[v14,2/9] usb: dwc3: core: Access XHCI address space temporarily to read port info

  Currently Multiport DWC3 controllers are host-only capable.
Temporarily map XHCI address space for host-only controllers and parse
XHCI Extended Capabilities registers to read number of usb2 ports and
usb3 ports present on multiport controller. Each USB Port is at least HS
capable.

The port info for usb2 and usb3 phy are identified as num_usb2_ports
and num_usb3_ports. The intention is as follows:

Wherever we need to perform phy operations like:

LOOP_OVER_NUMBER_OF_AVAILABLE_PORTS()
{
	phy_set_mode(dwc->usb2_generic_phy[i], PHY_MODE_USB_HOST);
	phy_set_mode(dwc->usb3_generic_phy[i], PHY_MODE_USB_HOST);
}

If number of usb2 ports is 3, loop can go from index 0-2 for
usb2_generic_phy. If number of usb3-ports is 2, we don't know for sure,
if the first 2 ports are SS capable or some other ports like (2 and 3)
are SS capable. So instead, num_usb2_ports is used to loop around all
phy's (both hs and ss) for performing phy operations. If any
usb3_generic_phy turns out to be NULL, phy operation just bails out.
num_usb3_ports is used to modify GUSB3PIPECTL registers while setting up
phy's as we need to know how many SS capable ports are there for this.

Signed-off-by: Krishna Kurapati <quic_kriskura@quicinc.com>
---
 drivers/usb/dwc3/core.c | 62 +++++++++++++++++++++++++++++++++++++++++
 drivers/usb/dwc3/core.h |  5 ++++
 2 files changed, 67 insertions(+)
  

On Tue, Feb 06, 2024, Krishna Kurapati wrote:
> Currently Multiport DWC3 controllers are host-only capable.
> Temporarily map XHCI address space for host-only controllers and parse
> XHCI Extended Capabilities registers to read number of usb2 ports and
> usb3 ports present on multiport controller. Each USB Port is at least HS
> capable.
> 
> The port info for usb2 and usb3 phy are identified as num_usb2_ports
> and num_usb3_ports. The intention is as follows:
> 
> Wherever we need to perform phy operations like:
> 
> LOOP_OVER_NUMBER_OF_AVAILABLE_PORTS()
> {
> 	phy_set_mode(dwc->usb2_generic_phy[i], PHY_MODE_USB_HOST);
> 	phy_set_mode(dwc->usb3_generic_phy[i], PHY_MODE_USB_HOST);
> }
> 
> If number of usb2 ports is 3, loop can go from index 0-2 for
> usb2_generic_phy. If number of usb3-ports is 2, we don't know for sure,
> if the first 2 ports are SS capable or some other ports like (2 and 3)
> are SS capable. So instead, num_usb2_ports is used to loop around all
> phy's (both hs and ss) for performing phy operations. If any
> usb3_generic_phy turns out to be NULL, phy operation just bails out.
> num_usb3_ports is used to modify GUSB3PIPECTL registers while setting up
> phy's as we need to know how many SS capable ports are there for this.
> 
> Signed-off-by: Krishna Kurapati <quic_kriskura@quicinc.com>
> ---
>  drivers/usb/dwc3/core.c | 62 +++++++++++++++++++++++++++++++++++++++++
>  drivers/usb/dwc3/core.h |  5 ++++
>  2 files changed, 67 insertions(+)
> 
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 3b68e8e45b8b..965eaad195fb 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -39,6 +39,7 @@
>  #include "io.h"
>  
>  #include "debug.h"
> +#include "../host/xhci-ext-caps.h"
>  
>  #define DWC3_DEFAULT_AUTOSUSPEND_DELAY	5000 /* ms */
>  
> @@ -1882,10 +1883,57 @@ static int dwc3_get_clocks(struct dwc3 *dwc)
>  	return 0;
>  }
>  
> +static int dwc3_read_port_info(struct dwc3 *dwc)

I think it may fit better to leave this function definition in host.c.
But you can also argue to leave it here. Let me know what you think.

> +{
> +	void __iomem *base;
> +	u8 major_revision;
> +	u32 offset;
> +	u32 val;
> +
> +	/*
> +	 * Remap xHCI address space to access XHCI ext cap regs since it is
> +	 * needed to get information on number of ports present.
> +	 */
> +	base = ioremap(dwc->xhci_resources[0].start,
> +		       resource_size(&dwc->xhci_resources[0]));
> +	if (IS_ERR(base))

ioremap returns NULL on errors.

