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-rw-r--r--drivers/iio/adc/Kconfig3
-rw-r--r--drivers/iio/adc/aspeed_adc.c25
-rw-r--r--drivers/iio/adc/at91-sama5d2_adc.c456
-rw-r--r--drivers/iio/adc/at91_adc.c4
-rw-r--r--drivers/iio/adc/axp288_adc.c20
-rw-r--r--drivers/iio/adc/hx711.c134
-rw-r--r--drivers/iio/adc/ina2xx-adc.c317
-rw-r--r--drivers/iio/adc/meson_saradc.c60
-rw-r--r--drivers/iio/adc/qcom-vadc-common.c4
-rw-r--r--drivers/iio/adc/stm32-adc-core.c14
-rw-r--r--drivers/iio/adc/stm32-adc-core.h14
-rw-r--r--drivers/iio/adc/stm32-adc.c199
-rw-r--r--drivers/iio/adc/ti_am335x_adc.c2
13 files changed, 955 insertions, 297 deletions
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 39e3b345a6c8..72bc2b71765a 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -158,6 +158,7 @@ config AT91_SAMA5D2_ADC
tristate "Atmel AT91 SAMA5D2 ADC"
depends on ARCH_AT91 || COMPILE_TEST
depends on HAS_IOMEM
+ depends on HAS_DMA
select IIO_TRIGGERED_BUFFER
help
Say yes here to build support for Atmel SAMA5D2 ADC which is
@@ -318,6 +319,8 @@ config HI8435
config HX711
tristate "AVIA HX711 ADC for weight cells"
depends on GPIOLIB
+ select IIO_BUFFER
+ select IIO_TRIGGERED_BUFFER
help
If you say yes here you get support for AVIA HX711 ADC which is used
for weigh cells
diff --git a/drivers/iio/adc/aspeed_adc.c b/drivers/iio/adc/aspeed_adc.c
index 8a958d5f1905..327a49ba1991 100644
--- a/drivers/iio/adc/aspeed_adc.c
+++ b/drivers/iio/adc/aspeed_adc.c
@@ -17,6 +17,7 @@
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
+#include <linux/reset.h>
#include <linux/spinlock.h>
#include <linux/types.h>
@@ -53,11 +54,12 @@ struct aspeed_adc_model_data {
};
struct aspeed_adc_data {
- struct device *dev;
- void __iomem *base;
- spinlock_t clk_lock;
- struct clk_hw *clk_prescaler;
- struct clk_hw *clk_scaler;
+ struct device *dev;
+ void __iomem *base;
+ spinlock_t clk_lock;
+ struct clk_hw *clk_prescaler;
+ struct clk_hw *clk_scaler;
+ struct reset_control *rst;
};
#define ASPEED_CHAN(_idx, _data_reg_addr) { \
@@ -217,6 +219,15 @@ static int aspeed_adc_probe(struct platform_device *pdev)
goto scaler_error;
}
+ data->rst = devm_reset_control_get_exclusive(&pdev->dev, NULL);
+ if (IS_ERR(data->rst)) {
+ dev_err(&pdev->dev,
+ "invalid or missing reset controller device tree entry");
+ ret = PTR_ERR(data->rst);
+ goto reset_error;
+ }
+ reset_control_deassert(data->rst);
+
model_data = of_device_get_match_data(&pdev->dev);
if (model_data->wait_init_sequence) {
@@ -263,9 +274,10 @@ iio_register_error:
writel(ASPEED_OPERATION_MODE_POWER_DOWN,
data->base + ASPEED_REG_ENGINE_CONTROL);
clk_disable_unprepare(data->clk_scaler->clk);
+reset_error:
+ reset_control_assert(data->rst);
clk_enable_error:
clk_hw_unregister_divider(data->clk_scaler);
-
scaler_error:
clk_hw_unregister_divider(data->clk_prescaler);
return ret;
@@ -280,6 +292,7 @@ static int aspeed_adc_remove(struct platform_device *pdev)
writel(ASPEED_OPERATION_MODE_POWER_DOWN,
data->base + ASPEED_REG_ENGINE_CONTROL);
clk_disable_unprepare(data->clk_scaler->clk);
+ reset_control_assert(data->rst);
clk_hw_unregister_divider(data->clk_scaler);
clk_hw_unregister_divider(data->clk_prescaler);
diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
index 755a493c2a2c..4eff8351ce29 100644
--- a/drivers/iio/adc/at91-sama5d2_adc.c
+++ b/drivers/iio/adc/at91-sama5d2_adc.c
@@ -16,6 +16,8 @@
#include <linux/bitops.h>
#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/module.h>
@@ -100,6 +102,8 @@
#define AT91_SAMA5D2_LCDR 0x20
/* Interrupt Enable Register */
#define AT91_SAMA5D2_IER 0x24
+/* Interrupt Enable Register - general overrun error */
+#define AT91_SAMA5D2_IER_GOVRE BIT(25)
/* Interrupt Disable Register */
#define AT91_SAMA5D2_IDR 0x28
/* Interrupt Mask Register */
@@ -167,13 +171,19 @@
/*
* Maximum number of bytes to hold conversion from all channels
- * plus the timestamp
+ * without the timestamp.
*/
-#define AT91_BUFFER_MAX_BYTES ((AT91_SAMA5D2_SINGLE_CHAN_CNT + \
- AT91_SAMA5D2_DIFF_CHAN_CNT) * 2 + 8)
+#define AT91_BUFFER_MAX_CONVERSION_BYTES ((AT91_SAMA5D2_SINGLE_CHAN_CNT + \
+ AT91_SAMA5D2_DIFF_CHAN_CNT) * 2)
+
+/* This total must also include the timestamp */
+#define AT91_BUFFER_MAX_BYTES (AT91_BUFFER_MAX_CONVERSION_BYTES + 8)
#define AT91_BUFFER_MAX_HWORDS (AT91_BUFFER_MAX_BYTES / 2)
+#define AT91_HWFIFO_MAX_SIZE_STR "128"
+#define AT91_HWFIFO_MAX_SIZE 128
+
#define AT91_SAMA5D2_CHAN_SINGLE(num, addr) \
{ \
.type = IIO_VOLTAGE, \
@@ -228,6 +238,28 @@ struct at91_adc_trigger {
bool hw_trig;
};
+/**
+ * at91_adc_dma - at91-sama5d2 dma information struct
+ * @dma_chan: the dma channel acquired
+ * @rx_buf: dma coherent allocated area
+ * @rx_dma_buf: dma handler for the buffer
+ * @phys_addr: physical address of the ADC base register
+ * @buf_idx: index inside the dma buffer where reading was last done
+ * @rx_buf_sz: size of buffer used by DMA operation
+ * @watermark: number of conversions to copy before DMA triggers irq
+ * @dma_ts: hold the start timestamp of dma operation
+ */
+struct at91_adc_dma {
+ struct dma_chan *dma_chan;
+ u8 *rx_buf;
+ dma_addr_t rx_dma_buf;
+ phys_addr_t phys_addr;
+ int buf_idx;
+ int rx_buf_sz;
+ int watermark;
+ s64 dma_ts;
+};
+
struct at91_adc_state {
void __iomem *base;
int irq;
@@ -242,6 +274,7 @@ struct at91_adc_state {
u32 conversion_value;
struct at91_adc_soc_info soc_info;
wait_queue_head_t wq_data_available;
+ struct at91_adc_dma dma_st;
u16 buffer[AT91_BUFFER_MAX_HWORDS];
/*
* lock to prevent concurrent 'single conversion' requests through
@@ -322,11 +355,17 @@ static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
if (state) {
at91_adc_writel(st, AT91_SAMA5D2_CHER,
BIT(chan->channel));
- at91_adc_writel(st, AT91_SAMA5D2_IER,
- BIT(chan->channel));
+ /* enable irq only if not using DMA */
+ if (!st->dma_st.dma_chan) {
+ at91_adc_writel(st, AT91_SAMA5D2_IER,
+ BIT(chan->channel));
+ }
} else {
- at91_adc_writel(st, AT91_SAMA5D2_IDR,
- BIT(chan->channel));
+ /* disable irq only if not using DMA */
+ if (!st->dma_st.dma_chan) {
+ at91_adc_writel(st, AT91_SAMA5D2_IDR,
+ BIT(chan->channel));
+ }
at91_adc_writel(st, AT91_SAMA5D2_CHDR,
BIT(chan->channel));
}
@@ -340,6 +379,10 @@ static int at91_adc_reenable_trigger(struct iio_trigger *trig)
struct iio_dev *indio = iio_trigger_get_drvdata(trig);
struct at91_adc_state *st = iio_priv(indio);
+ /* if we are using DMA, we must not reenable irq after each trigger */
+ if (st->dma_st.dma_chan)
+ return 0;
+
enable_irq(st->irq);
/* Needed to ACK the DRDY interruption */
@@ -350,6 +393,153 @@ static int at91_adc_reenable_trigger(struct iio_trigger *trig)
static const struct iio_trigger_ops at91_adc_trigger_ops = {
.set_trigger_state = &at91_adc_configure_trigger,
.try_reenable = &at91_adc_reenable_trigger,
+ .validate_device = iio_trigger_validate_own_device,
+};
+
+static int at91_adc_dma_size_done(struct at91_adc_state *st)
+{
+ struct dma_tx_state state;
+ enum dma_status status;
+ int i, size;
+
+ status = dmaengine_tx_status(st->dma_st.dma_chan,
+ st->dma_st.dma_chan->cookie,
+ &state);
+ if (status != DMA_IN_PROGRESS)
+ return 0;
+
+ /* Transferred length is size in bytes from end of buffer */
+ i = st->dma_st.rx_buf_sz - state.residue;
+
+ /* Return available bytes */
+ if (i >= st->dma_st.buf_idx)
+ size = i - st->dma_st.buf_idx;
+ else
+ size = st->dma_st.rx_buf_sz + i - st->dma_st.buf_idx;
+ return size;
+}
+
+static void at91_dma_buffer_done(void *data)
+{
+ struct iio_dev *indio_dev = data;
+
+ iio_trigger_poll_chained(indio_dev->trig);
+}
+
+static int at91_adc_dma_start(struct iio_dev *indio_dev)
+{
+ struct at91_adc_state *st = iio_priv(indio_dev);
+ struct dma_async_tx_descriptor *desc;
+ dma_cookie_t cookie;
+ int ret;
+ u8 bit;
+
+ if (!st->dma_st.dma_chan)
+ return 0;
+
+ /* we start a new DMA, so set buffer index to start */
+ st->dma_st.buf_idx = 0;
+
+ /*
+ * compute buffer size w.r.t. watermark and enabled channels.
+ * scan_bytes is aligned so we need an exact size for DMA
+ */
+ st->dma_st.rx_buf_sz = 0;
+
+ for_each_set_bit(bit, indio_dev->active_scan_mask,
+ indio_dev->num_channels) {
+ struct iio_chan_spec const *chan = indio_dev->channels + bit;
+
+ st->dma_st.rx_buf_sz += chan->scan_type.storagebits / 8;
+ }
+ st->dma_st.rx_buf_sz *= st->dma_st.watermark;
+
+ /* Prepare a DMA cyclic transaction */
+ desc = dmaengine_prep_dma_cyclic(st->dma_st.dma_chan,
+ st->dma_st.rx_dma_buf,
+ st->dma_st.rx_buf_sz,
+ st->dma_st.rx_buf_sz / 2,
+ DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT);
+
+ if (!desc) {
+ dev_err(&indio_dev->dev, "cannot prepare DMA cyclic\n");
+ return -EBUSY;
+ }
+
+ desc->callback = at91_dma_buffer_done;
+ desc->callback_param = indio_dev;
+
+ cookie = dmaengine_submit(desc);
+ ret = dma_submit_error(cookie);
+ if (ret) {
+ dev_err(&indio_dev->dev, "cannot submit DMA cyclic\n");
+ dmaengine_terminate_async(st->dma_st.dma_chan);
+ return ret;
+ }
+
+ /* enable general overrun error signaling */
+ at91_adc_writel(st, AT91_SAMA5D2_IER, AT91_SAMA5D2_IER_GOVRE);
+ /* Issue pending DMA requests */
+ dma_async_issue_pending(st->dma_st.dma_chan);
+
+ /* consider current time as DMA start time for timestamps */
+ st->dma_st.dma_ts = iio_get_time_ns(indio_dev);
+
+ dev_dbg(&indio_dev->dev, "DMA cyclic started\n");
+
+ return 0;
+}
+
+static int at91_adc_buffer_postenable(struct iio_dev *indio_dev)
+{
+ int ret;
+
+ ret = at91_adc_dma_start(indio_dev);
+ if (ret) {
+ dev_err(&indio_dev->dev, "buffer postenable failed\n");
+ return ret;
+ }
+
+ return iio_triggered_buffer_postenable(indio_dev);
+}
+
+static int at91_adc_buffer_predisable(struct iio_dev *indio_dev)
+{
+ struct at91_adc_state *st = iio_priv(indio_dev);
+ int ret;
+ u8 bit;
+
+ ret = iio_triggered_buffer_predisable(indio_dev);
+ if (ret < 0)
+ dev_err(&indio_dev->dev, "buffer predisable failed\n");
+
+ if (!st->dma_st.dma_chan)
+ return ret;
+
+ /* if we are using DMA we must clear registers and end DMA */
+ dmaengine_terminate_sync(st->dma_st.dma_chan);
+
+ /*
+ * For each enabled channel we must read the last converted value
+ * to clear EOC status and not get a possible interrupt later.
+ * This value is being read by DMA from LCDR anyway
+ */
+ for_each_set_bit(bit, indio_dev->active_scan_mask,
+ indio_dev->num_channels) {
+ struct iio_chan_spec const *chan = indio_dev->channels + bit;
+
+ if (st->dma_st.dma_chan)
+ at91_adc_readl(st, chan->address);
+ }
+
+ /* read overflow register to clear possible overflow status */
+ at91_adc_readl(st, AT91_SAMA5D2_OVER);
+ return ret;
+}
+
+static const struct iio_buffer_setup_ops at91_buffer_setup_ops = {
+ .postenable = &at91_adc_buffer_postenable,
+ .predisable = &at91_adc_buffer_predisable,
};
static struct iio_trigger *at91_adc_allocate_trigger(struct iio_dev *indio,
@@ -388,24 +578,77 @@ static int at91_adc_trigger_init(struct iio_dev *indio)
return 0;
}
-static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
+static void at91_adc_trigger_handler_nodma(struct iio_dev *indio_dev,
+ struct iio_poll_func *pf)
{
- struct iio_poll_func *pf = p;
- struct iio_dev *indio = pf->indio_dev;
- struct at91_adc_state *st = iio_priv(indio);
+ struct at91_adc_state *st = iio_priv(indio_dev);
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;
+ for_each_set_bit(bit, indio_dev->active_scan_mask,
+ indio_dev->num_channels) {
+ struct iio_chan_spec const *chan = indio_dev->channels + bit;
st->buffer[i] = at91_adc_readl(st, chan->address);
i++;
}
+ iio_push_to_buffers_with_timestamp(indio_dev, st->buffer,
+ pf->timestamp);
+}
- iio_push_to_buffers_with_timestamp(indio, st->buffer, pf->timestamp);
+static void at91_adc_trigger_handler_dma(struct iio_dev *indio_dev)
+{
+ struct at91_adc_state *st = iio_priv(indio_dev);
+ int transferred_len = at91_adc_dma_size_done(st);
+ s64 ns = iio_get_time_ns(indio_dev);
+ s64 interval;
+ int sample_index = 0, sample_count, sample_size;
+
+ u32 status = at91_adc_readl(st, AT91_SAMA5D2_ISR);
+ /* if we reached this point, we cannot sample faster */
+ if (status & AT91_SAMA5D2_IER_GOVRE)
+ pr_info_ratelimited("%s: conversion overrun detected\n",
+ indio_dev->name);
- iio_trigger_notify_done(indio->trig);
+ sample_size = div_s64(st->dma_st.rx_buf_sz, st->dma_st.watermark);
+
+ sample_count = div_s64(transferred_len, sample_size);
+
+ /*
+ * interval between samples is total time since last transfer handling
+ * divided by the number of samples (total size divided by sample size)
+ */
+ interval = div_s64((ns - st->dma_st.dma_ts), sample_count);
+
+ while (transferred_len >= sample_size) {
+ iio_push_to_buffers_with_timestamp(indio_dev,
+ (st->dma_st.rx_buf + st->dma_st.buf_idx),
+ (st->dma_st.dma_ts + interval * sample_index));
+ /* adjust remaining length */
+ transferred_len -= sample_size;
+ /* adjust buffer index */
+ st->dma_st.buf_idx += sample_size;
+ /* in case of reaching end of buffer, reset index */
+ if (st->dma_st.buf_idx >= st->dma_st.rx_buf_sz)
+ st->dma_st.buf_idx = 0;
+ sample_index++;
+ }
+ /* adjust saved time for next transfer handling */
+ st->dma_st.dma_ts = iio_get_time_ns(indio_dev);
+}
+
+static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct at91_adc_state *st = iio_priv(indio_dev);
+
+ if (st->dma_st.dma_chan)
+ at91_adc_trigger_handler_dma(indio_dev);
+ else
+ at91_adc_trigger_handler_nodma(indio_dev, pf);
+
+ iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
@@ -414,7 +657,7 @@ 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);
+ &at91_adc_trigger_handler, &at91_buffer_setup_ops);
}
static unsigned at91_adc_startup_time(unsigned startup_time_min,
@@ -485,10 +728,13 @@ static irqreturn_t at91_adc_interrupt(int irq, void *private)
if (!(status & imr))
return IRQ_NONE;
- if (iio_buffer_enabled(indio)) {
+ if (iio_buffer_enabled(indio) && !st->dma_st.dma_chan) {
disable_irq_nosync(irq);
iio_trigger_poll(indio->trig);
- } else {
+ } else if (iio_buffer_enabled(indio) && st->dma_st.dma_chan) {
+ disable_irq_nosync(irq);
+ WARN(true, "Unexpected irq occurred\n");
+ } else if (!iio_buffer_enabled(indio)) {
st->conversion_value = at91_adc_readl(st, st->chan->address);
st->conversion_done = true;
wake_up_interruptible(&st->wq_data_available);
@@ -510,7 +756,6 @@ static int at91_adc_read_raw(struct iio_dev *indio_dev,
ret = iio_device_claim_direct_mode(indio_dev);
if (ret)
return ret;
-
mutex_lock(&st->lock);
st->chan = chan;
@@ -541,6 +786,9 @@ static int at91_adc_read_raw(struct iio_dev *indio_dev,
at91_adc_writel(st, AT91_SAMA5D2_IDR, BIT(chan->channel));
at91_adc_writel(st, AT91_SAMA5D2_CHDR, BIT(chan->channel));
+ /* Needed to ACK the DRDY interruption */
+ at91_adc_readl(st, AT91_SAMA5D2_LCDR);
+
mutex_unlock(&st->lock);
iio_device_release_direct_mode(indio_dev);
@@ -580,9 +828,123 @@ static int at91_adc_write_raw(struct iio_dev *indio_dev,
return 0;
}
+static void at91_adc_dma_init(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+ struct at91_adc_state *st = iio_priv(indio_dev);
+ struct dma_slave_config config = {0};
+ /*
+ * We make the buffer double the size of the fifo,
+ * such that DMA uses one half of the buffer (full fifo size)
+ * and the software uses the other half to read/write.
+ */
+ unsigned int pages = DIV_ROUND_UP(AT91_HWFIFO_MAX_SIZE *
+ AT91_BUFFER_MAX_CONVERSION_BYTES * 2,
+ PAGE_SIZE);
+
+ if (st->dma_st.dma_chan)
+ return;
+
+ st->dma_st.dma_chan = dma_request_slave_channel(&pdev->dev, "rx");
+
+ if (!st->dma_st.dma_chan) {
+ dev_info(&pdev->dev, "can't get DMA channel\n");
+ goto dma_exit;
+ }
+
+ st->dma_st.rx_buf = dma_alloc_coherent(st->dma_st.dma_chan->device->dev,
+ pages * PAGE_SIZE,
+ &st->dma_st.rx_dma_buf,
+ GFP_KERNEL);
+ if (!st->dma_st.rx_buf) {
+ dev_info(&pdev->dev, "can't allocate coherent DMA area\n");
+ goto dma_chan_disable;
+ }
+
+ /* Configure DMA channel to read data register */
+ config.direction = DMA_DEV_TO_MEM;
+ config.src_addr = (phys_addr_t)(st->dma_st.phys_addr
+ + AT91_SAMA5D2_LCDR);
+ config.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
+ config.src_maxburst = 1;
+ config.dst_maxburst = 1;
+
+ if (dmaengine_slave_config(st->dma_st.dma_chan, &config)) {
+ dev_info(&pdev->dev, "can't configure DMA slave\n");
+ goto dma_free_area;
+ }
+
+ dev_info(&pdev->dev, "using %s for rx DMA transfers\n",
+ dma_chan_name(st->dma_st.dma_chan));
+
+ return;
+
+dma_free_area:
+ dma_free_coherent(st->dma_st.dma_chan->device->dev, pages * PAGE_SIZE,
+ st->dma_st.rx_buf, st->dma_st.rx_dma_buf);
+dma_chan_disable:
+ dma_release_channel(st->dma_st.dma_chan);
+ st->dma_st.dma_chan = 0;
+dma_exit:
+ dev_info(&pdev->dev, "continuing without DMA support\n");
+}
+
+static void at91_adc_dma_disable(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+ struct at91_adc_state *st = iio_priv(indio_dev);
+ unsigned int pages = DIV_ROUND_UP(AT91_HWFIFO_MAX_SIZE *
+ AT91_BUFFER_MAX_CONVERSION_BYTES * 2,
+ PAGE_SIZE);
+
+ /* if we are not using DMA, just return */
+ if (!st->dma_st.dma_chan)
+ return;
+
+ /* wait for all transactions to be terminated first*/
+ dmaengine_terminate_sync(st->dma_st.dma_chan);
+
+ dma_free_coherent(st->dma_st.dma_chan->device->dev, pages * PAGE_SIZE,
+ st->dma_st.rx_buf, st->dma_st.rx_dma_buf);
+ dma_release_channel(st->dma_st.dma_chan);
+ st->dma_st.dma_chan = 0;
+
+ dev_info(&pdev->dev, "continuing without DMA support\n");
+}
+
+static int at91_adc_set_watermark(struct iio_dev *indio_dev, unsigned int val)
+{
+ struct at91_adc_state *st = iio_priv(indio_dev);
+
+ if (val > AT91_HWFIFO_MAX_SIZE)
+ return -EINVAL;
+
+ if (!st->selected_trig->hw_trig) {
+ dev_dbg(&indio_dev->dev, "we need hw trigger for DMA\n");
+ return 0;
+ }
+
+ dev_dbg(&indio_dev->dev, "new watermark is %u\n", val);
+ st->dma_st.watermark = val;
+
+ /*
+ * The logic here is: if we have watermark 1, it means we do
+ * each conversion with it's own IRQ, thus we don't need DMA.
+ * If the watermark is higher, we do DMA to do all the transfers in bulk
+ */
+
+ if (val == 1)
+ at91_adc_dma_disable(to_platform_device(&indio_dev->dev));
+ else if (val > 1)
+ at91_adc_dma_init(to_platform_device(&indio_dev->dev));
+
+ return 0;
+}
+
static const struct iio_info at91_adc_info = {
.read_raw = &at91_adc_read_raw,
.write_raw = &at91_adc_write_raw,
+ .hwfifo_set_watermark = &at91_adc_set_watermark,
};
static void at91_adc_hw_init(struct at91_adc_state *st)
@@ -599,6 +961,42 @@ static void at91_adc_hw_init(struct at91_adc_state *st)
at91_adc_setup_samp_freq(st, st->soc_info.min_sample_rate);
}
+static ssize_t at91_adc_get_fifo_state(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct iio_dev *indio_dev =
+ platform_get_drvdata(to_platform_device(dev));
+ struct at91_adc_state *st = iio_priv(indio_dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%d\n", !!st->dma_st.dma_chan);
+}
+
+static ssize_t at91_adc_get_watermark(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct iio_dev *indio_dev =
+ platform_get_drvdata(to_platform_device(dev));
+ struct at91_adc_state *st = iio_priv(indio_dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%d\n", st->dma_st.watermark);
+}
+
+static IIO_DEVICE_ATTR(hwfifo_enabled, 0444,
+ at91_adc_get_fifo_state, NULL, 0);
+static IIO_DEVICE_ATTR(hwfifo_watermark, 0444,
+ at91_adc_get_watermark, NULL, 0);
+
+static IIO_CONST_ATTR(hwfifo_watermark_min, "2");
+static IIO_CONST_ATTR(hwfifo_watermark_max, AT91_HWFIFO_MAX_SIZE_STR);
+
+static const struct attribute *at91_adc_fifo_attributes[] = {
+ &iio_const_attr_hwfifo_watermark_min.dev_attr.attr,
+ &iio_const_attr_hwfifo_watermark_max.dev_attr.attr,
+ &iio_dev_attr_hwfifo_watermark.dev_attr.attr,
+ &iio_dev_attr_hwfifo_enabled.dev_attr.attr,
+ NULL,
+};
+
static int at91_adc_probe(struct platform_device *pdev)
{
struct iio_dev *indio_dev;
@@ -674,6 +1072,9 @@ static int at91_adc_probe(struct platform_device *pdev)
if (!res)
return -EINVAL;
+ /* if we plan to use DMA, we need the physical address of the regs */
+ st->dma_st.phys_addr = res->start;
+
st->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(st->base))
return PTR_ERR(st->base);
@@ -737,11 +1138,22 @@ static int at91_adc_probe(struct platform_device *pdev)
dev_err(&pdev->dev, "couldn't setup the triggers.\n");
goto per_clk_disable_unprepare;
}
+ /*
+ * Initially the iio buffer has a length of 2 and
+ * a watermark of 1
+ */
+ st->dma_st.watermark = 1;
+
+ iio_buffer_set_attrs(indio_dev->buffer,
+ at91_adc_fifo_attributes);
}
+ if (dma_coerce_mask_and_coherent(&indio_dev->dev, DMA_BIT_MASK(32)))
+ dev_info(&pdev->dev, "cannot set DMA mask to 32-bit\n");
+
ret = iio_device_register(indio_dev);
if (ret < 0)
- goto per_clk_disable_unprepare;
+ goto dma_disable;
if (st->selected_trig->hw_trig)
dev_info(&pdev->dev, "setting up trigger as %s\n",
@@ -752,6 +1164,8 @@ static int at91_adc_probe(struct platform_device *pdev)
return 0;
+dma_disable:
+ at91_adc_dma_disable(pdev);
per_clk_disable_unprepare:
clk_disable_unprepare(st->per_clk);
vref_disable:
@@ -768,6 +1182,8 @@ static int at91_adc_remove(struct platform_device *pdev)
iio_device_unregister(indio_dev);
+ at91_adc_dma_disable(pdev);
+
clk_disable_unprepare(st->per_clk);
regulator_disable(st->vref);
diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
index 3836d4222a3e..71a5ee652b79 100644
--- a/drivers/iio/adc/at91_adc.c
+++ b/drivers/iio/adc/at91_adc.c
@@ -1177,9 +1177,9 @@ static int at91_adc_probe(struct platform_device *pdev)
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
st->reg_base = devm_ioremap_resource(&pdev->dev, res);
- if (IS_ERR(st->reg_base)) {
+ if (IS_ERR(st->reg_base))
return PTR_ERR(st->reg_base);
- }
+
/*
* Disable all IRQs before setting up the handler
diff --git a/drivers/iio/adc/axp288_adc.c b/drivers/iio/adc/axp288_adc.c
index 60c9e853dd81..031d568b4972 100644
--- a/drivers/iio/adc/axp288_adc.c
+++ b/drivers/iio/adc/axp288_adc.c
@@ -92,22 +92,14 @@ static const struct iio_chan_spec axp288_adc_channels[] = {
},
};
-#define AXP288_ADC_MAP(_adc_channel_label, _consumer_dev_name, \
- _consumer_channel) \
- { \
- .adc_channel_label = _adc_channel_label, \
- .consumer_dev_name = _consumer_dev_name, \
- .consumer_channel = _consumer_channel, \
- }
-
/* for consumer drivers */
static struct iio_map axp288_adc_default_maps[] = {
- AXP288_ADC_MAP("TS_PIN", "axp288-batt", "axp288-batt-temp"),
- AXP288_ADC_MAP("PMIC_TEMP", "axp288-pmic", "axp288-pmic-temp"),
- AXP288_ADC_MAP("GPADC", "axp288-gpadc", "axp288-system-temp"),
- AXP288_ADC_MAP("BATT_CHG_I", "axp288-chrg", "axp288-chrg-curr"),
- AXP288_ADC_MAP("BATT_DISCHRG_I", "axp288-chrg", "axp288-chrg-d-curr"),
- AXP288_ADC_MAP("BATT_V", "axp288-batt", "axp288-batt-volt"),
+ IIO_MAP("TS_PIN", "axp288-batt", "axp288-batt-temp"),
+ IIO_MAP("PMIC_TEMP", "axp288-pmic", "axp288-pmic-temp"),
+ IIO_MAP("GPADC", "axp288-gpadc", "axp288-system-temp"),
+ IIO_MAP("BATT_CHG_I", "axp288-chrg", "axp288-chrg-curr"),
+ IIO_MAP("BATT_DISCHRG_I", "axp288-chrg", "axp288-chrg-d-curr"),
+ IIO_MAP("BATT_V", "axp288-batt", "axp288-batt-volt"),
{},
};
diff --git a/drivers/iio/adc/hx711.c b/drivers/iio/adc/hx711.c
index d10b9f13d557..9430b54121e0 100644
--- a/drivers/iio/adc/hx711.c
+++ b/drivers/iio/adc/hx711.c
@@ -24,6 +24,9 @@
#include <linux/delay.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
#include <linux/gpio/consumer.h>
#include <linux/regulator/consumer.h>
@@ -89,6 +92,11 @@ struct hx711_data {
int gain_set; /* gain set on device */
int gain_chan_a; /* gain for channel A */
struct mutex lock;
+ /*
+ * triggered buffer
+ * 2x32-bit channel + 64-bit timestamp
+ */
+ u32 buffer[4];
};
static int hx711_cycle(struct hx711_data *hx711_data)
@@ -145,15 +153,16 @@ static int hx711_wait_for_ready(struct hx711_data *hx711_data)
int i, val;
/*
- * a maximum reset cycle time of 56 ms was measured.
- * we round it up to 100 ms
+ * in some rare cases the reset takes quite a long time
+ * especially when the channel is changed.
+ * Allow up to one second for it
*/
for (i = 0; i < 100; i++) {
val = gpiod_get_value(hx711_data->gpiod_dout);
if (!val)
break;
- /* sleep at least 1 ms */
- msleep(1);
+ /* sleep at least 10 ms */
+ msleep(10);
}
if (val)
return -EIO;
@@ -195,9 +204,7 @@ static int hx711_reset(struct hx711_data *hx711_data)
* after a dummy read we need to wait vor readiness
* for not mixing gain pulses with the clock
*/
- ret = hx711_wait_for_ready(hx711_data);
- if (ret)
- return ret;
+ val = hx711_wait_for_ready(hx711_data);
}
return val;
@@ -236,34 +243,40 @@ static int hx711_set_gain_for_channel(struct hx711_data *hx711_data, int chan)
return 0;
}
+static int hx711_reset_read(struct hx711_data *hx711_data, int chan)
+{
+ int ret;
+ int val;
+
+ /*
+ * hx711_reset() must be called from here
+ * because it could be calling hx711_read() by itself
+ */
+ if (hx711_reset(hx711_data)) {
+ dev_err(hx711_data->dev, "reset failed!");
+ return -EIO;
+ }
+
+ ret = hx711_set_gain_for_channel(hx711_data, chan);
+ if (ret < 0)
+ return ret;
+
+ val = hx711_read(hx711_data);
+
+ return val;
+}
+
static int hx711_read_raw(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
int *val, int *val2, long mask)
{
struct hx711_data *hx711_data = iio_priv(indio_dev);
- int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
mutex_lock(&hx711_data->lock);
- /*
- * hx711_reset() must be called from here
- * because it could be calling hx711_read() by itself
- */
- if (hx711_reset(hx711_data)) {
- mutex_unlock(&hx711_data->lock);
- dev_err(hx711_data->dev, "reset failed!");
- return -EIO;
- }
-
- ret = hx711_set_gain_for_channel(hx711_data, chan->channel);
- if (ret < 0) {
- mutex_unlock(&hx711_data->lock);
- return ret;
- }
-
- *val = hx711_read(hx711_data);
+ *val = hx711_reset_read(hx711_data, chan->channel);
mutex_unlock(&hx711_data->lock);
@@ -339,6 +352,36 @@ static int hx711_write_raw_get_fmt(struct iio_dev *indio_dev,
return IIO_VAL_INT_PLUS_NANO;
}
+static irqreturn_t hx711_trigger(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct hx711_data *hx711_data = iio_priv(indio_dev);
+ int i, j = 0;
+
+ mutex_lock(&hx711_data->lock);
+
+ memset(hx711_data->buffer, 0, sizeof(hx711_data->buffer));
+
+ for (i = 0; i < indio_dev->masklength; i++) {
+ if (!test_bit(i, indio_dev->active_scan_mask))
+ continue;
+
+ hx711_data->buffer[j] = hx711_reset_read(hx711_data,
+ indio_dev->channels[i].channel);
+ j++;
+ }
+
+ iio_push_to_buffers_with_timestamp(indio_dev, hx711_data->buffer,
+ pf->timestamp);
+
+ mutex_unlock(&hx711_data->lock);
+
+ iio_trigger_notify_done(indio_dev->trig);
+
+ return IRQ_HANDLED;
+}
+
static ssize_t hx711_scale_available_show(struct device *dev,
struct device_attribute *attr,
char *buf)
@@ -387,6 +430,13 @@ static const struct iio_chan_spec hx711_chan_spec[] = {
.indexed = 1,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
+ .scan_index = 0,
+ .scan_type = {
+ .sign = 'u',
+ .realbits = 24,
+ .storagebits = 32,
+ .endianness = IIO_CPU,
+ },
},
{
.type = IIO_VOLTAGE,
@@ -394,7 +444,15 @@ static const struct iio_chan_spec hx711_chan_spec[] = {
.indexed = 1,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
+ .scan_index = 1,
+ .scan_type = {
+ .sign = 'u',
+ .realbits = 24,
+ .storagebits = 32,
+ .endianness = IIO_CPU,
+ },
},
+ IIO_CHAN_SOFT_TIMESTAMP(2),
};
static int hx711_probe(struct platform_device *pdev)
@@ -459,10 +517,9 @@ static int hx711_probe(struct platform_device *pdev)
* 1 LSB = (AVDD * 100) / GAIN / 1678 [10^-9 mV]
*/
ret = regulator_get_voltage(hx711_data->reg_avdd);
- if (ret < 0) {
- regulator_disable(hx711_data->reg_avdd);
- return ret;
- }
+ if (ret < 0)
+ goto error_regulator;
+
/* we need 10^-9 mV */
ret *= 100;
@@ -482,12 +539,27 @@ static int hx711_probe(struct platform_device *pdev)
indio_dev->channels = hx711_chan_spec;
indio_dev->num_channels = ARRAY_SIZE(hx711_chan_spec);
+ ret = iio_triggered_buffer_setup(indio_dev, iio_pollfunc_store_time,
+ hx711_trigger, NULL);
+ if (ret < 0) {
+ dev_err(dev, "setup of iio triggered buffer failed\n");
+ goto error_regulator;
+ }
+
ret = iio_device_register(indio_dev);
if (ret < 0) {
dev_err(dev, "Couldn't register the device\n");
- regulator_disable(hx711_data->reg_avdd);
+ goto error_buffer;
}
+ return 0;
+
+error_buffer:
+ iio_triggered_buffer_cleanup(indio_dev);
+
+error_regulator:
+ regulator_disable(hx711_data->reg_avdd);
+
return ret;
}
@@ -501,6 +573,8 @@ static int hx711_remove(struct platform_device *pdev)
iio_device_unregister(indio_dev);
+ iio_triggered_buffer_cleanup(indio_dev);
+
regulator_disable(hx711_data->reg_avdd);
return 0;
diff --git a/drivers/iio/adc/ina2xx-adc.c b/drivers/iio/adc/ina2xx-adc.c
index 84a43871f7dc..0635a79864bf 100644
--- a/drivers/iio/adc/ina2xx-adc.c
+++ b/drivers/iio/adc/ina2xx-adc.c
@@ -44,13 +44,14 @@
#define INA226_MASK_ENABLE 0x06
#define INA226_CVRF BIT(3)
-#define INA219_CNVR BIT(1)
#define INA2XX_MAX_REGISTERS 8
/* settings - depend on use case */
-#define INA219_CONFIG_DEFAULT 0x399F /* PGA=8 */
+#define INA219_CONFIG_DEFAULT 0x399F /* PGA=1/8, BRNG=32V */
#define INA219_DEFAULT_IT 532
+#define INA219_DEFAULT_BRNG 1 /* 32V */
+#define INA219_DEFAULT_PGA 125 /* 1000/8 */
#define INA226_CONFIG_DEFAULT 0x4327
#define INA226_DEFAULT_AVG 4
#define INA226_DEFAULT_IT 1110
@@ -63,6 +64,14 @@
*/
#define INA2XX_MODE_MASK GENMASK(3, 0)
+/* Gain for VShunt: 1/8 (default), 1/4, 1/2, 1 */
+#define INA219_PGA_MASK GENMASK(12, 11)
+#define INA219_SHIFT_PGA(val) ((val) << 11)
+
+/* VBus range: 32V (default), 16V */
+#define INA219_BRNG_MASK BIT(13)
+#define INA219_SHIFT_BRNG(val) ((val) << 13)
+
/* Averaging for VBus/VShunt/Power */
#define INA226_AVG_MASK GENMASK(11, 9)
#define INA226_SHIFT_AVG(val) ((val) << 9)
@@ -79,6 +88,11 @@
#define INA226_ITS_MASK GENMASK(5, 3)
#define INA226_SHIFT_ITS(val) ((val) << 3)
+/* INA219 Bus voltage register, low bits are flags */
+#define INA219_OVF BIT(0)
+#define INA219_CNVR BIT(1)
+#define INA219_BUS_VOLTAGE_SHIFT 3
+
/* Cosmetic macro giving the sampling period for a full P=UxI cycle */
#define SAMPLING_PERIOD(c) ((c->int_time_vbus + c->int_time_vshunt) \
* c->avg)
@@ -110,11 +124,12 @@ enum ina2xx_ids { ina219, ina226 };
struct ina2xx_config {
u16 config_default;
- int calibration_factor;
- int shunt_div;
- int bus_voltage_shift;
+ int calibration_value;
+ int shunt_voltage_lsb; /* nV */
+ int bus_voltage_shift; /* position of lsb */
int bus_voltage_lsb; /* uV */
- int power_lsb; /* uW */
+ /* fixed relation between current and power lsb, uW/uA */
+ int power_lsb_factor;
enum ina2xx_ids chip_id;
};
@@ -127,26 +142,28 @@ struct ina2xx_chip_info {
int avg;
int int_time_vbus; /* Bus voltage integration time uS */
int int_time_vshunt; /* Shunt voltage integration time uS */
+ int range_vbus; /* Bus voltage maximum in V */
+ int pga_gain_vshunt; /* Shunt voltage PGA gain */
bool allow_async_readout;
};
static const struct ina2xx_config ina2xx_config[] = {
[ina219] = {
.config_default = INA219_CONFIG_DEFAULT,
- .calibration_factor = 40960000,
- .shunt_div = 100,
- .bus_voltage_shift = 3,
+ .calibration_value = 4096,
+ .shunt_voltage_lsb = 10000,
+ .bus_voltage_shift = INA219_BUS_VOLTAGE_SHIFT,
.bus_voltage_lsb = 4000,
- .power_lsb = 20000,
+ .power_lsb_factor = 20,
.chip_id = ina219,
},
[ina226] = {
.config_default = INA226_CONFIG_DEFAULT,
- .calibration_factor = 5120000,
- .shunt_div = 400,
+ .calibration_value = 2048,
+ .shunt_voltage_lsb = 2500,
.bus_voltage_shift = 0,
