aboutsummaryrefslogtreecommitdiff
path: root/drivers/iio/adc/qcom-spmi-iadc.c
diff options
context:
space:
mode:
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/qcom-spmi-iadc.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/qcom-spmi-iadc.c')
-rw-r--r--drivers/iio/adc/qcom-spmi-iadc.c585
1 files changed, 585 insertions, 0 deletions
diff --git a/drivers/iio/adc/qcom-spmi-iadc.c b/drivers/iio/adc/qcom-spmi-iadc.c
new file mode 100644
index 000000000..acbda6636
--- /dev/null
+++ b/drivers/iio/adc/qcom-spmi-iadc.c
@@ -0,0 +1,585 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2012-2014, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/bitops.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/iio/iio.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mutex.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+/* IADC register and bit definition */
+#define IADC_REVISION2 0x1
+#define IADC_REVISION2_SUPPORTED_IADC 1
+
+#define IADC_PERPH_TYPE 0x4
+#define IADC_PERPH_TYPE_ADC 8
+
+#define IADC_PERPH_SUBTYPE 0x5
+#define IADC_PERPH_SUBTYPE_IADC 3
+
+#define IADC_STATUS1 0x8
+#define IADC_STATUS1_OP_MODE 4
+#define IADC_STATUS1_REQ_STS BIT(1)
+#define IADC_STATUS1_EOC BIT(0)
+#define IADC_STATUS1_REQ_STS_EOC_MASK 0x3
+
+#define IADC_MODE_CTL 0x40
+#define IADC_OP_MODE_SHIFT 3
+#define IADC_OP_MODE_NORMAL 0
+#define IADC_TRIM_EN BIT(0)
+
+#define IADC_EN_CTL1 0x46
+#define IADC_EN_CTL1_SET BIT(7)
+
+#define IADC_CH_SEL_CTL 0x48
+
+#define IADC_DIG_PARAM 0x50
+#define IADC_DIG_DEC_RATIO_SEL_SHIFT 2
+
+#define IADC_HW_SETTLE_DELAY 0x51
+
+#define IADC_CONV_REQ 0x52
+#define IADC_CONV_REQ_SET BIT(7)
+
+#define IADC_FAST_AVG_CTL 0x5a
+#define IADC_FAST_AVG_EN 0x5b
+#define IADC_FAST_AVG_EN_SET BIT(7)
+
+#define IADC_PERH_RESET_CTL3 0xda
+#define IADC_FOLLOW_WARM_RB BIT(2)
+
+#define IADC_DATA 0x60 /* 16 bits */
+
+#define IADC_SEC_ACCESS 0xd0
+#define IADC_SEC_ACCESS_DATA 0xa5
+
+#define IADC_NOMINAL_RSENSE 0xf4
+#define IADC_NOMINAL_RSENSE_SIGN_MASK BIT(7)
+
+#define IADC_REF_GAIN_MICRO_VOLTS 17857
+
+#define IADC_INT_RSENSE_DEVIATION 15625 /* nano Ohms per bit */
+
+#define IADC_INT_RSENSE_IDEAL_VALUE 10000 /* micro Ohms */
+#define IADC_INT_RSENSE_DEFAULT_VALUE 7800 /* micro Ohms */
+#define IADC_INT_RSENSE_DEFAULT_GF 9000 /* micro Ohms */
+#define IADC_INT_RSENSE_DEFAULT_SMIC 9700 /* micro Ohms */
+
+#define IADC_CONV_TIME_MIN_US 2000
+#define IADC_CONV_TIME_MAX_US 2100
+
+#define IADC_DEF_PRESCALING 0 /* 1:1 */
+#define IADC_DEF_DECIMATION 0 /* 512 */
+#define IADC_DEF_HW_SETTLE_TIME 0 /* 0 us */
+#define IADC_DEF_AVG_SAMPLES 0 /* 1 sample */
+
+/* IADC channel list */
+#define IADC_INT_RSENSE 0
+#define IADC_EXT_RSENSE 1
+#define IADC_GAIN_17P857MV 3
+#define IADC_EXT_OFFSET_CSP_CSN 5
+#define IADC_INT_OFFSET_CSP2_CSN2 6
+
+/**
+ * struct iadc_chip - IADC Current ADC device structure.
