Re: [PATCH v2 1/5] hwmon: (max31790) Rework to use regmap

[Guenter Roeck <linux@roeck-us.net>]

On 4/12/21 7:59 PM, Václav Kubernát wrote:
> Converting the driver to use regmap makes it more generic. It also makes
> it a lot easier to debug through debugfs.
> 
> Signed-off-by: Václav Kubernát <kubernat@cesnet.cz>
> ---
>  drivers/hwmon/Kconfig    |   1 +
>  drivers/hwmon/max31790.c | 254 ++++++++++++++++++++-------------------
>  2 files changed, 133 insertions(+), 122 deletions(-)
> 
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index 1ecf697d8d99..9f11d036c316 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -1095,6 +1095,7 @@ config SENSORS_MAX6697
>  config SENSORS_MAX31790
>  	tristate "Maxim MAX31790 sensor chip"
>  	depends on I2C
> +	select REGMAP_I2C
>  	help
>  	  If you say yes here you get support for 6-Channel PWM-Output
>  	  Fan RPM Controller.
> diff --git a/drivers/hwmon/max31790.c b/drivers/hwmon/max31790.c
> index 2c6b333a28e9..e3765ce4444a 100644
> --- a/drivers/hwmon/max31790.c
> +++ b/drivers/hwmon/max31790.c
> @@ -12,6 +12,7 @@
>  #include <linux/init.h>
>  #include <linux/jiffies.h>
>  #include <linux/module.h>
> +#include <linux/regmap.h>
>  #include <linux/slab.h>
>  
>  /* MAX31790 registers */
> @@ -46,92 +47,53 @@
>  
>  #define NR_CHANNEL			6
>  
> +#define MAX31790_REG_USER_BYTE_67	0x67
> +
> +#define BULK_TO_U16(msb, lsb)		(((msb) << 8) + (lsb))
> +#define U16_MSB(num)			(((num) & 0xFF00) >> 8)
> +#define U16_LSB(num)			((num) & 0x00FF)
> +
> +static const struct regmap_range max31790_ro_range = {
> +	.range_min = MAX31790_REG_TACH_COUNT(0),
> +	.range_max = MAX31790_REG_PWMOUT(0) - 1,
> +};
> +
> +static const struct regmap_access_table max31790_wr_table = {
> +	.no_ranges = &max31790_ro_range,
> +	.n_no_ranges = 1,
> +};
> +
> +static const struct regmap_range max31790_volatile_ranges[] = {
> +	regmap_reg_range(MAX31790_REG_TACH_COUNT(0), MAX31790_REG_TACH_COUNT(12)),
> +	regmap_reg_range(MAX31790_REG_FAN_FAULT_STATUS2, MAX31790_REG_FAN_FAULT_STATUS1),
> +};
> +
> +static const struct regmap_access_table max31790_volatile_table = {
> +	.no_ranges = max31790_volatile_ranges,
> +	.n_no_ranges = 2,
> +	.n_yes_ranges = 0
> +};

Looks like my reply to this got lost. Other regmap code suggests that
volatile register ranges are identified with yes_ranges, not with no_ranges.
"no" seems to mean "not volatile". Please verify and confirm if the
above code does what you want it to do.

Thanks,
Guenter