Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756786AbcKVUrR (ORCPT ); Tue, 22 Nov 2016 15:47:17 -0500 Received: from mail-qk0-f175.google.com ([209.85.220.175]:36582 "EHLO mail-qk0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756115AbcKVUrP (ORCPT ); Tue, 22 Nov 2016 15:47:15 -0500 MIME-Version: 1.0 In-Reply-To: References: <20161121163014.28008-1-ahaslam@baylibre.com> <20161121163014.28008-4-ahaslam@baylibre.com> From: Axel Haslam Date: Tue, 22 Nov 2016 21:46:33 +0100 Message-ID: Subject: Re: [PATCH v6 3/5] USB: ohci: da8xx: Allow a regulator to handle VBUS To: David Lechner Cc: Greg KH , Sekhar Nori , Kevin Hilman , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9247 Lines: 277 On Tue, Nov 22, 2016 at 9:37 PM, David Lechner wrote: > On 11/21/2016 10:30 AM, Axel Haslam wrote: >> >> Using a regulator to handle VBUS will eliminate the need for >> platform data and callbacks, and make the driver more generic >> allowing different types of regulators to handle VBUS. >> >> 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 >> --- >> drivers/usb/host/ohci-da8xx.c | 97 >> +++++++++++++++++++++++++++++++++++++++++-- >> 1 file changed, 94 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/usb/host/ohci-da8xx.c b/drivers/usb/host/ohci-da8xx.c >> index 90763ad..d0eb754 100644 >> --- a/drivers/usb/host/ohci-da8xx.c >> +++ b/drivers/usb/host/ohci-da8xx.c >> @@ -20,6 +20,7 @@ >> #include >> #include >> #include >> +#include >> #include >> #include >> #include >> @@ -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 reg_enabled; >> }; >> >> #define to_da8xx_ohci(hcd) (struct da8xx_ohci_hcd >> *)(hcd_to_ohci(hcd)->priv) >> @@ -83,56 +88,103 @@ 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->reg_enabled) { >> + ret = regulator_enable(da8xx_ohci->vbus_reg); >> + if (ret) { >> + dev_err(dev, "Failed to enable regulator: %d\n", >> ret); >> + return ret; >> + } >> + da8xx_ohci->reg_enabled = 1; >> + >> + } else if (!on && da8xx_ohci->reg_enabled) { >> + ret = regulator_disable(da8xx_ohci->vbus_reg); >> + if (ret) { >> + dev_err(dev, "Failed to disable regulator: %d\n", >> ret); >> + return ret; >> + } >> + da8xx_ohci->reg_enabled = 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) >> + 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; >> } >> >> @@ -160,15 +212,41 @@ 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; > > > Following up from a v5 thread that is still applicable here, Axel said: > >> I did a couple of tests, and i don't get those prints do you get them?. > > The problem here is that ocic_mask |= 1; is wrong. It needs to be... > > ocic_mask |= (1 << 1); > i see, i will fix it thanks! > If you look at the other uses of ocic_mask, you will see why this it needs > to be this way. Once you make this change, then you will see this in the > kernel log: > > usb 1-1: USB disconnect, device number 2 > usb 1-1: may be reset is needed?.. > ohci ohci: over current event > usb usb1-port1: over-current condition > > So, we don't need the dev_warn() here. agree! > > > More from Axel: > >> What i understand is that they happen when we get a hub event that is >> reporting the over current. Which is what the root hub of the davinci >> system >> does not have, and why we use gpios instead). > > Even though the hardware is not capable of detecting the overcurrent by > itself, we are poking the registers in ohci_da8xx_hub_control(), so the core > hub driver sees it just the same as if the hardware itself changed the > register. > > >> + 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) { >> + 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); >> + } >> >> - if (hub && hub->ocic_notify) >> - return hub->ocic_notify(ohci_da8xx_ocic_handler); >> + if (ret) >> + dev_err(dev, "Failed to register notifier: %d\n", ret); >> >> - return 0; >> + return ret; >> } >> >> static void ohci_da8xx_unregister_notify(struct usb_hcd *hcd) >> @@ -331,6 +409,7 @@ 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)) { >> @@ -348,6 +427,18 @@ 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 { > > > It might be good to skip the dev_err() if we get -EPROBE_DEFER > >> + dev_err(&pdev->dev, >> + "Failed to get regulator\n"); >> + goto err; >> + } >> + } >> + >> mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); >> hcd->regs = devm_ioremap_resource(&pdev->dev, mem); >> if (IS_ERR(hcd->regs)) { >> >