* [PATCH 0/3] iio:adc:at91-sama5d2: add support for signed conversion
@ 2016-03-03 16:09 Ludovic Desroches
2016-03-03 16:09 ` [PATCH 1/3] iio:adc:at91-sama5d2: fix typo Ludovic Desroches
` (2 more replies)
0 siblings, 3 replies; 7+ messages in thread
From: Ludovic Desroches @ 2016-03-03 16:09 UTC (permalink / raw)
To: linux-arm-kernel
Hi,
This set of patches does some cleanup in the code and export channels for
signed and unsigned conversions.
Ludovic Desroches (3):
iio:adc:at91-sama5d2: fix typo
iio:adc:at91-sama5d2: fix identation
iio:adc:at91-sama5d2: add support for signed conversion
drivers/iio/adc/at91-sama5d2_adc.c | 101 ++++++++++++++++++++++++++++---------
1 file changed, 77 insertions(+), 24 deletions(-)
--
2.5.0
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH 1/3] iio:adc:at91-sama5d2: fix typo
2016-03-03 16:09 [PATCH 0/3] iio:adc:at91-sama5d2: add support for signed conversion Ludovic Desroches
@ 2016-03-03 16:09 ` Ludovic Desroches
2016-03-05 15:02 ` Jonathan Cameron
2016-03-03 16:09 ` [PATCH 2/3] iio:adc:at91-sama5d2: fix identation Ludovic Desroches
2016-03-03 16:09 ` [PATCH 3/3] iio:adc:at91-sama5d2: add support for signed conversion Ludovic Desroches
2 siblings, 1 reply; 7+ messages in thread
From: Ludovic Desroches @ 2016-03-03 16:09 UTC (permalink / raw)
To: linux-arm-kernel
Fix typo in the name of a macro.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
---
drivers/iio/adc/at91-sama5d2_adc.c | 26 +++++++++++++-------------
1 file changed, 13 insertions(+), 13 deletions(-)
diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
index dbee13a..33bacec 100644
--- a/drivers/iio/adc/at91-sama5d2_adc.c
+++ b/drivers/iio/adc/at91-sama5d2_adc.c
@@ -140,7 +140,7 @@
/* Version Register */
#define AT91_SAMA5D2_VERSION 0xfc
-#define AT91_AT91_SAMA5D2_CHAN(num, addr) \
+#define AT91_SAMA5D2_CHAN(num, addr) \
{ \
.type = IIO_VOLTAGE, \
.channel = num, \
@@ -185,18 +185,18 @@ struct at91_adc_state {
};
static const struct iio_chan_spec at91_adc_channels[] = {
- AT91_AT91_SAMA5D2_CHAN(0, 0x50),
- AT91_AT91_SAMA5D2_CHAN(1, 0x54),
- AT91_AT91_SAMA5D2_CHAN(2, 0x58),
- AT91_AT91_SAMA5D2_CHAN(3, 0x5c),
- AT91_AT91_SAMA5D2_CHAN(4, 0x60),
- AT91_AT91_SAMA5D2_CHAN(5, 0x64),
- AT91_AT91_SAMA5D2_CHAN(6, 0x68),
- AT91_AT91_SAMA5D2_CHAN(7, 0x6c),
- AT91_AT91_SAMA5D2_CHAN(8, 0x70),
- AT91_AT91_SAMA5D2_CHAN(9, 0x74),
- AT91_AT91_SAMA5D2_CHAN(10, 0x78),
- AT91_AT91_SAMA5D2_CHAN(11, 0x7c),
+ AT91_SAMA5D2_CHAN(0, 0x50),
+ AT91_SAMA5D2_CHAN(1, 0x54),
+ AT91_SAMA5D2_CHAN(2, 0x58),
+ AT91_SAMA5D2_CHAN(3, 0x5c),
+ AT91_SAMA5D2_CHAN(4, 0x60),
+ AT91_SAMA5D2_CHAN(5, 0x64),
+ AT91_SAMA5D2_CHAN(6, 0x68),
+ AT91_SAMA5D2_CHAN(7, 0x6c),
+ AT91_SAMA5D2_CHAN(8, 0x70),
+ AT91_SAMA5D2_CHAN(9, 0x74),
+ AT91_SAMA5D2_CHAN(10, 0x78),
+ AT91_SAMA5D2_CHAN(11, 0x7c),
};
static unsigned at91_adc_startup_time(unsigned startup_time_min,
--
2.5.0
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [PATCH 2/3] iio:adc:at91-sama5d2: fix identation
2016-03-03 16:09 [PATCH 0/3] iio:adc:at91-sama5d2: add support for signed conversion Ludovic Desroches
