[PATCH v8 0/5] Add XHCI, EHCI and OHCI support for Broadcom STB SoS's

[PATCH v8 0/5] Add XHCI, EHCI and OHCI support for Broadcom STB SoS's

[Al Cooper]

v8 - The previous v7 had the wrong version of ehci-brcm.c. This time
     really, really add the changes Greg requested.

v7 - Cleanup ehci-brcm.c as requested by Greg Kroah-Hartman.
   - Split out Makefile re-order change into a separate commit.

v6 - Remove "contains:" from compatible section of
     brcm,bcm7445-ehci.yaml as requested by Rob Herring.

v5 - Use devm_platform_get_and_ioremap_resource() in ehci-brcm.c
     as requested by Andy Shevchenko.
   - Add pm_runtime_set_active() to ehci_resume() in ehci-brcm.c
     as requested by Alan Stern.

v4 - A few more fixes to the brcm,bcm7445-ehci.yaml dt-bindings
     document requested by Rob Herring.
   - Fixed ordering issue in MAINTAINERS as requested by
     Andy Shevchenko.

v3 - Addressed all of Andy Shevchenko's review comments for
     ehci-brcm.c.
   - Fixed the brcm,bcm7445-ehci.yaml dt-bindings document,
     dt_binding_check now passes.
   - Added the XHCI functionality to xhci-plat.c instead of creating
     new brcmstb files, as suggested by Mathias Nyman.

v2 - Addressed Andy Shevchenko's review comments.
   - Fixed dt_binding_check error pointed out by Rob Herring.
   - Removed pr_info message in ehci_brcm_init as suggested by
     Greg Kroah-Hartman.

This adds support for the XHCI, EHCI and OHCI host controllers found
in Broadcom STB SoC's. These drivers depend on getting access to the
new Broadcom STB USB PHY driver through a device-tree phandle and
will fail if the driver is not available.

Al Cooper (5):
  usb: xhci: Change the XHCI link order in the Makefile
  dt-bindings: Add Broadcom STB USB support
  usb: xhci: xhci-plat: Add support for Broadcom STB SoC's
  usb: ehci: Add new EHCI driver for Broadcom STB SoC's
  usb: host: Add ability to build new Broadcom STB USB drivers

 .../bindings/usb/brcm,bcm7445-ehci.yaml       |  59 ++++
 .../devicetree/bindings/usb/usb-xhci.txt      |   1 +
 MAINTAINERS                                   |   8 +
 drivers/usb/host/Kconfig                      |  20 ++
 drivers/usb/host/Makefile                     |  17 +-
 drivers/usb/host/ehci-brcm.c                  | 281 ++++++++++++++++++
 drivers/usb/host/xhci-plat.c                  |  10 +
 7 files changed, 390 insertions(+), 6 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/usb/brcm,bcm7445-ehci.yaml
 create mode 100644 drivers/usb/host/ehci-brcm.c

-- 
2.17.1

[PATCH v8 1/5] usb: xhci: Change the XHCI link order in the Makefile

[Al Cooper]

Some BRCMSTB USB chips have an XHCI, EHCI and OHCI controller
on the same port where XHCI handles 3.0 devices, EHCI handles 2.0
devices and OHCI handles <2.0 devices. Currently the Makefile
has XHCI linking at the bottom which will result in the XHIC driver
initalizing after the EHCI and OHCI drivers and any installed 3.0
device will be seen as a 2.0 device. Moving the XHCI linking
above the EHCI and OHCI linking fixes the issue.

