aboutsummaryrefslogtreecommitdiff
path: root/drivers/w1/slaves/w1_ds2438.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/w1/slaves/w1_ds2438.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/w1/slaves/w1_ds2438.c')
-rw-r--r--drivers/w1/slaves/w1_ds2438.c518
1 files changed, 518 insertions, 0 deletions
diff --git a/drivers/w1/slaves/w1_ds2438.c b/drivers/w1/slaves/w1_ds2438.c
new file mode 100644
index 000000000..ca64f99c8
--- /dev/null
+++ b/drivers/w1/slaves/w1_ds2438.c
@@ -0,0 +1,518 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 1-Wire implementation for the ds2438 chip
+ *
+ * Copyright (c) 2017 Mariusz Bialonczyk <manio@skyboo.net>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+
+#include <linux/w1.h>
+
+#define W1_FAMILY_DS2438 0x26
+
+#define W1_DS2438_RETRIES 3
+
+/* Memory commands */
+#define W1_DS2438_READ_SCRATCH 0xBE
+#define W1_DS2438_WRITE_SCRATCH 0x4E
+#define W1_DS2438_COPY_SCRATCH 0x48
+#define W1_DS2438_RECALL_MEMORY 0xB8
+/* Register commands */
+#define W1_DS2438_CONVERT_TEMP 0x44
+#define W1_DS2438_CONVERT_VOLTAGE 0xB4
+
+#define DS2438_PAGE_SIZE 8
+#define DS2438_ADC_INPUT_VAD 0
+#define DS2438_ADC_INPUT_VDD 1
+#define DS2438_MAX_CONVERSION_TIME 10 /* ms */
+
+/* Page #0 definitions */
+#define DS2438_STATUS_REG 0x00 /* Status/Configuration Register */
+#define DS2438_STATUS_IAD (1 << 0) /* Current A/D Control Bit */
+#define DS2438_STATUS_CA (1 << 1) /* Current Accumulator Configuration */
+#define DS2438_STATUS_EE (1 << 2) /* Current Accumulator Shadow Selector bit */
+#define DS2438_STATUS_AD (1 << 3) /* Voltage A/D Input Select Bit */
+#define DS2438_STATUS_TB (1 << 4) /* Temperature Busy Flag */
+#define DS2438_STATUS_NVB (1 << 5) /* Nonvolatile Memory Busy Flag */
+#define DS2438_STATUS_ADB (1 << 6) /* A/D Converter Busy Flag */
+
+#define DS2438_TEMP_LSB 0x01
+#define DS2438_TEMP_MSB 0x02
+#define DS2438_VOLTAGE_LSB 0x03
+#define DS2438_VOLTAGE_MSB 0x04
+#define DS2438_CURRENT_LSB 0x05
+#define DS2438_CURRENT_MSB 0x06
+#define DS2438_THRESHOLD 0x07
+
+/* Page #1 definitions */
+#define DS2438_ETM_0 0x00
+#define DS2438_ETM_1 0x01
+#define DS2438_ETM_2 0x02
+#define DS2438_ETM_3 0x03
+#define DS2438_ICA 0x04
+#define DS2438_OFFSET_LSB 0x05
+#define DS2438_OFFSET_MSB 0x06
+
+static int w1_ds2438_get_page(struct w1_slave *sl, int pageno, u8 *buf)
+{
+ unsigned int retries = W1_DS2438_RETRIES;
+ u8 w1_buf[2];
+ u8 crc;
+ size_t count;
+
+ while (retries--) {
+ crc = 0;
+
+ if (w1_reset_select_slave(sl))
+ continue;
+ w1_buf[0] = W1_DS2438_RECALL_MEMORY;
+ w1_buf[1] = (u8)pageno;
+ w1_write_block(sl->master, w1_buf, 2);
+
+ if (w1_reset_select_slave(sl))
+ continue;
+ w1_buf[0] = W1_DS2438_READ_SCRATCH;
+ w1_buf[1] = (u8)pageno;
+ w1_write_block(sl->master, w1_buf, 2);
+
+ count = w1_read_block(sl->master, buf, DS2438_PAGE_SIZE + 1);
+ if (count == DS2438_PAGE_SIZE + 1) {
+ crc = w1_calc_crc8(buf, DS2438_PAGE_SIZE);
+
+ /* check for correct CRC */
+ if ((u8)buf[DS2438_PAGE_SIZE] == crc)
+ return 0;
+ }
+ }
+ return -1;
+}
+
+static int w1_ds2438_get_temperature(struct w1_slave *sl, int16_t *temperature)
