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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/mcp320x.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 'drivers/iio/adc/mcp320x.c')
-rw-r--r--drivers/iio/adc/mcp320x.c530
1 files changed, 530 insertions, 0 deletions
diff --git a/drivers/iio/adc/mcp320x.c b/drivers/iio/adc/mcp320x.c
new file mode 100644
index 000000000..f3b81798b
--- /dev/null
+++ b/drivers/iio/adc/mcp320x.c
@@ -0,0 +1,530 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2013 Oskar Andero <oskar.andero@gmail.com>
+ * Copyright (C) 2014 Rose Technology
+ * Allan Bendorff Jensen <abj@rosetechnology.dk>
+ * Soren Andersen <san@rosetechnology.dk>
+ *
+ * Driver for following ADC chips from Microchip Technology's:
+ * 10 Bit converter
+ * MCP3001
+ * MCP3002
+ * MCP3004
+ * MCP3008
+ * ------------
+ * 12 bit converter
+ * MCP3201
+ * MCP3202
+ * MCP3204
+ * MCP3208
+ * ------------
+ * 13 bit converter
+ * MCP3301
+ * ------------
+ * 22 bit converter
+ * MCP3550
+ * MCP3551
+ * MCP3553
+ *
+ * Datasheet can be found here:
+ * https://ww1.microchip.com/downloads/en/DeviceDoc/21293C.pdf mcp3001
+ * https://ww1.microchip.com/downloads/en/DeviceDoc/21294E.pdf mcp3002
+ * https://ww1.microchip.com/downloads/en/DeviceDoc/21295d.pdf mcp3004/08
+ * http://ww1.microchip.com/downloads/en/DeviceDoc/21290D.pdf mcp3201
+ * http://ww1.microchip.com/downloads/en/DeviceDoc/21034D.pdf mcp3202
+ * http://ww1.microchip.com/downloads/en/DeviceDoc/21298c.pdf mcp3204/08
+ * https://ww1.microchip.com/downloads/en/DeviceDoc/21700E.pdf mcp3301
+ * http://ww1.microchip.com/downloads/en/DeviceDoc/21950D.pdf mcp3550/1/3
+ */
+
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/spi/spi.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/iio/iio.h>
+#include <linux/regulator/consumer.h>
+
+enum {
+ mcp3001,
+ mcp3002,
+ mcp3004,
+ mcp3008,
+ mcp3201,
+ mcp3202,
+ mcp3204,
+ mcp3208,
+ mcp3301,
+ mcp3550_50,
+ mcp3550_60,
+ mcp3551,
+ mcp3553,
+};
+
+struct mcp320x_chip_info {
+ const struct iio_chan_spec *channels;
+ unsigned int num_channels;
+ unsigned int resolution;
+ unsigned int conv_time; /* usec */
+};
+
+/**
+ * struct mcp320x - Microchip SPI ADC instance
+ * @spi: SPI slave (parent of the IIO device)
+ * @msg: SPI message to select a channel and receive a value from the ADC
+ * @transfer: SPI transfers used by @msg
+ * @start_conv_msg: SPI message to start a conversion by briefly asserting CS
+ * @start_conv_transfer: SPI transfer used by @start_conv_msg
+ * @reg: regulator generating Vref
+ * @lock: protects read sequences
+ * @chip_info: ADC properties
+ * @tx_buf: buffer for @transfer[0] (not used on single-channel converters)
+ * @rx_buf: buffer for @transfer[1]
+ */
+struct mcp320x {
+ struct spi_device *spi;
+ struct spi_message msg;
+ struct spi_transfer transfer[2];
+ struct spi_message start_conv_msg;
