| Message ID | 20180320032331.29865-3-thierry.escande@linaro.org |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | Bluetooth: hci_qca: Add serdev support | expand |
Hi Thierry, > Add binding document for serial bluetooth chips using Qualcomm protocol. > > Signed-off-by: Thierry Escande <thierry.escande@linaro.org> > --- > > v5: > - Rename 'bt-disable-n' gpio as 'enable' > > v4: > - Move bt-disable-n-gpios to required properties section > - Add clocks and pinctrl-0 as required properties > > v3: no change > v2: no change > > .../devicetree/bindings/net/qualcomm-bluetooth.txt | 34 ++++++++++++++++++++++ > 1 file changed, 34 insertions(+) > create mode 100644 Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt > > diff --git a/Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt b/Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt > new file mode 100644 > index 000000000000..bbc2973634b2 > --- /dev/null > +++ b/Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt > @@ -0,0 +1,34 @@ > +Qualcomm Bluetooth Chips > +--------------------- > + > +This documents the binding structure and common properties for serial > +attached Qualcomm devices. > + > +Serial attached Qualcomm devices shall be a child node of the host UART > +device the slave device is attached to. > + > +Required properties: > + - compatible: should contain one of the following: > + * "qcom,qca6174-bt" > + - enable-gpios: gpio specifier used to enable chip > + - pinctrl-0: pin phandle for bt_en gpio > + - clocks: clock phandle for SUSCLK_32KHZ if I compare this with broadcom-bluetooth.txt or ti-bluetooth.txt then besides compatible, everything else is optional. The nokia-bluetooth.txt has everything required, but that is also a really specific platform. Can we be less restrictive for a QCA general purpose chip? > + > +Example: > + > +serial@7570000 { > + pinctrl-names = "default", "sleep"; > + pinctrl-0 = <&blsp1_uart1_default>; > + pinctrl-1 = <&blsp1_uart1_sleep>; > + > + bluetooth { > + compatible = "qcom,qca6174-bt"; > + > + enable-gpios = <&pm8994_gpios 19 GPIO_ACTIVE_HIGH>; > + > + pinctrl-names = "default"; > + pinctrl-0 = <&bt_en_pin_a>; This one I do not understand and you might want to shed some light into why this is done that way. > + > + clocks = <&divclk4>; No clock-names? Regards Marcel -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Marcel, On 20/03/2018 16:58, Marcel Holtmann wrote: > Hi Thierry, > >> Add binding document for serial bluetooth chips using Qualcomm protocol. >> >> Signed-off-by: Thierry Escande <thierry.escande@linaro.org> >> --- >> >> v5: >> - Rename 'bt-disable-n' gpio as 'enable' >> >> v4: >> - Move bt-disable-n-gpios to required properties section >> - Add clocks and pinctrl-0 as required properties >> >> v3: no change >> v2: no change >> >> .../devicetree/bindings/net/qualcomm-bluetooth.txt | 34 ++++++++++++++++++++++ >> 1 file changed, 34 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt >> >> diff --git a/Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt b/Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt >> new file mode 100644 >> index 000000000000..bbc2973634b2 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt >> @@ -0,0 +1,34 @@ >> +Qualcomm Bluetooth Chips >> +--------------------- >> + >> +This documents the binding structure and common properties for serial >> +attached Qualcomm devices. >> + >> +Serial attached Qualcomm devices shall be a child node of the host UART >> +device the slave device is attached to. >> + >> +Required properties: >> + - compatible: should contain one of the following: >> + * "qcom,qca6174-bt" >> + - enable-gpios: gpio specifier used to enable chip >> + - pinctrl-0: pin phandle for bt_en gpio >> + - clocks: clock phandle for SUSCLK_32KHZ > > if I compare this with broadcom-bluetooth.txt or ti-bluetooth.txt then besides compatible, everything else is optional. The nokia-bluetooth.txt has everything required, but that is also a really specific platform. > > Can we be less restrictive for a QCA general purpose chip? Ok. To me, at least the enable gpio seems required. > >> + >> +Example: >> + >> +serial@7570000 { >> + pinctrl-names = "default", "sleep"; >> + pinctrl-0 = <&blsp1_uart1_default>; >> + pinctrl-1 = <&blsp1_uart1_sleep>; >> + >> + bluetooth { >> + compatible = "qcom,qca6174-bt"; >> + >> + enable-gpios = <&pm8994_gpios 19 GPIO_ACTIVE_HIGH>; >> + >> + pinctrl-names = "default"; >> + pinctrl-0 = <&bt_en_pin_a>; > > This one I do not understand and you might want to shed some light into why this is done that way. Sure. It reclaims this gpio pin for this device. Will add it to the documentation. > >> + >> + clocks = <&divclk4>; > > No clock-names? No need for a name as there is only one clk obtained by passing a NULL id to devm_gpiod_get(). Regards, Thierry > > Regards > > Marcel > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, Mar 20, 2018 at 04:23:30AM +0100, Thierry Escande wrote: > Add binding document for serial bluetooth chips using Qualcomm protocol. > > Signed-off-by: Thierry Escande <thierry.escande@linaro.org> > --- > > v5: > - Rename 'bt-disable-n' gpio as 'enable' > > v4: > - Move bt-disable-n-gpios to required properties section > - Add clocks and pinctrl-0 as required properties > > v3: no change > v2: no change > > .../devicetree/bindings/net/qualcomm-bluetooth.txt | 34 ++++++++++++++++++++++ > 1 file changed, 34 insertions(+) > create mode 100644 Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt Reviewed-by: Rob Herring <robh@kernel.org> -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue 20 Mar 23:58 HKT 2018, Marcel Holtmann wrote: > > Signed-off-by: Thierry Escande <thierry.escande@linaro.org> [..] > > + - clocks: clock phandle for SUSCLK_32KHZ > > if I compare this with broadcom-bluetooth.txt or ti-bluetooth.txt then > besides compatible, everything else is optional. The > nokia-bluetooth.txt has everything required, but that is also a really > specific platform. > > Can we be less restrictive for a QCA general purpose chip? > The way we deal with this in other bindings is that we tie such requirements to the compatible; i.e. we would say that qcom,qca6174-bt requires a clock and we would have something like qcom,qca-bt that makes it optional. The beauty of this is that the driver will tell you if you forgot to specify the clock when it actually is required, which saves you considerable amount of debugging time. NB. The way the bcm driver handles this is insufficient, as it treats any error from clk_get as "there's no clock specified". The driver should accept a clock not being specified, but should fail properly when a clock is specified but can't be acquired (e.g. due to clk_get() returning EPROBE_DEFER). > > + > > +Example: > > + > > +serial@7570000 { > > + pinctrl-names = "default", "sleep"; > > + pinctrl-0 = <&blsp1_uart1_default>; > > + pinctrl-1 = <&blsp1_uart1_sleep>; > > + > > + bluetooth { > > + compatible = "qcom,qca6174-bt"; > > + > > + enable-gpios = <&pm8994_gpios 19 GPIO_ACTIVE_HIGH>; > > + > > + pinctrl-names = "default"; > > + pinctrl-0 = <&bt_en_pin_a>; > > This one I do not understand and you might want to shed some light > into why this is done that way. > This is completely generic and only relates to getting the electrical properties of the gpio pin set up correctly. So I would recommend that we omit this from the binding and example (including the pinctrl properties for the serial above). Regards, Bjorn -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Bjorn, On 27/03/2018 00:51, Bjorn Andersson wrote: > On Tue 20 Mar 23:58 HKT 2018, Marcel Holtmann wrote: >>> Signed-off-by: Thierry Escande <thierry.escande@linaro.org> > [..] >>> + - clocks: clock phandle for SUSCLK_32KHZ >> >> if I compare this with broadcom-bluetooth.txt or ti-bluetooth.txt then >> besides compatible, everything else is optional. The >> nokia-bluetooth.txt has everything required, but that is also a really >> specific platform. >> >> Can we be less restrictive for a QCA general purpose chip? >> > > The way we deal with this in other bindings is that we tie such > requirements to the compatible; i.e. we would say that qcom,qca6174-bt > requires a clock and we would have something like qcom,qca-bt that makes > it optional. > > The beauty of this is that the driver will tell you if you forgot to > specify the clock when it actually is required, which saves you > considerable amount of debugging time. > > > NB. The way the bcm driver handles this is insufficient, as it treats > any error from clk_get as "there's no clock specified". The driver > should accept a clock not being specified, but should fail properly when > a clock is specified but can't be acquired (e.g. due to clk_get() > returning EPROBE_DEFER). > >>> + >>> +Example: >>> + >>> +serial@7570000 { >>> + pinctrl-names = "default", "sleep"; >>> + pinctrl-0 = <&blsp1_uart1_default>; >>> + pinctrl-1 = <&blsp1_uart1_sleep>; >>> + >>> + bluetooth { >>> + compatible = "qcom,qca6174-bt"; >>> + >>> + enable-gpios = <&pm8994_gpios 19 GPIO_ACTIVE_HIGH>; >>> + >>> + pinctrl-names = "default"; >>> + pinctrl-0 = <&bt_en_pin_a>; >> >> This one I do not understand and you might want to shed some light >> into why this is done that way. >> > > This is completely generic and only relates to getting the electrical > properties of the gpio pin set up correctly. So I would recommend that > we omit this from the binding and example (including the pinctrl > properties for the serial above). If I remove the pinctrl entry in the bluetooth node, the gpio19 is then marked as unclaimed. The drive strength also defaults to low but that doesn't seem to be an issue and the the chip can still be enabled through gpio19. Is it ok to have it unclaimed? If so I can remove it from the binding and the doc then. Regarding the blsp1_uart1_default of the