linux-kernel - Re: [PATCH 2/2] platform/chrome: typec: Register Type C switches

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <12b56c9e-d8c7-82fa-57c8-7a33236ba188@collabora.com>
Date:   Thu, 30 Apr 2020 00:22:19 +0200
From:   Enric Balletbo i Serra <enric.balletbo@...labora.com>
To:     Prashant Malani <pmalani@...omium.org>,
        linux-kernel@...r.kernel.org
Cc:     heikki.krogerus@...ux.intel.com, twawrzynczak@...omium.org,
        Benson Leung <bleung@...omium.org>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@...r.kernel.org>, Guenter Roeck <groeck@...omium.org>,
        Rob Herring <robh+dt@...nel.org>
Subject: Re: [PATCH 2/2] platform/chrome: typec: Register Type C switches

Hi Prashant,

Thank you for your patch.

On 23/4/20 0:22, Prashant Malani wrote:
> Register Type C mux and switch handles, when provided via firmware
> bindings. These will allow the cros-ec-typec driver, and also alternate
> mode drivers to configure connected Muxes correctly, according to PD
> information retrieved from the Chrome OS EC.
> 
> Signed-off-by: Prashant Malani <pmalani@...omium.org>
> ---
>  drivers/platform/chrome/cros_ec_typec.c | 47 +++++++++++++++++++++++++
>  1 file changed, 47 insertions(+)
> 
> diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
> index eda57db26f8d..324ead297c4d 100644
> --- a/drivers/platform/chrome/cros_ec_typec.c
> +++ b/drivers/platform/chrome/cros_ec_typec.c
> @@ -14,6 +14,8 @@
>  #include <linux/platform_data/cros_usbpd_notify.h>
>  #include <linux/platform_device.h>
>  #include <linux/usb/typec.h>
> +#include <linux/usb/typec_mux.h>
> +#include <linux/usb/role.h>
>  
>  #define DRV_NAME "cros-ec-typec"
>  
> @@ -25,6 +27,9 @@ struct cros_typec_port {
>  	struct typec_partner *partner;
>  	/* Port partner PD identity info. */
>  	struct usb_pd_identity p_identity;
> +	struct typec_switch *ori_sw;
> +	struct typec_mux *mux;
> +	struct usb_role_switch *role_sw;
>  };
>  
>  /* Platform-specific data for the Chrome OS EC Type C controller. */
> @@ -84,6 +89,40 @@ static int cros_typec_parse_port_props(struct typec_capability *cap,
>  	return 0;
>  }
>  
> +static int cros_typec_get_switch_handles(struct cros_typec_port *port,
> +					 struct fwnode_handle *fwnode,
> +					 struct device *dev)
> +{
> +	port->mux = fwnode_typec_mux_get(fwnode, NULL);
> +	if (IS_ERR(port->mux)) {

Should you return an error if NULL is returned (IS_ERR_OR_NULL) ? I think that
fwnode_typec_mux_get can return NULL too.


> +		dev_info(dev, "Mux handle not found.\n");
> +		goto mux_err;
> +	}
> +
> +	port->ori_sw = fwnode_typec_switch_get(fwnode);
> +	if (IS_ERR(port->ori_sw)) {

ditto

> +		dev_info(dev, "Orientation switch handle not found.\n");
> +		goto ori_sw_err;
> +	}
> +
> +	port->role_sw = fwnode_usb_role_switch_get(fwnode);
> +	if (IS_ERR(port->role_sw)) {

ditto

> +		dev_info(dev, "USB role switch handle not found.\n");
> +		goto role_sw_err;
> +	}
> +
> +	return 0;
> +
> +role_sw_err:
> +	usb_role_switch_put(port->role_sw);
> +ori_sw_err:
> +	typec_switch_put(port->ori_sw);
> +mux_err:
> +	typec_mux_put(port->mux);
> +
> +	return -ENODEV;
> +}
> +
>  static void cros_unregister_ports(struct cros_typec_data *typec)
>  {
>  	int i;
> @@ -91,6 +130,9 @@ static void cros_unregister_ports(struct cros_typec_data *typec)
>  	for (i = 0; i < typec->num_ports; i++) {
>  		if (!typec->ports[i])
>  			continue;
> +		usb_role_switch_put(typec->ports[i]->role_sw);
> +		typec_switch_put(typec->ports[i]->ori_sw);
> +		typec_mux_put(typec->ports[i]->mux);
>  		typec_unregister_port(typec->ports[i]->port);
>  	}
>  }
> @@ -153,6 +195,11 @@ static int cros_typec_init_ports(struct cros_typec_data *typec)
>  			ret = PTR_ERR(cros_port->port);
>  			goto unregister_ports;
>  		}
> +
> +		ret = cros_typec_get_switch_handles(cros_port, fwnode, dev);
> +		if (ret)
> +			dev_info(dev, "No switch control for port %d\n",
> +				 port_num);

When drivers are working, they should not spit out any messages, make
this dev_dbg() at the most. Be quiet, please.


>  	}
>  
>  	return 0;
>