Re: [PATCH v3 4/8] qcom: pmic_glink_altmode: add retimer-switch support

[Heikki Krogerus]

On Tue, Jun 13, 2023 at 09:55:57AM +0200, Neil Armstrong wrote:
> Some boards have a retimer/redriver between the SuperSpeed
> PHY and the USB-C connector to compensates signal integrity
> losses mainly due to PCB & transmission cables.
> 
> Add support for an optional retimer-switch in the USB-C
> connector graph.
> 
> Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>

Acked-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>

> ---
>  drivers/soc/qcom/pmic_glink_altmode.c | 43 +++++++++++++++++++++++++++++++++++
>  1 file changed, 43 insertions(+)
> 
> diff --git a/drivers/soc/qcom/pmic_glink_altmode.c b/drivers/soc/qcom/pmic_glink_altmode.c
> index 007d308e2f15..41d732f5b647 100644
> --- a/drivers/soc/qcom/pmic_glink_altmode.c
> +++ b/drivers/soc/qcom/pmic_glink_altmode.c
> @@ -15,6 +15,7 @@
>  #include <linux/usb/typec_altmode.h>
>  #include <linux/usb/typec_dp.h>
>  #include <linux/usb/typec_mux.h>
> +#include <linux/usb/typec_retimer.h>
>  
>  #include <linux/soc/qcom/pmic_glink.h>
>  
> @@ -68,6 +69,8 @@ struct pmic_glink_altmode_port {
>  	struct typec_switch *typec_switch;
>  	struct typec_mux *typec_mux;
>  	struct typec_mux_state state;
> +	struct typec_retimer *typec_retimer;
> +	struct typec_retimer_state retimer_state;
>  	struct typec_altmode dp_alt;
>  
>  	struct work_struct work;
> @@ -157,6 +160,14 @@ static void pmic_glink_altmode_enable_dp(struct pmic_glink_altmode *altmode,
>  	ret = typec_mux_set(port->typec_mux, &port->state);
>  	if (ret)
>  		dev_err(altmode->dev, "failed to switch mux to DP\n");
> +
> +	port->retimer_state.alt = &port->dp_alt;
> +	port->retimer_state.data = &dp_data;
> +	port->retimer_state.mode = TYPEC_MODAL_STATE(mode);
> +
> +	ret = typec_retimer_set(port->typec_retimer, &port->retimer_state);
> +	if (ret)
> +		dev_err(altmode->dev, "failed to setup retimer to DP\n");
>  }
>  
>  static void pmic_glink_altmode_enable_usb(struct pmic_glink_altmode *altmode,
> @@ -171,6 +182,14 @@ static void pmic_glink_altmode_enable_usb(struct pmic_glink_altmode *altmode,
>  	ret = typec_mux_set(port->typec_mux, &port->state);
>  	if (ret)
>  		dev_err(altmode->dev, "failed to switch mux to USB\n");
> +
> +	port->retimer_state.alt = NULL;
> +	port->retimer_state.data = NULL;
> +	port->retimer_state.mode = TYPEC_STATE_USB;
> +
> +	ret = typec_retimer_set(port->typec_retimer, &port->retimer_state);
> +	if (ret)
> +		dev_err(altmode->dev, "failed to setup retimer to USB\n");
>  }
>  
>  static void pmic_glink_altmode_safe(struct pmic_glink_altmode *altmode,
> @@ -185,6 +204,14 @@ static void pmic_glink_altmode_safe(struct pmic_glink_altmode *altmode,
>  	ret = typec_mux_set(port->typec_mux, &port->state);
>  	if (ret)
>  		dev_err(altmode->dev, "failed to switch mux to safe mode\n");
> +
> +	port->retimer_state.alt = NULL;
> +	port->retimer_state.data = NULL;
> +	port->retimer_state.mode = TYPEC_STATE_SAFE;
> +
> +	ret = typec_retimer_set(port->typec_retimer, &port->retimer_state);
> +	if (ret)
> +		dev_err(altmode->dev, "failed to setup retimer to USB\n");
>  }
>  
>  static void pmic_glink_altmode_worker(struct work_struct *work)
> @@ -347,6 +374,11 @@ static const struct drm_bridge_funcs pmic_glink_altmode_bridge_funcs = {
>  	.attach = pmic_glink_altmode_attach,
>  };
>  
> +static void pmic_glink_altmode_put_retimer(void *data)
> +{
> +	typec_retimer_put(data);
> +}
> +
>  static void pmic_glink_altmode_put_mux(void *data)
>  {
>  	typec_mux_put(data);
> @@ -453,6 +485,17 @@ static int pmic_glink_altmode_probe(struct auxiliary_device *adev,
>  		if (ret)
>  			return ret;
>  
> +		alt_port->typec_retimer = fwnode_typec_retimer_get(fwnode);
> +		if (IS_ERR(alt_port->typec_retimer))
> +			return dev_err_probe(dev, PTR_ERR(alt_port->typec_retimer),
> +					     "failed to acquire retimer-switch for port: %d\n",
> +					     port);
> +
> +		ret = devm_add_action_or_reset(dev, pmic_glink_altmode_put_retimer,
> +					       alt_port->typec_retimer);
> +		if (ret)
> +			return ret;
> +
>  		alt_port->typec_switch = fwnode_typec_switch_get(fwnode);
>  		if (IS_ERR(alt_port->typec_switch))
>  			return dev_err_probe(dev, PTR_ERR(alt_port->typec_switch),
> 
> -- 
> 2.34.1

-- 
heikki