* [PATCH] Fix incomplete initialization of ADC[3:6]$ @ 2015-07-20 18:14 Adam YH Lee 2015-07-20 18:14 ` [PATCH] [TWL4030 MADC] Fix ADC[3:6] readings Adam YH Lee 0 siblings, 1 reply; 10+ messages in thread From: Adam YH Lee @ 2015-07-20 18:14 UTC (permalink / raw) To: linux-arm-kernel Additionally the original discussion for this patch can be found here [5]. $ [1] http://comments.gmane.org/gmane.linux.ports.arm.omap/83698$ [2] http://gumstix.8.x6.nabble.com/twl4030-madc-low-read-value-td4967139.html#none$ [3] https://e2e.ti.com/support/power_management/pmu/f/43/t/732$ [4] http://www.droid-developers.org/images/2/21/Tps65950_TRM.pdf$ [5] http://www.spinics.net/lists/linux-omap/msg120300.html Adam YH Lee (1): [TWL4030 MADC] Fix ADC[3:6] readings drivers/iio/adc/twl4030-madc.c | 14 ++++++++++++++ drivers/phy/phy-twl4030-usb.c | 7 +++++++ 2 files changed, 21 insertions(+) -- 2.1.4 ^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH] [TWL4030 MADC] Fix ADC[3:6] readings 2015-07-20 18:14 [PATCH] Fix incomplete initialization of ADC[3:6]$ Adam YH Lee @ 2015-07-20 18:14 ` Adam YH Lee 2015-07-20 18:54 ` Peter Meerwald 0 siblings, 1 reply; 10+ messages in thread From: Adam YH Lee @ 2015-07-20 18:14 UTC (permalink / raw) To: linux-arm-kernel MADC[3:6] reads incorrect values without these two following changes: - enable the 3v1 bias regulator for ADC[3:6] - configure ADC[3:6] lines as input, not as USB Signed-off-by: Adam YH Lee <adam.yh.lee@gmail.com> --- drivers/iio/adc/twl4030-madc.c | 14 ++++++++++++++ drivers/phy/phy-twl4030-usb.c | 7 +++++++ 2 files changed, 21 insertions(+) diff --git a/drivers/iio/adc/twl4030-madc.c b/drivers/iio/adc/twl4030-madc.c index 94c5f05..b5020ab 100644 --- a/drivers/iio/adc/twl4030-madc.c +++ b/drivers/iio/adc/twl4030-madc.c @@ -45,6 +45,7 @@ #include <linux/types.h> #include <linux/gfp.h> #include <linux/err.h> +#include <linux/regulator/consumer.h> #include <linux/iio/iio.h> @@ -52,6 +53,7 @@ * struct twl4030_madc_data - a container for madc info * @dev: Pointer to device structure for madc * @lock: Mutex protecting this data structure + * @regulator: Pointer to bias regulator for madc * @requests: Array of request struct corresponding to SW1, SW2 and RT * @use_second_irq: IRQ selection (main or co-processor) * @imr: Interrupt mask register of MADC @@ -60,6 +62,7 @@ struct twl4030_madc_data { struct device *dev; struct mutex lock; /* mutex protecting this data structure */ + struct regulator *usb3v1; struct twl4030_madc_request requests[TWL4030_MADC_NUM_METHODS]; bool use_second_irq; u8 imr; @@ -848,6 +851,14 @@ static int twl4030_madc_probe(struct platform_device *pdev) goto err_i2c; } + madc->usb3v1 = devm_regulator_get(madc->dev, "vusb3v1"); + if (IS_ERR(madc->usb3v1)) + return -ENODEV; + + ret = regulator_enable(madc->usb3v1); + if (ret) + dev_err(madc->dev, "could not be enable 3v1 bias regulator\n"); + return 0; err_i2c: @@ -867,6 +878,9 @@ static int twl4030_madc_remove(struct platform_device *pdev) twl4030_madc_set_current_generator(madc, 0, 0); twl4030_madc_set_power(madc, 0); + regulator_disable(madc->usb3v1); + regulator_put(madc->usb3v1); + return 0; } diff --git a/drivers/phy/phy-twl4030-usb.c b/drivers/phy/phy-twl4030-usb.c index 7b04bef..88fc7d7 100644 --- a/drivers/phy/phy-twl4030-usb.c +++ b/drivers/phy/phy-twl4030-usb.c @@ -144,6 +144,9 @@ #define PMBR1 0x0D #define GPIO_USB_4PIN_ULPI_2430C (3 << 0) +#define TWL4030_USB_SEL_MADC_MCPC (1<<3) +#define TWL4030_USB_CARKIT_ANA_CTRL 0xBB + struct twl4030_usb { struct usb_phy phy; struct device *dev; @@ -459,6 +462,10 @@ static int twl4030_phy_power_on(struct phy *phy) twl4030_i2c_access(twl, 0); schedule_delayed_work(&twl->id_workaround_work, 0); + twl4030_usb_write(twl, TWL4030_USB_CARKIT_ANA_CTRL, + twl4030_usb_read(twl, TWL4030_USB_CARKIT_ANA_CTRL) | + TWL4030_USB_SEL_MADC_MCPC); + return 0; } -- 2.1.4 ^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH] [TWL4030 MADC] Fix ADC[3:6] readings 2015-07-20 18:14 ` [PATCH] [TWL4030 MADC] Fix ADC[3:6] readings Adam YH Lee @ 2015-07-20 18:54 ` Peter Meerwald 2015-07-20 19:19 ` Adam Lee 0 siblings, 1 reply; 10+ messages in thread From: Peter Meerwald @ 2015-07-20 18:54 UTC (permalink / raw) To: linux-arm-kernel On Mon, 20 Jul 2015, Adam YH Lee wrote: > MADC[3:6] reads incorrect values without these two following changes: > > - enable the 3v1 bias regulator for ADC[3:6] > - configure ADC[3:6] lines as input, not as USB comments below > Signed-off-by: Adam YH Lee <adam.yh.lee@gmail.com> > --- > drivers/iio/adc/twl4030-madc.c | 14 ++++++++++++++ > drivers/phy/phy-twl4030-usb.c | 7 +++++++ > 2 files changed, 21 insertions(+) > > diff --git a/drivers/iio/adc/twl4030-madc.c b/drivers/iio/adc/twl4030-madc.c > index 94c5f05..b5020ab 100644 > --- a/drivers/iio/adc/twl4030-madc.c > +++ b/drivers/iio/adc/twl4030-madc.c > @@ -45,6 +45,7 @@ > #include <linux/types.h> > #include <linux/gfp.h> > #include <linux/err.h> > +#include <linux/regulator/consumer.h> > > #include <linux/iio/iio.h> > > @@ -52,6 +53,7 @@ > * struct twl4030_madc_data - a container for madc info > * @dev: Pointer to device structure for madc > * @lock: Mutex protecting this data structure > + * @regulator: Pointer to bias regulator for madc > * @requests: Array of request struct corresponding to SW1, SW2 and RT > * @use_second_irq: IRQ selection (main or co-processor) > * @imr: Interrupt mask register of MADC > @@ -60,6 +62,7 @@ > struct twl4030_madc_data { > struct device *dev; > struct mutex lock; /* mutex protecting this data structure */ > + struct regulator *usb3v1; > struct twl4030_madc_request requests[TWL4030_MADC_NUM_METHODS]; > bool use_second_irq; > u8 imr; > @@ -848,6 +851,14 @@ static int twl4030_madc_probe(struct platform_device *pdev) > goto err_i2c; > } > > + madc->usb3v1 = devm_regulator_get(madc->dev, "vusb3v1"); > + if (IS_ERR(madc->usb3v1)) > + return -ENODEV; > + > + ret = regulator_enable(madc->usb3v1); > + if (ret) > + dev_err(madc->dev, "could not be enable 3v1 bias regulator\n"); please fix wording, "could not enable usb 3v1 bias regulator" probably > + > return 0; > > err_i2c: > @@ -867,6 +878,9 @@ static int twl4030_madc_remove(struct platform_device *pdev) > twl4030_madc_set_current_generator(madc, 0, 0); > twl4030_madc_set_power(madc, 0); > > + regulator_disable(madc->usb3v1); > + regulator_put(madc->usb3v1); > + > return 0; > } > > diff --git a/drivers/phy/phy-twl4030-usb.c b/drivers/phy/phy-twl4030-usb.c > index 7b04bef..88fc7d7 100644 > --- a/drivers/phy/phy-twl4030-usb.c > +++ b/drivers/phy/phy-twl4030-usb.c > @@ -144,6 +144,9 @@ > #define PMBR1 0x0D > #define GPIO_USB_4PIN_ULPI_2430C (3 << 0) > > +#define TWL4030_USB_SEL_MADC_MCPC (1<<3) > +#define TWL4030_USB_CARKIT_ANA_CTRL 0xBB > + > struct twl4030_usb { > struct usb_phy phy; > struct device *dev; > @@ -459,6 +462,10 @@ static int twl4030_phy_power_on(struct phy *phy) > twl4030_i2c_access(twl, 0); > schedule_delayed_work(&twl->id_workaround_work, 0); > > + twl4030_usb_write(twl, TWL4030_USB_CARKIT_ANA_CTRL, > + twl4030_usb_read(twl, TWL4030_USB_CARKIT_ANA_CTRL) | > + TWL4030_USB_SEL_MADC_MCPC); > + shouldn't this be done is the adc driver? > return 0; > } > > -- Peter Meerwald +43-664-2444418 (mobile) ^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH] [TWL4030 MADC] Fix ADC[3:6] readings 2015-07-20 18:54 ` Peter Meerwald @ 2015-07-20 19:19 ` Adam Lee 0 siblings, 0 replies; 10+ messages in thread From: Adam Lee @ 2015-07-20 19:19 UTC (permalink / raw) To: linux-arm-kernel Hi Peter, I sent a V2 with corrected wording. My bad! And yes I agree that register setting should be done in the ADC driver. Let me see what I can do, and will report back. Thanks, Adam On Mon, Jul 20, 2015 at 11:54 AM, Peter Meerwald <pmeerw@pmeerw.net> wrote: > On Mon, 20 Jul 2015, Adam YH Lee wrote: > >> MADC[3:6] reads incorrect values without these two following changes: >> >> - enable the 3v1 bias regulator for ADC[3:6] >> - configure ADC[3:6] lines as input, not as USB > > comments below > >> Signed-off-by: Adam YH Lee <adam.yh.lee@gmail.com> >> --- >> drivers/iio/adc/twl4030-madc.c | 14 ++++++++++++++ >> drivers/phy/phy-twl4030-usb.c | 7 +++++++ >> 2 files changed, 21 insertions(+) >> >> diff --git a/drivers/iio/adc/twl4030-madc.c b/drivers/iio/adc/twl4030-madc.c >> index 94c5f05..b5020ab 100644 >> --- a/drivers/iio/adc/twl4030-madc.c >> +++ b/drivers/iio/adc/twl4030-madc.c >> @@ -45,6 +45,7 @@ >> #include <linux/types.h> >> #include <linux/gfp.h> >> #include <linux/err.h> >> +#include <linux/regulator/consumer.h> >> >> #include <linux/iio/iio.h> >> >> @@ -52,6 +53,7 @@ >> * struct twl4030_madc_data - a container for madc info >> * @dev: Pointer to device structure for madc >> * @lock: Mutex protecting this data structure >> + * @regulator: Pointer to bias regulator for madc >> * @requests: Array of request struct corresponding to SW1, SW2 and RT >> * @use_second_irq: IRQ selection (main or co-processor) >> * @imr: Interrupt mask register of MADC >> @@ -60,6 +62,7 @@ >> struct twl4030_madc_data { >> struct device *dev; >> struct mutex lock; /* mutex protecting this data structure */ >> + struct regulator *usb3v1; >> struct twl4030_madc_request requests[TWL4030_MADC_NUM_METHODS]; >> bool use_second_irq; >> u8 imr; >> @@ -848,6 +851,14 @@ static int twl4030_madc_probe(struct platform_device *pdev) >> goto err_i2c; >> } >> >> + madc->usb3v1 = devm_regulator_get(madc->dev, "vusb3v1"); >> + if (IS_ERR(madc->usb3v1)) >> + return -ENODEV; >> + >> + ret = regulator_enable(madc->usb3v1); >> + if (ret) >> + dev_err(madc->dev, "could not be enable 3v1 bias regulator\n"); > > please fix wording, "could not enable usb 3v1 bias regulator" probably > >> + >> return 0; >> >> err_i2c: >> @@ -867,6 +878,9 @@ static int twl4030_madc_remove(struct platform_device *pdev) >> twl4030_madc_set_current_generator(madc, 0, 0); >> twl4030_madc_set_power(madc, 0); >> >> + regulator_disable(madc->usb3v1); >> + regulator_put(madc->usb3v1); >> + >> return 0; >> } >> >> diff --git a/drivers/phy/phy-twl4030-usb.c b/drivers/phy/phy-twl4030-usb.c >> index 7b04bef..88fc7d7 100644 >> --- a/drivers/phy/phy-twl4030-usb.c >> +++ b/drivers/phy/phy-twl4030-usb.c >> @@ -144,6 +144,9 @@ >> #define PMBR1 0x0D >> #define GPIO_USB_4PIN_ULPI_2430C (3 << 0) >> >> +#define TWL4030_USB_SEL_MADC_MCPC (1<<3) >> +#define TWL4030_USB_CARKIT_ANA_CTRL 0xBB >> + >> struct twl4030_usb { >> struct usb_phy phy; >> struct device *dev; >> @@ -459,6 +462,10 @@ static int twl4030_phy_power_on(struct phy *phy) >> twl4030_i2c_access(twl, 0); >> schedule_delayed_work(&twl->id_workaround_work, 0); >> >> + twl4030_usb_write(twl, TWL4030_USB_CARKIT_ANA_CTRL, >> + twl4030_usb_read(twl, TWL4030_USB_CARKIT_ANA_CTRL) | >> + TWL4030_USB_SEL_MADC_MCPC); >> + > > shouldn't this be done is the adc driver? > >> return 0; >> } >> >> > > -- > > Peter Meerwald > +43-664-2444418 (mobile) ^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH] Fix incomplete initialization of ADC[3:6]
@ 2015-07-16 22:20 Adam YH Lee
2015-07-16 22:20 ` [PATCH] [TWL4030 MADC] Fix ADC[3:6] readings Adam YH Lee
0 siblings, 1 reply; 10+ messages in thread
From: Adam YH Lee @ 2015-07-16 22:20 UTC (permalink / raw)
To: linux-arm-kernel
TPS65950(TWL4030) paired with OMAP3 is used in devices such as Beagleboard and
Gumstix Overo COMs. Its ADCs from 3 to 6 seem to be broken [1][2][3].
The ADC readings for these pins are stuck at near 0v for these two reasons:
- 3v1 bias regulator (vusb3v1) is off unless USB-otg is being used
- pins are not configured to attach as ADC
This patch attempts to fix these issues by making sure 3v1 regulator is enabled
and pins are correctly configured as ADC inputs.