> +		return PTR_ERR(base);
> +
> +	offset = 0;
> +	do {
> +		offset = xhci_find_next_ext_cap(base, offset,
> +						XHCI_EXT_CAPS_PROTOCOL);
> +		if (!offset)
> +			break;
> +
> +		val = readl(base + offset);
> +		major_revision = XHCI_EXT_PORT_MAJOR(val);
> +
> +		val = readl(base + offset + 0x08);
> +		if (major_revision == 0x03) {
> +			dwc->num_usb3_ports += XHCI_EXT_PORT_COUNT(val);
> +		} else if (major_revision <= 0x02) {
> +			dwc->num_usb2_ports += XHCI_EXT_PORT_COUNT(val);
> +		} else {
> +			dev_warn(dwc->dev,
> +				 "unrecognized port major revision %d\n",
> +							major_revision);
> +		}
> +	} while (1);
> +
> +	dev_dbg(dwc->dev, "hs-ports: %u ss-ports: %u\n",
> +		dwc->num_usb2_ports, dwc->num_usb3_ports);
> +
> +	iounmap(base);
> +
> +	return 0;
> +}
> +

>  static int dwc3_probe(struct platform_device *pdev)
>  {
>  	struct device		*dev = &pdev->dev;
>  	struct resource		*res, dwc_res;
> +	unsigned int		hw_mode;
>  	void __iomem		*regs;
>  	struct dwc3		*dwc;
>  	int			ret;
> @@ -1969,6 +2017,20 @@ static int dwc3_probe(struct platform_device *pdev)
>  			goto err_disable_clks;
>  	}
>  
> +	/*
> +	 * Currently only DWC3 controllers that are host-only capable
> +	 * support Multiport.
> +	 */
> +	hw_mode = DWC3_GHWPARAMS0_MODE(dwc->hwparams.hwparams0);
> +	if (hw_mode == DWC3_GHWPARAMS0_MODE_HOST) {
> +		ret = dwc3_read_port_info(dwc);

The function name here can be reworded as it does more than reading the
port info. Perhaps dwc3_get_num_ports()?

> +		if (ret)
> +			goto err_disable_clks;
> +	} else {
> +		dwc->num_usb2_ports = 1;
> +		dwc->num_usb3_ports = 1;
> +	}
> +
>  	spin_lock_init(&dwc->lock);
>  	mutex_init(&dwc->mutex);
>  
> diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> index df544ec730d2..4c52fef99838 100644
> --- a/drivers/usb/dwc3/core.h
> +++ b/drivers/usb/dwc3/core.h
> @@ -1039,6 +1039,8 @@ struct dwc3_scratchpad_array {
>   * @usb3_phy: pointer to USB3 PHY
>   * @usb2_generic_phy: pointer to USB2 PHY
>   * @usb3_generic_phy: pointer to USB3 PHY
> + * @num_usb2_ports: number of USB2 ports
> + * @num_usb3_ports: number of USB3 ports
>   * @phys_ready: flag to indicate that PHYs are ready
>   * @ulpi: pointer to ulpi interface
>   * @ulpi_ready: flag to indicate that ULPI is initialized
> @@ -1187,6 +1189,9 @@ struct dwc3 {
>  	struct phy		*usb2_generic_phy;
>  	struct phy		*usb3_generic_phy;
>  
> +	u8			num_usb2_ports;
> +	u8			num_usb3_ports;
> +
>  	bool			phys_ready;
>  
>  	struct ulpi		*ulpi;
> -- 
> 2.34.1
> 

