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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/input/serio/ps2-gpio.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/input/serio/ps2-gpio.c')
-rw-r--r--drivers/input/serio/ps2-gpio.c507
1 files changed, 507 insertions, 0 deletions
diff --git a/drivers/input/serio/ps2-gpio.c b/drivers/input/serio/ps2-gpio.c
new file mode 100644
index 000000000..bc1dc4843
--- /dev/null
+++ b/drivers/input/serio/ps2-gpio.c
@@ -0,0 +1,507 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * GPIO based serio bus driver for bit banging the PS/2 protocol
+ *
+ * Author: Danilo Krummrich <danilokrummrich@dk-develop.de>
+ */
+
+#include <linux/gpio/consumer.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/serio.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/workqueue.h>
+#include <linux/completion.h>
+#include <linux/mutex.h>
+#include <linux/preempt.h>
+#include <linux/property.h>
+#include <linux/of.h>
+#include <linux/jiffies.h>
+#include <linux/delay.h>
+#include <linux/timekeeping.h>
+
+#define DRIVER_NAME "ps2-gpio"
+
+#define PS2_MODE_RX 0
+#define PS2_MODE_TX 1
+
+#define PS2_START_BIT 0
+#define PS2_DATA_BIT0 1
+#define PS2_DATA_BIT1 2
+#define PS2_DATA_BIT2 3
+#define PS2_DATA_BIT3 4
+#define PS2_DATA_BIT4 5
+#define PS2_DATA_BIT5 6
+#define PS2_DATA_BIT6 7
+#define PS2_DATA_BIT7 8
+#define PS2_PARITY_BIT 9
+#define PS2_STOP_BIT 10
+#define PS2_ACK_BIT 11
+
+#define PS2_DEV_RET_ACK 0xfa
+#define PS2_DEV_RET_NACK 0xfe
+
+#define PS2_CMD_RESEND 0xfe
+
+/*
+ * The PS2 protocol specifies a clock frequency between 10kHz and 16.7kHz,
+ * therefore the maximal interrupt interval should be 100us and the minimum
+ * interrupt interval should be ~60us. Let's allow +/- 20us for frequency
+ * deviations and interrupt latency.
+ *
+ * The data line must be samples after ~30us to 50us after the falling edge,
+ * since the device updates the data line at the rising edge.
+ *
+ * ___ ______ ______ ______ ___
+ * \ / \ / \ / \ /
+ * \ / \ / \ / \ /
+ * \______/ \______/ \______/ \______/
+ *
+ * |-----------------| |--------|
+ * 60us/100us 30us/50us
+ */
+#define PS2_CLK_FREQ_MIN_HZ 10000
+#define PS2_CLK_FREQ_MAX_HZ 16700
+#define PS2_CLK_MIN_INTERVAL_US ((1000 * 1000) / PS2_CLK_FREQ_MAX_HZ)
+#define PS2_CLK_MAX_INTERVAL_US ((1000 * 1000) / PS2_CLK_FREQ_MIN_HZ)
+#define PS2_IRQ_MIN_INTERVAL_US (PS2_CLK_MIN_INTERVAL_US - 20)
+#define PS2_IRQ_MAX_INTERVAL_US (PS2_CLK_MAX_INTERVAL_US + 20)
+
+struct ps2_gpio_data {
+ struct device *dev;
+ struct serio *serio;
+ unsigned char mode;
+ struct gpio_desc *gpio_clk;
+ struct gpio_desc *gpio_data;
+ bool write_enable;
+ int irq;
+ ktime_t t_irq_now;
+ ktime_t t_irq_last;
+ struct {
+ unsigned char cnt;
+ unsigned char byte;
+ } rx;
+ struct {
+ unsigned char cnt;
+ unsigned char byte;
+ ktime_t t_xfer_start;
+ ktime_t t_xfer_end;
+ struct completion complete;
+ struct mutex mutex;
+ struct delayed_work work;
+ } tx;
+};
+
+static int ps2_gpio_open(struct serio *serio)
+{
+ struct ps2_gpio_data *drvdata = serio->port_data;
+
+ drvdata->t_irq_last = 0;
+ drvdata->tx.t_xfer_end = 0;
+
+ enable_irq(drvdata->irq);
+ return 0;
+}
+
+static void ps2_gpio_close(struct serio *serio)
