_readl(data, USBSS_VBUS_STAT);
> +	vbus_state &= USBSS_VBUS_STAT_VBUSVALID;
> +
> +	if (vbus_state)
> +		connect = 1;
> +
> +	/* Set or clear mode valid bit based on connect or disconnect event */
> +	if (data->connect != connect) {
> +		reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
> +		if (connect)
> +			reg |= USBSS_MODE_VALID;
> +		else
> +			reg &= ~USBSS_MODE_VALID;
> +
> +		dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
> +		data->connect = connect;
> +	}
> +}
> +
> +static irqreturn_t connect_detect_irq_handler(int irq, void *dev_id)
> +{
> +	struct dwc3_data *data = dev_id;
> +	u32 reg;
> +
> +	/* Clear VBUS interrupt always to aviod queuing up redundant work items */
> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_STATUS);
> +	reg |= USBSS_IRQ_MISC_VBUSVALID;
> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_STATUS, reg);
> +
> +	queue_work(system_power_efficient_wq, &data->work);
> +
> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_EOI);
> +	reg &= ~USBSS_IRQ_MISC_EOI_VECTOR;
> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_EOI, reg);
> +	return IRQ_HANDLED;
> +}
> +
> +static int dwc3_ti_vbus_irq_setup(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct dwc3_data *data = platform_get_drvdata(pdev);
> +	int irq, ret;
> +
> +	/* Get the misc interrupt */
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0)
> +		return irq;
> +
> +	ret = devm_request_irq(dev, irq, connect_detect_irq_handler, IRQF_SHARED,
> +			       dev_name(dev), data);
> +	if (ret) {
> +		dev_err(dev, "failed to required IRQ #%d-->%d\n",
> +			irq, ret);
> +		return ret;
> +	}
> +
> +	data->vbus_irq = irq;
> +
> +	return 0;
> +}
> +
> +static int phy_syscon_pll_refclk(struct dwc3_data *data)
> +{
> +	struct device *dev = data->dev;
> +	struct device_node *node = dev->of_node;
> +	struct of_phandle_args args;
> +	struct regmap *syscon;
> +	int ret;
> +
> +	syscon = syscon_regmap_lookup_by_phandle(node, "ti,syscon-phy-pll-refclk");
> +	if (IS_ERR(syscon)) {
> +		dev_err(dev, "unable to get ti,syscon-phy-pll-refclk regmap\n");
> +		return PTR_ERR(syscon);
> +	}
> +
> +	data->syscon = syscon;
> +
> +	ret = of_parse_phandle_with_fixed_args(node, "ti,syscon-phy-pll-refclk", 1,
> +					       0, &args);
> +	if (ret)
> +		return ret;
> +
> +	data->offset = args.args[0];
> +
> +	ret = regmap_update_bits(data->syscon, data->offset, PHY_PLL_REFCLK_MASK, data->rate_code);
> +	if (ret) {
> +		dev_err(dev, "failed to set phy pll reference clock rate\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static void dwc3_ti_enable_irqs(struct dwc3_data *data)
> +{
> +	u32 reg;
> +
> +	/* enable VBUSVALID interrupt */
> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_ENABLE_SET);
> +	reg |= USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID;
> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_ENABLE_SET, reg);
> +}
> +
> +static void dwc3_ti_disable_irqs(struct dwc3_data *data)
> +{
> +	u32 reg;
> +
> +	/* disable VBUSVALID interrupt */
> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_ENABLE_CLR);
> +	reg |= USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID;
> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_ENABLE_CLR, reg);
> +}
> +
> +static int dwc3_ti_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct device_node *node = pdev->dev.of_node;
> +	struct dwc3_data *data;
> +	int i, ret;
> +	unsigned long rate;
> +	u32 reg;
> +
> +	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> +	if (!data)
> +		return -ENOMEM;
> +
> +	data->dev = dev;
> +	platform_set_drvdata(pdev, data);
> +
> +	data->usbss = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(data->usbss)) {
> +		dev_err(dev, "can't map IOMEM resource\n");
> +		return PTR_ERR(data->usbss);
> +	}
> +
> +	data->usb2_refclk = devm_clk_get(dev, "ref");
> +	if (IS_ERR(data->usb2_refclk)) {
> +		dev_err(dev, "can't get usb2_refclk\n");
> +		return PTR_ERR(data->usb2_refclk);
> +	}
> +
> +	/* Calculate the rate code */
> +	rate = clk_get_rate(data->usb2_refclk);
> +	rate /= 1000;	// To KHz
> +	for (i = 0; i < ARRAY_SIZE(dwc3_ti_rate_table); i++) {
> +		if (dwc3_ti_rate_table[i] == rate)
> +			break;
> +	}
> +
> +	if (i == ARRAY_SIZE(dwc3_ti_rate_table)) {
> +		dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate);
> +		ret = -EINVAL;
> +		goto err_clk_disable;
> +	}
> +
> +	data->rate_code = i;
> +
> +	/* Read the syscon property and set the rate code */
> +	ret = phy_syscon_pll_refclk(data);
> +	if (ret)
> +		goto err_clk_disable;
> +
> +	/* VBUS divider select */
> +	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
> +	reg = dwc3_ti_readl(data, USBSS_PHY_CONFIG);
> +	if (data->vbus_divider)
> +		reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT;
> +
> +	dwc3_ti_writel(data, USBSS_PHY_CONFIG, reg);
> +
> +	/* Initialize a work queue */
> +	ret = devm_work_autocancel(dev, &data->work, connect_detect_work);
> +	if (ret)
> +		goto err_clk_disable;
> +
> +	/* Read and set VBUS IRQ */
> +	ret = dwc3_ti_vbus_irq_setup(pdev);
> +	if (ret)
> +		goto err_clk_disable;
> +
> +	pm_runtime_set_active(dev);
> +	pm_runtime_enable(dev);
> +	/*
> +	 * Don't ignore its dependencies with its children
> +	 */
> +	pm_suspend_ignore_children(dev, false);
> +	clk_prepare_enable(data->usb2_refclk);
> +	pm_runtime_get_noresume(dev);
> +
> +	ret = of_platform_populate(node, NULL, NULL, dev);
> +	if (ret) {
> +		dev_err(dev, "failed to create dwc3 core: %d\n", ret);
> +		goto err_pm_disable;
> +	}
> +
> +	/* Enable vbus irq */
> +	dwc3_ti_enable_irqs(data);
> +
> +	connect_detect_work(&data->work);
> +
> +	/* Setting up autosuspend */
> +	pm_runtime_set_autosuspend_delay(dev, DWC3_AM62_AUTOSUSPEND_DELAY);
> +	pm_runtime_use_autosuspend(dev);
> +	pm_runtime_mark_last_busy(dev);
> +	pm_runtime_put_autosuspend(dev);
> +	return 0;
> +
> +err_pm_disable:
> +	clk_disable_unprepare(data->usb2_refclk);
> +	pm_runtime_disable(dev);
> +	pm_runtime_set_suspended(dev);
> +err_clk_disable:
> +	clk_put(data->usb2_refclk);
> +	return ret;
> +}
> +
> +static int dwc3_ti_remove_core(struct device *dev, void *c)
> +{
> +	struct platform_device *pdev = to_platform_device(dev);
> +
> +	platform_device_unregister(pdev);
> +	return 0;
> +}
> +
> +static int dwc3_ti_remove(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct dwc3_data *data = platform_get_drvdata(pdev);
> +	u32 reg;
> +
> +	dwc3_ti_disable_irqs(data);
> +
> +	device_for_each_child(dev, NULL, dwc3_ti_remove_core);
> +
> +	/* Clear mode valid bit */
> +	reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
> +	reg &= ~USBSS_MODE_VALID;
> +	dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
> +
> +	pm_runtime_put_sync(dev);
> +	clk_disable_unprepare(data->usb2_refclk);
> +	pm_runtime_disable(dev);
> +	pm_runtime_set_suspended(dev);
> +
> +	clk_put(data->usb2_refclk);
> +	platform_set_drvdata(pdev, NULL);
> +	return 0;
> +}
> +
> +#ifdef CONFIG_PM
> +static int dwc3_ti_suspend_common(struct device *dev)
> +{
> +	struct dwc3_data *data = dev_get_drvdata(dev);
> +
> +	/* disable irqs */
> +	dwc3_ti_disable_irqs(data);
> +
> +	clk_disable_unprepare(data->usb2_refclk);
> +
> +	return 0;
> +}
> +
> +static int dwc3_ti_resume_common(struct device *dev)
> +{
> +	struct dwc3_data *data = dev_get_drvdata(dev);
> +
> +	clk_prepare_enable(data->usb2_refclk);
> +
> +	/* Enable irqs */
> +	dwc3_ti_enable_irqs(data);
> +
> +	return 0;
> +}
> +
> +static UNIVERSAL_DEV_PM_OPS(dwc3_ti_pm_ops, dwc3_ti_suspend_common,
> +			    dwc3_ti_resume_common, NULL);
> +
> +#define DEV_PM_OPS	(&dwc3_ti_pm_ops)
> +#else
> +#define DEV_PM_OPS	NULL
> +#endif /* CONFIG_PM */
> +
> +static const struct of_device_id dwc3_ti_of_match[] = {
> +	{ .compatible = "ti,am62-usb"},
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, dwc3_ti_of_match);
> +
> +static struct platform_driver dwc3_ti_driver = {
> +	.probe		= dwc3_ti_probe,
> +	.remove		= dwc3_ti_remove,
> +	.driver		= {
> +		.name	= "dwc3-am62",
> +		.pm	= DEV_PM_OPS,
> +		.of_match_table = dwc3_ti_of_match,
> +	},
> +};
> +
> +module_platform_driver(dwc3_ti_driver);
> +
> +MODULE_ALIAS("platform:dwc3-am62");
> +MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
> +MODULE_LICENSE("GPL");
> +MODULE_DESCRIPTION("DesignWare USB3 TI Glue Layer");

Re: [PATCH v3 2/2] drivers: usb: dwc3: Add AM62 USB wrapper driver

[Aswath Govindraju]

Hi Roger,

On 07/04/22 13:50, Roger Quadros wrote:
> Hi Aswath,
> 
> On 06/04/2022 16:52, Aswath Govindraju wrote:
>> In AM62 SoC, the Designware Core USB3 IP is progammed to operate in USB2.0
>> only mode. Add driver for AM62 USB DWC3 Wrapper.
>>
>> Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
>> ---
>>
>> changes since v2:
>> - Removed the implementation of detecting the role from the wrapper
>>   driver and moved the implementation to using linux,extcon-usb-gpio
>>   driver for role detection.
> 
> I'm a bit puzzled. So ID is managed by extcon-usb-gpio driver and
> VBUS is managed by this driver.
> 
> So who decides the USB ports state based on the below truth table?
> 
> +	/*
> +	 * ID | VBUS | STATE
> +	 * -----------------
> +	 * 0  | 0    | HOST
> +	 * 0  | 1    | HOST
> +	 * 1  | 0    | Disconnected (set mode valid to 0)
> +	 * 1  | 1    | Device
> +	 *
> +	 */
> 
> If only ID signal is available to extcon-usb-gpio driver it cannot detect
> the Disconnected state. We need to set mode valid to 0 for disconnected state.
> 

Yes that is correct, the mode valid signal needs to be set when there is
no cable connected. I am slightly confused on why 0-0 state is not
considered disconnected? So, whenever VBUS is not high it should be
disconnected right?

Thanks,
Aswath

> cheers,
> -roger
> 
> 
>> - Updated the binding documentation and example to reflect the same.
>>
>>
>>  drivers/usb/dwc3/Kconfig     |   9 +
>>  drivers/usb/dwc3/Makefile    |   1 +
>>  drivers/usb/dwc3/dwc3-am62.c | 446 +++++++++++++++++++++++++++++++++++
>>  3 files changed, 456 insertions(+)
>>  create mode 100644 drivers/usb/dwc3/dwc3-am62.c
>>
>> diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
>> index c483f28b695d..cd9a734522a7 100644
>> --- a/drivers/usb/dwc3/Kconfig
>> +++ b/drivers/usb/dwc3/Kconfig
>> @@ -159,4 +159,13 @@ config USB_DWC3_XILINX
>>  	  This driver handles both ZynqMP and Versal SoC operations.
>>  	  Say 'Y' or 'M' if you have one such device.
>>  
>> +config USB_DWC3_AM62
>> +	tristate "Texas Instruments AM62 Platforms"
>> +	depends on ARCH_K3 || COMPILE_TEST
>> +	default USB_DWC3
>> +	help
>> +	  Support TI's AM62 platforms with DesignWare Core USB3 IP.
>> +	  The Designware Core USB3 IP is progammed to operate in
>> +	  in USB 2.0 mode only.
>> +	  Say 'Y' or 'M' here if you have one such device
>>  endif
>> diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
>> index 2d499de6f66a..9f66bd82b639 100644
>> --- a/drivers/usb/dwc3/Makefile
>> +++ b/drivers/usb/dwc3/Makefile
>> @@ -42,6 +42,7 @@ endif
>>  # and allyesconfig builds.
>>  ##
>>  
>> +obj-$(CONFIG_USB_DWC3_AM62)		+= dwc3-am62.o
>>  obj-$(CONFIG_USB_DWC3_OMAP)		+= dwc3-omap.o
>>  obj-$(CONFIG_USB_DWC3_EXYNOS)		+= dwc3-exynos.o
>>  obj-$(CONFIG_USB_DWC3_PCI)		+= dwc3-pci.o
>> diff --git a/drivers/usb/dwc3/dwc3-am62.c b/drivers/usb/dwc3/dwc3-am62.c
>> new file mode 100644
>> index 000000000000..5700258c8deb
>> --- /dev/null
>> +++ b/drivers/usb/dwc3/dwc3-am62.c
>> @@ -0,0 +1,446 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * dwc3-am62.c - TI specific Glue layer for AM62 DWC3 USB Controller
>> + *
>> + * Copyright (C) 2022 Texas Instruments Incorporated - https://www.ti.com
>> + */
>> +
>> +#include <linux/init.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/irq.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/workqueue.h>
>> +#include <linux/mfd/syscon.h>
>> +#include <linux/of.h>
>> +#include <linux/of_device.h>
>> +#include <linux/pm_runtime.h>
>> +#include <linux/clk.h>
>> +#include <linux/regmap.h>
>> +#include <linux/devm-helpers.h>
>> +#include <linux/pinctrl/consumer.h>
>> +
>> +/* USB WRAPPER register offsets */
>> +#define USBSS_PID			0x0
>> +#define USBSS_OVERCURRENT_CTRL		0x4
>> +#define USBSS_PHY_CONFIG		0x8
>> +#define USBSS_PHY_TEST			0xc
>> +#define USBSS_CORE_STAT			0x14
>> +#define USBSS_HOST_VBUS_CTRL		0x18
>> +#define USBSS_MODE_CONTROL		0x1c
>> +#define USBSS_WAKEUP_CONFIG		0x30
>> +#define USBSS_WAKEUP_STAT		0x34
>> +#define USBSS_OVERRIDE_CONFIG		0x38
>> +#define USBSS_IRQ_MISC_STATUS_RAW	0x430
>> +#define USBSS_IRQ_MISC_STATUS		0x434
>> +#define USBSS_IRQ_MISC_ENABLE_SET	0x438
>> +#define USBSS_IRQ_MISC_ENABLE_CLR	0x43c
>> +#define USBSS_IRQ_MISC_EOI		0x440
>> +#define USBSS_INTR_TEST			0x490
>> +#define USBSS_VBUS_FILTER		0x614
>> +#define USBSS_VBUS_STAT			0x618
>> +#define USBSS_DEBUG_CFG			0x708
>> +#define USBSS_DEBUG_DATA		0x70c
>> +#define USBSS_HOST_HUB_CTRL		0x714
>> +
>> +/* PHY CONFIG register bits */
>> +#define USBSS_PHY_VBUS_SEL_MASK		GENMASK(2, 1)
>> +#define USBSS_PHY_VBUS_SEL_SHIFT	1
>> +#define USBSS_PHY_LANE_REVERSE		BIT(0)
>> +
>> +/* MODE CONTROL register bits */
>> +#define USBSS_MODE_VALID	BIT(0)
>> +
>> +/* WAKEUP CONFIG register bits */
>> +#define USBSS_WAKEUP_CFG_OVERCURRENT_EN	BIT(3)
>> +#define USBSS_WAKEUP_CFG_LINESTATE_EN	BIT(2)
>> +#define USBSS_WAKEUP_CFG_SESSVALID_EN	BIT(1)
>> +#define USBSS_WAKEUP_CFG_VBUSVALID_EN	BIT(0)
>> +
>> +/* WAKEUP STAT register bits */
>> +#define USBSS_WAKEUP_STAT_OVERCURRENT	BIT(4)
>> +#define USBSS_WAKEUP_STAT_LINESTATE	BIT(3)
>> +#define USBSS_WAKEUP_STAT_SESSVALID	BIT(2)
>> +#define USBSS_WAKEUP_STAT_VBUSVALID	BIT(1)
>> +#define USBSS_WAKEUP_STAT_CLR		BIT(0)
>> +
>> +/* IRQ_MISC_STATUS_RAW register bits */
>> +#define USBSS_IRQ_MISC_RAW_VBUSVALID	BIT(22)
>> +#define USBSS_IRQ_MISC_RAW_SESSVALID	BIT(20)
>> +
>> +/* IRQ_MISC_STATUS register bits */
>> +#define USBSS_IRQ_MISC_VBUSVALID	BIT(22)
>> +#define USBSS_IRQ_MISC_SESSVALID	BIT(20)
>> +
>> +/* IRQ_MISC_ENABLE_SET register bits */
>> +#define USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID	BIT(22)
>> +#define USBSS_IRQ_MISC_ENABLE_SET_SESSVALID	BIT(20)
>> +
>> +/* IRQ_MISC_ENABLE_CLR register bits */
>> +#define USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID	BIT(22)
>> +#define USBSS_IRQ_MISC_ENABLE_CLR_SESSVALID	BIT(20)
>> +
>> +/* IRQ_MISC_EOI register bits */
>> +#define USBSS_IRQ_MISC_EOI_VECTOR	BIT(0)
>> +
>> +/* VBUS_STAT register bits */
>> +#define USBSS_VBUS_STAT_SESSVALID	BIT(2)
>> +#define USBSS_VBUS_STAT_VBUSVALID	BIT(0)
>> +
>> +/* Mask for PHY PLL REFCLK */
>> +#define PHY_PLL_REFCLK_MASK	GENMASK(3, 0)
>> +
>> +#define DWC3_AM62_AUTOSUSPEND_DELAY	100
>> +
>> +struct dwc3_data {
>> +	struct device *dev;
>> +	void __iomem *usbss;
>> +	struct clk *usb2_refclk;
>> +	struct work_struct work;
>> +	int vbus_irq;
>> +	int rate_code;
>> +	int connect;
>> +	struct regmap *syscon;
>> +	unsigned int offset;
>> +	unsigned int vbus_divider;
>> +};
>> +
>> +static const int dwc3_ti_rate_table[] = {	/* in KHZ */
>> +	9600,
>> +	10000,
>> +	12000,
>> +	19200,
>> +	20000,
>> +	24000,
>> +	25000,
>> +	26000,
>> +	38400,
>> +	40000,
>> +	58000,
>> +	50000,
>> +	52000,
>> +};
>> +
>> +static inline u32 dwc3_ti_readl(struct dwc3_data *data, u32 offset)
>> +{
>> +	return readl((data->usbss) + offset);
>> +}
>> +
>> +static inline void dwc3_ti_writel(struct dwc3_data *data, u32 offset, u32 value)
>> +{
>> +	writel(value, (data->usbss) + offset);
>> +}
>> +
>> +static void connect_detect_work(struct work_struct *work)
>> +{
>> +	struct dwc3_data *data =
>> +		container_of(work, struct dwc3_data, work);
>> +	u32 vbus_state, reg;
>> +	int connect = 0;
>> +
>> +	/* Read the status for VBUS valid register */
>> +	vbus_state = dwc3_ti_readl(data, USBSS_VBUS_STAT);
>> +	vbus_state &= USBSS_VBUS_STAT_VBUSVALID;
>> +
>> +	if (vbus_state)
>> +		connect = 1;
>> +
>> +	/* Set or clear mode valid bit based on connect or disconnect event */
>> +	if (data->connect != connect) {
>> +		reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
>> +		if (connect)
>> +			reg |= USBSS_MODE_VALID;
>> +		else
>> +			reg &= ~USBSS_MODE_VALID;
>> +
>> +		dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
>> +		data->connect = connect;
>> +	}
>> +}
>> +
>> +static irqreturn_t connect_detect_irq_handler(int irq, void *dev_id)
>> +{
>> +	struct dwc3_data *data = dev_id;
>> +	u32 reg;
>> +
>> +	/* Clear VBUS interrupt always to aviod queuing up redundant work items */
>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_STATUS);
>> +	reg |= USBSS_IRQ_MISC_VBUSVALID;
>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_STATUS, reg);
>> +
>> +	queue_work(system_power_efficient_wq, &data->work);
>> +
>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_EOI);
>> +	reg &= ~USBSS_IRQ_MISC_EOI_VECTOR;
>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_EOI, reg);
>> +	return IRQ_HANDLED;
>> +}
>> +
>> +static int dwc3_ti_vbus_irq_setup(struct platform_device *pdev)
>> +{
>> +	struct device *dev = &pdev->dev;
>> +	struct dwc3_data *data = platform_get_drvdata(pdev);
>> +	int irq, ret;
>> +
>> +	/* Get the misc interrupt */
>> +	irq = platform_get_irq(pdev, 0);
>> +	if (irq < 0)
>> +		return irq;
>> +
>> +	ret = devm_request_irq(dev, irq, connect_detect_irq_handler, IRQF_SHARED,
>> +			       dev_name(dev), data);
>> +	if (ret) {
>> +		dev_err(dev, "failed to required IRQ #%d-->%d\n",
>> +			irq, ret);
>> +		return ret;
>> +	}
>> +
>> +	data->vbus_irq = irq;
>> +
>> +	return 0;
>> +}
>> +
>> +static int phy_syscon_pll_refclk(struct dwc3_data *data)
>> +{
>> +	struct device *dev = data->dev;
>> +	struct device_node *node = dev->of_node;
>> +	struct of_phandle_args args;
>> +	struct regmap *syscon;
>> +	int ret;
>> +
>> +	syscon = syscon_regmap_lookup_by_phandle(node, "ti,syscon-phy-pll-refclk");
>> +	if (IS_ERR(syscon)) {
>> +		dev_err(dev, "unable to get ti,syscon-phy-pll-refclk regmap\n");
>> +		return PTR_ERR(syscon);
>> +	}
>> +
>> +	data->syscon = syscon;
>> +
>> +	ret = of_parse_phandle_with_fixed_args(node, "ti,syscon-phy-pll-refclk", 1,
>> +					       0, &args);
>> +	if (ret)
>> +		return ret;
>> +
>> +	data->offset = args.args[0];
>> +
>> +	ret = regmap_update_bits(data->syscon, data->offset, PHY_PLL_REFCLK_MASK, data->rate_code);
>> +	if (ret) {
>> +		dev_err(dev, "failed to set phy pll reference clock rate\n");
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static void dwc3_ti_enable_irqs(struct dwc3_data *data)
>> +{
>> +	u32 reg;
>> +
>> +	/* enable VBUSVALID interrupt */
>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_ENABLE_SET);
>> +	reg |= USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID;
>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_ENABLE_SET, reg);
>> +}
>> +
>> +static void dwc3_ti_disable_irqs(struct dwc3_data *data)
>> +{
>> +	u32 reg;
>> +
>> +	/* disable VBUSVALID interrupt */
>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_ENABLE_CLR);
>> +	reg |= USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID;
>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_ENABLE_CLR, reg);
>> +}
>> +
>> +static int dwc3_ti_probe(struct platform_device *pdev)
>> +{
>> +	struct device *dev = &pdev->dev;
>> +	struct device_node *node = pdev->dev.of_node;
>> +	struct dwc3_data *data;
>> +	int i, ret;
>> +	unsigned long rate;
>> +	u32 reg;
>> +
>> +	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
>> +	if (!data)
>> +		return -ENOMEM;
>> +
>> +	data->dev = dev;
>> +	platform_set_drvdata(pdev, data);
>> +
>> +	data->usbss = devm_platform_ioremap_resource(pdev, 0);
>> +	if (IS_ERR(data->usbss)) {
>> +		dev_err(dev, "can't map IOMEM resource\n");
>> +		return PTR_ERR(data->usbss);
>> +	}
>> +
>> +	data->usb2_refclk = devm_clk_get(dev, "ref");
>> +	if (IS_ERR(data->usb2_refclk)) {
>> +		dev_err(dev, "can't get usb2_refclk\n");
>> +		return PTR_ERR(data->usb2_refclk);
>> +	}
>> +
>> +	/* Calculate the rate code */
>> +	rate = clk_get_rate(data->usb2_refclk);
>> +	rate /= 1000;	// To KHz
>> +	for (i = 0; i < ARRAY_SIZE(dwc3_ti_rate_table); i++) {
>> +		if (dwc3_ti_rate_table[i] == rate)
>> +			break;
>> +	}
>> +
>> +	if (i == ARRAY_SIZE(dwc3_ti_rate_table)) {
>> +		dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate);
>> +		ret = -EINVAL;
>> +		goto err_clk_disable;
>> +	}
>> +
>> +	data->rate_code = i;
>> +
>> +	/* Read the syscon property and set the rate code */
>> +	ret = phy_syscon_pll_refclk(data);
>> +	if (ret)
>> +		goto err_clk_disable;
>> +
>> +	/* VBUS divider select */
>> +	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
>> +	reg = dwc3_ti_readl(data, USBSS_PHY_CONFIG);
>> +	if (data->vbus_divider)
>> +		reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT;
>> +
>> +	dwc3_ti_writel(data, USBSS_PHY_CONFIG, reg);
>> +
>> +	/* Initialize a work queue */
>> +	ret = devm_work_autocancel(dev, &data->work, connect_detect_work);
>> +	if (ret)
>> +		goto err_clk_disable;
>> +
>> +	/* Read and set VBUS IRQ */
>> +	ret = dwc3_ti_vbus_irq_setup(pdev);
>> +	if (ret)
>> +		goto err_clk_disable;
>> +
>> +	pm_runtime_set_active(dev);
>> +	pm_runtime_enable(dev);
>> +	/*
>> +	 * Don't ignore its dependencies with its children
>> +	 */
>> +	pm_suspend_ignore_children(dev, false);
>> +	clk_prepare_enable(data->usb2_refclk);
>> +	pm_runtime_get_noresume(dev);
>> +
>> +	ret = of_platform_populate(node, NULL, NULL, dev);
>> +	if (ret) {
>> +		dev_err(dev, "failed to create dwc3 core: %d\n", ret);
>> +		goto err_pm_disable;
>> +	}
>> +
>> +	/* Enable vbus irq */
>> +	dwc3_ti_enable_irqs(data);
>> +
>> +	connect_detect_work(&data->work);
>> +
>> +	/* Setting up autosuspend */
>> +	pm_runtime_set_autosuspend_delay(dev, DWC3_AM62_AUTOSUSPEND_DELAY);
>> +	pm_runtime_use_autosuspend(dev);
>> +	pm_runtime_mark_last_busy(dev);
>> +	pm_runtime_put_autosuspend(dev);
>> +	return 0;
>> +
>> +err_pm_disable:
>> +	clk_disable_unprepare(data->usb2_refclk);
>> +	pm_runtime_disable(dev);
>> +	pm_runtime_set_suspended(dev);
>> +err_clk_disable:
>> +	clk_put(data->usb2_refclk);
>> +	return ret;
>> +}
>> +
>> +static int dwc3_ti_remove_core(struct device *dev, void *c)
>> +{
>> +	struct platform_device *pdev = to_platform_device(dev);
>> +
>> +	platform_device_unregister(pdev);
>> +	return 0;
>> +}
>> +
>> +static int dwc3_ti_remove(struct platform_device *pdev)
>> +{
>> +	struct device *dev = &pdev->dev;
>> +	struct dwc3_data *data = platform_get_drvdata(pdev);
>> +	u32 reg;
>> +
>> +	dwc3_ti_disable_irqs(data);
>> +
>> +	device_for_each_child(dev, NULL, dwc3_ti_remove_core);
>> +
>> +	/* Clear mode valid bit */
>> +	reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
>> +	reg &= ~USBSS_MODE_VALID;
>> +	dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
>> +
>> +	pm_runtime_put_sync(dev);
>> +	clk_disable_unprepare(data->usb2_refclk);
>> +	pm_runtime_disable(dev);
>> +	pm_runtime_set_suspended(dev);
>> +
>> +	clk_put(data->usb2_refclk);
>> +	platform_set_drvdata(pdev, NULL);
>> +	return 0;
>> +}
>> +
>> +#ifdef CONFIG_PM
>> +static int dwc3_ti_suspend_common(struct device *dev)
>> +{
>> +	struct dwc3_data *data = dev_get_drvdata(dev);
>> +
>> +	/* disable irqs */
>> +	dwc3_ti_disable_irqs(data);
>> +
>> +	clk_disable_unprepare(data->usb2_refclk);
>> +
>> +	return 0;
>> +}
>> +
>> +static int dwc3_ti_resume_common(struct device *dev)
>> +{
>> +	struct dwc3_data *data = dev_get_drvdata(dev);
>> +
>> +	clk_prepare_enable(data->usb2_refclk);
>> +
>> +	/* Enable irqs */
>> +	dwc3_ti_enable_irqs(data);
>> +
>> +	return 0;
>> +}
>> +
>> +static UNIVERSAL_DEV_PM_OPS(dwc3_ti_pm_ops, dwc3_ti_suspend_common,
>> +			    dwc3_ti_resume_common, NULL);
>> +
>> +#define DEV_PM_OPS	(&dwc3_ti_pm_ops)
>> +#else
>> +#define DEV_PM_OPS	NULL
>> +#endif /* CONFIG_PM */
>> +
>> +static const struct of_device_id dwc3_ti_of_match[] = {
>> +	{ .compatible = "ti,am62-usb"},
>> +	{},
>> +};
>> +MODULE_DEVICE_TABLE(of, dwc3_ti_of_match);
>> +
>> +static struct platform_driver dwc3_ti_driver = {
>> +	.probe		= dwc3_ti_probe,
>> +	.remove		= dwc3_ti_remove,
>> +	.driver		= {
>> +		.name	= "dwc3-am62",
>> +		.pm	= DEV_PM_OPS,
>> +		.of_match_table = dwc3_ti_of_match,
>> +	},
>> +};
>> +
>> +module_platform_driver(dwc3_ti_driver);
>> +
>> +MODULE_ALIAS("platform:dwc3-am62");
>> +MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
>> +MODULE_LICENSE("GPL");
>> +MODULE_DESCRIPTION("DesignWare USB3 TI Glue Layer")

