2017-04-19 08:22:40

by Eugen Hristev

[permalink] [raw]
Subject: [PATCH 0/3] iio: adc: sama5d2_adc hw triggers and buffers

This patch implements the hardware triggers support and
buffer management for sama5d2.
The DT modifications ( [PATCH 1/3] ARM: dts: at91: sama5d2_xplained:
enable ADTRG pin) are for demonstration purposes of the feature,
setting the pinctrl for the ADC hw trigger pin,should go through at91
maintainers.
I also increased the buffer size for the trigger name in the generic_buffer
application to cope with longer names and avoid stack smashing problem.
This is in patch [PATCH 3/3] iio: tools: generic_buffer: increase trigger length


Eugen Hristev (3):
ARM: dts: at91: sama5d2_xplained: enable ADTRG pin
iio: adc: at91-sama5d2_adc: add hw trigger and buffer support
iio: tools: generic_buffer: increase trigger length

arch/arm/boot/dts/at91-sama5d2_xplained.dts | 16 ++-
drivers/iio/adc/at91-sama5d2_adc.c | 208 +++++++++++++++++++++++++++-
tools/iio/iio_utils.h | 2 +-
3 files changed, 220 insertions(+), 6 deletions(-)

--
2.7.4


2017-04-19 08:23:01

by Eugen Hristev

[permalink] [raw]
Subject: [PATCH 3/3] iio: tools: generic_buffer: increase trigger length

Increased trigger length to 50 in order to cope with trigger names like
fc030000.adc-dev0-external-rising

Signed-off-by: Eugen Hristev <[email protected]>
---
tools/iio/iio_utils.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/iio/iio_utils.h b/tools/iio/iio_utils.h
index 780f201..9d59771 100644
--- a/tools/iio/iio_utils.h
+++ b/tools/iio/iio_utils.h
@@ -13,7 +13,7 @@
#include <stdint.h>

/* Made up value to limit allocation sizes */
-#define IIO_MAX_NAME_LENGTH 30
+#define IIO_MAX_NAME_LENGTH 50

#define FORMAT_SCAN_ELEMENTS_DIR "%s/scan_elements"
#define FORMAT_TYPE_FILE "%s_type"
--
2.7.4

2017-04-19 08:23:00

by Eugen Hristev

[permalink] [raw]
Subject: [PATCH 2/3] iio: adc: at91-sama5d2_adc: add hw trigger and buffer support

Added support for the external hardware trigger on pin ADTRG,
integrated the three possible edge triggers into the subsystem
and created buffer management for data retrieval

Signed-off-by: Eugen Hristev <[email protected]>
---
drivers/iio/adc/at91-sama5d2_adc.c | 207 ++++++++++++++++++++++++++++++++++++-
1 file changed, 204 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
index e10dca3..09a8c3d 100644
--- a/drivers/iio/adc/at91-sama5d2_adc.c
+++ b/drivers/iio/adc/at91-sama5d2_adc.c
@@ -23,8 +23,15 @@
#include <linux/platform_device.h>
#include <linux/sched.h>
#include <linux/wait.h>
+#include <linux/slab.h>
+
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
#include <linux/regulator/consumer.h>

/* Control Register */
@@ -132,6 +139,17 @@
#define AT91_SAMA5D2_PRESSR 0xbc
/* Trigger Register */
#define AT91_SAMA5D2_TRGR 0xc0
+/* Mask for TRGMOD field of TRGR register */
+#define AT91_SAMA5D2_TRGR_TRGMOD_MASK GENMASK(2, 0)
+/* No trigger, only software trigger can start conversions */
+#define AT91_SAMA5D2_TRGR_TRGMOD_NO_TRIGGER 0
+/* Trigger Mode external trigger rising edge */
+#define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_RISE 1
+/* Trigger Mode external trigger falling edge */
+#define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_FALL 2
+/* Trigger Mode external trigger any edge */
+#define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_ANY 3
+
/* Correction Select Register */
#define AT91_SAMA5D2_COSR 0xd0
/* Correction Value Register */
@@ -145,14 +163,20 @@
/* Version Register */
#define AT91_SAMA5D2_VERSION 0xfc

+#define AT91_SAMA5D2_HW_TRIG_CNT 3
+#define AT91_SAMA5D2_SINGLE_CHAN_CNT 12
+#define AT91_SAMA5D2_DIFF_CHAN_CNT 6
+
#define AT91_SAMA5D2_CHAN_SINGLE(num, addr) \
{ \
.type = IIO_VOLTAGE, \
.channel = num, \
.address = addr, \
+ .scan_index = num, \
.scan_type = { \
.sign = 'u', \
.realbits = 12, \
+ .storagebits = 16, \
}, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
@@ -168,9 +192,11 @@
.channel = num, \
.channel2 = num2, \
.address = addr, \
+ .scan_index = num + AT91_SAMA5D2_SINGLE_CHAN_CNT, \
.scan_type = { \
.sign = 's', \
.realbits = 12, \
+ .storagebits = 16, \
}, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
@@ -188,18 +214,26 @@ struct at91_adc_soc_info {
unsigned max_sample_rate;
};

+struct at91_adc_trigger {
+ char *name;
+ unsigned int trgmod_value;
+};
+
struct at91_adc_state {
void __iomem *base;
int irq;
struct clk *per_clk;
struct regulator *reg;
struct regulator *vref;
+ u16 *buffer;
int vref_uv;
const struct iio_chan_spec *chan;
bool conversion_done;
u32 conversion_value;
struct at91_adc_soc_info soc_info;
wait_queue_head_t wq_data_available;
+ struct iio_trigger **trig;
+ const struct at91_adc_trigger *trigger_list;
/*
* lock to prevent concurrent 'single conversion' requests through
* sysfs.
@@ -207,6 +241,21 @@ struct at91_adc_state {
struct mutex lock;
};