Thanks,
Thinh
  

On 2/9/2024 5:12 AM, Thinh Nguyen wrote:
> On Tue, Feb 06, 2024, Krishna Kurapati wrote:
>> Currently Multiport DWC3 controllers are host-only capable.
>> Temporarily map XHCI address space for host-only controllers and parse
>> XHCI Extended Capabilities registers to read number of usb2 ports and
>> usb3 ports present on multiport controller. Each USB Port is at least HS
>> capable.
>>
>> The port info for usb2 and usb3 phy are identified as num_usb2_ports
>> and num_usb3_ports. The intention is as follows:
>>
>> Wherever we need to perform phy operations like:
>>
>> LOOP_OVER_NUMBER_OF_AVAILABLE_PORTS()
>> {
>> 	phy_set_mode(dwc->usb2_generic_phy[i], PHY_MODE_USB_HOST);
>> 	phy_set_mode(dwc->usb3_generic_phy[i], PHY_MODE_USB_HOST);
>> }
>>
>> If number of usb2 ports is 3, loop can go from index 0-2 for
>> usb2_generic_phy. If number of usb3-ports is 2, we don't know for sure,
>> if the first 2 ports are SS capable or some other ports like (2 and 3)
>> are SS capable. So instead, num_usb2_ports is used to loop around all
>> phy's (both hs and ss) for performing phy operations. If any
>> usb3_generic_phy turns out to be NULL, phy operation just bails out.
>> num_usb3_ports is used to modify GUSB3PIPECTL registers while setting up
>> phy's as we need to know how many SS capable ports are there for this.
>>
>> Signed-off-by: Krishna Kurapati <quic_kriskura@quicinc.com>
>> ---
>>   drivers/usb/dwc3/core.c | 62 +++++++++++++++++++++++++++++++++++++++++
>>   drivers/usb/dwc3/core.h |  5 ++++
>>   2 files changed, 67 insertions(+)
>>
>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
>> index 3b68e8e45b8b..965eaad195fb 100644
>> --- a/drivers/usb/dwc3/core.c
>> +++ b/drivers/usb/dwc3/core.c
>> @@ -39,6 +39,7 @@
>>   #include "io.h"
>>   
>>   #include "debug.h"
>> +#include "../host/xhci-ext-caps.h"
>>   
>>   #define DWC3_DEFAULT_AUTOSUSPEND_DELAY	5000 /* ms */
>>   
>> @@ -1882,10 +1883,57 @@ static int dwc3_get_clocks(struct dwc3 *dwc)
>>   	return 0;
>>   }
>>   
>> +static int dwc3_read_port_info(struct dwc3 *dwc)
> 
> I think it may fit better to leave this function definition in host.c.
> But you can also argue to leave it here. Let me know what you think.

I'd like to keep it here for now.

> 
>> +{
>> +	void __iomem *base;
>> +	u8 major_revision;
>> +	u32 offset;
>> +	u32 val;
>> +
>> +	/*
>> +	 * Remap xHCI address space to access XHCI ext cap regs since it is
>> +	 * needed to get information on number of ports present.
>> +	 */
>> +	base = ioremap(dwc->xhci_resources[0].start,
>> +		       resource_size(&dwc->xhci_resources[0]));
>> +	if (IS_ERR(base))
> 
> ioremap returns NULL on errors.
> 

Can we keep the above for now if the v14 series goes well. I'll post a 
patch later for this. Incase it turns out I need v15 I will make this 
change in v15.

>> +		return PTR_ERR(base);
>> +
>> +	offset = 0;
>> +	do {
>> +		offset = xhci_find_next_ext_cap(base, offset,
>> +						XHCI_EXT_CAPS_PROTOCOL);
>> +		if (!offset)
>> +			break;
>> +
>> +		val = readl(base + offset);
>> +		major_revision = XHCI_EXT_PORT_MAJOR(val);
>> +
>> +		val = readl(base + offset + 0x08);
>> +		if (major_revision == 0x03) {
>> +			dwc->num_usb3_ports += XHCI_EXT_PORT_COUNT(val);
>> +		} else if (major_revision <= 0x02) {
>> +			dwc->num_usb2_ports += XHCI_EXT_PORT_COUNT(val);
>> +		} else {
>> +			dev_warn(dwc->dev,
>> +				 "unrecognized port major revision %d\n",
>> +							major_revision);
>> +		}
>> +	} while (1);
>> +
>> +	dev_dbg(dwc->dev, "hs-ports: %u ss-ports: %u\n",
>> +		dwc->num_usb2_ports, dwc->num_usb3_ports);
>> +
>> +	iounmap(base);
>> +
>> +	return 0;
>> +}
>> +
> 
>>   static int dwc3_probe(struct platform_device *pdev)
>>   {
>>   	struct device		*dev = &pdev->dev;
>>   	struct resource		*res, dwc_res;
>> +	unsigned int		hw_mode;
>>   	void __iomem		*regs;
>>   	struct dwc3		*dwc;
>>   	int			ret;
>> @@ -1969,6 +2017,20 @@ static int dwc3_probe(struct platform_device *pdev)
>>   			goto err_disable_clks;
>>   	}
>>   
>> +	/*
>> +	 * Currently only DWC3 controllers that are host-only capable
>> +	 * support Multiport.
>> +	 */
>> +	hw_mode = DWC3_GHWPARAMS0_MODE(dwc->hwparams.hwparams0);
>> +	if (hw_mode == DWC3_GHWPARAMS0_MODE_HOST) {
>> +		ret = dwc3_read_port_info(dwc);
> 
> The function name here can be reworded as it does more than reading the
> port info. Perhaps dwc3_get_num_ports()?
> 
I am fine either ways. I'll change the func name in v15.