Re: [PATCH v3 2/2] drivers: usb: dwc3: Add AM62 USB wrapper driver

[Aswath Govindraju]

Hi Roger,

On 07/04/22 13:54, Aswath Govindraju wrote:
> Hi Roger,
> 
> On 07/04/22 13:50, Roger Quadros wrote:
>> Hi Aswath,
>>
>> On 06/04/2022 16:52, Aswath Govindraju wrote:
>>> In AM62 SoC, the Designware Core USB3 IP is progammed to operate in USB2.0
>>> only mode. Add driver for AM62 USB DWC3 Wrapper.
>>>
>>> Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
>>> ---
>>>
>>> changes since v2:
>>> - Removed the implementation of detecting the role from the wrapper
>>>   driver and moved the implementation to using linux,extcon-usb-gpio
>>>   driver for role detection.
>>
>> I'm a bit puzzled. So ID is managed by extcon-usb-gpio driver and
>> VBUS is managed by this driver.
>>
>> So who decides the USB ports state based on the below truth table?
>>
>> +	/*
>> +	 * ID | VBUS | STATE
>> +	 * -----------------
>> +	 * 0  | 0    | HOST
>> +	 * 0  | 1    | HOST
>> +	 * 1  | 0    | Disconnected (set mode valid to 0)
>> +	 * 1  | 1    | Device
>> +	 *
>> +	 */
>>
>> If only ID signal is available to extcon-usb-gpio driver it cannot detect
>> the Disconnected state. We need to set mode valid to 0 for disconnected state.
>>
> 
> Yes that is correct, the mode valid signal needs to be set when there is
> no cable connected. I am slightly confused on why 0-0 state is not
> considered disconnected? So, whenever VBUS is not high it should be
> disconnected right?
> 

Sorry, pressed the send button without reading everything properly.

The implementation is such that the extcon-usb-gpio only updates the
role to the core driver based on ID pin state and the Mode valid bit is
set by the wrapper based on the VBUS state.

Thanks,
Aswath

> Thanks,
> Aswath
> 
>> cheers,
>> -roger
>>
>>
>>> - Updated the binding documentation and example to reflect the same.
>>>
>>>
>>>  drivers/usb/dwc3/Kconfig     |   9 +
>>>  drivers/usb/dwc3/Makefile    |   1 +
>>>  drivers/usb/dwc3/dwc3-am62.c | 446 +++++++++++++++++++++++++++++++++++
>>>  3 files changed, 456 insertions(+)
>>>  create mode 100644 drivers/usb/dwc3/dwc3-am62.c
>>>
>>> diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
>>> index c483f28b695d..cd9a734522a7 100644
>>> --- a/drivers/usb/dwc3/Kconfig
>>> +++ b/drivers/usb/dwc3/Kconfig
>>> @@ -159,4 +159,13 @@ config USB_DWC3_XILINX
>>>  	  This driver handles both ZynqMP and Versal SoC operations.
>>>  	  Say 'Y' or 'M' if you have one such device.
>>>  
>>> +config USB_DWC3_AM62
>>> +	tristate "Texas Instruments AM62 Platforms"
>>> +	depends on ARCH_K3 || COMPILE_TEST
>>> +	default USB_DWC3
>>> +	help
>>> +	  Support TI's AM62 platforms with DesignWare Core USB3 IP.
>>> +	  The Designware Core USB3 IP is progammed to operate in
>>> +	  in USB 2.0 mode only.
>>> +	  Say 'Y' or 'M' here if you have one such device
>>>  endif
>>> diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
>>> index 2d499de6f66a..9f66bd82b639 100644
>>> --- a/drivers/usb/dwc3/Makefile
>>> +++ b/drivers/usb/dwc3/Makefile
>>> @@ -42,6 +42,7 @@ endif
>>>  # and allyesconfig builds.
>>>  ##
>>>  
>>> +obj-$(CONFIG_USB_DWC3_AM62)		+= dwc3-am62.o
>>>  obj-$(CONFIG_USB_DWC3_OMAP)		+= dwc3-omap.o
>>>  obj-$(CONFIG_USB_DWC3_EXYNOS)		+= dwc3-exynos.o
>>>  obj-$(CONFIG_USB_DWC3_PCI)		+= dwc3-pci.o
>>> diff --git a/drivers/usb/dwc3/dwc3-am62.c b/drivers/usb/dwc3/dwc3-am62.c
>>> new file mode 100644
>>> index 000000000000..5700258c8deb
>>> --- /dev/null
>>> +++ b/drivers/usb/dwc3/dwc3-am62.c
>>> @@ -0,0 +1,446 @@
>>> +// SPDX-License-Identifier: GPL-2.0
>>> +/*
>>> + * dwc3-am62.c - TI specific Glue layer for AM62 DWC3 USB Controller
>>> + *
>>> + * Copyright (C) 2022 Texas Instruments Incorporated - https://www.ti.com
>>> + */
>>> +
>>> +#include <linux/init.h>
>>> +#include <linux/interrupt.h>
>>> +#include <linux/irq.h>
>>> +#include <linux/kernel.h>
>>> +#include <linux/module.h>
>>> +#include <linux/platform_device.h>
>>> +#include <linux/workqueue.h>
>>> +#include <linux/mfd/syscon.h>
>>> +#include <linux/of.h>
>>> +#include <linux/of_device.h>
>>> +#include <linux/pm_runtime.h>
>>> +#include <linux/clk.h>
>>> +#include <linux/regmap.h>
>>> +#include <linux/devm-helpers.h>
>>> +#include <linux/pinctrl/consumer.h>
>>> +
>>> +/* USB WRAPPER register offsets */
>>> +#define USBSS_PID			0x0
>>> +#define USBSS_OVERCURRENT_CTRL		0x4
>>> +#define USBSS_PHY_CONFIG		0x8
>>> +#define USBSS_PHY_TEST			0xc
>>> +#define USBSS_CORE_STAT			0x14
>>> +#define USBSS_HOST_VBUS_CTRL		0x18
>>> +#define USBSS_MODE_CONTROL		0x1c
>>> +#define USBSS_WAKEUP_CONFIG		0x30
>>> +#define USBSS_WAKEUP_STAT		0x34
>>> +#define USBSS_OVERRIDE_CONFIG		0x38
>>> +#define USBSS_IRQ_MISC_STATUS_RAW	0x430
>>> +#define USBSS_IRQ_MISC_STATUS		0x434
>>> +#define USBSS_IRQ_MISC_ENABLE_SET	0x438
>>> +#define USBSS_IRQ_MISC_ENABLE_CLR	0x43c
>>> +#define USBSS_IRQ_MISC_EOI		0x440
>>> +#define USBSS_INTR_TEST			0x490
>>> +#define USBSS_VBUS_FILTER		0x614
>>> +#define USBSS_VBUS_STAT			0x618
>>> +#define USBSS_DEBUG_CFG			0x708
>>> +#define USBSS_DEBUG_DATA		0x70c
>>> +#define USBSS_HOST_HUB_CTRL		0x714
>>> +
>>> +/* PHY CONFIG register bits */
>>> +#define USBSS_PHY_VBUS_SEL_MASK		GENMASK(2, 1)
>>> +#define USBSS_PHY_VBUS_SEL_SHIFT	1
>>> +#define USBSS_PHY_LANE_REVERSE		BIT(0)
>>> +
>>> +/* MODE CONTROL register bits */
>>> +#define USBSS_MODE_VALID	BIT(0)
>>> +
>>> +/* WAKEUP CONFIG register bits */
>>> +#define USBSS_WAKEUP_CFG_OVERCURRENT_EN	BIT(3)
>>> +#define USBSS_WAKEUP_CFG_LINESTATE_EN	BIT(2)
>>> +#define USBSS_WAKEUP_CFG_SESSVALID_EN	BIT(1)
>>> +#define USBSS_WAKEUP_CFG_VBUSVALID_EN	BIT(0)
>>> +
>>> +/* WAKEUP STAT register bits */
>>> +#define USBSS_WAKEUP_STAT_OVERCURRENT	BIT(4)
>>> +#define USBSS_WAKEUP_STAT_LINESTATE	BIT(3)
>>> +#define USBSS_WAKEUP_STAT_SESSVALID	BIT(2)
>>> +#define USBSS_WAKEUP_STAT_VBUSVALID	BIT(1)
>>> +#define USBSS_WAKEUP_STAT_CLR		BIT(0)
>>> +
>>> +/* IRQ_MISC_STATUS_RAW register bits */
>>> +#define USBSS_IRQ_MISC_RAW_VBUSVALID	BIT(22)
>>> +#define USBSS_IRQ_MISC_RAW_SESSVALID	BIT(20)
>>> +
>>> +/* IRQ_MISC_STATUS register bits */
>>> +#define USBSS_IRQ_MISC_VBUSVALID	BIT(22)
>>> +#define USBSS_IRQ_MISC_SESSVALID	BIT(20)
>>> +
>>> +/* IRQ_MISC_ENABLE_SET register bits */
>>> +#define USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID	BIT(22)
>>> +#define USBSS_IRQ_MISC_ENABLE_SET_SESSVALID	BIT(20)
>>> +
>>> +/* IRQ_MISC_ENABLE_CLR register bits */
>>> +#define USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID	BIT(22)
>>> +#define USBSS_IRQ_MISC_ENABLE_CLR_SESSVALID	BIT(20)
>>> +
>>> +/* IRQ_MISC_EOI register bits */
>>> +#define USBSS_IRQ_MISC_EOI_VECTOR	BIT(0)
>>> +
>>> +/* VBUS_STAT register bits */
>>> +#define USBSS_VBUS_STAT_SESSVALID	BIT(2)
>>> +#define USBSS_VBUS_STAT_VBUSVALID	BIT(0)
>>> +
>>> +/* Mask for PHY PLL REFCLK */
>>> +#define PHY_PLL_REFCLK_MASK	GENMASK(3, 0)
>>> +
>>> +#define DWC3_AM62_AUTOSUSPEND_DELAY	100
>>> +
>>> +struct dwc3_data {
>>> +	struct device *dev;
>>> +	void __iomem *usbss;
>>> +	struct clk *usb2_refclk;
>>> +	struct work_struct work;
>>> +	int vbus_irq;
>>> +	int rate_code;
>>> +	int connect;
>>> +	struct regmap *syscon;
>>> +	unsigned int offset;
>>> +	unsigned int vbus_divider;
>>> +};
>>> +
>>> +static const int dwc3_ti_rate_table[] = {	/* in KHZ */
>>> +	9600,
>>> +	10000,
>>> +	12000,
>>> +	19200,
>>> +	20000,
>>> +	24000,
>>> +	25000,
>>> +	26000,
>>> +	38400,
>>> +	40000,
>>> +	58000,
>>> +	50000,
>>> +	52000,
>>> +};
>>> +
>>> +static inline u32 dwc3_ti_readl(struct dwc3_data *data, u32 offset)
>>> +{
>>> +	return readl((data->usbss) + offset);
>>> +}
>>> +
>>> +static inline void dwc3_ti_writel(struct dwc3_data *data, u32 offset, u32 value)
>>> +{
>>> +	writel(value, (data->usbss) + offset);
>>> +}
>>> +
>>> +static void connect_detect_work(struct work_struct *work)
>>> +{
>>> +	struct dwc3_data *data =
>>> +		container_of(work, struct dwc3_data, work);
>>> +	u32 vbus_state, reg;
>>> +	int connect = 0;
>>> +
>>> +	/* Read the status for VBUS valid register */
>>> +	vbus_state = dwc3_ti_readl(data, USBSS_VBUS_STAT);
>>> +	vbus_state &= USBSS_VBUS_STAT_VBUSVALID;
>>> +
>>> +	if (vbus_state)
>>> +		connect = 1;
>>> +
>>> +	/* Set or clear mode valid bit based on connect or disconnect event */
>>> +	if (data->connect != connect) {
>>> +		reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
>>> +		if (connect)
>>> +			reg |= USBSS_MODE_VALID;
>>> +		else
>>> +			reg &= ~USBSS_MODE_VALID;
>>> +
>>> +		dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
>>> +		data->connect = connect;
>>> +	}
>>> +}
>>> +
>>> +static irqreturn_t connect_detect_irq_handler(int irq, void *dev_id)
>>> +{
>>> +	struct dwc3_data *data = dev_id;
>>> +	u32 reg;
>>> +
>>> +	/* Clear VBUS interrupt always to aviod queuing up redundant work items */
>>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_STATUS);
>>> +	reg |= USBSS_IRQ_MISC_VBUSVALID;
>>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_STATUS, reg);
>>> +
>>> +	queue_work(system_power_efficient_wq, &data->work);
>>> +
>>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_EOI);
>>> +	reg &= ~USBSS_IRQ_MISC_EOI_VECTOR;
>>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_EOI, reg);
>>> +	return IRQ_HANDLED;
>>> +}
>>> +
>>> +static int dwc3_ti_vbus_irq_setup(struct platform_device *pdev)
>>> +{
>>> +	struct device *dev = &pdev->dev;
>>> +	struct dwc3_data *data = platform_get_drvdata(pdev);
>>> +	int irq, ret;
>>> +
>>> +	/* Get the misc interrupt */
>>> +	irq = platform_get_irq(pdev, 0);
>>> +	if (irq < 0)
>>> +		return irq;
>>> +
>>> +	ret = devm_request_irq(dev, irq, connect_detect_irq_handler, IRQF_SHARED,
>>> +			       dev_name(dev), data);
>>> +	if (ret) {
>>> +		dev_err(dev, "failed to required IRQ #%d-->%d\n",
>>> +			irq, ret);
>>> +		return ret;
>>> +	}
>>> +
>>> +	data->vbus_irq = irq;
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int phy_syscon_pll_refclk(struct dwc3_data *data)
>>> +{
>>> +	struct device *dev = data->dev;
>>> +	struct device_node *node = dev->of_node;
>>> +	struct of_phandle_args args;
>>> +	struct regmap *syscon;
>>> +	int ret;
>>> +
>>> +	syscon = syscon_regmap_lookup_by_phandle(node, "ti,syscon-phy-pll-refclk");
>>> +	if (IS_ERR(syscon)) {
>>> +		dev_err(dev, "unable to get ti,syscon-phy-pll-refclk regmap\n");
>>> +		return PTR_ERR(syscon);
>>> +	}
>>> +
>>> +	data->syscon = syscon;
>>> +
>>> +	ret = of_parse_phandle_with_fixed_args(node, "ti,syscon-phy-pll-refclk", 1,
>>> +					       0, &args);
>>> +	if (ret)
>>> +		return ret;
>>> +
>>> +	data->offset = args.args[0];
>>> +
>>> +	ret = regmap_update_bits(data->syscon, data->offset, PHY_PLL_REFCLK_MASK, data->rate_code);
>>> +	if (ret) {
>>> +		dev_err(dev, "failed to set phy pll reference clock rate\n");
>>> +		return ret;
>>> +	}
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static void dwc3_ti_enable_irqs(struct dwc3_data *data)
>>> +{
>>> +	u32 reg;
>>> +
>>> +	/* enable VBUSVALID interrupt */
>>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_ENABLE_SET);
>>> +	reg |= USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID;
>>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_ENABLE_SET, reg);
>>> +}
>>> +
>>> +static void dwc3_ti_disable_irqs(struct dwc3_data *data)
>>> +{
>>> +	u32 reg;
>>> +
>>> +	/* disable VBUSVALID interrupt */
>>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_ENABLE_CLR);
>>> +	reg |= USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID;
>>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_ENABLE_CLR, reg);
>>> +}
>>> +
>>> +static int dwc3_ti_probe(struct platform_device *pdev)
>>> +{
>>> +	struct device *dev = &pdev->dev;
>>> +	struct device_node *node = pdev->dev.of_node;
>>> +	struct dwc3_data *data;
>>> +	int i, ret;
>>> +	unsigned long rate;
>>> +	u32 reg;
>>> +
>>> +	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
>>> +	if (!data)
>>> +		return -ENOMEM;
>>> +
>>> +	data->dev = dev;
>>> +	platform_set_drvdata(pdev, data);
>>> +
>>> +	data->usbss = devm_platform_ioremap_resource(pdev, 0);
>>> +	if (IS_ERR(data->usbss)) {
>>> +		dev_err(dev, "can't map IOMEM resource\n");
>>> +		return PTR_ERR(data->usbss);
>>> +	}
>>> +
>>> +	data->usb2_refclk = devm_clk_get(dev, "ref");
>>> +	if (IS_ERR(data->usb2_refclk)) {
>>> +		dev_err(dev, "can't get usb2_refclk\n");
>>> +		return PTR_ERR(data->usb2_refclk);
>>> +	}
>>> +
>>> +	/* Calculate the rate code */
>>> +	rate = clk_get_rate(data->usb2_refclk);
>>> +	rate /= 1000;	// To KHz
>>> +	for (i = 0; i < ARRAY_SIZE(dwc3_ti_rate_table); i++) {
>>> +		if (dwc3_ti_rate_table[i] == rate)
>>> +			break;
>>> +	}
>>> +
>>> +	if (i == ARRAY_SIZE(dwc3_ti_rate_table)) {
>>> +		dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate);
>>> +		ret = -EINVAL;
>>> +		goto err_clk_disable;
>>> +	}
>>> +
>>> +	data->rate_code = i;
>>> +
>>> +	/* Read the syscon property and set the rate code */
>>> +	ret = phy_syscon_pll_refclk(data);
>>> +	if (ret)
>>> +		goto err_clk_disable;
>>> +
>>> +	/* VBUS divider select */
>>> +	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
>>> +	reg = dwc3_ti_readl(data, USBSS_PHY_CONFIG);
>>> +	if (data->vbus_divider)
>>> +		reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT;
>>> +
>>> +	dwc3_ti_writel(data, USBSS_PHY_CONFIG, reg);
>>> +
>>> +	/* Initialize a work queue */
>>> +	ret = devm_work_autocancel(dev, &data->work, connect_detect_work);
>>> +	if (ret)
>>> +		goto err_clk_disable;
>>> +
>>> +	/* Read and set VBUS IRQ */
>>> +	ret = dwc3_ti_vbus_irq_setup(pdev);
>>> +	if (ret)
>>> +		goto err_clk_disable;
>>> +
>>> +	pm_runtime_set_active(dev);
>>> +	pm_runtime_enable(dev);
>>> +	/*
>>> +	 * Don't ignore its dependencies with its children
>>> +	 */
>>> +	pm_suspend_ignore_children(dev, false);
>>> +	clk_prepare_enable(data->usb2_refclk);
>>> +	pm_runtime_get_noresume(dev);
>>> +
>>> +	ret = of_platform_populate(node, NULL, NULL, dev);
>>> +	if (ret) {
>>> +		dev_err(dev, "failed to create dwc3 core: %d\n", ret);
>>> +		goto err_pm_disable;
>>> +	}
>>> +
>>> +	/* Enable vbus irq */
>>> +	dwc3_ti_enable_irqs(data);
>>> +
>>> +	connect_detect_work(&data->work);
>>> +
>>> +	/* Setting up autosuspend */
>>> +	pm_runtime_set_autosuspend_delay(dev, DWC3_AM62_AUTOSUSPEND_DELAY);
>>> +	pm_runtime_use_autosuspend(dev);
>>> +	pm_runtime_mark_last_busy(dev);
>>> +	pm_runtime_put_autosuspend(dev);
>>> +	return 0;
>>> +
>>> +err_pm_disable:
>>> +	clk_disable_unprepare(data->usb2_refclk);
>>> +	pm_runtime_disable(dev);
>>> +	pm_runtime_set_suspended(dev);
>>> +err_clk_disable:
>>> +	clk_put(data->usb2_refclk);
>>> +	return ret;
>>> +}
>>> +
>>> +static int dwc3_ti_remove_core(struct device *dev, void *c)
>>> +{
>>> +	struct platform_device *pdev = to_platform_device(dev);
>>> +
>>> +	platform_device_unregister(pdev);
>>> +	return 0;
>>> +}
>>> +
>>> +static int dwc3_ti_remove(struct platform_device *pdev)
>>> +{
>>> +	struct device *dev = &pdev->dev;
>>> +	struct dwc3_data *data = platform_get_drvdata(pdev);
>>> +	u32 reg;
>>> +
>>> +	dwc3_ti_disable_irqs(data);
>>> +
>>> +	device_for_each_child(dev, NULL, dwc3_ti_remove_core);
>>> +
>>> +	/* Clear mode valid bit */
>>> +	reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
>>> +	reg &= ~USBSS_MODE_VALID;
>>> +	dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
>>> +
>>> +	pm_runtime_put_sync(dev);
>>> +	clk_disable_unprepare(data->usb2_refclk);
>>> +	pm_runtime_disable(dev);
>>> +	pm_runtime_set_suspended(dev);
>>> +
>>> +	clk_put(data->usb2_refclk);
>>> +	platform_set_drvdata(pdev, NULL);
>>> +	return 0;
>>> +}
>>> +
>>> +#ifdef CONFIG_PM
>>> +static int dwc3_ti_suspend_common(struct device *dev)
>>> +{
>>> +	struct dwc3_data *data = dev_get_drvdata(dev);
>>> +
>>> +	/* disable irqs */
>>> +	dwc3_ti_disable_irqs(data);
>>> +
>>> +	clk_disable_unprepare(data->usb2_refclk);
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int dwc3_ti_resume_common(struct device *dev)
>>> +{
>>> +	struct dwc3_data *data = dev_get_drvdata(dev);
>>> +
>>> +	clk_prepare_enable(data->usb2_refclk);
>>> +
>>> +	/* Enable irqs */
>>> +	dwc3_ti_enable_irqs(data);
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static UNIVERSAL_DEV_PM_OPS(dwc3_ti_pm_ops, dwc3_ti_suspend_common,
>>> +			    dwc3_ti_resume_common, NULL);
>>> +
>>> +#define DEV_PM_OPS	(&dwc3_ti_pm_ops)
>>> +#else
>>> +#define DEV_PM_OPS	NULL
>>> +#endif /* CONFIG_PM */
>>> +
>>> +static const struct of_device_id dwc3_ti_of_match[] = {
>>> +	{ .compatible = "ti,am62-usb"},
>>> +	{},
>>> +};
>>> +MODULE_DEVICE_TABLE(of, dwc3_ti_of_match);
>>> +
>>> +static struct platform_driver dwc3_ti_driver = {
>>> +	.probe		= dwc3_ti_probe,
>>> +	.remove		= dwc3_ti_remove,
>>> +	.driver		= {
>>> +		.name	= "dwc3-am62",
>>> +		.pm	= DEV_PM_OPS,
>>> +		.of_match_table = dwc3_ti_of_match,
>>> +	},
>>> +};
>>> +
>>> +module_platform_driver(dwc3_ti_driver);
>>> +
>>> +MODULE_ALIAS("platform:dwc3-am62");
>>> +MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
>>> +MODULE_LICENSE("GPL");
>>> +MODULE_DESCRIPTION("DesignWare USB3 TI Glue Layer")


