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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/iio/adc/max9611.c | |
download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip |
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski:
"Core:
- Add dedicated kmem_cache for typical/small skb->head, avoid having
to access struct page at kfree time, and improve memory use.
- Introduce sysctl to set default RPS configuration for new netdevs.
- Define Netlink protocol specification format which can be used to
describe messages used by each family and auto-generate parsers.
Add tools for generating kernel data structures and uAPI headers.
- Expose all net/core sysctls inside netns.
- Remove 4s sleep in netpoll if carrier is instantly detected on
boot.
- Add configurable limit of MDB entries per port, and port-vlan.
- Continue populating drop reasons throughout the stack.
- Retire a handful of legacy Qdiscs and classifiers.
Protocols:
- Support IPv4 big TCP (TSO frames larger than 64kB).
- Add IP_LOCAL_PORT_RANGE socket option, to control local port range
on socket by socket basis.
- Track and report in procfs number of MPTCP sockets used.
- Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
manager.
- IPv6: don't check net.ipv6.route.max_size and rely on garbage
collection to free memory (similarly to IPv4).
- Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).
- ICMP: add per-rate limit counters.
- Add support for user scanning requests in ieee802154.
- Remove static WEP support.
- Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
reporting.
- WiFi 7 EHT channel puncturing support (client & AP).
BPF:
- Add a rbtree data structure following the "next-gen data structure"
precedent set by recently added linked list, that is, by using
kfunc + kptr instead of adding a new BPF map type.
- Expose XDP hints via kfuncs with initial support for RX hash and
timestamp metadata.
- Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
better support decap on GRE tunnel devices not operating in collect
metadata.
- Improve x86 JIT's codegen for PROBE_MEM runtime error checks.
- Remove the need for trace_printk_lock for bpf_trace_printk and
bpf_trace_vprintk helpers.
- Extend libbpf's bpf_tracing.h support for tracing arguments of
kprobes/uprobes and syscall as a special case.
- Significantly reduce the search time for module symbols by
livepatch and BPF.
- Enable cpumasks to be used as kptrs, which is useful for tracing
programs tracking which tasks end up running on which CPUs in
different time intervals.
- Add support for BPF trampoline on s390x and riscv64.
- Add capability to export the XDP features supported by the NIC.
- Add __bpf_kfunc tag for marking kernel functions as kfuncs.
- Add cgroup.memory=nobpf kernel parameter option to disable BPF
memory accounting for container environments.
Netfilter:
- Remove the CLUSTERIP target. It has been marked as obsolete for
years, and we still have WARN splats wrt races of the out-of-band
/proc interface installed by this target.
- Add 'destroy' commands to nf_tables. They are identical to the
existing 'delete' commands, but do not return an error if the
referenced object (set, chain, rule...) did not exist.
Driver API:
- Improve cpumask_local_spread() locality to help NICs set the right
IRQ affinity on AMD platforms.
- Separate C22 and C45 MDIO bus transactions more clearly.
- Introduce new DCB table to control DSCP rewrite on egress.
- Support configuration of Physical Layer Collision Avoidance (PLCA)
Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
shared medium Ethernet.
- Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
preemption of low priority frames by high priority frames.
- Add support for controlling MACSec offload using netlink SET.
- Rework devlink instance refcounts to allow registration and
de-registration under the instance lock. Split the code into
multiple files, drop some of the unnecessarily granular locks and
factor out common parts of netlink operation handling.
- Add TX frame aggregation parameters (for USB drivers).
- Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
messages with notifications for debug.
- Allow offloading of UDP NEW connections via act_ct.
- Add support for per action HW stats in TC.
- Support hardware miss to TC action (continue processing in SW from
a specific point in the action chain).
- Warn if old Wireless Extension user space interface is used with
modern cfg80211/mac80211 drivers. Do not support Wireless
Extensions for Wi-Fi 7 devices at all. Everyone should switch to
using nl80211 interface instead.
- Improve the CAN bit timing configuration. Use extack to return
error messages directly to user space, update the SJW handling,
including the definition of a new default value that will benefit
CAN-FD controllers, by increasing their oscillator tolerance.
