Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754048AbaJ1Qjv (ORCPT ); Tue, 28 Oct 2014 12:39:51 -0400 Received: from mail-qc0-f180.google.com ([209.85.216.180]:32890 "EHLO mail-qc0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753342AbaJ1Qjs (ORCPT ); Tue, 28 Oct 2014 12:39:48 -0400 MIME-Version: 1.0 In-Reply-To: <1414497280-3126-5-git-send-email-ray.huang@amd.com> References: <1414497280-3126-1-git-send-email-ray.huang@amd.com> <1414497280-3126-5-git-send-email-ray.huang@amd.com> From: Bjorn Helgaas Date: Tue, 28 Oct 2014 10:39:26 -0600 Message-ID: Subject: Re: [PATCH v3 04/19] usb: dwc3: add disscramble quirk To: Huang Rui Cc: Felipe Balbi , Alan Stern , Greg Kroah-Hartman , Paul Zimmerman , Heikki Krogerus , Jason Chang , Vincent Wan , Tony Li , USB list , "linux-pci@vger.kernel.org" , "linux-kernel@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 On Tue, Oct 28, 2014 at 5:54 AM, Huang Rui wrote: > This patch adds disscramble quirk, and it only needs to be enabled at fpga "disscramble" (in subject and above) is not a real word. I see that DWC3_GCTL_DISSCRAMBLE is already defined in drivers/usb/dwc3/core.h even before your patches, so I suppose it's something the hardware designers made up. Maybe it means "descramble" (or "unscramble"). Or maybe it means "disable scrambling"? A comment might make this clearer. A better name would be even better. > board on some vendor platforms. > > Signed-off-by: Huang Rui > --- > drivers/usb/dwc3/core.c | 14 +++++++++++++- > drivers/usb/dwc3/core.h | 3 +++ > drivers/usb/dwc3/platform_data.h | 2 ++ > 3 files changed, 18 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c > index ddac372..c320835 100644 > --- a/drivers/usb/dwc3/core.c > +++ b/drivers/usb/dwc3/core.c > @@ -422,7 +422,6 @@ static int dwc3_core_init(struct dwc3 *dwc) > > reg = dwc3_readl(dwc->regs, DWC3_GCTL); > reg &= ~DWC3_GCTL_SCALEDOWN_MASK; > - reg &= ~DWC3_GCTL_DISSCRAMBLE; > > switch (DWC3_GHWPARAMS1_EN_PWROPT(dwc->hwparams.hwparams1)) { > case DWC3_GHWPARAMS1_EN_PWROPT_CLK: > @@ -461,6 +460,14 @@ static int dwc3_core_init(struct dwc3 *dwc) > dwc->is_fpga = true; > } > > + WARN_ONCE(dwc->disable_scramble_quirk && !dwc->is_fpga, > + "disable_scramble cannot be used on non-FPGA builds\n"); > + > + if (dwc->disable_scramble_quirk && dwc->is_fpga) > + reg |= DWC3_GCTL_DISSCRAMBLE; > + else > + reg &= ~DWC3_GCTL_DISSCRAMBLE; > + > /* > * WORKAROUND: DWC3 revisions <1.90a have a bug > * where the device can fail to connect at SuperSpeed > @@ -705,11 +712,16 @@ static int dwc3_probe(struct platform_device *pdev) > > dwc->needs_fifo_resize = of_property_read_bool(node, "tx-fifo-resize"); > dwc->dr_mode = of_usb_get_dr_mode(node); > + > + dwc->disable_scramble_quirk = of_property_read_bool(node, > + "snps,disable_scramble_quirk"); > } else if (pdata) { > dwc->maximum_speed = pdata->maximum_speed; > > dwc->needs_fifo_resize = pdata->tx_fifo_resize; > dwc->dr_mode = pdata->dr_mode; > + > + dwc->disable_scramble_quirk = pdata->disable_scramble_quirk; > } > > /* default to superspeed if no maximum_speed passed */ > diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h > index f6ee623..56bada6 100644 > --- a/drivers/usb/dwc3/core.h > +++ b/drivers/usb/dwc3/core.h > @@ -672,6 +672,7 @@ struct dwc3_scratchpad_array { > * @setup_packet_pending: true when there's a Setup Packet in FIFO. Workaround > * @start_config_issued: true when StartConfig command has been issued > * @three_stage_setup: set if we perform a three phase setup > + * @disable_scramble_quirk: set if we enable the disable scramble quirk > */ > struct dwc3 { > struct usb_ctrlrequest *ctrl_req; > @@ -776,6 +777,8 @@ struct dwc3 { > unsigned setup_packet_pending:1; > unsigned start_config_issued:1; > unsigned three_stage_setup:1; > + > + unsigned disable_scramble_quirk:1; > }; > > /* -------------------------------------------------------------------------- */ > diff --git a/drivers/usb/dwc3/platform_data.h b/drivers/usb/dwc3/platform_data.h > index 7db34f0..9209d02 100644 > --- a/drivers/usb/dwc3/platform_data.h > +++ b/drivers/usb/dwc3/platform_data.h > @@ -24,4 +24,6 @@ struct dwc3_platform_data { > enum usb_device_speed maximum_speed; > enum usb_dr_mode dr_mode; > bool tx_fifo_resize; > + > + unsigned disable_scramble_quirk:1; > }; > -- > 1.9.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/