-- 
Thanks,
Aswath

Re: [PATCH v3 2/2] drivers: usb: dwc3: Add AM62 USB wrapper driver

[Roger Quadros]

On 07/04/2022 11:27, Aswath Govindraju wrote:
> Hi Roger,
> 
> On 07/04/22 13:54, Aswath Govindraju wrote:
>> Hi Roger,
>>
>> On 07/04/22 13:50, Roger Quadros wrote:
>>> Hi Aswath,
>>>
>>> On 06/04/2022 16:52, Aswath Govindraju wrote:
>>>> In AM62 SoC, the Designware Core USB3 IP is progammed to operate in USB2.0
>>>> only mode. Add driver for AM62 USB DWC3 Wrapper.
>>>>
>>>> Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
>>>> ---
>>>>
>>>> changes since v2:
>>>> - Removed the implementation of detecting the role from the wrapper
>>>>   driver and moved the implementation to using linux,extcon-usb-gpio
>>>>   driver for role detection.
>>>
>>> I'm a bit puzzled. So ID is managed by extcon-usb-gpio driver and
>>> VBUS is managed by this driver.
>>>
>>> So who decides the USB ports state based on the below truth table?
>>>
>>> +	/*
>>> +	 * ID | VBUS | STATE
>>> +	 * -----------------
>>> +	 * 0  | 0    | HOST
>>> +	 * 0  | 1    | HOST
>>> +	 * 1  | 0    | Disconnected (set mode valid to 0)
>>> +	 * 1  | 1    | Device
>>> +	 *
>>> +	 */
>>>
>>> If only ID signal is available to extcon-usb-gpio driver it cannot detect
>>> the Disconnected state. We need to set mode valid to 0 for disconnected state.
>>>
>>
>> Yes that is correct, the mode valid signal needs to be set when there is
>> no cable connected. I am slightly confused on why 0-0 state is not
>> considered disconnected? So, whenever VBUS is not high it should be
>> disconnected right?

Not necessarily. We might be in host mode (ID=0) and just not turned on the VBUS regulator (VBUS=0).
Is this to be treated as disconnected?

I'm just pointing out that things won't function anymore like the below code you had earlier
as you have decoupled id_state from vbus_state.

+	/* detemine the role or find out if disconnect event */
+	if (id_state) {
+		detect_role = DEVICE;
+		if (vbus_state)
+			connect = 1;
+	} else {
+		detect_role = HOST;
+		connect = 1;
+	}

Now you are setting connect independently of ID. i.e. connect = vbus_state.

Is that what you want?

