| Message ID | 20220301132010.115258-1-alvin@pqrs.dk |
|---|---|
| Headers | show |
| Series | usb: typec: add drivers for TUSB320xA and TS5USBA224 | expand |
On Mon, Mar 07, 2022 at 10:17:04PM +0000, Alvin Šipraga wrote: > Hi Heikki, > > Heikki Krogerus <heikki.krogerus@linux.intel.com> writes: > > > Hi, > > > > On Tue, Mar 01, 2022 at 02:20:07PM +0100, Alvin Šipraga wrote: > >> From: Alvin Šipraga <alsi@bang-olufsen.dk> > >> > >> The TUSB320LA and TUSB320HA (or LAI, HAI) chips are I2C controlled > >> non-PD Type-C port controllers. They support detection of cable > >> orientation, port attachment state, and role, including Audio Accessory > >> and Debug Accessory modes. Add a typec class driver for this family. > >> > >> Note that there already exists an extcon driver for the TUSB320 (a > >> slightly older revision that does not support setting role preference or > >> disabling the CC state machine). This driver is loosely based on that > >> one. > > > > This looked mostly OK to me. There is one question below. > > > > <snip> > > > >> +static int tusb320xa_check_signature(struct tusb320xa *tusb) > >> +{ > >> + static const char sig[] = { '\0', 'T', 'U', 'S', 'B', '3', '2', '0' }; > >> + unsigned int val; > >> + int i, ret; > >> + > >> + mutex_lock(&tusb->lock); > >> + > >> + for (i = 0; i < sizeof(sig); i++) { > >> + ret = regmap_read(tusb->regmap, sizeof(sig) - 1 - i, &val); > >> + if (ret) > >> + goto done; > >> + > >> + if (val != sig[i]) { > >> + dev_err(tusb->dev, "signature mismatch!\n"); > >> + ret = -ENODEV; > >> + goto done; > >> + } > >> + } > >> + > >> +done: > >> + mutex_unlock(&tusb->lock); > >> + > >> + return ret; > >> +} > > > > Couldn't that be done with a single read? > > > > char sig[8]; > > u64 val; > > > > strcpy(sig, "TUSB320") > > > > mutex_lock(&tusb->lock); > > > > ret = regmap_raw_read(tusb->regmap, 0, &val, sizeof(val)); > > ... > > if (val != cpu_to_le64(*(u64 *)sig)) { > > ... > > > > Something like that? > > I think it's a bit cryptic - are you sure it's worth it just to save 8 > one-off regmap_read()s? I could also just remove this check... I see it > mostly as a courtesy to the user in case the I2C address in his device > tree mistakenly points to some other unsuspecting chip. > > BTW, do you have any feedback on the device tree bindings of this > series? Rob had some questions and I am not sure that my proposed > bindings are fully aligned with the typec subsystem expectations. Any > feedback would be welcome. I don't think I understand DT well enough to comment. I'm not completely sure what he's asking.. > I will wait for more comments and send a v2 in ~a week. thanks,
Heikki Krogerus <heikki.krogerus@linux.intel.com> writes: > On Mon, Mar 07, 2022 at 10:17:04PM +0000, Alvin Šipraga wrote: >> Hi Heikki, >> >> Heikki Krogerus <heikki.krogerus@linux.intel.com> writes: >> >> > Hi, >> > >> > On Tue, Mar 01, 2022 at 02:20:07PM +0100, Alvin Šipraga wrote: >> >> From: Alvin Šipraga <alsi@bang-olufsen.dk> >> >> >> >> The TUSB320LA and TUSB320HA (or LAI, HAI) chips are I2C controlled >> >> non-PD Type-C port controllers. They support detection of cable >> >> orientation, port attachment state, and role, including Audio Accessory >> >> and Debug Accessory modes. Add a typec class driver for this family. >> >> >> >> Note that there already exists an extcon driver for the TUSB320 (a >> >> slightly older revision that does not support setting role preference or >> >> disabling the CC state machine). This driver is loosely based on that >> >> one. >> > >> > This looked mostly OK to me. There is one question below. >> > >> > <snip> >> > >> >> +static int tusb320xa_check_signature(struct tusb320xa *tusb) >> >> +{ >> >> + static const char sig[] = { '\0', 'T', 'U', 'S', 'B', '3', '2', '0' }; >> >> + unsigned int val; >> >> + int i, ret; >> >> + >> >> + mutex_lock(&tusb->lock); >> >> + >> >> + for (i = 0; i < sizeof(sig); i++) { >> >> + ret = regmap_read(tusb->regmap, sizeof(sig) - 1 - i, &val); >> >> + if (ret) >> >> + goto done; >> >> + >> >> + if (val != sig[i]) { >> >> + dev_err(tusb->dev, "signature mismatch!\n"); >> >> + ret = -ENODEV; >> >> + goto done; >> >> + } >> >> + } >> >> + >> >> +done: >> >> + mutex_unlock(&tusb->lock); >> >> + >> >> + return ret; >> >> +} >> > >> > Couldn't that be done with a single read? >> > >> > char sig[8]; >> > u64 val; >> > >> > strcpy(sig, "TUSB320") >> > >> > mutex_lock(&tusb->lock); >> > >> > ret = regmap_raw_read(tusb->regmap, 0, &val, sizeof(val)); >> > ... >> > if (val != cpu_to_le64(*(u64 *)sig)) { >> > ... >> > >> > Something like that? >> >> I think it's a bit cryptic - are you sure it's worth it just to save 8 >> one-off regmap_read()s? I could also just remove this check... I see it >> mostly as a courtesy to the user in case the I2C address in his device >> tree mistakenly points to some other unsuspecting chip. >> >> BTW, do you have any feedback on the device tree bindings of this >> series? Rob had some questions and I am not sure that my proposed >> bindings are fully aligned with the typec subsystem expectations. Any >> feedback would be welcome. > > I don't think I understand DT well enough to comment. I'm not > completely sure what he's asking.. OK, no problem! Thanks for your reply. Kind regards, Alvin > >> I will wait for more comments and send a v2 in ~a week. > > thanks,
From: Alvin Šipraga <alsi@bang-olufsen.dk> This series adds a new typec class driver for the TUSB320xA family of Type-C port controllers and a typec_mux class driver for the TS5USBA224 switch mux. This series was bourne out of frustration with the existing extcon driver for the TUSB320, which did not offer a convenient driver model for the Audio Accessory mode muxing offered by the TS5USBA224. I found the typec subsystem to be more suitable. I have tested this on my i.MX8MM platform with USB OTG support and it works as desired. However I am not very familiar with this part of the kernel, so I welcome your critical feedback to this series. Thanks in advance. Alvin Šipraga (4): dt-bindings: usb: add TUSB320xA Type-C port controller dt-bindings: usb: add TS5USBA224 USB/Audio switch mux usb: typec: add TUSB320xA driver usb: typec: mux: add TS5USBA224 driver .../bindings/usb/ti,ts5usba224.yaml | 56 ++ .../devicetree/bindings/usb/ti,tusb320xa.yaml | 78 +++ drivers/usb/typec/Kconfig | 12 + drivers/usb/typec/Makefile | 1 + drivers/usb/typec/mux/Kconfig | 10 + drivers/usb/typec/mux/Makefile | 1 + drivers/usb/typec/mux/ts5usba224.c | 102 ++++ drivers/usb/typec/tusb320xa.c | 517 ++++++++++++++++++ 8 files changed, 777 insertions(+) create mode 100644 Documentation/devicetree/bindings/usb/ti,ts5usba224.yaml create mode 100644 Documentation/devicetree/bindings/usb/ti,tusb320xa.yaml create mode 100644 drivers/usb/typec/mux/ts5usba224.c create mode 100644 drivers/usb/typec/tusb320xa.c