From: Simon Xue <[email protected]>
Add the ability to also support access via (triggered) buffers
next to the existing direct mode.
Device in question is the Odroid Go Advance that connects a joystick
to two of the saradc channels for X and Y axis and the new (and still
pending) adc joystick driver of course wants to use triggered buffers
from the iio subsystem.
Signed-off-by: Simon Xue <[email protected]>
[some simplifications and added commit description]
Signed-off-by: Heiko Stuebner <[email protected]>
---
changes in v3:
- split buffer struct into values and timestamp area similar to dln2-adc
and make sure timestamp gets 8-byte aligned - ALIGN uses 4 as it aligns
u16 elements not bytes - hopefully I got it right this time ;-)
changes in v2:
- use devm_iio_triggered_buffer_setup
- calculate data array size from channel number (curtesy of at91-sama5d2_adc)
drivers/iio/adc/Kconfig | 2 +
drivers/iio/adc/rockchip_saradc.c | 146 ++++++++++++++++++++++--------
2 files changed, 112 insertions(+), 36 deletions(-)
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 12bb8b7ca1ff..8d2dd60614c6 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -809,6 +809,8 @@ config ROCKCHIP_SARADC
tristate "Rockchip SARADC driver"
depends on ARCH_ROCKCHIP || (ARM && COMPILE_TEST)
depends on RESET_CONTROLLER
+ select IIO_BUFFER
+ select IIO_TRIGGERED_BUFFER
help
Say yes here to build support for the SARADC found in SoCs from
Rockchip.
diff --git a/drivers/iio/adc/rockchip_saradc.c b/drivers/iio/adc/rockchip_saradc.c
index 582ba047c4a6..0713363a4b43 100644
--- a/drivers/iio/adc/rockchip_saradc.c
+++ b/drivers/iio/adc/rockchip_saradc.c
@@ -15,7 +15,11 @@
#include <linux/delay.h>
#include <linux/reset.h>
#include <linux/regulator/consumer.h>
+#include <linux/iio/buffer.h>
#include <linux/iio/iio.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
#define SARADC_DATA 0x00
@@ -32,9 +36,12 @@
#define SARADC_DLY_PU_SOC_MASK 0x3f
#define SARADC_TIMEOUT msecs_to_jiffies(100)
+#define SARADC_MAX_CHANNELS 6
+
+/* buffer elements are u16, timestamp needs to be 8-byte aligned */
+#define SARADC_BUFFER_NUM_U16 ALIGN(SARADC_MAX_CHANNELS, 4)
struct rockchip_saradc_data {
- int num_bits;
const struct iio_chan_spec *channels;
int num_channels;
unsigned long clk_rate;
@@ -49,8 +56,37 @@ struct rockchip_saradc {
struct reset_control *reset;
const struct rockchip_saradc_data *data;
u16 last_val;
+ const struct iio_chan_spec *last_chan;
};
+static void rockchip_saradc_power_down(struct rockchip_saradc *info)
+{
+ /* Clear irq & power down adc */
+ writel_relaxed(0, info->regs + SARADC_CTRL);
+}
+
+static int rockchip_saradc_conversion(struct rockchip_saradc *info,
+ struct iio_chan_spec const *chan)
+{
+ reinit_completion(&info->completion);
+
+ /* 8 clock periods as delay between power up and start cmd */
+ writel_relaxed(8, info->regs + SARADC_DLY_PU_SOC);
+
+ info->last_chan = chan;
+
+ /* Select the channel to be used and trigger conversion */
+ writel(SARADC_CTRL_POWER_CTRL
+ | (chan->channel & SARADC_CTRL_CHN_MASK)
+ | SARADC_CTRL_IRQ_ENABLE,
+ info->regs + SARADC_CTRL);
+
+ if (!wait_for_completion_timeout(&info->completion, SARADC_TIMEOUT))
+ return -ETIMEDOUT;
+
+ return 0;
+}
+
static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
@@ -62,24 +98,12 @@ static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
case IIO_CHAN_INFO_RAW:
mutex_lock(&indio_dev->mlock);
- reinit_completion(&info->completion);
-
- /* 8 clock periods as delay between power up and start cmd */
- writel_relaxed(8, info->regs + SARADC_DLY_PU_SOC);
-
- /* Select the channel to be used and trigger conversion */
- writel(SARADC_CTRL_POWER_CTRL
- | (chan->channel & SARADC_CTRL_CHN_MASK)
- | SARADC_CTRL_IRQ_ENABLE,
- info->regs + SARADC_CTRL);
-
- if (!wait_for_completion_timeout(&info->completion,
- SARADC_TIMEOUT)) {
- writel_relaxed(0, info->regs + SARADC_CTRL);
+ ret = rockchip_saradc_conversion(info, chan);
+ if (ret) {
+ rockchip_saradc_power_down(info);
mutex_unlock(&indio_dev->mlock);
- return -ETIMEDOUT;
+ return ret;
}
-
*val = info->last_val;
mutex_unlock(&indio_dev->mlock);
return IIO_VAL_INT;
@@ -91,7 +115,7 @@ static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
}
*val = ret / 1000;
- *val2 = info->data->num_bits;
+ *val2 = chan->scan_type.realbits;
return IIO_VAL_FRACTIONAL_LOG2;
default:
return -EINVAL;
@@ -104,10 +128,9 @@ static irqreturn_t rockchip_saradc_isr(int irq, void *dev_id)
/* Read value */
info->last_val = readl_relaxed(info->regs + SARADC_DATA);
- info->last_val &= GENMASK(info->data->num_bits - 1, 0);
+ info->last_val &= GENMASK(info->last_chan->scan_type.realbits - 1, 0);
- /* Clear irq & power down adc */
- writel_relaxed(0, info->regs + SARADC_CTRL);
+ rockchip_saradc_power_down(info);
complete(&info->completion);
@@ -118,51 +141,55 @@ static const struct iio_info rockchip_saradc_iio_info = {
.read_raw = rockchip_saradc_read_raw,
};
-#define ADC_CHANNEL(_index, _id) { \
+#define ADC_CHANNEL(_index, _id, _res) { \
.type = IIO_VOLTAGE, \
.indexed = 1, \
.channel = _index, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
.datasheet_name = _id, \
+ .scan_index = _index, \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = _res, \
+ .storagebits = 16, \
+ .endianness = IIO_LE, \
+ }, \
}
static const struct iio_chan_spec rockchip_saradc_iio_channels[] = {
- ADC_CHANNEL(0, "adc0"),
- ADC_CHANNEL(1, "adc1"),
- ADC_CHANNEL(2, "adc2"),
+ ADC_CHANNEL(0, "adc0", 10),
+ ADC_CHANNEL(1, "adc1", 10),
+ ADC_CHANNEL(2, "adc2", 10),
};
static const struct rockchip_saradc_data saradc_data = {
- .num_bits = 10,
.channels = rockchip_saradc_iio_channels,
.num_channels = ARRAY_SIZE(rockchip_saradc_iio_channels),
.clk_rate = 1000000,
};
static const struct iio_chan_spec rockchip_rk3066_tsadc_iio_channels[] = {
- ADC_CHANNEL(0, "adc0"),
- ADC_CHANNEL(1, "adc1"),
+ ADC_CHANNEL(0, "adc0", 12),
+ ADC_CHANNEL(1, "adc1", 12),
};
static const struct rockchip_saradc_data rk3066_tsadc_data = {
- .num_bits = 12,
.channels = rockchip_rk3066_tsadc_iio_channels,
.num_channels = ARRAY_SIZE(rockchip_rk3066_tsadc_iio_channels),
.clk_rate = 50000,
};
static const struct iio_chan_spec rockchip_rk3399_saradc_iio_channels[] = {
- ADC_CHANNEL(0, "adc0"),
- ADC_CHANNEL(1, "adc1"),
- ADC_CHANNEL(2, "adc2"),
- ADC_CHANNEL(3, "adc3"),
- ADC_CHANNEL(4, "adc4"),
- ADC_CHANNEL(5, "adc5"),
+ ADC_CHANNEL(0, "adc0", 10),
+ ADC_CHANNEL(1, "adc1", 10),
+ ADC_CHANNEL(2, "adc2", 10),
+ ADC_CHANNEL(3, "adc3", 10),
+ ADC_CHANNEL(4, "adc4", 10),
+ ADC_CHANNEL(5, "adc5", 10),
};
static const struct rockchip_saradc_data rk3399_saradc_data = {
- .num_bits = 10,
