[PATCH v4 3/3] USB: ohci: da8xx: Allow a regulator to handle VBUS

From: Axel Haslam
Date: Tue Nov 08 2016 - 13:58:16 EST


We need to remove the platform callbacks to be able to probe
the driver using device tree. Using a regulator to handle VBUS will
eliminate the need for these callbacks once all users are converted
to use a regulator.

The regulator equivalents to the platform callbacks are:
set_power -> regulator_enable/regulator_disable
get_power -> regulator_is_enabled
get_oci -> regulator_get_error_flags
ocic_notify -> regulator event notification

Signed-off-by: Axel Haslam <ahaslam@xxxxxxxxxxxx>
---
drivers/usb/host/ohci-da8xx.c | 97 ++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 95 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/ohci-da8xx.c b/drivers/usb/host/ohci-da8xx.c
index 9ed43c7..0a4b885 100644
--- a/drivers/usb/host/ohci-da8xx.c
+++ b/drivers/usb/host/ohci-da8xx.c
@@ -20,6 +20,7 @@
#include <linux/platform_device.h>
#include <linux/phy/phy.h>
#include <linux/platform_data/usb-davinci.h>
+#include <linux/regulator/consumer.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include <asm/unaligned.h>
@@ -36,8 +37,12 @@ static int (*orig_ohci_hub_control)(struct usb_hcd *hcd, u16 typeReq,
static int (*orig_ohci_hub_status_data)(struct usb_hcd *hcd, char *buf);

struct da8xx_ohci_hcd {
+ struct usb_hcd *hcd;
struct clk *usb11_clk;
struct phy *usb11_phy;
+ struct regulator *vbus_reg;
+ struct notifier_block nb;
+ unsigned int is_powered;
};
#define to_da8xx_ohci(hcd) (struct da8xx_ohci_hcd *)(hcd_to_ohci(hcd)->priv)

@@ -82,56 +87,105 @@ static void ohci_da8xx_disable(struct usb_hcd *hcd)

static int ohci_da8xx_set_power(struct usb_hcd *hcd, int on)
{
+ struct da8xx_ohci_hcd *da8xx_ohci = to_da8xx_ohci(hcd);
struct device *dev = hcd->self.controller;
struct da8xx_ohci_root_hub *hub = dev_get_platdata(dev);
+ int ret;

if (hub && hub->set_power)
return hub->set_power(1, on);

+ if (!da8xx_ohci->vbus_reg)
+ return 0;
+
+ if (on && !da8xx_ohci->is_powered) {
+ ret = regulator_enable(da8xx_ohci->vbus_reg);
+ if (ret) {
+ dev_err(dev, "Fail to enable regulator: %d\n", ret);
+ return ret;
+ }
+ da8xx_ohci->is_powered = 1;
+
+ } else if (!on && da8xx_ohci->is_powered) {
+ ret = regulator_disable(da8xx_ohci->vbus_reg);
+ if (ret) {
+ dev_err(dev, "Fail to disable regulator: %d\n", ret);
+ return ret;
+ }
+ da8xx_ohci->is_powered = 0;
+ }
+
return 0;
}

static int ohci_da8xx_get_power(struct usb_hcd *hcd)
{
+ struct da8xx_ohci_hcd *da8xx_ohci = to_da8xx_ohci(hcd);
struct device *dev = hcd->self.controller;
struct da8xx_ohci_root_hub *hub = dev_get_platdata(dev);

if (hub && hub->get_power)
return hub->get_power(1);

+ if (da8xx_ohci->vbus_reg)
+ return regulator_is_enabled(da8xx_ohci->vbus_reg);
+
return 1;
}

static int ohci_da8xx_get_oci(struct usb_hcd *hcd)
{
+ struct da8xx_ohci_hcd *da8xx_ohci = to_da8xx_ohci(hcd);
struct device *dev = hcd->self.controller;
struct da8xx_ohci_root_hub *hub = dev_get_platdata(dev);
+ unsigned int flags;
+ int ret;

if (hub && hub->get_oci)
return hub->get_oci(1);

