[PATCH 0/5] usb: cdns3: misc improvements

[PATCH 0/5] usb: cdns3: misc improvements

[Peter Chen]

Peter Chen (5):
  usb: cdns3: core: quit if it uses role switch class
  usb: cdns3: gadget: set fast access bit
  usb: cdns3: gadget: clear the interrupt status when disconnect the
    host
  usb: cdns3: drd: call PHY .set_mode accordingly
  usb: cdns3: gadget: move wait configuration operation

 drivers/usb/cdns3/core.c   |  4 ++++
 drivers/usb/cdns3/drd.c    |  5 +++++
 drivers/usb/cdns3/ep0.c    | 10 +++++++++-
 drivers/usb/cdns3/gadget.c | 15 ++++++++-------
 4 files changed, 26 insertions(+), 8 deletions(-)

-- 
2.17.1

[PATCH 1/5] usb: cdns3: core: quit if it uses role switch class

[Peter Chen]

If the board uses role switch class for switching the role, it should
not depends on SoC OTG hardware siginal any more, so quit early.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/usb/cdns3/core.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c
index faee5ec5fc20..96c2da4e20c5 100644
--- a/drivers/usb/cdns3/core.c
+++ b/drivers/usb/cdns3/core.c
@@ -280,6 +280,10 @@ int cdns3_hw_role_switch(struct cdns3 *cdns)
 	enum usb_role real_role, current_role;
 	int ret = 0;
 
+	/* Depends on role switch class */
+	if (cdns->role_sw)
+		return 0;
+
 	pm_runtime_get_sync(cdns->dev);
 
 	current_role = cdns->role;
-- 
2.17.1

Re: [PATCH 1/5] usb: cdns3: core: quit if it uses role switch class

[Roger Quadros]

Peter/Felipe,

On 01/09/2020 05:33, Peter Chen wrote:
> If the board uses role switch class for switching the role, it should
> not depends on SoC OTG hardware siginal any more, so quit early.
> 
> Signed-off-by: Peter Chen <peter.chen@nxp.com>
> ---
>   drivers/usb/cdns3/core.c | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c
> index faee5ec5fc20..96c2da4e20c5 100644
> --- a/drivers/usb/cdns3/core.c
> +++ b/drivers/usb/cdns3/core.c
> @@ -280,6 +280,10 @@ int cdns3_hw_role_switch(struct cdns3 *cdns)
>   	enum usb_role real_role, current_role;
>   	int ret = 0;
>   
> +	/* Depends on role switch class */
> +	if (cdns->role_sw)
> +		return 0;
> +

This breaks h/w based role switching for us.

cdsn->role_sw would always be non zero, right, which means h/w based role swithching
will be bypassed for all platforms.

>   	pm_runtime_get_sync(cdns->dev);
>   
>   	current_role = cdns->role;
> 

cheers,
-roger
-- 
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

[PATCH 2/5] usb: cdns3: gadget: set fast access bit

[Peter Chen]

Below is the recommendation from Cadence designer:
	Using this bit to be sure that PHY clock is keeping up in active
	state. It's good to keep Fast Access bit enabled as long as there
	is any access to USB register.

It is used to fix the potential ARM core hang when visit controller
register after DEVDS (.pullup is cleared) is set, the threaded irq
may be scheduled at that time.

Cc: Pawel Laszczak <pawell@cadence.com>
Reviewed-by: Jun Li <jun.li@nxp.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/usb/cdns3/gadget.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/usb/cdns3/gadget.c b/drivers/usb/cdns3/gadget.c
index 2551901e8470..03b54c239944 100644
--- a/drivers/usb/cdns3/gadget.c
+++ b/drivers/usb/cdns3/gadget.c
@@ -2783,6 +2783,8 @@ static void cdns3_gadget_config(struct cdns3_device *priv_dev)
 	/* enable generic interrupt*/
 	writel(USB_IEN_INIT, &regs->usb_ien);
 	writel(USB_CONF_CLK2OFFDS | USB_CONF_L1DS, &regs->usb_conf);
+	/*  keep Fast Access bit */
+	writel(PUSB_PWR_FST_REG_ACCESS, &priv_dev->regs->usb_pwr);
 
 	cdns3_configure_dmult(priv_dev, NULL);
 }
@@ -2866,6 +2868,7 @@ static int cdns3_gadget_udc_stop(struct usb_gadget *gadget)
 
