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usb: misc: Add support for Microchip USB5744

PATCH In review Michal Simek 3 participants 9 messages Feb 9, 2021 – Mar 4, 2021

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Michal Simek

author
#0 lore raw

v2 cover usb: misc: Add support for Microchip USB5744

Hi,

the series is adding basic support for this USB hub. The key part is running reset over GPIO line and when i2c is connected it is necessary to send command to boot the hub. This chip is available on Xilinx zcu100/Ultra96 v1 board.

Thanks,
Michal

Changes in v2:
- s/USB_USB5744/USB_HUB_USB5744/g
- Fix order in Makefile and Kconfig

Piyush Mehta (2):
dt-bindings: usb: misc: Add binding for Microchip usb5744 hub
usb: misc: usb5744: Add support for USB hub controller

 .../bindings/usb/microchip,usb5744.yaml       |  56 +++++++++
 MAINTAINERS                                   |   2 +
 drivers/usb/misc/Kconfig                      |   9 ++
 drivers/usb/misc/Makefile                     |   1 +
 drivers/usb/misc/usb5744.c                    | 115 ++++++++++++++++++
 5 files changed, 183 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/usb/microchip,usb5744.yaml
 create mode 100644 drivers/usb/misc/usb5744.c
Signature · 7 lines
2.30.0


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author
#1 lore raw

PATCH v2 1/2 dt-bindings: usb: misc: Add binding for Microchip usb5744 hub

From: Piyush Mehta <[email protected]>

Added dt binding for usb5744 driver.

Signed-off-by Piyush Mehta <[email protected]>
Signed-off-by Michal Simek <[email protected]>

---

Changes in v2: None

 .../bindings/usb/microchip,usb5744.yaml       | 56 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 57 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/usb/microchip,usb5744.yaml
Documentation/devicetree/bindings/usb/microchip,usb5744.yaml new file +56 -0
new file mode 100644
index 000000000000..fe222f6db81d
@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/usb/microchip,usb5744.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Bindings for the Microchip USB5744 4-port Hub Controller
+
+description:
+  Microchip’s USB5744 SmartHub™ IC is a 4 port, SuperSpeed (SS)/Hi-Speed (HS),
+  low power, low pin count configurable and fully compliant with the USB 3.1
+  Gen 1 specification. The USB5744 also supports Full Speed (FS) and Low Speed
+  (LS) USB signaling, offering complete coverage of all defined USB operating
+  speeds. The new SuperSpeed hubs operate in parallel with the USB 2.0
+  controller, so 5 Gbps SuperSpeed data transfers are not affected by slower
+  USB 2.0 traffic.
+
+maintainers:
+  - Piyush Mehta <[email protected]>
+  - Michal Simek <[email protected]>
+
+properties:
+  compatible:
+    const: microchip,usb5744
+
+  reg:
+    maxItems: 1
+    description: |
+      Specifies the i2c slave address, it is required and should be 0x2d
+      if I2C is used.
+
+  reset-gpios:
+    maxItems: 1
+    description:
+      The phandle and specifier for the GPIO that controls the RESET line of
+      USB hub.
+
+required:
+  - compatible
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        usb5744@2d {
+            compatible = "microchip,usb5744";
+            reg = <0x2d>;
+            reset-gpios = <&gpio 44 GPIO_ACTIVE_HIGH>;
+        };
+    };
MAINTAINERS +1 -0
index 41e8d3d7faec..7439471b5d37 100644
@@ -2697,6 +2697,7 @@ W:	http://wiki.xilinx.com
 T:	git https://github.com/Xilinx/linux-xlnx.git
 F:	Documentation/devicetree/bindings/i2c/cdns,i2c-r1p10.yaml
 F:	Documentation/devicetree/bindings/i2c/xlnx,xps-iic-2.00.a.yaml
+F:	Documentation/devicetree/bindings/usb/microchip,usb5744.yaml
 F:	arch/arm/mach-zynq/
 F:	drivers/block/xsysace.c
 F:	drivers/clocksource/timer-cadence-ttc.c
Signature · 7 lines
2.30.0


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maintainer
#2 lore raw

Re: [PATCH v2 1/2] dt-bindings: usb: misc: Add binding for Microchip usb5744 hub

Quoted 41 lines · Michal Simek

From: Piyush Mehta <[email protected]>

Added dt binding for usb5744 driver.