+{
+ struct ps2_gpio_data *drvdata = serio->port_data;
+
+ flush_delayed_work(&drvdata->tx.work);
+ disable_irq(drvdata->irq);
+}
+
+static int __ps2_gpio_write(struct serio *serio, unsigned char val)
+{
+ struct ps2_gpio_data *drvdata = serio->port_data;
+
+ disable_irq_nosync(drvdata->irq);
+ gpiod_direction_output(drvdata->gpio_clk, 0);
+
+ drvdata->mode = PS2_MODE_TX;
+ drvdata->tx.byte = val;
+
+ schedule_delayed_work(&drvdata->tx.work, usecs_to_jiffies(200));
+
+ return 0;
+}
+
+static int ps2_gpio_write(struct serio *serio, unsigned char val)
+{
+ struct ps2_gpio_data *drvdata = serio->port_data;
+ int ret = 0;
+
+ if (in_task()) {
+ mutex_lock(&drvdata->tx.mutex);
+ __ps2_gpio_write(serio, val);
+ if (!wait_for_completion_timeout(&drvdata->tx.complete,
+ msecs_to_jiffies(10000)))
+ ret = SERIO_TIMEOUT;
+ mutex_unlock(&drvdata->tx.mutex);
+ } else {
+ __ps2_gpio_write(serio, val);
+ }
+
+ return ret;
+}
+
+static void ps2_gpio_tx_work_fn(struct work_struct *work)
+{
+ struct delayed_work *dwork = to_delayed_work(work);
+ struct ps2_gpio_data *drvdata = container_of(dwork,
+ struct ps2_gpio_data,
+ tx.work);
+
+ drvdata->tx.t_xfer_start = ktime_get();
+ enable_irq(drvdata->irq);
+ gpiod_direction_output(drvdata->gpio_data, 0);
+ gpiod_direction_input(drvdata->gpio_clk);
+}
+
+static irqreturn_t ps2_gpio_irq_rx(struct ps2_gpio_data *drvdata)
+{
+ unsigned char byte, cnt;
+ int data;
+ int rxflags = 0;
+ s64 us_delta;
+
+ byte = drvdata->rx.byte;
+ cnt = drvdata->rx.cnt;
+
+ drvdata->t_irq_now = ktime_get();
+
+ /*
+ * We need to consider spurious interrupts happening right after
+ * a TX xfer finished.
+ */
+ us_delta = ktime_us_delta(drvdata->t_irq_now, drvdata->tx.t_xfer_end);
+ if (unlikely(us_delta < PS2_IRQ_MIN_INTERVAL_US))
+ goto end;
+
+ us_delta = ktime_us_delta(drvdata->t_irq_now, drvdata->t_irq_last);
+ if (us_delta > PS2_IRQ_MAX_INTERVAL_US && cnt) {
+ dev_err(drvdata->dev,
+ "RX: timeout, probably we missed an interrupt\n");
+ goto err;
+ } else if (unlikely(us_delta < PS2_IRQ_MIN_INTERVAL_US)) {
+ /* Ignore spurious IRQs. */
+ goto end;
+ }
+ drvdata->t_irq_last = drvdata->t_irq_now;
+
+ data = gpiod_get_value(drvdata->gpio_data);
+ if (unlikely(data < 0)) {
+ dev_err(drvdata->dev, "RX: failed to get data gpio val: %d\n",
+ data);
+ goto err;
+ }
+
+ switch (cnt) {
+ case PS2_START_BIT:
+ /* start bit should be low */
+ if (unlikely(data)) {
+ dev_err(drvdata->dev, "RX: start bit should be low\n");
+ goto err;
+ }
+ break;
+ case PS2_DATA_BIT0:
+ case PS2_DATA_BIT1:
+ case PS2_DATA_BIT2:
+ case PS2_DATA_BIT3:
+ case PS2_DATA_BIT4:
+ case PS2_DATA_BIT5:
+ case PS2_DATA_BIT6:
+ case PS2_DATA_BIT7:
+ /* processing data bits */
+ if (data)
+ byte |= (data << (cnt - 1));
+ break;
+ case PS2_PARITY_BIT:
+ /* check odd parity */
+ if (!((hweight8(byte) & 1) ^ data)) {
+ rxflags |= SERIO_PARITY;
+ dev_warn(drvdata->dev, "RX: parity error\n");
+ if (!drvdata->write_enable)
+ goto err;
+ }
+ break;
+ case PS2_STOP_BIT:
+ /* stop bit should be high */
+ if (unlikely(!data)) {
+ dev_err(drvdata->dev, "RX: stop bit should be high\n");
+ goto err;
+ }
+
+ /*
+ * Do not send spurious ACK's and NACK's when write fn is
+ * not provided.