+ struct spi_transfer start_conv_transfer;
+
+ struct regulator *reg;
+ struct mutex lock;
+ const struct mcp320x_chip_info *chip_info;
+
+ u8 tx_buf __aligned(IIO_DMA_MINALIGN);
+ u8 rx_buf[4];
+};
+
+static int mcp320x_channel_to_tx_data(int device_index,
+ const unsigned int channel, bool differential)
+{
+ int start_bit = 1;
+
+ switch (device_index) {
+ case mcp3002:
+ case mcp3202:
+ return ((start_bit << 4) | (!differential << 3) |
+ (channel << 2));
+ case mcp3004:
+ case mcp3204:
+ case mcp3008:
+ case mcp3208:
+ return ((start_bit << 6) | (!differential << 5) |
+ (channel << 2));
+ default:
+ return -EINVAL;
+ }
+}
+
+static int mcp320x_adc_conversion(struct mcp320x *adc, u8 channel,
+ bool differential, int device_index, int *val)
+{
+ int ret;
+
+ if (adc->chip_info->conv_time) {
+ ret = spi_sync(adc->spi, &adc->start_conv_msg);
+ if (ret < 0)
+ return ret;
+
+ usleep_range(adc->chip_info->conv_time,
+ adc->chip_info->conv_time + 100);
+ }
+
+ memset(&adc->rx_buf, 0, sizeof(adc->rx_buf));
+ if (adc->chip_info->num_channels > 1)
+ adc->tx_buf = mcp320x_channel_to_tx_data(device_index, channel,
+ differential);
+
+ ret = spi_sync(adc->spi, &adc->msg);
+ if (ret < 0)
+ return ret;
+
+ switch (device_index) {
+ case mcp3001:
+ *val = (adc->rx_buf[0] << 5 | adc->rx_buf[1] >> 3);
+ return 0;
+ case mcp3002:
+ case mcp3004:
+ case mcp3008:
+ *val = (adc->rx_buf[0] << 2 | adc->rx_buf[1] >> 6);
+ return 0;
+ case mcp3201:
+ *val = (adc->rx_buf[0] << 7 | adc->rx_buf[1] >> 1);
+ return 0;
+ case mcp3202:
+ case mcp3204:
+ case mcp3208:
+ *val = (adc->rx_buf[0] << 4 | adc->rx_buf[1] >> 4);
+ return 0;
+ case mcp3301:
+ *val = sign_extend32((adc->rx_buf[0] & 0x1f) << 8
+ | adc->rx_buf[1], 12);
+ return 0;
+ case mcp3550_50:
+ case mcp3550_60:
+ case mcp3551:
+ case mcp3553: {
+ u32 raw = be32_to_cpup((__be32 *)adc->rx_buf);
+
+ if (!(adc->spi->mode & SPI_CPOL))
+ raw <<= 1; /* strip Data Ready bit in SPI mode 0,0 */
+
+ /*
+ * If the input is within -vref and vref, bit 21 is the sign.
+ * Up to 12% overrange or underrange are allowed, in which case
+ * bit 23 is the sign and bit 0 to 21 is the value.
+ */
+ raw >>= 8;
+ if (raw & BIT(22) && raw & BIT(23))
+ return -EIO; /* cannot have overrange AND underrange */
+ else if (raw & BIT(22))
+ raw &= ~BIT(22); /* overrange */
+ else if (raw & BIT(23) || raw & BIT(21))
+ raw |= GENMASK(31, 22); /* underrange or negative */
+
+ *val = (s32)raw;
+ return 0;
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+static int mcp320x_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *channel, int *val,
+ int *val2, long mask)
+{
+ struct mcp320x *adc = iio_priv(indio_dev);
+ int ret = -EINVAL;
+ int device_index = 0;
+
+ mutex_lock(&adc->lock);
+
+ device_index = spi_get_device_id(adc->spi)->driver_data;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = mcp320x_adc_conversion(adc, channel->address,
+ channel->differential, device_index, val);
+ if (ret < 0)
+ goto out;
+
+ ret = IIO_VAL_INT;
+ break;
+
+ case IIO_CHAN_INFO_SCALE:
+ ret = regulator_get_voltage(adc->reg);
+ if (ret < 0)
+ goto out;
+
+ /* convert regulator output voltage to mV */
+ *val = ret / 1000;
+ *val2 = adc->chip_info->resolution;
+ ret = IIO_VAL_FRACTIONAL_LOG2;
+ break;
+ }
+
+out:
+ mutex_unlock(&adc->lock);
+
+ return ret;
+}
+
+#define MCP320X_VOLTAGE_CHANNEL(num) \
+ { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .channel = (num), \
+ .address = (num), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \
+ }
+
+#define MCP320X_VOLTAGE_CHANNEL_DIFF(chan1, chan2) \
+ { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .channel = (chan1), \
+ .channel2 = (chan2), \
+ .address = (chan1), \
+ .differential = 1, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \
+ }
+
+static const struct iio_chan_spec mcp3201_channels[] = {
+ MCP320X_VOLTAGE_CHANNEL_DIFF(0, 1),
+};
+
+static const struct iio_chan_spec mcp3202_channels[] = {
+ MCP320X_VOLTAGE_CHANNEL(0),
+ MCP320X_VOLTAGE_CHANNEL(1),
+ MCP320X_VOLTAGE_CHANNEL_DIFF(0, 1),
+ MCP320X_VOLTAGE_CHANNEL_DIFF(1, 0),
+};
+
+static const struct iio_chan_spec mcp3204_channels[] = {
+ MCP320X_VOLTAGE_CHANNEL(0),
+ MCP320X_VOLTAGE_CHANNEL(1),
+ MCP320X_VOLTAGE_CHANNEL(2),
+ MCP320X_VOLTAGE_CHANNEL(3),
+ MCP320X_VOLTAGE_CHANNEL_DIFF(0, 1),
+ MCP320X_VOLTAGE_CHANNEL_DIFF(1, 0),
+ MCP320X_VOLTAGE_CHANNEL_DIFF(2, 3),
+ MCP320X_VOLTAGE_CHANNEL_DIFF(3, 2),
+};
+
+static const struct iio_chan_spec mcp3208_channels[] = {
+ MCP320X_VOLTAGE_CHANNEL(0),
+ MCP320X_VOLTAGE_CHANNEL(1),
+ MCP320X_VOLTAGE_CHANNEL(2),
+ MCP320X_VOLTAGE_CHANNEL(3),
+ MCP320X_VOLTAGE_CHANNEL(4),
+ MCP320X_VOLTAGE_CHANNEL(5),
+ MCP320X_VOLTAGE_CHANNEL(6),
+ MCP320X_VOLTAGE_CHANNEL(7),
+ MCP320X_VOLTAGE_CHANNEL_DIFF(0, 1),
+ MCP320X_VOLTAGE_CHANNEL_DIFF(1, 0),
+ MCP320X_VOLTAGE_CHANNEL_DIFF(2, 3),
+ MCP320X_VOLTAGE_CHANNEL_DIFF(3, 2),
+ MCP320X_VOLTAGE_CHANNEL_DIFF(4, 5),
+ MCP320X_VOLTAGE_CHANNEL_DIFF(5, 4),
+ MCP320X_VOLTAGE_CHANNEL_DIFF(6, 7),
+ MCP320X_VOLTAGE_CHANNEL_DIFF(7, 6),
+};
+
+static const struct iio_info mcp320x_info = {
+ .read_raw = mcp320x_read_raw,
+};
+
+static const struct mcp320x_chip_info mcp320x_chip_infos[] = {
+ [mcp3001] = {
+ .channels = mcp3201_channels,
+ .num_channels = ARRAY_SIZE(mcp3201_channels),
+ .resolution = 10
+ },
+ [mcp3002] = {
+ .channels = mcp3202_channels,
+ .num_channels = ARRAY_SIZE(mcp3202_channels),
+ .resolution = 10
+ },
+ [mcp3004] = {
+ .channels = mcp3204_channels,
+ .num_channels = ARRAY_SIZE(mcp3204_channels),
+ .resolution = 10
+ },
+ [mcp3008] = {
+ .channels = mcp3208_channels,
+ .num_channels = ARRAY_SIZE(mcp3208_channels),
+ .resolution = 10
+ },
+ [mcp3201] = {
+ .channels = mcp3201_channels,
+ .num_channels = ARRAY_SIZE(mcp3201_channels),
+ .resolution = 12
+ },
+ [mcp3202] = {
+ .channels = mcp3202_channels,