+ * @regmap: regmap for register read/write.
+ * @dev: This device pointer.
+ * @base: base offset for the ADC peripheral.
+ * @rsense: Values of the internal and external sense resister in micro Ohms.
+ * @poll_eoc: Poll for end of conversion instead of waiting for IRQ.
+ * @offset: Raw offset values for the internal and external channels.
+ * @gain: Raw gain of the channels.
+ * @lock: ADC lock for access to the peripheral.
+ * @complete: ADC notification after end of conversion interrupt is received.
+ */
+struct iadc_chip {
+ struct regmap *regmap;
+ struct device *dev;
+ u16 base;
+ bool poll_eoc;
+ u32 rsense[2];
+ u16 offset[2];
+ u16 gain;
+ struct mutex lock;
+ struct completion complete;
+};
+
+static int iadc_read(struct iadc_chip *iadc, u16 offset, u8 *data)
+{
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(iadc->regmap, iadc->base + offset, &val);
+ if (ret < 0)
+ return ret;
+
+ *data = val;
+ return 0;
+}
+
+static int iadc_write(struct iadc_chip *iadc, u16 offset, u8 data)
+{
+ return regmap_write(iadc->regmap, iadc->base + offset, data);
+}
+
+static int iadc_reset(struct iadc_chip *iadc)
+{
+ u8 data;
+ int ret;
+
+ ret = iadc_write(iadc, IADC_SEC_ACCESS, IADC_SEC_ACCESS_DATA);
+ if (ret < 0)
+ return ret;
+
+ ret = iadc_read(iadc, IADC_PERH_RESET_CTL3, &data);
+ if (ret < 0)
+ return ret;
+
+ ret = iadc_write(iadc, IADC_SEC_ACCESS, IADC_SEC_ACCESS_DATA);
+ if (ret < 0)
+ return ret;
+
+ data |= IADC_FOLLOW_WARM_RB;
+
+ return iadc_write(iadc, IADC_PERH_RESET_CTL3, data);
+}
+
+static int iadc_set_state(struct iadc_chip *iadc, bool state)
+{
+ return iadc_write(iadc, IADC_EN_CTL1, state ? IADC_EN_CTL1_SET : 0);
+}
+
+static void iadc_status_show(struct iadc_chip *iadc)
+{
+ u8 mode, sta1, chan, dig, en, req;
+ int ret;
+
+ ret = iadc_read(iadc, IADC_MODE_CTL, &mode);
+ if (ret < 0)
+ return;
+
+ ret = iadc_read(iadc, IADC_DIG_PARAM, &dig);
+ if (ret < 0)
+ return;
+
+ ret = iadc_read(iadc, IADC_CH_SEL_CTL, &chan);
+ if (ret < 0)
+ return;
+
+ ret = iadc_read(iadc, IADC_CONV_REQ, &req);
+ if (ret < 0)
+ return;
+
+ ret = iadc_read(iadc, IADC_STATUS1, &sta1);
+ if (ret < 0)
+ return;
+
+ ret = iadc_read(iadc, IADC_EN_CTL1, &en);
+ if (ret < 0)
+ return;
+
+ dev_err(iadc->dev,
+ "mode:%02x en:%02x chan:%02x dig:%02x req:%02x sta1:%02x\n",
+ mode, en, chan, dig, req, sta1);
+}
+
+static int iadc_configure(struct iadc_chip *iadc, int channel)
+{
+ u8 decim, mode;
+ int ret;
+
+ /* Mode selection */
+ mode = (IADC_OP_MODE_NORMAL << IADC_OP_MODE_SHIFT) | IADC_TRIM_EN;
+ ret = iadc_write(iadc, IADC_MODE_CTL, mode);
+ if (ret < 0)
+ return ret;
+
+ /* Channel selection */
+ ret = iadc_write(iadc, IADC_CH_SEL_CTL, channel);
+ if (ret < 0)
+ return ret;