Signed-off-by Piyush Mehta <[email protected]>
Signed-off-by Michal Simek <[email protected]>

---

Changes in v2: None

 .../bindings/usb/microchip,usb5744.yaml       | 56 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 57 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/usb/microchip,usb5744.yaml
Documentation/devicetree/bindings/usb/microchip,usb5744.yaml new file +20 -0
new file mode 100644
index 000000000000..fe222f6db81d
@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/usb/microchip,usb5744.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Bindings for the Microchip USB5744 4-port Hub Controller
+
+description:
+  Microchip’s USB5744 SmartHub™ IC is a 4 port, SuperSpeed (SS)/Hi-Speed (HS),
+  low power, low pin count configurable and fully compliant with the USB 3.1
+  Gen 1 specification. The USB5744 also supports Full Speed (FS) and Low Speed
+  (LS) USB signaling, offering complete coverage of all defined USB operating
+  speeds. The new SuperSpeed hubs operate in parallel with the USB 2.0
+  controller, so 5 Gbps SuperSpeed data transfers are not affected by slower
+  USB 2.0 traffic.
+
+maintainers:
+  - Piyush Mehta <[email protected]>
+  - Michal Simek <[email protected]>

Documentation/devicetree/bindings/usb/microchip,usb5744.yaml line 30

Quoted 10 lines
Documentation/devicetree/bindings/usb/microchip,usb5744.yaml new file +10 -0
+
+properties:
+  compatible:
+    const: microchip,usb5744
+
+  reg:
+    maxItems: 1
+    description: |
+      Specifies the i2c slave address, it is required and should be 0x2d
+      if I2C is used.

If I2C is not used, then this should be underneath the USB host as a USB device. That also implies a different compatible string. I'd suggest you just say I2C is required if that's your use.

'const: 0x2d' instead of maxItems is the schema to express the address if fixed.

Quoted 41 lines
Documentation/devicetree/bindings/usb/microchip,usb5744.yaml new file +26 -0
+
+  reset-gpios:
+    maxItems: 1
+    description:
+      The phandle and specifier for the GPIO that controls the RESET line of
+      USB hub.
+
+required:
+  - compatible
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        usb5744@2d {
+            compatible = "microchip,usb5744";
+            reg = <0x2d>;
+            reset-gpios = <&gpio 44 GPIO_ACTIVE_HIGH>;
+        };
+    };
MAINTAINERS +1 -0
index 41e8d3d7faec..7439471b5d37 100644
@@ -2697,6 +2697,7 @@ W:	http://wiki.xilinx.com
 T:	git https://github.com/Xilinx/linux-xlnx.git
 F:	Documentation/devicetree/bindings/i2c/cdns,i2c-r1p10.yaml
 F:	Documentation/devicetree/bindings/i2c/xlnx,xps-iic-2.00.a.yaml
+F:	Documentation/devicetree/bindings/usb/microchip,usb5744.yaml
 F:	arch/arm/mach-zynq/
 F:	drivers/block/xsysace.c
 F:	drivers/clocksource/timer-cadence-ttc.c
Signature · 1 line
2.30.0
author
#3 lore raw

Re: [PATCH v2 1/2] dt-bindings: usb: misc: Add binding for Microchip usb5744 hub

Hi Rob,

Quoted 48 lines · Rob Herring
Quoted 47 lines · Michal Simek

From: Piyush Mehta <[email protected]>

Added dt binding for usb5744 driver.

Signed-off-by Piyush Mehta <[email protected]>
Signed-off-by Michal Simek <[email protected]>

---

Changes in v2: None

 .../bindings/usb/microchip,usb5744.yaml       | 56 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 57 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/usb/microchip,usb5744.yaml
Documentation/devicetree/bindings/usb/microchip,usb5744.yaml new file +26 -0
new file mode 100644
index 000000000000..fe222f6db81d
@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/usb/microchip,usb5744.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Bindings for the Microchip USB5744 4-port Hub Controller
+
+description:
+  Microchip’s USB5744 SmartHub™ IC is a 4 port, SuperSpeed (SS)/Hi-Speed (HS),
+  low power, low pin count configurable and fully compliant with the USB 3.1
+  Gen 1 specification. The USB5744 also supports Full Speed (FS) and Low Speed
+  (LS) USB signaling, offering complete coverage of all defined USB operating
+  speeds. The new SuperSpeed hubs operate in parallel with the USB 2.0
+  controller, so 5 Gbps SuperSpeed data transfers are not affected by slower
+  USB 2.0 traffic.
+
+maintainers:
+  - Piyush Mehta <[email protected]>
+  - Michal Simek <[email protected]>
+
+properties:
+  compatible:
+    const: microchip,usb5744
+
+  reg:
Quoted 8 lines

Documentation/devicetree/bindings/usb/microchip,usb5744.yaml line 30

Quoted 4 lines
Documentation/devicetree/bindings/usb/microchip,usb5744.yaml new file +4 -0
+    maxItems: 1
+    description: |
+      Specifies the i2c slave address, it is required and should be 0x2d
+      if I2C is used.

