On 31.01.2018 16:57, Andrzej Hajda wrote:
> extcon device is used to detect host/device connection. Since extcon
> OF property is deprecated, alternative method should be added.
> This method uses OF graph bindings to locate extcon.
>
> Signed-off-by: Andrzej Hajda <a.ha...@samsung.com>
Ping, 3.5 months passed.
Regards
Andrzej
> ---
> Hi all,
>
> This patch implements alternative method to get extcon from DWC3.
> The code works but is hacky, as DWC3 must traverse different DT nodes
> to get extcon, in case of TM2 it is USB-PHY and MUIC, but other
> platforms can have different paths.
> I would be glad if it can be merged as is for now, but additional work
> must be done to make it generic.
> I guess on DT binding side it is OK. So the problem should be addressed
> in the code.
> My rough idea is to implement kind of extcon aliases/forwarder mechanism,
> ie. USB-PHY will expect on its output remote port extcon, and it should
> register
> extcon-forwarder pointing to this extcon. This way DWC3 can look for the
> extcon
> on its PHY phandle, and it will receive via forwarding mechanism extcon
> exposed by MUIC.
> As I said this is rough idea for discussion, other propositions are welcome.
>
> Regards
> Andrzej
> ---
> drivers/usb/dwc3/drd.c | 41 ++++++++++++++++++++++++++++-------------
> 1 file changed, 28 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/usb/dwc3/drd.c b/drivers/usb/dwc3/drd.c
> index cc8ab9a8e9d2..eee2eca3d513 100644
> --- a/drivers/usb/dwc3/drd.c
> +++ b/drivers/usb/dwc3/drd.c
> @@ -8,6 +8,7 @@
> */
>
> #include <linux/extcon.h>
> +#include <linux/of_graph.h>
>
> #include "debug.h"
> #include "core.h"
> @@ -38,24 +39,38 @@ static int dwc3_drd_notifier(struct notifier_block *nb,
> return NOTIFY_DONE;
> }
>
> +struct extcon_dev *dwc3_get_extcon(struct dwc3 *dwc)
> +{
> + struct device *dev = dwc->dev;
> + struct device_node *np_phy, *np_conn;
> + struct extcon_dev *edev;
> +
> + if (of_property_read_bool(dev->of_node, "extcon"))
> + return extcon_get_edev_by_phandle(dwc->dev, 0);
> +
> + np_phy = of_parse_phandle(dev->of_node, "phys", 0);
> + np_conn = of_graph_get_remote_node(np_phy, -1, -1);
> + edev = extcon_get_edev_by_of_node(np_conn);
> + of_node_put(np_conn);
> + of_node_put(np_phy);
> +
> + return edev;
> +}
> +
> int dwc3_drd_init(struct dwc3 *dwc)
> {
> int ret;
>
> - if (dwc->dev->of_node) {
> - if (of_property_read_bool(dwc->dev->of_node, "extcon"))
> - dwc->edev = extcon_get_edev_by_phandle(dwc->dev, 0);
> -
> - if (IS_ERR(dwc->edev))
> - return PTR_ERR(dwc->edev);
> + dwc->edev = dwc3_get_extcon(dwc);
> + if (IS_ERR(dwc->edev))
> + return PTR_ERR(dwc->edev);
>
> - dwc->edev_nb.notifier_call = dwc3_drd_notifier;
> - ret = extcon_register_notifier(dwc->edev, EXTCON_USB_HOST,
> - &dwc->edev_nb);
> - if (ret < 0) {
> - dev_err(dwc->dev, "couldn't register cable notifier\n");
> - return ret;
> - }
> + dwc->edev_nb.notifier_call = dwc3_drd_notifier;
> + ret = extcon_register_notifier(dwc->edev, EXTCON_USB_HOST,
> + &dwc->edev_nb);
> + if (ret < 0) {
> + dev_err(dwc->dev, "couldn't register cable notifier\n");
> + return ret;
> }
>
> dwc3_drd_update(dwc);