2016-03-03 16:09 ` [PATCH 1/3] iio:adc:at91-sama5d2: fix typo Ludovic Desroches
@ 2016-03-03 16:09 ` Ludovic Desroches
2016-03-05 15:03 ` Jonathan Cameron
2016-03-03 16:09 ` [PATCH 3/3] iio:adc:at91-sama5d2: add support for signed conversion Ludovic Desroches
2 siblings, 1 reply; 7+ messages in thread
From: Ludovic Desroches @ 2016-03-03 16:09 UTC (permalink / raw)
To: linux-arm-kernel
Remove some extra tabs.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
---
drivers/iio/adc/at91-sama5d2_adc.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
index 33bacec..5bc038f 100644
--- a/drivers/iio/adc/at91-sama5d2_adc.c
+++ b/drivers/iio/adc/at91-sama5d2_adc.c
@@ -92,13 +92,13 @@
/* Last Converted Data Register */
#define AT91_SAMA5D2_LCDR 0x20
/* Interrupt Enable Register */
-#define AT91_SAMA5D2_IER 0x24
+#define AT91_SAMA5D2_IER 0x24
/* Interrupt Disable Register */
-#define AT91_SAMA5D2_IDR 0x28
+#define AT91_SAMA5D2_IDR 0x28
/* Interrupt Mask Register */
-#define AT91_SAMA5D2_IMR 0x2c
+#define AT91_SAMA5D2_IMR 0x2c
/* Interrupt Status Register */
-#define AT91_SAMA5D2_ISR 0x30
+#define AT91_SAMA5D2_ISR 0x30
/* Last Channel Trigger Mode Register */
#define AT91_SAMA5D2_LCTMR 0x34
/* Last Channel Compare Window Register */
@@ -106,17 +106,17 @@
/* Overrun Status Register */
#define AT91_SAMA5D2_OVER 0x3c
/* Extended Mode Register */
-#define AT91_SAMA5D2_EMR 0x40
+#define AT91_SAMA5D2_EMR 0x40
/* Compare Window Register */
-#define AT91_SAMA5D2_CWR 0x44
+#define AT91_SAMA5D2_CWR 0x44
/* Channel Gain Register */
-#define AT91_SAMA5D2_CGR 0x48
+#define AT91_SAMA5D2_CGR 0x48
/* Channel Offset Register */
-#define AT91_SAMA5D2_COR 0x4c
+#define AT91_SAMA5D2_COR 0x4c
/* Channel Data Register 0 */
#define AT91_SAMA5D2_CDR0 0x50
/* Analog Control Register */
-#define AT91_SAMA5D2_ACR 0x94
+#define AT91_SAMA5D2_ACR 0x94
/* Touchscreen Mode Register */
#define AT91_SAMA5D2_TSMR 0xb0
/* Touchscreen X Position Register */
@@ -130,7 +130,7 @@
/* Correction Select Register */
#define AT91_SAMA5D2_COSR 0xd0
/* Correction Value Register */
-#define AT91_SAMA5D2_CVR 0xd4
+#define AT91_SAMA5D2_CVR 0xd4
/* Channel Error Correction Register */
#define AT91_SAMA5D2_CECR 0xd8
/* Write Protection Mode Register */
--
2.5.0
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [PATCH 3/3] iio:adc:at91-sama5d2: add support for signed conversion
2016-03-03 16:09 [PATCH 0/3] iio:adc:at91-sama5d2: add support for signed conversion Ludovic Desroches
2016-03-03 16:09 ` [PATCH 1/3] iio:adc:at91-sama5d2: fix typo Ludovic Desroches
2016-03-03 16:09 ` [PATCH 2/3] iio:adc:at91-sama5d2: fix identation Ludovic Desroches
@ 2016-03-03 16:09 ` Ludovic Desroches
2016-03-05 15:16 ` Jonathan Cameron
2 siblings, 1 reply; 7+ messages in thread
From: Ludovic Desroches @ 2016-03-03 16:09 UTC (permalink / raw)
To: linux-arm-kernel
The at91-sama5d2 ADC controller can achieve unsigned and signed
conversion. For each channel, a signed and an unsigned variant are
created.