If I2C is not used, then this should be underneath the USB host as a USB device. That also implies a different compatible string. I'd suggest you just say I2C is required if that's your use.

We can't say that i2c is required because we have both cases. One is really usb hub connected over i2c which at least requires to send one smbus command to start operate. But it can be extended to add more features - limit speeds, disable ports, etc.

And the second is really the same usb hub without i2c connected which runs in default mode. But reset is required to ensure proper reset sequence.
Hub also have external clock chip which is not handled now because it is just crystal on the board but if you want I can also model it via fixed clock and call clock enable for it.

It is the same use case as is with
Documentation/devicetree/bindings/usb/usb3503.txt

Can you please elaborate why different compatible string should be used? It is still the same device and not quite sure why different compatible string should be used.

Do you also want to example where this node is the part of usb node?

Quoted 3 lines

'const: 0x2d' instead of maxItems is the schema to express the address if fixed.

Will fix.

Thanks,
Michal

_______________________________________________
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maintainer
#4 lore raw

Re: [PATCH v2 1/2] dt-bindings: usb: misc: Add binding for Microchip usb5744 hub

Quoted 73 lines · Michal Simek

Hi Rob,

Quoted 48 lines · Rob Herring
Quoted 47 lines · Michal Simek

From: Piyush Mehta <[email protected]>

Added dt binding for usb5744 driver.

Signed-off-by Piyush Mehta <[email protected]>
Signed-off-by Michal Simek <[email protected]>

---

Changes in v2: None

 .../bindings/usb/microchip,usb5744.yaml       | 56 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 57 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/usb/microchip,usb5744.yaml
Documentation/devicetree/bindings/usb/microchip,usb5744.yaml new file +26 -0
new file mode 100644
index 000000000000..fe222f6db81d
@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/usb/microchip,usb5744.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Bindings for the Microchip USB5744 4-port Hub Controller
+
+description:
+  Microchip’s USB5744 SmartHub™ IC is a 4 port, SuperSpeed (SS)/Hi-Speed (HS),
+  low power, low pin count configurable and fully compliant with the USB 3.1
+  Gen 1 specification. The USB5744 also supports Full Speed (FS) and Low Speed
+  (LS) USB signaling, offering complete coverage of all defined USB operating
+  speeds. The new SuperSpeed hubs operate in parallel with the USB 2.0
+  controller, so 5 Gbps SuperSpeed data transfers are not affected by slower
+  USB 2.0 traffic.
+
+maintainers:
+  - Piyush Mehta <[email protected]>
+  - Michal Simek <[email protected]>
+
+properties:
+  compatible:
+    const: microchip,usb5744
+
+  reg:
Quoted 8 lines

Documentation/devicetree/bindings/usb/microchip,usb5744.yaml line 30

Quoted 4 lines
Documentation/devicetree/bindings/usb/microchip,usb5744.yaml new file +4 -0
+    maxItems: 1
+    description: |
+      Specifies the i2c slave address, it is required and should be 0x2d
+      if I2C is used.

If I2C is not used, then this should be underneath the USB host as a USB device. That also implies a different compatible string. I'd suggest you just say I2C is required if that's your use.

We can't say that i2c is required because we have both cases. One is really usb hub connected over i2c which at least requires to send one smbus command to start operate. But it can be extended to add more features - limit speeds, disable ports, etc.

And the second is really the same usb hub without i2c connected which runs in default mode. But reset is required to ensure proper reset sequence.
Hub also have external clock chip which is not handled now because it is just crystal on the board but if you want I can also model it via fixed clock and call clock enable for it.

Quoted 2 lines

It is the same use case as is with
Documentation/devicetree/bindings/usb/usb3503.txt

Yes, there are examples of how we don't want to do it.