Signed-off-by: Al Cooper <alcooperx@gmail.com>
---
 drivers/usb/host/Makefile | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/host/Makefile b/drivers/usb/host/Makefile
index b191361257cc..a7f0b8ff7179 100644
--- a/drivers/usb/host/Makefile
+++ b/drivers/usb/host/Makefile
@@ -37,6 +37,16 @@ endif
 
 obj-$(CONFIG_USB_PCI)	+= pci-quirks.o
 
+# NOTE: BRCMSTB systems require that xhci driver be linked before the
+# ehci/ohci drivers because they share a port and need the XHCI driver
+# to come up first to properly enumerate 3.0 devices.
+obj-$(CONFIG_USB_XHCI_HCD)	+= xhci-hcd.o
+obj-$(CONFIG_USB_XHCI_PCI)	+= xhci-pci.o
+obj-$(CONFIG_USB_XHCI_PLATFORM) += xhci-plat-hcd.o
+obj-$(CONFIG_USB_XHCI_HISTB)	+= xhci-histb.o
+obj-$(CONFIG_USB_XHCI_MTK)	+= xhci-mtk.o
+obj-$(CONFIG_USB_XHCI_TEGRA)	+= xhci-tegra.o
+
 obj-$(CONFIG_USB_EHCI_HCD)	+= ehci-hcd.o
 obj-$(CONFIG_USB_EHCI_PCI)	+= ehci-pci.o
 obj-$(CONFIG_USB_EHCI_HCD_PLATFORM)	+= ehci-platform.o
@@ -69,12 +79,6 @@ obj-$(CONFIG_USB_OHCI_HCD_DAVINCI)	+= ohci-da8xx.o
 
 obj-$(CONFIG_USB_UHCI_HCD)	+= uhci-hcd.o
 obj-$(CONFIG_USB_FHCI_HCD)	+= fhci.o
-obj-$(CONFIG_USB_XHCI_HCD)	+= xhci-hcd.o
-obj-$(CONFIG_USB_XHCI_PCI)	+= xhci-pci.o
-obj-$(CONFIG_USB_XHCI_PLATFORM) += xhci-plat-hcd.o
-obj-$(CONFIG_USB_XHCI_HISTB)	+= xhci-histb.o
-obj-$(CONFIG_USB_XHCI_MTK)	+= xhci-mtk.o
-obj-$(CONFIG_USB_XHCI_TEGRA)	+= xhci-tegra.o
 obj-$(CONFIG_USB_SL811_HCD)	+= sl811-hcd.o
 obj-$(CONFIG_USB_SL811_CS)	+= sl811_cs.o
 obj-$(CONFIG_USB_U132_HCD)	+= u132-hcd.o
-- 
2.17.1

Re: [PATCH v8 1/5] usb: xhci: Change the XHCI link order in the Makefile

[Florian Fainelli]

On 5/8/2020 2:19 PM, Al Cooper wrote:
> Some BRCMSTB USB chips have an XHCI, EHCI and OHCI controller
> on the same port where XHCI handles 3.0 devices, EHCI handles 2.0
> devices and OHCI handles <2.0 devices. Currently the Makefile
> has XHCI linking at the bottom which will result in the XHIC driver
> initalizing after the EHCI and OHCI drivers and any installed 3.0
> device will be seen as a 2.0 device. Moving the XHCI linking
> above the EHCI and OHCI linking fixes the issue.
> 
> Signed-off-by: Al Cooper <alcooperx@gmail.com>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

RE: [PATCH v8 1/5] usb: xhci: Change the XHCI link order in the Makefile

[Yoshihiro Shimoda]

Hi Al,

> From: Al Cooper, Sent: Saturday, May 9, 2020 6:19 AM
> 
> Some BRCMSTB USB chips have an XHCI, EHCI and OHCI controller
> on the same port where XHCI handles 3.0 devices, EHCI handles 2.0
> devices and OHCI handles <2.0 devices. Currently the Makefile
> has XHCI linking at the bottom which will result in the XHIC driver
> initalizing after the EHCI and OHCI drivers and any installed 3.0
> device will be seen as a 2.0 device. Moving the XHCI linking
> above the EHCI and OHCI linking fixes the issue.
> 
> Signed-off-by: Al Cooper <alcooperx@gmail.com>

I tested on my environment (r8a77951 and r8a77961) and then
I didn't detect any regression. So,

Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>

Best regards,
Yoshihiro Shimoda

[PATCH v8 2/5] dt-bindings: Add Broadcom STB USB support

[Al Cooper]

Add DT bindings for Broadcom STB USB EHCI and XHCI drivers.