+static const struct at91_adc_trigger at91_adc_trigger_list[] = {
+ {
+ .name = "external-rising",
+ .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_RISE,
+ },
+ {
+ .name = "external-falling",
+ .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_FALL,
+ },
+ {
+ .name = "external-any",
+ .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_ANY,
+ },
+};
+
static const struct iio_chan_spec at91_adc_channels[] = {
AT91_SAMA5D2_CHAN_SINGLE(0, 0x50),
AT91_SAMA5D2_CHAN_SINGLE(1, 0x54),
@@ -226,8 +275,141 @@ static const struct iio_chan_spec at91_adc_channels[] = {
AT91_SAMA5D2_CHAN_DIFF(6, 7, 0x68),
AT91_SAMA5D2_CHAN_DIFF(8, 9, 0x70),
AT91_SAMA5D2_CHAN_DIFF(10, 11, 0x78),
+ IIO_CHAN_SOFT_TIMESTAMP(AT91_SAMA5D2_SINGLE_CHAN_CNT
+ + AT91_SAMA5D2_DIFF_CHAN_CNT + 1),
};

+static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
+{
+ struct iio_dev *indio = iio_trigger_get_drvdata(trig);
+ struct at91_adc_state *st = iio_priv(indio);
+ u32 status = at91_adc_readl(st, AT91_SAMA5D2_TRGR);
+ u8 bit;
+ int i;
+
+ /* clear TRGMOD */
+ status &= ~AT91_SAMA5D2_TRGR_TRGMOD_MASK;
+
+ /* if we are disabling the trigger, it's enough to clear TRGMOD */
+ if (!state) {
+ at91_adc_writel(st, AT91_SAMA5D2_TRGR, status);
+ kfree(st->buffer);
+ return 0;
+ }
+
+ st->buffer = kmalloc(indio->scan_bytes, GFP_KERNEL);
+ if (!st->buffer)
+ return -ENOMEM;
+
+ for (i = 0; i < AT91_SAMA5D2_HW_TRIG_CNT; i++) {
+ if (!strstr(trig->name, st->trigger_list[i].name)) {
+ status |= st->trigger_list[i].trgmod_value;
+ break;
+ }
+ }
+
+ /* setup hw trigger */
+ at91_adc_writel(st, AT91_SAMA5D2_TRGR, status);
+
+ for_each_set_bit(bit, indio->active_scan_mask, indio->num_channels) {
+ struct iio_chan_spec const *chan = indio->channels + bit;
+
+ at91_adc_writel(st, AT91_SAMA5D2_CHER, BIT(chan->channel));
+ at91_adc_writel(st, AT91_SAMA5D2_IER, BIT(chan->channel));
+ }
+
+ return 0;
+}
+
+static const struct iio_trigger_ops at91_adc_trigger_ops = {
+ .owner = THIS_MODULE,
+ .set_trigger_state = &at91_adc_configure_trigger,
+};
+
+static struct iio_trigger *at91_adc_allocate_trigger(struct iio_dev *indio,
+ char *trigger_name)
+{
+ struct iio_trigger *trig;
+ int ret;
+
+ trig = devm_iio_trigger_alloc(&indio->dev, "%s-dev%d-%s", indio->name,
+ indio->id, trigger_name);
+ if (!trig)
+ return NULL;
+
+ trig->dev.parent = indio->dev.parent;
+ iio_trigger_set_drvdata(trig, indio);
+ trig->ops = &at91_adc_trigger_ops;
+
+ ret = devm_iio_trigger_register(&indio->dev, trig);
+
+ if (ret)
+ return NULL;
+
+ return trig;
+}
+
+static int at91_adc_trigger_init(struct iio_dev *indio)
+{
+ struct at91_adc_state *st = iio_priv(indio);
+ int i;
+
+ st->trig = devm_kzalloc(&indio->dev,
+ AT91_SAMA5D2_HW_TRIG_CNT * sizeof(*st->trig),
+ GFP_KERNEL);
+
+ if (!st->trig) {
+ dev_err(&indio->dev, "could not allocate trig list memory\n");
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < AT91_SAMA5D2_HW_TRIG_CNT; i++) {
+ st->trig[i] = at91_adc_allocate_trigger(indio,
+ st->trigger_list[i].name);
+ if (!st->trig[i]) {
+ dev_err(&indio->dev,
+ "could not allocate trigger %d\n", i);
+ return -ENOMEM;
+ }
+ }
+
+ return 0;
+}
+
+static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio = pf->indio_dev;
+ struct at91_adc_state *st = iio_priv(indio);
+ int i = 0;
+ u8 bit;
+
+ for_each_set_bit(bit, indio->active_scan_mask, indio->num_channels) {
+ struct iio_chan_spec const *chan = indio->channels + bit;
+
+ st->buffer[i] = at91_adc_readl(st, chan->address);
+ i++;
+ }
+
+ iio_push_to_buffers_with_timestamp(indio, st->buffer, pf->timestamp);
+
+ iio_trigger_notify_done(indio->trig);
+
+ /* Needed to ACK the DRDY interruption */
+ at91_adc_readl(st, AT91_SAMA5D2_LCDR);
+
+ enable_irq(st->irq);
+
+ return IRQ_HANDLED;
+}
+
+static int at91_adc_buffer_init(struct iio_dev *indio)
+{
+ return devm_iio_triggered_buffer_setup(&indio->dev, indio,
+ &iio_pollfunc_store_time,
+ &at91_adc_trigger_handler, NULL);
+}
+
static unsigned at91_adc_startup_time(unsigned startup_time_min,
unsigned adc_clk_khz)
{
@@ -293,14 +475,19 @@ static irqreturn_t at91_adc_interrupt(int irq, void *private)
u32 status = at91_adc_readl(st, AT91_SAMA5D2_ISR);
u32 imr = at91_adc_readl(st, AT91_SAMA5D2_IMR);