Quoted 5 lines

Can you please elaborate why different compatible string should be used? It is still the same device and not quite sure why different compatible string should be used.

Do you also want to example where this node is the part of usb node?

See usb/usb-device.txt. And there is this[1] under review.

For these cases with I2C, I'd really rather see the hub always under the USB bus with a link to the I2C bus when connected.

Rob

[1] https://lore.kernel.org/linux-devicetree/20210210091015.v5.1.I248292623d3d0f6a4f0c5bc58478ca3c0062b49a@changeid/

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author
#5 lore raw

Re: [PATCH v2 1/2] dt-bindings: usb: misc: Add binding for Microchip usb5744 hub

Hi Rob,

Quoted 74 lines · Rob Herring
Quoted 73 lines · Michal Simek

Hi Rob,

Quoted 48 lines · Rob Herring
Quoted 47 lines · Michal Simek

From: Piyush Mehta <[email protected]>

Added dt binding for usb5744 driver.

Signed-off-by Piyush Mehta <[email protected]>
Signed-off-by Michal Simek <[email protected]>

---

Changes in v2: None

 .../bindings/usb/microchip,usb5744.yaml       | 56 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 57 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/usb/microchip,usb5744.yaml
Documentation/devicetree/bindings/usb/microchip,usb5744.yaml new file +26 -0
new file mode 100644
index 000000000000..fe222f6db81d
@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/usb/microchip,usb5744.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Bindings for the Microchip USB5744 4-port Hub Controller
+
+description:
+  Microchip’s USB5744 SmartHub™ IC is a 4 port, SuperSpeed (SS)/Hi-Speed (HS),
+  low power, low pin count configurable and fully compliant with the USB 3.1
+  Gen 1 specification. The USB5744 also supports Full Speed (FS) and Low Speed
+  (LS) USB signaling, offering complete coverage of all defined USB operating
+  speeds. The new SuperSpeed hubs operate in parallel with the USB 2.0
+  controller, so 5 Gbps SuperSpeed data transfers are not affected by slower
+  USB 2.0 traffic.
+
+maintainers:
+  - Piyush Mehta <[email protected]>
+  - Michal Simek <[email protected]>
+
+properties:
+  compatible:
+    const: microchip,usb5744
+
+  reg:
Quoted 8 lines

Documentation/devicetree/bindings/usb/microchip,usb5744.yaml line 30

Quoted 4 lines
Documentation/devicetree/bindings/usb/microchip,usb5744.yaml new file +4 -0
+    maxItems: 1
+    description: |
+      Specifies the i2c slave address, it is required and should be 0x2d
+      if I2C is used.

If I2C is not used, then this should be underneath the USB host as a USB device. That also implies a different compatible string. I'd suggest you just say I2C is required if that's your use.

We can't say that i2c is required because we have both cases. One is really usb hub connected over i2c which at least requires to send one smbus command to start operate. But it can be extended to add more features - limit speeds, disable ports, etc.

And the second is really the same usb hub without i2c connected which runs in default mode. But reset is required to ensure proper reset sequence.
Hub also have external clock chip which is not handled now because it is just crystal on the board but if you want I can also model it via fixed clock and call clock enable for it.

Quoted 4 lines
Quoted 2 lines

It is the same use case as is with
Documentation/devicetree/bindings/usb/usb3503.txt

Yes, there are examples of how we don't want to do it.

ok.

Quoted 11 lines
Quoted 6 lines

Can you please elaborate why different compatible string should be used? It is still the same device and not quite sure why different compatible string should be used.

Do you also want to example where this node is the part of usb node?

See usb/usb-device.txt. And there is this[1] under review.

For these cases with I2C, I'd really rather see the hub always under the USB bus with a link to the I2C bus when connected.

I read that thread and also looked at his device and it is very similar to this one. Binding should also have information about i2c or spi. It is the same case here that you can use this hub without any bus connected which works in default mode. Or when i2c/smbus is connected and the hub is waiting for initialization sequence. And I expect spi behaves very similarly but don't have this setup here.

Do we have any binding doc which is using suggested bus link?

Thanks,
Michal

_______________________________________________
linux-arm-kernel mailing list
[email protected]
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

maintainer
#6 lore raw

Re: [PATCH v2 1/2] dt-bindings: usb: misc: Add binding for Microchip usb5744 hub

Quoted 97 lines · Michal Simek

Hi Rob,

Quoted 74 lines · Rob Herring
Quoted 73 lines · Michal Simek

Hi Rob,

Quoted 48 lines · Rob Herring
Quoted 47 lines · Michal Simek

From: Piyush Mehta <[email protected]>

Added dt binding for usb5744 driver.