+{
+ unsigned int retries = W1_DS2438_RETRIES;
+ u8 w1_buf[DS2438_PAGE_SIZE + 1 /*for CRC*/];
+ unsigned int tm = DS2438_MAX_CONVERSION_TIME;
+ unsigned long sleep_rem;
+ int ret;
+
+ mutex_lock(&sl->master->bus_mutex);
+
+ while (retries--) {
+ if (w1_reset_select_slave(sl))
+ continue;
+ w1_write_8(sl->master, W1_DS2438_CONVERT_TEMP);
+
+ mutex_unlock(&sl->master->bus_mutex);
+ sleep_rem = msleep_interruptible(tm);
+ if (sleep_rem != 0) {
+ ret = -1;
+ goto post_unlock;
+ }
+
+ if (mutex_lock_interruptible(&sl->master->bus_mutex) != 0) {
+ ret = -1;
+ goto post_unlock;
+ }
+
+ break;
+ }
+
+ if (w1_ds2438_get_page(sl, 0, w1_buf) == 0) {
+ *temperature = (((int16_t) w1_buf[DS2438_TEMP_MSB]) << 8) | ((uint16_t) w1_buf[DS2438_TEMP_LSB]);
+ ret = 0;
+ } else
+ ret = -1;
+
+ mutex_unlock(&sl->master->bus_mutex);
+
+post_unlock:
+ return ret;
+}
+
+static int w1_ds2438_change_config_bit(struct w1_slave *sl, u8 mask, u8 value)
+{
+ unsigned int retries = W1_DS2438_RETRIES;
+ u8 w1_buf[3];
+ u8 status;
+ int perform_write = 0;
+
+ while (retries--) {
+ if (w1_reset_select_slave(sl))
+ continue;
+ w1_buf[0] = W1_DS2438_RECALL_MEMORY;
+ w1_buf[1] = 0x00;
+ w1_write_block(sl->master, w1_buf, 2);
+
+ if (w1_reset_select_slave(sl))
+ continue;
+ w1_buf[0] = W1_DS2438_READ_SCRATCH;
+ w1_buf[1] = 0x00;
+ w1_write_block(sl->master, w1_buf, 2);
+
+ /* reading one byte of result */
+ status = w1_read_8(sl->master);
+
+ /* if bit0=1, set a value to a mask for easy compare */
+ if (value)
+ value = mask;
+
+ if ((status & mask) == value)
+ return 0; /* already set as requested */
+
+ /* changing bit */
+ status ^= mask;
+ perform_write = 1;
+
+ break;
+ }
+
+ if (perform_write) {
+ retries = W1_DS2438_RETRIES;
+ while (retries--) {
+ if (w1_reset_select_slave(sl))
+ continue;
+ w1_buf[0] = W1_DS2438_WRITE_SCRATCH;
+ w1_buf[1] = 0x00;
+ w1_buf[2] = status;
+ w1_write_block(sl->master, w1_buf, 3);
+
+ if (w1_reset_select_slave(sl))
+ continue;
+ w1_buf[0] = W1_DS2438_COPY_SCRATCH;
+ w1_buf[1] = 0x00;
+ w1_write_block(sl->master, w1_buf, 2);
+
+ return 0;
+ }
+ }
+ return -1;
+}
+
+static int w1_ds2438_change_offset_register(struct w1_slave *sl, u8 *value)
+{
+ unsigned int retries = W1_DS2438_RETRIES;
+ u8 w1_buf[9];
+ u8 w1_page1_buf[DS2438_PAGE_SIZE + 1 /*for CRC*/];
+
+ if (w1_ds2438_get_page(sl, 1, w1_page1_buf) == 0) {
+ memcpy(&w1_buf[2], w1_page1_buf, DS2438_PAGE_SIZE - 1); /* last register reserved */
+ w1_buf[7] = value[0]; /* change only offset register */
+ w1_buf[8] = value[1];
+ while (retries--) {
+ if (w1_reset_select_slave(sl))
+ continue;
+ w1_buf[0] = W1_DS2438_WRITE_SCRATCH;
+ w1_buf[1] = 0x01; /* write to page 1 */
+ w1_write_block(sl->master, w1_buf, 9);
+
+ if (w1_reset_select_slave(sl))
+ continue;
+ w1_buf[0] = W1_DS2438_COPY_SCRATCH;
+ w1_buf[1] = 0x01;
+ w1_write_block(sl->master, w1_buf, 2);
+ return 0;
+ }
+ }
+ return -1;
+}
+
+static int w1_ds2438_get_voltage(struct w1_slave *sl,
+ int adc_input, uint16_t *voltage)
+{
+ unsigned int retries = W1_DS2438_RETRIES;
+ u8 w1_buf[DS2438_PAGE_SIZE + 1 /*for CRC*/];