cheers,
-roger

>>
> 
> Sorry, pressed the send button without reading everything properly.
> 
> The implementation is such that the extcon-usb-gpio only updates the
> role to the core driver based on ID pin state and the Mode valid bit is
> set by the wrapper based on the VBUS state.
> 
> Thanks,
> Aswath
> 
>> Thanks,
>> Aswath
>>
>>> cheers,
>>> -roger
>>>
>>>
>>>> - Updated the binding documentation and example to reflect the same.
>>>>
>>>>
>>>>  drivers/usb/dwc3/Kconfig     |   9 +
>>>>  drivers/usb/dwc3/Makefile    |   1 +
>>>>  drivers/usb/dwc3/dwc3-am62.c | 446 +++++++++++++++++++++++++++++++++++
>>>>  3 files changed, 456 insertions(+)
>>>>  create mode 100644 drivers/usb/dwc3/dwc3-am62.c
>>>>
>>>> diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
>>>> index c483f28b695d..cd9a734522a7 100644
>>>> --- a/drivers/usb/dwc3/Kconfig
>>>> +++ b/drivers/usb/dwc3/Kconfig
>>>> @@ -159,4 +159,13 @@ config USB_DWC3_XILINX
>>>>  	  This driver handles both ZynqMP and Versal SoC operations.
>>>>  	  Say 'Y' or 'M' if you have one such device.
>>>>  
>>>> +config USB_DWC3_AM62
>>>> +	tristate "Texas Instruments AM62 Platforms"
>>>> +	depends on ARCH_K3 || COMPILE_TEST
>>>> +	default USB_DWC3
>>>> +	help
>>>> +	  Support TI's AM62 platforms with DesignWare Core USB3 IP.
>>>> +	  The Designware Core USB3 IP is progammed to operate in
>>>> +	  in USB 2.0 mode only.
>>>> +	  Say 'Y' or 'M' here if you have one such device
>>>>  endif
>>>> diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
>>>> index 2d499de6f66a..9f66bd82b639 100644
>>>> --- a/drivers/usb/dwc3/Makefile
>>>> +++ b/drivers/usb/dwc3/Makefile
>>>> @@ -42,6 +42,7 @@ endif
>>>>  # and allyesconfig builds.
>>>>  ##
>>>>  
>>>> +obj-$(CONFIG_USB_DWC3_AM62)		+= dwc3-am62.o
>>>>  obj-$(CONFIG_USB_DWC3_OMAP)		+= dwc3-omap.o
>>>>  obj-$(CONFIG_USB_DWC3_EXYNOS)		+= dwc3-exynos.o
>>>>  obj-$(CONFIG_USB_DWC3_PCI)		+= dwc3-pci.o
>>>> diff --git a/drivers/usb/dwc3/dwc3-am62.c b/drivers/usb/dwc3/dwc3-am62.c
>>>> new file mode 100644
>>>> index 000000000000..5700258c8deb
>>>> --- /dev/null
>>>> +++ b/drivers/usb/dwc3/dwc3-am62.c
>>>> @@ -0,0 +1,446 @@
>>>> +// SPDX-License-Identifier: GPL-2.0
>>>> +/*
>>>> + * dwc3-am62.c - TI specific Glue layer for AM62 DWC3 USB Controller
>>>> + *
>>>> + * Copyright (C) 2022 Texas Instruments Incorporated - https://www.ti.com
>>>> + */
>>>> +
>>>> +#include <linux/init.h>
>>>> +#include <linux/interrupt.h>
>>>> +#include <linux/irq.h>
>>>> +#include <linux/kernel.h>
>>>> +#include <linux/module.h>
>>>> +#include <linux/platform_device.h>
>>>> +#include <linux/workqueue.h>
>>>> +#include <linux/mfd/syscon.h>
>>>> +#include <linux/of.h>
>>>> +#include <linux/of_device.h>
>>>> +#include <linux/pm_runtime.h>
>>>> +#include <linux/clk.h>
>>>> +#include <linux/regmap.h>
>>>> +#include <linux/devm-helpers.h>
>>>> +#include <linux/pinctrl/consumer.h>
>>>> +
>>>> +/* USB WRAPPER register offsets */
>>>> +#define USBSS_PID			0x0
>>>> +#define USBSS_OVERCURRENT_CTRL		0x4
>>>> +#define USBSS_PHY_CONFIG		0x8
>>>> +#define USBSS_PHY_TEST			0xc
>>>> +#define USBSS_CORE_STAT			0x14
>>>> +#define USBSS_HOST_VBUS_CTRL		0x18
>>>> +#define USBSS_MODE_CONTROL		0x1c
>>>> +#define USBSS_WAKEUP_CONFIG		0x30
>>>> +#define USBSS_WAKEUP_STAT		0x34
>>>> +#define USBSS_OVERRIDE_CONFIG		0x38
>>>> +#define USBSS_IRQ_MISC_STATUS_RAW	0x430
>>>> +#define USBSS_IRQ_MISC_STATUS		0x434
>>>> +#define USBSS_IRQ_MISC_ENABLE_SET	0x438
>>>> +#define USBSS_IRQ_MISC_ENABLE_CLR	0x43c
>>>> +#define USBSS_IRQ_MISC_EOI		0x440
>>>> +#define USBSS_INTR_TEST			0x490
>>>> +#define USBSS_VBUS_FILTER		0x614
>>>> +#define USBSS_VBUS_STAT			0x618
>>>> +#define USBSS_DEBUG_CFG			0x708
>>>> +#define USBSS_DEBUG_DATA		0x70c
>>>> +#define USBSS_HOST_HUB_CTRL		0x714
>>>> +
>>>> +/* PHY CONFIG register bits */
>>>> +#define USBSS_PHY_VBUS_SEL_MASK		GENMASK(2, 1)
>>>> +#define USBSS_PHY_VBUS_SEL_SHIFT	1
>>>> +#define USBSS_PHY_LANE_REVERSE		BIT(0)
>>>> +
>>>> +/* MODE CONTROL register bits */
>>>> +#define USBSS_MODE_VALID	BIT(0)
>>>> +
>>>> +/* WAKEUP CONFIG register bits */
>>>> +#define USBSS_WAKEUP_CFG_OVERCURRENT_EN	BIT(3)
>>>> +#define USBSS_WAKEUP_CFG_LINESTATE_EN	BIT(2)
>>>> +#define USBSS_WAKEUP_CFG_SESSVALID_EN	BIT(1)
>>>> +#define USBSS_WAKEUP_CFG_VBUSVALID_EN	BIT(0)
>>>> +
>>>> +/* WAKEUP STAT register bits */
>>>> +#define USBSS_WAKEUP_STAT_OVERCURRENT	BIT(4)
>>>> +#define USBSS_WAKEUP_STAT_LINESTATE	BIT(3)
>>>> +#define USBSS_WAKEUP_STAT_SESSVALID	BIT(2)
>>>> +#define USBSS_WAKEUP_STAT_VBUSVALID	BIT(1)
>>>> +#define USBSS_WAKEUP_STAT_CLR		BIT(0)
>>>> +
>>>> +/* IRQ_MISC_STATUS_RAW register bits */
>>>> +#define USBSS_IRQ_MISC_RAW_VBUSVALID	BIT(22)
>>>> +#define USBSS_IRQ_MISC_RAW_SESSVALID	BIT(20)
>>>> +
>>>> +/* IRQ_MISC_STATUS register bits */
>>>> +#define USBSS_IRQ_MISC_VBUSVALID	BIT(22)
>>>> +#define USBSS_IRQ_MISC_SESSVALID	BIT(20)
>>>> +
>>>> +/* IRQ_MISC_ENABLE_SET register bits */
>>>> +#define USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID	BIT(22)
>>>> +#define USBSS_IRQ_MISC_ENABLE_SET_SESSVALID	BIT(20)
>>>> +
>>>> +/* IRQ_MISC_ENABLE_CLR register bits */
>>>> +#define USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID	BIT(22)
>>>> +#define USBSS_IRQ_MISC_ENABLE_CLR_SESSVALID	BIT(20)
>>>> +
>>>> +/* IRQ_MISC_EOI register bits */
>>>> +#define USBSS_IRQ_MISC_EOI_VECTOR	BIT(0)
>>>> +
>>>> +/* VBUS_STAT register bits */
>>>> +#define USBSS_VBUS_STAT_SESSVALID	BIT(2)
>>>> +#define USBSS_VBUS_STAT_VBUSVALID	BIT(0)
>>>> +
>>>> +/* Mask for PHY PLL REFCLK */
>>>> +#define PHY_PLL_REFCLK_MASK	GENMASK(3, 0)
>>>> +
>>>> +#define DWC3_AM62_AUTOSUSPEND_DELAY	100
>>>> +
>>>> +struct dwc3_data {
>>>> +	struct device *dev;
>>>> +	void __iomem *usbss;
>>>> +	struct clk *usb2_refclk;
>>>> +	struct work_struct work;
>>>> +	int vbus_irq;
>>>> +	int rate_code;
>>>> +	int connect;
>>>> +	struct regmap *syscon;
>>>> +	unsigned int offset;
>>>> +	unsigned int vbus_divider;
>>>> +};
>>>> +
>>>> +static const int dwc3_ti_rate_table[] = {	/* in KHZ */
>>>> +	9600,
>>>> +	10000,
>>>> +	12000,
>>>> +	19200,
>>>> +	20000,
>>>> +	24000,
>>>> +	25000,
>>>> +	26000,
>>>> +	38400,
>>>> +	40000,
>>>> +	58000,
>>>> +	50000,
>>>> +	52000,
>>>> +};
>>>> +
>>>> +static inline u32 dwc3_ti_readl(struct dwc3_data *data, u32 offset)
>>>> +{
>>>> +	return readl((data->usbss) + offset);
>>>> +}
>>>> +
>>>> +static inline void dwc3_ti_writel(struct dwc3_data *data, u32 offset, u32 value)
>>>> +{
>>>> +	writel(value, (data->usbss) + offset);
>>>> +}
>>>> +
>>>> +static void connect_detect_work(struct work_struct *work)
>>>> +{
>>>> +	struct dwc3_data *data =
>>>> +		container_of(work, struct dwc3_data, work);
>>>> +	u32 vbus_state, reg;
>>>> +	int connect = 0;
>>>> +
>>>> +	/* Read the status for VBUS valid register */
>>>> +	vbus_state = dwc3_ti_readl(data, USBSS_VBUS_STAT);
>>>> +	vbus_state &= USBSS_VBUS_STAT_VBUSVALID;
>>>> +
>>>> +	if (vbus_state)
>>>> +		connect = 1;
>>>> +
>>>> +	/* Set or clear mode valid bit based on connect or disconnect event */
>>>> +	if (data->connect != connect) {
>>>> +		reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
>>>> +		if (connect)
>>>> +			reg |= USBSS_MODE_VALID;
>>>> +		else
>>>> +			reg &= ~USBSS_MODE_VALID;
>>>> +
>>>> +		dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
>>>> +		data->connect = connect;
>>>> +	}
>>>> +}
>>>> +
>>>> +static irqreturn_t connect_detect_irq_handler(int irq, void *dev_id)
>>>> +{
>>>> +	struct dwc3_data *data = dev_id;
>>>> +	u32 reg;
>>>> +
>>>> +	/* Clear VBUS interrupt always to aviod queuing up redundant work items */
>>>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_STATUS);
>>>> +	reg |= USBSS_IRQ_MISC_VBUSVALID;
>>>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_STATUS, reg);
>>>> +
>>>> +	queue_work(system_power_efficient_wq, &data->work);
>>>> +
>>>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_EOI);
>>>> +	reg &= ~USBSS_IRQ_MISC_EOI_VECTOR;
>>>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_EOI, reg);
>>>> +	return IRQ_HANDLED;
>>>> +}
>>>> +
>>>> +static int dwc3_ti_vbus_irq_setup(struct platform_device *pdev)
>>>> +{
>>>> +	struct device *dev = &pdev->dev;
>>>> +	struct dwc3_data *data = platform_get_drvdata(pdev);
>>>> +	int irq, ret;
>>>> +
>>>> +	/* Get the misc interrupt */
>>>> +	irq = platform_get_irq(pdev, 0);
>>>> +	if (irq < 0)
>>>> +		return irq;
>>>> +
>>>> +	ret = devm_request_irq(dev, irq, connect_detect_irq_handler, IRQF_SHARED,
>>>> +			       dev_name(dev), data);
>>>> +	if (ret) {
>>>> +		dev_err(dev, "failed to required IRQ #%d-->%d\n",
>>>> +			irq, ret);
>>>> +		return ret;
>>>> +	}
>>>> +
>>>> +	data->vbus_irq = irq;
>>>> +
>>>> +	return 0;
>>>> +}
>>>> +
>>>> +static int phy_syscon_pll_refclk(struct dwc3_data *data)
>>>> +{
>>>> +	struct device *dev = data->dev;
>>>> +	struct device_node *node = dev->of_node;
>>>> +	struct of_phandle_args args;
>>>> +	struct regmap *syscon;
>>>> +	int ret;
>>>> +
>>>> +	syscon = syscon_regmap_lookup_by_phandle(node, "ti,syscon-phy-pll-refclk");
>>>> +	if (IS_ERR(syscon)) {
>>>> +		dev_err(dev, "unable to get ti,syscon-phy-pll-refclk regmap\n");
>>>> +		return PTR_ERR(syscon);
>>>> +	}
>>>> +
>>>> +	data->syscon = syscon;
>>>> +
>>>> +	ret = of_parse_phandle_with_fixed_args(node, "ti,syscon-phy-pll-refclk", 1,
>>>> +					       0, &args);
>>>> +	if (ret)
>>>> +		return ret;
>>>> +
>>>> +	data->offset = args.args[0];
>>>> +
>>>> +	ret = regmap_update_bits(data->syscon, data->offset, PHY_PLL_REFCLK_MASK, data->rate_code);
>>>> +	if (ret) {
>>>> +		dev_err(dev, "failed to set phy pll reference clock rate\n");
>>>> +		return ret;
>>>> +	}
>>>> +
>>>> +	return 0;
>>>> +}
>>>> +
>>>> +static void dwc3_ti_enable_irqs(struct dwc3_data *data)
>>>> +{
>>>> +	u32 reg;
>>>> +
>>>> +	/* enable VBUSVALID interrupt */
>>>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_ENABLE_SET);
>>>> +	reg |= USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID;
>>>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_ENABLE_SET, reg);
>>>> +}
>>>> +
>>>> +static void dwc3_ti_disable_irqs(struct dwc3_data *data)
>>>> +{
>>>> +	u32 reg;
>>>> +
>>>> +	/* disable VBUSVALID interrupt */
>>>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_ENABLE_CLR);
>>>> +	reg |= USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID;
>>>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_ENABLE_CLR, reg);
>>>> +}
>>>> +
>>>> +static int dwc3_ti_probe(struct platform_device *pdev)
>>>> +{
>>>> +	struct device *dev = &pdev->dev;
>>>> +	struct device_node *node = pdev->dev.of_node;
>>>> +	struct dwc3_data *data;
>>>> +	int i, ret;
>>>> +	unsigned long rate;
>>>> +	u32 reg;
>>>> +
>>>> +	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
>>>> +	if (!data)
>>>> +		return -ENOMEM;
>>>> +
>>>> +	data->dev = dev;
>>>> +	platform_set_drvdata(pdev, data);
>>>> +
>>>> +	data->usbss = devm_platform_ioremap_resource(pdev, 0);
>>>> +	if (IS_ERR(data->usbss)) {
>>>> +		dev_err(dev, "can't map IOMEM resource\n");
>>>> +		return PTR_ERR(data->usbss);
>>>> +	}
>>>> +
>>>> +	data->usb2_refclk = devm_clk_get(dev, "ref");
>>>> +	if (IS_ERR(data->usb2_refclk)) {
>>>> +		dev_err(dev, "can't get usb2_refclk\n");
>>>> +		return PTR_ERR(data->usb2_refclk);
>>>> +	}
>>>> +
>>>> +	/* Calculate the rate code */
>>>> +	rate = clk_get_rate(data->usb2_refclk);
>>>> +	rate /= 1000;	// To KHz
>>>> +	for (i = 0; i < ARRAY_SIZE(dwc3_ti_rate_table); i++) {
>>>> +		if (dwc3_ti_rate_table[i] == rate)
>>>> +			break;
>>>> +	}
>>>> +
>>>> +	if (i == ARRAY_SIZE(dwc3_ti_rate_table)) {
>>>> +		dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate);
>>>> +		ret = -EINVAL;
>>>> +		goto err_clk_disable;
>>>> +	}
>>>> +
>>>> +	data->rate_code = i;
>>>> +
>>>> +	/* Read the syscon property and set the rate code */
>>>> +	ret = phy_syscon_pll_refclk(data);
>>>> +	if (ret)
>>>> +		goto err_clk_disable;
>>>> +
>>>> +	/* VBUS divider select */
>>>> +	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
>>>> +	reg = dwc3_ti_readl(data, USBSS_PHY_CONFIG);
>>>> +	if (data->vbus_divider)
>>>> +		reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT;
>>>> +
>>>> +	dwc3_ti_writel(data, USBSS_PHY_CONFIG, reg);
>>>> +
>>>> +	/* Initialize a work queue */
>>>> +	ret = devm_work_autocancel(dev, &data->work, connect_detect_work);
>>>> +	if (ret)
>>>> +		goto err_clk_disable;
>>>> +
>>>> +	/* Read and set VBUS IRQ */
>>>> +	ret = dwc3_ti_vbus_irq_setup(pdev);
>>>> +	if (ret)
>>>> +		goto err_clk_disable;
>>>> +
>>>> +	pm_runtime_set_active(dev);
>>>> +	pm_runtime_enable(dev);
>>>> +	/*
>>>> +	 * Don't ignore its dependencies with its children
>>>> +	 */
>>>> +	pm_suspend_ignore_children(dev, false);
>>>> +	clk_prepare_enable(data->usb2_refclk);
>>>> +	pm_runtime_get_noresume(dev);
>>>> +
>>>> +	ret = of_platform_populate(node, NULL, NULL, dev);
>>>> +	if (ret) {
>>>> +		dev_err(dev, "failed to create dwc3 core: %d\n", ret);
>>>> +		goto err_pm_disable;
>>>> +	}
>>>> +
>>>> +	/* Enable vbus irq */
>>>> +	dwc3_ti_enable_irqs(data);
>>>> +
>>>> +	connect_detect_work(&data->work);
>>>> +
>>>> +	/* Setting up autosuspend */
>>>> +	pm_runtime_set_autosuspend_delay(dev, DWC3_AM62_AUTOSUSPEND_DELAY);
>>>> +	pm_runtime_use_autosuspend(dev);
>>>> +	pm_runtime_mark_last_busy(dev);
>>>> +	pm_runtime_put_autosuspend(dev);
>>>> +	return 0;
>>>> +
>>>> +err_pm_disable:
>>>> +	clk_disable_unprepare(data->usb2_refclk);
>>>> +	pm_runtime_disable(dev);
>>>> +	pm_runtime_set_suspended(dev);
>>>> +err_clk_disable:
>>>> +	clk_put(data->usb2_refclk);
>>>> +	return ret;
>>>> +}
>>>> +
>>>> +static int dwc3_ti_remove_core(struct device *dev, void *c)
>>>> +{
>>>> +	struct platform_device *pdev = to_platform_device(dev);
>>>> +
>>>> +	platform_device_unregister(pdev);
>>>> +	return 0;
>>>> +}
>>>> +
>>>> +static int dwc3_ti_remove(struct platform_device *pdev)
>>>> +{
>>>> +	struct device *dev = &pdev->dev;
>>>> +	struct dwc3_data *data = platform_get_drvdata(pdev);
>>>> +	u32 reg;
>>>> +
>>>> +	dwc3_ti_disable_irqs(data);
>>>> +
>>>> +	device_for_each_child(dev, NULL, dwc3_ti_remove_core);
>>>> +
>>>> +	/* Clear mode valid bit */
>>>> +	reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
>>>> +	reg &= ~USBSS_MODE_VALID;
>>>> +	dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
>>>> +
>>>> +	pm_runtime_put_sync(dev);
>>>> +	clk_disable_unprepare(data->usb2_refclk);
>>>> +	pm_runtime_disable(dev);
>>>> +	pm_runtime_set_suspended(dev);
>>>> +
>>>> +	clk_put(data->usb2_refclk);
>>>> +	platform_set_drvdata(pdev, NULL);
>>>> +	return 0;
>>>> +}
>>>> +
>>>> +#ifdef CONFIG_PM
>>>> +static int dwc3_ti_suspend_common(struct device *dev)
>>>> +{
>>>> +	struct dwc3_data *data = dev_get_drvdata(dev);
>>>> +
>>>> +	/* disable irqs */
>>>> +	dwc3_ti_disable_irqs(data);
>>>> +
>>>> +	clk_disable_unprepare(data->usb2_refclk);
>>>> +
>>>> +	return 0;
>>>> +}
>>>> +
>>>> +static int dwc3_ti_resume_common(struct device *dev)
>>>> +{
>>>> +	struct dwc3_data *data = dev_get_drvdata(dev);
>>>> +
>>>> +	clk_prepare_enable(data->usb2_refclk);
>>>> +
>>>> +	/* Enable irqs */
>>>> +	dwc3_ti_enable_irqs(data);
>>>> +
>>>> +	return 0;
>>>> +}
>>>> +
>>>> +static UNIVERSAL_DEV_PM_OPS(dwc3_ti_pm_ops, dwc3_ti_suspend_common,
>>>> +			    dwc3_ti_resume_common, NULL);
>>>> +
>>>> +#define DEV_PM_OPS	(&dwc3_ti_pm_ops)
>>>> +#else
>>>> +#define DEV_PM_OPS	NULL
>>>> +#endif /* CONFIG_PM */
>>>> +
>>>> +static const struct of_device_id dwc3_ti_of_match[] = {
>>>> +	{ .compatible = "ti,am62-usb"},
>>>> +	{},
>>>> +};
>>>> +MODULE_DEVICE_TABLE(of, dwc3_ti_of_match);
>>>> +
>>>> +static struct platform_driver dwc3_ti_driver = {
>>>> +	.probe		= dwc3_ti_probe,
>>>> +	.remove		= dwc3_ti_remove,
>>>> +	.driver		= {
>>>> +		.name	= "dwc3-am62",
>>>> +		.pm	= DEV_PM_OPS,
>>>> +		.of_match_table = dwc3_ti_of_match,
>>>> +	},
>>>> +};
>>>> +
>>>> +module_platform_driver(dwc3_ti_driver);
>>>> +
>>>> +MODULE_ALIAS("platform:dwc3-am62");
>>>> +MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
>>>> +MODULE_LICENSE("GPL");
>>>> +MODULE_DESCRIPTION("DesignWare USB3 TI Glue Layer")
> 
> 

Re: [PATCH v3 2/2] drivers: usb: dwc3: Add AM62 USB wrapper driver

[Aswath Govindraju]