New hardware / drivers:
- Ethernet:
- nVidia BlueField-3 support (control traffic driver)
- Ethernet support for imx93 SoCs
- Motorcomm yt8531 gigabit Ethernet PHY
- onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
- Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
- Amlogic gxl MDIO mux
- WiFi:
- RealTek RTL8188EU (rtl8xxxu)
- Qualcomm Wi-Fi 7 devices (ath12k)
- CAN:
- Renesas R-Car V4H
Drivers:
- Bluetooth:
- Set Per Platform Antenna Gain (PPAG) for Intel controllers.
- Ethernet NICs:
- Intel (1G, igc):
- support TSN / Qbv / packet scheduling features of i226 model
- Intel (100G, ice):
- use GNSS subsystem instead of TTY
- multi-buffer XDP support
- extend support for GPIO pins to E823 devices
- nVidia/Mellanox:
- update the shared buffer configuration on PFC commands
- implement PTP adjphase function for HW offset control
- TC support for Geneve and GRE with VF tunnel offload
- more efficient crypto key management method
- multi-port eswitch support
- Netronome/Corigine:
- add DCB IEEE support
- support IPsec offloading for NFP3800
- Freescale/NXP (enetc):
- support XDP_REDIRECT for XDP non-linear buffers
- improve reconfig, avoid link flap and waiting for idle
- support MAC Merge layer
- Other NICs:
- sfc/ef100: add basic devlink support for ef100
- ionic: rx_push mode operation (writing descriptors via MMIO)
- bnxt: use the auxiliary bus abstraction for RDMA
- r8169: disable ASPM and reset bus in case of tx timeout
- cpsw: support QSGMII mode for J721e CPSW9G
- cpts: support pulse-per-second output
- ngbe: add an mdio bus driver
- usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
- r8152: handle devices with FW with NCM support
- amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
- virtio-net: support multi buffer XDP
- virtio/vsock: replace virtio_vsock_pkt with sk_buff
- tsnep: XDP support
- Ethernet high-speed switches:
- nVidia/Mellanox (mlxsw):
- add support for latency TLV (in FW control messages)
- Microchip (sparx5):
- separate explicit and implicit traffic forwarding rules, make
the implicit rules always active
- add support for egress DSCP rewrite
- IS0 VCAP support (Ingress Classification)
- IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
etc.)
- ES2 VCAP support (Egress Access Control)
- support for Per-Stream Filtering and Policing (802.1Q,
8.6.5.1)
- Ethernet embedded switches:
- Marvell (mv88e6xxx):
- add MAB (port auth) offload support
- enable PTP receive for mv88e6390
- NXP (ocelot):
- support MAC Merge layer
- support for the the vsc7512 internal copper phys
- Microchip:
- lan9303: convert to PHYLINK
- lan966x: support TC flower filter statistics
- lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
- lan937x: support Credit Based Shaper configuration
- ksz9477: support Energy Efficient Ethernet
- other:
- qca8k: convert to regmap read/write API, use bulk operations
- rswitch: Improve TX timestamp accuracy
- Intel WiFi (iwlwifi):
- EHT (Wi-Fi 7) rate reporting
- STEP equalizer support: transfer some STEP (connection to radio
on platforms with integrated wifi) related parameters from the
BIOS to the firmware.