NOTE: The OHCI driver is not included because it uses the generic
      platform driver.

Signed-off-by: Al Cooper <alcooperx@gmail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---
 .../bindings/usb/brcm,bcm7445-ehci.yaml       | 59 +++++++++++++++++++
 .../devicetree/bindings/usb/usb-xhci.txt      |  1 +
 2 files changed, 60 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/usb/brcm,bcm7445-ehci.yaml

diff --git a/Documentation/devicetree/bindings/usb/brcm,bcm7445-ehci.yaml b/Documentation/devicetree/bindings/usb/brcm,bcm7445-ehci.yaml
new file mode 100644
index 000000000000..2a9acf2b5a64
--- /dev/null
+++ b/Documentation/devicetree/bindings/usb/brcm,bcm7445-ehci.yaml
@@ -0,0 +1,59 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/usb/brcm,bcm7445-ehci.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Broadcom STB USB EHCI Controller Device Tree Bindings
+
+allOf:
+  - $ref: "usb-hcd.yaml"
+
+maintainers:
+  - Al Cooper <alcooperx@gmail.com>
+
+properties:
+  compatible:
+    const: brcm,bcm7445-ehci
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+    description: Clock specifier for the EHCI clock
+
+  clock-names:
+    const: sw_usb
+
+  phys:
+    maxItems: 1
+
+  phy-names:
+    const: usbphy
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - phys
+  - clocks
+
+additionalProperties: false
+
+examples:
+  - |
+    usb@f0b00300 {
+        compatible = "brcm,bcm7445-ehci";
+        reg = <0xf0b00300 0xa8>;
+        interrupts = <0x0 0x5a 0x0>;
+        phys = <&usbphy_0 0x0>;
+        phy-names = "usbphy";
+        clocks = <&usb20>;
+        clock-names = "sw_usb";
+    };
+
+...
diff --git a/Documentation/devicetree/bindings/usb/usb-xhci.txt b/Documentation/devicetree/bindings/usb/usb-xhci.txt
index dc025f126d71..23e89d798b1b 100644
--- a/Documentation/devicetree/bindings/usb/usb-xhci.txt
+++ b/Documentation/devicetree/bindings/usb/usb-xhci.txt
@@ -24,6 +24,7 @@ Required properties:
       device
     - "renesas,rcar-gen3-xhci" for a generic R-Car Gen3 or RZ/G2 compatible
       device
+    - "brcm,bcm7445-xhci" for Broadcom STB SoCs with XHCI
     - "xhci-platform" (deprecated)
 
     When compatible with the generic version, nodes must list the
-- 
2.17.1

Re: [PATCH v8 2/5] dt-bindings: Add Broadcom STB USB support

[Florian Fainelli]

On 5/8/2020 2:19 PM, Al Cooper wrote:
> Add DT bindings for Broadcom STB USB EHCI and XHCI drivers.
> 
> NOTE: The OHCI driver is not included because it uses the generic
>       platform driver.
> 
> Signed-off-by: Al Cooper <alcooperx@gmail.com>
> Reviewed-by: Rob Herring <robh@kernel.org>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

[PATCH v8 3/5] usb: xhci: xhci-plat: Add support for Broadcom STB SoC's

[Al Cooper]

Add support for Broadcom STB SoC's to the xhci platform driver

Signed-off-by: Al Cooper <alcooperx@gmail.com>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
---
 drivers/usb/host/xhci-plat.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 1d4f6f85f0fe..44406d0eb317 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -112,6 +112,10 @@ static const struct xhci_plat_priv xhci_plat_renesas_rcar_gen3 = {
 	SET_XHCI_PLAT_PRIV_FOR_RCAR(XHCI_RCAR_FIRMWARE_NAME_V3)
 };
 