 	/* disable interrupt for device */
 	writel(0, &priv_dev->regs->usb_ien);
+	writel(0, &priv_dev->regs->usb_pwr);
 	writel(USB_CONF_DEVDS, &priv_dev->regs->usb_conf);
 
 	return 0;
-- 
2.17.1

[PATCH 3/5] usb: cdns3: gadget: clear the interrupt status when disconnect the host

[Peter Chen]

It is meaningless to handle any interrupts after disconnecting
with host

Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/usb/cdns3/gadget.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/cdns3/gadget.c b/drivers/usb/cdns3/gadget.c
index 03b54c239944..829bc917df39 100644
--- a/drivers/usb/cdns3/gadget.c
+++ b/drivers/usb/cdns3/gadget.c
@@ -2739,10 +2739,13 @@ static int cdns3_gadget_pullup(struct usb_gadget *gadget, int is_on)
 {
 	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
 
-	if (is_on)
+	if (is_on) {
 		writel(USB_CONF_DEVEN, &priv_dev->regs->usb_conf);
-	else
+	} else {
+		writel(~0, &priv_dev->regs->ep_ists);
+		writel(~0, &priv_dev->regs->usb_ists);
 		writel(USB_CONF_DEVDS, &priv_dev->regs->usb_conf);
+	}
 
 	return 0;
 }
-- 
2.17.1

[PATCH 4/5] usb: cdns3: drd: call PHY .set_mode accordingly

[Peter Chen]

Some PHYs may need to enter related mode, and do some settings.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/usb/cdns3/drd.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/usb/cdns3/drd.c b/drivers/usb/cdns3/drd.c
index 5f2685cadf5e..31fddf84f226 100644
--- a/drivers/usb/cdns3/drd.c
+++ b/drivers/usb/cdns3/drd.c
@@ -15,6 +15,7 @@
 #include <linux/delay.h>
 #include <linux/iopoll.h>
 #include <linux/usb/otg.h>
+#include <linux/phy/phy.h>
 
 #include "gadget.h"
 #include "drd.h"
@@ -145,6 +146,7 @@ int cdns3_drd_host_on(struct cdns3 *cdns)
 	if (ret)
 		dev_err(cdns->dev, "timeout waiting for xhci_ready\n");
 
+	phy_set_mode(cdns->usb3_phy, PHY_MODE_USB_HOST);
 	return ret;
 }
 
@@ -164,6 +166,7 @@ void cdns3_drd_host_off(struct cdns3 *cdns)
 	readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
 				  !(val & OTGSTATE_HOST_STATE_MASK),
 				  1, 2000000);
+	phy_set_mode(cdns->usb3_phy, PHY_MODE_INVALID);
 }
 
 /**
@@ -190,6 +193,7 @@ int cdns3_drd_gadget_on(struct cdns3 *cdns)
 		return ret;
 	}
 
+	phy_set_mode(cdns->usb3_phy, PHY_MODE_USB_DEVICE);
 	return 0;
 }
 
@@ -213,6 +217,7 @@ void cdns3_drd_gadget_off(struct cdns3 *cdns)
 	readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
 				  !(val & OTGSTATE_DEV_STATE_MASK),
 				  1, 2000000);
+	phy_set_mode(cdns->usb3_phy, PHY_MODE_INVALID);
 }
 
 /**
-- 
2.17.1

[PATCH 5/5] usb: cdns3: gadget: move wait configuration operation

[Peter Chen]