+
+ /* Digital parameter setup */
+ decim = IADC_DEF_DECIMATION << IADC_DIG_DEC_RATIO_SEL_SHIFT;
+ ret = iadc_write(iadc, IADC_DIG_PARAM, decim);
+ if (ret < 0)
+ return ret;
+
+ /* HW settle time delay */
+ ret = iadc_write(iadc, IADC_HW_SETTLE_DELAY, IADC_DEF_HW_SETTLE_TIME);
+ if (ret < 0)
+ return ret;
+
+ ret = iadc_write(iadc, IADC_FAST_AVG_CTL, IADC_DEF_AVG_SAMPLES);
+ if (ret < 0)
+ return ret;
+
+ if (IADC_DEF_AVG_SAMPLES)
+ ret = iadc_write(iadc, IADC_FAST_AVG_EN, IADC_FAST_AVG_EN_SET);
+ else
+ ret = iadc_write(iadc, IADC_FAST_AVG_EN, 0);
+
+ if (ret < 0)
+ return ret;
+
+ if (!iadc->poll_eoc)
+ reinit_completion(&iadc->complete);
+
+ ret = iadc_set_state(iadc, true);
+ if (ret < 0)
+ return ret;
+
+ /* Request conversion */
+ return iadc_write(iadc, IADC_CONV_REQ, IADC_CONV_REQ_SET);
+}
+
+static int iadc_poll_wait_eoc(struct iadc_chip *iadc, unsigned int interval_us)
+{
+ unsigned int count, retry;
+ int ret;
+ u8 sta1;
+
+ retry = interval_us / IADC_CONV_TIME_MIN_US;
+
+ for (count = 0; count < retry; count++) {
+ ret = iadc_read(iadc, IADC_STATUS1, &sta1);
+ if (ret < 0)
+ return ret;
+
+ sta1 &= IADC_STATUS1_REQ_STS_EOC_MASK;
+ if (sta1 == IADC_STATUS1_EOC)
+ return 0;
+
+ usleep_range(IADC_CONV_TIME_MIN_US, IADC_CONV_TIME_MAX_US);
+ }
+
+ iadc_status_show(iadc);
+
+ return -ETIMEDOUT;
+}
+
+static int iadc_read_result(struct iadc_chip *iadc, u16 *data)
+{
+ return regmap_bulk_read(iadc->regmap, iadc->base + IADC_DATA, data, 2);
+}
+
+static int iadc_do_conversion(struct iadc_chip *iadc, int chan, u16 *data)
+{
+ unsigned int wait;
+ int ret;
+
+ ret = iadc_configure(iadc, chan);
+ if (ret < 0)
+ goto exit;
+
+ wait = BIT(IADC_DEF_AVG_SAMPLES) * IADC_CONV_TIME_MIN_US * 2;
+
+ if (iadc->poll_eoc) {
+ ret = iadc_poll_wait_eoc(iadc, wait);
+ } else {
+ ret = wait_for_completion_timeout(&iadc->complete,
+ usecs_to_jiffies(wait));
+ if (!ret)
+ ret = -ETIMEDOUT;
+ else
+ /* double check conversion status */
+ ret = iadc_poll_wait_eoc(iadc, IADC_CONV_TIME_MIN_US);
+ }
+
+ if (!ret)
+ ret = iadc_read_result(iadc, data);
+exit:
+ iadc_set_state(iadc, false);
+ if (ret < 0)
+ dev_err(iadc->dev, "conversion failed\n");
+
+ return ret;
+}
+
+static int iadc_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct iadc_chip *iadc = iio_priv(indio_dev);
+ s32 isense_ua, vsense_uv;
+ u16 adc_raw, vsense_raw;
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ mutex_lock(&iadc->lock);
+ ret = iadc_do_conversion(iadc, chan->channel, &adc_raw);
+ mutex_unlock(&iadc->lock);
+ if (ret < 0)
+ return ret;
+
+ vsense_raw = adc_raw - iadc->offset[chan->channel];
+
+ vsense_uv = vsense_raw * IADC_REF_GAIN_MICRO_VOLTS;
+ vsense_uv /= (s32)iadc->gain - iadc->offset[chan->channel];
