| Message ID | 20191018052405.3693555-3-bjorn.andersson@linaro.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | f2edd66e515b9944a7e516510a54959e5004181b |
| Headers | show |
| Series | Bluetooth: hci_qca: Regulator usage cleanup | expand |
On 2019-10-18 10:54, Bjorn Andersson wrote: > Devices with specific voltage requirements should not request voltage > from the driver, but instead rely on the system configuration to define > appropriate voltages for each rail. > > This ensures that PMIC and board variations are accounted for, > something > that the 0.1V range in the hci_qca driver currently tries to address. > But on the Lenovo Yoga C630 (with wcn3990) vddch0 is 3.1V, which means > the driver will fail to set the voltage. > > Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> > --- > drivers/bluetooth/hci_qca.c | 26 ++++++++------------------ > 1 file changed, 8 insertions(+), 18 deletions(-) > > diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c > index c07c529b0d81..54aafcc69d06 100644 > --- a/drivers/bluetooth/hci_qca.c > +++ b/drivers/bluetooth/hci_qca.c > @@ -130,8 +130,6 @@ enum qca_speed_type { > */ > struct qca_vreg { > const char *name; > - unsigned int min_uV; > - unsigned int max_uV; > unsigned int load_uA; > }; > > @@ -1332,10 +1330,10 @@ static const struct hci_uart_proto qca_proto = > { > static const struct qca_vreg_data qca_soc_data_wcn3990 = { > .soc_type = QCA_WCN3990, > .vregs = (struct qca_vreg []) { > - { "vddio", 1800000, 1900000, 15000 }, > - { "vddxo", 1800000, 1900000, 80000 }, > - { "vddrf", 1300000, 1350000, 300000 }, > - { "vddch0", 3300000, 3400000, 450000 }, > + { "vddio", 15000 }, > + { "vddxo", 80000 }, > + { "vddrf", 300000 }, > + { "vddch0", 450000 }, > }, > .num_vregs = 4, > }; > @@ -1343,10 +1341,10 @@ static const struct qca_vreg_data > qca_soc_data_wcn3990 = { > static const struct qca_vreg_data qca_soc_data_wcn3998 = { > .soc_type = QCA_WCN3998, > .vregs = (struct qca_vreg []) { > - { "vddio", 1800000, 1900000, 10000 }, > - { "vddxo", 1800000, 1900000, 80000 }, > - { "vddrf", 1300000, 1352000, 300000 }, > - { "vddch0", 3300000, 3300000, 450000 }, > + { "vddio", 10000 }, > + { "vddxo", 80000 }, > + { "vddrf", 300000 }, > + { "vddch0", 450000 }, > }, > .num_vregs = 4, > }; > @@ -1386,13 +1384,6 @@ static int qca_power_off(struct hci_dev *hdev) > static int qca_enable_regulator(struct qca_vreg vregs, > struct regulator *regulator) > { > - int ret; > - > - ret = regulator_set_voltage(regulator, vregs.min_uV, > - vregs.max_uV); > - if (ret) > - return ret; > - > return regulator_enable(regulator); > > } > @@ -1401,7 +1392,6 @@ static void qca_disable_regulator(struct qca_vreg > vregs, > struct regulator *regulator) > { > regulator_disable(regulator); > - regulator_set_voltage(regulator, 0, vregs.max_uV); > > }
