* [PATCH v2 1/2] mfd: ti_am335x_tscadc: Use PLATFORM_DEVID_AUTO while registering mfd cells
2018-12-03 8:01 [PATCH v2 0/2] tscadc: Couple of fixes Vignesh R
@ 2018-12-03 8:01 ` Vignesh R
2018-12-03 11:35 ` Lee Jones
2018-12-03 8:01 ` [PATCH v2 2/2] iio: adc: ti_am335x_tscadc: Improve accuracy of measurement Vignesh R
2018-12-03 11:34 ` [GIT PULL] Immutable branch between MFD and IIO due for the v4.21 merge window Lee Jones
2 siblings, 1 reply; 5+ messages in thread
From: Vignesh R @ 2018-12-03 8:01 UTC (permalink / raw)
To: Lee Jones
Cc: Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Vignesh R, linux-iio, linux-omap,
linux-kernel
Use PLATFORM_DEVID_AUTO to number mfd cells while registering, so that
different instances are uniquely identified. This is required in order
to support registering of multiple instances of same ti_am335x_tscadc IP.
Signed-off-by: Vignesh R <vigneshr@ti.com>
---
v2: use PLATFORM_DEVID_AUTO as suggested by Lee Jones
drivers/mfd/ti_am335x_tscadc.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335x_tscadc.c
index c2d47d78705b..fd111296b959 100644
--- a/drivers/mfd/ti_am335x_tscadc.c
+++ b/drivers/mfd/ti_am335x_tscadc.c
@@ -264,8 +264,9 @@ static int ti_tscadc_probe(struct platform_device *pdev)
cell->pdata_size = sizeof(tscadc);
}
- err = mfd_add_devices(&pdev->dev, pdev->id, tscadc->cells,
- tscadc->used_cells, NULL, 0, NULL);
+ err = mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO,
+ tscadc->cells, tscadc->used_cells, NULL,
+ 0, NULL);
if (err < 0)
goto err_disable_clk;
--
2.19.2
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH v2 1/2] mfd: ti_am335x_tscadc: Use PLATFORM_DEVID_AUTO while registering mfd cells
2018-12-03 8:01 ` [PATCH v2 1/2] mfd: ti_am335x_tscadc: Use PLATFORM_DEVID_AUTO while registering mfd cells Vignesh R
@ 2018-12-03 11:35 ` Lee Jones
0 siblings, 0 replies; 5+ messages in thread
From: Lee Jones @ 2018-12-03 11:35 UTC (permalink / raw)
To: Vignesh R
Cc: Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, linux-iio, linux-omap, linux-kernel
On Mon, 03 Dec 2018, Vignesh R wrote:
> Use PLATFORM_DEVID_AUTO to number mfd cells while registering, so that
> different instances are uniquely identified. This is required in order
> to support registering of multiple instances of same ti_am335x_tscadc IP.
>
> Signed-off-by: Vignesh R <vigneshr@ti.com>
> ---
> v2: use PLATFORM_DEVID_AUTO as suggested by Lee Jones
>
> drivers/mfd/ti_am335x_tscadc.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
Applied, thanks.
--
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH v2 2/2] iio: adc: ti_am335x_tscadc: Improve accuracy of measurement
2018-12-03 8:01 [PATCH v2 0/2] tscadc: Couple of fixes Vignesh R
2018-12-03 8:01 ` [PATCH v2 1/2] mfd: ti_am335x_tscadc: Use PLATFORM_DEVID_AUTO while registering mfd cells Vignesh R
@ 2018-12-03 8:01 ` Vignesh R
2018-12-03 11:34 ` [GIT PULL] Immutable branch between MFD and IIO due for the v4.21 merge window Lee Jones
2 siblings, 0 replies; 5+ messages in thread
From: Vignesh R @ 2018-12-03 8:01 UTC (permalink / raw)
To: Lee Jones
Cc: Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Vignesh R, linux-iio, linux-omap,
linux-kernel
When performing single ended measurements with TSCADC, its recommended
to set negative input (SEL_INM_SWC_3_0) of ADC step to ADC's VREFN in the
corresponding STEP_CONFIGx register.
Also, the positive(SEL_RFP_SWC_2_0) and negative(SEL_RFM_SWC_1_0)
reference voltage for ADC step needs to be set to VREFP and VREFN
respectively in STEP_CONFIGx register.
Without these changes, there may be variation of as much as ~2% in the
ADC's digital output which is bad for precise measurement.
Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
---
v2: No change
drivers/iio/adc/ti_am335x_adc.c | 5 ++++-
include/linux/mfd/ti_am335x_tscadc.h | 4 ++++
2 files changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index cafb1dcadc48..9d984f2a8ba7 100644
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -142,7 +142,10 @@ static void tiadc_step_config(struct iio_dev *indio_dev)
stepconfig |= STEPCONFIG_MODE_SWCNT;
tiadc_writel(adc_dev, REG_STEPCONFIG(steps),
- stepconfig | STEPCONFIG_INP(chan));
+ stepconfig | STEPCONFIG_INP(chan) |
+ STEPCONFIG_INM_ADCREFM |
+ STEPCONFIG_RFP_VREFP |
+ STEPCONFIG_RFM_VREFN);
if (adc_dev->open_delay[i] > STEPDELAY_OPEN_MASK) {
dev_warn(dev, "chan %d open delay truncating to 0x3FFFF\n",
diff --git a/include/linux/mfd/ti_am335x_tscadc.h b/include/linux/mfd/ti_am335x_tscadc.h
index b9a53e013bff..483168403ae5 100644
--- a/include/linux/mfd/ti_am335x_tscadc.h
+++ b/include/linux/mfd/ti_am335x_tscadc.h
@@ -78,6 +78,8 @@
#define STEPCONFIG_YNN BIT(8)
#define STEPCONFIG_XNP BIT(9)
#define STEPCONFIG_YPN BIT(10)
+#define STEPCONFIG_RFP(val) ((val) << 12)
+#define STEPCONFIG_RFP_VREFP (0x3 << 12)
#define STEPCONFIG_INM_MASK (0xF << 15)
#define STEPCONFIG_INM(val) ((val) << 15)
#define STEPCONFIG_INM_ADCREFM STEPCONFIG_INM(8)
@@ -86,6 +88,8 @@
#define STEPCONFIG_INP_AN4 STEPCONFIG_INP(4)
#define STEPCONFIG_INP_ADCREFM STEPCONFIG_INP(8)
#define STEPCONFIG_FIFO1 BIT(26)
+#define STEPCONFIG_RFM(val) ((val) << 23)
+#define STEPCONFIG_RFM_VREFN (0x3 << 23)
/* Delay register */
#define STEPDELAY_OPEN_MASK (0x3FFFF << 0)
--
2.19.2
^ permalink raw reply related [flat|nested] 5+ messages in thread* [GIT PULL] Immutable branch between MFD and IIO due for the v4.21 merge window
2018-12-03 8:01 [PATCH v2 0/2] tscadc: Couple of fixes Vignesh R
2018-12-03 8:01 ` [PATCH v2 1/2] mfd: ti_am335x_tscadc: Use PLATFORM_DEVID_AUTO while registering mfd cells Vignesh R
2018-12-03 8:01 ` [PATCH v2 2/2] iio: adc: ti_am335x_tscadc: Improve accuracy of measurement Vignesh R
@ 2018-12-03 11:34 ` Lee Jones
2 siblings, 0 replies; 5+ messages in thread
From: Lee Jones @ 2018-12-03 11:34 UTC (permalink / raw)
To: Vignesh R
Cc: Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, linux-iio, linux-omap, linux-kernel
Enjoy!
The following changes since commit 651022382c7f8da46cb4872a545ee1da6d097d2a:
Linux 4.20-rc1 (2018-11-04 15:37:52 -0800)
are available in the Git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd.git ib-mfd-iio-v4.21
for you to fetch changes up to 4b3ab9372ffa569827c8f7b7ffc7b69ba544a3bd:
iio: adc: ti_am335x_tscadc: Improve accuracy of measurement (2018-12-03 11:33:20 +0000)
----------------------------------------------------------------
Immutable branch between MFD and IIO due for the v4.21 merge window
----------------------------------------------------------------
Vignesh R (2):
mfd: ti_am335x_tscadc: Use PLATFORM_DEVID_AUTO while registering mfd cells
iio: adc: ti_am335x_tscadc: Improve accuracy of measurement
drivers/iio/adc/ti_am335x_adc.c | 5 ++++-
drivers/mfd/ti_am335x_tscadc.c | 5 +++--
include/linux/mfd/ti_am335x_tscadc.h | 4 ++++
3 files changed, 11 insertions(+), 3 deletions(-)
--
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
^ permalink raw reply [flat|nested] 5+ messages in thread