Signed-off-by Piyush Mehta <[email protected]>
Signed-off-by Michal Simek <[email protected]>

---

Changes in v2: None

 .../bindings/usb/microchip,usb5744.yaml       | 56 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 57 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/usb/microchip,usb5744.yaml
Documentation/devicetree/bindings/usb/microchip,usb5744.yaml new file +26 -0
new file mode 100644
index 000000000000..fe222f6db81d
@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/usb/microchip,usb5744.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Bindings for the Microchip USB5744 4-port Hub Controller
+
+description:
+  Microchip’s USB5744 SmartHub™ IC is a 4 port, SuperSpeed (SS)/Hi-Speed (HS),
+  low power, low pin count configurable and fully compliant with the USB 3.1
+  Gen 1 specification. The USB5744 also supports Full Speed (FS) and Low Speed
+  (LS) USB signaling, offering complete coverage of all defined USB operating
+  speeds. The new SuperSpeed hubs operate in parallel with the USB 2.0
+  controller, so 5 Gbps SuperSpeed data transfers are not affected by slower
+  USB 2.0 traffic.
+
+maintainers:
+  - Piyush Mehta <[email protected]>
+  - Michal Simek <[email protected]>
+
+properties:
+  compatible:
+    const: microchip,usb5744
+
+  reg:
Quoted 8 lines

Documentation/devicetree/bindings/usb/microchip,usb5744.yaml line 30

Quoted 4 lines
Documentation/devicetree/bindings/usb/microchip,usb5744.yaml new file +4 -0
+    maxItems: 1
+    description: |
+      Specifies the i2c slave address, it is required and should be 0x2d
+      if I2C is used.

If I2C is not used, then this should be underneath the USB host as a USB device. That also implies a different compatible string. I'd suggest you just say I2C is required if that's your use.

We can't say that i2c is required because we have both cases. One is really usb hub connected over i2c which at least requires to send one smbus command to start operate. But it can be extended to add more features - limit speeds, disable ports, etc.

And the second is really the same usb hub without i2c connected which runs in default mode. But reset is required to ensure proper reset sequence.
Hub also have external clock chip which is not handled now because it is just crystal on the board but if you want I can also model it via fixed clock and call clock enable for it.

Quoted 4 lines
Quoted 2 lines

It is the same use case as is with
Documentation/devicetree/bindings/usb/usb3503.txt

Yes, there are examples of how we don't want to do it.

ok.

Quoted 11 lines
Quoted 6 lines

Can you please elaborate why different compatible string should be used? It is still the same device and not quite sure why different compatible string should be used.

Do you also want to example where this node is the part of usb node?

See usb/usb-device.txt. And there is this[1] under review.

For these cases with I2C, I'd really rather see the hub always under the USB bus with a link to the I2C bus when connected.

Quoted 8 lines

I read that thread and also looked at his device and it is very similar to this one. Binding should also have information about i2c or spi. It is the same case here that you can use this hub without any bus connected which works in default mode. Or when i2c/smbus is connected and the hub is waiting for initialization sequence. And I expect spi behaves very similarly but don't have this setup here.

Do we have any binding doc which is using suggested bus link?

'i2c-bus' or 'ddc-i2c-bus' properties for I2C. Don't think we have anything for SPI, but I'd expect it would be similar though we'd need a cell for the chip-select.

Rob

author
#7 lore raw

PATCH v2 2/2 usb: misc: usb5744: Add support for USB hub controller

In reply to Michal Simek

From: Piyush Mehta <[email protected]>

This patch adds a USB GPIO based hub reset for USB5744 hub. This usb5744 driver trigger hub reset signal after soft reset or core Reset. The HUB needs to be resetted after completion of phy initialization. After the toggling of gpio, hub configure using i2c usb attached command.

USB5744 hub can be used without any I2C connection, is handled by a simple platform device driver.

As part of the reset, sets the direction of the pin to output before toggling the pin. Delay of millisecond is added in between low and high to meet the setup and hold time requirement of the reset.