We can't set the sign mode for each channel. For that reason, the
controller has to be configured upon conversion requests.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
---
drivers/iio/adc/at91-sama5d2_adc.c | 81 +++++++++++++++++++++++++++++++-------
1 file changed, 67 insertions(+), 14 deletions(-)
diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
index 5bc038f..d4bf73f 100644
--- a/drivers/iio/adc/at91-sama5d2_adc.c
+++ b/drivers/iio/adc/at91-sama5d2_adc.c
@@ -105,8 +105,26 @@
#define AT91_SAMA5D2_LCCWR 0x38
/* Overrun Status Register */
#define AT91_SAMA5D2_OVER 0x3c
+
/* Extended Mode Register */
#define AT91_SAMA5D2_EMR 0x40
+/* Sign Mode */
+#define AT91_SAMA5D2_EMR_SIGNMODE(v) ((v) << 25)
+/*
+ * Single-Ended channels: Unsigned conversions.
+ * Differential channels: Signed conversions.
+ */
+#define AT91_SAMA5D2_EMR_SE_UNSG_DF_SIGN 0
+/*
+ * Single-Ended channels: Signed conversions.
+ * Differential channels: Unsigned conversions.
+ */
+#define AT91_SAMA5D2_EMR_SE_SIGN_DF_UNSG 1
+/* All channels: Unsigned conversions */
+#define AT91_SAMA5D2_EMR_ALL_UNSIGNED 2
+/* All channels: Signed conversions */
+#define AT91_SAMA5D2_EMR_ALL_SIGNED 3
+
/* Compare Window Register */
#define AT91_SAMA5D2_CWR 0x44
/* Channel Gain Register */
@@ -140,13 +158,14 @@
/* Version Register */
#define AT91_SAMA5D2_VERSION 0xfc
-#define AT91_SAMA5D2_CHAN(num, addr) \
+#define AT91_SAMA5D2_VOLTAGE_CHANNEL(num, addr, sign_mode) \
{ \
.type = IIO_VOLTAGE, \
.channel = num, \
.address = addr, \
+ .extend_name = (sign_mode == 's') ? "signed" : "unsigned",\
.scan_type = { \
- .sign = 'u', \
+ .sign = sign_mode, \
.realbits = 12, \
}, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
@@ -156,6 +175,12 @@
.indexed = 1, \
}
+#define AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(num, addr) \
+ AT91_SAMA5D2_VOLTAGE_CHANNEL(num, addr, 's')
+
+#define AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(num, addr) \
+ AT91_SAMA5D2_VOLTAGE_CHANNEL(num, addr, 'u')
+
#define at91_adc_readl(st, reg) readl_relaxed(st->base + reg)
#define at91_adc_writel(st, reg, val) writel_relaxed(val, st->base + reg)
@@ -185,18 +210,30 @@ struct at91_adc_state {
};
static const struct iio_chan_spec at91_adc_channels[] = {
- AT91_SAMA5D2_CHAN(0, 0x50),
- AT91_SAMA5D2_CHAN(1, 0x54),
- AT91_SAMA5D2_CHAN(2, 0x58),
- AT91_SAMA5D2_CHAN(3, 0x5c),
- AT91_SAMA5D2_CHAN(4, 0x60),
- AT91_SAMA5D2_CHAN(5, 0x64),
- AT91_SAMA5D2_CHAN(6, 0x68),
- AT91_SAMA5D2_CHAN(7, 0x6c),
- AT91_SAMA5D2_CHAN(8, 0x70),
- AT91_SAMA5D2_CHAN(9, 0x74),
- AT91_SAMA5D2_CHAN(10, 0x78),
- AT91_SAMA5D2_CHAN(11, 0x7c),
+ AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(0, 0x50),
+ AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(1, 0x54),
+ AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(2, 0x58),
+ AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(3, 0x5c),
+ AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(4, 0x60),
+ AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(5, 0x64),
+ AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(6, 0x68),
+ AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(7, 0x6c),
+ AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(8, 0x70),
+ AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(9, 0x74),
+ AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(10, 0x78),
+ AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(11, 0x7c),
+ AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(0, 0x50),
+ AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(1, 0x54),
+ AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(2, 0x58),
+ AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(3, 0x5c),
+ AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(4, 0x60),
+ AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(5, 0x64),
+ AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(6, 0x68),
+ AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(7, 0x6c),
+ AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(8, 0x70),
+ AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(9, 0x74),
+ AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(10, 0x78),
+ AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(11, 0x7c),
};
static unsigned at91_adc_startup_time(unsigned startup_time_min,
@@ -278,6 +315,7 @@ static int at91_adc_read_raw(struct iio_dev *indio_dev,
int *val, int *val2, long mask)
{
struct at91_adc_state *st = iio_priv(indio_dev);
+ u32 emr;
int ret;
switch (mask) {
@@ -286,6 +324,19 @@ static int at91_adc_read_raw(struct iio_dev *indio_dev,
st->chan = chan;
+ /* Read EMR register and clear 'sign mode' field */
+ emr = at91_adc_readl(st, AT91_SAMA5D2_EMR)
+ & AT91_SAMA5D2_EMR_SIGNMODE(0);
+ /*
+ * Check if the user requested a conversion on a signed or
+ * unsigned channel.
+ */
+ if (chan->scan_type.sign == 's')
+ emr |= AT91_SAMA5D2_EMR_SIGNMODE(AT91_SAMA5D2_EMR_ALL_SIGNED);
+ else
+ emr |= AT91_SAMA5D2_EMR_SIGNMODE(AT91_SAMA5D2_EMR_ALL_UNSIGNED);
+
+ at91_adc_writel(st, AT91_SAMA5D2_EMR, emr);
at91_adc_writel(st, AT91_SAMA5D2_CHER, BIT(chan->channel));
at91_adc_writel(st, AT91_SAMA5D2_IER, BIT(chan->channel));
at91_adc_writel(st, AT91_SAMA5D2_CR, AT91_SAMA5D2_CR_START);
@@ -298,6 +349,8 @@ static int at91_adc_read_raw(struct iio_dev *indio_dev,
if (ret > 0) {
*val = st->conversion_value;
+ if (chan->scan_type.sign == 's')
+ *val = sign_extend32(*val, 11);
ret = IIO_VAL_INT;
st->conversion_done = false;
}
--
2.5.0
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [PATCH 1/3] iio:adc:at91-sama5d2: fix typo
2016-03-03 16:09 ` [PATCH 1/3] iio:adc:at91-sama5d2: fix typo Ludovic Desroches
@ 2016-03-05 15:02 ` Jonathan Cameron
0 siblings, 0 replies; 7+ messages in thread
From: Jonathan Cameron @ 2016-03-05 15:02 UTC (permalink / raw)
To: linux-arm-kernel
On 03/03/16 16:09, Ludovic Desroches wrote:
> Fix typo in the name of a macro.
