[PATCH v2 2/4] iio: adc: at91_adc: const-ify some driver data

From: Alexandru Ardelean
Date: Wed Sep 30 2020 - 01:56:19 EST


The main intent is to get rid of the cast for the void-pointer returned by
of_device_get_match_data().

This requires const-ifying the 'caps' and 'registers' references on the
at91_adc_state struct.

The caps can be obtained also from the old platform_data (in the
at91_adc_probe_pdata() function), but that cast is not touched in this
patch, since the old platform_data should be removed/cleaned-away.
Also, that cast deals with converting a kernel_ulong_t type to a pointer.
So, updating that cast doesn't yield any benefit.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
---
drivers/iio/adc/at91_adc.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
index c9ec0a4a357e..7d846a2852a5 100644
--- a/drivers/iio/adc/at91_adc.c
+++ b/drivers/iio/adc/at91_adc.c
@@ -202,7 +202,7 @@ struct at91_adc_state {
struct mutex lock;
u8 num_channels;
void __iomem *reg_base;
- struct at91_adc_reg_desc *registers;
+ const struct at91_adc_reg_desc *registers;
u32 startup_time;
u8 sample_hold_time;
bool sleep_mode;
@@ -214,7 +214,7 @@ struct at91_adc_state {
u32 res; /* resolution used for convertions */
bool low_res; /* the resolution corresponds to the lowest one */
wait_queue_head_t wq_data_avail;
- struct at91_adc_caps *caps;
+ const struct at91_adc_caps *caps;

/*
* Following ADC channels are shared by touchscreen:
@@ -550,7 +550,7 @@ static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
{
struct iio_dev *idev = iio_trigger_get_drvdata(trig);
struct at91_adc_state *st = iio_priv(idev);
- struct at91_adc_reg_desc *reg = st->registers;
+ const struct at91_adc_reg_desc *reg = st->registers;
u32 status = at91_adc_readl(st, reg->trigger_register);
int value;
u8 bit;
@@ -876,7 +876,7 @@ static int at91_adc_probe_dt(struct iio_dev *idev,
if (!node)
return -EINVAL;

- st->caps = (struct at91_adc_caps *)of_device_get_match_data(&pdev->dev);
+ st->caps = of_device_get_match_data(&pdev->dev);

st->use_external = of_property_read_bool(node, "atmel,adc-use-external-triggers");

--
2.17.1