+ .num_channels = ARRAY_SIZE(mcp3202_channels),
+ .resolution = 12
+ },
+ [mcp3204] = {
+ .channels = mcp3204_channels,
+ .num_channels = ARRAY_SIZE(mcp3204_channels),
+ .resolution = 12
+ },
+ [mcp3208] = {
+ .channels = mcp3208_channels,
+ .num_channels = ARRAY_SIZE(mcp3208_channels),
+ .resolution = 12
+ },
+ [mcp3301] = {
+ .channels = mcp3201_channels,
+ .num_channels = ARRAY_SIZE(mcp3201_channels),
+ .resolution = 13
+ },
+ [mcp3550_50] = {
+ .channels = mcp3201_channels,
+ .num_channels = ARRAY_SIZE(mcp3201_channels),
+ .resolution = 21,
+ /* 2% max deviation + 144 clock periods to exit shutdown */
+ .conv_time = 80000 * 1.02 + 144000 / 102.4,
+ },
+ [mcp3550_60] = {
+ .channels = mcp3201_channels,
+ .num_channels = ARRAY_SIZE(mcp3201_channels),
+ .resolution = 21,
+ .conv_time = 66670 * 1.02 + 144000 / 122.88,
+ },
+ [mcp3551] = {
+ .channels = mcp3201_channels,
+ .num_channels = ARRAY_SIZE(mcp3201_channels),
+ .resolution = 21,
+ .conv_time = 73100 * 1.02 + 144000 / 112.64,
+ },
+ [mcp3553] = {
+ .channels = mcp3201_channels,
+ .num_channels = ARRAY_SIZE(mcp3201_channels),
+ .resolution = 21,
+ .conv_time = 16670 * 1.02 + 144000 / 122.88,
+ },
+};
+
+static int mcp320x_probe(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev;
+ struct mcp320x *adc;
+ const struct mcp320x_chip_info *chip_info;
+ int ret, device_index;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ adc = iio_priv(indio_dev);
+ adc->spi = spi;
+
+ indio_dev->name = spi_get_device_id(spi)->name;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->info = &mcp320x_info;
+ spi_set_drvdata(spi, indio_dev);
+
+ device_index = spi_get_device_id(spi)->driver_data;
+ chip_info = &mcp320x_chip_infos[device_index];
+ indio_dev->channels = chip_info->channels;
+ indio_dev->num_channels = chip_info->num_channels;
+
+ adc->chip_info = chip_info;
+
+ adc->transfer[0].tx_buf = &adc->tx_buf;
+ adc->transfer[0].len = sizeof(adc->tx_buf);
+ adc->transfer[1].rx_buf = adc->rx_buf;
+ adc->transfer[1].len = DIV_ROUND_UP(chip_info->resolution, 8);
+
+ if (chip_info->num_channels == 1)
+ /* single-channel converters are rx only (no MOSI pin) */
+ spi_message_init_with_transfers(&adc->msg,
+ &adc->transfer[1], 1);
+ else
+ spi_message_init_with_transfers(&adc->msg, adc->transfer,
+ ARRAY_SIZE(adc->transfer));
+
+ switch (device_index) {
+ case mcp3550_50:
+ case mcp3550_60:
+ case mcp3551:
+ case mcp3553:
+ /* rx len increases from 24 to 25 bit in SPI mode 0,0 */
+ if (!(spi->mode & SPI_CPOL))
+ adc->transfer[1].len++;
+
+ /* conversions are started by asserting CS pin for 8 usec */
+ adc->start_conv_transfer.delay.value = 8;
+ adc->start_conv_transfer.delay.unit = SPI_DELAY_UNIT_USECS;
+ spi_message_init_with_transfers(&adc->start_conv_msg,
+ &adc->start_conv_transfer, 1);
+
+ /*
+ * If CS was previously kept low (continuous conversion mode)
+ * and then changed to high, the chip is in shutdown.
+ * Sometimes it fails to wake from shutdown and clocks out
+ * only 0xffffff. The magic sequence of performing two
+ * conversions without delay between them resets the chip
+ * and ensures all subsequent conversions succeed.
+ */
+ mcp320x_adc_conversion(adc, 0, 1, device_index, &ret);
+ mcp320x_adc_conversion(adc, 0, 1, device_index, &ret);
+ }
+
+ adc->reg = devm_regulator_get(&spi->dev, "vref");
+ if (IS_ERR(adc->reg))
+ return PTR_ERR(adc->reg);
+
+ ret = regulator_enable(adc->reg);
+ if (ret < 0)
+ return ret;
+
+ mutex_init(&adc->lock);
+
+ ret = iio_device_register(indio_dev);
+ if (ret < 0)
+ goto reg_disable;
+
+ return 0;
+
+reg_disable:
+ regulator_disable(adc->reg);
+
+ return ret;
+}
+
+static void mcp320x_remove(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev = spi_get_drvdata(spi);
+ struct mcp320x *adc = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+ regulator_disable(adc->reg);
+}
+
+static const struct of_device_id mcp320x_dt_ids[] = {
+ /* NOTE: The use of compatibles with no vendor prefix is deprecated. */
+ { .compatible = "mcp3001" },
+ { .compatible = "mcp3002" },
+ { .compatible = "mcp3004" },
+ { .compatible = "mcp3008" },
+ { .compatible = "mcp3201" },
+ { .compatible = "mcp3202" },
+ { .compatible = "mcp3204" },
+ { .compatible = "mcp3208" },
+ { .compatible = "mcp3301" },
+ { .compatible = "microchip,mcp3001" },
+ { .compatible = "microchip,mcp3002" },
+ { .compatible = "microchip,mcp3004" },
+ { .compatible = "microchip,mcp3008" },
+ { .compatible = "microchip,mcp3201" },
+ { .compatible = "microchip,mcp3202" },
+ { .compatible = "microchip,mcp3204" },
+ { .compatible = "microchip,mcp3208" },
+ { .compatible = "microchip,mcp3301" },
+ { .compatible = "microchip,mcp3550-50" },
+ { .compatible = "microchip,mcp3550-60" },
+ { .compatible = "microchip,mcp3551" },
+ { .compatible = "microchip,mcp3553" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, mcp320x_dt_ids);
+
+static const struct spi_device_id mcp320x_id[] = {
+ { "mcp3001", mcp3001 },
+ { "mcp3002", mcp3002 },
+ { "mcp3004", mcp3004 },
+ { "mcp3008", mcp3008 },
+ { "mcp3201", mcp3201 },
+ { "mcp3202", mcp3202 },
+ { "mcp3204", mcp3204 },
+ { "mcp3208", mcp3208 },
+ { "mcp3301", mcp3301 },
+ { "mcp3550-50", mcp3550_50 },
+ { "mcp3550-60", mcp3550_60 },
+ { "mcp3551", mcp3551 },
+ { "mcp3553", mcp3553 },
+ { }
+};
+MODULE_DEVICE_TABLE(spi, mcp320x_id);
+
+static struct spi_driver mcp320x_driver = {
+ .driver = {
+ .name = "mcp320x",
+ .of_match_table = mcp320x_dt_ids,
+ },
+ .probe = mcp320x_probe,
+ .remove = mcp320x_remove,
+ .id_table = mcp320x_id,
+};
+module_spi_driver(mcp320x_driver);
+
+MODULE_AUTHOR("Oskar Andero <oskar.andero@gmail.com>");
+MODULE_DESCRIPTION("Microchip Technology MCP3x01/02/04/08 and MCP3550/1/3");
+MODULE_LICENSE("GPL v2");