On Thu, Oct 17, 2019 at 10:24:02PM -0700, Bjorn Andersson wrote: > Devices with specific voltage requirements should not request voltage > from the driver, but instead rely on the system configuration to define > appropriate voltages for each rail. > > This ensures that PMIC and board variations are accounted for, something > that the 0.1V range in the hci_qca driver currently tries to address. > But on the Lenovo Yoga C630 (with wcn3990) vddch0 is 3.1V, which means > the driver will fail to set the voltage. > > Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> > --- > drivers/bluetooth/hci_qca.c | 26 ++++++++------------------ > 1 file changed, 8 insertions(+), 18 deletions(-) > > diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c > index c07c529b0d81..54aafcc69d06 100644 > --- a/drivers/bluetooth/hci_qca.c > +++ b/drivers/bluetooth/hci_qca.c > @@ -130,8 +130,6 @@ enum qca_speed_type { > */ > struct qca_vreg { > const char *name; > - unsigned int min_uV; > - unsigned int max_uV; > unsigned int load_uA; > }; > > @@ -1332,10 +1330,10 @@ static const struct hci_uart_proto qca_proto = { > static const struct qca_vreg_data qca_soc_data_wcn3990 = { > .soc_type = QCA_WCN3990, > .vregs = (struct qca_vreg []) { > - { "vddio", 1800000, 1900000, 15000 }, > - { "vddxo", 1800000, 1900000, 80000 }, > - { "vddrf", 1300000, 1350000, 300000 }, > - { "vddch0", 3300000, 3400000, 450000 }, > + { "vddio", 15000 }, > + { "vddxo", 80000 }, > + { "vddrf", 300000 }, > + { "vddch0", 450000 }, > }, > .num_vregs = 4, > }; > @@ -1343,10 +1341,10 @@ static const struct qca_vreg_data qca_soc_data_wcn3990 = { > static const struct qca_vreg_data qca_soc_data_wcn3998 = { > .soc_type = QCA_WCN3998, > .vregs = (struct qca_vreg []) { > - { "vddio", 1800000, 1900000, 10000 }, > - { "vddxo", 1800000, 1900000, 80000 }, > - { "vddrf", 1300000, 1352000, 300000 }, > - { "vddch0", 3300000, 3300000, 450000 }, > + { "vddio", 10000 }, > + { "vddxo", 80000 }, > + { "vddrf", 300000 }, > + { "vddch0", 450000 }, > }, > .num_vregs = 4, > }; > @@ -1386,13 +1384,6 @@ static int qca_power_off(struct hci_dev *hdev) > static int qca_enable_regulator(struct qca_vreg vregs, > struct regulator *regulator) > { > - int ret; > - > - ret = regulator_set_voltage(regulator, vregs.min_uV, > - vregs.max_uV); > - if (ret) > - return ret; > - > return regulator_enable(regulator); > > } > @@ -1401,7 +1392,6 @@ static void qca_disable_regulator(struct qca_vreg vregs, > struct regulator *regulator) > { > regulator_disable(regulator); > - regulator_set_voltage(regulator, 0, vregs.max_uV); > > } This was brought up multiple times during the initial review, but wasn't addressed. Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
+ Bala On 2019-10-18 23:52, Matthias Kaehlcke wrote: > On Thu, Oct 17, 2019 at 10:24:02PM -0700, Bjorn Andersson wrote: >> Devices with specific voltage requirements should not request voltage >> from the driver, but instead rely on the system configuration to >> define >> appropriate voltages for each rail. >> >> This ensures that PMIC and board variations are accounted for, >> something >> that the 0.1V range in the hci_qca driver currently tries to address. >> But on the Lenovo Yoga C630 (with wcn3990) vddch0 is 3.1V, which means >> the driver will fail to set the voltage. >> >> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> >> --- >> drivers/bluetooth/hci_qca.c | 26 ++++++++------------------ >> 1 file changed, 8 insertions(+), 18 deletions(-) >> >> diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c >> index c07c529b0d81..54aafcc69d06 100644 >> --- a/drivers/bluetooth/hci_qca.c >> +++ b/drivers/bluetooth/hci_qca.c >> @@ -130,8 +130,6 @@ enum qca_speed_type { >> */ >> struct qca_vreg { >> const char *name; >> - unsigned int min_uV; >> - unsigned int max_uV; >> unsigned int load_uA; >> }; >> >> @@ -1332,10 +1330,10 @@ static const struct hci_uart_proto qca_proto = >> { >> static const struct qca_vreg_data qca_soc_data_wcn3990 = { >> .soc_type = QCA_WCN3990, >> .vregs = (struct qca_vreg []) { >> - { "vddio", 1800000, 1900000, 15000 }, >> - { "vddxo", 1800000, 1900000, 80000 }, >> - { "vddrf", 1300000, 1350000, 300000 }, >> - { "vddch0", 3300000, 3400000, 450000 }, >> + { "vddio", 15000 }, >> + { "vddxo", 80000 }, >> + { "vddrf", 300000 }, >> + { "vddch0", 450000 }, >> }, >> .num_vregs = 4, >> }; >> @@ -1343,10 +1341,10 @@ static const struct qca_vreg_data >> qca_soc_data_wcn3990 = { >> static const struct qca_vreg_data qca_soc_data_wcn3998 = { >> .soc_type = QCA_WCN3998, >> .vregs = (struct qca_vreg []) { >> - { "vddio", 1800000, 1900000, 10000 }, >> - { "vddxo", 1800000, 1900000, 80000 }, >> - { "vddrf", 1300000, 1352000, 300000 }, >> - { "vddch0", 3300000, 3300000, 450000 }, >> + { "vddio", 10000 }, >> + { "vddxo", 80000 }, >> + { "vddrf", 300000 }, >> + { "vddch0", 450000 }, >> }, >> .num_vregs = 4, >> }; >> @@ -1386,13 +1384,6 @@ static int qca_power_off(struct hci_dev *hdev) >> static int qca_enable_regulator(struct qca_vreg vregs, >> struct regulator *regulator) >> { >> - int ret; >> - >> - ret = regulator_set_voltage(regulator, vregs.min_uV, >> - vregs.max_uV); >> - if (ret) >> - return ret; >> - >> return regulator_enable(regulator); >> >> } >> @@ -1401,7 +1392,6 @@ static void qca_disable_regulator(struct >> qca_vreg vregs, >> struct regulator *regulator) >> { >> regulator_disable(regulator); >> - regulator_set_voltage(regulator, 0, vregs.max_uV); >> >> } > > This was brought up multiple times during the initial review, but > wasn't addressed. > > Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Hi Matthias, Bjorn andresson, On 2019-10-21 12:07, Harish Bandi wrote: > + Bala > > On 2019-10-18 23:52, Matthias Kaehlcke wrote: >> On Thu, Oct 17, 2019 at 10:24:02PM -0700, Bjorn Andersson wrote: >>> Devices with specific voltage requirements should not request voltage >>> from the driver, but instead rely on the system configuration to >>> define >>> appropriate voltages for each rail. >>> >>> This ensures that PMIC and board variations are accounted for, >>> something >>> that the 0.1V range in the hci_qca driver currently tries to address. >>> But on the Lenovo Yoga C630 (with wcn3990) vddch0 is 3.1V, which >>> means >>> the driver will fail to set the voltage. >>> >>> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> >>> --- >>> drivers/bluetooth/hci_qca.c | 26 ++++++++------------------ >>> 1 file changed, 8 insertions(+), 18 deletions(-) >>> >>> diff --git a/drivers/bluetooth/hci_qca.c >>> b/drivers/bluetooth/hci_qca.c >>> index c07c529b0d81..54aafcc69d06 100644 >>> --- a/drivers/bluetooth/hci_qca.c >>> +++ b/drivers/bluetooth/hci_qca.c >>> @@ -130,8 +130,6 @@ enum qca_speed_type { >>> */ >>> struct qca_vreg { >>> const char *name; >>> - unsigned int min_uV; >>> - unsigned int max_uV; >>> unsigned