Hi Felipe:

Thanks for reviewing these,

2015-01-19 22:50 GMT+08:00 Felipe Balbi [off-list ref]:

Hi,

On Mon, Jan 19, 2015 at 03:56:47PM +0800, Sneeker Yeh wrote:

quoted

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 <redacted>
---
 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;

quoted

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;

Much appreciate,
Sneeker

--
balbi