- if (status & imr) {
+ if (!(status & imr))
+ return IRQ_NONE;
+
+ if (iio_buffer_enabled(indio)) {
+ disable_irq_nosync(irq);
+ iio_trigger_poll(indio->trig);
+ } else {
st->conversion_value = at91_adc_readl(st, st->chan->address);
st->conversion_done = true;
wake_up_interruptible(&st->wq_data_available);
- return IRQ_HANDLED;
}

- return IRQ_NONE;
+ return IRQ_HANDLED;
}

static int at91_adc_read_raw(struct iio_dev *indio_dev,
@@ -406,6 +593,8 @@ static int at91_adc_probe(struct platform_device *pdev)

st = iio_priv(indio_dev);

+ st->trigger_list = at91_adc_trigger_list;
+
ret = of_property_read_u32(pdev->dev.of_node,
"atmel,min-sample-rate-hz",
&st->soc_info.min_sample_rate);
@@ -499,6 +688,18 @@ static int at91_adc_probe(struct platform_device *pdev)

platform_set_drvdata(pdev, indio_dev);

+ ret = at91_adc_buffer_init(indio_dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "couldn't initialize the buffer.\n");
+ goto per_clk_disable_unprepare;
+ }
+
+ ret = at91_adc_trigger_init(indio_dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "couldn't setup the triggers.\n");
+ goto per_clk_disable_unprepare;
+ }
+
ret = iio_device_register(indio_dev);
if (ret < 0)
goto per_clk_disable_unprepare;
--
2.7.4

2017-04-19 08:22:58

by Eugen Hristev

[permalink] [raw]
Subject: [PATCH 1/3] ARM: dts: at91: sama5d2_xplained: enable ADTRG pin

Enable pinctrl for ADTRG pin (PD31) for ADC hardware trigger support.

Signed-off-by: Eugen Hristev <[email protected]>
---
arch/arm/boot/dts/at91-sama5d2_xplained.dts | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/at91-sama5d2_xplained.dts b/arch/arm/boot/dts/at91-sama5d2_xplained.dts
index 0bef9e0..04754b1 100644
--- a/arch/arm/boot/dts/at91-sama5d2_xplained.dts
+++ b/arch/arm/boot/dts/at91-sama5d2_xplained.dts
@@ -303,7 +303,7 @@
vddana-supply = <&vdd_3v3_lp_reg>;
vref-supply = <&vdd_3v3_lp_reg>;
pinctrl-names = "default";
- pinctrl-0 = <&pinctrl_adc_default>;
+ pinctrl-0 = <&pinctrl_adc_default &pinctrl_adtrg_default>;
status = "okay";
};

@@ -322,6 +322,20 @@
bias-disable;
};

+ /*
+ * The ADTRG pin can work on any edge type.
+ * In here it's being pulled up, so need to
+ * connect it to ground to get an edge e.g.
+ * Trigger can be configured on falling, rise
+ * or any edge, and the pull-up can be changed
+ * to pull-down or left floating according to
+ * needs.
+ */
+ pinctrl_adtrg_default: adtrg_default {
+ pinmux = <PIN_PD31__ADTRG>;
+ bias-pull-up;
+ };
+
pinctrl_charger_chglev: charger_chglev {
pinmux = <PIN_PA12__GPIO>;
bias-disable;
--
2.7.4

2017-04-20 16:07:00

by Daniel Baluta

[permalink] [raw]
Subject: Re: [PATCH 3/3] iio: tools: generic_buffer: increase trigger length

On Wed, Apr 19, 2017 at 11:20 AM, Eugen Hristev
<[email protected]> wrote:
> Increased trigger length to 50 in order to cope with trigger names like
> fc030000.adc-dev0-external-rising
>
> Signed-off-by: Eugen Hristev <[email protected]>
> ---
> tools/iio/iio_utils.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/iio/iio_utils.h b/tools/iio/iio_utils.h
> index 780f201..9d59771 100644
> --- a/tools/iio/iio_utils.h
> +++ b/tools/iio/iio_utils.h
> @@ -13,7 +13,7 @@
> #include <stdint.h>
>
> /* Made up value to limit allocation sizes */
> -#define IIO_MAX_NAME_LENGTH 30
> +#define IIO_MAX_NAME_LENGTH 50

While at it, lets be brave and set it to 64. :)

Daniel.

