-----Original Message----- From: Kai-Heng Feng [mailto:kai.heng.feng@xxxxxxxxxxxxx] Sent: Monday, January 21, 2019 12:28 PM To: 廖崇榮 Cc: Benjamin Tissoires; Dmitry Torokhov; open list:HID CORE LAYER; lkml Subject: Re: [PATCH 1/1] Input: elantech: Use SMBus based on bus info > On Jan 18, 2019, at 17:29, 廖崇榮 <kt.liao@xxxxxxxxxx> wrote: > > > > -----Original Message----- > From: Kai Heng Feng [mailto:kai.heng.feng@xxxxxxxxxxxxx] > Sent: Friday, January 18, 2019 12:15 AM > To: Benjamin Tissoires > Cc: Dmitry Torokhov; 廖崇榮; open list:HID CORE LAYER; lkml > Subject: Re: [PATCH 1/1] Input: elantech: Use SMBus based on bus info > > > >> On Jan 17, 2019, at 10:42 PM, Benjamin Tissoires > <benjamin.tissoires@xxxxxxxxxx> wrote: >> >> Hi Kai-Heng, >> >> On Thu, Jan 17, 2019 at 10:30 AM Kai-Heng Feng >> <kai.heng.feng@xxxxxxxxxxxxx> wrote: >>> >>> There are some new HP laptops with Elantech touchpad don't support >>> multitouch. >>> >>> Both ETP_BUS_SMB_HST_NTFY_ONLY and ETP_BUS_PS2_SMB_HST_NTFY devices >>> can use SMBus to support 5 fingers touch, so we need to chech them too. >>> >>> So use elantech_use_host_notify() to do a more thouroughly check. >>> >>> Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> >>> --- >>> drivers/input/mouse/elantech.c | 58 >>> +++++++++++++++++----------------- >>> 1 file changed, 29 insertions(+), 29 deletions(-) >>> >>> diff --git a/drivers/input/mouse/elantech.c >>> b/drivers/input/mouse/elantech.c index 9fe075c137dc..5bcf1c147eb1 >>> 100644 >>> --- a/drivers/input/mouse/elantech.c >>> +++ b/drivers/input/mouse/elantech.c >>> @@ -1799,6 +1799,34 @@ static int elantech_create_smbus(struct >>> psmouse > *psmouse, >>> leave_breadcrumbs); } >>> >>> +static bool elantech_use_host_notify(struct psmouse *psmouse, >>> + struct elantech_device_info >>> +*info) { >>> + if (ETP_NEW_IC_SMBUS_HOST_NOTIFY(info->fw_version)) >>> + return true; >>> + >>> + switch (info->bus) { >>> + case ETP_BUS_PS2_ONLY: >>> + /* expected case */ >>> + break; >>> + case ETP_BUS_SMB_ALERT_ONLY: >>> + /* fall-through */ >>> + case ETP_BUS_PS2_SMB_ALERT: >>> + psmouse_dbg(psmouse, "Ignoring SMBus provider >>> + through > alert protocol.\n"); >>> + break; >>> + case ETP_BUS_SMB_HST_NTFY_ONLY: >>> + /* fall-through */ >>> + case ETP_BUS_PS2_SMB_HST_NTFY: >>> + return true; >>> + default: >>> + psmouse_dbg(psmouse, >>> + "Ignoring SMBus bus provider %d.\n", >>> + info->bus); >>> + } >>> + >>> + return false; >>> +} >>> + >>> /** >>> * elantech_setup_smbus - called once the PS/2 devices are enumerated >>> * and decides to instantiate a SMBus InterTouch device. >>> @@ -1818,7 +1846,7 @@ static int elantech_setup_smbus(struct psmouse > *psmouse, >>> * i2c_blacklist_pnp_ids. >>> * Old ICs are up to the user to decide. >>> */ >>> - if (!ETP_NEW_IC_SMBUS_HOST_NOTIFY(info->fw_version) || >>> + if (!elantech_use_host_notify(psmouse, info) || >> >> That was my initial approach of the series, but I ended up being more >> conservative as this would flip all of the existing elantech SMBUS >> capable touchpads to use elan_i2c. >> And I didn't want to deal with 4/5 year old laptops that suddenly broke. >> >> So I wonder if you can restrict this default change to the recent >> laptops (let's say 2018+). Maybe by looking at their FW version or >> something else in the DMI? > > It was KT who told me that I should use ETP_BUS_PS2_SMB_HST_NTFY. > > As for date, KT still knows better than me. > > KT, > Can you name a year which is safe enough to enable SMBus? > > I have discussed it internally. > The internal rule for FW's SMbus implementation is stable after 2018 > If you meet some special case, please let me know. Thanks for the info. I’ll use this for the V2 patch. > > BTW, The SMbus supporting is requested by HP this time, and there are > plenty of HP laptop use old IC which doesn't meet " > ETP_NEW_IC_SMBUS_HOST_NOTIFY”. One more question, does ETP_BUS_SMB_HST_NTFY_ONLY means it should stick to SMBus, because it doesn’t support PS/2? I’d like to merge all checks into elantech_use_host_notify() but ETP_BUS_SMB_HST_NTFY_ONLY caught my attention. ETP_BUS_SMB_HST_NTFY_ONLY is for our previous planning but it never happen so far, and it won't happen in the future. There are two cases for our released touchpad and they are " ETP_BUS_PS2_ONLY" and " ETP_BUS_PS2_SMB_HST_NTFY". Thanks KT Kai-Heng > > Elan touchpad works well in PS/2 for HP, because it don't support > TrackPoint. > You may let old HP platform work as PS/2 for safety. > > Thanks > KT > > Kai-Heng > >> >> Cheers, >> Benjamin >> >>> psmouse_matches_pnp_id(psmouse, > i2c_blacklist_pnp_ids)) >>> return -ENXIO; >>> } >>> @@ -1838,34 +1866,6 @@ static int elantech_setup_smbus(struct >>> psmouse > *psmouse, >>> return 0; >>> } >>> >>> -static bool elantech_use_host_notify(struct psmouse *psmouse, >>> - struct elantech_device_info *info) >>> -{ >>> - if (ETP_NEW_IC_SMBUS_HOST_NOTIFY(info->fw_version)) >>> - return true; >>> - >>> - switch (info->bus) { >>> - case ETP_BUS_PS2_ONLY: >>> - /* expected case */ >>> - break; >>> - case ETP_BUS_SMB_ALERT_ONLY: >>> - /* fall-through */ >>> - case ETP_BUS_PS2_SMB_ALERT: >>> - psmouse_dbg(psmouse, "Ignoring SMBus provider through > alert protocol.\n"); >>> - break; >>> - case ETP_BUS_SMB_HST_NTFY_ONLY: >>> - /* fall-through */ >>> - case ETP_BUS_PS2_SMB_HST_NTFY: >>> - return true; >>> - default: >>> - psmouse_dbg(psmouse, >>> - "Ignoring SMBus bus provider %d.\n", >>> - info->bus); >>> - } >>> - >>> - return false; >>> -} >>> - >>> int elantech_init_smbus(struct psmouse *psmouse) { >>> struct elantech_device_info info; >>> -- >>> 2.17.1 >