>
> Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Oops ;)
Applied to the togreg branch of iio.git - initially pushed out as testing
for the autobuilders to play with it. Not sure if I will be doing another pull
request to Greg this cycle though...
Jonathan
> ---
> drivers/iio/adc/at91-sama5d2_adc.c | 26 +++++++++++++-------------
> 1 file changed, 13 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
> index dbee13a..33bacec 100644
> --- a/drivers/iio/adc/at91-sama5d2_adc.c
> +++ b/drivers/iio/adc/at91-sama5d2_adc.c
> @@ -140,7 +140,7 @@
> /* Version Register */
> #define AT91_SAMA5D2_VERSION 0xfc
>
> -#define AT91_AT91_SAMA5D2_CHAN(num, addr) \
> +#define AT91_SAMA5D2_CHAN(num, addr) \
> { \
> .type = IIO_VOLTAGE, \
> .channel = num, \
> @@ -185,18 +185,18 @@ struct at91_adc_state {
> };
>
> static const struct iio_chan_spec at91_adc_channels[] = {
> - AT91_AT91_SAMA5D2_CHAN(0, 0x50),
> - AT91_AT91_SAMA5D2_CHAN(1, 0x54),
> - AT91_AT91_SAMA5D2_CHAN(2, 0x58),
> - AT91_AT91_SAMA5D2_CHAN(3, 0x5c),
> - AT91_AT91_SAMA5D2_CHAN(4, 0x60),
> - AT91_AT91_SAMA5D2_CHAN(5, 0x64),
> - AT91_AT91_SAMA5D2_CHAN(6, 0x68),
> - AT91_AT91_SAMA5D2_CHAN(7, 0x6c),
> - AT91_AT91_SAMA5D2_CHAN(8, 0x70),
> - AT91_AT91_SAMA5D2_CHAN(9, 0x74),
> - AT91_AT91_SAMA5D2_CHAN(10, 0x78),
> - AT91_AT91_SAMA5D2_CHAN(11, 0x7c),
> + AT91_SAMA5D2_CHAN(0, 0x50),
> + AT91_SAMA5D2_CHAN(1, 0x54),
> + AT91_SAMA5D2_CHAN(2, 0x58),
> + AT91_SAMA5D2_CHAN(3, 0x5c),
> + AT91_SAMA5D2_CHAN(4, 0x60),
> + AT91_SAMA5D2_CHAN(5, 0x64),
> + AT91_SAMA5D2_CHAN(6, 0x68),
> + AT91_SAMA5D2_CHAN(7, 0x6c),
> + AT91_SAMA5D2_CHAN(8, 0x70),
> + AT91_SAMA5D2_CHAN(9, 0x74),
> + AT91_SAMA5D2_CHAN(10, 0x78),
> + AT91_SAMA5D2_CHAN(11, 0x7c),
> };
>
> static unsigned at91_adc_startup_time(unsigned startup_time_min,
>
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH 2/3] iio:adc:at91-sama5d2: fix identation
2016-03-03 16:09 ` [PATCH 2/3] iio:adc:at91-sama5d2: fix identation Ludovic Desroches
@ 2016-03-05 15:03 ` Jonathan Cameron
0 siblings, 0 replies; 7+ messages in thread
From: Jonathan Cameron @ 2016-03-05 15:03 UTC (permalink / raw)
To: linux-arm-kernel
On 03/03/16 16:09, Ludovic Desroches wrote:
> Remove some extra tabs.
>
> Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
I find it hard to care about this sort of patch, but whatever.
Applied to the togreg branch of iio.git - pushed out as testing.. etc etc.