2017-04-24 09:05:37

by Ludovic Desroches

[permalink] [raw]
Subject: Re: [PATCH 1/3] ARM: dts: at91: sama5d2_xplained: enable ADTRG pin

On Wed, Apr 19, 2017 at 11:20:43AM +0300, Eugen Hristev wrote:
> Enable pinctrl for ADTRG pin (PD31) for ADC hardware trigger support.
>
> Signed-off-by: Eugen Hristev <[email protected]>
Acked-by: Ludovic Desroches <[email protected]>

> ---
> arch/arm/boot/dts/at91-sama5d2_xplained.dts | 16 +++++++++++++++-
> 1 file changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/boot/dts/at91-sama5d2_xplained.dts b/arch/arm/boot/dts/at91-sama5d2_xplained.dts
> index 0bef9e0..04754b1 100644
> --- a/arch/arm/boot/dts/at91-sama5d2_xplained.dts
> +++ b/arch/arm/boot/dts/at91-sama5d2_xplained.dts
> @@ -303,7 +303,7 @@
> vddana-supply = <&vdd_3v3_lp_reg>;
> vref-supply = <&vdd_3v3_lp_reg>;
> pinctrl-names = "default";
> - pinctrl-0 = <&pinctrl_adc_default>;
> + pinctrl-0 = <&pinctrl_adc_default &pinctrl_adtrg_default>;
> status = "okay";
> };
>
> @@ -322,6 +322,20 @@
> bias-disable;
> };
>
> + /*
> + * The ADTRG pin can work on any edge type.
> + * In here it's being pulled up, so need to
> + * connect it to ground to get an edge e.g.
> + * Trigger can be configured on falling, rise
> + * or any edge, and the pull-up can be changed
> + * to pull-down or left floating according to
> + * needs.
> + */
> + pinctrl_adtrg_default: adtrg_default {
> + pinmux = <PIN_PD31__ADTRG>;
> + bias-pull-up;
> + };
> +
> pinctrl_charger_chglev: charger_chglev {
> pinmux = <PIN_PA12__GPIO>;
> bias-disable;
> --
> 2.7.4
>

2017-04-24 09:06:51

by Ludovic Desroches

[permalink] [raw]
Subject: Re: [PATCH 2/3] iio: adc: at91-sama5d2_adc: add hw trigger and buffer support

On Wed, Apr 19, 2017 at 11:20:44AM +0300, Eugen Hristev wrote:
> Added support for the external hardware trigger on pin ADTRG,
> integrated the three possible edge triggers into the subsystem
> and created buffer management for data retrieval
>
> Signed-off-by: Eugen Hristev <[email protected]>
Acked-by: Ludovic Desroches <[email protected]>