+static const struct xhci_plat_priv xhci_plat_brcm = {
+	.quirks = XHCI_RESET_ON_RESUME,
+};
+
 static const struct of_device_id usb_xhci_of_match[] = {
 	{
 		.compatible = "generic-xhci",
@@ -147,6 +151,12 @@ static const struct of_device_id usb_xhci_of_match[] = {
 	}, {
 		.compatible = "renesas,rcar-gen3-xhci",
 		.data = &xhci_plat_renesas_rcar_gen3,
+	}, {
+		.compatible = "brcm,xhci-brcm-v2",
+		.data = &xhci_plat_brcm,
+	}, {
+		.compatible = "brcm,bcm7445-xhci",
+		.data = &xhci_plat_brcm,
 	},
 	{},
 };
-- 
2.17.1

Re: [PATCH v8 3/5] usb: xhci: xhci-plat: Add support for Broadcom STB SoC's

[Florian Fainelli]

On 5/8/2020 2:19 PM, Al Cooper wrote:
> Add support for Broadcom STB SoC's to the xhci platform driver
> 
> Signed-off-by: Al Cooper <alcooperx@gmail.com>
> Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

[PATCH v8 4/5] usb: ehci: Add new EHCI driver for Broadcom STB SoC's

[Al Cooper]

Add a new EHCI driver for Broadcom STB SoC's. A new EHCI driver
was created instead of adding support to the existing ehci platform
driver because of the code required to workaround bugs in the EHCI
controller. The primary workround is for a bug where the Core
violates the SOF interval between the first two SOFs transmitted after
resume. This only happens if the resume occurs near the end of a
microframe. The fix is to intercept the echi-hcd request to complete
RESUME and align it to the start of the next microframe.

Signed-off-by: Al Cooper <alcooperx@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
---
 drivers/usb/host/ehci-brcm.c | 281 +++++++++++++++++++++++++++++++++++
 1 file changed, 281 insertions(+)
 create mode 100644 drivers/usb/host/ehci-brcm.c