- Qualcomm 802.11ax WiFi (ath11k):
- IPQ5018 support
- Fine Timing Measurement (FTM) responder role support
- channel 177 support
- MediaTek WiFi (mt76):
- per-PHY LED support
- mt7996: EHT (Wi-Fi 7) support
- Wireless Ethernet Dispatch (WED) reset support
- switch to using page pool allocator
- RealTek WiFi (rtw89):
- support new version of Bluetooth co-existance
- Mobile:
- rmnet: support TX aggregation"
* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
page_pool: add a comment explaining the fragment counter usage
net: ethtool: fix __ethtool_dev_mm_supported() implementation
ethtool: pse-pd: Fix double word in comments
xsk: add linux/vmalloc.h to xsk.c
sefltests: netdevsim: wait for devlink instance after netns removal
selftest: fib_tests: Always cleanup before exit
net/mlx5e: Align IPsec ASO result memory to be as required by hardware
net/mlx5e: TC, Set CT miss to the specific ct action instance
net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
net/mlx5: Refactor tc miss handling to a single function
net/mlx5: Kconfig: Make tc offload depend on tc skb extension
net/sched: flower: Support hardware miss to tc action
net/sched: flower: Move filter handle initialization earlier
net/sched: cls_api: Support hardware miss to tc action
net/sched: Rename user cookie and act cookie
sfc: fix builds without CONFIG_RTC_LIB
sfc: clean up some inconsistent indentings
net/mlx4_en: Introduce flexible array to silence overflow warning
net: lan966x: Fix possible deadlock inside PTP
net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
...
Diffstat (limited to 'drivers/iio/adc/max9611.c')
-rw-r--r-- | drivers/iio/adc/max9611.c | 565 |
1 files changed, 565 insertions, 0 deletions
diff --git a/drivers/iio/adc/max9611.c b/drivers/iio/adc/max9611.c new file mode 100644 index 000000000..cb7f47854 --- /dev/null +++ b/drivers/iio/adc/max9611.c @@ -0,0 +1,565 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * iio/adc/max9611.c + * + * Maxim max9611/max9612 high side current sense amplifier with + * 12-bit ADC interface. + * + * Copyright (C) 2017 Jacopo Mondi + */ + +/* + * This driver supports input common-mode voltage, current-sense + * amplifier with programmable gains and die temperature reading from + * Maxim max9611/max9612. + * + * Op-amp, analog comparator, and watchdog functionalities are not + * supported by this driver. + */ + +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/property.h> + +#define DRIVER_NAME "max9611" + +/* max9611 register addresses */ +#define MAX9611_REG_CSA_DATA 0x00 +#define MAX9611_REG_RS_DATA 0x02 +#define MAX9611_REG_TEMP_DATA 0x08 +#define MAX9611_REG_CTRL1 0x0a +#define MAX9611_REG_CTRL2 0x0b + +/* max9611 REG1 mux configuration options */ +#define MAX9611_MUX_MASK GENMASK(3, 0) +#define MAX9611_MUX_SENSE_1x 0x00 +#define MAX9611_MUX_SENSE_4x 0x01 +#define MAX9611_MUX_SENSE_8x 0x02 +#define MAX9611_INPUT_VOLT 0x03 +#define MAX9611_MUX_TEMP 0x06 + +/* max9611 voltage (both csa and input) helper macros */ +#define MAX9611_VOLTAGE_SHIFT 0x04 +#define MAX9611_VOLTAGE_RAW(_r) ((_r) >> MAX9611_VOLTAGE_SHIFT) + +/* + * max9611 current sense amplifier voltage output: + * LSB and offset values depends on selected gain (1x, 4x, 8x) + * + * GAIN LSB (nV) OFFSET (LSB steps) + * 1x 107500 1 + * 4x 26880 1 + * 8x 13440 3 + * + * The complete formula to calculate current sense voltage is: + * (((adc_read >> 4) - offset) / ((1 / LSB) * 10^-3) + */ +#define MAX9611_CSA_1X_LSB_nV 107500 +#define MAX9611_CSA_4X_LSB_nV 26880 +#define MAX9611_CSA_8X_LSB_nV 13440 + +#define MAX9611_CSA_1X_OFFS_RAW 1 +#define MAX9611_CSA_4X_OFFS_RAW 1 +#define MAX9611_CSA_8X_OFFS_RAW 3 + +/* + * max9611 common input mode (CIM): LSB is 14mV, with 14mV offset at 25 C + * + * The complete formula to calculate input common voltage is: + * (((adc_read >> 4) * 1000) - offset) / (1 / 14 * 1000) + */ +#define MAX9611_CIM_LSB_mV 14 +#define MAX9611_CIM_OFFSET_RAW 1 + +/* + * max9611 temperature reading: LSB is 480 milli degrees Celsius + * + * The complete formula to calculate temperature is: + * ((adc_read >> 7) * 1000) / (1 / 480 * 1000) + */ +#define MAX9611_TEMP_MAX_POS 0x7f80 +#define MAX9611_TEMP_MAX_NEG 0xff80 +#define MAX9611_TEMP_MIN_NEG 0xd980 +#define MAX9611_TEMP_MASK GENMASK(15, 7) +#define MAX9611_TEMP_SHIFT 0x07 +#define MAX9611_TEMP_RAW(_r) ((_r) >> MAX9611_TEMP_SHIFT) +#define MAX9611_TEMP_SCALE_NUM 1000000 +#define MAX9611_TEMP_SCALE_DIV 2083 + +/* + * Conversion time is 2 ms (typically) at Ta=25 degreeC + * No maximum value is known, so play it safe. + */ +#define MAX9611_CONV_TIME_US_RANGE 3000, 3300 + +struct max9611_dev { + struct device *dev; + struct i2c_client *i2c_client; + struct mutex lock; + unsigned int shunt_resistor_uohm; +}; + +enum max9611_conf_ids { + CONF_SENSE_1x, + CONF_SENSE_4x, + CONF_SENSE_8x, + CONF_IN_VOLT, + CONF_TEMP, +}; + +/* + * max9611_mux_conf - associate ADC mux configuration with register address + * where data shall be read from + */ +static const unsigned int max9611_mux_conf[][2] = { + [CONF_SENSE_1x] = { MAX9611_MUX_SENSE_1x, MAX9611_REG_CSA_DATA }, + [CONF_SENSE_4x] = { MAX9611_MUX_SENSE_4x, MAX9611_REG_CSA_DATA }, + [CONF_SENSE_8x] = { MAX9611_MUX_SENSE_8x, MAX9611_REG_CSA_DATA }, + [CONF_IN_VOLT] = { MAX9611_INPUT_VOLT, MAX9611_REG_RS_DATA }, + [CONF_TEMP] = { MAX9611_MUX_TEMP, MAX9611_REG_TEMP_DATA }, +}; + +enum max9611_csa_gain { + CSA_GAIN_1x = CONF_SENSE_1x, + CSA_GAIN_4x = CONF_SENSE_4x, + CSA_GAIN_8x = CONF_SENSE_8x, +}; + +enum max9611_csa_gain_params { + CSA_GAIN_LSB_nV, + CSA_GAIN_OFFS_RAW, +}; + +/* + * max9611_csa_gain_conf - associate gain multiplier with LSB and + * offset values. + * + * Group together parameters associated with configurable gain + * on current sense amplifier path to ADC interface. + * Current sense read routine adjusts gain until it gets a meaningful + * value; use this structure to retrieve the correct LSB and offset values. + */ +static const unsigned int max9611_gain_conf[][2] = { + [CSA_GAIN_1x] = { MAX9611_CSA_1X_LSB_nV, MAX9611_CSA_1X_OFFS_RAW, }, + [CSA_GAIN_4x] = { MAX9611_CSA_4X_LSB_nV, MAX9611_CSA_4X_OFFS_RAW, }, + [CSA_GAIN_8x] = { MAX9611_CSA_8X_LSB_nV, MAX9611_CSA_8X_OFFS_RAW, }, +}; + +enum max9611_chan_addrs { + MAX9611_CHAN_VOLTAGE_INPUT, + MAX9611_CHAN_VOLTAGE_SENSE, + MAX9611_CHAN_TEMPERATURE, + MAX9611_CHAN_CURRENT_LOAD, + MAX9611_CHAN_POWER_LOAD, +}; + +static const struct iio_chan_spec max9611_channels[] = { + { + .type = IIO_TEMP, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE), + .address = MAX9611_CHAN_TEMPERATURE, + }, + { + .type = IIO_VOLTAGE, + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), + .address = MAX9611_CHAN_VOLTAGE_SENSE, + .indexed = 1, + .channel = 0, + }, + { + .type = IIO_VOLTAGE, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_OFFSET), + .address = MAX9611_CHAN_VOLTAGE_INPUT, + .indexed = 1, + .channel = 1, + }, + { + .type = IIO_CURRENT, + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), + .address = MAX9611_CHAN_CURRENT_LOAD, + }, + { + .type = IIO_POWER, + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), + .address = MAX9611_CHAN_POWER_LOAD + }, +}; + +/** + * max9611_read_single() - read a single value from ADC interface + * + * Data registers are 16 bit long, spread between two 8 bit registers + * with consecutive addresses. + * Configure ADC mux first, then read register at address "reg_addr". + * The smbus_read_word routine asks for 16 bits and the ADC is kind enough + * to return values from "reg_addr" and "reg_addr + 1" consecutively. + * Data are transmitted with big-endian ordering: MSB arrives first. + * + * @max9611: max9611 device + * @selector: index for mux and register configuration + * @raw_val: the value returned from ADC + */ +static int max9611_read_single(struct max9611_dev *max9611, + enum max9611_conf_ids selector, + u16 *raw_val) +{ + int ret; + + u8 mux_conf = max9611_mux_conf[selector][0] & MAX9611_MUX_MASK; + u8 reg_addr = max9611_mux_conf[selector][1]; + + /* + * Keep mutex lock held during read-write to avoid mux register + * (CTRL1) re-configuration. + */ + mutex_lock(&max9611->lock); + ret = i2c_smbus_write_byte_data(max9611->i2c_client, + MAX9611_REG_CTRL1, mux_conf); + if (ret) { + dev_err(max9611->dev, "i2c write byte failed: 0x%2x - 0x%2x\n", + MAX9611_REG_CTRL1, mux_conf); + mutex_unlock(&max9611->lock); + return ret; + } + + /* need a delay here to make register configuration stabilize. */ + + usleep_range(MAX9611_CONV_TIME_US_RANGE); + + ret = i2c_smbus_read_word_swapped(max9611->i2c_client, reg_addr); + if (ret < 0) { + dev_err(max9611->dev, "i2c read word from 0x%2x failed\n", + reg_addr); + mutex_unlock(&max9611->lock); + return ret; + } + + *raw_val = ret; + mutex_unlock(&max9611->lock); + + return 0; +} + +/** + * max9611_read_csa_voltage() - read current sense amplifier output voltage + * + * Current sense amplifier output voltage is read through a configurable + * 1x, 4x or 8x gain. + * Start with plain 1x gain, and adjust gain control properly until a + * meaningful value is read from ADC output. + * + * @max9611: max9611 device + * @adc_raw: raw value read from ADC output + * @csa_gain: gain configuration option selector + */ +static int max9611_read_csa_voltage(struct max9611_dev *max9611, + u16 *adc_raw, + enum max9611_csa_gain *csa_gain) +{ + enum max9611_conf_ids gain_selectors[] = { + CONF_SENSE_1x, + CONF_SENSE_4x, + CONF_SENSE_8x + }; + unsigned int i; + int ret; + + for (i = 0; i < ARRAY_SIZE(gain_selectors); ++i) { + ret = max9611_read_single(max9611, gain_selectors[i], adc_raw); + if (ret) + return ret; + + if (*adc_raw > 0) { + *csa_gain = (enum max9611_csa_gain)gain_selectors[i]; + return 0; + } + } + + return -EIO; +} + +static int max9611_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct max9611_dev *dev = iio_priv(indio_dev); + enum max9611_csa_gain gain_selector; + const unsigned int *csa_gain; + u16 adc_data; + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + + switch (chan->address) { + case MAX9611_CHAN_TEMPERATURE: + ret = max9611_read_single(dev, CONF_TEMP, + &adc_data); + if (ret) + return -EINVAL; + + *val = MAX9611_TEMP_RAW(adc_data); + return IIO_VAL_INT; + + case MAX9611_CHAN_VOLTAGE_INPUT: + ret = max9611_read_single(dev, CONF_IN_VOLT, + &adc_data); + if (ret) + return -EINVAL; + + *val = MAX9611_VOLTAGE_RAW(adc_data); + return IIO_VAL_INT; + } + + break; + + case IIO_CHAN_INFO_OFFSET: + /* MAX9611_CHAN_VOLTAGE_INPUT */ + *val = MAX9611_CIM_OFFSET_RAW; + + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + + switch (chan->address) { + case MAX9611_CHAN_TEMPERATURE: + *val = MAX9611_TEMP_SCALE_NUM; + *val2 = MAX9611_TEMP_SCALE_DIV; + + return IIO_VAL_FRACTIONAL; + + case MAX9611_CHAN_VOLTAGE_INPUT: + *val = MAX9611_CIM_LSB_mV; + + return IIO_VAL_INT; + } + + break; + + case IIO_CHAN_INFO_PROCESSED: + + switch (chan->address) { + case MAX9611_CHAN_VOLTAGE_SENSE: + /* + * processed (mV): (raw - offset) * LSB (nV) / 10^6 + * + * Even if max9611 can output raw csa voltage readings, + * use a produced value as scale depends on gain. + */ + ret = max9611_read_csa_voltage(dev, &adc_data, + &gain_selector); + if (ret) + return -EINVAL; + + csa_gain = max9611_gain_conf[gain_selector]; + + adc_data -= csa_gain[CSA_GAIN_OFFS_RAW]; + *val = MAX9611_VOLTAGE_RAW(adc_data) * + csa_gain[CSA_GAIN_LSB_nV]; + *val2 = 1000000; + + return IIO_VAL_FRACTIONAL; + + case MAX9611_CHAN_CURRENT_LOAD: + /* processed (mA): Vcsa (nV) / Rshunt (uOhm) */ + ret = max9611_read_csa_voltage(dev, &adc_data, + &gain_selector); + if (ret) + return -EINVAL; + + csa_gain = max9611_gain_conf[gain_selector]; + + adc_data -= csa_gain[CSA_GAIN_OFFS_RAW]; + *val = MAX9611_VOLTAGE_RAW(adc_data) * + csa_gain[CSA_GAIN_LSB_nV]; + *val2 = dev->shunt_resistor_uohm; + + return IIO_VAL_FRACTIONAL; + + case MAX9611_CHAN_POWER_LOAD: + /* + * processed (mW): Vin (mV) * Vcsa (uV) / + * Rshunt (uOhm) + */ + ret = max9611_read_single(dev, CONF_IN_VOLT, + &adc_data); + if (ret) + return -EINVAL; + + adc_data -= MAX9611_CIM_OFFSET_RAW; + *val = MAX9611_VOLTAGE_RAW(adc_data) * + MAX9611_CIM_LSB_mV; + + ret = max9611_read_csa_voltage(dev, &adc_data, + &gain_selector); + if (ret) + return -EINVAL; + + csa_gain = max9611_gain_conf[gain_selector]; + + /* divide by 10^3 here to avoid 32bit overflow */ + adc_data -= csa_gain[CSA_GAIN_OFFS_RAW]; + *val *= MAX9611_VOLTAGE_RAW(adc_data) * + csa_gain[CSA_GAIN_LSB_nV] / 1000; + *val2 = dev->shunt_resistor_uohm; + + return IIO_VAL_FRACTIONAL; + } + + break; + } + + return -EINVAL; +} + +static ssize_t max9611_shunt_resistor_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct max9611_dev *max9611 = iio_priv(dev_to_iio_dev(dev)); + unsigned int i, r; + + i = max9611->shunt_resistor_uohm / 1000000; + r = max9611->shunt_resistor_uohm % 1000000; + + return sysfs_emit(buf, "%u.%06u\n", i, r); +} + +static IIO_DEVICE_ATTR(in_power_shunt_resistor, 0444, + max9611_shunt_resistor_show, NULL, 0); +static IIO_DEVICE_ATTR(in_current_shunt_resistor, 0444, + max9611_shunt_resistor_show, NULL, 0); + +static struct attribute *max9611_attributes[] = { + &iio_dev_attr_in_power_shunt_resistor.dev_attr.attr, + &iio_dev_attr_in_current_shunt_resistor.dev_attr.attr, + NULL, +}; + +static const struct attribute_group max9611_attribute_group = { + .attrs = max9611_attributes, +}; + +static const struct iio_info indio_info = { + .read_raw = max9611_read_raw, + .attrs = &max9611_attribute_group, +}; + +static int max9611_init(struct max9611_dev *max9611) +{ + struct i2c_client *client = max9611->i2c_client; + u16 regval; + int ret; + + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_WRITE_BYTE | + I2C_FUNC_SMBUS_READ_WORD_DATA)) { + dev_err(max9611->dev, + "I2c adapter does not support smbus write_byte or read_word functionalities: aborting probe.\n"); + return -EINVAL; + } + + /* Make sure die temperature is in range to test communications. */ + ret = max9611_read_single(max9611, CONF_TEMP, ®val); + if (ret) + return ret; + + regval &= MAX9611_TEMP_MASK; + + if ((regval > MAX9611_TEMP_MAX_POS && + regval < MAX9611_TEMP_MIN_NEG) || + regval > MAX9611_TEMP_MAX_NEG) { + dev_err(max9611->dev, + "Invalid value received from ADC 0x%4x: aborting\n", + regval); + return -EIO; + } + + /* Mux shall be zeroed back before applying other configurations */ + ret = i2c_smbus_write_byte_data(max9611->i2c_client, + MAX9611_REG_CTRL1, 0); + if (ret) { + dev_err(max9611->dev, "i2c write byte failed: 0x%2x - 0x%2x\n", + MAX9611_REG_CTRL1, 0); + return ret; + } + + ret = i2c_smbus_write_byte_data(max9611->i2c_client, + MAX9611_REG_CTRL2, 0); + if (ret) { + dev_err(max9611->dev, "i2c write byte failed: 0x%2x - 0x%2x\n", + MAX9611_REG_CTRL2, 0); + return ret; + } + usleep_range(MAX9611_CONV_TIME_US_RANGE); + + return 0; +} + +static const struct of_device_id max9611_of_table[] = { + {.compatible = "maxim,max9611", .data = "max9611"}, + {.compatible = "maxim,max9612", .data = "max9612"}, + { }, +}; + +MODULE_DEVICE_TABLE(of, max9611_of_table); +static int max9611_probe(struct i2c_client *client) +{ + const char * const shunt_res_prop = "shunt-resistor-micro-ohms"; + struct max9611_dev *max9611; + struct iio_dev *indio_dev; + struct device *dev = &client->dev; + unsigned int of_shunt; + int ret; + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*max9611)); + if (!indio_dev) + return -ENOMEM; + + i2c_set_clientdata(client, indio_dev); + + max9611 = iio_priv(indio_dev); + max9611->dev = dev; + max9611->i2c_client = client; + mutex_init(&max9611->lock); + + ret = device_property_read_u32(dev, shunt_res_prop, &of_shunt); + if (ret) { + dev_err(dev, "Missing %s property for %pfw node\n", + shunt_res_prop, dev_fwnode(dev)); + return ret; + } + max9611->shunt_resistor_uohm = of_shunt; + + ret = max9611_init(max9611); + if (ret) + return ret; + + indio_dev->name = device_get_match_data(dev); + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->info = &indio_info; + indio_dev->channels = max9611_channels; + indio_dev->num_channels = ARRAY_SIZE(max9611_channels); + + return devm_iio_device_register(dev, indio_dev); +} + +static struct i2c_driver max9611_driver = { + .driver = { + .name = DRIVER_NAME, + .of_match_table = max9611_of_table, + }, + .probe_new = max9611_probe, +}; +module_i2c_driver(max9611_driver); + +MODULE_AUTHOR("Jacopo Mondi <jacopo+renesas@jmondi.org>"); +MODULE_DESCRIPTION("Maxim max9611/12 current sense amplifier with 12bit ADC"); +MODULE_LICENSE("GPL v2"); |