Re: [PATCH v4 2/2] usb: phy: Add USB3 PHY support for Intel LGM SoC

From: Philipp Zabel
Date: Wed Jun 17 2020 - 05:23:16 EST


Hi Vadivel,

On Wed, 2020-06-17 at 11:58 +0800, Ramuthevar,Vadivel MuruganX wrote:
> From: Ramuthevar Vadivel Murugan <vadivel.muruganx.ramuthevar@xxxxxxxxxxxxxxx>
>
> Add support for USB PHY on Intel LGM SoC.
>
> Signed-off-by: Ramuthevar Vadivel Murugan <vadivel.muruganx.ramuthevar@xxxxxxxxxxxxxxx>
> ---
> drivers/usb/phy/Kconfig | 11 ++
> drivers/usb/phy/Makefile | 1 +
> drivers/usb/phy/phy-lgm-usb.c | 275 ++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 287 insertions(+)
> create mode 100644 drivers/usb/phy/phy-lgm-usb.c
>
[...]
> diff --git a/drivers/usb/phy/phy-lgm-usb.c b/drivers/usb/phy/phy-lgm-usb.c
> new file mode 100644
> index 000000000000..3da772dfd736
> --- /dev/null
> +++ b/drivers/usb/phy/phy-lgm-usb.c
> @@ -0,0 +1,275 @@
[...]
> + for (i = 0; i < ARRAY_SIZE(CTL_RESETS); i++) {
> + resets[i] = devm_reset_control_get_exclusive(dev, CTL_RESETS[i]);
> + if (IS_ERR(resets[i])) {
> + dev_err(dev, "%s reset not found\n", CTL_RESETS[i]);
> + return PTR_ERR(resets[i]);
> + }
> + }
> +
> + for (i = 0; i < ARRAY_SIZE(PHY_RESETS); i++) {
> + ta->resets[i] = devm_reset_control_get_exclusive(dev, PHY_RESETS[i]);
> + if (IS_ERR(ta->resets[i])) {
> + dev_err(dev, "%s reset not found\n", PHY_RESETS[i]);
> + return PTR_ERR(ta->resets[i]);
> + }
> + }
> +
> + for (i = 0; i < ARRAY_SIZE(CTL_RESETS); i++)
> + reset_control_assert(resets[i]);
> +
> + for (i = 0; i < ARRAY_SIZE(PHY_RESETS); i++)
> + reset_control_assert(ta->resets[i]);
> + /*
> + * Out-of-band reset of the controller after PHY reset will cause
> + * controller malfunctioning, so we should use in-band controller
> + * reset only and leave the controller de-asserted here.
> + */
> + for (i = 0; i < ARRAY_SIZE(CTL_RESETS); i++)
> + reset_control_deassert(resets[i]);

This driver could probably benefit from a reset_bulk API similar to the
clk_bulk and regulator_bulk APIs, but that doesn't exist yet.

For the reset handling in this driver,

Reviewed-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>

regards
Philipp