[PATCH v2 6/8] reset: imx8mp-audiomix: Extend the driver usage

Laurentiu Mihalcea
2025-10-17T11:21:58Z

From: Laurentiu Mihalcea <laurentiu.mihalcea@nxp.com>

Some NXP SoCs integrate one or more, per-subsystem, block control IPs,
which allow users to control the assertion and de-assertion of the
reset lines tied to some peripherals present in said subsystems. Some
examples of such SoCs include i.MX8MP with AUDIOMIX block control and
i.MX8ULP with SIM LPAV.

Some of the aformentioned block control IPs exhibit a common pattern with
respect to the assertion and de-assertion of the reset lines. Namely, the
user is able to control the state of the reset line by toggling a bit from
one of the IP's registers.

Linux can take advantage of this pattern and, instead of having one driver
for each block control IP, a single, more generic driver could be used.

To allow this to happen, the previous approach, in which a single reset
map is used, is replaced by a per-driver approach, in which each auxiliary
device driver holds a reference to a certain reset map.

Reviewed-by: Daniel Baluta <daniel.baluta@nxp.com>
Signed-off-by: Laurentiu Mihalcea <laurentiu.mihalcea@nxp.com>
---
drivers/reset/reset-imx8mp-audiomix.c | 18 ++++++++++++++++--
1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/drivers/reset/reset-imx8mp-audiomix.c b/drivers/reset/reset-imx8mp-audiomix.c
index c74ce6e04177..c370913107f5 100644
--- a/drivers/reset/reset-imx8mp-audiomix.c
+++ b/drivers/reset/reset-imx8mp-audiomix.c
@@ -24,7 +24,12 @@ struct imx8mp_reset_map {
bool active_low;
};

-static const struct imx8mp_reset_map reset_map[] = {
+struct imx8mp_reset_info {
+ const struct imx8mp_reset_map *map;
+ int num_lines;
+};
+
+static const struct imx8mp_reset_map imx8mp_reset_map[] = {
[IMX8MP_AUDIOMIX_EARC_RESET] = {
.offset = IMX8MP_AUDIOMIX_EARC_RESET_OFFSET,
.mask = BIT(0),
@@ -45,10 +50,16 @@ static const struct imx8mp_reset_map reset_map[] = {
},
};

+static const struct imx8mp_reset_info imx8mp_reset_info = {
+ .map = imx8mp_reset_map,
+ .num_lines = ARRAY_SIZE(imx8mp_reset_map),
+};
+
struct imx8mp_audiomix_reset {
struct reset_controller_dev rcdev;
void __iomem *base;
struct regmap *regmap;
+ const struct imx8mp_reset_info *rinfo;
};

static struct imx8mp_audiomix_reset *to_imx8mp_audiomix_reset(struct reset_controller_dev *rcdev)
@@ -60,6 +71,7 @@ static int imx8mp_audiomix_update(struct reset_controller_dev *rcdev,
unsigned long id, bool assert)
{
struct imx8mp_audiomix_reset *priv = to_imx8mp_audiomix_reset(rcdev);
+ const struct imx8mp_reset_map *reset_map = priv->rinfo->map;
unsigned int mask, offset, active_low, shift, val;

mask = reset_map[id].mask;
@@ -144,7 +156,8 @@ static int imx8mp_audiomix_reset_probe(struct auxiliary_device *adev,
return -ENOMEM;

priv->rcdev.owner = THIS_MODULE;
- priv->rcdev.nr_resets = ARRAY_SIZE(reset_map);
+ priv->rinfo = (const struct imx8mp_reset_info *)id->driver_data;
+ priv->rcdev.nr_resets = priv->rinfo->num_lines;
priv->rcdev.ops = &imx8mp_audiomix_reset_ops;
priv->rcdev.of_node = dev->parent->of_node;
priv->rcdev.dev = dev;
@@ -168,6 +181,7 @@ static int imx8mp_audiomix_reset_probe(struct auxiliary_device *adev,
static const struct auxiliary_device_id imx8mp_audiomix_reset_ids[] = {
{
.name = "clk_imx8mp_audiomix.reset",
+ .driver_data = (kernel_ulong_t)&imx8mp_reset_info,
},
{ }
};
--
2.43.0