> ---
> drivers/iio/adc/at91-sama5d2_adc.c | 207 ++++++++++++++++++++++++++++++++++++-
> 1 file changed, 204 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
> index e10dca3..09a8c3d 100644
> --- a/drivers/iio/adc/at91-sama5d2_adc.c
> +++ b/drivers/iio/adc/at91-sama5d2_adc.c
> @@ -23,8 +23,15 @@
> #include <linux/platform_device.h>
> #include <linux/sched.h>
> #include <linux/wait.h>
> +#include <linux/slab.h>
> +
> #include <linux/iio/iio.h>
> #include <linux/iio/sysfs.h>
> +#include <linux/iio/buffer.h>
> +#include <linux/iio/trigger.h>
> +#include <linux/iio/trigger_consumer.h>
> +#include <linux/iio/triggered_buffer.h>
> +
> #include <linux/regulator/consumer.h>
>
> /* Control Register */
> @@ -132,6 +139,17 @@
> #define AT91_SAMA5D2_PRESSR 0xbc
> /* Trigger Register */
> #define AT91_SAMA5D2_TRGR 0xc0
> +/* Mask for TRGMOD field of TRGR register */
> +#define AT91_SAMA5D2_TRGR_TRGMOD_MASK GENMASK(2, 0)
> +/* No trigger, only software trigger can start conversions */
> +#define AT91_SAMA5D2_TRGR_TRGMOD_NO_TRIGGER 0
> +/* Trigger Mode external trigger rising edge */
> +#define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_RISE 1
> +/* Trigger Mode external trigger falling edge */
> +#define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_FALL 2
> +/* Trigger Mode external trigger any edge */
> +#define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_ANY 3
> +
> /* Correction Select Register */
> #define AT91_SAMA5D2_COSR 0xd0
> /* Correction Value Register */
> @@ -145,14 +163,20 @@
> /* Version Register */
> #define AT91_SAMA5D2_VERSION 0xfc
>
> +#define AT91_SAMA5D2_HW_TRIG_CNT 3
> +#define AT91_SAMA5D2_SINGLE_CHAN_CNT 12
> +#define AT91_SAMA5D2_DIFF_CHAN_CNT 6
> +
> #define AT91_SAMA5D2_CHAN_SINGLE(num, addr) \
> { \
> .type = IIO_VOLTAGE, \
> .channel = num, \
> .address = addr, \
> + .scan_index = num, \
> .scan_type = { \
> .sign = 'u', \
> .realbits = 12, \
> + .storagebits = 16, \
> }, \
> .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
> @@ -168,9 +192,11 @@
> .channel = num, \
> .channel2 = num2, \
> .address = addr, \
> + .scan_index = num + AT91_SAMA5D2_SINGLE_CHAN_CNT, \
> .scan_type = { \
> .sign = 's', \
> .realbits = 12, \
> + .storagebits = 16, \
> }, \
> .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
> @@ -188,18 +214,26 @@ struct at91_adc_soc_info {
> unsigned max_sample_rate;
> };
>
> +struct at91_adc_trigger {
> + char *name;
> + unsigned int trgmod_value;
> +};
> +
> struct at91_adc_state {
> void __iomem *base;
> int irq;
> struct clk *per_clk;
> struct regulator *reg;
> struct regulator *vref;
> + u16 *buffer;
> int vref_uv;
> const struct iio_chan_spec *chan;
> bool conversion_done;
> u32 conversion_value;
> struct at91_adc_soc_info soc_info;
> wait_queue_head_t wq_data_available;
> + struct iio_trigger **trig;
> + const struct at91_adc_trigger *trigger_list;
> /*
> * lock to prevent concurrent 'single conversion' requests through
> * sysfs.
> @@ -207,6 +241,21 @@ struct at91_adc_state {
> struct mutex lock;
> };
>
> +static const struct at91_adc_trigger at91_adc_trigger_list[] = {
> + {
> + .name = "external-rising",
> + .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_RISE,
> + },
> + {
> + .name = "external-falling",
> + .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_FALL,
> + },
> + {
> + .name = "external-any",
> + .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_ANY,
> + },
> +};
> +
> static const struct iio_chan_spec at91_adc_channels[] = {
> AT91_SAMA5D2_CHAN_SINGLE(0, 0x50),
> AT91_SAMA5D2_CHAN_SINGLE(1, 0x54),
> @@ -226,8 +275,141 @@ static const struct iio_chan_spec at91_adc_channels[] = {
> AT91_SAMA5D2_CHAN_DIFF(6, 7, 0x68),
> AT91_SAMA5D2_CHAN_DIFF(8, 9, 0x70),
> AT91_SAMA5D2_CHAN_DIFF(10, 11, 0x78),
> + IIO_CHAN_SOFT_TIMESTAMP(AT91_SAMA5D2_SINGLE_CHAN_CNT
> + + AT91_SAMA5D2_DIFF_CHAN_CNT + 1),
> };
>
> +static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
> +{
> + struct iio_dev *indio = iio_trigger_get_drvdata(trig);
> + struct at91_adc_state *st = iio_priv(indio);
> + u32 status = at91_adc_readl(st, AT91_SAMA5D2_TRGR);
> + u8 bit;
> + int i;
> +
> + /* clear TRGMOD */
> + status &= ~AT91_SAMA5D2_TRGR_TRGMOD_MASK;
> +
> + /* if we are disabling the trigger, it's enough to clear TRGMOD */
> + if (!state) {
> + at91_adc_writel(st, AT91_SAMA5D2_TRGR, status);
> + kfree(st->buffer);
> + return 0;
> + }
> +
> + st->buffer = kmalloc(indio->scan_bytes, GFP_KERNEL);
> + if (!st->buffer)
> + return -ENOMEM;
> +
> + for (i = 0; i < AT91_SAMA5D2_HW_TRIG_CNT; i++) {
> + if (!strstr(trig->name, st->trigger_list[i].name)) {
> + status |= st->trigger_list[i].trgmod_value;
> + break;
> + }
> + }
> +
> + /* setup hw trigger */
> + at91_adc_writel(st, AT91_SAMA5D2_TRGR, status);
> +
> + for_each_set_bit(bit, indio->active_scan_mask, indio->num_channels) {
> + struct iio_chan_spec const *chan = indio->channels + bit;
> +
> + at91_adc_writel(st, AT91_SAMA5D2_CHER, BIT(chan->channel));
> + at91_adc_writel(st, AT91_SAMA5D2_IER, BIT(chan->channel));
> + }
> +
> + return 0;
> +}
> +
> +static const struct iio_trigger_ops at91_adc_trigger_ops = {
> + .owner = THIS_MODULE,
> + .set_trigger_state = &at91_adc_configure_trigger,
> +};
> +
> +static struct iio_trigger *at91_adc_allocate_trigger(struct iio_dev *indio,
> + char *trigger_name)
> +{
> + struct iio_trigger *trig;
> + int ret;
> +
> + trig = devm_iio_trigger_alloc(&indio->dev, "%s-dev%d-%s", indio->name,
> + indio->id, trigger_name);
> + if (!trig)
> + return NULL;
> +
> + trig->dev.parent = indio->dev.parent;
> + iio_trigger_set_drvdata(trig, indio);
> + trig->ops = &at91_adc_trigger_ops;
> +
> + ret = devm_iio_trigger_register(&indio->dev, trig);
> +
> + if (ret)
> + return NULL;
> +
> + return trig;
> +}
> +
> +static int at91_adc_trigger_init(struct iio_dev *indio)
> +{
> + struct at91_adc_state *st = iio_priv(indio);
> + int i;
> +
> + st->trig = devm_kzalloc(&indio->dev,
> + AT91_SAMA5D2_HW_TRIG_CNT * sizeof(*st->trig),
> + GFP_KERNEL);
> +
> + if (!st->trig) {
> + dev_err(&indio->dev, "could not allocate trig list memory\n");
> + return -ENOMEM;
> + }
> +
> + for (i = 0; i < AT91_SAMA5D2_HW_TRIG_CNT; i++) {
> + st->trig[i] = at91_adc_allocate_trigger(indio,
> + st->trigger_list[i].name);
> + if (!st->trig[i]) {
> + dev_err(&indio->dev,
> + "could not allocate trigger %d\n", i);
> + return -ENOMEM;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
> +{
> + struct iio_poll_func *pf = p;
> + struct iio_dev *indio = pf->indio_dev;
> + struct at91_adc_state *st = iio_priv(indio);
> + int i = 0;
> + u8 bit;
> +
> + for_each_set_bit(bit, indio->active_scan_mask, indio->num_channels) {
> + struct iio_chan_spec const *chan = indio->channels + bit;
> +
> + st->buffer[i] = at91_adc_readl(st, chan->address);
> + i++;
> + }
> +
> + iio_push_to_buffers_with_timestamp(indio, st->buffer, pf->timestamp);
> +
> + iio_trigger_notify_done(indio->trig);
> +
> + /* Needed to ACK the DRDY interruption */
> + at91_adc_readl(st, AT91_SAMA5D2_LCDR);
> +
> + enable_irq(st->irq);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int at91_adc_buffer_init(struct iio_dev *indio)
> +{
> + return devm_iio_triggered_buffer_setup(&indio->dev, indio,
> + &iio_pollfunc_store_time,
> + &at91_adc_trigger_handler, NULL);
> +}
> +
> static unsigned at91_adc_startup_time(unsigned startup_time_min,
> unsigned adc_clk_khz)
> {
> @@ -293,14 +475,19 @@ static irqreturn_t at91_adc_interrupt(int irq, void *private)
> u32 status = at91_adc_readl(st, AT91_SAMA5D2_ISR);
> u32 imr = at91_adc_readl(st, AT91_SAMA5D2_IMR);
>
> - if (status & imr) {
> + if (!(status & imr))
> + return IRQ_NONE;
> +
> + if (iio_buffer_enabled(indio)) {
> + disable_irq_nosync(irq);
> + iio_trigger_poll(indio->trig);
> + } else {
> st->conversion_value = at91_adc_readl(st, st->chan->address);
> st->conversion_done = true;
> wake_up_interruptible(&st->wq_data_available);
> - return IRQ_HANDLED;
> }
>
> - return IRQ_NONE;
> + return IRQ_HANDLED;
> }
>
> static int at91_adc_read_raw(struct iio_dev *indio_dev,
> @@ -406,6 +593,8 @@ static int at91_adc_probe(struct platform_device *pdev)
>
> st = iio_priv(indio_dev);
>
> + st->trigger_list = at91_adc_trigger_list;
> +
> ret = of_property_read_u32(pdev->dev.of_node,
> "atmel,min-sample-rate-hz",
> &st->soc_info.min_sample_rate);
> @@ -499,6 +688,18 @@ static int at91_adc_probe(struct platform_device *pdev)
>
> platform_set_drvdata(pdev, indio_dev);
>
> + ret = at91_adc_buffer_init(indio_dev);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "couldn't initialize the buffer.\n");
> + goto per_clk_disable_unprepare;
> + }
> +
> + ret = at91_adc_trigger_init(indio_dev);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "couldn't setup the triggers.\n");
> + goto per_clk_disable_unprepare;
> + }
> +
> ret = iio_device_register(indio_dev);
> if (ret < 0)
> goto per_clk_disable_unprepare;
> --
> 2.7.4
>