After commit f4cfe5ce607d ("usb: cdns3: gadget: improve the
set_configuration handling"), the software will inform the
hardware the request has finished at cdns3_ep0_complete_setup.
The configuration set bit is only set after request has finished,
so it needs to move waiting operation after that. Meanwhile,
if it is timeout, it will show warning message and return error.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/usb/cdns3/ep0.c    | 10 +++++++++-
 drivers/usb/cdns3/gadget.c |  5 -----
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/cdns3/ep0.c b/drivers/usb/cdns3/ep0.c
index d9779abc65b2..4761c852d9c4 100644
--- a/drivers/usb/cdns3/ep0.c
+++ b/drivers/usb/cdns3/ep0.c
@@ -717,9 +717,17 @@ static int cdns3_gadget_ep0_queue(struct usb_ep *ep,
 
 	/* send STATUS stage. Should be called only for SET_CONFIGURATION */
 	if (priv_dev->ep0_stage == CDNS3_STATUS_STAGE) {
+		u32 val;
+
 		cdns3_select_ep(priv_dev, 0x00);
 		cdns3_set_hw_configuration(priv_dev);
 		cdns3_ep0_complete_setup(priv_dev, 0, 1);
+		/* wait until configuration set */
+		ret = readl_poll_timeout_atomic(&priv_dev->regs->usb_sts, val,
+					  val & USB_STS_CFGSTS_MASK, 1, 100);
+		if (ret == -ETIMEDOUT)
+			dev_warn(priv_dev->dev, "timeout for waiting configuration set\n");
+
 		request->actual = 0;
 		priv_dev->status_completion_no_call = true;
 		priv_dev->pending_status_request = request;
@@ -731,7 +739,7 @@ static int cdns3_gadget_ep0_queue(struct usb_ep *ep,
 		 * ep0_queue is back.
 		 */
 		queue_work(system_freezable_wq, &priv_dev->pending_status_wq);
-		return 0;
+		return ret;
 	}
 
 	if (!list_empty(&priv_ep->pending_req_list)) {
diff --git a/drivers/usb/cdns3/gadget.c b/drivers/usb/cdns3/gadget.c
index 829bc917df39..2ea4d30e1828 100644
--- a/drivers/usb/cdns3/gadget.c
+++ b/drivers/usb/cdns3/gadget.c
@@ -1309,7 +1309,6 @@ void cdns3_set_hw_configuration(struct cdns3_device *priv_dev)
 {
 	struct cdns3_endpoint *priv_ep;
 	struct usb_ep *ep;
-	int val;
 
 	if (priv_dev->hw_configured_flag)
 		return;
@@ -1319,10 +1318,6 @@ void cdns3_set_hw_configuration(struct cdns3_device *priv_dev)
 	cdns3_set_register_bit(&priv_dev->regs->usb_conf,
 			       USB_CONF_U1EN | USB_CONF_U2EN);
 
-	/* wait until configuration set */
-	readl_poll_timeout_atomic(&priv_dev->regs->usb_sts, val,
-				  val & USB_STS_CFGSTS_MASK, 1, 100);
-
 	priv_dev->hw_configured_flag = 1;
 
 	list_for_each_entry(ep, &priv_dev->gadget.ep_list, ep_list) {
-- 
2.17.1

Re: [PATCH 0/5] usb: cdns3: misc improvements

[Peter Chen]

On Tue, Sep 1, 2020 at 10:36 AM Peter Chen <peter.chen@nxp.com> wrote:
>
> Peter Chen (5):
>   usb: cdns3: core: quit if it uses role switch class
>   usb: cdns3: gadget: set fast access bit
>   usb: cdns3: gadget: clear the interrupt status when disconnect the
>     host
>   usb: cdns3: drd: call PHY .set_mode accordingly
>   usb: cdns3: gadget: move wait configuration operation
>
>  drivers/usb/cdns3/core.c   |  4 ++++
>  drivers/usb/cdns3/drd.c    |  5 +++++
>  drivers/usb/cdns3/ep0.c    | 10 +++++++++-
>  drivers/usb/cdns3/gadget.c | 15 ++++++++-------
>  4 files changed, 26 insertions(+), 8 deletions(-)
>
> --

A gentle ping.

Peter