+ unsigned int tm = DS2438_MAX_CONVERSION_TIME;
+ unsigned long sleep_rem;
+ int ret;
+
+ mutex_lock(&sl->master->bus_mutex);
+
+ if (w1_ds2438_change_config_bit(sl, DS2438_STATUS_AD, adc_input)) {
+ ret = -1;
+ goto pre_unlock;
+ }
+
+ while (retries--) {
+ if (w1_reset_select_slave(sl))
+ continue;
+ w1_write_8(sl->master, W1_DS2438_CONVERT_VOLTAGE);
+
+ mutex_unlock(&sl->master->bus_mutex);
+ sleep_rem = msleep_interruptible(tm);
+ if (sleep_rem != 0) {
+ ret = -1;
+ goto post_unlock;
+ }
+
+ if (mutex_lock_interruptible(&sl->master->bus_mutex) != 0) {
+ ret = -1;
+ goto post_unlock;
+ }
+
+ break;
+ }
+
+ if (w1_ds2438_get_page(sl, 0, w1_buf) == 0) {
+ *voltage = (((uint16_t) w1_buf[DS2438_VOLTAGE_MSB]) << 8) | ((uint16_t) w1_buf[DS2438_VOLTAGE_LSB]);
+ ret = 0;
+ } else
+ ret = -1;
+
+pre_unlock:
+ mutex_unlock(&sl->master->bus_mutex);
+
+post_unlock:
+ return ret;
+}
+
+static int w1_ds2438_get_current(struct w1_slave *sl, int16_t *voltage)
+{
+ u8 w1_buf[DS2438_PAGE_SIZE + 1 /*for CRC*/];
+ int ret;
+
+ mutex_lock(&sl->master->bus_mutex);
+
+ if (w1_ds2438_get_page(sl, 0, w1_buf) == 0) {
+ /* The voltage measured across current sense resistor RSENS. */
+ *voltage = (((int16_t) w1_buf[DS2438_CURRENT_MSB]) << 8) | ((int16_t) w1_buf[DS2438_CURRENT_LSB]);
+ ret = 0;
+ } else
+ ret = -1;
+
+ mutex_unlock(&sl->master->bus_mutex);
+
+ return ret;
+}
+
+static ssize_t iad_write(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf,
+ loff_t off, size_t count)
+{
+ struct w1_slave *sl = kobj_to_w1_slave(kobj);
+ int ret;
+
+ if (count != 1 || off != 0)
+ return -EFAULT;
+
+ mutex_lock(&sl->master->bus_mutex);
+
+ if (w1_ds2438_change_config_bit(sl, DS2438_STATUS_IAD, *buf & 0x01) == 0)
+ ret = 1;
+ else
+ ret = -EIO;
+
+ mutex_unlock(&sl->master->bus_mutex);
+
+ return ret;
+}
+
+static ssize_t iad_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf,
+ loff_t off, size_t count)
+{
+ struct w1_slave *sl = kobj_to_w1_slave(kobj);
+ int ret;
+ int16_t voltage;
+
+ if (off != 0)
+ return 0;
+ if (!buf)
+ return -EINVAL;
+
+ if (w1_ds2438_get_current(sl, &voltage) == 0)
+ ret = snprintf(buf, count, "%i\n", voltage);
+ else
+ ret = -EIO;
+
+ return ret;
+}
+
+static ssize_t page0_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf,
+ loff_t off, size_t count)
+{
+ struct w1_slave *sl = kobj_to_w1_slave(kobj);
+ int ret;
+ u8 w1_buf[DS2438_PAGE_SIZE + 1 /*for CRC*/];
+
+ if (off != 0)
+ return 0;
+ if (!buf)
+ return -EINVAL;
+
+ mutex_lock(&sl->master->bus_mutex);
+
+ /* Read no more than page0 size */
+ if (count > DS2438_PAGE_SIZE)
+ count = DS2438_PAGE_SIZE;
+
+ if (w1_ds2438_get_page(sl, 0, w1_buf) == 0) {
+ memcpy(buf, &w1_buf, count);
+ ret = count;
+ } else
+ ret = -EIO;
+
+ mutex_unlock(&sl->master->bus_mutex);
+
+ return ret;
+}
+
+static ssize_t page1_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf,
+ loff_t off, size_t count)
+{
+ struct w1_slave *sl = kobj_to_w1_slave(kobj);
+ int ret;
+ u8 w1_buf[DS2438_PAGE_SIZE + 1 /*for CRC*/];
+
+ if (off != 0)
+ return 0;
+ if (!buf)
+ return -EINVAL;
+