diff --git a/drivers/usb/host/ehci-brcm.c b/drivers/usb/host/ehci-brcm.c
new file mode 100644
index 000000000000..763f0b9b3f37
--- /dev/null
+++ b/drivers/usb/host/ehci-brcm.c
@@ -0,0 +1,281 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2020, Broadcom */
+
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/usb.h>
+#include <linux/usb/hcd.h>
+#include <linux/iopoll.h>
+
+#include "ehci.h"
+
+#define hcd_to_ehci_priv(h) ((struct brcm_priv *)hcd_to_ehci(h)->priv)
+
+struct brcm_priv {
+	struct clk *clk;
+};
+
+/*
+ * ehci_brcm_wait_for_sof
+ * Wait for start of next microframe, then wait extra delay microseconds
+ */
+static inline void ehci_brcm_wait_for_sof(struct ehci_hcd *ehci, u32 delay)
+{
+	u32 frame_idx = ehci_readl(ehci, &ehci->regs->frame_index);
+	u32 val;
+	int res;
+
+	/* Wait for next microframe (every 125 usecs) */
+	res = readl_relaxed_poll_timeout(&ehci->regs->frame_index, val,
+					 val != frame_idx, 1, 130);
+	if (res)
+		dev_err(ehci_to_hcd(ehci)->self.controller,
+			"Error waiting for SOF\n");
+	udelay(delay);
+}
+
+/*
+ * ehci_brcm_hub_control
+ * The EHCI controller has a bug where it can violate the SOF
+ * interval between the first two SOF's transmitted after resume
+ * if the resume occurs near the end of the microframe. This causees
+ * the controller to detect babble on the suspended port and
+ * will eventually cause the controller to reset the port.
+ * The fix is to Intercept the echi-hcd request to complete RESUME and
+ * align it to the start of the next microframe.
+ * See SWLINUX-1909 for more details
+ */
+static int ehci_brcm_hub_control(
+	struct usb_hcd	*hcd,
+	u16		typeReq,
+	u16		wValue,
+	u16		wIndex,
+	char		*buf,
+	u16		wLength)
+{
+	struct ehci_hcd	*ehci = hcd_to_ehci(hcd);
+	int		ports = HCS_N_PORTS(ehci->hcs_params);
+	u32 __iomem	*status_reg;
+	unsigned long flags;
+	int retval, irq_disabled = 0;
+
+	status_reg = &ehci->regs->port_status[(wIndex & 0xff) - 1];
+
+	/*
+	 * RESUME is cleared when GetPortStatus() is called 20ms after start
+	 * of RESUME
+	 */
+	if ((typeReq == GetPortStatus) &&
+	    (wIndex && wIndex <= ports) &&
+	    ehci->reset_done[wIndex-1] &&
+	    time_after_eq(jiffies, ehci->reset_done[wIndex-1]) &&
+	    (ehci_readl(ehci, status_reg) & PORT_RESUME)) {
+
+		/*
+		 * to make sure we are not interrupted until RESUME bit
+		 * is cleared, disable interrupts on current CPU
+		 */
+		ehci_dbg(ehci, "SOF alignment workaround\n");
+		irq_disabled = 1;
+		local_irq_save(flags);
+		ehci_brcm_wait_for_sof(ehci, 5);
+	}
+	retval = ehci_hub_control(hcd, typeReq, wValue, wIndex, buf, wLength);
+	if (irq_disabled)
+		local_irq_restore(flags);
+	return retval;
+}
+
+static int ehci_brcm_reset(struct usb_hcd *hcd)
+{
+	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
+	int len;
+
+	ehci->big_endian_mmio = 1;
+
+	ehci->caps = (void __iomem *)hcd->regs;
+	len = HC_LENGTH(ehci, ehci_readl(ehci, &ehci->caps->hc_capbase));
+	ehci->regs = (void __iomem *)(hcd->regs + len);
+
+	/* This fixes the lockup during reboot due to prior interrupts */
+	ehci_writel(ehci, CMD_RESET, &ehci->regs->command);
+	mdelay(10);
+
+	/*
+	 * SWLINUX-1705: Avoid OUT packet underflows during high memory
+	 *   bus usage
+	 * port_status[0x0f] = Broadcom-proprietary USB_EHCI_INSNREG00 @ 0x90
+	 */
+	ehci_writel(ehci, 0x00800040, &ehci->regs->port_status[0x10]);
+	ehci_writel(ehci, 0x00000001, &ehci->regs->port_status[0x12]);
+
+	return ehci_setup(hcd);
+}
+
+static struct hc_driver __read_mostly ehci_brcm_hc_driver;
+
+static const struct ehci_driver_overrides brcm_overrides __initconst = {
+	.reset = ehci_brcm_reset,
+	.extra_priv_size = sizeof(struct brcm_priv),
+};