Hi Roger,

On 07/04/22 14:24, Roger Quadros wrote:
> 
> 
> On 07/04/2022 11:27, Aswath Govindraju wrote:
>> Hi Roger,
>>
>> On 07/04/22 13:54, Aswath Govindraju wrote:
>>> Hi Roger,
>>>
>>> On 07/04/22 13:50, Roger Quadros wrote:
>>>> Hi Aswath,
>>>>
>>>> On 06/04/2022 16:52, Aswath Govindraju wrote:
>>>>> In AM62 SoC, the Designware Core USB3 IP is progammed to operate in USB2.0
>>>>> only mode. Add driver for AM62 USB DWC3 Wrapper.
>>>>>
>>>>> Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
>>>>> ---
>>>>>
>>>>> changes since v2:
>>>>> - Removed the implementation of detecting the role from the wrapper
>>>>>   driver and moved the implementation to using linux,extcon-usb-gpio
>>>>>   driver for role detection.
>>>>
>>>> I'm a bit puzzled. So ID is managed by extcon-usb-gpio driver and
>>>> VBUS is managed by this driver.
>>>>
>>>> So who decides the USB ports state based on the below truth table?
>>>>
>>>> +	/*
>>>> +	 * ID | VBUS | STATE
>>>> +	 * -----------------
>>>> +	 * 0  | 0    | HOST
>>>> +	 * 0  | 1    | HOST
>>>> +	 * 1  | 0    | Disconnected (set mode valid to 0)
>>>> +	 * 1  | 1    | Device
>>>> +	 *
>>>> +	 */
>>>>
>>>> If only ID signal is available to extcon-usb-gpio driver it cannot detect
>>>> the Disconnected state. We need to set mode valid to 0 for disconnected state.
>>>>
>>>
>>> Yes that is correct, the mode valid signal needs to be set when there is
>>> no cable connected. I am slightly confused on why 0-0 state is not
>>> considered disconnected? So, whenever VBUS is not high it should be
>>> disconnected right?
> 
> Not necessarily. We might be in host mode (ID=0) and just not turned on the VBUS regulator (VBUS=0).
> Is this to be treated as disconnected?
> 

This should be treated as disconnected state right? Since the device is
not essentially connected to host and only after VBUS is supplied from
the host, the device starts to enumerate.

The controller will move to host mode but the devices will not get
enumerated. The device will get enumerated only after we supply VBUS and
this event will be registered and mode valid bit will be set.


> I'm just pointing out that things won't function anymore like the below code you had earlier
> as you have decoupled id_state from vbus_state.
> 
> +	/* detemine the role or find out if disconnect event */
> +	if (id_state) {
> +		detect_role = DEVICE;
> +		if (vbus_state)
> +			connect = 1;
> +	} else {
> +		detect_role = HOST;
> +		connect = 1;
> +	}
> 
> Now you are setting connect independently of ID. i.e. connect = vbus_state.
> 
> Is that what you want?
> 

Yes, I changed it as I felt that the dependency can be removed.