[1] http://comments.gmane.org/gmane.linux.ports.arm.omap/83698
[2] http://gumstix.8.x6.nabble.com/twl4030-madc-low-read-value-td4967139.html#none
[3] https://e2e.ti.com/support/power_management/pmu/f/43/t/732
Adam YH Lee (1):
[TWL4030 MADC] Fix ADC[3:6] readings
drivers/iio/adc/twl4030-madc.c | 14 ++++++++++++++
drivers/phy/phy-twl4030-usb.c | 7 +++++++
2 files changed, 21 insertions(+)
--
2.1.4
^ permalink raw reply [flat|nested] 10+ messages in thread* [PATCH] [TWL4030 MADC] Fix ADC[3:6] readings 2015-07-16 22:20 [PATCH] Fix incomplete initialization of ADC[3:6] Adam YH Lee @ 2015-07-16 22:20 ` Adam YH Lee 2015-07-17 9:00 ` Sebastian Reichel 0 siblings, 1 reply; 10+ messages in thread From: Adam YH Lee @ 2015-07-16 22:20 UTC (permalink / raw) To: linux-arm-kernel MADC[3:6] reads incorrect values without these two following changes: - enable the 3v1 bias regulator for ADC[3:6] - configure ADC[3:6] lines as input, not as USB Signed-off-by: Adam YH Lee <adam.yh.lee@gmail.com> --- drivers/iio/adc/twl4030-madc.c | 14 ++++++++++++++ drivers/phy/phy-twl4030-usb.c | 7 +++++++ 2 files changed, 21 insertions(+) diff --git a/drivers/iio/adc/twl4030-madc.c b/drivers/iio/adc/twl4030-madc.c index 94c5f05..b5020ab 100644 --- a/drivers/iio/adc/twl4030-madc.c +++ b/drivers/iio/adc/twl4030-madc.c @@ -45,6 +45,7 @@ #include <linux/types.h> #include <linux/gfp.h> #include <linux/err.h> +#include <linux/regulator/consumer.h> #include <linux/iio/iio.h> @@ -52,6 +53,7 @@ * struct twl4030_madc_data - a container for madc info * @dev: Pointer to device structure for madc * @lock: Mutex protecting this data structure + * @regulator: Pointer to bias regulator for madc * @requests: Array of request struct corresponding to SW1, SW2 and RT * @use_second_irq: IRQ selection (main or co-processor) * @imr: Interrupt mask register of MADC @@ -60,6 +62,7 @@ struct twl4030_madc_data { struct device *dev; struct mutex lock; /* mutex protecting this data structure */ + struct regulator *usb3v1; struct twl4030_madc_request requests[TWL4030_MADC_NUM_METHODS]; bool use_second_irq; u8 imr; @@ -848,6 +851,14 @@ static int twl4030_madc_probe(struct platform_device *pdev) goto err_i2c; } + madc->usb3v1 = devm_regulator_get(madc->dev, "vusb3v1"); + if (IS_ERR(madc->usb3v1)) + return -ENODEV; + + ret = regulator_enable(madc->usb3v1); + if (ret) + dev_err(madc->dev, "could not be enable 3v1 bias regulator\n"); + return 0; err_i2c: @@ -867,6 +878,9 @@ static int twl4030_madc_remove(struct platform_device *pdev) twl4030_madc_set_current_generator(madc, 0, 0); twl4030_madc_set_power(madc, 0); + regulator_disable(madc->usb3v1); + regulator_put(madc->usb3v1); + return 0; } diff --git a/drivers/phy/phy-twl4030-usb.c b/drivers/phy/phy-twl4030-usb.c index 7b04bef..88fc7d7 100644 --- a/drivers/phy/phy-twl4030-usb.c +++ b/drivers/phy/phy-twl4030-usb.c @@ -144,6 +144,9 @@ #define PMBR1 0x0D #define GPIO_USB_4PIN_ULPI_2430C (3 << 0) +#define TWL4030_USB_SEL_MADC_MCPC (1<<3) +#define TWL4030_USB_CARKIT_ANA_CTRL 0xBB + struct twl4030_usb { struct usb_phy phy; struct device *dev; @@ -459,6 +462,10 @@ static int twl4030_phy_power_on(struct phy *phy) twl4030_i2c_access(twl, 0); schedule_delayed_work(&twl->id_workaround_work, 0); + twl4030_usb_write(twl, TWL4030_USB_CARKIT_ANA_CTRL, + twl4030_usb_read(twl, TWL4030_USB_CARKIT_ANA_CTRL) | + TWL4030_USB_SEL_MADC_MCPC); + return 0; } -- 2.1.4 ^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH] [TWL4030 MADC] Fix ADC[3:6] readings 2015-07-16 22:20 ` [PATCH] [TWL4030 MADC] Fix ADC[3:6] readings Adam YH Lee @ 2015-07-17 9:00 ` Sebastian Reichel 2015-07-17 9:42 ` Peter Meerwald 0 siblings, 1 reply; 10+ messages in thread From: Sebastian Reichel @ 2015-07-17 9:00 UTC (permalink / raw) To: linux-arm-kernel Hi, To get a chance of this patch being considered for inclusion, you should send this to the maintainers of the