serial node, I can still enable the chip if I remove it but the hci commands all end in timeout. It seems that the function for these pins has to be explicitly set to blsp_uart2. So at least, the default pinctrl seems mandatory. Regards, Thierry > > Regards, > Bjorn > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue 27 Mar 08:56 PDT 2018, Thierry Escande wrote: > Hi Bjorn, > > On 27/03/2018 00:51, Bjorn Andersson wrote: > > On Tue 20 Mar 23:58 HKT 2018, Marcel Holtmann wrote: > > > > Signed-off-by: Thierry Escande <thierry.escande@linaro.org> > > [..] > > > > + - clocks: clock phandle for SUSCLK_32KHZ > > > > > > if I compare this with broadcom-bluetooth.txt or ti-bluetooth.txt then > > > besides compatible, everything else is optional. The > > > nokia-bluetooth.txt has everything required, but that is also a really > > > specific platform. > > > > > > Can we be less restrictive for a QCA general purpose chip? > > > > > > > The way we deal with this in other bindings is that we tie such > > requirements to the compatible; i.e. we would say that qcom,qca6174-bt > > requires a clock and we would have something like qcom,qca-bt that makes > > it optional. > > > > The beauty of this is that the driver will tell you if you forgot to > > specify the clock when it actually is required, which saves you > > considerable amount of debugging time. > > > > > > NB. The way the bcm driver handles this is insufficient, as it treats > > any error from clk_get as "there's no clock specified". The driver > > should accept a clock not being specified, but should fail properly when > > a clock is specified but can't be acquired (e.g. due to clk_get() > > returning EPROBE_DEFER). > > > > > > + > > > > +Example: > > > > + > > > > +serial@7570000 { > > > > + pinctrl-names = "default", "sleep"; > > > > + pinctrl-0 = <&blsp1_uart1_default>; > > > > + pinctrl-1 = <&blsp1_uart1_sleep>; > > > > + > > > > + bluetooth { > > > > + compatible = "qcom,qca6174-bt"; > > > > + > > > > + enable-gpios = <&pm8994_gpios 19 GPIO_ACTIVE_HIGH>; > > > > + > > > > + pinctrl-names = "default"; > > > > + pinctrl-0 = <&bt_en_pin_a>; > > > > > > This one I do not understand and you might want to shed some light > > > into why this is done that way. > > > > > > > This is completely generic and only relates to getting the electrical > > properties of the gpio pin set up correctly. So I would recommend that > > we omit this from the binding and example (including the pinctrl > > properties for the serial above). > > If I remove the pinctrl entry in the bluetooth node, the gpio19 is then > marked as unclaimed. The drive strength also defaults to low but that > doesn't seem to be an issue and the the chip can still be enabled through > gpio19. Is it ok to have it unclaimed? If so I can remove it from the > binding and the doc then. > > Regarding the blsp1_uart1_default of the serial node, I can still enable the > chip if I remove it but the hci commands all end in timeout. It seems that > the function for these pins has to be explicitly set to blsp_uart2. So at > least, the default pinctrl seems mandatory. > Our board needs these properties to get the uart and gpio in the right state, but this is unrelated to BT - that's why I suggested that you omit these properties from the BT binding. Regards, Bjorn -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt b/Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt new file mode 100644 index 000000000000..bbc2973634b2 --- /dev/null +++ b/Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt @@ -0,0 +1,34 @@ +Qualcomm Bluetooth Chips +--------------------- + +This documents the binding structure and common properties for serial +attached Qualcomm devices. + +Serial attached Qualcomm devices shall be a child node of the host UART +device the slave device is attached to. + +Required properties: + - compatible: should contain one of the following: + * "qcom,qca6174-bt" + - enable-gpios: gpio specifier used to enable chip + - pinctrl-0: pin phandle for bt_en gpio + - clocks: clock phandle for SUSCLK_32KHZ + +Example: + +serial@7570000 { + pinctrl-names = "default", "sleep"; + pinctrl-0 = <&blsp1_uart1_default>; + pinctrl-1 = <&blsp1_uart1_sleep>; + + bluetooth { + compatible = "qcom,qca6174-bt"; + + enable-gpios = <&pm8994_gpios 19 GPIO_ACTIVE_HIGH>; + + pinctrl-names = "default"; + pinctrl-0 = <&bt_en_pin_a>; + + clocks = <&divclk4>; + }; +};
Add binding document for serial bluetooth chips using Qualcomm protocol. Signed-off-by: Thierry Escande <thierry.escande@linaro.org> --- v5: - Rename 'bt-disable-n' gpio as 'enable' v4: - Move bt-disable-n-gpios to required properties section - Add clocks and pinctrl-0 as required properties v3: no change v2: no change .../devicetree/bindings/net/qualcomm-bluetooth.txt | 34 ++++++++++++++++++++++ 1 file changed, 34 insertions(+) create mode 100644 Documentation/devicetree/bindings/net/qualcomm-bluetooth.txt