Regards,
Krishna,
  

On Tue, Feb 06, 2024 at 10:48:18AM +0530, Krishna Kurapati wrote:
> Currently Multiport DWC3 controllers are host-only capable.
> Temporarily map XHCI address space for host-only controllers and parse
> XHCI Extended Capabilities registers to read number of usb2 ports and
> usb3 ports present on multiport controller. Each USB Port is at least HS
> capable.
> 
> The port info for usb2 and usb3 phy are identified as num_usb2_ports
> and num_usb3_ports. The intention is as follows:
> 
> Wherever we need to perform phy operations like:
> 
> LOOP_OVER_NUMBER_OF_AVAILABLE_PORTS()
> {
> 	phy_set_mode(dwc->usb2_generic_phy[i], PHY_MODE_USB_HOST);
> 	phy_set_mode(dwc->usb3_generic_phy[i], PHY_MODE_USB_HOST);
> }
> 
> If number of usb2 ports is 3, loop can go from index 0-2 for
> usb2_generic_phy. If number of usb3-ports is 2, we don't know for sure,
> if the first 2 ports are SS capable or some other ports like (2 and 3)
> are SS capable. So instead, num_usb2_ports is used to loop around all
> phy's (both hs and ss) for performing phy operations. If any
> usb3_generic_phy turns out to be NULL, phy operation just bails out.
> num_usb3_ports is used to modify GUSB3PIPECTL registers while setting up
> phy's as we need to know how many SS capable ports are there for this.
> 
> Signed-off-by: Krishna Kurapati <quic_kriskura@quicinc.com>