Signed-off-by Piyush Mehta <[email protected]>
Signed-off-by Michal Simek <[email protected]>

---

Changes in v2:
- s/USB_USB5744/USB_HUB_USB5744/g
- Fix order in Makefile and Kconfig

 MAINTAINERS                |   1 +
 drivers/usb/misc/Kconfig   |   9 +++
 drivers/usb/misc/Makefile  |   1 +
 drivers/usb/misc/usb5744.c | 115 +++++++++++++++++++++++++++++++++++++
 4 files changed, 126 insertions(+)
 create mode 100644 drivers/usb/misc/usb5744.c
MAINTAINERS +1 -0
index 7439471b5d37..56d1fcdd24f6 100644
@@ -2706,6 +2706,7 @@ F:	drivers/edac/synopsys_edac.c
 F:	drivers/i2c/busses/i2c-cadence.c
 F:	drivers/i2c/busses/i2c-xiic.c
 F:	drivers/mmc/host/sdhci-of-arasan.c
+F:	drivers/usb/misc/usb5744.c
 N:	zynq
 N:	xilinx
drivers/usb/misc/Kconfig +9 -0
index 8f1144359012..9995a5701fd9 100644
@@ -255,6 +255,15 @@ config USB_HSIC_USB4604
 	help
 	  This option enables support for SMSC USB4604 HSIC to USB 2.0 Driver.
 
+config USB_HUB_USB5744
+	tristate "Microchip USB5744 Hub driver"
+	depends on I2C
+	depends on GPIOLIB
+	help
+	  This option enables support for Microchip USB5744 Hub. This driver
+	  optionally reset the hub using gpio pin and configure hub via i2c if
+	  connected.
+
 config USB_LINK_LAYER_TEST
 	tristate "USB Link Layer Test driver"
 	help
drivers/usb/misc/Makefile +1 -0
index 5f4e598573ab..fbb9adf08f8c 100644
@@ -27,6 +27,7 @@ obj-$(CONFIG_USB_YUREX)			+= yurex.o
 obj-$(CONFIG_USB_HUB_USB251XB)		+= usb251xb.o
 obj-$(CONFIG_USB_HSIC_USB3503)		+= usb3503.o
 obj-$(CONFIG_USB_HSIC_USB4604)		+= usb4604.o
+obj-$(CONFIG_USB_HUB_USB5744)		+= usb5744.o
 obj-$(CONFIG_USB_CHAOSKEY)		+= chaoskey.o
 
 obj-$(CONFIG_USB_SISUSBVGA)		+= sisusbvga/
drivers/usb/misc/usb5744.c new file +115 -0

115 lines not on this page · raw message

Signature · 7 lines
2.30.0


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#8 lore raw

Re: [PATCH v2 2/2] usb: misc: usb5744: Add support for USB hub controller

Quoted 170 lines · Michal Simek

From: Piyush Mehta <[email protected]>

This patch adds a USB GPIO based hub reset for USB5744 hub. This usb5744 driver trigger hub reset signal after soft reset or core Reset. The HUB needs to be resetted after completion of phy initialization. After the toggling of gpio, hub configure using i2c usb attached command.

USB5744 hub can be used without any I2C connection, is handled by a simple platform device driver.

As part of the reset, sets the direction of the pin to output before toggling the pin. Delay of millisecond is added in between low and high to meet the setup and hold time requirement of the reset.

Signed-off-by Piyush Mehta <[email protected]>
Signed-off-by Michal Simek <[email protected]>

---

Changes in v2:
- s/USB_USB5744/USB_HUB_USB5744/g
- Fix order in Makefile and Kconfig

 MAINTAINERS                |   1 +
 drivers/usb/misc/Kconfig   |   9 +++
 drivers/usb/misc/Makefile  |   1 +
 drivers/usb/misc/usb5744.c | 115 +++++++++++++++++++++++++++++++++++++
 4 files changed, 126 insertions(+)
 create mode 100644 drivers/usb/misc/usb5744.c
MAINTAINERS +1 -0
index 7439471b5d37..56d1fcdd24f6 100644
@@ -2706,6 +2706,7 @@ F:	drivers/edac/synopsys_edac.c
 F:	drivers/i2c/busses/i2c-cadence.c
 F:	drivers/i2c/busses/i2c-xiic.c
 F:	drivers/mmc/host/sdhci-of-arasan.c
+F:	drivers/usb/misc/usb5744.c
 N:	zynq
 N:	xilinx
drivers/usb/misc/Kconfig +9 -0
index 8f1144359012..9995a5701fd9 100644
@@ -255,6 +255,15 @@ config USB_HSIC_USB4604
 	help
 	  This option enables support for SMSC USB4604 HSIC to USB 2.0 Driver.
 
