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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/nau7802.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 '')
-rw-r--r-- | drivers/iio/adc/nau7802.c | 560 |
1 files changed, 560 insertions, 0 deletions
diff --git a/drivers/iio/adc/nau7802.c b/drivers/iio/adc/nau7802.c new file mode 100644 index 000000000..c1261ecd4 --- /dev/null +++ b/drivers/iio/adc/nau7802.c @@ -0,0 +1,560 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for the Nuvoton NAU7802 ADC + * + * Copyright 2013 Free Electrons + */ + +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/property.h> +#include <linux/wait.h> +#include <linux/log2.h> + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> + +#define NAU7802_REG_PUCTRL 0x00 +#define NAU7802_PUCTRL_RR(x) (x << 0) +#define NAU7802_PUCTRL_RR_BIT NAU7802_PUCTRL_RR(1) +#define NAU7802_PUCTRL_PUD(x) (x << 1) +#define NAU7802_PUCTRL_PUD_BIT NAU7802_PUCTRL_PUD(1) +#define NAU7802_PUCTRL_PUA(x) (x << 2) +#define NAU7802_PUCTRL_PUA_BIT NAU7802_PUCTRL_PUA(1) +#define NAU7802_PUCTRL_PUR(x) (x << 3) +#define NAU7802_PUCTRL_PUR_BIT NAU7802_PUCTRL_PUR(1) +#define NAU7802_PUCTRL_CS(x) (x << 4) +#define NAU7802_PUCTRL_CS_BIT NAU7802_PUCTRL_CS(1) +#define NAU7802_PUCTRL_CR(x) (x << 5) +#define NAU7802_PUCTRL_CR_BIT NAU7802_PUCTRL_CR(1) +#define NAU7802_PUCTRL_AVDDS(x) (x << 7) +#define NAU7802_PUCTRL_AVDDS_BIT NAU7802_PUCTRL_AVDDS(1) +#define NAU7802_REG_CTRL1 0x01 +#define NAU7802_CTRL1_VLDO(x) (x << 3) +#define NAU7802_CTRL1_GAINS(x) (x) +#define NAU7802_CTRL1_GAINS_BITS 0x07 +#define NAU7802_REG_CTRL2 0x02 +#define NAU7802_CTRL2_CHS(x) (x << 7) +#define NAU7802_CTRL2_CRS(x) (x << 4) +#define NAU7802_SAMP_FREQ_320 0x07 +#define NAU7802_CTRL2_CHS_BIT NAU7802_CTRL2_CHS(1) +#define NAU7802_REG_ADC_B2 0x12 +#define NAU7802_REG_ADC_B1 0x13 +#define NAU7802_REG_ADC_B0 0x14 +#define NAU7802_REG_ADC_CTRL 0x15 + +#define NAU7802_MIN_CONVERSIONS 6 + +struct nau7802_state { + struct i2c_client *client; + s32 last_value; + struct mutex lock; + struct mutex data_lock; + u32 vref_mv; + u32 conversion_count; + u32 min_conversions; + u8 sample_rate; + u32 scale_avail[8]; + struct completion value_ok; +}; + +#define NAU7802_CHANNEL(chan) { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .channel = (chan), \ + .scan_index = (chan), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_SAMP_FREQ) \ +} + +static const struct iio_chan_spec nau7802_chan_array[] = { + NAU7802_CHANNEL(0), + NAU7802_CHANNEL(1), +}; + +static const u16 nau7802_sample_freq_avail[] = {10, 20, 40, 80, + 10, 10, 10, 320}; + +static ssize_t nau7802_show_scales(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct nau7802_state *st = iio_priv(dev_to_iio_dev(dev)); + int i, len = 0; + + for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) + len += scnprintf(buf + len, PAGE_SIZE - len, "0.%09d ", + st->scale_avail[i]); + + buf[len-1] = '\n'; + + return len; +} + +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("10 40 80 320"); + +static IIO_DEVICE_ATTR(in_voltage_scale_available, S_IRUGO, nau7802_show_scales, + NULL, 0); + +static struct attribute *nau7802_attributes[] = { + &iio_const_attr_sampling_frequency_available.dev_attr.attr, + &iio_dev_attr_in_voltage_scale_available.dev_attr.attr, + NULL +}; + +static const struct attribute_group nau7802_attribute_group = { + .attrs = nau7802_attributes, +}; + +static int nau7802_set_gain(struct nau7802_state *st, int gain) +{ + int ret; + + mutex_lock(&st->lock); + st->conversion_count = 0; + + ret = i2c_smbus_read_byte_data(st->client, NAU7802_REG_CTRL1); + if (ret < 0) + goto nau7802_sysfs_set_gain_out; + ret = i2c_smbus_write_byte_data(st->client, NAU7802_REG_CTRL1, + (ret & (~NAU7802_CTRL1_GAINS_BITS)) | + gain); + +nau7802_sysfs_set_gain_out: + mutex_unlock(&st->lock); + + return ret; +} + +static int nau7802_read_conversion(struct nau7802_state *st) +{ + int data; + + mutex_lock(&st->data_lock); + data = i2c_smbus_read_byte_data(st->client, NAU7802_REG_ADC_B2); + if (data < 0) + goto nau7802_read_conversion_out; + st->last_value = data << 16; + + data = i2c_smbus_read_byte_data(st->client, NAU7802_REG_ADC_B1); + if (data < 0) + goto nau7802_read_conversion_out; + st->last_value |= data << 8; + + data = i2c_smbus_read_byte_data(st->client, NAU7802_REG_ADC_B0); + if (data < 0) + goto nau7802_read_conversion_out; + st->last_value |= data; + + st->last_value = sign_extend32(st->last_value, 23); + +nau7802_read_conversion_out: + mutex_unlock(&st->data_lock); + + return data; +} + +/* + * Conversions are synchronised on the rising edge of NAU7802_PUCTRL_CS_BIT + */ +static int nau7802_sync(struct nau7802_state *st) +{ + int ret; + + ret = i2c_smbus_read_byte_data(st->client, NAU7802_REG_PUCTRL); + if (ret < 0) + return ret; + ret = i2c_smbus_write_byte_data(st->client, NAU7802_REG_PUCTRL, + ret | NAU7802_PUCTRL_CS_BIT); + + return ret; +} + +static irqreturn_t nau7802_eoc_trigger(int irq, void *private) +{ + struct iio_dev *indio_dev = private; + struct nau7802_state *st = iio_priv(indio_dev); + int status; + + status = i2c_smbus_read_byte_data(st->client, NAU7802_REG_PUCTRL); + if (status < 0) + return IRQ_HANDLED; + + if (!(status & NAU7802_PUCTRL_CR_BIT)) + return IRQ_NONE; + + if (nau7802_read_conversion(st) < 0) + return IRQ_HANDLED; + + /* + * Because there is actually only one ADC for both channels, we have to + * wait for enough conversions to happen before getting a significant + * value when changing channels and the values are far apart. + */ + if (st->conversion_count < NAU7802_MIN_CONVERSIONS) + st->conversion_count++; + if (st->conversion_count >= NAU7802_MIN_CONVERSIONS) + complete(&st->value_ok); + + return IRQ_HANDLED; +} + +static int nau7802_read_irq(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val) +{ + struct nau7802_state *st = iio_priv(indio_dev); + int ret; + + reinit_completion(&st->value_ok); + enable_irq(st->client->irq); + + nau7802_sync(st); + + /* read registers to ensure we flush everything */ + ret = nau7802_read_conversion(st); + if (ret < 0) + goto read_chan_info_failure; + + /* Wait for a conversion to finish */ + ret = wait_for_completion_interruptible_timeout(&st->value_ok, + msecs_to_jiffies(1000)); + if (ret == 0) + ret = -ETIMEDOUT; + + if (ret < 0) + goto read_chan_info_failure; + + disable_irq(st->client->irq); + + *val = st->last_value; + + return IIO_VAL_INT; + +read_chan_info_failure: + disable_irq(st->client->irq); + + return ret; +} + +static int nau7802_read_poll(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val) +{ + struct nau7802_state *st = iio_priv(indio_dev); + int ret; + + nau7802_sync(st); + + /* read registers to ensure we flush everything */ + ret = nau7802_read_conversion(st); + if (ret < 0) + return ret; + + /* + * Because there is actually only one ADC for both channels, we have to + * wait for enough conversions to happen before getting a significant + * value when changing channels and the values are far appart. + */ + do { + ret = i2c_smbus_read_byte_data(st->client, NAU7802_REG_PUCTRL); + if (ret < 0) + return ret; + + while (!(ret & NAU7802_PUCTRL_CR_BIT)) { + if (st->sample_rate != NAU7802_SAMP_FREQ_320) + msleep(20); + else + mdelay(4); + ret = i2c_smbus_read_byte_data(st->client, + NAU7802_REG_PUCTRL); + if (ret < 0) + return ret; + } + + ret = nau7802_read_conversion(st); + if (ret < 0) + return ret; + if (st->conversion_count < NAU7802_MIN_CONVERSIONS) + st->conversion_count++; + } while (st->conversion_count < NAU7802_MIN_CONVERSIONS); + + *val = st->last_value; + + return IIO_VAL_INT; +} + +static int nau7802_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct nau7802_state *st = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&st->lock); + /* + * Select the channel to use + * - Channel 1 is value 0 in the CHS register + * - Channel 2 is value 1 in the CHS register + */ + ret = i2c_smbus_read_byte_data(st->client, NAU7802_REG_CTRL2); + if (ret < 0) { + mutex_unlock(&st->lock); + return ret; + } + + if (((ret & NAU7802_CTRL2_CHS_BIT) && !chan->channel) || + (!(ret & NAU7802_CTRL2_CHS_BIT) && + chan->channel)) { + st->conversion_count = 0; + ret = i2c_smbus_write_byte_data(st->client, + NAU7802_REG_CTRL2, + NAU7802_CTRL2_CHS(chan->channel) | + NAU7802_CTRL2_CRS(st->sample_rate)); + + if (ret < 0) { + mutex_unlock(&st->lock); + return ret; + } + } + + if (st->client->irq) + ret = nau7802_read_irq(indio_dev, chan, val); + else + ret = nau7802_read_poll(indio_dev, chan, val); + + mutex_unlock(&st->lock); + return ret; + + case IIO_CHAN_INFO_SCALE: + ret = i2c_smbus_read_byte_data(st->client, NAU7802_REG_CTRL1); + if (ret < 0) + return ret; + + /* + * We have 24 bits of signed data, that means 23 bits of data + * plus the sign bit + */ + *val = st->vref_mv; + *val2 = 23 + (ret & NAU7802_CTRL1_GAINS_BITS); + + return IIO_VAL_FRACTIONAL_LOG2; + + case IIO_CHAN_INFO_SAMP_FREQ: + *val = nau7802_sample_freq_avail[st->sample_rate]; + *val2 = 0; + return IIO_VAL_INT; + + default: + break; + } + + return -EINVAL; +} + +static int nau7802_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct nau7802_state *st = iio_priv(indio_dev); + int i, ret; + + switch (mask) { + case IIO_CHAN_INFO_SCALE: + for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) + if (val2 == st->scale_avail[i]) + return nau7802_set_gain(st, i); + + break; + + case IIO_CHAN_INFO_SAMP_FREQ: + for (i = 0; i < ARRAY_SIZE(nau7802_sample_freq_avail); i++) + if (val == nau7802_sample_freq_avail[i]) { + mutex_lock(&st->lock); + st->sample_rate = i; + st->conversion_count = 0; + ret = i2c_smbus_write_byte_data(st->client, + NAU7802_REG_CTRL2, + NAU7802_CTRL2_CRS(st->sample_rate)); + mutex_unlock(&st->lock); + return ret; + } + + break; + + default: + break; + } + + return -EINVAL; +} + +static int nau7802_write_raw_get_fmt(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + long mask) +{ + return IIO_VAL_INT_PLUS_NANO; +} + +static const struct iio_info nau7802_info = { + .read_raw = &nau7802_read_raw, + .write_raw = &nau7802_write_raw, + .write_raw_get_fmt = nau7802_write_raw_get_fmt, + .attrs = &nau7802_attribute_group, +}; + +static int nau7802_probe(struct i2c_client *client) +{ + struct iio_dev *indio_dev; + struct nau7802_state *st; + int i, ret; + u8 data; + u32 tmp = 0; + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st)); + if (indio_dev == NULL) + return -ENOMEM; + + st = iio_priv(indio_dev); + + indio_dev->name = dev_name(&client->dev); + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->info = &nau7802_info; + + st->client = client; + + /* Reset the device */ + ret = i2c_smbus_write_byte_data(st->client, NAU7802_REG_PUCTRL, + NAU7802_PUCTRL_RR_BIT); + if (ret < 0) + return ret; + + /* Enter normal operation mode */ + ret = i2c_smbus_write_byte_data(st->client, NAU7802_REG_PUCTRL, + NAU7802_PUCTRL_PUD_BIT); + if (ret < 0) + return ret; + + /* + * After about 200 usecs, the device should be ready and then + * the Power Up bit will be set to 1. If not, wait for it. + */ + udelay(210); + ret = i2c_smbus_read_byte_data(st->client, NAU7802_REG_PUCTRL); + if (ret < 0) + return ret; + if (!(ret & NAU7802_PUCTRL_PUR_BIT)) + return ret; + + device_property_read_u32(&client->dev, "nuvoton,vldo", &tmp); + st->vref_mv = tmp; + + data = NAU7802_PUCTRL_PUD_BIT | NAU7802_PUCTRL_PUA_BIT | + NAU7802_PUCTRL_CS_BIT; + if (tmp >= 2400) + data |= NAU7802_PUCTRL_AVDDS_BIT; + + ret = i2c_smbus_write_byte_data(st->client, NAU7802_REG_PUCTRL, data); + if (ret < 0) + return ret; + ret = i2c_smbus_write_byte_data(st->client, NAU7802_REG_ADC_CTRL, 0x30); + if (ret < 0) + return ret; + + if (tmp >= 2400) { + data = NAU7802_CTRL1_VLDO((4500 - tmp) / 300); + ret = i2c_smbus_write_byte_data(st->client, NAU7802_REG_CTRL1, + data); + if (ret < 0) + return ret; + } + + /* Populate available ADC input ranges */ + for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) + st->scale_avail[i] = (((u64)st->vref_mv) * 1000000000ULL) + >> (23 + i); + + init_completion(&st->value_ok); + + /* + * The ADC fires continuously and we can't do anything about + * it. So we need to have the IRQ disabled by default, and we + * will enable them back when we will need them.. + */ + if (client->irq) { + ret = devm_request_threaded_irq(&client->dev, client->irq, + NULL, + nau7802_eoc_trigger, + IRQF_TRIGGER_HIGH | IRQF_ONESHOT | + IRQF_NO_AUTOEN, + client->dev.driver->name, + indio_dev); + if (ret) { + /* + * What may happen here is that our IRQ controller is + * not able to get level interrupt but this is required + * by this ADC as when going over 40 sample per second, + * the interrupt line may stay high between conversions. + * So, we continue no matter what but we switch to + * polling mode. + */ + dev_info(&client->dev, + "Failed to allocate IRQ, using polling mode\n"); + client->irq = 0; + } + } + + if (!client->irq) { + /* + * We are polling, use the fastest sample rate by + * default + */ + st->sample_rate = NAU7802_SAMP_FREQ_320; + ret = i2c_smbus_write_byte_data(st->client, NAU7802_REG_CTRL2, + NAU7802_CTRL2_CRS(st->sample_rate)); + if (ret) + return ret; + } + + /* Setup the ADC channels available on the board */ + indio_dev->num_channels = ARRAY_SIZE(nau7802_chan_array); + indio_dev->channels = nau7802_chan_array; + + mutex_init(&st->lock); + mutex_init(&st->data_lock); + + return devm_iio_device_register(&client->dev, indio_dev); +} + +static const struct i2c_device_id nau7802_i2c_id[] = { + { "nau7802", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, nau7802_i2c_id); + +static const struct of_device_id nau7802_dt_ids[] = { + { .compatible = "nuvoton,nau7802" }, + {}, +}; +MODULE_DEVICE_TABLE(of, nau7802_dt_ids); + +static struct i2c_driver nau7802_driver = { + .probe_new = nau7802_probe, + .id_table = nau7802_i2c_id, + .driver = { + .name = "nau7802", + .of_match_table = nau7802_dt_ids, + }, +}; + +module_i2c_driver(nau7802_driver); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Nuvoton NAU7802 ADC Driver"); +MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); +MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@free-electrons.com>"); |