int load_uA; >>> }; >>> >>> @@ -1332,10 +1330,10 @@ static const struct hci_uart_proto qca_proto >>> = { >>> static const struct qca_vreg_data qca_soc_data_wcn3990 = { >>> .soc_type = QCA_WCN3990, >>> .vregs = (struct qca_vreg []) { >>> - { "vddio", 1800000, 1900000, 15000 }, >>> - { "vddxo", 1800000, 1900000, 80000 }, >>> - { "vddrf", 1300000, 1350000, 300000 }, >>> - { "vddch0", 3300000, 3400000, 450000 }, >>> + { "vddio", 15000 }, >>> + { "vddxo", 80000 }, >>> + { "vddrf", 300000 }, >>> + { "vddch0", 450000 }, >>> }, >>> .num_vregs = 4, >>> }; >>> @@ -1343,10 +1341,10 @@ static const struct qca_vreg_data >>> qca_soc_data_wcn3990 = { >>> static const struct qca_vreg_data qca_soc_data_wcn3998 = { >>> .soc_type = QCA_WCN3998, >>> .vregs = (struct qca_vreg []) { >>> - { "vddio", 1800000, 1900000, 10000 }, >>> - { "vddxo", 1800000, 1900000, 80000 }, >>> - { "vddrf", 1300000, 1352000, 300000 }, >>> - { "vddch0", 3300000, 3300000, 450000 }, >>> + { "vddio", 10000 }, >>> + { "vddxo", 80000 }, >>> + { "vddrf", 300000 }, >>> + { "vddch0", 450000 }, >>> }, >>> .num_vregs = 4, >>> }; >>> @@ -1386,13 +1384,6 @@ static int qca_power_off(struct hci_dev *hdev) >>> static int qca_enable_regulator(struct qca_vreg vregs, >>> struct regulator *regulator) >>> { >>> - int ret; >>> - >>> - ret = regulator_set_voltage(regulator, vregs.min_uV, >>> - vregs.max_uV); >>> - if (ret) >>> - return ret; >>> - >>> return regulator_enable(regulator); >>> >>> } >>> @@ -1401,7 +1392,6 @@ static void qca_disable_regulator(struct >>> qca_vreg vregs, >>> struct regulator *regulator) >>> { >>> regulator_disable(regulator); >>> - regulator_set_voltage(regulator, 0, vregs.max_uV); >>> >>> } >> >> This was brought up multiple times during the initial review, but >> wasn't addressed. >> >> Reviewed-by: Matthias Kaehlcke <mka@chromium.org> yes true PMIC dts regulator should do this. But we have some real time issues observed. Issue 1: In PMIC dts node, ASAIK we have three levels of voltages. 1. Default voltage. 2. Minimum voltage. (mandatory entry) 3. Maximum voltage. (mandatory entry) Let us assume that the if PMIC regulator dts node supports defaults voltage to 3.2 Volts and Min as 3.1 V and max as 3.3V So default operating voltage is 3.1V when we turn on BT (but according to spec SoC requires min of 3.3V to operate, Might have some functionality failures on end to end testing Issue 2: WCN3990 RF is shared with WiFi, so it also try to turn on the regulators. Wifi driver uses the same approach of restricting to min and max voltages in driver. Let us assume we turned ON BT and CH0 is set to 3.1v (as in your case), Wifi is tuned on now, as its request the CH0 to operate at 3.3 Volts, regulator will fail to set this voltage as BT is operating at CH0 3.1v (assuming max voltage is 3.2v) https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git/tree/drivers/net/wireless/ath/ath10k/snoc.c#n39 Issue 3: By mistake PMIC has low min or default voltage and high max voltages, that is harm for WNC3990. I would suggest to restrict the min and max voltages in driver, instead of relaying on PMIC to do this. BTW pmic will do this and doing it in our driver is safer. Let me know your views on this.
