[PATCH] usb: ohci-exynos: Add facility to use phy provided by the generic phy framework

From: Vivek Gautam
Date: Thu Apr 10 2014 - 09:26:08 EST


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>
Cc: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
---

Based on 'usb-next' branch of Greg's usb tree.
Tested with local dt patches, similar to ehci dt changes posted by Kamil[1].
Tested on Exynos5250 smdk.

[1] [PATCH v6 4/8] dts: Add usb2phy to Exynos 5250
https://lkml.org/lkml/2014/1/29/302

.../devicetree/bindings/usb/exynos-usb.txt | 14 ++++
drivers/usb/host/ohci-exynos.c | 79 ++++++++++++++++++--
2 files changed, 85 insertions(+), 8 deletions(-)

diff --git a/Documentation/devicetree/bindings/usb/exynos-usb.txt b/Documentation/devicetree/bindings/usb/exynos-usb.txt
index d967ba1..ef0bc09 100644
--- a/Documentation/devicetree/bindings/usb/exynos-usb.txt
+++ b/Documentation/devicetree/bindings/usb/exynos-usb.txt
@@ -38,6 +38,10 @@ 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 its reg entry with a consecutive
+number. Also it should contain phys and phy-names entries specifying the
+phy used by the port.

Example:
usb@12120000 {
@@ -47,6 +51,16 @@ Example:

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

DWC3
diff --git a/drivers/usb/host/ohci-exynos.c b/drivers/usb/host/ohci-exynos.c
index 68588d8..52eb821 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>
@@ -37,6 +38,7 @@ struct exynos_ohci_hcd {
struct clk *clk;
struct usb_phy *phy;
struct usb_otg *otg;
+ struct phy *phy_g;
};

static void exynos_ohci_phy_enable(struct platform_device *pdev)
@@ -57,12 +59,26 @@ static void exynos_ohci_phy_disable(struct platform_device *pdev)
usb_phy_shutdown(exynos_ohci->phy);
}

+static int exynos_ohci_phyg_on(struct phy *phy, bool on)
+{
+ int ret = 0;
+
+ if (phy) {
+ if (on)
+ ret = phy_power_on(phy);
+ else
+ ret = phy_power_off(phy);
+ }
+
+ return ret;
+}
+
static int exynos_ohci_probe(struct platform_device *pdev)
{
struct exynos_ohci_hcd *exynos_ohci;
struct usb_hcd *hcd;
struct resource *res;
- struct usb_phy *phy;
+ struct device_node *child;
int irq;
int err;

@@ -88,16 +104,49 @@ static int exynos_ohci_probe(struct platform_device *pdev)
"samsung,exynos5440-ohci"))
goto skip_phy;

- phy = devm_usb_get_phy(&pdev->dev, USB_PHY_TYPE_USB2);
- if (IS_ERR(phy)) {
- usb_put_hcd(hcd);
- dev_warn(&pdev->dev, "no platform data or transceiver defined\n");
- return -EPROBE_DEFER;
+ exynos_ohci->phy = devm_usb_get_phy(&pdev->dev, USB_PHY_TYPE_USB2);
+ if (IS_ERR(exynos_ohci->phy)) {
+ err = PTR_ERR(exynos_ohci->phy);
+ if (err == -ENXIO || err == -ENODEV) {
+ exynos_ohci->phy = NULL;
+ } else if (err == -EPROBE_DEFER) {
+ usb_put_hcd(hcd);
+ return err;
+ } else {
+ dev_err(&pdev->dev, "no usb2 phy configured\n");
+ usb_put_hcd(hcd);
+ return err;
+ }
} else {
- exynos_ohci->phy = phy;
- exynos_ohci->otg = phy->otg;
+ 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 that in absence of supporting dts
+ * changes the functionality doesn't break.
+ * Once we move the ohci dt nodes to use new generic phys,
+ * we can remove support for older PHY in this driver.
+ */
+ child = of_get_next_child(pdev->dev.of_node, NULL);
+ exynos_ohci->phy_g = devm_of_phy_get(&pdev->dev, child, 0);
+ of_node_put(child);
+ if (IS_ERR(exynos_ohci->phy_g)) {
+ err = PTR_ERR(exynos_ohci->phy_g);
+ if (err == -ENOSYS || err == -ENODEV) {
+ exynos_ohci->phy_g = NULL;
+ } else if (err == -EPROBE_DEFER) {
+ usb_put_hcd(hcd);
+ return err;
+ } else {
+ dev_err(&pdev->dev, "no usb2 phy configured\n");
+ usb_put_hcd(hcd);
+ return err;
+ }
+ }
+
+ if (!exynos_ohci->phy && !exynos_ohci->phy_g)
+ dev_dbg(&pdev->dev, "Failed to get usb2 phy\n");
skip_phy:
exynos_ohci->clk = devm_clk_get(&pdev->dev, "usbhost");

@@ -140,6 +189,11 @@ skip_phy:
platform_set_drvdata(pdev, hcd);

exynos_ohci_phy_enable(pdev);
+ err = exynos_ohci_phyg_on(exynos_ohci->phy_g, true);
+ if (err) {
+ dev_err(&pdev->dev, "Failed to enable phy\n");
+ goto fail_io;
+ }

err = usb_add_hcd(hcd, irq, IRQF_SHARED);
if (err) {
@@ -151,6 +205,7 @@ skip_phy:

fail_add_hcd:
exynos_ohci_phy_disable(pdev);
+ exynos_ohci_phyg_on(exynos_ohci->phy_g, false);
fail_io:
clk_disable_unprepare(exynos_ohci->clk);
fail_clk:
@@ -169,6 +224,7 @@ static int exynos_ohci_remove(struct platform_device *pdev)
exynos_ohci->otg->set_host(exynos_ohci->otg, &hcd->self);

exynos_ohci_phy_disable(pdev);
+ exynos_ohci_phyg_on(exynos_ohci->phy_g, false);

clk_disable_unprepare(exynos_ohci->clk);

@@ -205,6 +261,7 @@ static int exynos_ohci_suspend(struct device *dev)
exynos_ohci->otg->set_host(exynos_ohci->otg, &hcd->self);

exynos_ohci_phy_disable(pdev);
+ exynos_ohci_phyg_on(exynos_ohci->phy_g, false);

clk_disable_unprepare(exynos_ohci->clk);

@@ -218,6 +275,7 @@ static int exynos_ohci_resume(struct device *dev)
struct usb_hcd *hcd = dev_get_drvdata(dev);
struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
struct platform_device *pdev = to_platform_device(dev);
+ int ret;

clk_prepare_enable(exynos_ohci->clk);

@@ -225,6 +283,11 @@ static int exynos_ohci_resume(struct device *dev)
exynos_ohci->otg->set_host(exynos_ohci->otg, &hcd->self);

exynos_ohci_phy_enable(pdev);
+ ret = exynos_ohci_phyg_on(exynos_ohci->phy_g, true);
+ if (ret) {
+ dev_err(dev, "Failed to enable phy\n");
+ return ret;
+ }

ohci_resume(hcd, false);

--
1.7.10.4

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