phy and iio framework. There is a high chance, that none of them will see your mail. On Thu, Jul 16, 2015 at 03:20:27PM -0700, Adam YH Lee wrote: > MADC[3:6] reads incorrect values without these two following changes: uhm MADC[3:6] are externally available analog inputs. Your change will result in them being tied to the USB module. > - enable the 3v1 bias regulator for ADC[3:6] The regulator is not required for correct MADC functionality, but for correct USB measureing. The regulator should not be requested by the madc module, but by the usb module, which is connected to the madc. > - configure ADC[3:6] lines as input, not as USB I don't think that should be done for all boards. > [...] -- Sebastian -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: Digital signature URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20150717/e0810b09/attachment.sig> ^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH] [TWL4030 MADC] Fix ADC[3:6] readings 2015-07-17 9:00 ` Sebastian Reichel @ 2015-07-17 9:42 ` Peter Meerwald 2015-07-20 17:47 ` Adam Lee 0 siblings, 1 reply; 10+ messages in thread From: Peter Meerwald @ 2015-07-17 9:42 UTC (permalink / raw) To: linux-arm-kernel Hello, adding linux-iio... > To get a chance of this patch being considered for inclusion, you > should send this to the maintainers of the phy and iio framework. > There is a high chance, that none of them will see your mail. > > On Thu, Jul 16, 2015 at 03:20:27PM -0700, Adam YH Lee wrote: > > MADC[3:6] reads incorrect values without these two following changes: > > uhm MADC[3:6] are externally available analog inputs. Your > change will result in them being tied to the USB module. change regarding TWL4030_USB_SEL_MADC_MCPC is necessary at least for some hardware revisions to get proper ADC values > > - enable the 3v1 bias regulator for ADC[3:6] > > The regulator is not required for correct MADC functionality, but > for correct USB measureing. The regulator should not be requested > by the madc module, but by the usb module, which is connected to > the madc. in my experience, the MADC exhibits several strange things, I wouldn't be surprised that this bias is somehow necessary for operation even if it is not what the spec says -- has this been tested? > > - configure ADC[3:6] lines as input, not as USB > > I don't think that should be done for all boards. > > > [...] > > -- Sebastian > -- Peter Meerwald +43-664-2444418 (mobile) ^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH] [TWL4030 MADC] Fix ADC[3:6] readings 2015-07-17 9:42 ` Peter Meerwald @ 2015-07-20 17:47 ` Adam Lee 2015-07-20 17:54 ` Jonathan Cameron 0 siblings, 1 reply; 10+ messages in thread From: Adam Lee @ 2015-07-20 17:47 UTC (permalink / raw) To: linux-arm-kernel Hello, here is some more context from the TPS65950's TRM [1]. Quoting from section 15.3.1.2.1 VUSB3V1 section: "VUSB3V1 is also used to bias analog multiplexers on the four MCPC pins between the carkit and the MADC (supplied by VINTANA2)." And from section 15.4.11. MADC Monitoring Using MCPC: "Four MCPC pins can be selected as analog conversion input pins by setting the CARKIT_ANA_CTRL[3] SEL_MADC_MCPC bit." My patch addresses both (set the register, and enable 3v1). And yes it has been tested on Gumstix Overo COMs (OMAP3 + TPS65950). Hope to hear from IIO maintainers! [1] http://www.droid-developers.org/images/2/21/Tps65950_TRM.pdf On Fri, Jul 17, 2015 at 2:42 AM, Peter Meerwald <pmeerw@pmeerw.net> wrote: > Hello, > > adding linux-iio... > >> To get a chance of this patch being considered for inclusion, you >> should send this to the maintainers of the phy and iio framework. >> There is a high chance, that none of them will see your mail. >> >> On Thu, Jul 16, 2015 at 03:20:27PM -0700, Adam YH Lee wrote: >> > MADC[3:6] reads incorrect values without these two following changes: >> >> uhm MADC[3:6] are