On Tue, Oct 22, 2019 at 11:35:43AM +0530, Balakrishna Godavarthi wrote: > Hi Matthias, Bjorn andresson, > > On 2019-10-21 12:07, Harish Bandi wrote: > > + Bala > > > > On 2019-10-18 23:52, Matthias Kaehlcke wrote: > > > On Thu, Oct 17, 2019 at 10:24:02PM -0700, Bjorn Andersson wrote: > > > > Devices with specific voltage requirements should not request voltage > > > > from the driver, but instead rely on the system configuration to > > > > define > > > > appropriate voltages for each rail. > > > > > > > > This ensures that PMIC and board variations are accounted for, > > > > something > > > > that the 0.1V range in the hci_qca driver currently tries to address. > > > > But on the Lenovo Yoga C630 (with wcn3990) vddch0 is 3.1V, which > > > > means > > > > the driver will fail to set the voltage. > > > > > > > > Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> > > > > --- > > > > drivers/bluetooth/hci_qca.c | 26 ++++++++------------------ > > > > 1 file changed, 8 insertions(+), 18 deletions(-) > > > > > > > > diff --git a/drivers/bluetooth/hci_qca.c > > > > b/drivers/bluetooth/hci_qca.c > > > > index c07c529b0d81..54aafcc69d06 100644 > > > > --- a/drivers/bluetooth/hci_qca.c > > > > +++ b/drivers/bluetooth/hci_qca.c > > > > @@ -130,8 +130,6 @@ enum qca_speed_type { > > > > */ > > > > struct qca_vreg { > > > > const char *name; > > > > - unsigned int min_uV; > > > > - unsigned int max_uV; > > > > unsigned int load_uA; > > > > }; > > > > > > > > @@ -1332,10 +1330,10 @@ static const struct hci_uart_proto > > > > qca_proto = { > > > > static const struct qca_vreg_data qca_soc_data_wcn3990 = { > > > > .soc_type = QCA_WCN3990, > > > > .vregs = (struct qca_vreg []) { > > > > - { "vddio", 1800000, 1900000, 15000 }, > > > > - { "vddxo", 1800000, 1900000, 80000 }, > > > > - { "vddrf", 1300000, 1350000, 300000 }, > > > > - { "vddch0", 3300000, 3400000, 450000 }, > > > > + { "vddio", 15000 }, > > > > + { "vddxo", 80000 }, > > > > + { "vddrf", 300000 }, > > > > + { "vddch0", 450000 }, > > > > }, > > > > .num_vregs = 4, > > > > }; > > > > @@ -1343,10 +1341,10 @@ static const struct qca_vreg_data > > > > qca_soc_data_wcn3990 = { > > > > static const struct qca_vreg_data qca_soc_data_wcn3998 = { > > > > .soc_type = QCA_WCN3998, > > > > .vregs = (struct qca_vreg []) { > > > > - { "vddio", 1800000, 1900000, 10000 }, > > > > - { "vddxo", 1800000, 1900000, 80000 }, > > > > - { "vddrf", 1300000, 1352000, 300000 }, > > > > - { "vddch0", 3300000, 3300000, 450000 }, > > > > + { "vddio", 10000 }, > > > > + { "vddxo", 80000 }, > > > > + { "vddrf", 300000 }, > > > > + { "vddch0", 450000 }, > > > > }, > > > > .num_vregs = 4, > > > > }; > > > > @@ -1386,13 +1384,6 @@ static int qca_power_off(struct hci_dev *hdev) > > > > static int qca_enable_regulator(struct qca_vreg vregs, > > > > struct regulator *regulator) > > > > { > > > > - int ret; > > > > - > > > > - ret = regulator_set_voltage(regulator, vregs.min_uV, > > > > - vregs.max_uV); > > > > - if (ret) > > > > - return ret; > > > > - > > > > return regulator_enable(regulator); > > > > > > > > } > > > > @@ -1401,7 +1392,6 @@ static void qca_disable_regulator(struct > > > > qca_vreg vregs, > > > > struct regulator *regulator) > > > > { > > > > regulator_disable(regulator); > > > > - regulator_set_voltage(regulator, 0, vregs.max_uV); > > > > > > > > } > > > > > > This was brought up multiple times during