[PATCH v6 3/4] usb: ohci-exynos: Add facility to use phy provided by the generic phy framework
Vivek Gautam
gautam.vivek at samsung.com
Sun May 4 22:02:57 PDT 2014
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 at samsung.com>
Cc: Jingoo Han <jg1.han at samsung.com>
Acked-by: Alan Stern <stern at rowland.harvard.edu>
Acked-by: Kukjin Kim <kgene.kim at samsung.com>
---
Changes from v5:
- Removed setting phy explicitly to error pointer.
- Changed error check to '-ENOSYS' instead of '-ENXIO' in failure case of
devm_of_phy_get().
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 | 118 +++++++++++++++++---
2 files changed, 118 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 at 12120000 {
@@ -47,6 +54,15 @@ Example:
clocks = <&clock 285>;
clock-names = "usbhost";
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+ port at 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..32f2ff1 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 +34,110 @@ 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");
+ } 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 != -ENOSYS && ret != -ENODEV) {
+ dev_err(dev, "no usb2 phy configured\n");
+ return ret;
+ }
+ dev_dbg(dev, "Failed to get usb2 phy\n");
+ }
+ exynos_ohci->phy_g[phy_number] = phy;
+ }
+
+ return ret;
+}
+
+static int exynos_ohci_phy_enable(struct device *dev)
{
struct usb_hcd *hcd = dev_get_drvdata(dev);
struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
+ int i;
+ int ret = 0;
+
+ if (!IS_ERR(exynos_ohci->phy))
+ return usb_phy_init(exynos_ohci->phy);
- if (exynos_ohci->phy)
- usb_phy_init(exynos_ohci->phy);
+ for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
+ if (!IS_ERR(exynos_ohci->phy_g[i]))
+ ret = phy_power_on(exynos_ohci->phy_g[i]);
+ if (ret)
+ for (i--; i >= 0; i--)
+ if (!IS_ERR(exynos_ohci->phy_g[i]))
+ phy_power_off(exynos_ohci->phy_g[i]);
+
+ return ret;
}
static void exynos_ohci_phy_disable(struct device *dev)
{
struct usb_hcd *hcd = dev_get_drvdata(dev);
struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
+ int i;
- if (exynos_ohci->phy)
+ if (!IS_ERR(exynos_ohci->phy)) {
usb_phy_shutdown(exynos_ohci->phy);
+ return;
+ }
+
+ for (i = 0; i < PHY_NUMBER; i++)
+ if (!IS_ERR(exynos_ohci->phy_g[i]))
+ phy_power_off(exynos_ohci->phy_g[i]);
}
static int exynos_ohci_probe(struct platform_device *pdev)
@@ -62,7 +145,6 @@ 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;
int irq;
int err;
@@ -88,15 +170,9 @@ 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;
- } else {
- exynos_ohci->phy = phy;
- exynos_ohci->otg = phy->otg;
- }
+ err = exynos_ohci_get_phy(&pdev->dev, exynos_ohci);
+ if (err)
+ goto fail_clk;
skip_phy:
exynos_ohci->clk = devm_clk_get(&pdev->dev, "usbhost");
@@ -139,7 +215,11 @@ skip_phy:
platform_set_drvdata(pdev, hcd);
- exynos_ohci_phy_enable(&pdev->dev);
+ err = exynos_ohci_phy_enable(&pdev->dev);
+ if (err) {
+ dev_err(&pdev->dev, "Failed to enable USB phy\n");
+ goto fail_io;
+ }
err = usb_add_hcd(hcd, irq, IRQF_SHARED);
if (err) {
@@ -210,13 +290,19 @@ 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);
+ int ret;
clk_prepare_enable(exynos_ohci->clk);
if (exynos_ohci->otg)
exynos_ohci->otg->set_host(exynos_ohci->otg, &hcd->self);
- exynos_ohci_phy_enable(dev);
+ ret = exynos_ohci_phy_enable(dev);
+ if (ret) {
+ dev_err(dev, "Failed to enable USB phy\n");
+ clk_disable_unprepare(exynos_ohci->clk);
+ return ret;
+ }
ohci_resume(hcd, false);
--
1.7.10.4
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