externally available analog inputs. Your >> change will result in them being tied to the USB module. > > change regarding TWL4030_USB_SEL_MADC_MCPC is necessary at > least for some hardware revisions to get proper ADC values > >> > - enable the 3v1 bias regulator for ADC[3:6] >> >> The regulator is not required for correct MADC functionality, but >> for correct USB measureing. The regulator should not be requested >> by the madc module, but by the usb module, which is connected to >> the madc. > > in my experience, the MADC exhibits several strange things, I wouldn't be > surprised that this bias is somehow necessary for operation even if it is > not what the spec says -- has this been tested? > >> > - configure ADC[3:6] lines as input, not as USB >> >> I don't think that should be done for all boards. >> >> > [...] >> >> -- Sebastian >> > > -- > > Peter Meerwald > +43-664-2444418 (mobile) ^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH] [TWL4030 MADC] Fix ADC[3:6] readings 2015-07-20 17:47 ` Adam Lee @ 2015-07-20 17:54 ` Jonathan Cameron 2015-07-20 18:23 ` Adam Lee 0 siblings, 1 reply; 10+ messages in thread From: Jonathan Cameron @ 2015-07-20 17:54 UTC (permalink / raw) To: linux-arm-kernel On 20/07/15 18:47, Adam Lee wrote: > Hello, here is some more context from the TPS65950's TRM [1]. > > Quoting from section 15.3.1.2.1 VUSB3V1 section: > > "VUSB3V1 is also used to bias analog multiplexers on the four MCPC > pins between the carkit and the MADC (supplied by VINTANA2)." > > > And from section 15.4.11. MADC Monitoring Using MCPC: > > "Four MCPC pins can be selected as analog conversion input pins by > setting the CARKIT_ANA_CTRL[3] SEL_MADC_MCPC bit." > > My patch addresses both (set the register, and enable 3v1). And yes it > has been tested on Gumstix Overo COMs (OMAP3 + TPS65950). > > Hope to hear from IIO maintainers! I dug the patch out of the archives. Looks clear enough to me. Could you resend the patch with linux-iio cc'd? I will want an Ack from Sebastian. Thanks, Jonathan > > [1] http://www.droid-developers.org/images/2/21/Tps65950_TRM.pdf > > On Fri, Jul 17, 2015 at 2:42 AM, Peter Meerwald <pmeerw@pmeerw.net> wrote: >> Hello, >> >> adding linux-iio... >> >>> To get a chance of this patch being considered for inclusion, you >>> should send this to the maintainers of the phy and iio framework. >>> There is a high chance, that none of them will see your mail. >>> >>> On Thu, Jul 16, 2015 at 03:20:27PM -0700, Adam YH Lee wrote: >>>> MADC[3:6] reads incorrect values without these two following changes: >>> >>> uhm MADC[3:6] are externally available analog inputs. Your >>> change will result in them being tied to the USB module. >> >> change regarding TWL4030_USB_SEL_MADC_MCPC is necessary at >> least for some hardware revisions to get proper ADC values >> >>>> - enable the 3v1 bias regulator for ADC[3:6] >>> >>> The regulator is not required for correct MADC functionality, but >>> for correct USB measureing. The regulator should not be requested >>> by the madc module, but by the usb module, which is connected to >>> the madc. >> >> in my experience, the MADC exhibits several strange things, I wouldn't be >> surprised that this bias is somehow necessary for operation even if it is >> not what the spec says -- has this been tested? >> >>>> - configure ADC[3:6] lines as input, not as USB >>> >>> I don't think that should be done for all boards. >>> >>>> [...] >>> >>> -- Sebastian >>> >> >> -- >> >> Peter Meerwald >> +43-664-2444418 (mobile) > -- > To unsubscribe from this list: send the line "unsubscribe linux-iio" in > the body of a message to majordomo at vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > ^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH] [TWL4030 MADC] Fix ADC[3:6] readings 2015-07-20 17:54 ` Jonathan Cameron @ 2015-07-20 18:23 ` Adam Lee 0 siblings, 