the initial review, but > > > wasn't addressed. > > > > > > Reviewed-by: Matthias Kaehlcke <mka@chromium.org> > > > yes true PMIC dts regulator should do this. > But we have some real time issues observed. > > Issue 1: > > In PMIC dts node, ASAIK we have three levels of voltages. > > 1. Default voltage. > 2. Minimum voltage. (mandatory entry) > 3. Maximum voltage. (mandatory entry) > > Let us assume that the if PMIC regulator dts node supports defaults voltage > to 3.2 Volts and Min as 3.1 V and max as 3.3V > So default operating voltage is 3.1V when we turn on BT (but according to > spec SoC requires min of 3.3V to operate, > Might have some functionality failures on end to end testing The PMIC regulator shouldn't be configured with the entire range of voltages it can generate, but with a range of voltages that is suitable for all its consumers. In other words if BT requires a minimum voltage of 3.3V the minimum voltage of the regulator should be at least 3.3V. > Issue 2: > > WCN3990 RF is shared with WiFi, so it also try to turn on the regulators. > Wifi driver uses the same approach of restricting to min and max voltages in > driver. > Let us assume we turned ON BT and CH0 is set to 3.1v (as in your case), Wifi > is tuned on now, as its request the CH0 to operate at 3.3 Volts, regulator > will fail to set this voltage as BT is operating > at CH0 3.1v (assuming max voltage is 3.2v) > https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git/tree/drivers/net/wireless/ath/ath10k/snoc.c#n39 see above > Issue 3: > > By mistake PMIC has low min or default voltage and high max voltages, that > is harm for WNC3990. > > I would suggest to restrict the min and max voltages in driver, instead of > relaying on PMIC to do this. > BTW pmic will do this and doing it in our driver is safer. What if another device switches the regulator on before BT? Again, what you describe is a misconfiguration of the regulator and should be fixed at its root, instead of implementing unreliable 'safeguards' in each and every driver using regulators.
Hi Matthias, On 2019-10-22 22:45, Matthias Kaehlcke wrote: > On Tue, Oct 22, 2019 at 11:35:43AM +0530, Balakrishna Godavarthi wrote: >> Hi Matthias, Bjorn andresson, >> >> On 2019-10-21 12:07, Harish Bandi wrote: >> > + Bala >> > >> > On 2019-10-18 23:52, Matthias Kaehlcke wrote: >> > > On Thu, Oct 17, 2019 at 10:24:02PM -0700, Bjorn Andersson wrote: >> > > > Devices with specific voltage requirements should not request voltage >> > > > from the driver, but instead rely on the system configuration to >> > > > define >> > > > appropriate voltages for each rail. >> > > > >> > > > This ensures that PMIC and board variations are accounted for, >> > > > something >> > > > that the 0.1V range in the hci_qca driver currently tries to address. >> > > > But on the Lenovo Yoga C630 (with wcn3990) vddch0 is 3.1V, which >> > > > means >> > > > the driver will fail to set the voltage. >> > > > >> > > > Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> >> > > > --- >> > > > drivers/bluetooth/hci_qca.c | 26 ++++++++------------------ >> > > > 1 file changed, 8 insertions(+), 18 deletions(-) >> > > > >> > > > diff --git a/drivers/bluetooth/hci_qca.c >> > > > b/drivers/bluetooth/hci_qca.c >> > > > index c07c529b0d81..54aafcc69d06 100644 >> > > > --- a/drivers/bluetooth/hci_qca.c >> > > > +++ b/drivers/bluetooth/hci_qca.c >> > > > @@ -130,8 +130,6 @@ enum qca_speed_type { >> > > > */ >> > > > struct qca_vreg { >> > > > const char *name; >> > > > - unsigned int min_uV; >> > > > - unsigned int max_uV; >> > > > unsigned int load_uA; >> > > > }; >> > > > >> > > > @@ -1332,10 +1330,10 @@ static const struct hci_uart_proto >> > > > qca_proto = { >> > > > static const struct qca_vreg_data qca_soc_data_wcn3990 = { >> > > > .soc_type = QCA_WCN3990, >> > > > .vregs = (struct qca_vreg []) { >> > > > - { "vddio", 1800000, 1900000, 15000 }, >> > > > - { "vddxo", 1800000, 1900000, 80000 }, >> > > > - { "vddrf", 1300000, 1350000, 300000 }, >> > > > - { "vddch0", 3300000, 3400000, 450000 }, >> > > > + { "vddio", 15000 }, >> > > > + { "vddxo", 80000 }, >> > > > + { "vddrf", 300000 }, >> > > > + { "vddch0", 450000 }, >> > > > }, >> > > > .num_vregs = 4, >> > > > }; >> > > > @@ -1343,10 +1341,10 @@ static const struct qca_vreg_data >> > > > qca_soc_data_wcn3990 = { >> > > > static const struct qca_vreg_data qca_soc_data_wcn3998 = { >> > > > .soc_type = QCA_WCN3998, >> > > > .vregs = (struct qca_vreg []) { >> > > > - { "vddio", 1800000, 1900000, 10000 }, >> > > > - { "vddxo", 1800000, 1900000, 80000 }, >> > > > - { "vddrf", 1300000, 1352000, 300000 }, >> > > > - { "vddch0", 3300000, 3300000, 450000 }, >> > > > + { "vddio", 10000 }, >> > > > + { "vddxo", 80000 }, >> > > > + { "vddrf", 300000 }, >> > > > + { "vddch0", 450000 }, >> > > > }, >> > > > .num_vregs = 4, >> > > > }; >> > > > @@ -1386,13 +1384,6 @@ static int qca_power_off(struct hci_dev *hdev) >> > > > static int qca_enable_regulator(struct qca_vreg vregs, >> > > > struct regulator *regulator) >> > > > { >> > > > - int ret; >> > > > - >> > > > - ret = regulator_set_voltage(regulator, vregs.min_uV, >> > > > - vregs.max_uV); >> > > > - if (ret) >> > > > - return ret; >> > > > - >> > > > return regulator_enable(regulator); >> > > > >> > > > } >> > > > @@ -1401,7 +1392,6 @@ static void qca_disable_regulator(struct >> > > > qca_vreg vregs, >> > > > struct regulator *regulator) >> > > > { >> > > > regulator_disable(regulator); >> > > > - regulator_set_voltage(regulator, 0, vregs.max_uV); >> > > > >> > > > } >> > > >> > > This was brought up multiple times during the initial review, but >> > > wasn't addressed. >> > > >> > > Reviewed-by: Matthias Kaehlcke <mka@chromium.org> >> >> >> yes true PMIC dts regulator should do this. >> But we have some real time issues observed. >> >> Issue 1: >> >> In PMIC dts node, ASAIK we have three levels of voltages. >> >> 1. Default voltage. >> 2. Minimum voltage. (mandatory entry) >> 3. Maximum voltage. (mandatory entry) >> >> Let us assume that the if PMIC regulator dts node supports defaults >> voltage >> to 3.2 Volts and Min as 3.1 V and max as 3.3V >> So default operating voltage is 3.1V when we turn on BT (but >> according to >> spec SoC requires min of 3.3V to operate, >> Might have some functionality failures on end to end testing > > The PMIC regulator shouldn't be configured with the entire range of > voltages > it can generate, but with a range of voltages that is suitable for all > its > consumers. > > In other words if BT requires a minimum voltage of 3.3V the minimum > voltage > of the regulator should be at least 3.3V. > >> Issue 2: >> >> WCN3990 RF is shared with WiFi, so it also try to turn on the >> regulators. >> Wifi driver uses the same approach of