Re: [PATCH v5 3/4] usb: ohci-exynos: Add facility to use phy provided by the generic phy framework

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




Hi Vivek,

This looks much better, but there still are some issues. Please see my comments inline.

On 02.05.2014 14:47, Vivek Gautam wrote:
Add support to consume phy provided by Generic phy framework.
Keeping the support for older usb-phy intact right now, in order
to prevent any functionality break in absence of relevant
device tree side change for ohci-exynos.
Once we move to new phy in the device nodes for ohci, we can
remove the support for older phys.

Signed-off-by: Vivek Gautam <gautam.vivek@xxxxxxxxxxx>
Cc: Jingoo Han <jg1.han@xxxxxxxxxxx>
Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
---

Changes from v4:
  - Removed 'phy-names' property from the bindings since we don't need it.
  - Restructured exynos_ohci_get_phy() function to handle error codes as
    well as return relevant error codes effectively.
  - Added IS_ERR() check for PHYs in exynos_ohci_phy_enable()/disable().

Changes from v3:
  - Calling usb_phy_shutdown() when exynos_ohci_phy_enable() is failing.
  - Made exynos_ohci_phy_disable() return void, since its return value
    did not serve any purpose.
  - Calling clk_disable_unprepare() in exynos_ohci_resume() when
    exynos_ohci_phy_enable() is failed.

  .../devicetree/bindings/usb/exynos-usb.txt         |   16 +++
  drivers/usb/host/ohci-exynos.c                     |  120 +++++++++++++++++---
  2 files changed, 120 insertions(+), 16 deletions(-)

diff --git a/Documentation/devicetree/bindings/usb/exynos-usb.txt b/Documentation/devicetree/bindings/usb/exynos-usb.txt
index d967ba1..49a9c6f 100644
--- a/Documentation/devicetree/bindings/usb/exynos-usb.txt
+++ b/Documentation/devicetree/bindings/usb/exynos-usb.txt
@@ -38,6 +38,13 @@ Required properties:
   - interrupts: interrupt number to the cpu.
   - clocks: from common clock binding: handle to usb clock.
   - clock-names: from common clock binding: Shall be "usbhost".
+ - port: if in the SoC there are OHCI phys, they should be listed here.
+   One phy per port. Each port should have following entries:
+	- reg: port number on OHCI controller, e.g
+	       On Exynos5250, port 0 is USB2.0 otg phy
+			      port 1 is HSIC phy0
+			      port 2 is HSIC phy1
+	- phys: from the *Generic PHY* bindings, specifying phy used by port.

  Example:
  	usb@12120000 {
@@ -47,6 +54,15 @@ Example:

  		clocks = <&clock 285>;
  		clock-names = "usbhost";
+
+		#address-cells = <1>;
+		#size-cells = <0>;
+		port@0 {
+		    reg = <0>;
+		    phys = <&usb2phy 1>;
+		    status = "disabled";
+		};
+
  	};

  DWC3
diff --git a/drivers/usb/host/ohci-exynos.c b/drivers/usb/host/ohci-exynos.c
index 05f00e3..e66d391 100644
--- a/drivers/usb/host/ohci-exynos.c
+++ b/drivers/usb/host/ohci-exynos.c
@@ -18,6 +18,7 @@
  #include <linux/module.h>
  #include <linux/of.h>
  #include <linux/platform_device.h>
+#include <linux/phy/phy.h>
  #include <linux/usb/phy.h>
  #include <linux/usb/samsung_usb_phy.h>
  #include <linux/usb.h>
@@ -33,28 +34,112 @@ static struct hc_driver __read_mostly exynos_ohci_hc_driver;

  #define to_exynos_ohci(hcd) (struct exynos_ohci_hcd *)(hcd_to_ohci(hcd)->priv)

+#define PHY_NUMBER 3
+
  struct exynos_ohci_hcd {
  	struct clk *clk;
  	struct usb_phy *phy;
  	struct usb_otg *otg;
+	struct phy *phy_g[PHY_NUMBER];
  };

-static void exynos_ohci_phy_enable(struct device *dev)
+static int exynos_ohci_get_phy(struct device *dev,
+				struct exynos_ohci_hcd *exynos_ohci)
+{
+	struct device_node *child;
+	struct phy *phy;
+	int phy_number;
+	int ret = 0;
+
+	exynos_ohci->phy = devm_usb_get_phy(dev, USB_PHY_TYPE_USB2);
+	if (IS_ERR(exynos_ohci->phy)) {
+		ret = PTR_ERR(exynos_ohci->phy);
+		if (ret != -ENXIO && ret != -ENODEV) {
+			dev_err(dev, "no usb2 phy configured\n");
+			return ret;
+		}
+		dev_dbg(dev, "Failed to get usb2 phy\n");
+		exynos_ohci->phy = ERR_PTR(-ENODEV);

Here you already have exynos_ohci->phy set to an ERR_PTR() value, which was returned by devm_usb_get_phy(). There is no need to overwrite it.

+	} else {
+		exynos_ohci->otg = exynos_ohci->phy->otg;
+	}
+
+	/*
+	 * Getting generic phy:
+	 * We are keeping both types of phys as a part of transiting OHCI
+	 * to generic phy framework, so as to maintain backward compatibilty
+	 * with old DTB.
+	 * If there are existing devices using DTB files built from them,
+	 * to remove the support for old bindings in this driver,
+	 * we need to make sure that such devices have their DTBs
+	 * updated to ones built from new DTS.
+	 */
+	for_each_available_child_of_node(dev->of_node, child) {
+		ret = of_property_read_u32(child, "reg", &phy_number);
+		if (ret) {
+			dev_err(dev, "Failed to parse device tree\n");
+			of_node_put(child);
+			return ret;
+		}
+
+		if (phy_number >= PHY_NUMBER) {
+			dev_err(dev, "Invalid number of PHYs\n");
+			of_node_put(child);
+			return -EINVAL;
+		}
+
+		phy = devm_of_phy_get(dev, child, 0);
+		of_node_put(child);
+		if (IS_ERR(phy)) {
+			ret = PTR_ERR(phy);
+			if (ret != -ENXIO && ret != -ENODEV) {

Shouldn't this be -ENOSYS instead of -ENXIO? At least this is the error code I can see in the stubs provided in include/linux/phy/phy.h.

+				dev_err(dev, "no usb2 phy configured\n");
+				return ret;
+			}
+			dev_dbg(dev, "Failed to get usb2 phy\n");
+			phy = ERR_PTR(-ENODEV);

phy is already an ERR_PTR() here, as returned by devm_of_phy_get().

I guess the same comments apply to patch 4/4.

Best regards,
Tomasz
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]
  Powered by Linux