Re: [PATCH v2 4/7] usb: cdns3-ti: add suspend/resume procedures for J7200

From: Krzysztof Kozlowski
Date: Mon Nov 20 2023 - 12:31:45 EST


On 20/11/2023 18:06, Théo Lebrun wrote:
> Hardware initialisation is only done at probe. The J7200 USB controller
> is reset at resume because of power-domains toggling off & on. We
> therefore reconfigure the hardware at resume.
>
> Reuse the newly extracted cdns_ti_init_hw() function that contains the
> register write sequence.
>
> Only focus J7200 as other SoC are untested. If the controller does not
> reset we do not want to redo reg writes.
>
> Signed-off-by: Théo Lebrun <theo.lebrun@xxxxxxxxxxx>
> ---
> drivers/usb/cdns3/cdns3-ti.c | 24 +++++++++++++++++++++++-
> 1 file changed, 23 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/cdns3/cdns3-ti.c b/drivers/usb/cdns3/cdns3-ti.c
> index d4232b440e4e..84f93c2fcd5c 100644
> --- a/drivers/usb/cdns3/cdns3-ti.c
> +++ b/drivers/usb/cdns3/cdns3-ti.c
> @@ -58,6 +58,7 @@ struct cdns_ti {
> struct clk *usb2_refclk;
> struct clk *lpm_clk;
> int usb2_refclk_rate_code;
> + bool reset_on_resume;
> };
>
> static const int cdns_ti_rate_table[] = { /* in KHZ */
> @@ -172,6 +173,7 @@ static int cdns_ti_probe(struct platform_device *pdev)
> data->usb2_refclk_rate_code = i;
> data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
> data->usb2_only = device_property_read_bool(dev, "ti,usb2-only");
> + data->reset_on_resume = of_device_is_compatible(node, "ti,j7200-usb");

No, use driver data for this. Don't put compatibles in the code. It
makes it unmanageable soon.

I am repeating this issue from time to time :/

Best regards,
Krzysztof