+config USB_HUB_USB5744
+	tristate "Microchip USB5744 Hub driver"
+	depends on I2C
+	depends on GPIOLIB
+	help
+	  This option enables support for Microchip USB5744 Hub. This driver
+	  optionally reset the hub using gpio pin and configure hub via i2c if
+	  connected.
+
 config USB_LINK_LAYER_TEST
 	tristate "USB Link Layer Test driver"
 	help
drivers/usb/misc/Makefile +1 -0
index 5f4e598573ab..fbb9adf08f8c 100644
@@ -27,6 +27,7 @@ obj-$(CONFIG_USB_YUREX)			+= yurex.o
 obj-$(CONFIG_USB_HUB_USB251XB)		+= usb251xb.o
 obj-$(CONFIG_USB_HSIC_USB3503)		+= usb3503.o
 obj-$(CONFIG_USB_HSIC_USB4604)		+= usb4604.o
+obj-$(CONFIG_USB_HUB_USB5744)		+= usb5744.o
 obj-$(CONFIG_USB_CHAOSKEY)		+= chaoskey.o
 
 obj-$(CONFIG_USB_SISUSBVGA)		+= sisusbvga/
drivers/usb/misc/usb5744.c new file +91 -0
new file mode 100644
index 000000000000..729b76345c69
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for the Microchip USB5744 4-port hub.
+ *
+ * Copyright (c) 2021 Xilinx, Inc.
+ */
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/gpio/consumer.h>
+#include <linux/platform_device.h>
+
+static int usb5744_init_hw(struct device *dev)
+{
+	struct gpio_desc *reset_gpio;
+
+	reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(reset_gpio)) {
+		dev_err(dev, "Failed to bind reset gpio");
+		return -ENODEV;
+	}
+
+	if (reset_gpio) {
+		/* Toggle RESET_N to reset the hub. */
+		gpiod_set_value(reset_gpio, 0);
+		usleep_range(5, 20); /* trstia */
+		gpiod_set_value(reset_gpio, 1);
+		usleep_range(5000, 10000); /* tcsh */
+	}
+
+	return 0;
+}
+
+static int usb5744_i2c_probe(struct i2c_client *client,
+			     const struct i2c_device_id *id)
+{
+	struct device *dev = &client->dev;
+	int ret;
+
+	/* Trigger gpio reset to the hub. */
+	ret = usb5744_init_hw(dev);
+	if (ret)
+		return ret;
+
+	/* Send SMBus command to boot hub. */
+	ret = i2c_smbus_write_word_data(client, 0xAA, swab16(0x5600));
+	if (ret < 0)
+		dev_err(dev, "Sending boot command failed");
+
+	return ret;
+}
+
+static int usb5744_platform_probe(struct platform_device *pdev)
+{
+	/* Trigger gpio reset to the hub. */
+	return usb5744_init_hw(&pdev->dev);
+}
+
+static const struct i2c_device_id usb5744_id[] = {
+	{ "usb5744", 0 },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, usb5744_id);
+
+static struct i2c_driver usb5744_i2c_driver = {
+	.driver = {
+		.name = "usb5744",
+	},
+	.probe = usb5744_i2c_probe,
+	.id_table = usb5744_id,
+};
+
+static const struct of_device_id usb5744_platform_id[] = {
+	{ .compatible = "microchip,usb5744", },
+	{ }
+};
+
+static struct platform_driver usb5744_platform_driver = {
+	.driver = {
+		.name = "microchip,usb5744",
+		.of_match_table = usb5744_platform_id,
+	},
+	.probe = usb5744_platform_probe,
+};
+
+static int __init usb5744_init(void)
+{
+	int err;

drivers/usb/misc/usb5744.c line 101

Quoted 10 lines
drivers/usb/misc/usb5744.c new file +10 -0
+
+	err = i2c_add_driver(&usb5744_i2c_driver);
+	if (err != 0)
+		pr_err("usb5744: Failed to register I2C driver: %d\n", err);
+
+	err = platform_driver_register(&usb5744_platform_driver);
+	if (err != 0)
+		pr_err("usb5744: Failed to register platform driver: %d\n",
+		       err);
+	return 0;

So, no matter how many failures happen, you still say everything is good and continue on with loading the module?

Please don't.

thanks,

greg k-h

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