+ if (!da8xx_ohci->vbus_reg)
+ return 0;
+
+ ret = regulator_get_error_flags(da8xx_ohci->vbus_reg, &flags);
+ if (ret) {
+ dev_err(dev, "could not get regulator error flags: %d\n", ret);
+ return ret;
+ }
+
+ if (flags && REGULATOR_ERROR_OVER_CURRENT)
+ return 1;
+
return 0;
}

static int ohci_da8xx_has_set_power(struct usb_hcd *hcd)
{
+ struct da8xx_ohci_hcd *da8xx_ohci = to_da8xx_ohci(hcd);
struct device *dev = hcd->self.controller;
struct da8xx_ohci_root_hub *hub = dev_get_platdata(dev);

if (hub && hub->set_power)
return 1;

+ if (da8xx_ohci->vbus_reg)
+ return 1;
+
return 0;
}

static int ohci_da8xx_has_oci(struct usb_hcd *hcd)
{
+ struct da8xx_ohci_hcd *da8xx_ohci = to_da8xx_ohci(hcd);
struct device *dev = hcd->self.controller;
struct da8xx_ohci_root_hub *hub = dev_get_platdata(dev);

if (hub && hub->get_oci)
return 1;

+ if (da8xx_ohci->vbus_reg)
+ return 1;
+
return 0;
}

@@ -159,15 +213,41 @@ static void ohci_da8xx_ocic_handler(struct da8xx_ohci_root_hub *hub,
hub->set_power(port, 0);
}

+static int ohci_da8xx_regulator_event(struct notifier_block *nb,
+ unsigned long event, void *data)
+{
+ struct da8xx_ohci_hcd *da8xx_ohci =
+ container_of(nb, struct da8xx_ohci_hcd, nb);
+ struct device *dev = da8xx_ohci->hcd->self.controller;
+
+ if (event & REGULATOR_EVENT_OVER_CURRENT) {
+ dev_warn(dev, "over current event\n");
+ ocic_mask |= 1;
+ ohci_da8xx_set_power(da8xx_ohci->hcd, 0);
+ }
+
+ return 0;
+}
+
static int ohci_da8xx_register_notify(struct usb_hcd *hcd)
{
+ struct da8xx_ohci_hcd *da8xx_ohci = to_da8xx_ohci(hcd);
struct device *dev = hcd->self.controller;
struct da8xx_ohci_root_hub *hub = dev_get_platdata(dev);
+ int ret = 0;

if (hub && hub->ocic_notify)
- return hub->ocic_notify(ohci_da8xx_ocic_handler);
+ ret = hub->ocic_notify(ohci_da8xx_ocic_handler);
+ else if (da8xx_ohci->vbus_reg) {
+ da8xx_ohci->nb.notifier_call = ohci_da8xx_regulator_event;
+ ret = devm_regulator_register_notifier(da8xx_ohci->vbus_reg,
+ &da8xx_ohci->nb);
+ }

- return 0;
+ if (ret)
+ dev_err(dev, "Failed to register notifier: %d\n", ret);
+
+ return ret;
}

static void ohci_da8xx_unregister_notify(struct usb_hcd *hcd)
@@ -330,6 +410,7 @@ static int ohci_da8xx_probe(struct platform_device *pdev)
return -ENOMEM;

da8xx_ohci = to_da8xx_ohci(hcd);
+ da8xx_ohci->hcd = hcd;

da8xx_ohci->usb11_clk = devm_clk_get(&pdev->dev, "usb11");
if (IS_ERR(da8xx_ohci->usb11_clk)) {
@@ -347,6 +428,18 @@ static int ohci_da8xx_probe(struct platform_device *pdev)
goto err;
}

+ da8xx_ohci->vbus_reg = devm_regulator_get_optional(&pdev->dev, "vbus");
+ if (IS_ERR(da8xx_ohci->vbus_reg)) {
+ error = PTR_ERR(da8xx_ohci->vbus_reg);
+ if (error == -ENODEV)
+ da8xx_ohci->vbus_reg = NULL;
+ else {
+ dev_err(&pdev->dev,
+ "Failed to get regulator: %d\n", error);
+ goto err;
+ }
+ }
+
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
hcd->regs = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(hcd->regs)) {
--
2.10.1