Thanks,
Aswath

> cheers,
> -roger
> 
>>>
>>
>> Sorry, pressed the send button without reading everything properly.
>>
>> The implementation is such that the extcon-usb-gpio only updates the
>> role to the core driver based on ID pin state and the Mode valid bit is
>> set by the wrapper based on the VBUS state.
>>
>> Thanks,
>> Aswath
>>
>>> Thanks,
>>> Aswath
>>>
>>>> cheers,
>>>> -roger
>>>>
>>>>
>>>>> - Updated the binding documentation and example to reflect the same.
>>>>>
>>>>>
>>>>>  drivers/usb/dwc3/Kconfig     |   9 +
>>>>>  drivers/usb/dwc3/Makefile    |   1 +
>>>>>  drivers/usb/dwc3/dwc3-am62.c | 446 +++++++++++++++++++++++++++++++++++
>>>>>  3 files changed, 456 insertions(+)
>>>>>  create mode 100644 drivers/usb/dwc3/dwc3-am62.c
>>>>>
>>>>> diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
>>>>> index c483f28b695d..cd9a734522a7 100644
>>>>> --- a/drivers/usb/dwc3/Kconfig
>>>>> +++ b/drivers/usb/dwc3/Kconfig
>>>>> @@ -159,4 +159,13 @@ config USB_DWC3_XILINX
>>>>>  	  This driver handles both ZynqMP and Versal SoC operations.
>>>>>  	  Say 'Y' or 'M' if you have one such device.
>>>>>  
>>>>> +config USB_DWC3_AM62
>>>>> +	tristate "Texas Instruments AM62 Platforms"
>>>>> +	depends on ARCH_K3 || COMPILE_TEST
>>>>> +	default USB_DWC3
>>>>> +	help
>>>>> +	  Support TI's AM62 platforms with DesignWare Core USB3 IP.
>>>>> +	  The Designware Core USB3 IP is progammed to operate in
>>>>> +	  in USB 2.0 mode only.
>>>>> +	  Say 'Y' or 'M' here if you have one such device
>>>>>  endif
>>>>> diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
>>>>> index 2d499de6f66a..9f66bd82b639 100644
>>>>> --- a/drivers/usb/dwc3/Makefile
>>>>> +++ b/drivers/usb/dwc3/Makefile
>>>>> @@ -42,6 +42,7 @@ endif
>>>>>  # and allyesconfig builds.
>>>>>  ##
>>>>>  
>>>>> +obj-$(CONFIG_USB_DWC3_AM62)		+= dwc3-am62.o
>>>>>  obj-$(CONFIG_USB_DWC3_OMAP)		+= dwc3-omap.o
>>>>>  obj-$(CONFIG_USB_DWC3_EXYNOS)		+= dwc3-exynos.o
>>>>>  obj-$(CONFIG_USB_DWC3_PCI)		+= dwc3-pci.o
>>>>> diff --git a/drivers/usb/dwc3/dwc3-am62.c b/drivers/usb/dwc3/dwc3-am62.c
>>>>> new file mode 100644
>>>>> index 000000000000..5700258c8deb
>>>>> --- /dev/null
>>>>> +++ b/drivers/usb/dwc3/dwc3-am62.c
>>>>> @@ -0,0 +1,446 @@
>>>>> +// SPDX-License-Identifier: GPL-2.0
>>>>> +/*
>>>>> + * dwc3-am62.c - TI specific Glue layer for AM62 DWC3 USB Controller
>>>>> + *
>>>>> + * Copyright (C) 2022 Texas Instruments Incorporated - https://www.ti.com
>>>>> + */
>>>>> +
>>>>> +#include <linux/init.h>
>>>>> +#include <linux/interrupt.h>
>>>>> +#include <linux/irq.h>
>>>>> +#include <linux/kernel.h>
>>>>> +#include <linux/module.h>
>>>>> +#include <linux/platform_device.h>
>>>>> +#include <linux/workqueue.h>
>>>>> +#include <linux/mfd/syscon.h>
>>>>> +#include <linux/of.h>
>>>>> +#include <linux/of_device.h>
>>>>> +#include <linux/pm_runtime.h>
>>>>> +#include <linux/clk.h>
>>>>> +#include <linux/regmap.h>
>>>>> +#include <linux/devm-helpers.h>
>>>>> +#include <linux/pinctrl/consumer.h>
>>>>> +
>>>>> +/* USB WRAPPER register offsets */
>>>>> +#define USBSS_PID			0x0
>>>>> +#define USBSS_OVERCURRENT_CTRL		0x4
>>>>> +#define USBSS_PHY_CONFIG		0x8
>>>>> +#define USBSS_PHY_TEST			0xc
>>>>> +#define USBSS_CORE_STAT			0x14
>>>>> +#define USBSS_HOST_VBUS_CTRL		0x18
>>>>> +#define USBSS_MODE_CONTROL		0x1c
>>>>> +#define USBSS_WAKEUP_CONFIG		0x30
>>>>> +#define USBSS_WAKEUP_STAT		0x34
>>>>> +#define USBSS_OVERRIDE_CONFIG		0x38
>>>>> +#define USBSS_IRQ_MISC_STATUS_RAW	0x430
>>>>> +#define USBSS_IRQ_MISC_STATUS		0x434
>>>>> +#define USBSS_IRQ_MISC_ENABLE_SET	0x438
>>>>> +#define USBSS_IRQ_MISC_ENABLE_CLR	0x43c
>>>>> +#define USBSS_IRQ_MISC_EOI		0x440
>>>>> +#define USBSS_INTR_TEST			0x490
>>>>> +#define USBSS_VBUS_FILTER		0x614
>>>>> +#define USBSS_VBUS_STAT			0x618
>>>>> +#define USBSS_DEBUG_CFG			0x708
>>>>> +#define USBSS_DEBUG_DATA		0x70c
>>>>> +#define USBSS_HOST_HUB_CTRL		0x714
>>>>> +
>>>>> +/* PHY CONFIG register bits */
>>>>> +#define USBSS_PHY_VBUS_SEL_MASK		GENMASK(2, 1)
>>>>> +#define USBSS_PHY_VBUS_SEL_SHIFT	1
>>>>> +#define USBSS_PHY_LANE_REVERSE		BIT(0)
>>>>> +
>>>>> +/* MODE CONTROL register bits */
>>>>> +#define USBSS_MODE_VALID	BIT(0)
>>>>> +
>>>>> +/* WAKEUP CONFIG register bits */
>>>>> +#define USBSS_WAKEUP_CFG_OVERCURRENT_EN	BIT(3)
>>>>> +#define USBSS_WAKEUP_CFG_LINESTATE_EN	BIT(2)
>>>>> +#define USBSS_WAKEUP_CFG_SESSVALID_EN	BIT(1)
>>>>> +#define USBSS_WAKEUP_CFG_VBUSVALID_EN	BIT(0)
>>>>> +
>>>>> +/* WAKEUP STAT register bits */
>>>>> +#define USBSS_WAKEUP_STAT_OVERCURRENT	BIT(4)
>>>>> +#define USBSS_WAKEUP_STAT_LINESTATE	BIT(3)
>>>>> +#define USBSS_WAKEUP_STAT_SESSVALID	BIT(2)
>>>>> +#define USBSS_WAKEUP_STAT_VBUSVALID	BIT(1)
>>>>> +#define USBSS_WAKEUP_STAT_CLR		BIT(0)
>>>>> +
>>>>> +/* IRQ_MISC_STATUS_RAW register bits */
>>>>> +#define USBSS_IRQ_MISC_RAW_VBUSVALID	BIT(22)
>>>>> +#define USBSS_IRQ_MISC_RAW_SESSVALID	BIT(20)
>>>>> +
>>>>> +/* IRQ_MISC_STATUS register bits */
>>>>> +#define USBSS_IRQ_MISC_VBUSVALID	BIT(22)
>>>>> +#define USBSS_IRQ_MISC_SESSVALID	BIT(20)
>>>>> +
>>>>> +/* IRQ_MISC_ENABLE_SET register bits */
>>>>> +#define USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID	BIT(22)
>>>>> +#define USBSS_IRQ_MISC_ENABLE_SET_SESSVALID	BIT(20)
>>>>> +
>>>>> +/* IRQ_MISC_ENABLE_CLR register bits */
>>>>> +#define USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID	BIT(22)
>>>>> +#define USBSS_IRQ_MISC_ENABLE_CLR_SESSVALID	BIT(20)
>>>>> +
>>>>> +/* IRQ_MISC_EOI register bits */
>>>>> +#define USBSS_IRQ_MISC_EOI_VECTOR	BIT(0)
>>>>> +
>>>>> +/* VBUS_STAT register bits */
>>>>> +#define USBSS_VBUS_STAT_SESSVALID	BIT(2)
>>>>> +#define USBSS_VBUS_STAT_VBUSVALID	BIT(0)
>>>>> +
>>>>> +/* Mask for PHY PLL REFCLK */
>>>>> +#define PHY_PLL_REFCLK_MASK	GENMASK(3, 0)
>>>>> +
>>>>> +#define DWC3_AM62_AUTOSUSPEND_DELAY	100
>>>>> +
>>>>> +struct dwc3_data {
>>>>> +	struct device *dev;
>>>>> +	void __iomem *usbss;
>>>>> +	struct clk *usb2_refclk;
>>>>> +	struct work_struct work;
>>>>> +	int vbus_irq;
>>>>> +	int rate_code;
>>>>> +	int connect;
>>>>> +	struct regmap *syscon;
>>>>> +	unsigned int offset;
>>>>> +	unsigned int vbus_divider;
>>>>> +};
>>>>> +
>>>>> +static const int dwc3_ti_rate_table[] = {	/* in KHZ */
>>>>> +	9600,
>>>>> +	10000,
>>>>> +	12000,
>>>>> +	19200,
>>>>> +	20000,
>>>>> +	24000,
>>>>> +	25000,
>>>>> +	26000,
>>>>> +	38400,
>>>>> +	40000,
>>>>> +	58000,
>>>>> +	50000,
>>>>> +	52000,
>>>>> +};
>>>>> +
>>>>> +static inline u32 dwc3_ti_readl(struct dwc3_data *data, u32 offset)
>>>>> +{
>>>>> +	return readl((data->usbss) + offset);
>>>>> +}
>>>>> +
>>>>> +static inline void dwc3_ti_writel(struct dwc3_data *data, u32 offset, u32 value)
>>>>> +{
>>>>> +	writel(value, (data->usbss) + offset);
>>>>> +}
>>>>> +
>>>>> +static void connect_detect_work(struct work_struct *work)
>>>>> +{
>>>>> +	struct dwc3_data *data =
>>>>> +		container_of(work, struct dwc3_data, work);
>>>>> +	u32 vbus_state, reg;
>>>>> +	int connect = 0;
>>>>> +
>>>>> +	/* Read the status for VBUS valid register */
>>>>> +	vbus_state = dwc3_ti_readl(data, USBSS_VBUS_STAT);
>>>>> +	vbus_state &= USBSS_VBUS_STAT_VBUSVALID;
>>>>> +
>>>>> +	if (vbus_state)
>>>>> +		connect = 1;
>>>>> +
>>>>> +	/* Set or clear mode valid bit based on connect or disconnect event */
>>>>> +	if (data->connect != connect) {
>>>>> +		reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
>>>>> +		if (connect)
>>>>> +			reg |= USBSS_MODE_VALID;
>>>>> +		else
>>>>> +			reg &= ~USBSS_MODE_VALID;
>>>>> +
>>>>> +		dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
>>>>> +		data->connect = connect;
>>>>> +	}
>>>>> +}
>>>>> +
>>>>> +static irqreturn_t connect_detect_irq_handler(int irq, void *dev_id)
>>>>> +{
>>>>> +	struct dwc3_data *data = dev_id;
>>>>> +	u32 reg;
>>>>> +
>>>>> +	/* Clear VBUS interrupt always to aviod queuing up redundant work items */
>>>>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_STATUS);
>>>>> +	reg |= USBSS_IRQ_MISC_VBUSVALID;
>>>>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_STATUS, reg);
>>>>> +
>>>>> +	queue_work(system_power_efficient_wq, &data->work);
>>>>> +
>>>>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_EOI);
>>>>> +	reg &= ~USBSS_IRQ_MISC_EOI_VECTOR;
>>>>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_EOI, reg);
>>>>> +	return IRQ_HANDLED;
>>>>> +}
>>>>> +
>>>>> +static int dwc3_ti_vbus_irq_setup(struct platform_device *pdev)
>>>>> +{
>>>>> +	struct device *dev = &pdev->dev;
>>>>> +	struct dwc3_data *data = platform_get_drvdata(pdev);
>>>>> +	int irq, ret;
>>>>> +
>>>>> +	/* Get the misc interrupt */
>>>>> +	irq = platform_get_irq(pdev, 0);
>>>>> +	if (irq < 0)
>>>>> +		return irq;
>>>>> +
>>>>> +	ret = devm_request_irq(dev, irq, connect_detect_irq_handler, IRQF_SHARED,
>>>>> +			       dev_name(dev), data);
>>>>> +	if (ret) {
>>>>> +		dev_err(dev, "failed to required IRQ #%d-->%d\n",
>>>>> +			irq, ret);
>>>>> +		return ret;
>>>>> +	}
>>>>> +
>>>>> +	data->vbus_irq = irq;
>>>>> +
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>> +static int phy_syscon_pll_refclk(struct dwc3_data *data)
>>>>> +{
>>>>> +	struct device *dev = data->dev;
>>>>> +	struct device_node *node = dev->of_node;
>>>>> +	struct of_phandle_args args;
>>>>> +	struct regmap *syscon;
>>>>> +	int ret;
>>>>> +
>>>>> +	syscon = syscon_regmap_lookup_by_phandle(node, "ti,syscon-phy-pll-refclk");
>>>>> +	if (IS_ERR(syscon)) {
>>>>> +		dev_err(dev, "unable to get ti,syscon-phy-pll-refclk regmap\n");
>>>>> +		return PTR_ERR(syscon);
>>>>> +	}
>>>>> +
>>>>> +	data->syscon = syscon;
>>>>> +
>>>>> +	ret = of_parse_phandle_with_fixed_args(node, "ti,syscon-phy-pll-refclk", 1,
>>>>> +					       0, &args);
>>>>> +	if (ret)
>>>>> +		return ret;
>>>>> +
>>>>> +	data->offset = args.args[0];
>>>>> +
>>>>> +	ret = regmap_update_bits(data->syscon, data->offset, PHY_PLL_REFCLK_MASK, data->rate_code);
>>>>> +	if (ret) {
>>>>> +		dev_err(dev, "failed to set phy pll reference clock rate\n");
>>>>> +		return ret;
>>>>> +	}
>>>>> +
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>> +static void dwc3_ti_enable_irqs(struct dwc3_data *data)
>>>>> +{
>>>>> +	u32 reg;
>>>>> +
>>>>> +	/* enable VBUSVALID interrupt */
>>>>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_ENABLE_SET);
>>>>> +	reg |= USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID;
>>>>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_ENABLE_SET, reg);
>>>>> +}
>>>>> +
>>>>> +static void dwc3_ti_disable_irqs(struct dwc3_data *data)
>>>>> +{
>>>>> +	u32 reg;
>>>>> +
>>>>> +	/* disable VBUSVALID interrupt */
>>>>> +	reg = dwc3_ti_readl(data, USBSS_IRQ_MISC_ENABLE_CLR);
>>>>> +	reg |= USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID;
>>>>> +	dwc3_ti_writel(data, USBSS_IRQ_MISC_ENABLE_CLR, reg);
>>>>> +}
>>>>> +
>>>>> +static int dwc3_ti_probe(struct platform_device *pdev)
>>>>> +{
>>>>> +	struct device *dev = &pdev->dev;
>>>>> +	struct device_node *node = pdev->dev.of_node;
>>>>> +	struct dwc3_data *data;
>>>>> +	int i, ret;
>>>>> +	unsigned long rate;
>>>>> +	u32 reg;
>>>>> +
>>>>> +	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
>>>>> +	if (!data)
>>>>> +		return -ENOMEM;
>>>>> +
>>>>> +	data->dev = dev;
>>>>> +	platform_set_drvdata(pdev, data);
>>>>> +
>>>>> +	data->usbss = devm_platform_ioremap_resource(pdev, 0);
>>>>> +	if (IS_ERR(data->usbss)) {
>>>>> +		dev_err(dev, "can't map IOMEM resource\n");
>>>>> +		return PTR_ERR(data->usbss);
>>>>> +	}
>>>>> +
>>>>> +	data->usb2_refclk = devm_clk_get(dev, "ref");
>>>>> +	if (IS_ERR(data->usb2_refclk)) {
>>>>> +		dev_err(dev, "can't get usb2_refclk\n");
>>>>> +		return PTR_ERR(data->usb2_refclk);
>>>>> +	}
>>>>> +
>>>>> +	/* Calculate the rate code */
>>>>> +	rate = clk_get_rate(data->usb2_refclk);
>>>>> +	rate /= 1000;	// To KHz
>>>>> +	for (i = 0; i < ARRAY_SIZE(dwc3_ti_rate_table); i++) {
>>>>> +		if (dwc3_ti_rate_table[i] == rate)
>>>>> +			break;
>>>>> +	}
>>>>> +
>>>>> +	if (i == ARRAY_SIZE(dwc3_ti_rate_table)) {
>>>>> +		dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate);
>>>>> +		ret = -EINVAL;
>>>>> +		goto err_clk_disable;
>>>>> +	}
>>>>> +
>>>>> +	data->rate_code = i;
>>>>> +
>>>>> +	/* Read the syscon property and set the rate code */
>>>>> +	ret = phy_syscon_pll_refclk(data);
>>>>> +	if (ret)
>>>>> +		goto err_clk_disable;
>>>>> +
>>>>> +	/* VBUS divider select */
>>>>> +	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
>>>>> +	reg = dwc3_ti_readl(data, USBSS_PHY_CONFIG);
>>>>> +	if (data->vbus_divider)
>>>>> +		reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT;
>>>>> +
>>>>> +	dwc3_ti_writel(data, USBSS_PHY_CONFIG, reg);
>>>>> +
>>>>> +	/* Initialize a work queue */
>>>>> +	ret = devm_work_autocancel(dev, &data->work, connect_detect_work);
>>>>> +	if (ret)
>>>>> +		goto err_clk_disable;
>>>>> +
>>>>> +	/* Read and set VBUS IRQ */
>>>>> +	ret = dwc3_ti_vbus_irq_setup(pdev);
>>>>> +	if (ret)
>>>>> +		goto err_clk_disable;
>>>>> +
>>>>> +	pm_runtime_set_active(dev);
>>>>> +	pm_runtime_enable(dev);
>>>>> +	/*
>>>>> +	 * Don't ignore its dependencies with its children
>>>>> +	 */
>>>>> +	pm_suspend_ignore_children(dev, false);
>>>>> +	clk_prepare_enable(data->usb2_refclk);
>>>>> +	pm_runtime_get_noresume(dev);
>>>>> +
>>>>> +	ret = of_platform_populate(node, NULL, NULL, dev);
>>>>> +	if (ret) {
>>>>> +		dev_err(dev, "failed to create dwc3 core: %d\n", ret);
>>>>> +		goto err_pm_disable;
>>>>> +	}
>>>>> +
>>>>> +	/* Enable vbus irq */
>>>>> +	dwc3_ti_enable_irqs(data);
>>>>> +
>>>>> +	connect_detect_work(&data->work);
>>>>> +
>>>>> +	/* Setting up autosuspend */
>>>>> +	pm_runtime_set_autosuspend_delay(dev, DWC3_AM62_AUTOSUSPEND_DELAY);
>>>>> +	pm_runtime_use_autosuspend(dev);
>>>>> +	pm_runtime_mark_last_busy(dev);
>>>>> +	pm_runtime_put_autosuspend(dev);
>>>>> +	return 0;
>>>>> +
>>>>> +err_pm_disable:
>>>>> +	clk_disable_unprepare(data->usb2_refclk);
>>>>> +	pm_runtime_disable(dev);
>>>>> +	pm_runtime_set_suspended(dev);
>>>>> +err_clk_disable:
>>>>> +	clk_put(data->usb2_refclk);
>>>>> +	return ret;
>>>>> +}
>>>>> +
>>>>> +static int dwc3_ti_remove_core(struct device *dev, void *c)
>>>>> +{
>>>>> +	struct platform_device *pdev = to_platform_device(dev);
>>>>> +
>>>>> +	platform_device_unregister(pdev);
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>> +static int dwc3_ti_remove(struct platform_device *pdev)
>>>>> +{
>>>>> +	struct device *dev = &pdev->dev;
>>>>> +	struct dwc3_data *data = platform_get_drvdata(pdev);
>>>>> +	u32 reg;
>>>>> +
>>>>> +	dwc3_ti_disable_irqs(data);
>>>>> +
>>>>> +	device_for_each_child(dev, NULL, dwc3_ti_remove_core);
>>>>> +
>>>>> +	/* Clear mode valid bit */
>>>>> +	reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
>>>>> +	reg &= ~USBSS_MODE_VALID;
>>>>> +	dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
>>>>> +
>>>>> +	pm_runtime_put_sync(dev);
>>>>> +	clk_disable_unprepare(data->usb2_refclk);
>>>>> +	pm_runtime_disable(dev);
>>>>> +	pm_runtime_set_suspended(dev);
>>>>> +
>>>>> +	clk_put(data->usb2_refclk);
>>>>> +	platform_set_drvdata(pdev, NULL);
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>> +#ifdef CONFIG_PM
>>>>> +static int dwc3_ti_suspend_common(struct device *dev)
>>>>> +{
>>>>> +	struct dwc3_data *data = dev_get_drvdata(dev);
>>>>> +
>>>>> +	/* disable irqs */
>>>>> +	dwc3_ti_disable_irqs(data);
>>>>> +
>>>>> +	clk_disable_unprepare(data->usb2_refclk);
>>>>> +
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>> +static int dwc3_ti_resume_common(struct device *dev)
>>>>> +{
>>>>> +	struct dwc3_data *data = dev_get_drvdata(dev);
>>>>> +
>>>>> +	clk_prepare_enable(data->usb2_refclk);
>>>>> +
>>>>> +	/* Enable irqs */
>>>>> +	dwc3_ti_enable_irqs(data);
>>>>> +
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>> +static UNIVERSAL_DEV_PM_OPS(dwc3_ti_pm_ops, dwc3_ti_suspend_common,
>>>>> +			    dwc3_ti_resume_common, NULL);
>>>>> +
>>>>> +#define DEV_PM_OPS	(&dwc3_ti_pm_ops)
>>>>> +#else
>>>>> +#define DEV_PM_OPS	NULL
>>>>> +#endif /* CONFIG_PM */
>>>>> +
>>>>> +static const struct of_device_id dwc3_ti_of_match[] = {
>>>>> +	{ .compatible = "ti,am62-usb"},
>>>>> +	{},
>>>>> +};
>>>>> +MODULE_DEVICE_TABLE(of, dwc3_ti_of_match);
>>>>> +
>>>>> +static struct platform_driver dwc3_ti_driver = {
>>>>> +	.probe		= dwc3_ti_probe,
>>>>> +	.remove		= dwc3_ti_remove,
>>>>> +	.driver		= {
>>>>> +		.name	= "dwc3-am62",
>>>>> +		.pm	= DEV_PM_OPS,
>>>>> +		.of_match_table = dwc3_ti_of_match,
>>>>> +	},
>>>>> +};
>>>>> +
>>>>> +module_platform_driver(dwc3_ti_driver);
>>>>> +
>>>>> +MODULE_ALIAS("platform:dwc3-am62");
>>>>> +MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
>>>>> +MODULE_LICENSE("GPL");
>>>>> +MODULE_DESCRIPTION("DesignWare USB3 TI Glue Layer")
>>
>>


-- 
Thanks,
Aswath