On Sun, 7 May 2023 at 20:47, Marek Vasut <marex@xxxxxxx> wrote:
>
> Add support for MLX90615 Infra Red Thermometer, which seems to be
> the predecesor of MLX90614 . There are significant differences in
> the register layout compared to MLX90614, but the functionality
> of the device is virtually identical.
>
> The following differences have been identified:
> - RAM/EEPROM/SLEEP access opcodes are different
> - RAM/EEPROM registers are at different offsets
> - EEPROM emissivity and configuration registers are at different offsets
> - EEPROM configuration register bits are shuffled around
> - EEPROM emissivity settings are 14 bit on MLX90615 , 16 bit on MLX90614
> - MLX90615 can only ever support one sensor, MLX90614 could support two
> - FIR filter is set to fixed settings on MLX90615
> - IIR filter coefficients are different
>
> This patch fills in the MLX90615 specific description and quirk handling.
>
> Signed-off-by: Marek Vasut <marex@xxxxxxx>
> ---
> NOTE: The IIR coefficients need to be checked
> ---
> Cc: Crt Mori <cmo@xxxxxxxxxxx>
> Cc: Jonathan Cameron <jic23@xxxxxxxxxx>
> Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@xxxxxxxxxx>
> Cc: Lars-Peter Clausen <lars@xxxxxxxxxx>
> Cc: Marek Vasut <marex@xxxxxxx>
> Cc: Peter Meerwald <pmeerw@xxxxxxxxxx>
> Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> Cc: devicetree@xxxxxxxxxxxxxxx
> Cc: linux-iio@xxxxxxxxxxxxxxx
> ---
> V2: Split the patch up into cleanups, abstraction and MLX90615 addition
> ---
> drivers/iio/temperature/mlx90614.c | 49 +++++++++++++++++++++++++++---
> 1 file changed, 45 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/iio/temperature/mlx90614.c b/drivers/iio/temperature/mlx90614.c
> index d6d2a5afaf8c0..5bcd323921db5 100644
> --- a/drivers/iio/temperature/mlx90614.c
> +++ b/drivers/iio/temperature/mlx90614.c
> @@ -1,12 +1,15 @@
> // SPDX-License-Identifier: GPL-2.0-only
> /*
> - * mlx90614.c - Support for Melexis MLX90614 contactless IR temperature sensor
> + * mlx90614.c - Support for Melexis MLX90614/MLX90615 contactless IR temperature sensor
> *
> * Copyright (c) 2014 Peter Meerwald <pmeerw@xxxxxxxxxx>
> * Copyright (c) 2015 Essensium NV
> * Copyright (c) 2015 Melexis
> *
> - * Driver for the Melexis MLX90614 I2C 16-bit IR thermopile sensor
> + * Driver for the Melexis MLX90614/MLX90615 I2C 16-bit IR thermopile sensor
> + *
> + * MLX90614 - 17-bit ADC + MLX90302 DSP
> + * MLX90615 - 16-bit ADC + MLX90325 DSP
> *
> * (7-bit I2C slave address 0x5a, 100KHz bus speed only!)
> *
> @@ -35,6 +38,10 @@
> #define MLX90614_OP_EEPROM 0x20
> #define MLX90614_OP_SLEEP 0xff
>
> +#define MLX90615_OP_EEPROM 0x10
> +#define MLX90615_OP_RAM 0x20
> +#define MLX90615_OP_SLEEP 0xc6
> +
> /* Control bits in configuration register */
> #define MLX90614_CONFIG_IIR_SHIFT 0 /* IIR coefficient */
> #define MLX90614_CONFIG_IIR_MASK (0x7 << MLX90614_CONFIG_IIR_SHIFT)
> @@ -43,11 +50,16 @@
> #define MLX90614_CONFIG_FIR_SHIFT 8 /* FIR coefficient */
> #define MLX90614_CONFIG_FIR_MASK (0x7 << MLX90614_CONFIG_FIR_SHIFT)
>
> +#define MLX90615_CONFIG_IIR_SHIFT 12 /* IIR coefficient */
> +#define MLX90615_CONFIG_IIR_MASK (0x7 << MLX90615_CONFIG_IIR_SHIFT)
> +
> /* Timings (in ms) */
> #define MLX90614_TIMING_EEPROM 20 /* time for EEPROM write/erase to complete */
> #define MLX90614_TIMING_WAKEUP 34 /* time to hold SDA low for wake-up */
> #define MLX90614_TIMING_STARTUP 250 /* time before first data after wake-up */
>
> +#define MLX90615_TIMING_WAKEUP 22 /* time to hold SCL low for wake-up */
> +
> #define MLX90614_AUTOSLEEP_DELAY 5000 /* default autosleep delay */
>
> /* Magic constants */
> @@ -306,8 +318,8 @@ static int mlx90614_read_raw(struct iio_dev *indio_dev,
> *val2 = ret * chip_info->emissivity_res;
> }
> return IIO_VAL_INT_PLUS_NANO;
> - case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: /* IIR setting with
> - FIR = 1024 */
> + /* IIR setting with FIR=1024 (MLX90614) or FIR=65536 (MLX90615) */
> + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
> ret = mlx90614_power_get(data, false);
> if (ret < 0)
> return ret;
> @@ -666,14 +678,43 @@ static const struct mlx_chip_info mlx90614_chip_info = {
> },
> };
>
> +static const struct mlx_chip_info mlx90615_chip_info = {
> + .op_eeprom_emissivity = MLX90615_OP_EEPROM | 0x03,
> + .op_eeprom_config1 = MLX90615_OP_EEPROM | 0x02,
> + .op_ram_ta = MLX90615_OP_RAM | 0x06,
> + .op_ram_tobj1 = MLX90615_OP_RAM | 0x07,
> + .op_ram_tobj2 = MLX90615_OP_RAM | 0x08,
> + .op_sleep = MLX90615_OP_SLEEP,
> + .dual_channel = false,
> + .wakeup_delay_ms = MLX90615_TIMING_WAKEUP,
> + .emissivity_max = 16383,
> + .emissivity_res = 1000000000 / 16383,
This makes me wonder if we could just drop the emissivity_res and have
it calculate it using emissivity_max, since both chips will do it.
> + .fir_config_mask = 0, /* MLX90615 FIR is fixed */
> + .iir_config_mask = MLX90615_CONFIG_IIR_MASK,
> + /* IIR value 0 is FORBIDDEN COMBINATION on MLX90615 */
> + .iir_valid_offset = 1,
> + .iir_values = { 723, 77, 42, 31, 28, 20, 18 },
> + .iir_freqs = {
> + { 0, 180000 }, /* 14% ~= 0.18 Hz */
> + { 0, 200000 }, /* 17% ~= 0.20 Hz */
> + { 0, 280000 }, /* 20% ~= 0.28 Hz */
> + { 0, 310000 }, /* 25% ~= 0.31 Hz */
> + { 0, 420000 }, /* 33% ~= 0.42 Hz */
> + { 0, 770000 }, /* 50% ~= 0.77 Hz */
> + { 7, 230000 }, /* 100% ~= 7.23 Hz */
> + },
> +};
> +
> static const struct i2c_device_id mlx90614_id[] = {
> { "mlx90614", .driver_data = (kernel_ulong_t)&mlx90614_chip_info },
> + { "mlx90615", .driver_data = (kernel_ulong_t)&mlx90615_chip_info },
> { }
> };
> MODULE_DEVICE_TABLE(i2c, mlx90614_id);
>
> static const struct of_device_id mlx90614_of_match[] = {
> { .compatible = "melexis,mlx90614", .data = &mlx90614_chip_info },
> + { .compatible = "melexis,mlx90615", .data = &mlx90615_chip_info },
> { }
> };
> MODULE_DEVICE_TABLE(of, mlx90614_of_match);
> --
> 2.39.2
>