+ */
+ if (!drvdata->write_enable) {
+ if (byte == PS2_DEV_RET_NACK)
+ goto err;
+ else if (byte == PS2_DEV_RET_ACK)
+ break;
+ }
+
+ serio_interrupt(drvdata->serio, byte, rxflags);
+ dev_dbg(drvdata->dev, "RX: sending byte 0x%x\n", byte);
+
+ cnt = byte = 0;
+
+ goto end; /* success */
+ default:
+ dev_err(drvdata->dev, "RX: got out of sync with the device\n");
+ goto err;
+ }
+
+ cnt++;
+ goto end; /* success */
+
+err:
+ cnt = byte = 0;
+ __ps2_gpio_write(drvdata->serio, PS2_CMD_RESEND);
+end:
+ drvdata->rx.cnt = cnt;
+ drvdata->rx.byte = byte;
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t ps2_gpio_irq_tx(struct ps2_gpio_data *drvdata)
+{
+ unsigned char byte, cnt;
+ int data;
+ s64 us_delta;
+
+ cnt = drvdata->tx.cnt;
+ byte = drvdata->tx.byte;
+
+ drvdata->t_irq_now = ktime_get();
+
+ /*
+ * There might be pending IRQs since we disabled IRQs in
+ * __ps2_gpio_write(). We can expect at least one clock period until
+ * the device generates the first falling edge after releasing the
+ * clock line.
+ */
+ us_delta = ktime_us_delta(drvdata->t_irq_now,
+ drvdata->tx.t_xfer_start);
+ if (unlikely(us_delta < PS2_CLK_MIN_INTERVAL_US))
+ goto end;
+
+ us_delta = ktime_us_delta(drvdata->t_irq_now, drvdata->t_irq_last);
+ if (us_delta > PS2_IRQ_MAX_INTERVAL_US && cnt > 1) {
+ dev_err(drvdata->dev,
+ "TX: timeout, probably we missed an interrupt\n");
+ goto err;
+ } else if (unlikely(us_delta < PS2_IRQ_MIN_INTERVAL_US)) {
+ /* Ignore spurious IRQs. */
+ goto end;
+ }
+ drvdata->t_irq_last = drvdata->t_irq_now;
+
+ switch (cnt) {
+ case PS2_START_BIT:
+ /* should never happen */
+ dev_err(drvdata->dev,
+ "TX: start bit should have been sent already\n");
+ goto err;
+ case PS2_DATA_BIT0:
+ case PS2_DATA_BIT1:
+ case PS2_DATA_BIT2:
+ case PS2_DATA_BIT3:
+ case PS2_DATA_BIT4:
+ case PS2_DATA_BIT5:
+ case PS2_DATA_BIT6:
+ case PS2_DATA_BIT7:
+ data = byte & BIT(cnt - 1);
+ gpiod_set_value(drvdata->gpio_data, data);
+ break;
+ case PS2_PARITY_BIT:
+ /* do odd parity */
+ data = !(hweight8(byte) & 1);
+ gpiod_set_value(drvdata->gpio_data, data);
+ break;
+ case PS2_STOP_BIT:
+ /* release data line to generate stop bit */
+ gpiod_direction_input(drvdata->gpio_data);
+ break;
+ case PS2_ACK_BIT:
+ data = gpiod_get_value(drvdata->gpio_data);
+ if (data) {
+ dev_warn(drvdata->dev, "TX: received NACK, retry\n");
+ goto err;
+ }
+
+ drvdata->tx.t_xfer_end = ktime_get();
+ drvdata->mode = PS2_MODE_RX;
+ complete(&drvdata->tx.complete);
+
+ cnt = 1;
+ goto end; /* success */
+ default:
+ /*
+ * Probably we missed the stop bit. Therefore we release data
+ * line and try again.