.channels = rockchip_rk3399_saradc_iio_channels,
.num_channels = ARRAY_SIZE(rockchip_rk3399_saradc_iio_channels),
.clk_rate = 1000000,
@@ -193,6 +220,42 @@ static void rockchip_saradc_reset_controller(struct reset_control *reset)
reset_control_deassert(reset);
}
+static irqreturn_t rockchip_saradc_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *i_dev = pf->indio_dev;
+ struct rockchip_saradc *info = iio_priv(i_dev);
+ struct {
+ u16 values[SARADC_BUFFER_NUM_U16];
+ int64_t timestamp;
+ } data;
+ int ret;
+ int i, j = 0;
+
+ mutex_lock(&i_dev->mlock);
+
+ for_each_set_bit(i, i_dev->active_scan_mask, i_dev->masklength) {
+ const struct iio_chan_spec *chan = &i_dev->channels[i];
+
+ ret = rockchip_saradc_conversion(info, chan);
+ if (ret) {
+ rockchip_saradc_power_down(info);
+ goto out;
+ }
+
+ data.values[j] = info->last_val;
+ j++;
+ }
+
+ iio_push_to_buffers_with_timestamp(i_dev, &data, iio_get_time_ns(i_dev));
+out:
+ mutex_unlock(&i_dev->mlock);
+
+ iio_trigger_notify_done(i_dev->trig);
+
+ return IRQ_HANDLED;
+}
+
static int rockchip_saradc_probe(struct platform_device *pdev)
{
struct rockchip_saradc *info = NULL;
@@ -221,6 +284,11 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
info->data = match->data;
+ if (info->data->num_channels > SARADC_MAX_CHANNELS) {
+ dev_err(&pdev->dev, "max channels exceeded");
+ return -EINVAL;
+ }
+
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
info->regs = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(info->regs))
@@ -315,6 +383,12 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
indio_dev->channels = info->data->channels;
indio_dev->num_channels = info->data->num_channels;
+ ret = devm_iio_triggered_buffer_setup(&indio_dev->dev, indio_dev, NULL,
+ rockchip_saradc_trigger_handler,
+ NULL);
+ if (ret)
+ goto err_clk;
+
ret = iio_device_register(indio_dev);
if (ret)
goto err_clk;
--
2.24.1
On Mon, 13 Apr 2020 00:42:51 +0200
Heiko Stuebner <[email protected]> wrote:
> From: Simon Xue <[email protected]>
>
> Add the ability to also support access via (triggered) buffers
> next to the existing direct mode.
>
> Device in question is the Odroid Go Advance that connects a joystick
> to two of the saradc channels for X and Y axis and the new (and still
> pending) adc joystick driver of course wants to use triggered buffers
> from the iio subsystem.
>
> Signed-off-by: Simon Xue <[email protected]>
> [some simplifications and added commit description]
> Signed-off-by: Heiko Stuebner <[email protected]>
Comments inline.
The issue with mixing managed and unmanaged allocations needs tidying up.
Sorry if I missed that one before; I probably didn't open up the current
driver to sanity check it :(
Jonathan
> ---
> changes in v3:
> - split buffer struct into values and timestamp area similar to dln2-adc
> and make sure timestamp gets 8-byte aligned - ALIGN uses 4 as it aligns
> u16 elements not bytes - hopefully I got it right this time ;-)
> changes in v2:
> - use devm_iio_triggered_buffer_setup
> - calculate data array size from channel number (curtesy of at91-sama5d2_adc)
>
> drivers/iio/adc/Kconfig | 2 +
> drivers/iio/adc/rockchip_saradc.c | 146 ++++++++++++++++++++++--------
> 2 files changed, 112 insertions(+), 36 deletions(-)
>
> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
> index 12bb8b7ca1ff..8d2dd60614c6 100644
> --- a/drivers/iio/adc/Kconfig
> +++ b/drivers/iio/adc/Kconfig
> @@ -809,6 +809,8 @@ config ROCKCHIP_SARADC
> tristate "Rockchip SARADC driver"
> depends on ARCH_ROCKCHIP || (ARM && COMPILE_TEST)
> depends on RESET_CONTROLLER
> + select IIO_BUFFER
> + select IIO_TRIGGERED_BUFFER
> help
> Say yes here to build support for the SARADC found in SoCs from
> Rockchip.
> diff --git a/drivers/iio/adc/rockchip_saradc.c b/drivers/iio/adc/rockchip_saradc.c
> index 582ba047c4a6..0713363a4b43 100644
> --- a/drivers/iio/adc/rockchip_saradc.c
> +++ b/drivers/iio/adc/rockchip_saradc.c
> @@ -15,7 +15,11 @@
> #include <linux/delay.h>
> #include <linux/reset.h>
> #include <linux/regulator/consumer.h>
> +#include <linux/iio/buffer.h>
> #include <linux/iio/iio.h>
> +#include <linux/iio/trigger.h>
> +#include <linux/iio/trigger_consumer.h>
> +#include <linux/iio/triggered_buffer.h>
>
> #define SARADC_DATA 0x00
>
> @@ -32,9 +36,12 @@
> #define SARADC_DLY_PU_SOC_MASK 0x3f
>
> #define SARADC_TIMEOUT msecs_to_jiffies(100)
> +#define SARADC_MAX_CHANNELS 6
> +
> +/* buffer elements are u16, timestamp needs to be 8-byte aligned */
> +#define SARADC_BUFFER_NUM_U16 ALIGN(SARADC_MAX_CHANNELS, 4)
I may be going crazy but I think that will get you the 'start' of the
timestamp, not the length including it.
We should be seeing 24 bytes here = 12 u16s. Sanity check the value.
Running through the stack of defines.
#define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
#define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
#define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
ALIGN(6, 4) == __ALIGN_KERNEL(6, 4)
== __ALIGN_KERNEL_MASK(6, 3)
== (((6 + 3) & ~3)
which is 9 with the bottom two bits masked or b1001 & b1100 = 8 not 12
So I think you are looking for
ALIGN(SARADC_MAX_CHANNELS + sizeof(u64) / sizeof(u16), 4)
which will be ((10 + 3) & ~3) b1101 & b1100 = 12
>
> struct rockchip_saradc_data {
> - int num_bits;
> const struct iio_chan_spec *channels;
> int num_channels;
> unsigned long clk_rate;
> @@ -49,8 +56,37 @@ struct rockchip_saradc {
> struct reset_control *reset;
> const struct rockchip_saradc_data *data;
> u16 last_val;
> + const struct iio_chan_spec *last_chan;
> };
>
> +static void rockchip_saradc_power_down(struct rockchip_saradc *info)
> +{
> + /* Clear irq & power down adc */
> + writel_relaxed(0, info->regs + SARADC_CTRL);
> +}
> +
> +static int rockchip_saradc_conversion(struct rockchip_saradc *info,
> + struct iio_chan_spec const *chan)
> +{
> + reinit_completion(&info->completion);
> +
> + /* 8 clock periods as delay between power up and start cmd */
> + writel_relaxed(8, info->regs + SARADC_DLY_PU_SOC);
> +
> + info->last_chan = chan;
> +
> + /* Select the channel to be used and trigger conversion */
> + writel(SARADC_CTRL_POWER_CTRL
> + | (chan->channel & SARADC_CTRL_CHN_MASK)
> + | SARADC_CTRL_IRQ_ENABLE,
> + info->regs + SARADC_CTRL);
> +
> + if (!wait_for_completion_timeout(&info->completion, SARADC_TIMEOUT))
> + return -ETIMEDOUT;
> +
> + return 0;
> +}
> +
> static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
> struct iio_chan_spec const *chan,
> int *val, int *val2, long mask)
> @@ -62,24 +98,12 @@ static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
> case IIO_CHAN_INFO_RAW:
> mutex_lock(&indio_dev->mlock);