0 replies; 10+ messages in thread From: Adam Lee @ 2015-07-20 18:23 UTC (permalink / raw) To: linux-arm-kernel Hello Jonathan, I sent the same patch with linux-iio cc'd. I expanded the cover letter with the quotes from TI's documents, but the text has been removed in the email somehow. The discussion in this thread should be enough (I think) for linux-iio maintainers, so we will see! Thanks, Adam On Mon, Jul 20, 2015 at 10:54 AM, Jonathan Cameron <jic23@kernel.org> wrote: > On 20/07/15 18:47, Adam Lee wrote: >> Hello, here is some more context from the TPS65950's TRM [1]. >> >> Quoting from section 15.3.1.2.1 VUSB3V1 section: >> >> "VUSB3V1 is also used to bias analog multiplexers on the four MCPC >> pins between the carkit and the MADC (supplied by VINTANA2)." >> >> >> And from section 15.4.11. MADC Monitoring Using MCPC: >> >> "Four MCPC pins can be selected as analog conversion input pins by >> setting the CARKIT_ANA_CTRL[3] SEL_MADC_MCPC bit." >> >> My patch addresses both (set the register, and enable 3v1). And yes it >> has been tested on Gumstix Overo COMs (OMAP3 + TPS65950). >> >> Hope to hear from IIO maintainers! > I dug the patch out of the archives. > > Looks clear enough to me. Could you resend the patch with linux-iio cc'd? > I will want an Ack from Sebastian. > > Thanks, > > Jonathan > >> >> [1] http://www.droid-developers.org/images/2/21/Tps65950_TRM.pdf >> >> On Fri, Jul 17, 2015 at 2:42 AM, Peter Meerwald <pmeerw@pmeerw.net> wrote: >>> Hello, >>> >>> adding linux-iio... >>> >>>> To get a chance of this patch being considered for inclusion, you >>>> should send this to the maintainers of the phy and iio framework. >>>> There is a high chance, that none of them will see your mail. >>>> >>>> On Thu, Jul 16, 2015 at 03:20:27PM -0700, Adam YH Lee wrote: >>>>> MADC[3:6] reads incorrect values without these two following changes: >>>> >>>> uhm MADC[3:6] are externally available analog inputs. Your >>>> change will result in them being tied to the USB module. >>> >>> change regarding TWL4030_USB_SEL_MADC_MCPC is necessary at >>> least for some hardware revisions to get proper ADC values >>> >>>>> - enable the 3v1 bias regulator for ADC[3:6] >>>> >>>> The regulator is not required for correct MADC functionality, but >>>> for correct USB measureing. The regulator should not be requested >>>> by the madc module, but by the usb module, which is connected to >>>> the madc. >>> >>> in my experience, the MADC exhibits several strange things, I wouldn't be >>> surprised that this bias is somehow necessary for operation even if it is >>> not what the spec says -- has this been tested? >>> >>>>> - configure ADC[3:6] lines as input, not as USB >>>> >>>> I don't think that should be done for all boards. >>>> >>>>> [...] >>>> >>>> -- Sebastian >>>> >>> >>> -- >>> >>> Peter Meerwald >>> +43-664-2444418 (mobile) >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-iio" in >> the body of a message to majordomo at vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > ^ permalink raw reply [flat|nested] 10+ messages in thread
end of thread, other threads:[~2015-07-20 19:19 UTC | newest] Thread overview: 10+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2015-07-20 18:14 [PATCH] Fix incomplete initialization of ADC[3:6]$ Adam YH Lee 2015-07-20 18:14 ` [PATCH] [TWL4030 MADC] Fix ADC[3:6] readings Adam YH Lee 2015-07-20 18:54 ` Peter Meerwald 2015-07-20 19:19 ` Adam Lee -- strict thread matches above, loose matches on Subject: below -- 2015-07-16 22:20 [PATCH] Fix incomplete initialization of ADC[3:6] Adam YH Lee 2015-07-16 22:20 ` [PATCH] [TWL4030 MADC] Fix ADC[3:6] readings Adam YH Lee 2015-07-17 9:00 ` Sebastian Reichel 2015-07-17 9:42 ` Peter Meerwald 2015-07-20 17:47 ` Adam Lee 2015-07-20 17:54 ` Jonathan Cameron 2015-07-20 18:23 ` Adam Lee
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