Re: [PATCH v2 3/5] usb: dwc3: Add quirk for Synopsis device disconnection errata

Felipe Balbi
2015-01-23T16:21:19Z

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Hi,

On Wed, Jan 21, 2015 at 05:02:57PM +0800, Sneeker Yeh wrote:
> Hi Felipe:
>
> Thanks for reviewing these,
>
> 2015-01-19 22:50 GMT+08:00 Felipe Balbi <balbi@ti.com>:
> > Hi,
> >
> > On Mon, Jan 19, 2015 at 03:56:47PM +0800, Sneeker Yeh wrote:
> >> Synopsis Designware USB3 IP earlier than v3.00a which is configured in silicon
> >> with DWC_USB3_SUSPEND_ON_DISCONNECT_EN=1, would need a specific quirk to prevent
> >> xhci host controller from dying when device is disconnected.
> >>
> >> Since DWC_USB3_SUSPEND_ON_DISCONNECT_EN is an IP configuration whose state
> >> cannot be checked from software in runtime, it has to be enabled via platform
> >> data or device tree.
> >>
> >> Signed-off-by: Sneeker Yeh <Sneeker.Yeh@tw.fujitsu.com>
> >> ---
> >> Documentation/devicetree/bindings/usb/dwc3.txt | 17 +++++++++++++++++
> >> drivers/usb/dwc3/core.c | 6 ++++++
> >> drivers/usb/dwc3/core.h | 1 +
> >> drivers/usb/dwc3/host.c | 4 ++++
> >> drivers/usb/dwc3/platform_data.h | 1 +
> >> 5 files changed, 29 insertions(+)
> >>
> >> diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
> >> index cd7f045..1b78b29 100644
> >> --- a/Documentation/devicetree/bindings/usb/dwc3.txt
> >> +++ b/Documentation/devicetree/bindings/usb/dwc3.txt
> >> @@ -37,6 +37,23 @@ Optional properties:
> >> - snps,is-utmi-l1-suspend: true when DWC3 asserts output signal
> >> utmi_l1_suspend_n, false when asserts utmi_sleep_n
> >> - snps,hird-threshold: HIRD threshold
> >> + - snps,has_suspend_on_disconnect: true when IP is configured in silicon with
> >> + DWC_USB3_SUSPEND_ON_DISCONNECT_EN=1, it can inject a
> >> + specific quirk to prevent xhci host controller from
> >> + dying when usb device is disconnected from root hub.
> >> + Since DWC_USB3_SUSPEND_ON_DISCONNECT_EN is an IP
> >> + configuration whose state cannot be checked from
> >> + software in runtime, it has to be enabled via platform
> >> + data or device tree.
> >> +
> >> + xhci host dying symptom here is caused by that
> >> + DWC_USB3_SUSPEND_ON_DISCONNECT_EN=1
> >> + configuration makes IP auto-suspended after PORTCSC is
> >> + cleared when usb device detached, then an asynchronous
> >> + disconnection procedure might fail using endpoint
> >> + command that suspened IP won't have any response to.
> >> +
> >> + this issue is fixed when IP version >= 3.00a.
> >>
> >> This is usually a subnode to DWC3 glue to which it is connected.
> >>
> >> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> >> index 25ddc39..fbceab1 100644
> >> --- a/drivers/usb/dwc3/core.c
> >> +++ b/drivers/usb/dwc3/core.c
> >> @@ -838,6 +838,9 @@ static int dwc3_probe(struct platform_device *pdev)
> >> "snps,tx_de_emphasis_quirk");
> >> of_property_read_u8(node, "snps,tx_de_emphasis",
> >> &tx_de_emphasis);
> >> +
> >> + dwc->suspend_on_disconnect_quirk = of_property_read_bool(node,
> >> + "snps,has_suspend_on_disconnect");
> >> } else if (pdata) {
> >> dwc->maximum_speed = pdata->maximum_speed;
> >> dwc->has_lpm_erratum = pdata->has_lpm_erratum;
> >> @@ -864,6 +867,9 @@ static int dwc3_probe(struct platform_device *pdev)
> >> dwc->tx_de_emphasis_quirk = pdata->tx_de_emphasis_quirk;
> >> if (pdata->tx_de_emphasis)
> >> tx_de_emphasis = pdata->tx_de_emphasis;
> >> +
> >> + dwc->suspend_on_disconnect_quirk =
> >> + pdata->has_suspend_on_disconnect;
> >> }
> >>
> >> /* default to superspeed if no maximum_speed passed */
> >> diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> >> index 8090249..d7458ff 100644
> >> --- a/drivers/usb/dwc3/core.h
> >> +++ b/drivers/usb/dwc3/core.h
> >> @@ -832,6 +832,7 @@ struct dwc3 {
> >>
> >> unsigned tx_de_emphasis_quirk:1;
> >> unsigned tx_de_emphasis:2;
> >> + unsigned suspend_on_disconnect_quirk:1;
> >
> > you're missing the comment on the structure and these should be
> > alphabetically sorted.
>
> okay, I see, I'll change it like this:
>
> --- a/drivers/usb/dwc3/core.h
> +++ b/drivers/usb/dwc3/core.h
> @@ -692,6 +692,9 @@ struct dwc3_scratchpad_array {
> * @resize_fifos: tells us it's ok to reconfigure our TxFIFO sizes.
> * @setup_packet_pending: true when there's a Setup Packet in FIFO. Workaround
> * @start_config_issued: true when StartConfig command has been issued
> + * @suspend_on_disconnect_quirk: set if core was configured with
> + * DWC_USB3_SUSPEND_ON_DISCONNECT_EN=1. Note that there's
> + * now way for software to detect this in runtime.
> * @three_stage_setup: set if we perform a three phase setup
> * @disable_scramble_quirk: set if we enable the disable scramble quirk
> * @u2exit_lfps_quirk: set if we enable u2exit lfps quirk
> @@ -818,6 +821,7 @@ struct dwc3 {
> unsigned resize_fifos:1;
> unsigned setup_packet_pending:1;
> unsigned start_config_issued:1;
> + unsigned suspend_on_disconnect_quirk:1;
> unsigned three_stage_setup:1;
>
> unsigned disable_scramble_quirk:1;
>
>
> >
> >> diff --git a/drivers/usb/dwc3/host.c b/drivers/usb/dwc3/host.c
> >> index 12bfd3c..9c42074 100644
> >> --- a/drivers/usb/dwc3/host.c
> >> +++ b/drivers/usb/dwc3/host.c
> >> @@ -53,6 +53,10 @@ int dwc3_host_init(struct dwc3 *dwc)
> >> pdata.usb3_lpm_capable = 1;
> >> #endif
> >>
> >> + if ((dwc->revision < DWC3_REVISION_300A) &&
> >> + dwc->suspend_on_disconnect_quirk)
> >> + pdata.delay_portcsc_clear = 1;
> >> +
> >> ret = platform_device_add_data(xhci, &pdata, sizeof(pdata));
> >> if (ret) {
> >> dev_err(dwc->dev, "couldn't add platform data to xHCI device\n");
> >> diff --git a/drivers/usb/dwc3/platform_data.h b/drivers/usb/dwc3/platform_data.h
> >> index a3a3b6d..69562f1 100644
> >> --- a/drivers/usb/dwc3/platform_data.h
> >> +++ b/drivers/usb/dwc3/platform_data.h
> >> @@ -44,4 +44,5 @@ struct dwc3_platform_data {
> >>
> >> unsigned tx_de_emphasis_quirk:1;
> >> unsigned tx_de_emphasis:2;
> >> + unsigned has_suspend_on_disconnect:1;
> >
> > needs a comment at the top of this structure and should sorted.
>
> okay, I'll do it like this:
>
> --- a/drivers/usb/dwc3/platform_data.h
> +++ b/drivers/usb/dwc3/platform_data.h
> @@ -20,6 +20,13 @@
> #include <linux/usb/ch9.h>
> #include <linux/usb/otg.h>
>
> +/**
> + * struct dwc3_platform_data - platform data of dwc3 controller
> + * @has_suspend_on_disconnect: true if core was configured with
> + * DWC_USB3_SUSPEND_ON_DISCONNECT_EN=1. Note that there's
> + * now way for software to detect this in runtime.
> + */
> +
> struct dwc3_platform_data {
> enum usb_device_speed maximum_speed;
> enum usb_dr_mode dr_mode;
> @@ -32,6 +39,7 @@ struct dwc3_platform_data {
>
> unsigned disable_scramble_quirk:1;
> unsigned has_lpm_erratum:1;
> + unsigned has_suspend_on_disconnect:1;
> unsigned u2exit_lfps_quirk:1;
> unsigned u2ss_inp3_quirk:1;
> unsigned req_p1p2p3_quirk:1;

looks good, thanks

--
balbi

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