>
> - reinit_completion(&info->completion);
> -
> - /* 8 clock periods as delay between power up and start cmd */
> - writel_relaxed(8, info->regs + SARADC_DLY_PU_SOC);
> -
> - /* Select the channel to be used and trigger conversion */
> - writel(SARADC_CTRL_POWER_CTRL
> - | (chan->channel & SARADC_CTRL_CHN_MASK)
> - | SARADC_CTRL_IRQ_ENABLE,
> - info->regs + SARADC_CTRL);
> -
> - if (!wait_for_completion_timeout(&info->completion,
> - SARADC_TIMEOUT)) {
> - writel_relaxed(0, info->regs + SARADC_CTRL);
> + ret = rockchip_saradc_conversion(info, chan);
> + if (ret) {
> + rockchip_saradc_power_down(info);
> mutex_unlock(&indio_dev->mlock);
> - return -ETIMEDOUT;
> + return ret;
> }
> -
> *val = info->last_val;
> mutex_unlock(&indio_dev->mlock);
> return IIO_VAL_INT;
> @@ -91,7 +115,7 @@ static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
> }
>
> *val = ret / 1000;
> - *val2 = info->data->num_bits;
> + *val2 = chan->scan_type.realbits;
> return IIO_VAL_FRACTIONAL_LOG2;
> default:
> return -EINVAL;
> @@ -104,10 +128,9 @@ static irqreturn_t rockchip_saradc_isr(int irq, void *dev_id)
>
> /* Read value */
> info->last_val = readl_relaxed(info->regs + SARADC_DATA);
> - info->last_val &= GENMASK(info->data->num_bits - 1, 0);
> + info->last_val &= GENMASK(info->last_chan->scan_type.realbits - 1, 0);
>
> - /* Clear irq & power down adc */
> - writel_relaxed(0, info->regs + SARADC_CTRL);
> + rockchip_saradc_power_down(info);
>
> complete(&info->completion);
>
> @@ -118,51 +141,55 @@ static const struct iio_info rockchip_saradc_iio_info = {
> .read_raw = rockchip_saradc_read_raw,
> };
>
> -#define ADC_CHANNEL(_index, _id) { \
> +#define ADC_CHANNEL(_index, _id, _res) { \
> .type = IIO_VOLTAGE, \
> .indexed = 1, \
> .channel = _index, \
> .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
> .datasheet_name = _id, \
> + .scan_index = _index, \
> + .scan_type = { \
> + .sign = 'u', \
> + .realbits = _res, \
> + .storagebits = 16, \
> + .endianness = IIO_LE, \
> + }, \
> }
>
> static const struct iio_chan_spec rockchip_saradc_iio_channels[] = {
> - ADC_CHANNEL(0, "adc0"),
> - ADC_CHANNEL(1, "adc1"),
> - ADC_CHANNEL(2, "adc2"),
> + ADC_CHANNEL(0, "adc0", 10),
> + ADC_CHANNEL(1, "adc1", 10),
> + ADC_CHANNEL(2, "adc2", 10),
> };
>
> static const struct rockchip_saradc_data saradc_data = {
> - .num_bits = 10,
> .channels = rockchip_saradc_iio_channels,
> .num_channels = ARRAY_SIZE(rockchip_saradc_iio_channels),
> .clk_rate = 1000000,
> };
>
> static const struct iio_chan_spec rockchip_rk3066_tsadc_iio_channels[] = {
> - ADC_CHANNEL(0, "adc0"),
> - ADC_CHANNEL(1, "adc1"),
> + ADC_CHANNEL(0, "adc0", 12),
> + ADC_CHANNEL(1, "adc1", 12),
> };
>
> static const struct rockchip_saradc_data rk3066_tsadc_data = {
> - .num_bits = 12,
> .channels = rockchip_rk3066_tsadc_iio_channels,
> .num_channels = ARRAY_SIZE(rockchip_rk3066_tsadc_iio_channels),
> .clk_rate = 50000,
> };
>
> static const struct iio_chan_spec rockchip_rk3399_saradc_iio_channels[] = {
> - ADC_CHANNEL(0, "adc0"),
> - ADC_CHANNEL(1, "adc1"),
> - ADC_CHANNEL(2, "adc2"),
> - ADC_CHANNEL(3, "adc3"),
> - ADC_CHANNEL(4, "adc4"),
> - ADC_CHANNEL(5, "adc5"),
> + ADC_CHANNEL(0, "adc0", 10),
> + ADC_CHANNEL(1, "adc1", 10),
> + ADC_CHANNEL(2, "adc2", 10),
> + ADC_CHANNEL(3, "adc3", 10),
> + ADC_CHANNEL(4, "adc4", 10),
> + ADC_CHANNEL(5, "adc5", 10),
> };
>
> static const struct rockchip_saradc_data rk3399_saradc_data = {
> - .num_bits = 10,
> .channels = rockchip_rk3399_saradc_iio_channels,
> .num_channels = ARRAY_SIZE(rockchip_rk3399_saradc_iio_channels),
> .clk_rate = 1000000,
> @@ -193,6 +220,42 @@ static void rockchip_saradc_reset_controller(struct reset_control *reset)
> reset_control_deassert(reset);
> }
>
> +static irqreturn_t rockchip_saradc_trigger_handler(int irq, void *p)
> +{
> + struct iio_poll_func *pf = p;
> + struct iio_dev *i_dev = pf->indio_dev;
> + struct rockchip_saradc *info = iio_priv(i_dev);
> + struct {
> + u16 values[SARADC_BUFFER_NUM_U16];
> + int64_t timestamp;
> + } data;
> + int ret;
> + int i, j = 0;
> +
> + mutex_lock(&i_dev->mlock);
> +
> + for_each_set_bit(i, i_dev->active_scan_mask, i_dev->masklength) {
> + const struct iio_chan_spec *chan = &i_dev->channels[i];
> +
> + ret = rockchip_saradc_conversion(info, chan);
> + if (ret) {
> + rockchip_saradc_power_down(info);
> + goto out;
> + }
> +
> + data.values[j] = info->last_val;
> + j++;
> + }
> +
> + iio_push_to_buffers_with_timestamp(i_dev, &data, iio_get_time_ns(i_dev));
> +out:
> + mutex_unlock(&i_dev->mlock);
> +
> + iio_trigger_notify_done(i_dev->trig);
> +
> + return IRQ_HANDLED;
> +}
> +
> static int rockchip_saradc_probe(struct platform_device *pdev)
> {
> struct rockchip_saradc *info = NULL;
> @@ -221,6 +284,11 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
>
> info->data = match->data;
>
> + if (info->data->num_channels > SARADC_MAX_CHANNELS) {
> + dev_err(&pdev->dev, "max channels exceeded");
> + return -EINVAL;
How can that happen? Bug in the addition of a new device type?
If it's just paranoia against future code, perhaps add a comment to
say that.
> + }
> +
> mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> info->regs = devm_ioremap_resource(&pdev->dev, mem);
> if (IS_ERR(info->regs))
> @@ -315,6 +383,12 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
> indio_dev->channels = info->data->channels;
> indio_dev->num_channels = info->data->num_channels;
>
> + ret = devm_iio_triggered_buffer_setup(&indio_dev->dev, indio_dev, NULL,
> + rockchip_saradc_trigger_handler,
> + NULL);
> + if (ret)
> + goto err_clk;
> +
Please avoid mixing an matching between device managed an unmanaged interfaces.
It means the driver is not 'obviously correct' and hence harder to review.
Two choices here. Either use devm_add_action_or_reset to automatically
disable each clock + regulator in the managed release path, drop all the error
handling and remove (note this should be a precursor patch), or use
iio_triggered_buffer_setup and manually call iio_triggered_buffer_cleanup
in the right place in the remove function.
> ret = iio_device_register(indio_dev);
> if (ret)
> goto err_clk;
On Mon, 13 Apr 2020 18:55:12 +0200
Heiko Stübner <[email protected]> wrote:
> Hi Jonathan,
>
Hi Heiko,
> > > +/* buffer elements are u16, timestamp needs to be 8-byte aligned */
> > > +#define SARADC_BUFFER_NUM_U16 ALIGN(SARADC_MAX_CHANNELS, 4)
> > I may be going crazy but I think that will get you the 'start' of the
> > timestamp, not the length including it.
> >
> > We should be seeing 24 bytes here = 12 u16s. Sanity check the value.
> >
> > Running through the stack of defines.
