2018-12-09 19:02:45

by Martin Blumenstingl

[permalink] [raw]
Subject: [PATCH 0/1] usb: dwc2: fix hot plugging on Amlogic devices

This is a follow-up to an issue I had a while ago but never had the
time to debug it: [0]
Short summary:
- on Meson8b USB devices are only detected if they are plugged in
before booting Linux
- if they are plugged in after booting Linux they are not detected
(except when running "lsusb -v" as a workaround)

Christian Hewitt made me aware of a similar issue that was fixed for
Rockchip devices. This single patch applies the same fix to the
Amlogic devices as well.


[0] http://lists.infradead.org/pipermail/linux-amlogic/2018-May/007310.html


Martin Blumenstingl (1):
usb: dwc2: disable power_down on Amlogic devices

drivers/usb/dwc2/params.c | 1 +
1 file changed, 1 insertion(+)

--
2.19.2



2018-12-09 19:04:08

by Martin Blumenstingl

[permalink] [raw]
Subject: [PATCH 1/1] usb: dwc2: disable power_down on Amlogic devices

Disable power_down by setting the parameter to
DWC2_POWER_DOWN_PARAM_NONE. This fixes a problem on various Amlogic
Meson SoCs where USB devices are only recognized when plugged in before
booting Linux. A hot-plugged USB device was not detected even though the
device got power (my USB thumb drive for example has an LED which lit
up).

A similar fix was implemented for Rockchip SoCs in commit c216765d3a1def
("usb: dwc2: disable power_down on rockchip devices"). That commit
suggests that a change in the dwc2 driver is the cause because the
default value for the "hibernate" parameter (which then got renamed to
"power_down" to support other modes) was changed in the v4.17 merge
window with:
commit 6d23ee9caa6790 ("Merge tag 'usb-for-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-testing").

Cc: <[email protected]> # 4.19
Suggested-by: Christian Hewitt <[email protected]>
Signed-off-by: Martin Blumenstingl <[email protected]>
---
drivers/usb/dwc2/params.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/usb/dwc2/params.c b/drivers/usb/dwc2/params.c
index 7c1b6938f212..38c813b1d203 100644
--- a/drivers/usb/dwc2/params.c
+++ b/drivers/usb/dwc2/params.c
@@ -111,6 +111,7 @@ static void dwc2_set_amlogic_params(struct dwc2_hsotg *hsotg)
p->phy_type = DWC2_PHY_TYPE_PARAM_UTMI;
p->ahbcfg = GAHBCFG_HBSTLEN_INCR8 <<
GAHBCFG_HBSTLEN_SHIFT;
+ p->power_down = DWC2_POWER_DOWN_PARAM_NONE;
}

static void dwc2_set_amcc_params(struct dwc2_hsotg *hsotg)
--
2.19.2


2018-12-10 06:05:23

by Minas Harutyunyan

[permalink] [raw]
Subject: Re: [PATCH 1/1] usb: dwc2: disable power_down on Amlogic devices

On 12/9/2018 11:01 PM, Martin Blumenstingl wrote:
> Disable power_down by setting the parameter to
> DWC2_POWER_DOWN_PARAM_NONE. This fixes a problem on various Amlogic
> Meson SoCs where USB devices are only recognized when plugged in before
> booting Linux. A hot-plugged USB device was not detected even though the
> device got power (my USB thumb drive for example has an LED which lit
> up).
>
> A similar fix was implemented for Rockchip SoCs in commit c216765d3a1def
> ("usb: dwc2: disable power_down on rockchip devices"). That commit
> suggests that a change in the dwc2 driver is the cause because the
> default value for the "hibernate" parameter (which then got renamed to
> "power_down" to support other modes) was changed in the v4.17 merge
> window with:
> commit 6d23ee9caa6790 ("Merge tag 'usb-for-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-testing").
>
> Cc: <[email protected]> # 4.19
> Suggested-by: Christian Hewitt <[email protected]>
> Signed-off-by: Martin Blumenstingl <[email protected]>

Acked-by: Minas Harutyunyan <[email protected]>
> ---
> drivers/usb/dwc2/params.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/usb/dwc2/params.c b/drivers/usb/dwc2/params.c
> index 7c1b6938f212..38c813b1d203 100644
> --- a/drivers/usb/dwc2/params.c
> +++ b/drivers/usb/dwc2/params.c
> @@ -111,6 +111,7 @@ static void dwc2_set_amlogic_params(struct dwc2_hsotg *hsotg)
> p->phy_type = DWC2_PHY_TYPE_PARAM_UTMI;
> p->ahbcfg = GAHBCFG_HBSTLEN_INCR8 <<
> GAHBCFG_HBSTLEN_SHIFT;
> + p->power_down = DWC2_POWER_DOWN_PARAM_NONE;
> }
>
> static void dwc2_set_amcc_params(struct dwc2_hsotg *hsotg)
>


2018-12-10 14:35:58

by Brad Harper

[permalink] [raw]
Subject: Re: [PATCH 1/1] usb: dwc2: disable power_down on Amlogic devices

On 10/12/2018 6:01 am, Martin Blumenstingl wrote:
> Disable power_down by setting the parameter to
> DWC2_POWER_DOWN_PARAM_NONE. This fixes a problem on various Amlogic
> Meson SoCs where USB devices are only recognized when plugged in before
> booting Linux. A hot-plugged USB device was not detected even though the
> device got power (my USB thumb drive for example has an LED which lit
> up).
>
> A similar fix was implemented for Rockchip SoCs in commit c216765d3a1def
> ("usb: dwc2: disable power_down on rockchip devices"). That commit
> suggests that a change in the dwc2 driver is the cause because the
> default value for the "hibernate" parameter (which then got renamed to
> "power_down" to support other modes) was changed in the v4.17 merge
> window with:
> commit 6d23ee9caa6790 ("Merge tag 'usb-for-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-testing").
>
> Cc: <[email protected]> # 4.19
> Suggested-by: Christian Hewitt <[email protected]>
> Signed-off-by: Martin Blumenstingl <[email protected]>

Fixed the issue on the Odroid C2 sbc with amlogic meson gxbb soc,
devices are now detected when connected after boot

Tested-by: Brad Harper <[email protected]>

> ---
> drivers/usb/dwc2/params.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/usb/dwc2/params.c b/drivers/usb/dwc2/params.c
> index 7c1b6938f212..38c813b1d203 100644
> --- a/drivers/usb/dwc2/params.c
> +++ b/drivers/usb/dwc2/params.c
> @@ -111,6 +111,7 @@ static void dwc2_set_amlogic_params(struct dwc2_hsotg *hsotg)
> p->phy_type = DWC2_PHY_TYPE_PARAM_UTMI;
> p->ahbcfg = GAHBCFG_HBSTLEN_INCR8 <<
> GAHBCFG_HBSTLEN_SHIFT;
> + p->power_down = DWC2_POWER_DOWN_PARAM_NONE;
> }
>
> static void dwc2_set_amcc_params(struct dwc2_hsotg *hsotg)
>