+
+static int ehci_brcm_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct resource *res_mem;
+	struct brcm_priv *priv;
+	struct usb_hcd *hcd;
+	int irq;
+	int err;
+
+	err = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
+	if (err)
+		return err;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq <= 0)
+		return irq;
+
+	/* Hook the hub control routine to work around a bug */
+	ehci_brcm_hc_driver.hub_control = ehci_brcm_hub_control;
+
+	/* initialize hcd */
+	hcd = usb_create_hcd(&ehci_brcm_hc_driver, dev, dev_name(dev));
+	if (!hcd)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, hcd);
+	priv = hcd_to_ehci_priv(hcd);
+
+	priv->clk = devm_clk_get_optional(dev, NULL);
+	if (IS_ERR(priv->clk)) {
+		err = PTR_ERR(priv->clk);
+		goto err_hcd;
+	}
+
+	err = clk_prepare_enable(priv->clk);
+	if (err)
+		goto err_hcd;
+
+	hcd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res_mem);
+	if (IS_ERR(hcd->regs)) {
+		err = PTR_ERR(hcd->regs);
+		goto err_clk;
+	}
+	hcd->rsrc_start = res_mem->start;
+	hcd->rsrc_len = resource_size(res_mem);
+	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
+	if (err)
+		goto err_clk;
+
+	device_wakeup_enable(hcd->self.controller);
+	device_enable_async_suspend(hcd->self.controller);
+
+	return 0;
+
+err_clk:
+	clk_disable_unprepare(priv->clk);
+err_hcd:
+	usb_put_hcd(hcd);
+
+	return err;
+}
+
+static int ehci_brcm_remove(struct platform_device *dev)
+{
+	struct usb_hcd *hcd = platform_get_drvdata(dev);
+	struct brcm_priv *priv = hcd_to_ehci_priv(hcd);
+
+	usb_remove_hcd(hcd);
+	clk_disable_unprepare(priv->clk);
+	usb_put_hcd(hcd);
+	return 0;
+}
+
+static int __maybe_unused ehci_brcm_suspend(struct device *dev)
+{
+	int ret;
+	struct usb_hcd *hcd = dev_get_drvdata(dev);
+	struct brcm_priv *priv = hcd_to_ehci_priv(hcd);
+	bool do_wakeup = device_may_wakeup(dev);
+
+	ret = ehci_suspend(hcd, do_wakeup);
+	if (ret)
+		return ret;
+	clk_disable_unprepare(priv->clk);
+	return 0;
+}
+
+static int __maybe_unused ehci_brcm_resume(struct device *dev)
+{
+	struct usb_hcd *hcd = dev_get_drvdata(dev);
+	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
+	struct brcm_priv *priv = hcd_to_ehci_priv(hcd);
+	int err;
+
+	err = clk_prepare_enable(priv->clk);
+	if (err)
+		return err;
+	/*
+	 * SWLINUX-1705: Avoid OUT packet underflows during high memory
+	 *   bus usage
+	 * port_status[0x0f] = Broadcom-proprietary USB_EHCI_INSNREG00
+	 * @ 0x90
+	 */
+	ehci_writel(ehci, 0x00800040, &ehci->regs->port_status[0x10]);
+	ehci_writel(ehci, 0x00000001, &ehci->regs->port_status[0x12]);
+
+	ehci_resume(hcd, false);
+
+	pm_runtime_disable(dev);
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(ehci_brcm_pm_ops, ehci_brcm_suspend,
+		ehci_brcm_resume);
+
+static const struct of_device_id brcm_ehci_of_match[] = {
+	{ .compatible = "brcm,ehci-brcm-v2", },
+	{ .compatible = "brcm,bcm7445-ehci", },
+	{}
+};
+
+static struct platform_driver ehci_brcm_driver = {
+	.probe		= ehci_brcm_probe,
+	.remove		= ehci_brcm_remove,
+	.shutdown	= usb_hcd_platform_shutdown,
+	.driver		= {
+		.name	= "ehci-brcm",
+		.pm	= &ehci_brcm_pm_ops,
+		.of_match_table = brcm_ehci_of_match,
+	}
+};
+
+static int __init ehci_brcm_init(void)
+{
+	if (usb_disabled())
+		return -ENODEV;
+
+	ehci_init_driver(&ehci_brcm_hc_driver, &brcm_overrides);
+	return platform_driver_register(&ehci_brcm_driver);
+}
+module_init(ehci_brcm_init);
+
+static void __exit ehci_brcm_exit(void)
+{
+	platform_driver_unregister(&ehci_brcm_driver);
+}
+module_exit(ehci_brcm_exit);
+
+MODULE_ALIAS("platform:ehci-brcm");
+MODULE_DESCRIPTION("EHCI Broadcom STB driver");
+MODULE_AUTHOR("Al Cooper");
+MODULE_LICENSE("GPL");
-- 
2.17.1

Re: [PATCH v8 4/5] usb: ehci: Add new EHCI driver for Broadcom STB SoC's

[Florian Fainelli]

On 5/8/2020 2:19 PM, Al Cooper wrote:
> Add a new EHCI driver for Broadcom STB SoC's. A new EHCI driver
> was created instead of adding support to the existing ehci platform
> driver because of the code required to workaround bugs in the EHCI
> controller. The primary workround is for a bug where the Core
> violates the SOF interval between the first two SOFs transmitted after
> resume. This only happens if the resume occurs near the end of a
> microframe. The fix is to intercept the echi-hcd request to complete
> RESUME and align it to the start of the next microframe.
> 
> Signed-off-by: Al Cooper <alcooperx@gmail.com>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

Re: [PATCH v8 4/5] usb: ehci: Add new EHCI driver for Broadcom STB SoC's

[Alan Stern]

On Fri, 8 May 2020, Al Cooper wrote:

A few minor typos in the patch description:

> Add a new EHCI driver for Broadcom STB SoC's. A new EHCI driver
> was created instead of adding support to the existing ehci platform
> driver because of the code required to workaround bugs in the EHCI
-----------------------------------------^

"workaround" is a noun; the verb form is "work around".

> controller. The primary workround is for a bug where the Core
-----------------------------^

Missing "a".

> violates the SOF interval between the first two SOFs transmitted after
> resume. This only happens if the resume occurs near the end of a
> microframe. The fix is to intercept the echi-hcd request to complete
-------------------------------------------^

ehci, not echi.

> RESUME and align it to the start of the next microframe.
> 
> Signed-off-by: Al Cooper <alcooperx@gmail.com>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> ---

Basically this new driver is fine.  However...

> +static inline void ehci_brcm_wait_for_sof(struct ehci_hcd *ehci, u32 delay)
> +{
> +	u32 frame_idx = ehci_readl(ehci, &ehci->regs->frame_index);
> +	u32 val;
> +	int res;
> +
> +	/* Wait for next microframe (every 125 usecs) */
> +	res = readl_relaxed_poll_timeout(&ehci->regs->frame_index, val,
> +					 val != frame_idx, 1, 130);
> +	if (res)
> +		dev_err(ehci_to_hcd(ehci)->self.controller,
> +			"Error waiting for SOF\n");

If this patch is going to be redone anyway, you might as well change
dev_err() to ehci_err() -- that's what it's for.  I should have noticed
this earlier, sorry.

> +static int ehci_brcm_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct resource *res_mem;
> +	struct brcm_priv *priv;
> +	struct usb_hcd *hcd;
> +	int irq;
> +	int err;
> +
> +	err = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
> +	if (err)
> +		return err;
> +
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq <= 0)
> +		return irq;

I don't want to get involved in the question of whether or not 0 is a 
valid IRQ number.  The consensus has gone back and forth over the 
years, and it just doesn't seem important.

However, as Sergei points out, if 0 is going to be regarded as an 
invalid value then we shouldn't return 0 from the probe function here.

I'll leave the decision on how to handle this matter up to Greg.  :-)

Alan Stern

Re: [PATCH v8 4/5] usb: ehci: Add new EHCI driver for Broadcom STB SoC's

[Andy Shevchenko]

On Sat, May 9, 2020 at 3:47 AM Alan Stern <stern@rowland.harvard.edu> wrote:
> On Fri, 8 May 2020, Al Cooper wrote:

...

> > +     irq = platform_get_irq(pdev, 0);
> > +     if (irq <= 0)
> > +             return irq;
>
> I don't want to get involved in the question of whether or not 0 is a
> valid IRQ number.  The consensus has gone back and forth over the
> years, and it just doesn't seem important.
>
> However, as Sergei points out, if 0 is going to be regarded as an
> invalid value then we shouldn't return 0 from the probe function here.

The most of the drivers rely on the fact that on platforms where it's
the case (yes, we have you-know-which architecture has some legacy
stuff there) request_irq() will fail anyway.

> I'll leave the decision on how to handle this matter up to Greg.  :-)

Me too.

-- 
With Best Regards,
Andy Shevchenko

[PATCH v8 5/5] usb: host: Add ability to build new Broadcom STB USB drivers

[Al Cooper]

Add the build system changes needed to get the Broadcom STB XHCI,
EHCI and OHCI functionality working. The OHCI support does not
require anything unique to Broadcom so the standard ohci-platform
driver is being used. Also update MAINTAINERS.