> > #define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
> > #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
> > #define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
> >
> > ALIGN(6, 4) == __ALIGN_KERNEL(6, 4)
> > == __ALIGN_KERNEL_MASK(6, 3)
> > == (((6 + 3) & ~3)
> > which is 9 with the bottom two bits masked or b1001 & b1100 = 8 not 12
> >
> > So I think you are looking for
> > ALIGN(SARADC_MAX_CHANNELS + sizeof(u64) / sizeof(u16), 4)
> > which will be ((10 + 3) & ~3) b1101 & b1100 = 12
>
> hmm, getting the start of the timestamp was actually what I intended ;-)
> The dln2-adc driver did that fancy struct definition for its data. which
> I stole, see the part from blow:
Crossed emails. I realised I was being an idiot but had already clicked send :)
>
> > > + struct {
> > > + u16 values[SARADC_BUFFER_NUM_U16];
> > > + int64_t timestamp;
> > > + } data;
>
> So SARADC_BUFFER_NUM really is meant to only contain the
> number of actual buffer data - I guess I should explain that out better
> in the comment. Because defining this separate makes this so much
> more readable when we're not trying to implicitly add the timestamp
> space.
>
> And a size_of(data) for that struct then returned nicely these 24 bytes
> in my tests.
>
>
> > >
> > > struct rockchip_saradc_data {
> > > - int num_bits;
> > > const struct iio_chan_spec *channels;
> > > int num_channels;
> > > unsigned long clk_rate;
> > > @@ -49,8 +56,37 @@ struct rockchip_saradc {
> > > struct reset_control *reset;
> > > const struct rockchip_saradc_data *data;
> > > u16 last_val;
> > > + const struct iio_chan_spec *last_chan;
> > > };
> > >
> > > +static void rockchip_saradc_power_down(struct rockchip_saradc *info)
> > > +{
> > > + /* Clear irq & power down adc */
> > > + writel_relaxed(0, info->regs + SARADC_CTRL);
> > > +}
> > > +
> > > +static int rockchip_saradc_conversion(struct rockchip_saradc *info,
> > > + struct iio_chan_spec const *chan)
> > > +{
> > > + reinit_completion(&info->completion);
> > > +
> > > + /* 8 clock periods as delay between power up and start cmd */
> > > + writel_relaxed(8, info->regs + SARADC_DLY_PU_SOC);
> > > +
> > > + info->last_chan = chan;
> > > +
> > > + /* Select the channel to be used and trigger conversion */
> > > + writel(SARADC_CTRL_POWER_CTRL
> > > + | (chan->channel & SARADC_CTRL_CHN_MASK)
> > > + | SARADC_CTRL_IRQ_ENABLE,
> > > + info->regs + SARADC_CTRL);
> > > +
> > > + if (!wait_for_completion_timeout(&info->completion, SARADC_TIMEOUT))
> > > + return -ETIMEDOUT;
> > > +
> > > + return 0;
> > > +}
> > > +
> > > static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
> > > struct iio_chan_spec const *chan,
> > > int *val, int *val2, long mask)
> > > @@ -62,24 +98,12 @@ static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
> > > case IIO_CHAN_INFO_RAW:
> > > mutex_lock(&indio_dev->mlock);
> > >
> > > - reinit_completion(&info->completion);
> > > -
> > > - /* 8 clock periods as delay between power up and start cmd */
> > > - writel_relaxed(8, info->regs + SARADC_DLY_PU_SOC);
> > > -
> > > - /* Select the channel to be used and trigger conversion */
> > > - writel(SARADC_CTRL_POWER_CTRL
> > > - | (chan->channel & SARADC_CTRL_CHN_MASK)
> > > - | SARADC_CTRL_IRQ_ENABLE,
> > > - info->regs + SARADC_CTRL);
> > > -
> > > - if (!wait_for_completion_timeout(&info->completion,
> > > - SARADC_TIMEOUT)) {
> > > - writel_relaxed(0, info->regs + SARADC_CTRL);
> > > + ret = rockchip_saradc_conversion(info, chan);
> > > + if (ret) {
> > > + rockchip_saradc_power_down(info);
> > > mutex_unlock(&indio_dev->mlock);
> > > - return -ETIMEDOUT;
> > > + return ret;
> > > }
> > > -
> > > *val = info->last_val;
> > > mutex_unlock(&indio_dev->mlock);
> > > return IIO_VAL_INT;
> > > @@ -91,7 +115,7 @@ static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
> > > }
> > >
> > > *val = ret / 1000;
> > > - *val2 = info->data->num_bits;
> > > + *val2 = chan->scan_type.realbits;
> > > return IIO_VAL_FRACTIONAL_LOG2;
> > > default:
> > > return -EINVAL;
> > > @@ -104,10 +128,9 @@ static irqreturn_t rockchip_saradc_isr(int irq, void *dev_id)
> > >
> > > /* Read value */
> > > info->last_val = readl_relaxed(info->regs + SARADC_DATA);
> > > - info->last_val &= GENMASK(info->data->num_bits - 1, 0);
> > > + info->last_val &= GENMASK(info->last_chan->scan_type.realbits - 1, 0);
> > >
> > > - /* Clear irq & power down adc */
> > > - writel_relaxed(0, info->regs + SARADC_CTRL);
> > > + rockchip_saradc_power_down(info);
> > >
> > > complete(&info->completion);
> > >
> > > @@ -118,51 +141,55 @@ static const struct iio_info rockchip_saradc_iio_info = {
> > > .read_raw = rockchip_saradc_read_raw,
> > > };
> > >
> > > -#define ADC_CHANNEL(_index, _id) { \
> > > +#define ADC_CHANNEL(_index, _id, _res) { \
> > > .type = IIO_VOLTAGE, \
> > > .indexed = 1, \
> > > .channel = _index, \
> > > .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> > > .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
> > > .datasheet_name = _id, \
> > > + .scan_index = _index, \
> > > + .scan_type = { \
> > > + .sign = 'u', \
> > > + .realbits = _res, \
> > > + .storagebits = 16, \
> > > + .endianness = IIO_LE, \
> > > + }, \
> > > }
> > >
> > > static const struct iio_chan_spec rockchip_saradc_iio_channels[] = {
> > > - ADC_CHANNEL(0, "adc0"),
> > > - ADC_CHANNEL(1, "adc1"),
> > > - ADC_CHANNEL(2, "adc2"),
> > > + ADC_CHANNEL(0, "adc0", 10),
> > > + ADC_CHANNEL(1, "adc1", 10),
> > > + ADC_CHANNEL(2, "adc2", 10),
> > > };
> > >
> > > static const struct rockchip_saradc_data saradc_data = {
> > > - .num_bits = 10,
> > > .channels = rockchip_saradc_iio_channels,
> > > .num_channels = ARRAY_SIZE(rockchip_saradc_iio_channels),
> > > .clk_rate = 1000000,
> > > };
> > >
> > > static const struct iio_chan_spec rockchip_rk3066_tsadc_iio_channels[] = {
> > > - ADC_CHANNEL(0, "adc0"),
> > > - ADC_CHANNEL(1, "adc1"),
> > > + ADC_CHANNEL(0, "adc0", 12),
> > > + ADC_CHANNEL(1, "adc1", 12),
> > > };
> > >
> > > static const struct rockchip_saradc_data rk3066_tsadc_data = {
> > > - .num_bits = 12,
> > > .channels = rockchip_rk3066_tsadc_iio_channels,
> > > .num_channels = ARRAY_SIZE(rockchip_rk3066_tsadc_iio_channels),
> > > .clk_rate = 50000,
> > > };
> > >
> > > static const struct iio_chan_spec rockchip_rk3399_saradc_iio_channels[] = {
> > > - ADC_CHANNEL(0, "adc0"),
> > > - ADC_CHANNEL(1, "adc1"),
> > > - ADC_CHANNEL(2, "adc2"),
> > > - ADC_CHANNEL(3, "adc3"),
> > > - ADC_CHANNEL(4, "adc4"),
> > > - ADC_CHANNEL(5, "adc5"),
> > > + ADC_CHANNEL(0, "adc0", 10),
> > > + ADC_CHANNEL(1, "adc1", 10),
> > > + ADC_CHANNEL(2, "adc2", 10),
> > > + ADC_CHANNEL(3, "adc3", 10),
> > > + ADC_CHANNEL(4, "adc4", 10),
> > > + ADC_CHANNEL(5, "adc5", 10),
> > > };
> > >
> > > static const struct rockchip_saradc_data rk3399_saradc_data = {
> > > - .num_bits = 10,
> > > .channels = rockchip_rk3399_saradc_iio_channels,
> > > .num_channels = ARRAY_SIZE(rockchip_rk3399_saradc_iio_channels),
> > > .clk_rate = 1000000,
> > > @@ -193,6 +220,42 @@ static void rockchip_saradc_reset_controller(struct reset_control *reset)
> > > reset_control_deassert(reset);
> > > }
> > >
> > > +static irqreturn_t rockchip_saradc_trigger_handler(int irq, void *p)
> > > +{
> > > + struct iio_poll_func *pf = p;
> > > + struct iio_dev *i_dev = pf->indio_dev;
> > > + struct rockchip_saradc *info = iio_priv(i_dev);
> > > + struct {
> > > + u16 values[SARADC_BUFFER_NUM_U16];
> > > + int64_t timestamp;
> > > + } data;
> > > + int ret;
> > > + int i, j = 0;
> > > +
> > > + mutex_lock(&i_dev->mlock);
> > > +
> > > + for_each_set_bit(i, i_dev->active_scan_mask, i_dev->masklength) {
> > > + const struct iio_chan_spec *chan = &i_dev->channels[i];
> > > +
> > > + ret = rockchip_saradc_conversion(info, chan);
> > > + if (ret) {
> > > + rockchip_saradc_power_down(info);
> > > + goto out;
> > > + }
> > > +
> > > + data.values[j] = info->last_val;
> > > + j++;
> > > + }
> > > +
> > > + iio_push_to_buffers_with_timestamp(i_dev, &data, iio_get_time_ns(i_dev));
> > > +out:
> > > + mutex_unlock(&i_dev->mlock);
> > > +
> > > + iio_trigger_notify_done(i_dev->trig);
> > > +
> > > + return IRQ_HANDLED;
> > > +}
> > > +
> > > static int rockchip_saradc_probe(struct platform_device *pdev)
> > > {
> > > struct rockchip_saradc *info = NULL;
> > > @@ -221,6 +284,11 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
> > >
> > > info->data = match->data;
> > >
> > > + if (info->data->num_channels > SARADC_MAX_CHANNELS) {
> > > + dev_err(&pdev->dev, "max channels exceeded");
> > > + return -EINVAL;
> >
> > How can that happen? Bug in the addition of a new device type?