Reviewed-by: Bjorn Andersson <andersson@kernel.org>

Regards,
Bjorn

> ---
>  drivers/usb/dwc3/core.c | 62 +++++++++++++++++++++++++++++++++++++++++
>  drivers/usb/dwc3/core.h |  5 ++++
>  2 files changed, 67 insertions(+)
> 
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 3b68e8e45b8b..965eaad195fb 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -39,6 +39,7 @@
>  #include "io.h"
>  
>  #include "debug.h"
> +#include "../host/xhci-ext-caps.h"
>  
>  #define DWC3_DEFAULT_AUTOSUSPEND_DELAY	5000 /* ms */
>  
> @@ -1882,10 +1883,57 @@ static int dwc3_get_clocks(struct dwc3 *dwc)
>  	return 0;
>  }
>  
> +static int dwc3_read_port_info(struct dwc3 *dwc)
> +{
> +	void __iomem *base;
> +	u8 major_revision;
> +	u32 offset;
> +	u32 val;
> +
> +	/*
> +	 * Remap xHCI address space to access XHCI ext cap regs since it is
> +	 * needed to get information on number of ports present.
> +	 */
> +	base = ioremap(dwc->xhci_resources[0].start,
> +		       resource_size(&dwc->xhci_resources[0]));
> +	if (IS_ERR(base))
> +		return PTR_ERR(base);
> +
> +	offset = 0;
> +	do {
> +		offset = xhci_find_next_ext_cap(base, offset,
> +						XHCI_EXT_CAPS_PROTOCOL);
> +		if (!offset)
> +			break;
> +
> +		val = readl(base + offset);
> +		major_revision = XHCI_EXT_PORT_MAJOR(val);
> +
> +		val = readl(base + offset + 0x08);
> +		if (major_revision == 0x03) {
> +			dwc->num_usb3_ports += XHCI_EXT_PORT_COUNT(val);
> +		} else if (major_revision <= 0x02) {
> +			dwc->num_usb2_ports += XHCI_EXT_PORT_COUNT(val);
> +		} else {
> +			dev_warn(dwc->dev,
> +				 "unrecognized port major revision %d\n",
> +							major_revision);
> +		}
> +	} while (1);
> +
> +	dev_dbg(dwc->dev, "hs-ports: %u ss-ports: %u\n",
> +		dwc->num_usb2_ports, dwc->num_usb3_ports);
> +
> +	iounmap(base);
> +
> +	return 0;
> +}
> +
>  static int dwc3_probe(struct platform_device *pdev)
>  {
>  	struct device		*dev = &pdev->dev;
>  	struct resource		*res, dwc_res;
> +	unsigned int		hw_mode;
>  	void __iomem		*regs;
>  	struct dwc3		*dwc;
>  	int			ret;
> @@ -1969,6 +2017,20 @@ static int dwc3_probe(struct platform_device *pdev)
>  			goto err_disable_clks;
>  	}
>  
> +	/*
> +	 * Currently only DWC3 controllers that are host-only capable
> +	 * support Multiport.
> +	 */
> +	hw_mode = DWC3_GHWPARAMS0_MODE(dwc->hwparams.hwparams0);
> +	if (hw_mode == DWC3_GHWPARAMS0_MODE_HOST) {
> +		ret = dwc3_read_port_info(dwc);
> +		if (ret)
> +			goto err_disable_clks;
> +	} else {
> +		dwc->num_usb2_ports = 1;
> +		dwc->num_usb3_ports = 1;
> +	}
> +
>  	spin_lock_init(&dwc->lock);
>  	mutex_init(&dwc->mutex);
>  
> diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> index df544ec730d2..4c52fef99838 100644
> --- a/drivers/usb/dwc3/core.h
> +++ b/drivers/usb/dwc3/core.h
> @@ -1039,6 +1039,8 @@ struct dwc3_scratchpad_array {
>   * @usb3_phy: pointer to USB3 PHY
>   * @usb2_generic_phy: pointer to USB2 PHY
>   * @usb3_generic_phy: pointer to USB3 PHY
> + * @num_usb2_ports: number of USB2 ports
> + * @num_usb3_ports: number of USB3 ports
>   * @phys_ready: flag to indicate that PHYs are ready
>   * @ulpi: pointer to ulpi interface
>   * @ulpi_ready: flag to indicate that ULPI is initialized
> @@ -1187,6 +1189,9 @@ struct dwc3 {
>  	struct phy		*usb2_generic_phy;
>  	struct phy		*usb3_generic_phy;
>  
> +	u8			num_usb2_ports;
> +	u8			num_usb3_ports;
> +
>  	bool			phys_ready;
>  
>  	struct ulpi		*ulpi;
> -- 
> 2.34.1
>
  

On Fri, Feb 09, 2024, Krishna Kurapati PSSNV wrote:
> 
> 
> On 2/9/2024 5:12 AM, Thinh Nguyen wrote:
> > On Tue, Feb 06, 2024, Krishna Kurapati wrote:
> > > Currently Multiport DWC3 controllers are host-only capable.
> > > Temporarily map XHCI address space for host-only controllers and parse
> > > XHCI Extended Capabilities registers to read number of usb2 ports and
> > > usb3 ports present on multiport controller. Each USB Port is at least HS
> > > capable.
> > > 
> > > The port info for usb2 and usb3 phy are identified as num_usb2_ports
> > > and num_usb3_ports. The intention is as follows:
> > > 
> > > Wherever we need to perform phy operations like:
> > > 
> > > LOOP_OVER_NUMBER_OF_AVAILABLE_PORTS()
> > > {
> > > 	phy_set_mode(dwc->usb2_generic_phy[i], PHY_MODE_USB_HOST);
> > > 	phy_set_mode(dwc->usb3_generic_phy[i], PHY_MODE_USB_HOST);
> > > }
> > > 
> > > If number of usb2 ports is 3, loop can go from index 0-2 for
> > > usb2_generic_phy. If number of usb3-ports is 2, we don't know for sure,
> > > if the first 2 ports are SS capable or some other ports like (2 and 3)
> > > are SS capable. So instead, num_usb2_ports is used to loop around all
> > > phy's (both hs and ss) for performing phy operations. If any
> > > usb3_generic_phy turns out to be NULL, phy operation just bails out.
> > > num_usb3_ports is used to modify GUSB3PIPECTL registers while setting up
> > > phy's as we need to know how many SS capable ports are there for this.
> > > 
> > > Signed-off-by: Krishna Kurapati <quic_kriskura@quicinc.com>
> > > ---
> > >   drivers/usb/dwc3/core.c | 62 +++++++++++++++++++++++++++++++++++++++++
> > >   drivers/usb/dwc3/core.h |  5 ++++
> > >   2 files changed, 67 insertions(+)
> > > 
> > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> > > index 3b68e8e45b8b..965eaad195fb 100644
> > > --- a/drivers/usb/dwc3/core.c
> > > +++ b/drivers/usb/dwc3/core.c
> > > @@ -39,6 +39,7 @@
> > >   #include "io.h"
> > >   #include "debug.h"
> > > +#include "../host/xhci-ext-caps.h"
> > >   #define DWC3_DEFAULT_AUTOSUSPEND_DELAY	5000 /* ms */
> > > @@ -1882,10 +1883,57 @@ static int dwc3_get_clocks(struct dwc3 *dwc)
> > >   	return 0;
> > >   }
> > > +static int dwc3_read_port_info(struct dwc3 *dwc)
> > 
> > I think it may fit better to leave this function definition in host.c.
> > But you can also argue to leave it here. Let me know what you think.
> 
> I'd like to keep it here for now.
> 
> > 
> > > +{
> > > +	void __iomem *base;
> > > +	u8 major_revision;
> > > +	u32 offset;
> > > +	u32 val;
> > > +
> > > +	/*
> > > +	 * Remap xHCI address space to access XHCI ext cap regs since it is
> > > +	 * needed to get information on number of ports present.
> > > +	 */
> > > +	base = ioremap(dwc->xhci_resources[0].start,
> > > +		       resource_size(&dwc->xhci_resources[0]));
> > > +	if (IS_ERR(base))
> > 
> > ioremap returns NULL on errors.
> > 
> 
> Can we keep the above for now if the v14 series goes well. I'll post a patch
> later for this. Incase it turns out I need v15 I will make this change in
> v15.

Sure. It's a minor issue and shouldn't hold back this series.

> 
> > > +		return PTR_ERR(base);
> > > +
> > > +	offset = 0;
> > > +	do {
> > > +		offset = xhci_find_next_ext_cap(base, offset,
> > > +						XHCI_EXT_CAPS_PROTOCOL);
> > > +		if (!offset)
> > > +			break;
> > > +
> > > +		val = readl(base + offset);
> > > +		major_revision = XHCI_EXT_PORT_MAJOR(val);
> > > +
> > > +		val = readl(base + offset + 0x08);
> > > +		if (major_revision == 0x03) {
> > > +			dwc->num_usb3_ports += XHCI_EXT_PORT_COUNT(val);
> > > +		} else if (major_revision <= 0x02) {
> > > +			dwc->num_usb2_ports += XHCI_EXT_PORT_COUNT(val);
> > > +		} else {
> > > +			dev_warn(dwc->dev,
> > > +				 "unrecognized port major revision %d\n",
> > > +							major_revision);
> > > +		}
> > > +	} while (1);
> > > +
> > > +	dev_dbg(dwc->dev, "hs-ports: %u ss-ports: %u\n",
> > > +		dwc->num_usb2_ports, dwc->num_usb3_ports);
> > > +
> > > +	iounmap(base);
> > > +
> > > +	return 0;
> > > +}
> > > +
> > 
> > >   static int dwc3_probe(struct platform_device *pdev)
> > >   {
> > >   	struct device		*dev = &pdev->dev;
> > >   	struct resource		*res, dwc_res;
> > > +	unsigned int		hw_mode;
> > >   	void __iomem		*regs;
> > >   	struct dwc3		*dwc;
> > >   	int			ret;
> > > @@ -1969,6 +2017,20 @@ static int dwc3_probe(struct platform_device *pdev)
> > >   			goto err_disable_clks;
> > >   	}
> > > +	/*
> > > +	 * Currently only DWC3 controllers that are host-only capable
> > > +	 * support Multiport.
> > > +	 */
> > > +	hw_mode = DWC3_GHWPARAMS0_MODE(dwc->hwparams.hwparams0);
> > > +	if (hw_mode == DWC3_GHWPARAMS0_MODE_HOST) {
> > > +		ret = dwc3_read_port_info(dwc);
> > 
> > The function name here can be reworded as it does more than reading the
> > port info. Perhaps dwc3_get_num_ports()?
> > 
> I am fine either ways. I'll change the func name in v15.
> 

Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>

Thanks,
Thinh