restricting to min and max >> voltages in >> driver. >> Let us assume we turned ON BT and CH0 is set to 3.1v (as in your >> case), Wifi >> is tuned on now, as its request the CH0 to operate at 3.3 Volts, >> regulator >> will fail to set this voltage as BT is operating >> at CH0 3.1v (assuming max voltage is 3.2v) >> https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git/tree/drivers/net/wireless/ath/ath10k/snoc.c#n39 > > see above > >> Issue 3: >> >> By mistake PMIC has low min or default voltage and high max voltages, >> that >> is harm for WNC3990. >> >> I would suggest to restrict the min and max voltages in driver, >> instead of >> relaying on PMIC to do this. >> BTW pmic will do this and doing it in our driver is safer. > > What if another device switches the regulator on before BT? > > Again, what you describe is a misconfiguration of the regulator and > should > be fixed at its root, instead of implementing unreliable 'safeguards' > in each > and every driver using regulators. Thanks for detail analysis :)
diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c index c07c529b0d81..54aafcc69d06 100644 --- a/drivers/bluetooth/hci_qca.c +++ b/drivers/bluetooth/hci_qca.c @@ -130,8 +130,6 @@ enum qca_speed_type { */ struct qca_vreg { const char *name; - unsigned int min_uV; - unsigned int max_uV; unsigned int load_uA; }; @@ -1332,10 +1330,10 @@ static const struct hci_uart_proto qca_proto = { static const struct qca_vreg_data qca_soc_data_wcn3990 = { .soc_type = QCA_WCN3990, .vregs = (struct qca_vreg []) { - { "vddio", 1800000, 1900000, 15000 }, - { "vddxo", 1800000, 1900000, 80000 }, - { "vddrf", 1300000, 1350000, 300000 }, - { "vddch0", 3300000, 3400000, 450000 }, + { "vddio", 15000 }, + { "vddxo", 80000 }, + { "vddrf", 300000 }, + { "vddch0", 450000 }, }, .num_vregs = 4, }; @@ -1343,10 +1341,10 @@ static const struct qca_vreg_data qca_soc_data_wcn3990 = { static const struct qca_vreg_data qca_soc_data_wcn3998 = { .soc_type = QCA_WCN3998, .vregs = (struct qca_vreg []) { - { "vddio", 1800000, 1900000, 10000 }, - { "vddxo", 1800000, 1900000, 80000 }, - { "vddrf", 1300000, 1352000, 300000 }, - { "vddch0", 3300000, 3300000, 450000 }, + { "vddio", 10000 }, + { "vddxo", 80000 }, + { "vddrf", 300000 }, + { "vddch0", 450000 }, }, .num_vregs = 4, }; @@ -1386,13 +1384,6 @@ static int qca_power_off(struct hci_dev *hdev) static int qca_enable_regulator(struct qca_vreg vregs, struct regulator *regulator) { - int ret; - - ret = regulator_set_voltage(regulator, vregs.min_uV, - vregs.max_uV); - if (ret) - return ret; - return regulator_enable(regulator); } @@ -1401,7 +1392,6 @@ static void qca_disable_regulator(struct qca_vreg vregs, struct regulator *regulator) { regulator_disable(regulator); - regulator_set_voltage(regulator, 0, vregs.max_uV); }
Devices with specific voltage requirements should not request voltage from the driver, but instead rely on the system configuration to define appropriate voltages for each rail. This ensures that PMIC and board variations are accounted for, something that the 0.1V range in the hci_qca driver currently tries to address. But on the Lenovo Yoga C630 (with wcn3990) vddch0 is 3.1V, which means the driver will fail to set the voltage. Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> --- drivers/bluetooth/hci_qca.c | 26 ++++++++------------------ 1 file changed, 8 insertions(+), 18 deletions(-)