+ mutex_lock(&sl->master->bus_mutex);
+
+ /* Read no more than page1 size */
+ if (count > DS2438_PAGE_SIZE)
+ count = DS2438_PAGE_SIZE;
+
+ if (w1_ds2438_get_page(sl, 1, w1_buf) == 0) {
+ memcpy(buf, &w1_buf, count);
+ ret = count;
+ } else
+ ret = -EIO;
+
+ mutex_unlock(&sl->master->bus_mutex);
+
+ return ret;
+}
+
+static ssize_t offset_write(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf,
+ loff_t off, size_t count)
+{
+ struct w1_slave *sl = kobj_to_w1_slave(kobj);
+ int ret;
+
+ mutex_lock(&sl->master->bus_mutex);
+
+ if (w1_ds2438_change_offset_register(sl, buf) == 0)
+ ret = count;
+ else
+ ret = -EIO;
+
+ mutex_unlock(&sl->master->bus_mutex);
+
+ return ret;
+}
+
+static ssize_t temperature_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf,
+ loff_t off, size_t count)
+{
+ struct w1_slave *sl = kobj_to_w1_slave(kobj);
+ int ret;
+ int16_t temp;
+
+ if (off != 0)
+ return 0;
+ if (!buf)
+ return -EINVAL;
+
+ if (w1_ds2438_get_temperature(sl, &temp) == 0)
+ ret = snprintf(buf, count, "%i\n", temp);
+ else
+ ret = -EIO;
+
+ return ret;
+}
+
+static ssize_t vad_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf,
+ loff_t off, size_t count)
+{
+ struct w1_slave *sl = kobj_to_w1_slave(kobj);
+ int ret;
+ uint16_t voltage;
+
+ if (off != 0)
+ return 0;
+ if (!buf)
+ return -EINVAL;
+
+ if (w1_ds2438_get_voltage(sl, DS2438_ADC_INPUT_VAD, &voltage) == 0)
+ ret = snprintf(buf, count, "%u\n", voltage);
+ else
+ ret = -EIO;
+
+ return ret;
+}
+
+static ssize_t vdd_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf,
+ loff_t off, size_t count)
+{
+ struct w1_slave *sl = kobj_to_w1_slave(kobj);
+ int ret;
+ uint16_t voltage;
+
+ if (off != 0)
+ return 0;
+ if (!buf)
+ return -EINVAL;
+
+ if (w1_ds2438_get_voltage(sl, DS2438_ADC_INPUT_VDD, &voltage) == 0)
+ ret = snprintf(buf, count, "%u\n", voltage);
+ else
+ ret = -EIO;
+
+ return ret;
+}
+
+static BIN_ATTR_RW(iad, 0);
+static BIN_ATTR_RO(page0, DS2438_PAGE_SIZE);
+static BIN_ATTR_RO(page1, DS2438_PAGE_SIZE);
+static BIN_ATTR_WO(offset, 2);
+static BIN_ATTR_RO(temperature, 0/* real length varies */);
+static BIN_ATTR_RO(vad, 0/* real length varies */);
+static BIN_ATTR_RO(vdd, 0/* real length varies */);
+
+static struct bin_attribute *w1_ds2438_bin_attrs[] = {
+ &bin_attr_iad,
+ &bin_attr_page0,
+ &bin_attr_page1,
+ &bin_attr_offset,
+ &bin_attr_temperature,
+ &bin_attr_vad,
+ &bin_attr_vdd,
+ NULL,
+};
+
+static const struct attribute_group w1_ds2438_group = {
+ .bin_attrs = w1_ds2438_bin_attrs,
+};
+
+static const struct attribute_group *w1_ds2438_groups[] = {
+ &w1_ds2438_group,
+ NULL,
+};
+
+static const struct w1_family_ops w1_ds2438_fops = {
+ .groups = w1_ds2438_groups,
+};
+
+static struct w1_family w1_ds2438_family = {
+ .fid = W1_FAMILY_DS2438,
+ .fops = &w1_ds2438_fops,
+};
+module_w1_family(w1_ds2438_family);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Mariusz Bialonczyk <manio@skyboo.net>");
+MODULE_DESCRIPTION("1-wire driver for Maxim/Dallas DS2438 Smart Battery Monitor");
+MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_DS2438));