2017-04-27 05:19:51

by Jonathan Cameron

[permalink] [raw]
Subject: Re: [PATCH 3/3] iio: tools: generic_buffer: increase trigger length

On 19/04/17 09:20, Eugen Hristev wrote:
> Increased trigger length to 50 in order to cope with trigger names like
> fc030000.adc-dev0-external-rising
>
> Signed-off-by: Eugen Hristev <[email protected]>
This is fine (though I'd go bigger as Daniel suggested)
I'll pick it up with the revised series.

thanks,

Jonathan
> ---
> tools/iio/iio_utils.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/iio/iio_utils.h b/tools/iio/iio_utils.h
> index 780f201..9d59771 100644
> --- a/tools/iio/iio_utils.h
> +++ b/tools/iio/iio_utils.h
> @@ -13,7 +13,7 @@
> #include <stdint.h>
>
> /* Made up value to limit allocation sizes */
> -#define IIO_MAX_NAME_LENGTH 30
> +#define IIO_MAX_NAME_LENGTH 50
>
> #define FORMAT_SCAN_ELEMENTS_DIR "%s/scan_elements"
> #define FORMAT_TYPE_FILE "%s_type"
>

2017-04-27 05:19:00

by Jonathan Cameron

[permalink] [raw]
Subject: Re: [PATCH 2/3] iio: adc: at91-sama5d2_adc: add hw trigger and buffer support

