From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chanwoo Choi Subject: Re: [v5 PATCH 1/5] extcon: Add Type-C and DP support Date: Wed, 13 Jul 2016 11:05:39 +0900 Message-ID: <5785A1F3.1020703@samsung.com> References: <1468336188-565-1-git-send-email-zyw@rock-chips.com> <1468336188-565-2-git-send-email-zyw@rock-chips.com> <57859532.1010002@samsung.com> <57859BDA.7080309@rock-chips.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-reply-to: <57859BDA.7080309@rock-chips.com> Sender: linux-kernel-owner@vger.kernel.org To: Chris Zhong , dianders@chromium.org, tfiga@chromium.org, heiko@sntech.de, yzq@rock-chips.com, groeck@chromium.org, myungjoo.ham@samsung.com, wulf@rock-chips.com, marcheu@chromium.org Cc: linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org List-Id: linux-rockchip.vger.kernel.org Hi Chris, On 2016=EB=85=84 07=EC=9B=94 13=EC=9D=BC 10:39, Chris Zhong wrote: > Hi Chanwoo Choi >=20 >=20 > On 07/13/2016 09:11 AM, Chanwoo Choi wrote: >> Hi Chris, >> >> I'm now developing the extcon property on extcon-test branch. >> But, it has not been completed. >> >> On next version, I'll remove the notification about extcon property >> and only support the following two functions. >> - extcon_set_cable_property() >> - extcon_get_cable_property() >> >> Because the number of properties would be risen and the all properti= es >> depend on the specific external connector(e.g., EXTCON_PROP_USB_VBUS >> depend on the EXTCON_TYPE_USB type). When the specific external conn= ector >> is detached, extcon framework should make the property state as defa= ult state. >=20 > Yes, I think getting the notification from cable state is enough, act= ually I am using it like you said. OK.=20 >=20 >> >> It may send the too many notification for extcon property. >> For example, Assume that EXTCON_TYPE_USB has the over 20 properties, >> when EXTCON_USB or EXTCON_USB_HOST is detached, extcon should send >> the notification for the over 20 properties and one more notificaito= n >> for state of external connector. >> >> So, I'll send the RFC patchset without the notification of proerty. >> >> Lastly, >> I have a comment on below. >> >> Thanks, >> Chanwoo Choi >> >> On 2016=EB=85=84 07=EC=9B=94 13=EC=9D=BC 00:09, Chris Zhong wrote: >>> Add EXTCON_DISP_DP for the Display external connector. For Type-C >>> connector the DisplayPort can work as an Alternate Mode(VESA Displa= yPort >>> Alt Mode on USB Type-C Standard). The Type-C support both normal an= d >>> flipped orientation, so add a property to extcon. >>> >>> Signe-off-by: Chris Zhong >>> >>> Signed-off-by: Chris Zhong >>> --- >>> >>> Changes in v5: >>> - support get property >>> >>> Changes in v4: None >>> Changes in v3: None >>> Changes in v2: None >>> Changes in v1: None >>> >>> drivers/extcon/extcon.c | 28 ++++++++++++++++++++++++++++ >>> include/linux/extcon.h | 13 +++++++++++++ >>> 2 files changed, 41 insertions(+) >>> >>> diff --git a/drivers/extcon/extcon.c b/drivers/extcon/extcon.c >>> index a1117db..2591b28 100644 >>> --- a/drivers/extcon/extcon.c >>> +++ b/drivers/extcon/extcon.c >>> @@ -157,6 +157,11 @@ struct __extcon_info { >>> .id =3D EXTCON_DISP_VGA, >>> .name =3D "VGA", >>> }, >>> + [EXTCON_DISP_DP] =3D { >>> + .type =3D EXTCON_TYPE_DISP, >>> + .id =3D EXTCON_DISP_DP, >>> + .name =3D "DP", >>> + }, >>> /* Miscellaneous external connector */ >>> [EXTCON_DOCK] =3D { >>> @@ -270,6 +275,7 @@ static bool is_extcon_property_supported(unsign= ed int id, >>> switch (prop) { >>> case EXTCON_PROP_USB_ID: >>> case EXTCON_PROP_USB_VBUS: >>> + case EXTCON_PROP_TYPEC_POLARITY: >>> return true; >>> default: >>> break; >>> @@ -286,6 +292,8 @@ static bool is_extcon_property_supported(unsign= ed int id, >>> } >>> case EXTCON_TYPE_DISP: >>> switch (prop) { >>> + case EXTCON_PROP_TYPEC_POLARITY: >> Should EXTCON_PROP_TYPEC_POLARITY property add to both EXTCON_TYPE_U= SB and EXTCON_TYP_DISP? >> EXTCON_PROP_TYPEC_POLARITY is the property of USB C-type? >=20 > it is for USB Type-C, But at Display Port alt mode, both EXTCON_USB a= nd EXTCON_USB_HOST may be detached. Does it support set the property to= a detached cable, if so, I think move this case to EXTCON_USB is fine. One external connector can set the state of one more external connector if the one connector support the various functions. =46or example, EXTCON_USB and EXTCON_CHG_USB_SDP The existing extcon driver[1](e.g., max14577/max77693 etc.) set the sta= te of both EXTCON_USB and EXTCON_CHG_USB_SDP connector at the same time when usb cable is attached. Because in this case, the usb connector use= s as both power supply(EXTCON_CHG_USB_SDP) and data transfer(EXTCON_USB= ). [1] https://git.kernel.org/cgit/linux/kernel/git/chanwoo/extcon.git/com= mit/?h=3Dextcon-next&id=3D8b45b6a0741678902810d7be95e635c210fbb198 So, DP Alt mode uses the USB Type-C. So, When USB C-type connector is a= ttached for DP Alt mode, Maybe, you can set the following two state of connector and one propert= y: - extcon_set_cable_state(edev, [EXTCON_USB or EXTCON_USB_HOST], 1); - extcon_set_cable_state(edev, EXTCON_DISP_DP, 1); - extcon_set_cable_state(edev, [EXTCON_USB or EXTCON_USB_HOST], EXTCON_= PROP_TYPEC_POLARITY, 0 or 1); Thanks, Chanwoo Choi