Re: [PATCH] usb: chipidea: move ci_ulpi_init after the phy initialization

From: Marek Szyprowski
Date: Thu Apr 25 2024 - 15:40:54 EST


Dear All,

On 02.04.2024 08:23, Michael Grzeschik wrote:
> The function ci_usb_phy_init is already handling the
> hw_phymode_configure path which is also only possible after we have
> a valid phy. So we move the ci_ulpi_init after the phy initialization
> to be really sure to be able to communicate with the ulpi phy.
>
> Signed-off-by: Michael Grzeschik <m.grzeschik@xxxxxxxxxxxxxx>

This patch landed in linux-next some time ago as commit 22ffd399e6e7
("usb: chipidea: move ci_ulpi_init after the phy initialization").
Unfortunately it breaks host USB operation on DragonBoard410c
(arch/arm64/boot/dts/qcom/apq8016-sbc.dts). There is no error nor
warning in the kernel log besides the information about deferred probe
on the chipidea controller:

platform ci_hdrc.0: deferred probe pending: (reason unknown)

Tomorrow I will try to investigate which operation during driver probe
triggers it. If there is anything else to check that might help fixing
this issue, let me know.

> ---
> drivers/usb/chipidea/core.c | 8 ++++----
> drivers/usb/chipidea/ulpi.c | 5 -----
> 2 files changed, 4 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/usb/chipidea/core.c b/drivers/usb/chipidea/core.c
> index 835bf2428dc6e..bada13f704b62 100644
> --- a/drivers/usb/chipidea/core.c
> +++ b/drivers/usb/chipidea/core.c
> @@ -1084,10 +1084,6 @@ static int ci_hdrc_probe(struct platform_device *pdev)
> return -ENODEV;
> }
>
> - ret = ci_ulpi_init(ci);
> - if (ret)
> - return ret;
> -
> if (ci->platdata->phy) {
> ci->phy = ci->platdata->phy;
> } else if (ci->platdata->usb_phy) {
> @@ -1142,6 +1138,10 @@ static int ci_hdrc_probe(struct platform_device *pdev)
> goto ulpi_exit;
> }
>
> + ret = ci_ulpi_init(ci);
> + if (ret)
> + return ret;
> +
> ci->hw_bank.phys = res->start;
>
> ci->irq = platform_get_irq(pdev, 0);
> diff --git a/drivers/usb/chipidea/ulpi.c b/drivers/usb/chipidea/ulpi.c
> index dfec07e8ae1d2..89fb51e2c3ded 100644
> --- a/drivers/usb/chipidea/ulpi.c
> +++ b/drivers/usb/chipidea/ulpi.c
> @@ -68,11 +68,6 @@ int ci_ulpi_init(struct ci_hdrc *ci)
> if (ci->platdata->phy_mode != USBPHY_INTERFACE_MODE_ULPI)
> return 0;
>
> - /*
> - * Set PORTSC correctly so we can read/write ULPI registers for
> - * identification purposes
> - */
> - hw_phymode_configure(ci);
>
> ci->ulpi_ops.read = ci_ulpi_read;
> ci->ulpi_ops.write = ci_ulpi_write;
>
> ---
> base-commit: 5bab5dc780c9ed0c69fc2f828015532acf4a7848
> change-id: 20240328-chipidea-phy-misc-b3f2bc814784
>
> Best regards,

Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland