[PATCH] iio: at91-sama5d2_adc: remove usage of iio_priv_to_dev() helper
From: Alexandru Ardelean
Date: Mon May 25 2020 - 06:53:50 EST
We may want to get rid of the iio_priv_to_dev() helper. The reason is that
we will hide some of the members of the iio_dev structure (to prevent
drivers from accessing them directly), and that will also mean hiding the
implementation of the iio_priv_to_dev() helper inside the IIO core.
Hiding the implementation of iio_priv_to_dev() implies that some fast-paths
may not be fast anymore, so a general idea is to try to get rid of the
iio_priv_to_dev() altogether.
The iio_priv() helper won't be affected by the rework, as the iio_dev
struct will keep a reference to the private information.
For this driver, not using iio_priv_to_dev(), means reworking some paths to
pass the iio device and using iio_priv() to access the private information,
and also keeping a reference to the iio device for some quirky paths.
One [quirky] path is the at91_adc_workq_handler() which requires the IIO
device & the state struct to push to buffers.
Since this requires the back-ref to the IIO device, the
at91_adc_touch_pos() also uses it. This simplifies the patch a bit. The
information required in this function is mostly for debugging purposes.
Replacing it with a reference to the IIO device would have been a slightly
bigger change, which may not be worth it (for just the debugging purpose
and given that we need the back-ref to the IIO device anyway).
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
---
drivers/iio/adc/at91-sama5d2_adc.c | 30 +++++++++++++++++-------------
1 file changed, 17 insertions(+), 13 deletions(-)
diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
index 9abbbdcc7420..7bce18444430 100644
--- a/drivers/iio/adc/at91-sama5d2_adc.c
+++ b/drivers/iio/adc/at91-sama5d2_adc.c
@@ -402,6 +402,7 @@ struct at91_adc_state {
wait_queue_head_t wq_data_available;
struct at91_adc_dma dma_st;
struct at91_adc_touch touch_st;
+ struct iio_dev *indio_dev;
u16 buffer[AT91_BUFFER_MAX_HWORDS];
/*
* lock to prevent concurrent 'single conversion' requests through
@@ -642,13 +643,13 @@ static u16 at91_adc_touch_pos(struct at91_adc_state *st, int reg)
/* first half of register is the x or y, second half is the scale */
val = at91_adc_readl(st, reg);
if (!val)
- dev_dbg(&iio_priv_to_dev(st)->dev, "pos is 0\n");
+ dev_dbg(&st->indio_dev->dev, "pos is 0\n");
pos = val & AT91_SAMA5D2_XYZ_MASK;
result = (pos << AT91_SAMA5D2_MAX_POS_BITS) - pos;
scale = (val >> 16) & AT91_SAMA5D2_XYZ_MASK;
if (scale == 0) {
- dev_err(&iio_priv_to_dev(st)->dev, "scale is 0\n");
+ dev_err(&st->indio_dev->dev, "scale is 0\n");
return 0;
}
result /= scale;
@@ -1204,9 +1205,9 @@ static unsigned at91_adc_startup_time(unsigned startup_time_min,
return i;
}
-static void at91_adc_setup_samp_freq(struct at91_adc_state *st, unsigned freq)
+static void at91_adc_setup_samp_freq(struct iio_dev *indio_dev, unsigned freq)
{
- struct iio_dev *indio_dev = iio_priv_to_dev(st);
+ struct at91_adc_state *st = iio_priv(indio_dev);
unsigned f_per, prescal, startup, mr;
f_per = clk_get_rate(st->per_clk);
@@ -1275,9 +1276,9 @@ static void at91_adc_pen_detect_interrupt(struct at91_adc_state *st)
st->touch_st.touching = true;
}
-static void at91_adc_no_pen_detect_interrupt(struct at91_adc_state *st)
+static void at91_adc_no_pen_detect_interrupt(struct iio_dev *indio_dev)
{
- struct iio_dev *indio_dev = iio_priv_to_dev(st);
+ struct at91_adc_state *st = iio_priv(indio_dev);
at91_adc_writel(st, AT91_SAMA5D2_TRGR,
AT91_SAMA5D2_TRGR_TRGMOD_NO_TRIGGER);
@@ -1297,7 +1298,7 @@ static void at91_adc_workq_handler(struct work_struct *workq)
struct at91_adc_touch, workq);
struct at91_adc_state *st = container_of(touch_st,
struct at91_adc_state, touch_st);
- struct iio_dev *indio_dev = iio_priv_to_dev(st);
+ struct iio_dev *indio_dev = st->indio_dev;
iio_push_to_buffers(indio_dev, st->buffer);
}
@@ -1318,7 +1319,7 @@ static irqreturn_t at91_adc_interrupt(int irq, void *private)
at91_adc_pen_detect_interrupt(st);
} else if ((status & AT91_SAMA5D2_IER_NOPEN)) {
/* nopen detected IRQ */
- at91_adc_no_pen_detect_interrupt(st);
+ at91_adc_no_pen_detect_interrupt(indio);
} else if ((status & AT91_SAMA5D2_ISR_PENS) &&
((status & rdy_mask) == rdy_mask)) {
/* periodic trigger IRQ - during pen sense */
@@ -1486,7 +1487,7 @@ static int at91_adc_write_raw(struct iio_dev *indio_dev,
val > st->soc_info.max_sample_rate)
return -EINVAL;
- at91_adc_setup_samp_freq(st, val);
+ at91_adc_setup_samp_freq(indio_dev, val);
return 0;
default:
return -EINVAL;
@@ -1624,8 +1625,10 @@ static int at91_adc_update_scan_mode(struct iio_dev *indio_dev,
return 0;
}
-static void at91_adc_hw_init(struct at91_adc_state *st)
+static void at91_adc_hw_init(struct iio_dev *indio_dev)
{
+ struct at91_adc_state *st = iio_priv(indio_dev);
+
at91_adc_writel(st, AT91_SAMA5D2_CR, AT91_SAMA5D2_CR_SWRST);
at91_adc_writel(st, AT91_SAMA5D2_IDR, 0xffffffff);
/*
@@ -1635,7 +1638,7 @@ static void at91_adc_hw_init(struct at91_adc_state *st)
at91_adc_writel(st, AT91_SAMA5D2_MR,
AT91_SAMA5D2_MR_TRANSFER(2) | AT91_SAMA5D2_MR_ANACH);
- at91_adc_setup_samp_freq(st, st->soc_info.min_sample_rate);
+ at91_adc_setup_samp_freq(indio_dev, st->soc_info.min_sample_rate);
/* configure extended mode register */
at91_adc_config_emr(st);
@@ -1718,6 +1721,7 @@ static int at91_adc_probe(struct platform_device *pdev)
indio_dev->num_channels = ARRAY_SIZE(at91_adc_channels);
st = iio_priv(indio_dev);
+ st->indio_dev = indio_dev;
bitmap_set(&st->touch_st.channels_bitmask,
AT91_SAMA5D2_TOUCH_X_CHAN_IDX, 1);
@@ -1829,7 +1833,7 @@ static int at91_adc_probe(struct platform_device *pdev)
goto vref_disable;
}
- at91_adc_hw_init(st);
+ at91_adc_hw_init(indio_dev);
ret = clk_prepare_enable(st->per_clk);
if (ret)
@@ -1945,7 +1949,7 @@ static __maybe_unused int at91_adc_resume(struct device *dev)
if (ret)
goto vref_disable_resume;
- at91_adc_hw_init(st);
+ at91_adc_hw_init(indio_dev);
/* reconfiguring trigger hardware state */
if (!iio_buffer_enabled(indio_dev))
--
2.25.1