[PATCH v5 4/8] hwmon: (amc6821) add support for tsd,mule

Farouk Bouabid
2024-07-08T16:13:23Z

Theobroma Systems Mule is an MCU that emulates a set of I2C devices,
among which is an amc6821 and other devices that are reachable through
an I2C-mux.

The devices on the mux can be selected by writing the appropriate device
number to an I2C config register (amc6821: reg 0xff)

Implement "tsd,mule" compatible to instantiate the I2C-mux platform device
when probing the amc6821.

Signed-off-by: Farouk Bouabid <farouk.bouabid@cherry.de>
---
drivers/hwmon/amc6821.c | 25 ++++++++++++++++++++++++-
1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/drivers/hwmon/amc6821.c b/drivers/hwmon/amc6821.c
index 0661cc6a6f8e..93c3b79b5f13 100644
--- a/drivers/hwmon/amc6821.c
+++ b/drivers/hwmon/amc6821.c
@@ -22,6 +22,7 @@
#include <linux/minmax.h>
#include <linux/module.h>
#include <linux/mutex.h>
+#include <linux/of_platform.h>
#include <linux/regmap.h>
#include <linux/slab.h>

@@ -895,8 +896,17 @@ static const struct regmap_config amc6821_regmap_config = {
.cache_type = REGCACHE_MAPLE,
};

+static const struct regmap_config amc6821_mule_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .max_register = 0xff,
+ .volatile_reg = amc6821_volatile_reg,
+ .cache_type = REGCACHE_MAPLE,
+};
+
static int amc6821_probe(struct i2c_client *client)
{
+ const struct regmap_config *config;
struct device *dev = &client->dev;
struct amc6821_data *data;
struct device *hwmon_dev;
@@ -907,7 +917,10 @@ static int amc6821_probe(struct i2c_client *client)
if (!data)
return -ENOMEM;

- regmap = devm_regmap_init_i2c(client, &amc6821_regmap_config);
+ config = of_device_is_compatible(dev->of_node, "tsd,mule") ?
+ &amc6821_mule_regmap_config : &amc6821_regmap_config;
+
+ regmap = devm_regmap_init_i2c(client, config);
if (IS_ERR(regmap))
return dev_err_probe(dev, PTR_ERR(regmap),
"Failed to initialize regmap\n");
@@ -917,6 +930,13 @@ static int amc6821_probe(struct i2c_client *client)
if (err)
return err;

+ if (of_device_is_compatible(dev->of_node, "tsd,mule")) {
+ err = devm_of_platform_populate(dev);
+ if (err)
+ return dev_err_probe(dev, err,
+ "Failed to create sub-devices\n");
+ }
+
hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
data, &amc6821_chip_info,
amc6821_groups);
@@ -934,6 +954,9 @@ static const struct of_device_id __maybe_unused amc6821_of_match[] = {
{
.compatible = "ti,amc6821",
},
+ {
+ .compatible = "tsd,mule",
+ },
{ }
};

--
2.34.1