+
+ isense_ua = vsense_uv / iadc->rsense[chan->channel];
+
+ dev_dbg(iadc->dev, "off %d gain %d adc %d %duV I %duA\n",
+ iadc->offset[chan->channel], iadc->gain,
+ adc_raw, vsense_uv, isense_ua);
+
+ *val = isense_ua;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ *val = 0;
+ *val2 = 1000;
+ return IIO_VAL_INT_PLUS_MICRO;
+ }
+
+ return -EINVAL;
+}
+
+static const struct iio_info iadc_info = {
+ .read_raw = iadc_read_raw,
+};
+
+static irqreturn_t iadc_isr(int irq, void *dev_id)
+{
+ struct iadc_chip *iadc = dev_id;
+
+ complete(&iadc->complete);
+
+ return IRQ_HANDLED;
+}
+
+static int iadc_update_offset(struct iadc_chip *iadc)
+{
+ int ret;
+
+ ret = iadc_do_conversion(iadc, IADC_GAIN_17P857MV, &iadc->gain);
+ if (ret < 0)
+ return ret;
+
+ ret = iadc_do_conversion(iadc, IADC_INT_OFFSET_CSP2_CSN2,
+ &iadc->offset[IADC_INT_RSENSE]);
+ if (ret < 0)
+ return ret;
+
+ if (iadc->gain == iadc->offset[IADC_INT_RSENSE]) {
+ dev_err(iadc->dev, "error: internal offset == gain %d\n",
+ iadc->gain);
+ return -EINVAL;
+ }
+
+ ret = iadc_do_conversion(iadc, IADC_EXT_OFFSET_CSP_CSN,
+ &iadc->offset[IADC_EXT_RSENSE]);
+ if (ret < 0)
+ return ret;
+
+ if (iadc->gain == iadc->offset[IADC_EXT_RSENSE]) {
+ dev_err(iadc->dev, "error: external offset == gain %d\n",
+ iadc->gain);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int iadc_version_check(struct iadc_chip *iadc)
+{
+ u8 val;
+ int ret;
+
+ ret = iadc_read(iadc, IADC_PERPH_TYPE, &val);
+ if (ret < 0)
+ return ret;
+
+ if (val < IADC_PERPH_TYPE_ADC) {
+ dev_err(iadc->dev, "%d is not ADC\n", val);
+ return -EINVAL;
+ }
+
+ ret = iadc_read(iadc, IADC_PERPH_SUBTYPE, &val);
+ if (ret < 0)
+ return ret;
+
+ if (val < IADC_PERPH_SUBTYPE_IADC) {
+ dev_err(iadc->dev, "%d is not IADC\n", val);
+ return -EINVAL;
+ }
+
+ ret = iadc_read(iadc, IADC_REVISION2, &val);
+ if (ret < 0)
+ return ret;
+
+ if (val < IADC_REVISION2_SUPPORTED_IADC) {
+ dev_err(iadc->dev, "revision %d not supported\n", val);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int iadc_rsense_read(struct iadc_chip *iadc, struct device_node *node)
+{
+ int ret, sign, int_sense;
+ u8 deviation;
+
+ ret = of_property_read_u32(node, "qcom,external-resistor-micro-ohms",
+ &iadc->rsense[IADC_EXT_RSENSE]);
+ if (ret < 0)
+ iadc->rsense[IADC_EXT_RSENSE] = IADC_INT_RSENSE_IDEAL_VALUE;
+
+ if (!iadc->rsense[IADC_EXT_RSENSE]) {
+ dev_err(iadc->dev, "external resistor can't be zero Ohms");
+ return -EINVAL;
+ }
+
+ ret = iadc_read(iadc, IADC_NOMINAL_RSENSE, &deviation);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Deviation value stored is an offset from 10 mili Ohms, bit 7 is
+ * the sign, the remaining bits have an LSB of 15625 nano Ohms.