Jonathan
> ---
> drivers/iio/adc/at91-sama5d2_adc.c | 20 ++++++++++----------
> 1 file changed, 10 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
> index 33bacec..5bc038f 100644
> --- a/drivers/iio/adc/at91-sama5d2_adc.c
> +++ b/drivers/iio/adc/at91-sama5d2_adc.c
> @@ -92,13 +92,13 @@
> /* Last Converted Data Register */
> #define AT91_SAMA5D2_LCDR 0x20
> /* Interrupt Enable Register */
> -#define AT91_SAMA5D2_IER 0x24
> +#define AT91_SAMA5D2_IER 0x24
> /* Interrupt Disable Register */
> -#define AT91_SAMA5D2_IDR 0x28
> +#define AT91_SAMA5D2_IDR 0x28
> /* Interrupt Mask Register */
> -#define AT91_SAMA5D2_IMR 0x2c
> +#define AT91_SAMA5D2_IMR 0x2c
> /* Interrupt Status Register */
> -#define AT91_SAMA5D2_ISR 0x30
> +#define AT91_SAMA5D2_ISR 0x30
> /* Last Channel Trigger Mode Register */
> #define AT91_SAMA5D2_LCTMR 0x34
> /* Last Channel Compare Window Register */
> @@ -106,17 +106,17 @@
> /* Overrun Status Register */
> #define AT91_SAMA5D2_OVER 0x3c
> /* Extended Mode Register */
> -#define AT91_SAMA5D2_EMR 0x40
> +#define AT91_SAMA5D2_EMR 0x40
> /* Compare Window Register */
> -#define AT91_SAMA5D2_CWR 0x44
> +#define AT91_SAMA5D2_CWR 0x44
> /* Channel Gain Register */
> -#define AT91_SAMA5D2_CGR 0x48
> +#define AT91_SAMA5D2_CGR 0x48
> /* Channel Offset Register */
> -#define AT91_SAMA5D2_COR 0x4c
> +#define AT91_SAMA5D2_COR 0x4c
> /* Channel Data Register 0 */
> #define AT91_SAMA5D2_CDR0 0x50
> /* Analog Control Register */
> -#define AT91_SAMA5D2_ACR 0x94
> +#define AT91_SAMA5D2_ACR 0x94
> /* Touchscreen Mode Register */
> #define AT91_SAMA5D2_TSMR 0xb0
> /* Touchscreen X Position Register */
> @@ -130,7 +130,7 @@
> /* Correction Select Register */
> #define AT91_SAMA5D2_COSR 0xd0
> /* Correction Value Register */
> -#define AT91_SAMA5D2_CVR 0xd4
> +#define AT91_SAMA5D2_CVR 0xd4
> /* Channel Error Correction Register */
> #define AT91_SAMA5D2_CECR 0xd8
> /* Write Protection Mode Register */
>
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH 3/3] iio:adc:at91-sama5d2: add support for signed conversion
2016-03-03 16:09 ` [PATCH 3/3] iio:adc:at91-sama5d2: add support for signed conversion Ludovic Desroches
@ 2016-03-05 15:16 ` Jonathan Cameron
0 siblings, 0 replies; 7+ messages in thread
From: Jonathan Cameron @ 2016-03-05 15:16 UTC (permalink / raw)
To: linux-arm-kernel
On 03/03/16 16:09, Ludovic Desroches wrote:
> The at91-sama5d2 ADC controller can achieve unsigned and signed
> conversion. For each channel, a signed and an unsigned variant are
> created.
> We can't set the sign mode for each channel. For that reason, the
> controller has to be configured upon conversion requests.
>
> Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Hmm. This should have a documentation patch as well as it breaks with
standard ABI. I really don't like using the extended name for this.
Firstly, doing so changes the presented ABI to userspace and makes
it non standard and secondly the channels are only differentiated at
some levels (sysfs attribute naming for example.) This really isn't
a generic enough approach.
I'd argue that we need a cleaner way of supporting this. Easy enough to add
an infomask element for this (I thought about an enum but _singed is clear
enough).
In this driver, that is all that would be needed. Gets more interesting
for buffered drivers, where we'd need to provide an alternative to how
the channel type readback works (probably an optional callback in iio_info).
(was envisioning this from the first, but have never implemented it).
Anyhow, I guess we need to do this generically at somepoint. Right now
all we need is the ABI for configuring on non buffered devices.
in_voltageX_signed with 1 and 0 as possible values should do the job I think...
Jonathan
> ---
> drivers/iio/adc/at91-sama5d2_adc.c | 81 +++++++++++++++++++++++++++++++-------
> 1 file changed, 67 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
> index 5bc038f..d4bf73f 100644
> --- a/drivers/iio/adc/at91-sama5d2_adc.c
> +++ b/drivers/iio/adc/at91-sama5d2_adc.c
> @@ -105,8 +105,26 @@
> #define AT91_SAMA5D2_LCCWR 0x38
> /* Overrun Status Register */
> #define AT91_SAMA5D2_OVER 0x3c
> +
> /* Extended Mode Register */
> #define AT91_SAMA5D2_EMR 0x40
> +/* Sign Mode */
> +#define AT91_SAMA5D2_EMR_SIGNMODE(v) ((v) << 25)
> +/*
> + * Single-Ended channels: Unsigned conversions.
> + * Differential channels: Signed conversions.
> + */
> +#define AT91_SAMA5D2_EMR_SE_UNSG_DF_SIGN 0
> +/*
> + * Single-Ended channels: Signed conversions.
> + * Differential channels: Unsigned conversions.
> + */
> +#define AT91_SAMA5D2_EMR_SE_SIGN_DF_UNSG 1
> +/* All channels: Unsigned conversions */
> +#define AT91_SAMA5D2_EMR_ALL_UNSIGNED 2
> +/* All channels: Signed conversions */
> +#define AT91_SAMA5D2_EMR_ALL_SIGNED 3
> +
> /* Compare Window Register */
> #define AT91_SAMA5D2_CWR 0x44
> /* Channel Gain Register */
> @@ -140,13 +158,14 @@
> /* Version Register */
> #define AT91_SAMA5D2_VERSION 0xfc
>
> -#define AT91_SAMA5D2_CHAN(num, addr) \
> +#define AT91_SAMA5D2_VOLTAGE_CHANNEL(num, addr, sign_mode) \
> { \
> .type = IIO_VOLTAGE, \
> .channel = num, \
> .address = addr, \
> + .extend_name = (sign_mode == 's') ? "signed" : "unsigned",\
> .scan_type = { \
> - .sign = 'u', \
> + .sign = sign_mode, \
> .realbits = 12, \
> }, \
> .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> @@ -156,6 +175,12 @@
> .indexed = 1, \
> }
>
> +#define AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(num, addr) \
> + AT91_SAMA5D2_VOLTAGE_CHANNEL(num, addr, 's')
> +
> +#define AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(num, addr) \
> + AT91_SAMA5D2_VOLTAGE_CHANNEL(num, addr, 'u')
> +
> #define at91_adc_readl(st, reg) readl_relaxed(st->base + reg)
> #define at91_adc_writel(st, reg, val) writel_relaxed(val, st->base + reg)
>
> @@ -185,18 +210,30 @@ struct at91_adc_state {
> };
>
> static const struct iio_chan_spec at91_adc_channels[] = {
> - AT91_SAMA5D2_CHAN(0, 0x50),
> - AT91_SAMA5D2_CHAN(1, 0x54),
> - AT91_SAMA5D2_CHAN(2, 0x58),
> - AT91_SAMA5D2_CHAN(3, 0x5c),
> - AT91_SAMA5D2_CHAN(4, 0x60),
> - AT91_SAMA5D2_CHAN(5, 0x64),
> - AT91_SAMA5D2_CHAN(6, 0x68),
> - AT91_SAMA5D2_CHAN(7, 0x6c),
> - AT91_SAMA5D2_CHAN(8, 0x70),
> - AT91_SAMA5D2_CHAN(9, 0x74),
> - AT91_SAMA5D2_CHAN(10, 0x78),
> - AT91_SAMA5D2_CHAN(11, 0x7c),
> + AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(0, 0x50),
> + AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(1, 0x54),
> + AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(2, 0x58),
> + AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(3, 0x5c),
> + AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(4, 0x60),
> + AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(5, 0x64),
> + AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(6, 0x68),
> + AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(7, 0x6c),
> + AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(8, 0x70),
> + AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(9, 0x74),
> + AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(10, 0x78),
> + AT91_SAMA5D2_UNSIGNED_VOLTAGE_CHANNEL(11, 0x7c),
> + AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(0, 0x50),
> + AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(1, 0x54),
> + AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(2, 0x58),
> + AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(3, 0x5c),
> + AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(4, 0x60),
> + AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(5, 0x64),
> + AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(6, 0x68),
> + AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(7, 0x6c),
> + AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(8, 0x70),
> + AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(9, 0x74),
> + AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(10, 0x78),
> + AT91_SAMA5D2_SIGNED_VOLTAGE_CHANNEL(11, 0x7c),
> };
>
> static unsigned at91_adc_startup_time(unsigned startup_time_min,
> @@ -278,6 +315,7 @@ static int at91_adc_read_raw(struct iio_dev *indio_dev,
> int *val, int *val2, long mask)
> {
> struct at91_adc_state *st = iio_priv(indio_dev);
> + u32 emr;
> int ret;
>
> switch (mask) {
> @@ -286,6 +324,19 @@ static int at91_adc_read_raw(struct iio_dev *indio_dev,
>
> st->chan = chan;
>
> + /* Read EMR register and clear 'sign mode' field */
> + emr = at91_adc_readl(st, AT91_SAMA5D2_EMR)
> + & AT91_SAMA5D2_EMR_SIGNMODE(0);
> + /*
> + * Check if the user requested a conversion on a signed or
> + * unsigned channel.
> + */
> + if (chan->scan_type.sign == 's')
> + emr |= AT91_SAMA5D2_EMR_SIGNMODE(AT91_SAMA5D2_EMR_ALL_SIGNED);
> + else
> + emr |= AT91_SAMA5D2_EMR_SIGNMODE(AT91_SAMA5D2_EMR_ALL_UNSIGNED);
> +
> + at91_adc_writel(st, AT91_SAMA5D2_EMR, emr);
> at91_adc_writel(st, AT91_SAMA5D2_CHER, BIT(chan->channel));
> at91_adc_writel(st, AT91_SAMA5D2_IER, BIT(chan->channel));
> at91_adc_writel(st, AT91_SAMA5D2_CR, AT91_SAMA5D2_CR_START);
> @@ -298,6 +349,8 @@ static int at91_adc_read_raw(struct iio_dev *indio_dev,
>
> if (ret > 0) {
> *val = st->conversion_value;
> + if (chan->scan_type.sign == 's')
> + *val = sign_extend32(*val, 11);
> ret = IIO_VAL_INT;
> st->conversion_done = false;
> }
>
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2016-03-05 15:16 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-03-03 16:09 [PATCH 0/3] iio:adc:at91-sama5d2: add support for signed conversion Ludovic Desroches
2016-03-03 16:09 ` [PATCH 1/3] iio:adc:at91-sama5d2: fix typo Ludovic Desroches
2016-03-05 15:02 ` Jonathan Cameron
2016-03-03 16:09 ` [PATCH 2/3] iio:adc:at91-sama5d2: fix identation Ludovic Desroches
2016-03-05 15:03 ` Jonathan Cameron
2016-03-03 16:09 ` [PATCH 3/3] iio:adc:at91-sama5d2: add support for signed conversion Ludovic Desroches
2016-03-05 15:16 ` Jonathan Cameron
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