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

Guenter Roeck
2024-07-08T21:45:43Z

On 7/8/24 09:12, Farouk Bouabid wrote:
> 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,

Unnecessary since the maximum possible register address is 0xff.

> + .volatile_reg = amc6821_volatile_reg,
> + .cache_type = REGCACHE_MAPLE,
> +};
> +

Anyway, don't bother. Just drop max_register from amc6821_regmap_config.

Thanks,
Guenter

> 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",
> + },
> { }
> };
>
>