> > If it's just paranoia against future code, perhaps add a comment to
> > say that.
>
> yep that is "paranoia" for the case someone adds a fancy new 20 channel
> saradc variant and forgets to adapt the constant.
>
> I'll add a comment.
>
> >
> > > + }
> > > +
> > > mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > info->regs = devm_ioremap_resource(&pdev->dev, mem);
> > > if (IS_ERR(info->regs))
> > > @@ -315,6 +383,12 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
> > > indio_dev->channels = info->data->channels;
> > > indio_dev->num_channels = info->data->num_channels;
> > >
> > > + ret = devm_iio_triggered_buffer_setup(&indio_dev->dev, indio_dev, NULL,
> > > + rockchip_saradc_trigger_handler,
> > > + NULL);
> > > + if (ret)
> > > + goto err_clk;
> > > +
> >
> > Please avoid mixing an matching between device managed an unmanaged interfaces.
> > It means the driver is not 'obviously correct' and hence harder to review.
> >
> > Two choices here. Either use devm_add_action_or_reset to automatically
> > disable each clock + regulator in the managed release path, drop all the error
> > handling and remove (note this should be a precursor patch), or use
> > iio_triggered_buffer_setup and manually call iio_triggered_buffer_cleanup
> > in the right place in the remove function.
>
> I'll go with the devm_* approach, less complexity is better than adding more ;-)
>
>
> Heiko
>
> > > ret = iio_device_register(indio_dev);
> > > if (ret)
> > > goto err_clk;
> >
> >
>
>
>
>
On Mon, 13 Apr 2020 17:44:34 +0100
Jonathan Cameron <[email protected]> wrote:
> On Mon, 13 Apr 2020 00:42:51 +0200
> Heiko Stuebner <[email protected]> wrote:
>
> > From: Simon Xue <[email protected]>
> >
> > Add the ability to also support access via (triggered) buffers
> > next to the existing direct mode.
> >
> > Device in question is the Odroid Go Advance that connects a joystick
> > to two of the saradc channels for X and Y axis and the new (and still
> > pending) adc joystick driver of course wants to use triggered buffers
> > from the iio subsystem.
> >
> > Signed-off-by: Simon Xue <[email protected]>
> > [some simplifications and added commit description]
> > Signed-off-by: Heiko Stuebner <[email protected]>
>
> Comments inline.
>
> The issue with mixing managed and unmanaged allocations needs tidying up.
> Sorry if I missed that one before; I probably didn't open up the current
> driver to sanity check it :(
>
> Jonathan
>
> > ---
> > changes in v3:
> > - split buffer struct into values and timestamp area similar to dln2-adc
> > and make sure timestamp gets 8-byte aligned - ALIGN uses 4 as it aligns
> > u16 elements not bytes - hopefully I got it right this time ;-)
> > changes in v2:
> > - use devm_iio_triggered_buffer_setup
> > - calculate data array size from channel number (curtesy of at91-sama5d2_adc)
> >
> > drivers/iio/adc/Kconfig | 2 +
> > drivers/iio/adc/rockchip_saradc.c | 146 ++++++++++++++++++++++--------
> > 2 files changed, 112 insertions(+), 36 deletions(-)
> >
> > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
> > index 12bb8b7ca1ff..8d2dd60614c6 100644
> > --- a/drivers/iio/adc/Kconfig
> > +++ b/drivers/iio/adc/Kconfig
> > @@ -809,6 +809,8 @@ config ROCKCHIP_SARADC
> > tristate "Rockchip SARADC driver"
> > depends on ARCH_ROCKCHIP || (ARM && COMPILE_TEST)
> > depends on RESET_CONTROLLER
> > + select IIO_BUFFER
> > + select IIO_TRIGGERED_BUFFER
> > help
> > Say yes here to build support for the SARADC found in SoCs from
> > Rockchip.
> > diff --git a/drivers/iio/adc/rockchip_saradc.c b/drivers/iio/adc/rockchip_saradc.c
> > index 582ba047c4a6..0713363a4b43 100644
> > --- a/drivers/iio/adc/rockchip_saradc.c
> > +++ b/drivers/iio/adc/rockchip_saradc.c
> > @@ -15,7 +15,11 @@
> > #include <linux/delay.h>
> > #include <linux/reset.h>
> > #include <linux/regulator/consumer.h>
> > +#include <linux/iio/buffer.h>
> > #include <linux/iio/iio.h>
> > +#include <linux/iio/trigger.h>
> > +#include <linux/iio/trigger_consumer.h>
> > +#include <linux/iio/triggered_buffer.h>
> >
> > #define SARADC_DATA 0x00
> >
> > @@ -32,9 +36,12 @@
> > #define SARADC_DLY_PU_SOC_MASK 0x3f
> >
> > #define SARADC_TIMEOUT msecs_to_jiffies(100)
> > +#define SARADC_MAX_CHANNELS 6
> > +
> > +/* buffer elements are u16, timestamp needs to be 8-byte aligned */
> > +#define SARADC_BUFFER_NUM_U16 ALIGN(SARADC_MAX_CHANNELS, 4)
> I may be going crazy but I think that will get you the 'start' of the
> timestamp, not the length including it.
>
> We should be seeing 24 bytes here = 12 u16s. Sanity check the value.
>
> Running through the stack of defines.
> #define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
> #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
> #define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
>
> ALIGN(6, 4) == __ALIGN_KERNEL(6, 4)
> == __ALIGN_KERNEL_MASK(6, 3)
> == (((6 + 3) & ~3)
> which is 9 with the bottom two bits masked or b1001 & b1100 = 8 not 12
>
> So I think you are looking for
> ALIGN(SARADC_MAX_CHANNELS + sizeof(u64) / sizeof(u16), 4)
> which will be ((10 + 3) & ~3) b1101 & b1100 = 12
Doh. I see you then added the 64 bit as a separate element in
a structure. Note with that you will get the padding for
free anyway as this should be standard C alignment.
That's actually quite a nice way of ensuring we get the right
length!