Signed-off-by: Al Cooper <alcooperx@gmail.com>
---
 MAINTAINERS               |  8 ++++++++
 drivers/usb/host/Kconfig  | 20 ++++++++++++++++++++
 drivers/usb/host/Makefile |  1 +
 3 files changed, 29 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 2926327e4976..fb55300c2a84 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3481,6 +3481,14 @@ S:	Supported
 F:	Documentation/devicetree/bindings/i2c/brcm,brcmstb-i2c.yaml
 F:	drivers/i2c/busses/i2c-brcmstb.c
 
+BROADCOM BRCMSTB USB EHCI DRIVER
+M:	Al Cooper <alcooperx@gmail.com>
+L:	linux-usb@vger.kernel.org
+L:	bcm-kernel-feedback-list@broadcom.com
+S:	Maintained
+F:	Documentation/devicetree/bindings/usb/brcm,bcm7445-ehci.yaml
+F:	drivers/usb/host/ehci-brcm.*
+
 BROADCOM BRCMSTB USB2 and USB3 PHY DRIVER
 M:	Al Cooper <alcooperx@gmail.com>
 L:	linux-kernel@vger.kernel.org
diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
index 55bdfdf11e4c..973386bbb522 100644
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -97,6 +97,26 @@ config USB_XHCI_TEGRA
 
 endif # USB_XHCI_HCD
 
+config USB_EHCI_BRCMSTB
+       tristate
+
+config USB_BRCMSTB
+	tristate "Broadcom STB USB support"
+	depends on (ARCH_BRCMSTB && PHY_BRCM_USB) || COMPILE_TEST
+	select USB_OHCI_HCD_PLATFORM if USB_OHCI_HCD
+	select USB_EHCI_BRCMSTB if USB_EHCI_HCD
+	select USB_XHCI_PLATFORM if USB_XHCI_HCD
+	help
+	  Enables support for XHCI, EHCI and OHCI host controllers
+	  found in Broadcom STB SoC's.
+
+	  To compile these drivers as modules, choose M here: the
+	  modules will be called ohci-platform.ko, ehci-brcm.ko and
+	  xhci-plat-hcd.ko
+
+	  Disabling this will keep the controllers and corresponding
+	  PHYs powered down.
+
 config USB_EHCI_HCD
 	tristate "EHCI HCD (USB 2.0) support"
 	depends on HAS_DMA && HAS_IOMEM
diff --git a/drivers/usb/host/Makefile b/drivers/usb/host/Makefile
index a7f0b8ff7179..265e26cf9209 100644
--- a/drivers/usb/host/Makefile
+++ b/drivers/usb/host/Makefile
@@ -59,6 +59,7 @@ obj-$(CONFIG_USB_EHCI_HCD_STI)	+= ehci-st.o
 obj-$(CONFIG_USB_EHCI_EXYNOS)	+= ehci-exynos.o
 obj-$(CONFIG_USB_EHCI_HCD_AT91) += ehci-atmel.o
 obj-$(CONFIG_USB_EHCI_TEGRA)	+= ehci-tegra.o
+obj-$(CONFIG_USB_EHCI_BRCMSTB)	+= ehci-brcm.o
 
 obj-$(CONFIG_USB_OXU210HP_HCD)	+= oxu210hp-hcd.o
 obj-$(CONFIG_USB_ISP116X_HCD)	+= isp116x-hcd.o
-- 
2.17.1

Re: [PATCH v8 5/5] usb: host: Add ability to build new Broadcom STB USB drivers

[Florian Fainelli]

On 5/8/2020 2:19 PM, Al Cooper wrote:
> Add the build system changes needed to get the Broadcom STB XHCI,
> EHCI and OHCI functionality working. The OHCI support does not
> require anything unique to Broadcom so the standard ohci-platform
> driver is being used. Also update MAINTAINERS.
> 
> Signed-off-by: Al Cooper <alcooperx@gmail.com>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian