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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/iio/adc/nau7802.c
downloadlinux-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.c560
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>");