+ */
+ sign = (deviation & IADC_NOMINAL_RSENSE_SIGN_MASK) ? -1 : 1;
+
+ deviation &= ~IADC_NOMINAL_RSENSE_SIGN_MASK;
+
+ /* Scale it to nono Ohms */
+ int_sense = IADC_INT_RSENSE_IDEAL_VALUE * 1000;
+ int_sense += sign * deviation * IADC_INT_RSENSE_DEVIATION;
+ int_sense /= 1000; /* micro Ohms */
+
+ iadc->rsense[IADC_INT_RSENSE] = int_sense;
+ return 0;
+}
+
+static const struct iio_chan_spec iadc_channels[] = {
+ {
+ .type = IIO_CURRENT,
+ .datasheet_name = "INTERNAL_RSENSE",
+ .channel = 0,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ .indexed = 1,
+ },
+ {
+ .type = IIO_CURRENT,
+ .datasheet_name = "EXTERNAL_RSENSE",
+ .channel = 1,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ .indexed = 1,
+ },
+};
+
+static int iadc_probe(struct platform_device *pdev)
+{
+ struct device_node *node = pdev->dev.of_node;
+ struct device *dev = &pdev->dev;
+ struct iio_dev *indio_dev;
+ struct iadc_chip *iadc;
+ int ret, irq_eoc;
+ u32 res;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*iadc));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ iadc = iio_priv(indio_dev);
+ iadc->dev = dev;
+
+ iadc->regmap = dev_get_regmap(dev->parent, NULL);
+ if (!iadc->regmap)
+ return -ENODEV;
+
+ init_completion(&iadc->complete);
+ mutex_init(&iadc->lock);
+
+ ret = of_property_read_u32(node, "reg", &res);
+ if (ret < 0)
+ return -ENODEV;
+
+ iadc->base = res;
+
+ ret = iadc_version_check(iadc);
+ if (ret < 0)
+ return -ENODEV;
+
+ ret = iadc_rsense_read(iadc, node);
+ if (ret < 0)
+ return -ENODEV;
+
+ dev_dbg(iadc->dev, "sense resistors %d and %d micro Ohm\n",
+ iadc->rsense[IADC_INT_RSENSE],
+ iadc->rsense[IADC_EXT_RSENSE]);
+
+ irq_eoc = platform_get_irq(pdev, 0);
+ if (irq_eoc == -EPROBE_DEFER)
+ return irq_eoc;
+
+ if (irq_eoc < 0)
+ iadc->poll_eoc = true;
+
+ ret = iadc_reset(iadc);
+ if (ret < 0) {
+ dev_err(dev, "reset failed\n");
+ return ret;
+ }
+
+ if (!iadc->poll_eoc) {
+ ret = devm_request_irq(dev, irq_eoc, iadc_isr, 0,
+ "spmi-iadc", iadc);
+ if (!ret)
+ enable_irq_wake(irq_eoc);
+ else
+ return ret;
+ } else {
+ device_init_wakeup(iadc->dev, 1);
+ }
+
+ ret = iadc_update_offset(iadc);
+ if (ret < 0) {
+ dev_err(dev, "failed offset calibration\n");
+ return ret;
+ }
+
+ indio_dev->name = pdev->name;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->info = &iadc_info;
+ indio_dev->channels = iadc_channels;
+ indio_dev->num_channels = ARRAY_SIZE(iadc_channels);
+
+ return devm_iio_device_register(dev, indio_dev);
+}
+
+static const struct of_device_id iadc_match_table[] = {
+ { .compatible = "qcom,spmi-iadc" },
+ { }
+};
+
+MODULE_DEVICE_TABLE(of, iadc_match_table);
+
+static struct platform_driver iadc_driver = {
+ .driver = {
+ .name = "qcom-spmi-iadc",
+ .of_match_table = iadc_match_table,
+ },
+ .probe = iadc_probe,
+};
+
+module_platform_driver(iadc_driver);
+
+MODULE_ALIAS("platform:qcom-spmi-iadc");
+MODULE_DESCRIPTION("Qualcomm SPMI PMIC current ADC driver");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Ivan T. Ivanov <iivanov@mm-sol.com>");