Thanks,
Jonathan
>
> >
> > struct rockchip_saradc_data {
> > - int num_bits;
> > const struct iio_chan_spec *channels;
> > int num_channels;
> > unsigned long clk_rate;
> > @@ -49,8 +56,37 @@ struct rockchip_saradc {
> > struct reset_control *reset;
> > const struct rockchip_saradc_data *data;
> > u16 last_val;
> > + const struct iio_chan_spec *last_chan;
> > };
> >
> > +static void rockchip_saradc_power_down(struct rockchip_saradc *info)
> > +{
> > + /* Clear irq & power down adc */
> > + writel_relaxed(0, info->regs + SARADC_CTRL);
> > +}
> > +
> > +static int rockchip_saradc_conversion(struct rockchip_saradc *info,
> > + struct iio_chan_spec const *chan)
> > +{
> > + reinit_completion(&info->completion);
> > +
> > + /* 8 clock periods as delay between power up and start cmd */
> > + writel_relaxed(8, info->regs + SARADC_DLY_PU_SOC);
> > +
> > + info->last_chan = chan;
> > +
> > + /* Select the channel to be used and trigger conversion */
> > + writel(SARADC_CTRL_POWER_CTRL
> > + | (chan->channel & SARADC_CTRL_CHN_MASK)
> > + | SARADC_CTRL_IRQ_ENABLE,
> > + info->regs + SARADC_CTRL);
> > +
> > + if (!wait_for_completion_timeout(&info->completion, SARADC_TIMEOUT))
> > + return -ETIMEDOUT;
> > +
> > + return 0;
> > +}
> > +
> > static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
> > struct iio_chan_spec const *chan,
> > int *val, int *val2, long mask)
> > @@ -62,24 +98,12 @@ static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
> > case IIO_CHAN_INFO_RAW:
> > mutex_lock(&indio_dev->mlock);
> >
> > - reinit_completion(&info->completion);
> > -
> > - /* 8 clock periods as delay between power up and start cmd */
> > - writel_relaxed(8, info->regs + SARADC_DLY_PU_SOC);
> > -
> > - /* Select the channel to be used and trigger conversion */
> > - writel(SARADC_CTRL_POWER_CTRL
> > - | (chan->channel & SARADC_CTRL_CHN_MASK)
> > - | SARADC_CTRL_IRQ_ENABLE,
> > - info->regs + SARADC_CTRL);
> > -
> > - if (!wait_for_completion_timeout(&info->completion,
> > - SARADC_TIMEOUT)) {
> > - writel_relaxed(0, info->regs + SARADC_CTRL);
> > + ret = rockchip_saradc_conversion(info, chan);
> > + if (ret) {
> > + rockchip_saradc_power_down(info);
> > mutex_unlock(&indio_dev->mlock);
> > - return -ETIMEDOUT;
> > + return ret;
> > }
> > -
> > *val = info->last_val;
> > mutex_unlock(&indio_dev->mlock);
> > return IIO_VAL_INT;
> > @@ -91,7 +115,7 @@ static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
> > }
> >
> > *val = ret / 1000;
> > - *val2 = info->data->num_bits;
> > + *val2 = chan->scan_type.realbits;
> > return IIO_VAL_FRACTIONAL_LOG2;
> > default:
> > return -EINVAL;
> > @@ -104,10 +128,9 @@ static irqreturn_t rockchip_saradc_isr(int irq, void *dev_id)
> >
> > /* Read value */
> > info->last_val = readl_relaxed(info->regs + SARADC_DATA);
> > - info->last_val &= GENMASK(info->data->num_bits - 1, 0);
> > + info->last_val &= GENMASK(info->last_chan->scan_type.realbits - 1, 0);
> >
> > - /* Clear irq & power down adc */
> > - writel_relaxed(0, info->regs + SARADC_CTRL);
> > + rockchip_saradc_power_down(info);
> >
> > complete(&info->completion);
> >
> > @@ -118,51 +141,55 @@ static const struct iio_info rockchip_saradc_iio_info = {
> > .read_raw = rockchip_saradc_read_raw,
> > };
> >
> > -#define ADC_CHANNEL(_index, _id) { \
> > +#define ADC_CHANNEL(_index, _id, _res) { \
> > .type = IIO_VOLTAGE, \
> > .indexed = 1, \
> > .channel = _index, \
> > .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> > .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
> > .datasheet_name = _id, \
> > + .scan_index = _index, \
> > + .scan_type = { \
> > + .sign = 'u', \
> > + .realbits = _res, \
> > + .storagebits = 16, \
> > + .endianness = IIO_LE, \
> > + }, \
> > }
> >
> > static const struct iio_chan_spec rockchip_saradc_iio_channels[] = {
> > - ADC_CHANNEL(0, "adc0"),
> > - ADC_CHANNEL(1, "adc1"),
> > - ADC_CHANNEL(2, "adc2"),
> > + ADC_CHANNEL(0, "adc0", 10),
> > + ADC_CHANNEL(1, "adc1", 10),
> > + ADC_CHANNEL(2, "adc2", 10),
> > };
> >
> > static const struct rockchip_saradc_data saradc_data = {
> > - .num_bits = 10,
> > .channels = rockchip_saradc_iio_channels,
> > .num_channels = ARRAY_SIZE(rockchip_saradc_iio_channels),
> > .clk_rate = 1000000,
> > };
> >
> > static const struct iio_chan_spec rockchip_rk3066_tsadc_iio_channels[] = {
> > - ADC_CHANNEL(0, "adc0"),
> > - ADC_CHANNEL(1, "adc1"),
> > + ADC_CHANNEL(0, "adc0", 12),
> > + ADC_CHANNEL(1, "adc1", 12),
> > };
> >
> > static const struct rockchip_saradc_data rk3066_tsadc_data = {
> > - .num_bits = 12,
> > .channels = rockchip_rk3066_tsadc_iio_channels,
> > .num_channels = ARRAY_SIZE(rockchip_rk3066_tsadc_iio_channels),
> > .clk_rate = 50000,
> > };
> >
> > static const struct iio_chan_spec rockchip_rk3399_saradc_iio_channels[] = {
> > - ADC_CHANNEL(0, "adc0"),
> > - ADC_CHANNEL(1, "adc1"),
> > - ADC_CHANNEL(2, "adc2"),
> > - ADC_CHANNEL(3, "adc3"),
> > - ADC_CHANNEL(4, "adc4"),
> > - ADC_CHANNEL(5, "adc5"),
> > + ADC_CHANNEL(0, "adc0", 10),
> > + ADC_CHANNEL(1, "adc1", 10),
> > + ADC_CHANNEL(2, "adc2", 10),
> > + ADC_CHANNEL(3, "adc3", 10),
> > + ADC_CHANNEL(4, "adc4", 10),
> > + ADC_CHANNEL(5, "adc5", 10),
> > };
> >
> > static const struct rockchip_saradc_data rk3399_saradc_data = {
> > - .num_bits = 10,
> > .channels = rockchip_rk3399_saradc_iio_channels,
> > .num_channels = ARRAY_SIZE(rockchip_rk3399_saradc_iio_channels),
> > .clk_rate = 1000000,
> > @@ -193,6 +220,42 @@ static void rockchip_saradc_reset_controller(struct reset_control *reset)
> > reset_control_deassert(reset);
> > }
> >
> > +static irqreturn_t rockchip_saradc_trigger_handler(int irq, void *p)
> > +{
> > + struct iio_poll_func *pf = p;
> > + struct iio_dev *i_dev = pf->indio_dev;
> > + struct rockchip_saradc *info = iio_priv(i_dev);
> > + struct {
> > + u16 values[SARADC_BUFFER_NUM_U16];
> > + int64_t timestamp;
> > + } data;
> > + int ret;
> > + int i, j = 0;
> > +
> > + mutex_lock(&i_dev->mlock);
> > +
> > + for_each_set_bit(i, i_dev->active_scan_mask, i_dev->masklength) {
> > + const struct iio_chan_spec *chan = &i_dev->channels[i];
> > +
> > + ret = rockchip_saradc_conversion(info, chan);
> > + if (ret) {
> > + rockchip_saradc_power_down(info);
> > + goto out;
> > + }
> > +
> > + data.values[j] = info->last_val;
> > + j++;
> > + }
> > +
> > + iio_push_to_buffers_with_timestamp(i_dev, &data, iio_get_time_ns(i_dev));
> > +out:
> > + mutex_unlock(&i_dev->mlock);
> > +
> > + iio_trigger_notify_done(i_dev->trig);
> > +
> > + return IRQ_HANDLED;
> > +}
> > +
> > static int rockchip_saradc_probe(struct platform_device *pdev)
> > {
> > struct rockchip_saradc *info = NULL;
> > @@ -221,6 +284,11 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
> >
> > info->data = match->data;
> >
> > + if (info->data->num_channels > SARADC_MAX_CHANNELS) {
> > + dev_err(&pdev->dev, "max channels exceeded");
> > + return -EINVAL;
>
> How can that happen? Bug in the addition of a new device type?
> If it's just paranoia against future code, perhaps add a comment to
> say that.
>
> > + }
> > +
> > mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > info->regs = devm_ioremap_resource(&pdev->dev, mem);
> > if (IS_ERR(info->regs))
> > @@ -315,6 +383,12 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
> > indio_dev->channels = info->data->channels;
> > indio_dev->num_channels = info->data->num_channels;
> >
> > + ret = devm_iio_triggered_buffer_setup(&indio_dev->dev, indio_dev, NULL,
> > + rockchip_saradc_trigger_handler,
> > + NULL);
> > + if (ret)
> > + goto err_clk;
> > +
>
> Please avoid mixing an matching between device managed an unmanaged interfaces.
> It means the driver is not 'obviously correct' and hence harder to review.
>
> Two choices here. Either use devm_add_action_or_reset to automatically
> disable each clock + regulator in the managed release path, drop all the error
> handling and remove (note this should be a precursor patch), or use
> iio_triggered_buffer_setup and manually call iio_triggered_buffer_cleanup
> in the right place in the remove function.
>
> > ret = iio_device_register(indio_dev);
> > if (ret)
> > goto err_clk;
>
Hi Jonathan,
Am Montag, 13. April 2020, 18:44:34 CEST schrieb Jonathan Cameron:
> On Mon, 13 Apr 2020 00:42:51 +0200
> Heiko Stuebner <[email protected]> wrote:
>
> > From: Simon Xue <[email protected]>
> >
> > Add the ability to also support access via (triggered) buffers
> > next to the existing direct mode.
> >
> > Device in question is the Odroid Go Advance that connects a joystick
> > to two of the saradc channels for X and Y axis and the new (and still
> > pending) adc joystick driver of course wants to use triggered buffers
> > from the iio subsystem.
> >
> > Signed-off-by: Simon Xue <[email protected]>
> > [some simplifications and added commit description]
> > Signed-off-by: Heiko Stuebner <[email protected]>
>
> Comments inline.
>
> The issue with mixing managed and unmanaged allocations needs tidying up.
> Sorry if I missed that one before; I probably didn't open up the current
> driver to sanity check it :(
>
> Jonathan
>
> > ---
> > changes in v3:
> > - split buffer struct into values and timestamp area similar to dln2-adc
> > and make sure timestamp gets 8-byte aligned - ALIGN uses 4 as it aligns
> > u16 elements not bytes - hopefully I got it right this time ;-)
> > changes in v2:
> > - use devm_iio_triggered_buffer_setup
> > - calculate data array size from channel number (curtesy of at91-sama5d2_adc)
> >
> > drivers/iio/adc/Kconfig | 2 +
> > drivers/iio/adc/rockchip_saradc.c | 146 ++++++++++++++++++++++--------
> > 2 files changed, 112 insertions(+), 36 deletions(-)
> >
> > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
> > index 12bb8b7ca1ff..8d2dd60614c6 100644
> > --- a/drivers/iio/adc/Kconfig
> > +++ b/drivers/iio/adc/Kconfig
> > @@ -809,6 +809,8 @@ config ROCKCHIP_SARADC
> > tristate "Rockchip SARADC driver"
> > depends on ARCH_ROCKCHIP || (ARM && COMPILE_TEST)
> > depends on RESET_CONTROLLER
> > + select IIO_BUFFER
> > + select IIO_TRIGGERED_BUFFER
> > help
> > Say yes here to build support for the SARADC found in SoCs from
> > Rockchip.
> > diff --git a/drivers/iio/adc/rockchip_saradc.c b/drivers/iio/adc/rockchip_saradc.c
> > index 582ba047c4a6..0713363a4b43 100644
> > --- a/drivers/iio/adc/rockchip_saradc.c
> > +++ b/drivers/iio/adc/rockchip_saradc.c
> > @@ -15,7 +15,11 @@
> > #include <linux/delay.h>
> > #include <linux/reset.h>
> > #include <linux/regulator/consumer.h>
> > +#include <linux/iio/buffer.h>
> > #include <linux/iio/iio.h>
> > +#include <linux/iio/trigger.h>
> > +#include <linux/iio/trigger_consumer.h>
> > +#include <linux/iio/triggered_buffer.h>
> >
> > #define SARADC_DATA 0x00
> >
> > @@ -32,9 +36,12 @@
> > #define SARADC_DLY_PU_SOC_MASK 0x3f
> >
> > #define SARADC_TIMEOUT msecs_to_jiffies(100)
> > +#define SARADC_MAX_CHANNELS 6
> > +
> > +/* buffer elements are u16, timestamp needs to be 8-byte aligned */
> > +#define SARADC_BUFFER_NUM_U16 ALIGN(SARADC_MAX_CHANNELS, 4)
> I may be going crazy but I think that will get you the 'start' of the
> timestamp, not the length including it.
>
> We should be seeing 24 bytes here = 12 u16s. Sanity check the value.
>
> Running through the stack of defines.
> #define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
> #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
> #define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
>
> ALIGN(6, 4) == __ALIGN_KERNEL(6, 4)
> == __ALIGN_KERNEL_MASK(6, 3)
> == (((6 + 3) & ~3)
> which is 9 with the bottom two bits masked or b1001 & b1100 = 8 not 12
>
> So I think you are looking for
> ALIGN(SARADC_MAX_CHANNELS + sizeof(u64) / sizeof(u16), 4)
> which will be ((10 + 3) & ~3) b1101 & b1100 = 12
hmm, getting the start of the timestamp was actually what I intended ;-)
The dln2-adc driver did that fancy struct definition for its data. which
I stole, see the part from blow:
> > + struct {
> > + u16 values[SARADC_BUFFER_NUM_U16];
> > + int64_t timestamp;
> > + } data;
So SARADC_BUFFER_NUM really is meant to only contain the
number of actual buffer data - I guess I should explain that out better
in the comment. Because defining this separate makes this so much
more readable when we're not trying to implicitly add the timestamp
space.
And a size_of(data) for that struct then returned nicely these 24 bytes
in my tests.
> >
> > struct rockchip_saradc_data {
> > - int num_bits;
> > const struct iio_chan_spec *channels;
> > int num_channels;
> > unsigned long clk_rate;
> > @@ -49,8 +56,37 @@ struct rockchip_saradc {
> > struct reset_control *reset;
> > const struct rockchip_saradc_data *data;
> > u16 last_val;
> > + const struct iio_chan_spec *last_chan;
> > };
> >
> > +static void rockchip_saradc_power_down(struct rockchip_saradc *info)
> > +{
> > + /* Clear irq & power down adc */
> > + writel_relaxed(0, info->regs + SARADC_CTRL);
> > +}
> > +
> > +static int rockchip_saradc_conversion(struct rockchip_saradc *info,
> > + struct iio_chan_spec const *chan)
> > +{
> > + reinit_completion(&info->completion);
> > +
> > + /* 8 clock periods as delay between power up and start cmd */
> > + writel_relaxed(8, info->regs + SARADC_DLY_PU_SOC);
> > +
> > + info->last_chan = chan;
> > +
> > + /* Select the channel to be used and trigger conversion */
> > + writel(SARADC_CTRL_POWER_CTRL
> > + | (chan->channel & SARADC_CTRL_CHN_MASK)
> > + | SARADC_CTRL_IRQ_ENABLE,
> > + info->regs + SARADC_CTRL);
> > +
> > + if (!wait_for_completion_timeout(&info->completion, SARADC_TIMEOUT))
> > + return -ETIMEDOUT;
> > +
> > + return 0;
> > +}
> > +
> > static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
> > struct iio_chan_spec const *chan,
> > int *val, int *val2, long mask)
> > @@ -62,24 +98,12 @@ static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
> > case IIO_CHAN_INFO_RAW:
> > mutex_lock(&indio_dev->mlock);
> >
> > - reinit_completion(&info->completion);
> > -
> > - /* 8 clock periods as delay between power up and start cmd */
> > - writel_relaxed(8, info->regs + SARADC_DLY_PU_SOC);
> > -
> > - /* Select the channel to be used and trigger conversion */
> > - writel(SARADC_CTRL_POWER_CTRL
> > - | (chan->channel & SARADC_CTRL_CHN_MASK)
> > - | SARADC_CTRL_IRQ_ENABLE,
> > - info->regs + SARADC_CTRL);
> > -
> > - if (!wait_for_completion_timeout(&info->completion,
> > - SARADC_TIMEOUT)) {
> > - writel_relaxed(0, info->regs + SARADC_CTRL);
> > + ret = rockchip_saradc_conversion(info, chan);
> > + if (ret) {
> > + rockchip_saradc_power_down(info);
> > mutex_unlock(&indio_dev->mlock);
> > - return -ETIMEDOUT;
> > + return ret;
> > }
> > -
> > *val = info->last_val;
> > mutex_unlock(&indio_dev->mlock);
> > return IIO_VAL_INT;
> > @@ -91,7 +115,7 @@ static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
> > }
> >
> > *val = ret / 1000;
> > - *val2 = info->data->num_bits;
> > + *val2 = chan->scan_type.realbits;
> > return IIO_VAL_FRACTIONAL_LOG2;
> > default:
> > return -EINVAL;
> > @@ -104,10 +128,9 @@ static irqreturn_t rockchip_saradc_isr(int irq, void *dev_id)
> >
> > /* Read value */
> > info->last_val = readl_relaxed(info->regs + SARADC_DATA);
> > - info->last_val &= GENMASK(info->data->num_bits - 1, 0);
> > + info->last_val &= GENMASK(info->last_chan->scan_type.realbits - 1, 0);
> >
> > - /* Clear irq & power down adc */
> > - writel_relaxed(0, info->regs + SARADC_CTRL);
> > + rockchip_saradc_power_down(info);
> >
> > complete(&info->completion);
> >
> > @@ -118,51 +141,55 @@ static const struct iio_info rockchip_saradc_iio_info = {
> > .read_raw = rockchip_saradc_read_raw,
> > };
> >
> > -#define ADC_CHANNEL(_index, _id) { \
> > +#define ADC_CHANNEL(_index, _id, _res) { \
> > .type = IIO_VOLTAGE, \
> > .indexed = 1, \
> > .channel = _index, \
> > .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> > .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
> > .datasheet_name = _id, \
> > + .scan_index = _index, \
> > + .scan_type = { \
> > + .sign = 'u', \
> > + .realbits = _res, \
> > + .storagebits = 16, \
> > + .endianness = IIO_LE, \
> > + }, \
> > }
> >
> > static const struct iio_chan_spec rockchip_saradc_iio_channels[] = {
> > - ADC_CHANNEL(0, "adc0"),
> > - ADC_CHANNEL(1, "adc1"),
> > - ADC_CHANNEL(2, "adc2"),
> > + ADC_CHANNEL(0, "adc0", 10),
> > + ADC_CHANNEL(1, "adc1", 10),
> > + ADC_CHANNEL(2, "adc2", 10),
> > };
> >
> > static const struct rockchip_saradc_data saradc_data = {
> > - .num_bits = 10,
> > .channels = rockchip_saradc_iio_channels,
> > .num_channels = ARRAY_SIZE(rockchip_saradc_iio_channels),
> > .clk_rate = 1000000,
> > };
> >
> > static const struct iio_chan_spec rockchip_rk3066_tsadc_iio_channels[] = {
> > - ADC_CHANNEL(0, "adc0"),
> > - ADC_CHANNEL(1, "adc1"),
> > + ADC_CHANNEL(0, "adc0", 12),
> > + ADC_CHANNEL(1, "adc1", 12),
> > };
> >
> > static const struct rockchip_saradc_data rk3066_tsadc_data = {
> > - .num_bits = 12,
> > .channels = rockchip_rk3066_tsadc_iio_channels,
> > .num_channels = ARRAY_SIZE(rockchip_rk3066_tsadc_iio_channels),
> > .clk_rate = 50000,
> > };
> >
> > static const struct iio_chan_spec rockchip_rk3399_saradc_iio_channels[] = {
> > - ADC_CHANNEL(0, "adc0"),
> > - ADC_CHANNEL(1, "adc1"),
> > - ADC_CHANNEL(2, "adc2"),
> > - ADC_CHANNEL(3, "adc3"),
> > - ADC_CHANNEL(4, "adc4"),
> > - ADC_CHANNEL(5, "adc5"),
> > + ADC_CHANNEL(0, "adc0", 10),
> > + ADC_CHANNEL(1, "adc1", 10),
> > + ADC_CHANNEL(2, "adc2", 10),
> > + ADC_CHANNEL(3, "adc3", 10),
> > + ADC_CHANNEL(4, "adc4", 10),
> > + ADC_CHANNEL(5, "adc5", 10),
> > };
> >
> > static const struct rockchip_saradc_data rk3399_saradc_data = {
> > - .num_bits = 10,
> > .channels = rockchip_rk3399_saradc_iio_channels,
> > .num_channels = ARRAY_SIZE(rockchip_rk3399_saradc_iio_channels),
> > .clk_rate = 1000000,
> > @@ -193,6 +220,42 @@ static void rockchip_saradc_reset_controller(struct reset_control *reset)
> > reset_control_deassert(reset);
> > }
> >
> > +static irqreturn_t rockchip_saradc_trigger_handler(int irq, void *p)
> > +{
> > + struct iio_poll_func *pf = p;
> > + struct iio_dev *i_dev = pf->indio_dev;
> > + struct rockchip_saradc *info = iio_priv(i_dev);
> > + struct {
> > + u16 values[SARADC_BUFFER_NUM_U16];
> > + int64_t timestamp;
> > + } data;
> > + int ret;
> > + int i, j = 0;
> > +
> > + mutex_lock(&i_dev->mlock);
> > +
> > + for_each_set_bit(i, i_dev->active_scan_mask, i_dev->masklength) {
> > + const struct iio_chan_spec *chan = &i_dev->channels[i];
> > +
> > + ret = rockchip_saradc_conversion(info, chan);
> > + if (ret) {
> > + rockchip_saradc_power_down(info);
> > + goto out;
> > + }
> > +
> > + data.values[j] = info->last_val;
> > + j++;
> > + }
> > +
> > + iio_push_to_buffers_with_timestamp(i_dev, &data, iio_get_time_ns(i_dev));
> > +out:
> > + mutex_unlock(&i_dev->mlock);
> > +
> > + iio_trigger_notify_done(i_dev->trig);
> > +
> > + return IRQ_HANDLED;
> > +}
> > +
> > static int rockchip_saradc_probe(struct platform_device *pdev)
> > {
> > struct rockchip_saradc *info = NULL;
> > @@ -221,6 +284,11 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
> >
> > info->data = match->data;
> >
> > + if (info->data->num_channels > SARADC_MAX_CHANNELS) {
> > + dev_err(&pdev->dev, "max channels exceeded");
> > + return -EINVAL;
>
> How can that happen? Bug in the addition of a new device type?
> If it's just paranoia against future code, perhaps add a comment to
> say that.
yep that is "paranoia" for the case someone adds a fancy new 20 channel
saradc variant and forgets to adapt the constant.
I'll add a comment.
>
> > + }
> > +
> > mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > info->regs = devm_ioremap_resource(&pdev->dev, mem);
> > if (IS_ERR(info->regs))
> > @@ -315,6 +383,12 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
> > indio_dev->channels = info->data->channels;
> > indio_dev->num_channels = info->data->num_channels;
> >
> > + ret = devm_iio_triggered_buffer_setup(&indio_dev->dev, indio_dev, NULL,
> > + rockchip_saradc_trigger_handler,
> > + NULL);
> > + if (ret)
> > + goto err_clk;
> > +
>
> Please avoid mixing an matching between device managed an unmanaged interfaces.
> It means the driver is not 'obviously correct' and hence harder to review.
>
> Two choices here. Either use devm_add_action_or_reset to automatically
> disable each clock + regulator in the managed release path, drop all the error
> handling and remove (note this should be a precursor patch), or use
> iio_triggered_buffer_setup and manually call iio_triggered_buffer_cleanup
> in the right place in the remove function.
I'll go with the devm_* approach, less complexity is better than adding more ;-)
Heiko
> > ret = iio_device_register(indio_dev);
> > if (ret)
> > goto err_clk;
>
>