.bus_voltage_lsb = 1250,
- .power_lsb = 25000,
+ .power_lsb_factor = 25,
.chip_id = ina226,
},
};
@@ -170,6 +187,9 @@ static int ina2xx_read_raw(struct iio_dev *indio_dev,
else
*val = regval;
+ if (chan->address == INA2XX_BUS_VOLTAGE)
+ *val >>= chip->config->bus_voltage_shift;
+
return IIO_VAL_INT;
case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
@@ -197,26 +217,48 @@ static int ina2xx_read_raw(struct iio_dev *indio_dev,
case IIO_CHAN_INFO_SCALE:
switch (chan->address) {
case INA2XX_SHUNT_VOLTAGE:
- /* processed (mV) = raw/shunt_div */
- *val2 = chip->config->shunt_div;
- *val = 1;
+ /* processed (mV) = raw * lsb(nV) / 1000000 */
+ *val = chip->config->shunt_voltage_lsb;
+ *val2 = 1000000;
return IIO_VAL_FRACTIONAL;
case INA2XX_BUS_VOLTAGE:
- /* processed (mV) = raw*lsb (uV) / (1000 << shift) */
+ /* processed (mV) = raw * lsb (uV) / 1000 */
*val = chip->config->bus_voltage_lsb;
- *val2 = 1000 << chip->config->bus_voltage_shift;
+ *val2 = 1000;
+ return IIO_VAL_FRACTIONAL;
+
+ case INA2XX_CURRENT:
+ /*
+ * processed (mA) = raw * current_lsb (mA)
+ * current_lsb (mA) = shunt_voltage_lsb (nV) /
+ * shunt_resistor (uOhm)
+ */
+ *val = chip->config->shunt_voltage_lsb;
+ *val2 = chip->shunt_resistor_uohm;
return IIO_VAL_FRACTIONAL;
case INA2XX_POWER:
- /* processed (mW) = raw*lsb (uW) / 1000 */
- *val = chip->config->power_lsb;
+ /*
+ * processed (mW) = raw * power_lsb (mW)
+ * power_lsb (mW) = power_lsb_factor (mW/mA) *
+ * current_lsb (mA)
+ */
+ *val = chip->config->power_lsb_factor *
+ chip->config->shunt_voltage_lsb;
+ *val2 = chip->shunt_resistor_uohm;
+ return IIO_VAL_FRACTIONAL;
+ }
+
+ case IIO_CHAN_INFO_HARDWAREGAIN:
+ switch (chan->address) {
+ case INA2XX_SHUNT_VOLTAGE:
+ *val = chip->pga_gain_vshunt;
*val2 = 1000;
return IIO_VAL_FRACTIONAL;
- case INA2XX_CURRENT:
- /* processed (mA) = raw (mA) */
- *val = 1;
+ case INA2XX_BUS_VOLTAGE:
+ *val = chip->range_vbus == 32 ? 1 : 2;
return IIO_VAL_INT;
}
}
@@ -353,6 +395,74 @@ static int ina219_set_int_time_vshunt(struct ina2xx_chip_info *chip,
return 0;
}
+static const int ina219_vbus_range_tab[] = { 1, 2 };
+static int ina219_set_vbus_range_denom(struct ina2xx_chip_info *chip,
+ unsigned int range,
+ unsigned int *config)
+{
+ if (range == 1)
+ chip->range_vbus = 32;
+ else if (range == 2)
+ chip->range_vbus = 16;
+ else
+ return -EINVAL;
+
+ *config &= ~INA219_BRNG_MASK;
+ *config |= INA219_SHIFT_BRNG(range == 1 ? 1 : 0) & INA219_BRNG_MASK;
+
+ return 0;
+}
+
+static const int ina219_vshunt_gain_tab[] = { 125, 250, 500, 1000 };
+static const int ina219_vshunt_gain_frac[] = {
+ 125, 1000, 250, 1000, 500, 1000, 1000, 1000 };
+
+static int ina219_set_vshunt_pga_gain(struct ina2xx_chip_info *chip,
+ unsigned int gain,
+ unsigned int *config)
+{
+ int bits;
+
+ if (gain < 125 || gain > 1000)
+ return -EINVAL;
+
+ bits = find_closest(gain, ina219_vshunt_gain_tab,
+ ARRAY_SIZE(ina219_vshunt_gain_tab));
+
+ chip->pga_gain_vshunt = ina219_vshunt_gain_tab[bits];
+ bits = 3 - bits;
+
+ *config &= ~INA219_PGA_MASK;
+ *config |= INA219_SHIFT_PGA(bits) & INA219_PGA_MASK;
+
+ return 0;
+}
+
+static int ina2xx_read_avail(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ const int **vals, int *type, int *length,
+ long mask)
+{
+ switch (mask) {
+ case IIO_CHAN_INFO_HARDWAREGAIN:
+ switch (chan->address) {
+ case INA2XX_SHUNT_VOLTAGE:
+ *type = IIO_VAL_FRACTIONAL;
+ *length = sizeof(ina219_vshunt_gain_frac) / sizeof(int);
+ *vals = ina219_vshunt_gain_frac;
+ return IIO_AVAIL_LIST;
+
+ case INA2XX_BUS_VOLTAGE:
+ *type = IIO_VAL_INT;
+ *length = sizeof(ina219_vbus_range_tab) / sizeof(int);
+ *vals = ina219_vbus_range_tab;
+ return IIO_AVAIL_LIST;
+ }
+ }
+
+ return -EINVAL;
+}
+
static int ina2xx_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
@@ -395,6 +505,14 @@ static int ina2xx_write_raw(struct iio_dev *indio_dev,
}
break;
+ case IIO_CHAN_INFO_HARDWAREGAIN:
+ if (chan->address == INA2XX_SHUNT_VOLTAGE)
+ ret = ina219_set_vshunt_pga_gain(chip, val * 1000 +
+ val2 / 1000, &tmp);
+ else
+ ret = ina219_set_vbus_range_denom(chip, val, &tmp);
+ break;
+
default:
ret = -EINVAL;
}
@@ -434,25 +552,21 @@ static ssize_t ina2xx_allow_async_readout_store(struct device *dev,
}
/*
- * Set current LSB to 1mA, shunt is in uOhms
- * (equation 13 in datasheet). We hardcode a Current_LSB
- * of 1.0 x10-3. The only remaining parameter is RShunt.
- * There is no need to expose the CALIBRATION register
- * to the user for now. But we need to reset this register
- * if the user updates RShunt after driver init, e.g upon
- * reading an EEPROM/Probe-type value.
+ * Calibration register is set to the best value, which eliminates
+ * truncation errors on calculating current register in hardware.
+ * According to datasheet (INA 226: eq. 3, INA219: eq. 4) the best values
+ * are 2048 for ina226 and 4096 for ina219. They are hardcoded as
+ * calibration_value.
*/
static int ina2xx_set_calibration(struct ina2xx_chip_info *chip)
{
- u16 regval = DIV_ROUND_CLOSEST(chip->config->calibration_factor,
- chip->shunt_resistor_uohm);
-
- return regmap_write(chip->regmap, INA2XX_CALIBRATION, regval);
+ return regmap_write(chip->regmap, INA2XX_CALIBRATION,
+ chip->config->calibration_value);
}
static int set_shunt_resistor(struct ina2xx_chip_info *chip, unsigned int val)
{
- if (val <= 0 || val > chip->config->calibration_factor)
+ if (val == 0 || val > INT_MAX)
return -EINVAL;
chip->shunt_resistor_uohm = val;
@@ -485,11 +599,6 @@ static ssize_t ina2xx_shunt_resistor_store(struct device *dev,
if (ret)
return ret;
- /* Update the Calibration register */
- ret = ina2xx_set_calibration(chip);
- if (ret)
- return ret;
-
return len;
}
@@ -532,19 +641,23 @@ static ssize_t ina2xx_shunt_resistor_store(struct device *dev,
* Sampling Freq is a consequence of the integration times of
* the Voltage channels.
*/
-#define INA219_CHAN_VOLTAGE(_index, _address) { \
+#define INA219_CHAN_VOLTAGE(_index, _address, _shift) { \
.type = IIO_VOLTAGE, \
.address = (_address), \
.indexed = 1, \
.channel = (_index), \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_SCALE) | \
- BIT(IIO_CHAN_INFO_INT_TIME), \
+ BIT(IIO_CHAN_INFO_INT_TIME) | \
+ BIT(IIO_CHAN_INFO_HARDWAREGAIN), \
+ .info_mask_separate_available = \
+ BIT(IIO_CHAN_INFO_HARDWAREGAIN), \
.info_mask_shared_by_dir = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
.scan_index = (_index), \
.scan_type = { \
.sign = 'u', \
- .realbits = 16, \
+ .shift = _shift, \
+ .realbits = 16 - _shift, \
.storagebits = 16, \
.endianness = IIO_LE, \
} \
@@ -579,23 +692,18 @@ static const struct iio_chan_spec ina226_channels[] = {
};
static const struct iio_chan_spec ina219_channels[] = {
- INA219_CHAN_VOLTAGE(0, INA2XX_SHUNT_VOLTAGE),
- INA219_CHAN_VOLTAGE(1, INA2XX_BUS_VOLTAGE),
+ INA219_CHAN_VOLTAGE(0, INA2XX_SHUNT_VOLTAGE, 0),
+ INA219_CHAN_VOLTAGE(1, INA2XX_BUS_VOLTAGE, INA219_BUS_VOLTAGE_SHIFT),
INA219_CHAN(IIO_POWER, 2, INA2XX_POWER),
INA219_CHAN(IIO_CURRENT, 3, INA2XX_CURRENT),
IIO_CHAN_SOFT_TIMESTAMP(4),
};
-static int ina2xx_work_buffer(struct iio_dev *indio_dev)
+static int ina2xx_conversion_ready(struct iio_dev *indio_dev)
{
struct ina2xx_chip_info *chip = iio_priv(indio_dev);
- unsigned short data[8];
- int bit, ret, i = 0;
- s64 time_a, time_b;
+ int ret;
unsigned int alert;
- int cnvr_need_clear = 0;
-
- time_a = iio_get_time_ns(indio_dev);
/*
* Because the timer thread and the chip conversion clock
@@ -608,23 +716,31 @@ static int ina2xx_work_buffer(struct iio_dev *indio_dev)
* For now, we do an extra read of the MASK_ENABLE register (INA226)
* resp. the BUS_VOLTAGE register (INA219).
*/
- if (!chip->allow_async_readout)
- do {
- if (chip->config->chip_id == ina226) {
- ret = regmap_read(chip->regmap,
- INA226_MASK_ENABLE, &alert);
- alert &= INA226_CVRF;
- } else {
- ret = regmap_read(chip->regmap,
- INA2XX_BUS_VOLTAGE, &alert);
- alert &= INA219_CNVR;
- cnvr_need_clear = alert;
- }
+ if (chip->config->chip_id == ina226) {
+ ret = regmap_read(chip->regmap,
+ INA226_MASK_ENABLE, &alert);
+ alert &= INA226_CVRF;
+ } else {
+ ret = regmap_read(chip->regmap,
+ INA2XX_BUS_VOLTAGE, &alert);
+ alert &= INA219_CNVR;
+ }
- if (ret < 0)
- return ret;
+ if (ret < 0)
+ return ret;
+
+ return !!alert;
+}
+
+static int ina2xx_work_buffer(struct iio_dev *indio_dev)
+{
+ struct ina2xx_chip_info *chip = iio_priv(indio_dev);
+ /* data buffer needs space for channel data and timestap */
+ unsigned short data[4 + sizeof(s64)/sizeof(short)];
+ int bit, ret, i = 0;
+ s64 time;
- } while (!alert);
+ time = iio_get_time_ns(indio_dev);
/*
* Single register reads: bulk_read will not work with ina226/219
@@ -640,26 +756,11 @@ static int ina2xx_work_buffer(struct iio_dev *indio_dev)
return ret;
data[i++] = val;
-
- if (INA2XX_SHUNT_VOLTAGE + bit == INA2XX_POWER)
- cnvr_need_clear = 0;
- }
-
- /* Dummy read on INA219 power register to clear CNVR flag */
- if (cnvr_need_clear && chip->config->chip_id == ina219) {
- unsigned int val;
-
- ret = regmap_read(chip->regmap, INA2XX_POWER, &val);
- if (ret < 0)
- return ret;
}
- time_b = iio_get_time_ns(indio_dev);
+ iio_push_to_buffers_with_timestamp(indio_dev, data, time);
- iio_push_to_buffers_with_timestamp(indio_dev,
- (unsigned int *)data, time_a);
-
- return (unsigned long)(time_b - time_a) / 1000;
+ return 0;
};
static int ina2xx_capture_thread(void *data)
@@ -667,7 +768,9 @@ static int ina2xx_capture_thread(void *data)
struct iio_dev *indio_dev = data;
struct ina2xx_chip_info *chip = iio_priv(indio_dev);
int sampling_us = SAMPLING_PERIOD(chip);
- int buffer_us;
+ int ret;
+ struct timespec64 next, now, delta;
+ s64 delay_us;
/*
* Poll a bit faster than the chip internal Fs, in case
@@ -676,13 +779,43 @@ static int ina2xx_capture_thread(void *data)
if (!chip->allow_async_readout)
sampling_us -= 200;
+ ktime_get_ts64(&next);
+
do {
- buffer_us = ina2xx_work_buffer(indio_dev);
- if (buffer_us < 0)
- return buffer_us;
+ while (!chip->allow_async_readout) {
+ ret = ina2xx_conversion_ready(indio_dev);
+ if (ret < 0)
+ return ret;
- if (sampling_us > buffer_us)
- udelay(sampling_us - buffer_us);
+ /*
+ * If the conversion was not yet finished,
+ * reset the reference timestamp.
+ */
+ if (ret == 0)
+ ktime_get_ts64(&next);
+ else
+ break;
+ }
+
+ ret = ina2xx_work_buffer(indio_dev);
+ if (ret < 0)
+ return ret;
+
+ ktime_get_ts64(&now);
+
+ /*
+ * Advance the timestamp for the next poll by one sampling
+ * interval, and sleep for the remainder (next - now)
+ * In case "next" has already passed, the interval is added
+ * multiple times, i.e. samples are dropped.
+ */
+ do {
+ timespec64_add_ns(&next, 1000 * sampling_us);
+ delta = timespec64_sub(next, now);
+ delay_us = div_s64(timespec64_to_ns(&delta), 1000);
+ } while (delay_us <= 0);
+
+ usleep_range(delay_us, (delay_us * 3) >> 1);
} while (!kthread_should_stop());
@@ -746,7 +879,6 @@ static IIO_CONST_ATTR_NAMED(ina226_integration_time_available,
integration_time_available,
"0.000140 0.000204 0.000332 0.000588 0.001100 0.002116 0.004156 0.008244");
-
static IIO_DEVICE_ATTR(in_allow_async_readout, S_IRUGO | S_IWUSR,
ina2xx_allow_async_readout_show,
ina2xx_allow_async_readout_store, 0);
@@ -780,6 +912,7 @@ static const struct attribute_group ina226_attribute_group = {
static const struct iio_info ina219_info = {
.attrs = &ina219_attribute_group,
.read_raw = ina2xx_read_raw,
+ .read_avail = ina2xx_read_avail,
.write_raw = ina2xx_write_raw,
.debugfs_reg_access = ina2xx_debug_reg,
};
@@ -860,6 +993,8 @@ static int ina2xx_probe(struct i2c_client *client,
chip->avg = 1;
ina219_set_int_time_vbus(chip, INA219_DEFAULT_IT, &val);
ina219_set_int_time_vshunt(chip, INA219_DEFAULT_IT, &val);
+ ina219_set_vbus_range_denom(chip, INA219_DEFAULT_BRNG, &val);
+ ina219_set_vshunt_pga_gain(chip, INA219_DEFAULT_PGA, &val);
}
ret = ina2xx_init(chip, val);
diff --git a/drivers/iio/adc/meson_saradc.c b/drivers/iio/adc/meson_saradc.c
index 36047147ce7c..29fa7736d80c 100644
--- a/drivers/iio/adc/meson_saradc.c
+++ b/drivers/iio/adc/meson_saradc.c
@@ -96,8 +96,8 @@
#define MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK GENMASK(11, 0)
#define MESON_SAR_ADC_AUX_SW 0x1c
- #define MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_MASK(_chan) \
- (GENMASK(10, 8) << (((_chan) - 2) * 2))
+ #define MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_SHIFT(_chan) \
+ (8 + (((_chan) - 2) * 3))
#define MESON_SAR_ADC_AUX_SW_VREF_P_MUX BIT(6)
#define MESON_SAR_ADC_AUX_SW_VREF_N_MUX BIT(5)
#define MESON_SAR_ADC_AUX_SW_MODE_SEL BIT(4)
@@ -221,6 +221,7 @@ enum meson_sar_adc_chan7_mux_sel {
struct meson_sar_adc_data {
bool has_bl30_integration;
+ unsigned long clock_rate;
u32 bandgap_reg;
unsigned int resolution;
const char *name;
@@ -233,7 +234,6 @@ struct meson_sar_adc_priv {
const struct meson_sar_adc_data *data;
struct clk *clkin;
struct clk *core_clk;
- struct clk *sana_clk;
struct clk *adc_sel_clk;
struct clk *adc_clk;
struct clk_gate clk_gate;
@@ -622,7 +622,7 @@ static int meson_sar_adc_clk_init(struct iio_dev *indio_dev,
static int meson_sar_adc_init(struct iio_dev *indio_dev)
{
struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
- int regval, ret;
+ int regval, i, ret;
/*
* make sure we start at CH7 input since the other muxes are only used
@@ -677,6 +677,32 @@ static int meson_sar_adc_init(struct iio_dev *indio_dev)
FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK,
1));
+ /*
+ * set up the input channel muxes in MESON_SAR_ADC_CHAN_10_SW
+ * (0 = SAR_ADC_CH0, 1 = SAR_ADC_CH1)
+ */
+ regval = FIELD_PREP(MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK, 0);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
+ MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK,
+ regval);
+ regval = FIELD_PREP(MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK, 1);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
+ MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK,
+ regval);
+
+ /*
+ * set up the input channel muxes in MESON_SAR_ADC_AUX_SW
+ * (2 = SAR_ADC_CH2, 3 = SAR_ADC_CH3, ...) and enable
+ * MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW and
+ * MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW like the vendor driver.
+ */
+ regval = 0;
+ for (i = 2; i <= 7; i++)
+ regval |= i << MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_SHIFT(i);
+ regval |= MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW;
+ regval |= MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW;
+ regmap_write(priv->regmap, MESON_SAR_ADC_AUX_SW, regval);
+
ret = clk_set_parent(priv->adc_sel_clk, priv->clkin);
if (ret) {
dev_err(indio_dev->dev.parent,
@@ -684,7 +710,7 @@ static int meson_sar_adc_init(struct iio_dev *indio_dev)
return ret;
}
- ret = clk_set_rate(priv->adc_clk, 1200000);
+ ret = clk_set_rate(priv->adc_clk, priv->data->clock_rate);
if (ret) {
dev_err(indio_dev->dev.parent,
"failed to set adc clock rate\n");
@@ -731,12 +757,6 @@ static int meson_sar_adc_hw_enable(struct iio_dev *indio_dev)
goto err_core_clk;
}
- ret = clk_prepare_enable(priv->sana_clk);
- if (ret) {
- dev_err(indio_dev->dev.parent, "failed to enable sana clk\n");
- goto err_sana_clk;
- }
-
regval = FIELD_PREP(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, 1);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
@@ -763,8 +783,6 @@ err_adc_clk:
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
MESON_SAR_ADC_REG3_ADC_EN, 0);
meson_sar_adc_set_bandgap(indio_dev, false);
- clk_disable_unprepare(priv->sana_clk);
-err_sana_clk:
clk_disable_unprepare(priv->core_clk);
err_core_clk:
regulator_disable(priv->vref);
@@ -790,7 +808,6 @@ static int meson_sar_adc_hw_disable(struct iio_dev *indio_dev)
meson_sar_adc_set_bandgap(indio_dev, false);
- clk_disable_unprepare(priv->sana_clk);
clk_disable_unprepare(priv->core_clk);
regulator_disable(priv->vref);
@@ -866,6 +883,7 @@ static const struct iio_info meson_sar_adc_iio_info = {
static const struct meson_sar_adc_data meson_sar_adc_meson8_data = {
.has_bl30_integration = false,
+ .clock_rate = 1150000,
.bandgap_reg = MESON_SAR_ADC_DELTA_10,
.regmap_config = &meson_sar_adc_regmap_config_meson8,
.resolution = 10,
@@ -874,6 +892,7 @@ static const struct meson_sar_adc_data meson_sar_adc_meson8_data = {
static const struct meson_sar_adc_data meson_sar_adc_meson8b_data = {
.has_bl30_integration = false,
+ .clock_rate = 1150000,
.bandgap_reg = MESON_SAR_ADC_DELTA_10,
.regmap_config = &meson_sar_adc_regmap_config_meson8,
.resolution = 10,
@@ -882,6 +901,7 @@ static const struct meson_sar_adc_data meson_sar_adc_meson8b_data = {
static const struct meson_sar_adc_data meson_sar_adc_gxbb_data = {
.has_bl30_integration = true,
+ .clock_rate = 1200000,
.bandgap_reg = MESON_SAR_ADC_REG11,
.regmap_config = &meson_sar_adc_regmap_config_gxbb,
.resolution = 10,
@@ -890,6 +910,7 @@ static const struct meson_sar_adc_data meson_sar_adc_gxbb_data = {
static const struct meson_sar_adc_data meson_sar_adc_gxl_data = {
.has_bl30_integration = true,
+ .clock_rate = 1200000,
.bandgap_reg = MESON_SAR_ADC_REG11,
.regmap_config = &meson_sar_adc_regmap_config_gxbb,
.resolution = 12,
@@ -898,6 +919,7 @@ static const struct meson_sar_adc_data meson_sar_adc_gxl_data = {
static const struct meson_sar_adc_data meson_sar_adc_gxm_data = {
.has_bl30_integration = true,
+ .clock_rate = 1200000,
.bandgap_reg = MESON_SAR_ADC_REG11,
.regmap_config = &meson_sar_adc_regmap_config_gxbb,
.resolution = 12,
@@ -993,16 +1015,6 @@ static int meson_sar_adc_probe(struct platform_device *pdev)
return PTR_ERR(priv->core_clk);
}
- priv->sana_clk = devm_clk_get(&pdev->dev, "sana");
- if (IS_ERR(priv->sana_clk)) {
- if (PTR_ERR(priv->sana_clk) == -ENOENT) {
- priv->sana_clk = NULL;
- } else {
- dev_err(&pdev->dev, "failed to get sana clk\n");
- return PTR_ERR(priv->sana_clk);
- }
- }
-
priv->adc_clk = devm_clk_get(&pdev->dev, "adc_clk");
if (IS_ERR(priv->adc_clk)) {
if (PTR_ERR(priv->adc_clk) == -ENOENT) {
diff --git a/drivers/iio/adc/qcom-vadc-common.c b/drivers/iio/adc/qcom-vadc-common.c
index 47d24ae5462f..fe3d7826783c 100644
--- a/drivers/iio/adc/qcom-vadc-common.c
+++ b/drivers/iio/adc/qcom-vadc-common.c
@@ -5,6 +5,7 @@
#include <linux/math64.h>
#include <linux/log2.h>
#include <linux/err.h>
+#include <linux/module.h>
#include "qcom-vadc-common.h"
@@ -229,3 +230,6 @@ int qcom_vadc_decimation_from_dt(u32 value)
return __ffs64(value / VADC_DECIMATION_MIN);
}
EXPORT_SYMBOL(qcom_vadc_decimation_from_dt);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Qualcomm ADC common functionality");
diff --git a/drivers/iio/adc/stm32-adc-core.c b/drivers/iio/adc/stm32-adc-core.c
index 6aefef99f935..40be7d9fadbf 100644
--- a/drivers/iio/adc/stm32-adc-core.c
+++ b/drivers/iio/adc/stm32-adc-core.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
/*
* This file is part of STM32 ADC driver
*
@@ -6,19 +7,6 @@
*
* Inspired from: fsl-imx25-tsadc
*
- * License type: GPLv2
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published by
- * the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
- * or FITNESS FOR A PARTICULAR PURPOSE.
- * See the GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/clk.h>
diff --git a/drivers/iio/adc/stm32-adc-core.h b/drivers/iio/adc/stm32-adc-core.h
index 250ee958a669..8af507b3f32d 100644
--- a/drivers/iio/adc/stm32-adc-core.h
+++ b/drivers/iio/adc/stm32-adc-core.h
@@ -1,22 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0 */
/*
* This file is part of STM32 ADC driver
*
* Copyright (C) 2016, STMicroelectronics - All Rights Reserved
* Author: Fabrice Gasnier <fabrice.gasnier@st.com>.
*
- * License type: GPLv2
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published by
- * the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
- * or FITNESS FOR A PARTICULAR PURPOSE.
- * See the GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __STM32_ADC_H
diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c
index c9d96f935dba..7f5def465340 100644
--- a/drivers/iio/adc/stm32-adc.c
+++ b/drivers/iio/adc/stm32-adc.c
@@ -1,22 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0
/*
* This file is part of STM32 ADC driver
*
* Copyright (C) 2016, STMicroelectronics - All Rights Reserved
* Author: Fabrice Gasnier <fabrice.gasnier@st.com>.
- *
- * License type: GPLv2
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published by
- * the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
- * or FITNESS FOR A PARTICULAR PURPOSE.
- * See the GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/clk.h>
@@ -92,6 +79,7 @@
#define STM32H7_ADC_SQR3 0x38
#define STM32H7_ADC_SQR4 0x3C
#define STM32H7_ADC_DR 0x40
+#define STM32H7_ADC_DIFSEL 0xC0
#define STM32H7_ADC_CALFACT 0xC4
#define STM32H7_ADC_CALFACT2 0xC8
@@ -153,6 +141,8 @@ enum stm32h7_adc_dmngt {
/* BOOST bit must be set on STM32H7 when ADC clock is above 20MHz */
#define STM32H7_BOOST_CLKRATE 20000000UL
+#define STM32_ADC_CH_MAX 20 /* max number of channels */
+#define STM32_ADC_CH_SZ 10 /* max channel name size */
#define STM32_ADC_MAX_SQ 16 /* SQ1..SQ16 */
#define STM32_ADC_MAX_SMP 7 /* SMPx range is [0..7] */
#define STM32_ADC_TIMEOUT_US 100000
@@ -297,9 +287,11 @@ struct stm32_adc_cfg {
* @rx_buf: dma rx buffer cpu address
* @rx_dma_buf: dma rx buffer bus address
* @rx_buf_sz: dma rx buffer size
+ * @difsel bitmask to set single-ended/differential channel
* @pcsel bitmask to preselect channels on some devices
* @smpr_val: sampling time settings (e.g. smpr1 / smpr2)
* @cal: optional calibration data on some devices
+ * @chan_name: channel name array
*/
struct stm32_adc {
struct stm32_adc_common *common;
@@ -318,72 +310,37 @@ struct stm32_adc {
u8 *rx_buf;
dma_addr_t rx_dma_buf;
unsigned int rx_buf_sz;
+ u32 difsel;
u32 pcsel;
u32 smpr_val[2];
struct stm32_adc_calib cal;
+ char chan_name[STM32_ADC_CH_MAX][STM32_ADC_CH_SZ];
};
-/**
- * struct stm32_adc_chan_spec - specification of stm32 adc channel
- * @type: IIO channel type
- * @channel: channel number (single ended)
- * @name: channel name (single ended)
- */
-struct stm32_adc_chan_spec {
- enum iio_chan_type type;
- int channel;
- const char *name;
+struct stm32_adc_diff_channel {
+ u32 vinp;
+ u32 vinn;
};
/**
* struct stm32_adc_info - stm32 ADC, per instance config data
- * @channels: Reference to stm32 channels spec
* @max_channels: Number of channels
* @resolutions: available resolutions
* @num_res: number of available resolutions
*/
struct stm32_adc_info {
- const struct stm32_adc_chan_spec *channels;
int max_channels;
const unsigned int *resolutions;
const unsigned int num_res;
};
-/*
- * Input definitions common for all instances:
- * stm32f4 can have up to 16 channels
- * stm32h7 can have up to 20 channels
- */
-static const struct stm32_adc_chan_spec stm32_adc_channels[] = {
- { IIO_VOLTAGE, 0, "in0" },
- { IIO_VOLTAGE, 1, "in1" },
- { IIO_VOLTAGE, 2, "in2" },
- { IIO_VOLTAGE, 3, "in3" },
- { IIO_VOLTAGE, 4, "in4" },
- { IIO_VOLTAGE, 5, "in5" },
- { IIO_VOLTAGE, 6, "in6" },
- { IIO_VOLTAGE, 7, "in7" },
- { IIO_VOLTAGE, 8, "in8" },
- { IIO_VOLTAGE, 9, "in9" },
- { IIO_VOLTAGE, 10, "in10" },
- { IIO_VOLTAGE, 11, "in11" },
- { IIO_VOLTAGE, 12, "in12" },
- { IIO_VOLTAGE, 13, "in13" },
- { IIO_VOLTAGE, 14, "in14" },
- { IIO_VOLTAGE, 15, "in15" },
- { IIO_VOLTAGE, 16, "in16" },
- { IIO_VOLTAGE, 17, "in17" },
- { IIO_VOLTAGE, 18, "in18" },
- { IIO_VOLTAGE, 19, "in19" },
-};
-
static const unsigned int stm32f4_adc_resolutions[] = {
/* sorted values so the index matches RES[1:0] in STM32F4_ADC_CR1 */
12, 10, 8, 6,
};
+/* stm32f4 can have up to 16 channels */
static const struct stm32_adc_info stm32f4_adc_info = {
- .channels = stm32_adc_channels,
.max_channels = 16,
.resolutions = stm32f4_adc_resolutions,
.num_res = ARRAY_SIZE(stm32f4_adc_resolutions),
@@ -394,9 +351,9 @@ static const unsigned int stm32h7_adc_resolutions[] = {
16, 14, 12, 10, 8,
};
+/* stm32h7 can have up to 20 channels */
static const struct stm32_adc_info stm32h7_adc_info = {
- .channels = stm32_adc_channels,
- .max_channels = 20,
+ .max_channels = STM32_ADC_CH_MAX,
.resolutions = stm32h7_adc_resolutions,
.num_res = ARRAY_SIZE(stm32h7_adc_resolutions),
};
@@ -983,15 +940,19 @@ pwr_dwn:
* stm32h7_adc_prepare() - Leave power down mode to enable ADC.
* @adc: stm32 adc instance
* Leave power down mode.
+ * Configure channels as single ended or differential before enabling ADC.
* Enable ADC.
* Restore calibration data.
- * Pre-select channels that may be used in PCSEL (required by input MUX / IO).
+ * Pre-select channels that may be used in PCSEL (required by input MUX / IO):
+ * - Only one input is selected for single ended (e.g. 'vinp')
+ * - Two inputs are selected for differential channels (e.g. 'vinp' & 'vinn')
*/
static int stm32h7_adc_prepare(struct stm32_adc *adc)
{
int ret;
stm32h7_adc_exit_pwr_down(adc);
+ stm32_adc_writel(adc, STM32H7_ADC_DIFSEL, adc->difsel);
ret = stm32h7_adc_enable(adc);
if (ret)
@@ -1263,10 +1224,23 @@ static int stm32_adc_read_raw(struct iio_dev *indio_dev,
return ret;
case IIO_CHAN_INFO_SCALE:
- *val = adc->common->vref_mv;
- *val2 = chan->scan_type.realbits;
+ if (chan->differential) {
+ *val = adc->common->vref_mv * 2;
+ *val2 = chan->scan_type.realbits;
+ } else {
+ *val = adc->common->vref_mv;
+ *val2 = chan->scan_type.realbits;
+ }
return IIO_VAL_FRACTIONAL_LOG2;
+ case IIO_CHAN_INFO_OFFSET:
+ if (chan->differential)
+ /* ADC_full_scale / 2 */
+ *val = -((1 << chan->scan_type.realbits) / 2);
+ else
+ *val = 0;
+ return IIO_VAL_INT;
+
default:
return -EINVAL;
}
@@ -1315,6 +1289,7 @@ static int stm32_adc_set_watermark(struct iio_dev *indio_dev, unsigned int val)
{
struct stm32_adc *adc = iio_priv(indio_dev);
unsigned int watermark = STM32_DMA_BUFFER_SIZE / 2;
+ unsigned int rx_buf_sz = STM32_DMA_BUFFER_SIZE;
/*
* dma cyclic transfers are used, buffer is split into two periods.
@@ -1323,7 +1298,7 @@ static int stm32_adc_set_watermark(struct iio_dev *indio_dev, unsigned int val)
* - one buffer (period) driver can push with iio_trigger_poll().
*/
watermark = min(watermark, val * (unsigned)(sizeof(u16)));
- adc->rx_buf_sz = watermark * 2;
+ adc->rx_buf_sz = min(rx_buf_sz, watermark * 2 * adc->num_conv);
return 0;
}
@@ -1628,29 +1603,40 @@ static void stm32_adc_smpr_init(struct stm32_adc *adc, int channel, u32 smp_ns)
}
static void stm32_adc_chan_init_one(struct iio_dev *indio_dev,
- struct iio_chan_spec *chan,
- const struct stm32_adc_chan_spec *channel,
- int scan_index, u32 smp)
+ struct iio_chan_spec *chan, u32 vinp,
+ u32 vinn, int scan_index, bool differential)
{
struct stm32_adc *adc = iio_priv(indio_dev);
-
- chan->type = channel->type;
- chan->channel = channel->channel;
- chan->datasheet_name = channel->name;
+ char *name = adc->chan_name[vinp];
+
+ chan->type = IIO_VOLTAGE;
+ chan->channel = vinp;
+ if (differential) {
+ chan->differential = 1;
+ chan->channel2 = vinn;
+ snprintf(name, STM32_ADC_CH_SZ, "in%d-in%d", vinp, vinn);
+ } else {
+ snprintf(name, STM32_ADC_CH_SZ, "in%d", vinp);
+ }
+ chan->datasheet_name = name;
chan->scan_index = scan_index;
chan->indexed = 1;
chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
- chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE);
+ chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_OFFSET);
chan->scan_type.sign = 'u';
chan->scan_type.realbits = adc->cfg->adc_info->resolutions[adc->res];
chan->scan_type.storagebits = 16;
chan->ext_info = stm32_adc_ext_info;
- /* Prepare sampling time settings */
- stm32_adc_smpr_init(adc, chan->channel, smp);
-
/* pre-build selected channels mask */
adc->pcsel |= BIT(chan->channel);
+ if (differential) {
+ /* pre-build diff channels mask */
+ adc->difsel |= BIT(chan->channel);
+ /* Also add negative input to pre-selected channels */
+ adc->pcsel |= BIT(chan->channel2);
+ }
}
static int stm32_adc_chan_of_init(struct iio_dev *indio_dev)
@@ -1658,17 +1644,40 @@ static int stm32_adc_chan_of_init(struct iio_dev *indio_dev)
struct device_node *node = indio_dev->dev.of_node;
struct stm32_adc *adc = iio_priv(indio_dev);
const struct stm32_adc_info *adc_info = adc->cfg->adc_info;
+ struct stm32_adc_diff_channel diff[STM32_ADC_CH_MAX];
struct property *prop;
const __be32 *cur;
struct iio_chan_spec *channels;
- int scan_index = 0, num_channels, ret;
+ int scan_index = 0, num_channels = 0, num_diff = 0, ret, i;
u32 val, smp = 0;
- num_channels = of_property_count_u32_elems(node, "st,adc-channels");
- if (num_channels < 0 ||
- num_channels > adc_info->max_channels) {
+ ret = of_property_count_u32_elems(node, "st,adc-channels");
+ if (ret > adc_info->max_channels) {
dev_err(&indio_dev->dev, "Bad st,adc-channels?\n");
- return num_channels < 0 ? num_channels : -EINVAL;
+ return -EINVAL;
+ } else if (ret > 0) {
+ num_channels += ret;
+ }
+
+ ret = of_property_count_elems_of_size(node, "st,adc-diff-channels",
+ sizeof(*diff));
+ if (ret > adc_info->max_channels) {
+ dev_err(&indio_dev->dev, "Bad st,adc-diff-channels?\n");
+ return -EINVAL;
+ } else if (ret > 0) {
+ int size = ret * sizeof(*diff) / sizeof(u32);
+
+ num_diff = ret;
+ num_channels += ret;
+ ret = of_property_read_u32_array(node, "st,adc-diff-channels",
+ (u32 *)diff, size);
+ if (ret)
+ return ret;
+ }
+
+ if (!num_channels) {
+ dev_err(&indio_dev->dev, "No channels configured\n");
+ return -ENODATA;
}
/* Optional sample time is provided either for each, or all channels */
@@ -1689,6 +1698,33 @@ static int stm32_adc_chan_of_init(struct iio_dev *indio_dev)
return -EINVAL;
}
+ /* Channel can't be configured both as single-ended & diff */
+ for (i = 0; i < num_diff; i++) {
+ if (val == diff[i].vinp) {
+ dev_err(&indio_dev->dev,
+ "channel %d miss-configured\n", val);
+ return -EINVAL;
+ }
+ }
+ stm32_adc_chan_init_one(indio_dev, &channels[scan_index], val,
+ 0, scan_index, false);
+ scan_index++;
+ }
+
+ for (i = 0; i < num_diff; i++) {
+ if (diff[i].vinp >= adc_info->max_channels ||
+ diff[i].vinn >= adc_info->max_channels) {
+ dev_err(&indio_dev->dev, "Invalid channel in%d-in%d\n",
+ diff[i].vinp, diff[i].vinn);
+ return -EINVAL;
+ }
+ stm32_adc_chan_init_one(indio_dev, &channels[scan_index],
+ diff[i].vinp, diff[i].vinn, scan_index,
+ true);
+ scan_index++;
+ }
+
+ for (i = 0; i < scan_index; i++) {
/*
* Using of_property_read_u32_index(), smp value will only be
* modified if valid u32 value can be decoded. This allows to
@@ -1696,12 +1732,9 @@ static int stm32_adc_chan_of_init(struct iio_dev *indio_dev)
* value per channel.
*/
of_property_read_u32_index(node, "st,min-sample-time-nsecs",
- scan_index, &smp);
-
- stm32_adc_chan_init_one(indio_dev, &channels[scan_index],
- &adc_info->channels[val],
- scan_index, smp);
- scan_index++;
+ i, &smp);
+ /* Prepare sampling time settings */
+ stm32_adc_smpr_init(adc, channels[i].channel, smp);
}
indio_dev->num_channels = scan_index;
diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index b3e573cc6f5f..80df5a377d30 100644
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -523,7 +523,7 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
}
am335x_tsc_se_adc_done(adc_dev->mfd_tscadc);
- if (found == false)
+ if (!found)
ret = -EBUSY;
err_unlock: