From: Marius Cristea <marius.cristea@xxxxxxxxxxxxx> This is the iio driver for Microchip family of 153.6 ksps, Low-Noise 16/24-Bit Delta-Sigma ADCs with an SPI interface (Microchip's MCP3461, MCP3462, MCP3464, MCP3461R, MCP3462R, MCP3464R, MCP3561, MCP3562, MCP3564, MCP3561R, MCP3562R and MCP3564R analog to digital converters). Signed-off-by: Marius Cristea <marius.cristea@xxxxxxxxxxxxx> --- .../ABI/testing/sysfs-bus-iio-adc-mcp3564 | 53 + MAINTAINERS | 7 + drivers/iio/adc/Kconfig | 13 + drivers/iio/adc/Makefile | 1 + drivers/iio/adc/mcp3564.c | 1527 +++++++++++++++++ 5 files changed, 1601 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-adc-mcp3564 create mode 100644 drivers/iio/adc/mcp3564.c diff --git a/Documentation/ABI/testing/sysfs-bus-iio-adc-mcp3564 b/Documentation/ABI/testing/sysfs-bus-iio-adc-mcp3564 new file mode 100644 index 000000000000..4d6b1f40e277 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-iio-adc-mcp3564 @@ -0,0 +1,53 @@ +What: /sys/bus/iio/devices/iio:deviceX/boost_current_gain +KernelVersion: 6.4 +Contact: linux-iio@xxxxxxxxxxxxxxx +Description: + This attribute is used to set the gain of the biasing current + circuit of the Delta-Sigma modulator. The different BOOST + settings are applied to the entire modulator circuit, including + the voltage reference buffers. + +What: /sys/bus/iio/devices/iio:deviceX/boost_current_gain_available +KernelVersion: 6.4 +Contact: linux-iio@xxxxxxxxxxxxxxx +Description: + Reading returns a list with the possible gain values for + the current biasing circuit of the Delta-Sigma modulator. + +What: /sys/bus/iio/devices/iio:deviceX/auto_zeroing_mux_enable +KernelVersion: 6.4 +Contact: linux-iio@xxxxxxxxxxxxxxx +Description: + This attribute is used to enable the analog input multiplexer + auto-zeroing algorithm (the input multiplexer and the ADC + include an offset cancellation algorithm that cancels the offset + contribution of the ADC). When the offset cancellation algorithm + is enabled, ADC takes two conversions, one with the differential + input as VIN+/VIN-, one with VIN+/VIN- inverted. In this case the + conversion time is multiplied by two compared to the default + case where the algorithm is disabled. This technique allows the + cancellation of the ADC offset error and the achievement of + ultra-low offset without any digital calibration. The resulting + offset is the residue of the difference between the two + conversions, which is on the order of magnitude of the noise + floor. This offset is effectively canceled at every conversion, + so the residual offset error temperature drift is extremely low. + Write '1' to enable it, write '0' to disable it. + +What: /sys/bus/iio/devices/iio:deviceX/auto_zeroing_ref_enable +KernelVersion: 6.4 +Contact: linux-iio@xxxxxxxxxxxxxxx +Description: + This attribute is used to enable the chopping algorithm for the + internal voltage reference buffer. This setting has no effect + when external voltage reference is selected. + Internal voltage reference buffer injects a certain quantity of + 1/f noise into the system that can be modulated with the + incoming input signals and can limit the SNR performance at + higher Oversampling Ratio values (over 256). To overcome this + limitation, the buffer includes an auto-zeroing algorithm that + greatly reduces (cancels out) the 1/f noise and cancels the + offset value of the reference buffer. As a result, the SNR of + the system is not affected by this 1/f noise component of the + reference buffer, even at maximum oversampling ratio values. + Write '1' to enable it, write '0' to disable it. diff --git a/MAINTAINERS b/MAINTAINERS index 6969a2962ffe..50c879f85e1e 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -13798,6 +13798,13 @@ S: Supported F: Documentation/devicetree/bindings/regulator/mcp16502-regulator.txt F: drivers/regulator/mcp16502.c +MICROCHIP MCP3564 ADC DRIVER +M: Marius Cristea <marius.cristea@xxxxxxxxxxxxx> +L: linux-iio@xxxxxxxxxxxxxxx +S: Supported +F: Documentation/devicetree/bindings/iio/adc/microchip,mcp3564.yaml +F: drivers/iio/adc/mcp3564.c + MICROCHIP MCP3911 ADC DRIVER M: Marcus Folkesson <marcus.folkesson@xxxxxxxxx> M: Kent Gustavsson <kent@xxxxxxxxxx> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index 53098aca06ea..782bf5eec8ed 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -768,6 +768,19 @@ config MCP3422 This driver can also be built as a module. If so, the module will be called mcp3422. +config MCP3564 + tristate "Microchip Technology MCP3461/2/4/R, MCP3561/2/4/R driver" + depends on SPI + depends on IIO + help + Say yes here to build support for Microchip Technology's MCP3461, + MCP3462, MCP3464, MCP3461R, MCP3462R, MCP3464R, MCP3561, MCP3562, + MCP3564, MCP3561R, MCP3562R and MCP3564R analog to digital + converters. + + This driver can also be built as a module. If so, the module will be + called mcp3564. + config MCP3911 tristate "Microchip Technology MCP3911 driver" depends on SPI diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index e07e4a3e6237..91f713af574f 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -70,6 +70,7 @@ obj-$(CONFIG_MAX1363) += max1363.o obj-$(CONFIG_MAX9611) += max9611.o obj-$(CONFIG_MCP320X) += mcp320x.o obj-$(CONFIG_MCP3422) += mcp3422.o +obj-$(CONFIG_MCP3564) += mcp3564.o obj-$(CONFIG_MCP3911) += mcp3911.o obj-$(CONFIG_MEDIATEK_MT6360_ADC) += mt6360-adc.o obj-$(CONFIG_MEDIATEK_MT6370_ADC) += mt6370-adc.o diff --git a/drivers/iio/adc/mcp3564.c b/drivers/iio/adc/mcp3564.c new file mode 100644 index 000000000000..8c5649781093 --- /dev/null +++ b/drivers/iio/adc/mcp3564.c @@ -0,0 +1,1527 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * IIO driver for MCP356X/MCP356XR and MCP346X/MCP346XR series ADC chip family + * + * Copyright (C) 2022-2023 Microchip Technology Inc. and its subsidiaries + * + * Author: Marius Cristea <marius.cristea@xxxxxxxxxxxxx> + * + * Datasheet for MCP3561, MCP3562, MCP3564 can be found here: + * https://ww1.microchip.com/downloads/aemDocuments/documents/MSLD/ProductDocuments/DataSheets/MCP3561-2-4-Family-Data-Sheet-DS20006181C.pdf + * Datasheet for MCP3561R, MCP3562R, MCP3564R can be found here: + * https://ww1.microchip.com/downloads/aemDocuments/documents/APID/ProductDocuments/DataSheets/MCP3561_2_4R-Data-Sheet-DS200006391C.pdf + * Datasheet for MCP3461, MCP3462, MCP3464 can be found here: + * https://ww1.microchip.com/downloads/aemDocuments/documents/APID/ProductDocuments/DataSheets/MCP3461-2-4-Two-Four-Eight-Channel-153.6-ksps-Low-Noise-16-Bit-Delta-Sigma-ADC-Data-Sheet-20006180D.pdf + * Datasheet for MCP3461R, MCP3462R, MCP3464R can be found here: + * https://ww1.microchip.com/downloads/aemDocuments/documents/APID/ProductDocuments/DataSheets/MCP3461-2-4R-Family-Data-Sheet-DS20006404C.pdf + */ + +#include <linux/bitfield.h> +#include <linux/iopoll.h> +#include <linux/regulator/consumer.h> +#include <linux/spi/spi.h> +#include <linux/units.h> +#include <linux/util_macros.h> + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> + +#define MCP3564_ADCDATA_REG 0x00 + +#define MCP3564_CONFIG0_REG 0x01 +#define MCP3564_CONFIG0_ADC_MODE_MASK GENMASK(1, 0) +#define MCP3564_CONFIG0_ADC_MODE_MASK_SET(x) FIELD_PREP(MCP3564_CONFIG0_ADC_MODE_MASK, (x)) +/* Current Source/Sink Selection Bits for Sensor Bias */ +#define MCP3564_CONFIG0_CS_SEL_MASK GENMASK(3, 2) +#define MCP3564_CONFIG0_CS_SEL_SET(x) FIELD_PREP(MCP3564_CONFIG0_CS_SEL_MASK, (x)) +/* Internal clock is selected and AMCLK is present on the analog master clock output pin */ +#define MCP3564_CONFIG0_USE_INT_CLK_OUTPUT_EN 0x03 +/* Internal clock is selected and no clock output is present on the CLK pin */ +#define MCP3564_CONFIG0_USE_INT_CLK 0x02 +/* External digital clock */ +#define MCP3564_CONFIG0_USE_EXT_CLK 0x01 +/* External digital clock (default) */ +#define MCP3564_CONFIG0_USE_EXT_CLK_DEFAULT 0x00 +#define MCP3564_CONFIG0_CLK_SEL_MASK GENMASK(5, 4) +#define MCP3564_CONFIG0_CLK_SEL_SET(x) FIELD_PREP(MCP3564_CONFIG0_CLK_SEL_MASK, (x)) +#define MCP3456_CONFIG0_BIT6_DEFAULT BIT(6) +#define MCP3456_CONFIG0_VREF_MASK BIT(7) +#define MCP3564_CONFIG0_VREF_SET(x) FIELD_PREP(MCP3456_CONFIG0_VREF_MASK, (x)) + +#define MCP3564_CONFIG1_REG 0x02 +#define MCP3564_CONFIG1_OVERSPL_RATIO_MASK GENMASK(5, 2) +#define MCP3564_CONFIG1_OVERSPL_RATIO_SET(x) FIELD_PREP(MCP3564_CONFIG1_OVERSPL_RATIO_MASK, (x)) + +#define MCP3564_CONFIG2_REG 0x03 +#define MCP3564_CONFIG2_AZ_REF_MASK BIT(1) +#define MCP3564_CONFIG2_AZ_REF_SET(x) FIELD_PREP(MCP3564_CONFIG2_AZ_REF_MASK, (x)) +#define MCP3564_CONFIG2_AZ_MUX_MASK BIT(2) +#define MCP3564_CONFIG2_AZ_MUX_SET(x) FIELD_PREP(MCP3564_CONFIG2_AZ_MUX_MASK, (x)) + +#define MCP3564_CONFIG2_HARDWARE_GAIN_MASK GENMASK(5, 3) +#define MCP3564_CONFIG2_HARDWARE_GAIN_SET(x) FIELD_PREP(MCP3564_CONFIG2_HARDWARE_GAIN_MASK, (x)) +#define MCP3564_DEFAULT_HARDWARE_GAIN 0x01 +#define MCP3564_CONFIG2_BOOST_CURRENT_MASK GENMASK(7, 6) +#define MCP3564_CONFIG2_BOOST_CURRENT_SET(x) FIELD_PREP(MCP3564_CONFIG2_BOOST_CURRENT_MASK, (x)) + +#define MCP3564_CONFIG3_REG 0x04 +#define MCP3464_CONFIG3_EN_GAINCAL_MASK BIT(0) +#define MCP3464_CONFIG3_EN_OFFCAL_MASK BIT(1) +#define MCP3464_CONFIG3_EN_CRCCOM_MASK BIT(2) +#define MCP3464_CONFIG3_CRC_FORMAT_MASK BIT(3) +/* + * ADC Output Data Format 32-bit (25-bit right justified data + Channel ID): + * CHID[3:0] + SGN extension (4 bits) + 24-bit ADC data. + * It allows overrange with the SGN extension. + */ +#define MCP3464_CONFIG3_DATA_FMT_32B_WITH_CH_ID 3 +/* + * ADC Output Data Format 32-bit (25-bit right justified data): + * SGN extension (8-bit) + 24-bit ADC data. + * It allows overrange with the SGN extension. + */ +#define MCP3464_CONFIG3_DATA_FMT_32B_SGN_EXT 2 +/* + * ADC Output Data Format 32-bit (24-bit left justified data): + * 24-bit ADC data + 0x00 (8-bit). + * It does not allow overrange (ADC code locked to 0xFFFFFF or 0x800000). + */ +#define MCP3464_CONFIG3_DATA_FMT_32B_LEFT_JUSTIFIED 1 +/* + * ADC Output Data Format 24-bit (default ADC coding): + * 24-bit ADC data. + * It does not allow overrange (ADC code locked to 0xFFFFFF or 0x800000). + */ +#define MCP3464_CONFIG3_DATA_FMT_24B 0 +#define MCP3464_CONFIG3_DATA_FORMAT_MASK GENMASK(5, 4) +#define MCP3564_CONFIG3_DATA_FORMAT_SET(x) FIELD_PREP(MCP3464_CONFIG3_DATA_FORMAT_MASK, (x)) + +/* 0b11 = Continuous Conversion mode or continuous conversion cycle in SCAN mode. */ +#define MCP3464_CONFIG3_CONV_MODE_CONTINUOUS 3 +/* + * 0b10 = One-shot conversion or one-shot cycle in SCAN mode. It sets ADC_MODE[1:0] to ‘10’ + * (standby) at the end of the conversion or at the end of the conversion cycle in SCAN mode. + */ +#define MCP3464_CONFIG3_CONV_MODE_ONE_SHOT_STANDBY 2 +/* + * 0b0x = One-shot conversion or one-shot cycle in SCAN mode. It sets ADC_MODE[1:0] to ‘0x’ (ADC + * Shutdown) at the end of the conversion or at the end of the conversion cycle in SCAN + * mode (default). + */ +#define MCP3464_CONFIG3_CONV_MODE_ONE_SHOT_SHUTDOWN 0 +#define MCP3464_CONFIG3_CONV_MODE_MASK GENMASK(7, 6) +#define MCP3564_CONFIG3_CONV_MODE_SET(x) FIELD_PREP(MCP3464_CONFIG3_CONV_MODE_MASK, (x)) + +#define MCP3564_IRQ_REG 0x05 +#define MCP3464_EN_STP_MASK BIT(0) +#define MCP3464_EN_FASTCMD_MASK BIT(1) +#define MCP3464_IRQ_MODE_0_MASK BIT(2) +#define MCP3464_IRQ_MODE_1_MASK BIT(3) +#define MCP3564_POR_STATUS_MASK BIT(4) +#define MCP3564_CRCCFG_STATUS_MASK BIT(5) +#define MCP3564_DATA_READY_MASK BIT(6) + +#define MCP3564_MUX_REG 0x06 +#define MCP3564_MUX_VIN_P_MASK GENMASK(7, 4) +#define MCP3564_MUX_VIN_N_MASK GENMASK(3, 0) +#define MCP3564_MUX_SET(x, y) (FIELD_PREP(MCP3564_MUX_VIN_P_MASK, (x)) | \ + FIELD_PREP(MCP3564_MUX_VIN_N_MASK, (y))) + +#define MCP3564_SCAN_REG 0x07 +#define MCP3564_SCAN_CH_SEL_MASK GENMASK(15, 0) +#define MCP3564_SCAN_CH_SEL_SET(x) FIELD_PREP(MCP3564_SCAN_CH_SEL_MASK, (x)) +#define MCP3564_SCAN_DELAY_TIME_MASK GENMASK(23, 21) +#define MCP3564_SCAN_DELAY_TIME_SET(x) FIELD_PREP(MCP3564_SCAN_DELAY_TIME_MASK, (x)) +#define MCP3564_SCAN_DEFAULT_VALUE 0 + +#define MCP3564_TIMER_REG 0x08 +#define MCP3564_TIMER_DEFAULT_VALUE 0 + +#define MCP3564_OFFSETCAL_REG 0x09 +#define MCP3564_DEFAULT_OFFSETCAL 0 + +#define MCP3564_GAINCAL_REG 0x0A +#define MCP3564_DEFAULT_GAINCAL 0x00800000 + +#define MCP3564_RESERVED_B_REG 0x0B + +#define MCP3564_RESERVED_C_REG 0x0C +#define MCP3564_C_REG_DEFAULT 0x50 +#define MCP3564R_C_REG_DEFAULT 0x30 + +#define MCP3564_LOCK_REG 0x0D +#define MCP3564_LOCK_WRITE_ACCESS_PASSWORD 0xA5 +#define MCP3564_RESERVED_E_REG 0x0E +#define MCP3564_CRCCFG_REG 0x0F + +#define MCP3564_CMD_HW_ADDR_MASK GENMASK(7, 6) +#define MCP3564_CMD_HW_ADDR_SET(x) FIELD_PREP(MCP3564_CMD_HW_ADDR_MASK, (x)) +#define MCP3564_CMD_ADDR_MASK GENMASK(5, 2) +#define MCP3564_CMD_ADDR_SET(x) FIELD_PREP(MCP3564_CMD_ADDR_MASK, (x)) + +#define MCP3564_HW_ADDR_MASK GENMASK(1, 0) + +#define MCP3564_FASTCMD_START 0x0A +#define MCP3564_FASTCMD_RESET 0x0E + +#define MCP3461_HW_ID 0x0008 +#define MCP3462_HW_ID 0x0009 +#define MCP3464_HW_ID 0x000B + +#define MCP3561_HW_ID 0x000C +#define MCP3562_HW_ID 0x000D +#define MCP3564_HW_ID 0x000F +#define MCP3564_HW_ID_MASK GENMASK(3, 0) + +#define MCP3564R_INT_VREF_MV 2400 + +#define MCP3564_DATA_READY_TIMEOUT_MS 2000 + +#define MCP3564_MAX_PGA 8 +#define MCP3564_MAX_BURNOUT_IDX 4 +#define MCP3564_MAX_CHANNELS 66 + +enum mcp3564_ids { + mcp3461, + mcp3462, + mcp3464, + mcp3561, + mcp3562, + mcp3564, + mcp3461r, + mcp3462r, + mcp3464r, + mcp3561r, + mcp3562r, + mcp3564r, +}; + +enum mcp3564_delay_time { + MCP3564_NO_DELAY, + MCP3564_DELAY_8_DMCLK, + MCP3564_DELAY_16_DMCLK, + MCP3564_DELAY_32_DMCLK, + MCP3564_DELAY_64_DMCLK, + MCP3564_DELAY_128_DMCLK, + MCP3564_DELAY_256_DMCLK, + MCP3564_DELAY_512_DMCLK +}; + +enum mcp3564_adc_conversion_mode { + MCP3564_ADC_MODE_DEFAULT, + MCP3564_ADC_MODE_SHUTDOWN, + MCP3564_ADC_MODE_STANDBY, + MCP3564_ADC_MODE_CONVERSION +}; + +enum mcp3564_adc_bias_current { + MCP3564_BOOST_CURRENT_x0_50, + MCP3564_BOOST_CURRENT_x0_66, + MCP3564_BOOST_CURRENT_x1_00, + MCP3564_BOOST_CURRENT_x2_00 +}; + +enum mcp3564_burnout { + MCP3564_CONFIG0_CS_SEL_0_0_uA, + MCP3564_CONFIG0_CS_SEL_0_9_uA, + MCP3564_CONFIG0_CS_SEL_3_7_uA, + MCP3564_CONFIG0_CS_SEL_15_uA +}; + +enum mcp3564_channel_names { + MCP3564_CH0, + MCP3564_CH1, + MCP3564_CH2, + MCP3564_CH3, + MCP3564_CH4, + MCP3564_CH5, + MCP3564_CH6, + MCP3564_CH7, + MCP3564_AGND, + MCP3564_AVDD, + MCP3564_RESERVED, /* do not use */ + MCP3564_REFIN_POZ, + MCP3564_REFIN_NEG, + MCP3564_TEMP_DIODE_P, + MCP3564_TEMP_DIODE_M, + MCP3564_INTERNAL_VCM, +}; + +enum mcp3564_oversampling { + MCP3564_OVERSAMPLING_RATIO_32, + MCP3564_OVERSAMPLING_RATIO_64, + MCP3564_OVERSAMPLING_RATIO_128, + MCP3564_OVERSAMPLING_RATIO_256, + MCP3564_OVERSAMPLING_RATIO_512, + MCP3564_OVERSAMPLING_RATIO_1024, + MCP3564_OVERSAMPLING_RATIO_2048, + MCP3564_OVERSAMPLING_RATIO_4096, + MCP3564_OVERSAMPLING_RATIO_8192, + MCP3564_OVERSAMPLING_RATIO_16384, + MCP3564_OVERSAMPLING_RATIO_20480, + MCP3564_OVERSAMPLING_RATIO_24576, + MCP3564_OVERSAMPLING_RATIO_40960, + MCP3564_OVERSAMPLING_RATIO_49152, + MCP3564_OVERSAMPLING_RATIO_81920, + MCP3564_OVERSAMPLING_RATIO_98304 +}; + +static const unsigned int mcp3564_oversampling_avail[] = { + [MCP3564_OVERSAMPLING_RATIO_32] = 32, + [MCP3564_OVERSAMPLING_RATIO_64] = 64, + [MCP3564_OVERSAMPLING_RATIO_128] = 128, + [MCP3564_OVERSAMPLING_RATIO_256] = 256, + [MCP3564_OVERSAMPLING_RATIO_512] = 512, + [MCP3564_OVERSAMPLING_RATIO_1024] = 1024, + [MCP3564_OVERSAMPLING_RATIO_2048] = 2048, + [MCP3564_OVERSAMPLING_RATIO_4096] = 4096, + [MCP3564_OVERSAMPLING_RATIO_8192] = 8192, + [MCP3564_OVERSAMPLING_RATIO_16384] = 16384, + [MCP3564_OVERSAMPLING_RATIO_20480] = 20480, + [MCP3564_OVERSAMPLING_RATIO_24576] = 24576, + [MCP3564_OVERSAMPLING_RATIO_40960] = 40960, + [MCP3564_OVERSAMPLING_RATIO_49152] = 49152, + [MCP3564_OVERSAMPLING_RATIO_81920] = 81920, + [MCP3564_OVERSAMPLING_RATIO_98304] = 98304 +}; + +/* + * Current Source/Sink Selection Bits for Sensor Bias (source on VIN+/sink on VIN-) + */ +static const int mcp3564_burnout_avail[][2] = { + [MCP3564_CONFIG0_CS_SEL_0_0_uA] = {0, 0}, + [MCP3564_CONFIG0_CS_SEL_0_9_uA] = {0, 900}, + [MCP3564_CONFIG0_CS_SEL_3_7_uA] = {0, 3700}, + [MCP3564_CONFIG0_CS_SEL_15_uA] = {0, 15000} +}; + +/* + * BOOST[1:0]: ADC Bias Current Selection + */ +static const char * const mcp3564_boost_current_avail[] = { + [MCP3564_BOOST_CURRENT_x0_50] = "0.5", + [MCP3564_BOOST_CURRENT_x0_66] = "0.66", + [MCP3564_BOOST_CURRENT_x1_00] = "1", + [MCP3564_BOOST_CURRENT_x2_00] = "2", +}; + +/* + * Calibration bias values + */ +static const int mcp3564_calib_bias[] = { + -8388608, /* min: -2^23 */ + 1, /* step: 1 */ + 8388607 /* max: 2^23 - 1 */ +}; + +/* + * Calibration scale values + * The Gain Error Calibration register (GAINCAL) is an + * unsigned 24-bit register that holds the digital gain error + * calibration value, GAINCAL which could be calculated by + * GAINCAL (V/V) = (GAINCAL[23:0])/8388608 + * The gain error calibration value range in equivalent voltage is [0; 2-2^(-23)] + */ +static const unsigned int mcp3564_calib_scale[] = { + 0, /* min: 0 */ + 1, /* step: 1/8388608 */ + 16777215 /* max: 2 - 2^(-23) */ +}; + +/* Programmable hardware gain x1/3, x1, x2, x4, x8, x16, x32, x64 */ +static const int mcp3564_hwgain_frac[] = { + 3, 10, + 1, 1, + 2, 1, + 4, 1, + 8, 1, + 16, 1, + 32, 1, + 64, 1 +}; + +static const char *mcp3564_channel_labels[2] = { + "burnout_current", "temperature", +}; + +/** + * struct mcp3564_chip_info - chip specific data + * @name: device name + * @num_channels: number of channels + * @resolution: ADC resolution + * @has_vref: does the hardware has an internal voltage reference? + */ +struct mcp3564_chip_info { + const char *name; + unsigned int num_channels; + unsigned int resolution; + bool has_vref; +}; + +/** + * struct mcp3564_state - working data for a ADC device + * @chip_info: chip specific data + * @spi: SPI device structure + * @vref: the regulator device used as a voltage reference in case + * external voltage reference is used + * @vref_mv: voltage reference value in miliVolts + * @lock: synchronize access to driver's state members + * @dev_addr: hardware device address + * @oversampling: the index inside oversampling list of the ADC + * @hwgain: the index inside hardware gain list of the ADC + * @scale_tbls: table with precalculated scale + * @calib_bias: calibration bias value + * @calib_scale: calibration scale value + * @current_boost_mode: the index inside current boost list of the ADC + * @burnout_mode: the index inside current bias list of the ADC + * @auto_zeroing_mux: set if ADC auto-zeroing algorithm is enabled + * @auto_zeroing_ref: set if ADC auto-Zeroing Reference Buffer Setting is enabled + * @has_vref: does the ADC has an internal voltage reference? + * @labels: table with channels labels + */ +struct mcp3564_state { + const struct mcp3564_chip_info *chip_info; + struct spi_device *spi; + struct regulator *vref; + unsigned short vref_mv; + struct mutex lock; /* Synchronize access to driver's state members */ + u8 dev_addr; + enum mcp3564_oversampling oversampling; + unsigned int hwgain; + unsigned int scale_tbls[MCP3564_MAX_PGA][2]; + int calib_bias; + int calib_scale; + unsigned int current_boost_mode; + enum mcp3564_burnout burnout_mode; + bool auto_zeroing_mux; + bool auto_zeroing_ref; + bool has_vref; + const char *labels[MCP3564_MAX_CHANNELS]; +}; + +static inline u8 mcp3564_cmd_write(u8 chip_addr, u8 reg) +{ + return MCP3564_CMD_HW_ADDR_SET(chip_addr) | MCP3564_CMD_ADDR_SET(reg) | BIT(1); +} + +static inline u8 mcp3564_cmd_read(u8 chip_addr, u8 reg) +{ + return MCP3564_CMD_HW_ADDR_SET(chip_addr) | MCP3564_CMD_ADDR_SET(reg) | BIT(0); +} + +static int mcp3564_read_8bits(struct mcp3564_state *adc, u8 reg, u8 *val) +{ + int ret; + u8 tx_buf; + u8 rx_buf; + + tx_buf = mcp3564_cmd_read(adc->dev_addr, reg); + + ret = spi_write_then_read(adc->spi, &tx_buf, sizeof(tx_buf), + &rx_buf, sizeof(rx_buf)); + *val = rx_buf; + + return ret; +} + +static int mcp3564_read_16bits(struct mcp3564_state *adc, u8 reg, u16 *val) +{ + int ret; + u8 tx_buf; + __be16 rx_buf; + + tx_buf = mcp3564_cmd_read(adc->dev_addr, reg); + + ret = spi_write_then_read(adc->spi, &tx_buf, sizeof(tx_buf), + &rx_buf, sizeof(rx_buf)); + *val = be16_to_cpu(rx_buf); + + return ret; +} + +static int mcp3564_read_32bits(struct mcp3564_state *adc, u8 reg, u32 *val) +{ + int ret; + u8 tx_buf; + __be32 rx_buf; + + tx_buf = mcp3564_cmd_read(adc->dev_addr, reg); + + ret = spi_write_then_read(adc->spi, &tx_buf, sizeof(tx_buf), + &rx_buf, sizeof(rx_buf)); + *val = be32_to_cpu(rx_buf); + + return ret; +} + +static int mcp3564_write_8bits(struct mcp3564_state *adc, u8 reg, u8 val) +{ + u8 tmp; + u8 tx_buf[2]; + + tx_buf[0] = mcp3564_cmd_write(adc->dev_addr, reg); + tx_buf[1] = val; + + return spi_write_then_read(adc->spi, tx_buf, sizeof(tx_buf), &tmp, 0); +} + +static int mcp3564_write_24bits(struct mcp3564_state *adc, u8 reg, u32 val) +{ + u8 tmp; + __be32 val_be; + + val |= (mcp3564_cmd_write(adc->dev_addr, reg) << 24); + val_be = cpu_to_be32(val); + + return spi_write_then_read(adc->spi, &val_be, sizeof(val_be), &tmp, 0); +} + +static int mcp3564_fast_cmd(struct mcp3564_state *adc, u8 fast_cmd) +{ + u8 val; + u8 tmp; + + val = MCP3564_CMD_HW_ADDR_SET(adc->dev_addr) | MCP3564_CMD_ADDR_SET(fast_cmd); + + return spi_write_then_read(adc->spi, &val, 1, &tmp, 0); +} + +static int mcp3564_update_8bits(struct mcp3564_state *adc, u8 reg, u32 mask, u8 val) +{ + u8 tmp; + int ret; + + ret = mcp3564_read_8bits(adc, reg, &tmp); + if (ret < 0) + return ret; + + val &= mask; + val |= tmp & ~mask; + ret = mcp3564_write_8bits(adc, reg, val); + + return ret; +} + +static int mcp3564_set_current_boost_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + unsigned int mode) +{ + struct mcp3564_state *adc = iio_priv(indio_dev); + int ret; + + dev_dbg(&indio_dev->dev, "%s: %d\n", __func__, mode); + + mutex_lock(&adc->lock); + ret = mcp3564_update_8bits(adc, MCP3564_CONFIG2_REG, MCP3564_CONFIG2_BOOST_CURRENT_MASK, + MCP3564_CONFIG2_BOOST_CURRENT_SET(mode)); + + if (ret) + dev_err(&indio_dev->dev, "Failed to configure CONFIG2 register\n"); + else + adc->current_boost_mode = mode; + + mutex_unlock(&adc->lock); + + return ret; +} + +static int mcp3564_get_current_boost_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan) +{ + struct mcp3564_state *adc = iio_priv(indio_dev); + + return adc->current_boost_mode; +} + +static const struct iio_enum mcp3564_current_boost_mode_enum = { + .items = mcp3564_boost_current_avail, + .num_items = ARRAY_SIZE(mcp3564_boost_current_avail), + .set = mcp3564_set_current_boost_mode, + .get = mcp3564_get_current_boost_mode, +}; + +static const struct iio_chan_spec_ext_info mcp3564_ext_info[] = { + IIO_ENUM("boost_current_gain", IIO_SHARED_BY_ALL, &mcp3564_current_boost_mode_enum), + { + .name = "boost_current_gain_available", + .shared = IIO_SHARED_BY_ALL, + .read = iio_enum_available_read, + .private = (uintptr_t)&mcp3564_current_boost_mode_enum, + }, + { } +}; + +static ssize_t mcp3564_auto_zeroing_mux_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct mcp3564_state *adc = iio_priv(indio_dev); + + return sysfs_emit(buf, "%d\n", adc->auto_zeroing_mux); +} + +static ssize_t mcp3564_auto_zeroing_mux_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct mcp3564_state *adc = iio_priv(indio_dev); + bool auto_zero; + int ret; + + ret = kstrtobool(buf, &auto_zero); + if (ret) + return ret; + + mutex_lock(&adc->lock); + ret = mcp3564_update_8bits(adc, MCP3564_CONFIG2_REG, MCP3564_CONFIG2_AZ_MUX_MASK, + MCP3564_CONFIG2_AZ_MUX_SET(auto_zero)); + + if (ret) + dev_err(&indio_dev->dev, "Failed to update CONFIG2 register\n"); + else + adc->auto_zeroing_mux = auto_zero; + + mutex_unlock(&adc->lock); + + return ret ? ret : len; +} + +static ssize_t mcp3564_auto_zeroing_ref_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct mcp3564_state *adc = iio_priv(indio_dev); + + return sysfs_emit(buf, "%d\n", adc->auto_zeroing_ref); +} + +static ssize_t mcp3564_auto_zeroing_ref_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct mcp3564_state *adc = iio_priv(indio_dev); + bool auto_zero; + int ret; + + ret = kstrtobool(buf, &auto_zero); + if (ret) + return ret; + + mutex_lock(&adc->lock); + ret = mcp3564_update_8bits(adc, MCP3564_CONFIG2_REG, MCP3564_CONFIG2_AZ_REF_MASK, + MCP3564_CONFIG2_AZ_REF_SET(auto_zero)); + + if (ret) + dev_err(&indio_dev->dev, "Failed to update CONFIG2 register\n"); + else + adc->auto_zeroing_ref = auto_zero; + + mutex_unlock(&adc->lock); + + return ret ? ret : len; +} + +static const struct iio_chan_spec mcp3564_channel_template = { + .type = IIO_VOLTAGE, + .indexed = 1, + .differential = 1, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_CALIBSCALE) | + BIT(IIO_CHAN_INFO_CALIBBIAS) | + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), + .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_CALIBSCALE) | + BIT(IIO_CHAN_INFO_CALIBBIAS) | + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), + .ext_info = mcp3564_ext_info, +}; + +static const struct iio_chan_spec mcp3564_temp_channel_template = { + .type = IIO_TEMP, + .channel = 0, + .address = ((MCP3564_TEMP_DIODE_P << 4) | MCP3564_TEMP_DIODE_M), + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_CALIBSCALE) | + BIT(IIO_CHAN_INFO_CALIBBIAS) | + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), + .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_CALIBSCALE) | + BIT(IIO_CHAN_INFO_CALIBBIAS) | + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), +}; + +static const struct iio_chan_spec mcp3564_burnout_channel_template = { + .type = IIO_CURRENT, + .output = true, + .channel = 0, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW), +}; + +/* + * Number of channels could be calculated: + * num_channels = single_ended_input + differential_input + temperature + burnout + * Eg. for MCP3561 (only 2 channels available: CH0 and CH1) + * single_ended_input = (CH0 - GND), (CH1 - GND) = 2 + * differential_input = (CH0 - CH1), (CH0 - CH0) = 2 + * num_channels = 2 + 2 + 2 + * Generic formula is: + * num_channels = P^R(Number_of_single_ended_channels, 2) + 2 (temperature + burnout channels) + * P^R(Number_of_single_ended_channels, 2) is Permutations with Replacement of + * Number_of_single_ended_channels taken by 2 + */ +static const struct mcp3564_chip_info mcp3564_chip_infos_tbl[] = { + [mcp3461] = { + .name = "mcp3461", + .num_channels = 6, + .resolution = 16, + .has_vref = false, + }, + [mcp3462] = { + .name = "mcp3462", + .num_channels = 18, + .resolution = 16, + .has_vref = false, + }, + [mcp3464] = { + .name = "mcp3464", + .num_channels = 66, + .resolution = 16, + .has_vref = false, + }, + [mcp3561] = { + .name = "mcp3561", + .num_channels = 6, + .resolution = 24, + .has_vref = false, + }, + [mcp3562] = { + .name = "mcp3562", + .num_channels = 18, + .resolution = 24, + .has_vref = false, + }, + [mcp3564] = { + .name = "mcp3564", + .num_channels = 66, + .resolution = 24, + .has_vref = false, + }, + [mcp3461r] = { + .name = "mcp3461r", + .num_channels = 6, + .resolution = 16, + .has_vref = false, + }, + [mcp3462r] = { + .name = "mcp3462r", + .num_channels = 18, + .resolution = 16, + .has_vref = true, + }, + [mcp3464r] = { + .name = "mcp3464r", + .num_channels = 66, + .resolution = 16, + .has_vref = true, + }, + [mcp3561r] = { + .name = "mcp3561r", + .num_channels = 6, + .resolution = 24, + .has_vref = true, + }, + [mcp3562r] = { + .name = "mcp3562r", + .num_channels = 18, + .resolution = 24, + .has_vref = true, + }, + [mcp3564r] = { + .name = "mcp3564r", + .num_channels = 66, + .resolution = 24, + .has_vref = true, + }, +}; + +static int mcp3564_read_single_value(struct iio_dev *indio_dev, + struct iio_chan_spec const *channel, + int *val) +{ + struct mcp3564_state *adc = iio_priv(indio_dev); + int ret; + u8 tmp; + int ret_read = 0; + + ret = mcp3564_write_8bits(adc, MCP3564_MUX_REG, channel->address); + if (ret) + return ret; + + /* Start ADC Conversion using fast command (overwrites ADC_MODE[1:0] = 11) */ + ret = mcp3564_fast_cmd(adc, MCP3564_FASTCMD_START); + if (ret) + return ret; + + /* + * Check if the conversion is ready. If not, wait a little bit, and + * in case of timeout exit with an error. + */ + ret = read_poll_timeout(mcp3564_read_8bits, ret_read, + ret_read || !(tmp & MCP3564_DATA_READY_MASK), + 20000, MCP3564_DATA_READY_TIMEOUT_MS * 1000, true, + adc, MCP3564_IRQ_REG, &tmp); + + /* failed to read status register */ + if (ret_read) + return ret_read; + + if (ret) + return ret; + + if (tmp & MCP3564_DATA_READY_MASK) + /* failing to finish conversion */ + return -EBUSY; + + return mcp3564_read_32bits(adc, MCP3564_ADCDATA_REG, val); +} + +static int mcp3564_read_avail(struct iio_dev *indio_dev, + struct iio_chan_spec const *channel, + const int **vals, int *type, + int *length, long mask) +{ + struct mcp3564_state *adc = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_RAW: + if (!channel->output) + return -EINVAL; + + *vals = mcp3564_burnout_avail[0]; + *length = ARRAY_SIZE(mcp3564_burnout_avail) * 2; + *type = IIO_VAL_INT_PLUS_MICRO; + return IIO_AVAIL_LIST; + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + *vals = mcp3564_oversampling_avail; + *length = ARRAY_SIZE(mcp3564_oversampling_avail); + *type = IIO_VAL_INT; + return IIO_AVAIL_LIST; + case IIO_CHAN_INFO_SCALE: + *vals = (int *)adc->scale_tbls; + *length = ARRAY_SIZE(adc->scale_tbls) * 2; + *type = IIO_VAL_INT_PLUS_NANO; + return IIO_AVAIL_LIST; + case IIO_CHAN_INFO_CALIBBIAS: + *vals = mcp3564_calib_bias; + *type = IIO_VAL_INT; + return IIO_AVAIL_RANGE; + case IIO_CHAN_INFO_CALIBSCALE: + *vals = mcp3564_calib_scale; + *type = IIO_VAL_INT; + return IIO_AVAIL_RANGE; + default: + return -EINVAL; + } +} + +static int mcp3564_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *channel, + int *val, int *val2, long mask) +{ + struct mcp3564_state *adc = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + if (channel->output) { + mutex_lock(&adc->lock); + *val = mcp3564_burnout_avail[adc->burnout_mode][0]; + *val2 = mcp3564_burnout_avail[adc->burnout_mode][1]; + mutex_unlock(&adc->lock); + return IIO_VAL_INT_PLUS_MICRO; + } + + ret = mcp3564_read_single_value(indio_dev, channel, val); + if (ret) + return -EINVAL; + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + mutex_lock(&adc->lock); + *val = adc->scale_tbls[adc->hwgain][0]; + *val2 = adc->scale_tbls[adc->hwgain][1]; + mutex_unlock(&adc->lock); + return IIO_VAL_INT_PLUS_NANO; + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + *val = mcp3564_oversampling_avail[adc->oversampling]; + return IIO_VAL_INT; + case IIO_CHAN_INFO_CALIBBIAS: + *val = adc->calib_bias; + return IIO_VAL_INT; + case IIO_CHAN_INFO_CALIBSCALE: + *val = adc->calib_scale; + return IIO_VAL_INT; + default: + return -EINVAL; + } +} + +static int mcp3564_write_raw_get_fmt(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + long info) +{ + switch (info) { + case IIO_CHAN_INFO_RAW: + return IIO_VAL_INT_PLUS_MICRO; + case IIO_CHAN_INFO_CALIBBIAS: + case IIO_CHAN_INFO_CALIBSCALE: + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + return IIO_VAL_INT_PLUS_NANO; + default: + return -EINVAL; + } +} + +static int mcp3564_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *channel, int val, + int val2, long mask) +{ + struct mcp3564_state *adc = iio_priv(indio_dev); + int tmp; + unsigned int hwgain; + enum mcp3564_burnout burnout; + int ret = 0; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + if (!channel->output) + return -EINVAL; + + for (burnout = 0; burnout < MCP3564_MAX_BURNOUT_IDX; burnout++) { + if (val == mcp3564_burnout_avail[burnout][0] && + val2 == mcp3564_burnout_avail[burnout][1]) + break; + } + + if (burnout == MCP3564_MAX_BURNOUT_IDX) + return -EINVAL; + + if (burnout == adc->burnout_mode) + return ret; + + mutex_lock(&adc->lock); + ret = mcp3564_update_8bits(adc, MCP3564_CONFIG0_REG, + MCP3564_CONFIG0_CS_SEL_MASK, + MCP3564_CONFIG0_CS_SEL_SET(burnout)); + + if (ret) + dev_err(&indio_dev->dev, "Failed to configure burnout current\n"); + else + adc->burnout_mode = burnout; + mutex_unlock(&adc->lock); + return ret; + case IIO_CHAN_INFO_CALIBBIAS: + if (val < mcp3564_calib_bias[0] && val > mcp3564_calib_bias[2]) + return -EINVAL; + + mutex_lock(&adc->lock); + ret = mcp3564_write_24bits(adc, MCP3564_OFFSETCAL_REG, val); + if (!ret) + adc->calib_bias = val; + mutex_unlock(&adc->lock); + return ret; + case IIO_CHAN_INFO_CALIBSCALE: + if (val < mcp3564_calib_scale[0] && val > mcp3564_calib_scale[2]) + return -EINVAL; + + if (adc->calib_scale == val) + return ret; + + mutex_lock(&adc->lock); + ret = mcp3564_write_24bits(adc, MCP3564_GAINCAL_REG, val); + if (!ret) + adc->calib_scale = val; + mutex_unlock(&adc->lock); + return ret; + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + if (val < 0) + return -EINVAL; + + tmp = find_closest(val, mcp3564_oversampling_avail, + ARRAY_SIZE(mcp3564_oversampling_avail)); + + if (adc->oversampling == tmp) + return ret; + + mutex_lock(&adc->lock); + ret = mcp3564_update_8bits(adc, MCP3564_CONFIG1_REG, + MCP3564_CONFIG1_OVERSPL_RATIO_MASK, + MCP3564_CONFIG1_OVERSPL_RATIO_SET(adc->oversampling)); + if (!ret) + adc->oversampling = tmp; + mutex_unlock(&adc->lock); + return ret; + case IIO_CHAN_INFO_SCALE: + for (hwgain = 0; hwgain < MCP3564_MAX_PGA; hwgain++) { + if (val == adc->scale_tbls[hwgain][0] && + val2 == adc->scale_tbls[hwgain][1]) + break; + } + + if (hwgain == MCP3564_MAX_PGA) + return -EINVAL; + + if (hwgain == adc->hwgain) + return ret; + + mutex_lock(&adc->lock); + /* Update GAIN in CONFIG2[5:3] -> GAIN[2:0]*/ + ret = mcp3564_update_8bits(adc, MCP3564_CONFIG2_REG, + MCP3564_CONFIG2_HARDWARE_GAIN_MASK, + MCP3564_CONFIG2_HARDWARE_GAIN_SET(hwgain)); + if (!ret) + adc->hwgain = hwgain; + + mutex_unlock(&adc->lock); + return ret; + default: + return -EINVAL; + } +} + +static int mcp3564_read_label(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, char *label) +{ + struct mcp3564_state *adc = iio_priv(indio_dev); + + return sprintf(label, "%s\n", adc->labels[chan->scan_index]); +} + +static int mcp3564_parse_fw_children(struct iio_dev *indio_dev) +{ + struct mcp3564_state *adc = iio_priv(indio_dev); + struct device *dev = &adc->spi->dev; + struct iio_chan_spec *channels; + struct fwnode_handle *child; + struct iio_chan_spec chanspec = mcp3564_channel_template; + struct iio_chan_spec temp_chanspec = mcp3564_temp_channel_template; + struct iio_chan_spec burnout_chanspec = mcp3564_burnout_channel_template; + int chan_idx = 0; + unsigned int num_ch; + u32 inputs[2]; + const char *node_name; + const char *label; + int ret; + + num_ch = device_get_child_node_count(dev); + if (num_ch == 0) + return dev_err_probe(&indio_dev->dev, -ENODEV, + "FW has no channels defined\n"); + + /* Reserve space for burnout and temperature channel */ + num_ch += 2; + + if (num_ch > adc->chip_info->num_channels) { + return dev_err_probe(dev, -EINVAL, "Too many channels %d > %d\n", + num_ch, adc->chip_info->num_channels); + } + + channels = devm_kcalloc(dev, num_ch, sizeof(*channels), GFP_KERNEL); + if (!channels) + return dev_err_probe(dev, -ENOMEM, "Can't allocate memory\n"); + + device_for_each_child_node(dev, child) { + node_name = fwnode_get_name(child); + + if (fwnode_property_present(child, "diff-channels")) { + ret = fwnode_property_read_u32_array(child, + "diff-channels", + inputs, + ARRAY_SIZE(inputs)); + chanspec.differential = 1; + } else { + ret = fwnode_property_read_u32(child, "reg", &inputs[0]); + + chanspec.differential = 0; + inputs[1] = MCP3564_AGND; + } + if (ret) { + fwnode_handle_put(child); + return ret; + } + + if (inputs[0] > MCP3564_INTERNAL_VCM || + inputs[1] > MCP3564_INTERNAL_VCM) { + fwnode_handle_put(child); + return dev_err_probe(&indio_dev->dev, -EINVAL, + "Channel index > %d, for %s\n", + MCP3564_INTERNAL_VCM + 1, + node_name); + } + + chanspec.address = (inputs[0] << 4) | inputs[1]; + chanspec.channel = inputs[0]; + chanspec.channel2 = inputs[1]; + chanspec.scan_index = chan_idx; + + if (fwnode_property_present(child, "label")) { + fwnode_property_read_string(child, "label", &label); + adc->labels[chan_idx] = label; + } + + channels[chan_idx] = chanspec; + chan_idx++; + } + + /* Add burnout current channel */ + burnout_chanspec.scan_index = chan_idx; + channels[chan_idx] = burnout_chanspec; + adc->labels[chan_idx] = mcp3564_channel_labels[0]; + chanspec.scan_index = chan_idx; + chan_idx++; + + /* Add temperature channel */ + temp_chanspec.scan_index = chan_idx; + channels[chan_idx] = temp_chanspec; + adc->labels[chan_idx] = mcp3564_channel_labels[1]; + chan_idx++; + + indio_dev->num_channels = chan_idx; + indio_dev->channels = channels; + + return 0; +} + +static void mcp3564_disable_reg(void *reg) +{ + regulator_disable(reg); +} + +static void mcp3564_fill_scale_tbls(struct mcp3564_state *adc) +{ + unsigned int pow = adc->chip_info->resolution - 1; + int ref; + unsigned int i; + int tmp0; + u64 tmp1; + + for (i = 0; i < MCP3564_MAX_PGA; i++) { + ref = adc->vref_mv; + tmp1 = shift_right((u64)ref * NANO, pow); + div_u64_rem(tmp1, NANO, &tmp0); + + tmp1 = tmp1 * mcp3564_hwgain_frac[(2 * i) + 1]; + tmp0 = (int)div_u64(tmp1, mcp3564_hwgain_frac[2 * i]); + + adc->scale_tbls[i][1] = tmp0; + } +} + +static int mcp3564_config(struct iio_dev *indio_dev) +{ + struct mcp3564_state *adc = iio_priv(indio_dev); + struct device *dev = &adc->spi->dev; + const struct spi_device_id *dev_id; + u8 tmp_reg; + u16 tmp_u16; + enum mcp3564_ids ids; + int ret = 0; + unsigned int tmp = 0x01; + bool err = true; + + /* + * The address is set on a per-device basis by fuses in the factory, + * configured on request. If not requested, the fuses are set for 0x1. + * The device address is part of the device markings to avoid + * potential confusion. This address is coded on two bits, so four possible + * addresses are available when multiple devices are present on the same + * SPI bus with only one Chip Select line for all devices. + */ + device_property_read_u32(dev, "microchip,hw-device-address", &tmp); + + if (tmp > 3) { + dev_err_probe(dev, tmp, + "invalid device address. Must be in range 0-3.\n"); + return -EINVAL; + } + + adc->dev_addr = MCP3564_HW_ADDR_MASK & tmp; + + dev_dbg(dev, "use device address %i\n", adc->dev_addr); + + ret = mcp3564_read_8bits(adc, MCP3564_RESERVED_C_REG, &tmp_reg); + if (ret < 0) + return ret; + + switch (tmp_reg) { + case MCP3564_C_REG_DEFAULT: + adc->has_vref = false; + break; + case MCP3564R_C_REG_DEFAULT: + adc->has_vref = true; + break; + default: + dev_info(dev, "Unknown chip found: %d\n", tmp_reg); + err = true; + } + + if (!err) { + ret = mcp3564_read_16bits(adc, MCP3564_RESERVED_E_REG, &tmp_u16); + if (ret < 0) + return ret; + + switch (tmp_u16 & MCP3564_HW_ID_MASK) { + case MCP3461_HW_ID: + if (adc->has_vref) + ids = mcp3461r; + else + ids = mcp3461; + break; + case MCP3462_HW_ID: + if (adc->has_vref) + ids = mcp3462r; + else + ids = mcp3462; + break; + case MCP3464_HW_ID: + if (adc->has_vref) + ids = mcp3464r; + else + ids = mcp3464; + break; + case MCP3561_HW_ID: + if (adc->has_vref) + ids = mcp3561r; + else + ids = mcp3561; + break; + case MCP3562_HW_ID: + if (adc->has_vref) + ids = mcp3562r; + else + ids = mcp3562; + break; + case MCP3564_HW_ID: + if (adc->has_vref) + ids = mcp3564r; + else + ids = mcp3564; + break; + default: + dev_info(dev, "Unknown chip found: %d\n", tmp_u16); + err = true; + } + } + + if (err) { + /* + * If failed to identify the hardware based on internal registers, + * try using fallback compatible in device tree to deal with some newer part number. + */ + adc->chip_info = spi_get_device_match_data(adc->spi); + if (!adc->chip_info) { + dev_id = spi_get_device_id(adc->spi); + adc->chip_info = (const struct mcp3564_chip_info *)dev_id->driver_data; + } + + adc->has_vref = adc->chip_info->has_vref; + } else { + adc->chip_info = &mcp3564_chip_infos_tbl[ids]; + } + + dev_dbg(dev, "Found %s chip\n", adc->chip_info->name); + + adc->vref = devm_regulator_get_optional(dev, "vref"); + if (IS_ERR(adc->vref)) { + if (IS_ERR(adc->vref)) { + /* Check if chip has internal vref */ + if (!adc->has_vref) + return dev_err_probe(dev, PTR_ERR(adc->vref), + "Unknown Vref\n"); + adc->vref = NULL; + dev_dbg(dev, "%s: Using internal Vref\n", __func__); + } else { + return dev_err_probe(dev, PTR_ERR(adc->vref), + "failed to get regulator\n"); + } + } else { + ret = regulator_enable(adc->vref); + if (ret) + return ret; + + ret = devm_add_action_or_reset(dev, mcp3564_disable_reg, + adc->vref); + if (ret) + return ret; + + dev_dbg(dev, "%s: Using External Vref\n", __func__); + + ret = regulator_get_voltage(adc->vref); + if (ret < 0) { + return dev_err_probe(dev, ret, + "Failed to read vref regulator\n"); + } + + adc->vref_mv = ret / MILLI; + } + + ret = mcp3564_parse_fw_children(indio_dev); + if (ret) + return ret; + + /* + * Command sequence that ensures a recovery with the desired settings + * in any cases of loss-of-power scenario (Full Chip Reset): + * - Write LOCK register to 0xA5 + * - Write IRQ register to 0x03 + * - Send "Device Full Reset" fast command + * - Wait 1ms for "Full Reset" to complete + */ + ret = mcp3564_write_8bits(adc, MCP3564_LOCK_REG, MCP3564_LOCK_WRITE_ACCESS_PASSWORD); + if (ret) + return ret; + + ret = mcp3564_write_8bits(adc, MCP3564_IRQ_REG, 0x03); + if (ret) + return ret; + + ret = mcp3564_fast_cmd(adc, MCP3564_FASTCMD_RESET); + if (ret) + return ret; + + mdelay(1); + + /* set a gain of 1x for GAINCAL */ + ret = mcp3564_write_24bits(adc, MCP3564_GAINCAL_REG, MCP3564_DEFAULT_GAINCAL); + if (ret) + return ret; + + adc->calib_scale = MCP3564_DEFAULT_GAINCAL; + + ret = mcp3564_write_24bits(adc, MCP3564_OFFSETCAL_REG, MCP3564_DEFAULT_OFFSETCAL); + if (ret) + return ret; + + ret = mcp3564_write_24bits(adc, MCP3564_TIMER_REG, MCP3564_TIMER_DEFAULT_VALUE); + if (ret) + return ret; + + ret = mcp3564_write_24bits(adc, MCP3564_SCAN_REG, + MCP3564_SCAN_DELAY_TIME_SET(MCP3564_NO_DELAY) | + MCP3564_SCAN_CH_SEL_SET(MCP3564_SCAN_DEFAULT_VALUE)); + if (ret) + return ret; + + ret = mcp3564_write_8bits(adc, MCP3564_MUX_REG, MCP3564_MUX_SET(MCP3564_CH0, MCP3564_CH1)); + if (ret) + return ret; + + ret = mcp3564_write_8bits(adc, MCP3564_IRQ_REG, + FIELD_PREP(MCP3464_EN_FASTCMD_MASK, 1) | + FIELD_PREP(MCP3464_EN_STP_MASK, 1)); + if (ret) + return ret; + + tmp_reg = MCP3564_CONFIG3_CONV_MODE_SET(MCP3464_CONFIG3_CONV_MODE_ONE_SHOT_STANDBY); + tmp_reg |= MCP3564_CONFIG3_DATA_FORMAT_SET(MCP3464_CONFIG3_DATA_FMT_32B_SGN_EXT); + tmp_reg |= MCP3464_CONFIG3_EN_OFFCAL_MASK; + tmp_reg |= MCP3464_CONFIG3_EN_GAINCAL_MASK; + + ret = mcp3564_write_8bits(adc, MCP3564_CONFIG3_REG, tmp_reg); + if (ret) + return ret; + + tmp_reg = MCP3564_CONFIG2_BOOST_CURRENT_SET(MCP3564_BOOST_CURRENT_x1_00); + tmp_reg |= MCP3564_CONFIG2_HARDWARE_GAIN_SET(0x01); + tmp_reg |= MCP3564_CONFIG2_AZ_MUX_SET(1); + + ret = mcp3564_write_8bits(adc, MCP3564_CONFIG2_REG, tmp_reg); + if (ret) + return ret; + + adc->hwgain = 0x01; + adc->auto_zeroing_mux = true; + adc->auto_zeroing_ref = false; + adc->current_boost_mode = MCP3564_BOOST_CURRENT_x1_00; + + tmp_reg = MCP3564_CONFIG1_OVERSPL_RATIO_SET(MCP3564_OVERSAMPLING_RATIO_98304); + + ret = mcp3564_write_8bits(adc, MCP3564_CONFIG1_REG, tmp_reg); + if (ret) + return ret; + + adc->oversampling = MCP3564_OVERSAMPLING_RATIO_98304; + + tmp_reg = MCP3564_CONFIG0_ADC_MODE_MASK_SET(MCP3564_ADC_MODE_STANDBY); + tmp_reg |= MCP3564_CONFIG0_CS_SEL_SET(MCP3564_CONFIG0_CS_SEL_0_0_uA); + tmp_reg |= MCP3564_CONFIG0_CLK_SEL_SET(MCP3564_CONFIG0_USE_INT_CLK); + tmp_reg |= MCP3456_CONFIG0_BIT6_DEFAULT; + + if (!adc->vref) { + tmp_reg |= MCP3564_CONFIG0_VREF_SET(1); + adc->vref_mv = MCP3564R_INT_VREF_MV; + } + + ret = mcp3564_write_8bits(adc, MCP3564_CONFIG0_REG, tmp_reg); + + adc->burnout_mode = MCP3564_CONFIG0_CS_SEL_0_0_uA; + + return ret; +} + +static IIO_DEVICE_ATTR(auto_zeroing_ref_enable, 0644, + mcp3564_auto_zeroing_ref_show, + mcp3564_auto_zeroing_ref_store, 0); + +static IIO_DEVICE_ATTR(auto_zeroing_mux_enable, 0644, + mcp3564_auto_zeroing_mux_show, + mcp3564_auto_zeroing_mux_store, 0); + +//#define MCP3564_DEV_ATTR(name) (&iio_dev_attr_##name.dev_attr.attr) + +static struct attribute *mcp3564_attributes[] = { + &iio_dev_attr_auto_zeroing_mux_enable.dev_attr.attr, + NULL +}; + +static struct attribute *mcp3564r_attributes[] = { + &iio_dev_attr_auto_zeroing_mux_enable.dev_attr.attr, + &iio_dev_attr_auto_zeroing_ref_enable.dev_attr.attr, + NULL +}; + +static struct attribute_group mcp3564_attribute_group = { + .attrs = mcp3564_attributes, +}; + +static struct attribute_group mcp3564r_attribute_group = { + .attrs = mcp3564r_attributes, +}; + +static const struct iio_info mcp3564_info = { + .read_raw = mcp3564_read_raw, + .read_avail = mcp3564_read_avail, + .write_raw = mcp3564_write_raw, + .write_raw_get_fmt = mcp3564_write_raw_get_fmt, + .read_label = mcp3564_read_label, + .attrs = &mcp3564_attribute_group, +}; + +static const struct iio_info mcp3564r_info = { + .read_raw = mcp3564_read_raw, + .read_avail = mcp3564_read_avail, + .write_raw = mcp3564_write_raw, + .write_raw_get_fmt = mcp3564_write_raw_get_fmt, + .read_label = mcp3564_read_label, + .attrs = &mcp3564r_attribute_group, +}; + +static int mcp3564_probe(struct spi_device *spi) +{ + int ret; + struct iio_dev *indio_dev; + struct mcp3564_state *adc; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc)); + if (!indio_dev) { + dev_err_probe(&indio_dev->dev, PTR_ERR(indio_dev), + "Can't allocate iio device\n"); + return -ENOMEM; + } + + adc = iio_priv(indio_dev); + adc->spi = spi; + + dev_dbg(&spi->dev, "%s: probe(spi = 0x%p)\n", __func__, spi); + + /* + * Do any chip specific initialization, e.g: + * read/write some registers + * enable/disable certain channels + * change the sampling rate to the requested value + */ + ret = mcp3564_config(indio_dev); + if (ret) { + return dev_err_probe(&spi->dev, ret, + "Can't configure MCP356X device\n"); + } + + dev_dbg(&spi->dev, "%s: Vref (mV): %d\n", __func__, adc->vref_mv); + + mcp3564_fill_scale_tbls(adc); + + indio_dev->name = adc->chip_info->name; + indio_dev->modes = INDIO_DIRECT_MODE; + + if (!adc->vref) + indio_dev->info = &mcp3564r_info; + else + indio_dev->info = &mcp3564_info; + + mutex_init(&adc->lock); + + ret = devm_iio_device_register(&spi->dev, indio_dev); + if (ret) { + return dev_err_probe(&spi->dev, ret, + "Can't register IIO device\n"); + } + + return 0; +} + +static const struct of_device_id mcp3564_dt_ids[] = { + { .compatible = "microchip,mcp3461", .data = &mcp3564_chip_infos_tbl[mcp3461] }, + { .compatible = "microchip,mcp3462", .data = &mcp3564_chip_infos_tbl[mcp3462] }, + { .compatible = "microchip,mcp3464", .data = &mcp3564_chip_infos_tbl[mcp3464] }, + { .compatible = "microchip,mcp3561", .data = &mcp3564_chip_infos_tbl[mcp3561] }, + { .compatible = "microchip,mcp3562", .data = &mcp3564_chip_infos_tbl[mcp3562] }, + { .compatible = "microchip,mcp3564", .data = &mcp3564_chip_infos_tbl[mcp3564] }, + { .compatible = "microchip,mcp3461r", .data = &mcp3564_chip_infos_tbl[mcp3461r] }, + { .compatible = "microchip,mcp3462r", .data = &mcp3564_chip_infos_tbl[mcp3462r] }, + { .compatible = "microchip,mcp3464r", .data = &mcp3564_chip_infos_tbl[mcp3464r] }, + { .compatible = "microchip,mcp3561r", .data = &mcp3564_chip_infos_tbl[mcp3561r] }, + { .compatible = "microchip,mcp3562r", .data = &mcp3564_chip_infos_tbl[mcp3562r] }, + { .compatible = "microchip,mcp3564r", .data = &mcp3564_chip_infos_tbl[mcp3564r] }, + { } +}; +MODULE_DEVICE_TABLE(of, mcp3564_dt_ids); + +static const struct spi_device_id mcp3564_id[] = { + { "mcp3461", (kernel_ulong_t)&mcp3564_chip_infos_tbl[mcp3461] }, + { "mcp3462", (kernel_ulong_t)&mcp3564_chip_infos_tbl[mcp3462] }, + { "mcp3464", (kernel_ulong_t)&mcp3564_chip_infos_tbl[mcp3464] }, + { "mcp3561", (kernel_ulong_t)&mcp3564_chip_infos_tbl[mcp3561] }, + { "mcp3562", (kernel_ulong_t)&mcp3564_chip_infos_tbl[mcp3562] }, + { "mcp3564", (kernel_ulong_t)&mcp3564_chip_infos_tbl[mcp3564] }, + { "mcp3461r", (kernel_ulong_t)&mcp3564_chip_infos_tbl[mcp3461r] }, + { "mcp3462r", (kernel_ulong_t)&mcp3564_chip_infos_tbl[mcp3462r] }, + { "mcp3464r", (kernel_ulong_t)&mcp3564_chip_infos_tbl[mcp3464r] }, + { "mcp3561r", (kernel_ulong_t)&mcp3564_chip_infos_tbl[mcp3561r] }, + { "mcp3562r", (kernel_ulong_t)&mcp3564_chip_infos_tbl[mcp3562r] }, + { "mcp3564r", (kernel_ulong_t)&mcp3564_chip_infos_tbl[mcp3564r] }, + { } +}; +MODULE_DEVICE_TABLE(spi, mcp3564_id); + +static struct spi_driver mcp3564_driver = { + .driver = { + .name = "mcp3564", + .of_match_table = mcp3564_dt_ids, + }, + .probe = mcp3564_probe, + .id_table = mcp3564_id, +}; + +module_spi_driver(mcp3564_driver); + +MODULE_AUTHOR("Marius Cristea <marius.cristea@xxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("Microchip MCP346x/MCP346xR and MCP356x/MCP346xR ADCs"); +MODULE_LICENSE("GPL v2"); -- 2.34.1