On 19/04/17 09:20, Eugen Hristev wrote:
> Added support for the external hardware trigger on pin ADTRG,
> integrated the three possible edge triggers into the subsystem
> and created buffer management for data retrieval
>
> Signed-off-by: Eugen Hristev <[email protected]>
> ---
> drivers/iio/adc/at91-sama5d2_adc.c | 207 ++++++++++++++++++++++++++++++++++++-
> 1 file changed, 204 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
> index e10dca3..09a8c3d 100644
> --- a/drivers/iio/adc/at91-sama5d2_adc.c
> +++ b/drivers/iio/adc/at91-sama5d2_adc.c
> @@ -23,8 +23,15 @@
> #include <linux/platform_device.h>
> #include <linux/sched.h>
> #include <linux/wait.h>
> +#include <linux/slab.h>
> +
> #include <linux/iio/iio.h>
> #include <linux/iio/sysfs.h>
> +#include <linux/iio/buffer.h>
> +#include <linux/iio/trigger.h>
> +#include <linux/iio/trigger_consumer.h>
> +#include <linux/iio/triggered_buffer.h>
> +
> #include <linux/regulator/consumer.h>
>
> /* Control Register */
> @@ -132,6 +139,17 @@
> #define AT91_SAMA5D2_PRESSR 0xbc
> /* Trigger Register */
> #define AT91_SAMA5D2_TRGR 0xc0
> +/* Mask for TRGMOD field of TRGR register */
> +#define AT91_SAMA5D2_TRGR_TRGMOD_MASK GENMASK(2, 0)
> +/* No trigger, only software trigger can start conversions */
> +#define AT91_SAMA5D2_TRGR_TRGMOD_NO_TRIGGER 0
> +/* Trigger Mode external trigger rising edge */
> +#define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_RISE 1
> +/* Trigger Mode external trigger falling edge */
> +#define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_FALL 2
> +/* Trigger Mode external trigger any edge */
> +#define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_ANY 3
> +
> /* Correction Select Register */
> #define AT91_SAMA5D2_COSR 0xd0
> /* Correction Value Register */
> @@ -145,14 +163,20 @@
> /* Version Register */
> #define AT91_SAMA5D2_VERSION 0xfc
>
> +#define AT91_SAMA5D2_HW_TRIG_CNT 3
> +#define AT91_SAMA5D2_SINGLE_CHAN_CNT 12
> +#define AT91_SAMA5D2_DIFF_CHAN_CNT 6
> +
> #define AT91_SAMA5D2_CHAN_SINGLE(num, addr) \
> { \
> .type = IIO_VOLTAGE, \
> .channel = num, \
> .address = addr, \
> + .scan_index = num, \
> .scan_type = { \
> .sign = 'u', \
> .realbits = 12, \
> + .storagebits = 16, \
> }, \
> .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
> @@ -168,9 +192,11 @@
> .channel = num, \
> .channel2 = num2, \
> .address = addr, \
> + .scan_index = num + AT91_SAMA5D2_SINGLE_CHAN_CNT, \
> .scan_type = { \
> .sign = 's', \
> .realbits = 12, \
> + .storagebits = 16, \
> }, \
> .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
> @@ -188,18 +214,26 @@ struct at91_adc_soc_info {
> unsigned max_sample_rate;
> };
>
> +struct at91_adc_trigger {
> + char *name;
> + unsigned int trgmod_value;
> +};
> +
> struct at91_adc_state {
> void __iomem *base;
> int irq;
> struct clk *per_clk;
> struct regulator *reg;
> struct regulator *vref;
> + u16 *buffer;
> int vref_uv;
> const struct iio_chan_spec *chan;
> bool conversion_done;
> u32 conversion_value;
> struct at91_adc_soc_info soc_info;
> wait_queue_head_t wq_data_available;
> + struct iio_trigger **trig;
> + const struct at91_adc_trigger *trigger_list;
> /*
> * lock to prevent concurrent 'single conversion' requests through
> * sysfs.
> @@ -207,6 +241,21 @@ struct at91_adc_state {
> struct mutex lock;
> };
>
> +static const struct at91_adc_trigger at91_adc_trigger_list[] = {
> + {
> + .name = "external-rising",
> + .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_RISE,
> + },
> + {
> + .name = "external-falling",
> + .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_FALL,
> + },
> + {
> + .name = "external-any",
> + .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_ANY,
> + },
> +};
> +
> static const struct iio_chan_spec at91_adc_channels[] = {
> AT91_SAMA5D2_CHAN_SINGLE(0, 0x50),
> AT91_SAMA5D2_CHAN_SINGLE(1, 0x54),
> @@ -226,8 +275,141 @@ static const struct iio_chan_spec at91_adc_channels[] = {
> AT91_SAMA5D2_CHAN_DIFF(6, 7, 0x68),
> AT91_SAMA5D2_CHAN_DIFF(8, 9, 0x70),
> AT91_SAMA5D2_CHAN_DIFF(10, 11, 0x78),
> + IIO_CHAN_SOFT_TIMESTAMP(AT91_SAMA5D2_SINGLE_CHAN_CNT
> + + AT91_SAMA5D2_DIFF_CHAN_CNT + 1),
> };
>
> +static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
> +{
> + struct iio_dev *indio = iio_trigger_get_drvdata(trig);
> + struct at91_adc_state *st = iio_priv(indio);
> + u32 status = at91_adc_readl(st, AT91_SAMA5D2_TRGR);
> + u8 bit;
> + int i;
> +
> + /* clear TRGMOD */
> + status &= ~AT91_SAMA5D2_TRGR_TRGMOD_MASK;
> +
> + /* if we are disabling the trigger, it's enough to clear TRGMOD */
> + if (!state) {
> + at91_adc_writel(st, AT91_SAMA5D2_TRGR, status);
> + kfree(st->buffer);
Would normally expect to see elements related to the buffer in the
preenable callback for the buffer. In this case it might not make
much difference, but that's conceptually where it belongs.
> + return 0;
> + }
> +
> + st->buffer = kmalloc(indio->scan_bytes, GFP_KERNEL);
How big does this get? I'd be tempted to just use a fixed size big
enough to take the maximum possible. Will probably end up more
efficient than allocating it separately. Not to mention slightly
simplified code.
> + if (!st->buffer)
> + return -ENOMEM;
> +
> + for (i = 0; i < AT91_SAMA5D2_HW_TRIG_CNT; i++) {
> + if (!strstr(trig->name, st->trigger_list[i].name)) {
> + status |= st->trigger_list[i].trgmod_value;
> + break;
> + }
> + }
> +
> + /* setup hw trigger */
> + at91_adc_writel(st, AT91_SAMA5D2_TRGR, status);
> +
> + for_each_set_bit(bit, indio->active_scan_mask, indio->num_channels) {
> + struct iio_chan_spec const *chan = indio->channels + bit;
> +
> + at91_adc_writel(st, AT91_SAMA5D2_CHER, BIT(chan->channel));
> + at91_adc_writel(st, AT91_SAMA5D2_IER, BIT(chan->channel));
> + }
> +
> + return 0;
> +}
> +
> +static const struct iio_trigger_ops at91_adc_trigger_ops = {
> + .owner = THIS_MODULE,
> + .set_trigger_state = &at91_adc_configure_trigger,
> +};
> +
> +static struct iio_trigger *at91_adc_allocate_trigger(struct iio_dev *indio,
> + char *trigger_name)
> +{
> + struct iio_trigger *trig;
> + int ret;
> +
> + trig = devm_iio_trigger_alloc(&indio->dev, "%s-dev%d-%s", indio->name,
> + indio->id, trigger_name);
> + if (!trig)
> + return NULL;
> +
> + trig->dev.parent = indio->dev.parent;
> + iio_trigger_set_drvdata(trig, indio);
> + trig->ops = &at91_adc_trigger_ops;
> +
> + ret = devm_iio_trigger_register(&indio->dev, trig);
> +
> + if (ret)
> + return NULL;
> +
> + return trig;
> +}
> +
> +static int at91_adc_trigger_init(struct iio_dev *indio)
> +{
> + struct at91_adc_state *st = iio_priv(indio);
> + int i;
> +
> + st->trig = devm_kzalloc(&indio->dev,
> + AT91_SAMA5D2_HW_TRIG_CNT * sizeof(*st->trig),
> + GFP_KERNEL);
Given it's a fixed sized allocation, why not just make the resulting array
part of st directly?
> +
> + if (!st->trig) {
> + dev_err(&indio->dev, "could not allocate trig list memory\n");
> + return -ENOMEM;
> + }
> +
> + for (i = 0; i < AT91_SAMA5D2_HW_TRIG_CNT; i++) {
> + st->trig[i] = at91_adc_allocate_trigger(indio,
> + st->trigger_list[i].name);
> + if (!st->trig[i]) {
> + dev_err(&indio->dev,
> + "could not allocate trigger %d\n", i);
> + return -ENOMEM;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
> +{
> + struct iio_poll_func *pf = p;
> + struct iio_dev *indio = pf->indio_dev;
> + struct at91_adc_state *st = iio_priv(indio);
> + int i = 0;
> + u8 bit;
> +
> + for_each_set_bit(bit, indio->active_scan_mask, indio->num_channels) {
> + struct iio_chan_spec const *chan = indio->channels + bit;
> +
> + st->buffer[i] = at91_adc_readl(st, chan->address);
> + i++;
> + }
> +
> + iio_push_to_buffers_with_timestamp(indio, st->buffer, pf->timestamp);
> +
> + iio_trigger_notify_done(indio->trig);
> +
> + /* Needed to ACK the DRDY interruption */
> + at91_adc_readl(st, AT91_SAMA5D2_LCDR);
> +
> + enable_irq(st->irq);
Unusual to have to disable the irq until this point. Firstly
if you did need to do this, it should be in the tryreeenable callback.
You haven't restricted this trigger to just this device, so other
drivers could be hanging of it.

Secondly this irq is always defined to be a threaded oneshot irq
so it should be nicely masked anyway.


> +
> + return IRQ_HANDLED;
> +}
> +
> +static int at91_adc_buffer_init(struct iio_dev *indio)
> +{
> + return devm_iio_triggered_buffer_setup(&indio->dev, indio,
> + &iio_pollfunc_store_time,
> + &at91_adc_trigger_handler, NULL);
This particular wrapper doesn't seem to add much over having it
inline. I'd be tempted to drop it but unimportant if you'd rather
keep it.
> +}
> +
> static unsigned at91_adc_startup_time(unsigned startup_time_min,
> unsigned adc_clk_khz)
> {
> @@ -293,14 +475,19 @@ static irqreturn_t at91_adc_interrupt(int irq, void *private)
> u32 status = at91_adc_readl(st, AT91_SAMA5D2_ISR);
> u32 imr = at91_adc_readl(st, AT91_SAMA5D2_IMR);
>
> - if (status & imr) {
> + if (!(status & imr))
> + return IRQ_NONE;
> +
> + if (iio_buffer_enabled(indio)) {
> + disable_irq_nosync(irq);
> + iio_trigger_poll(indio->trig);
> + } else {
> st->conversion_value = at91_adc_readl(st, st->chan->address);
> st->conversion_done = true;
> wake_up_interruptible(&st->wq_data_available);
> - return IRQ_HANDLED;
> }
>
> - return IRQ_NONE;
> + return IRQ_HANDLED;
> }
>
> static int at91_adc_read_raw(struct iio_dev *indio_dev,
> @@ -406,6 +593,8 @@ static int at91_adc_probe(struct platform_device *pdev)
>
> st = iio_priv(indio_dev);
>
> + st->trigger_list = at91_adc_trigger_list;Given it's const, why not just use it directly?
> +
> ret = of_property_read_u32(pdev->dev.of_node,
> "atmel,min-sample-rate-hz",
> &st->soc_info.min_sample_rate);
> @@ -499,6 +688,18 @@ static int at91_adc_probe(struct platform_device *pdev)
>
> platform_set_drvdata(pdev, indio_dev);
>
> + ret = at91_adc_buffer_init(indio_dev);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "couldn't initialize the buffer.\n");
> + goto per_clk_disable_unprepare;
> + }
> +
> + ret = at91_adc_trigger_init(indio_dev);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "couldn't setup the triggers.\n");
> + goto per_clk_disable_unprepare;
> + }
> +
> ret = iio_device_register(indio_dev);
> if (ret < 0)
> goto per_clk_disable_unprepare;
>