+ */
+ gpiod_direction_input(drvdata->gpio_data);
+ dev_err(drvdata->dev, "TX: got out of sync with the device\n");
+ goto err;
+ }
+
+ cnt++;
+ goto end; /* success */
+
+err:
+ cnt = 1;
+ gpiod_direction_input(drvdata->gpio_data);
+ __ps2_gpio_write(drvdata->serio, drvdata->tx.byte);
+end:
+ drvdata->tx.cnt = cnt;
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t ps2_gpio_irq(int irq, void *dev_id)
+{
+ struct ps2_gpio_data *drvdata = dev_id;
+
+ return drvdata->mode ? ps2_gpio_irq_tx(drvdata) :
+ ps2_gpio_irq_rx(drvdata);
+}
+
+static int ps2_gpio_get_props(struct device *dev,
+ struct ps2_gpio_data *drvdata)
+{
+ enum gpiod_flags gflags;
+
+ /* Enforce open drain, since this is required by the PS/2 bus. */
+ gflags = GPIOD_IN | GPIOD_FLAGS_BIT_OPEN_DRAIN;
+
+ drvdata->gpio_data = devm_gpiod_get(dev, "data", gflags);
+ if (IS_ERR(drvdata->gpio_data)) {
+ dev_err(dev, "failed to request data gpio: %ld",
+ PTR_ERR(drvdata->gpio_data));
+ return PTR_ERR(drvdata->gpio_data);
+ }
+
+ drvdata->gpio_clk = devm_gpiod_get(dev, "clk", gflags);
+ if (IS_ERR(drvdata->gpio_clk)) {
+ dev_err(dev, "failed to request clock gpio: %ld",
+ PTR_ERR(drvdata->gpio_clk));
+ return PTR_ERR(drvdata->gpio_clk);
+ }
+
+ drvdata->write_enable = device_property_read_bool(dev,
+ "write-enable");
+
+ return 0;
+}
+
+static int ps2_gpio_probe(struct platform_device *pdev)
+{
+ struct ps2_gpio_data *drvdata;
+ struct serio *serio;
+ struct device *dev = &pdev->dev;
+ int error;
+
+ drvdata = devm_kzalloc(dev, sizeof(struct ps2_gpio_data), GFP_KERNEL);
+ serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
+ if (!drvdata || !serio) {
+ error = -ENOMEM;
+ goto err_free_serio;
+ }
+
+ error = ps2_gpio_get_props(dev, drvdata);
+ if (error)
+ goto err_free_serio;
+
+ if (gpiod_cansleep(drvdata->gpio_data) ||
+ gpiod_cansleep(drvdata->gpio_clk)) {
+ dev_err(dev, "GPIO data or clk are connected via slow bus\n");
+ error = -EINVAL;
+ goto err_free_serio;
+ }
+
+ drvdata->irq = platform_get_irq(pdev, 0);
+ if (drvdata->irq < 0) {
+ error = drvdata->irq;
+ goto err_free_serio;
+ }
+
+ error = devm_request_irq(dev, drvdata->irq, ps2_gpio_irq,
+ IRQF_NO_THREAD, DRIVER_NAME, drvdata);
+ if (error) {
+ dev_err(dev, "failed to request irq %d: %d\n",
+ drvdata->irq, error);
+ goto err_free_serio;
+ }
+
+ /* Keep irq disabled until serio->open is called. */
+ disable_irq(drvdata->irq);
+
+ serio->id.type = SERIO_8042;
+ serio->open = ps2_gpio_open;
+ serio->close = ps2_gpio_close;
+ /*
+ * Write can be enabled in platform/dt data, but possibly it will not
+ * work because of the tough timings.
+ */
+ serio->write = drvdata->write_enable ? ps2_gpio_write : NULL;
+ serio->port_data = drvdata;
+ serio->dev.parent = dev;
+ strscpy(serio->name, dev_name(dev), sizeof(serio->name));
+ strscpy(serio->phys, dev_name(dev), sizeof(serio->phys));
+
+ drvdata->serio = serio;
+ drvdata->dev = dev;
+ drvdata->mode = PS2_MODE_RX;
+
+ /*
+ * Tx count always starts at 1, as the start bit is sent implicitly by
+ * host-to-device communication initialization.
+ */
+ drvdata->tx.cnt = 1;
+
+ INIT_DELAYED_WORK(&drvdata->tx.work, ps2_gpio_tx_work_fn);
+ init_completion(&drvdata->tx.complete);
+ mutex_init(&drvdata->tx.mutex);
+
+ serio_register_port(serio);
+ platform_set_drvdata(pdev, drvdata);
+
+ return 0; /* success */
+
+err_free_serio:
+ kfree(serio);
+ return error;
+}
+
+static int ps2_gpio_remove(struct platform_device *pdev)
+{
+ struct ps2_gpio_data *drvdata = platform_get_drvdata(pdev);
+
+ serio_unregister_port(drvdata->serio);
+ return 0;
+}
+
+#if defined(CONFIG_OF)
+static const struct of_device_id ps2_gpio_match[] = {
+ { .compatible = "ps2-gpio", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, ps2_gpio_match);
+#endif
+
+static struct platform_driver ps2_gpio_driver = {
+ .probe = ps2_gpio_probe,
+ .remove = ps2_gpio_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .of_match_table = of_match_ptr(ps2_gpio_match),
+ },
+};
+module_platform_driver(ps2_gpio_driver);
+
+MODULE_AUTHOR("Danilo Krummrich <danilokrummrich@dk-develop.de>");
+MODULE_DESCRIPTION("GPIO PS2 driver");
+MODULE_LICENSE("GPL v2");