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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/tty/serial/serial_mctrl_gpio.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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/tty/serial/serial_mctrl_gpio.c')
-rw-r--r--drivers/tty/serial/serial_mctrl_gpio.c388
1 files changed, 388 insertions, 0 deletions
diff --git a/drivers/tty/serial/serial_mctrl_gpio.c b/drivers/tty/serial/serial_mctrl_gpio.c
new file mode 100644
index 000000000..7d5aaa8d4
--- /dev/null
+++ b/drivers/tty/serial/serial_mctrl_gpio.c
@@ -0,0 +1,388 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Helpers for controlling modem lines via GPIO
+ *
+ * Copyright (C) 2014 Paratronic S.A.
+ */
+
+#include <linux/err.h>
+#include <linux/device.h>
+#include <linux/irq.h>
+#include <linux/gpio/consumer.h>
+#include <linux/termios.h>
+#include <linux/serial_core.h>
+#include <linux/module.h>
+#include <linux/property.h>
+
+#include "serial_mctrl_gpio.h"
+
+struct mctrl_gpios {
+ struct uart_port *port;
+ struct gpio_desc *gpio[UART_GPIO_MAX];
+ int irq[UART_GPIO_MAX];
+ unsigned int mctrl_prev;
+ bool mctrl_on;
+};
+
+static const struct {
+ const char *name;
+ unsigned int mctrl;
+ enum gpiod_flags flags;
+} mctrl_gpios_desc[UART_GPIO_MAX] = {
+ { "cts", TIOCM_CTS, GPIOD_IN, },
+ { "dsr", TIOCM_DSR, GPIOD_IN, },
+ { "dcd", TIOCM_CD, GPIOD_IN, },
+ { "rng", TIOCM_RNG, GPIOD_IN, },
+ { "rts", TIOCM_RTS, GPIOD_OUT_LOW, },
+ { "dtr", TIOCM_DTR, GPIOD_OUT_LOW, },
+};
+
+static bool mctrl_gpio_flags_is_dir_out(unsigned int idx)
+{
+ return mctrl_gpios_desc[idx].flags & GPIOD_FLAGS_BIT_DIR_OUT;
+}
+
+/**
+ * mctrl_gpio_set - set gpios according to mctrl state
+ * @gpios: gpios to set
+ * @mctrl: state to set
+ *
+ * Set the gpios according to the mctrl state.
+ */
+void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl)
+{
+ enum mctrl_gpio_idx i;
+ struct gpio_desc *desc_array[UART_GPIO_MAX];
+ DECLARE_BITMAP(values, UART_GPIO_MAX);
+ unsigned int count = 0;
+
+ if (gpios == NULL)
+ return;
+
+ for (i = 0; i < UART_GPIO_MAX; i++)
+ if (gpios->gpio[i] && mctrl_gpio_flags_is_dir_out(i)) {
+ desc_array[count] = gpios->gpio[i];
+ __assign_bit(count, values,
+ mctrl & mctrl_gpios_desc[i].mctrl);
+ count++;
+ }
+ gpiod_set_array_value(count, desc_array, NULL, values);
+}
+EXPORT_SYMBOL_GPL(mctrl_gpio_set);
+
+/**
+ * mctrl_gpio_to_gpiod - obtain gpio_desc of modem line index
+ * @gpios: gpios to look into
+ * @gidx: index of the modem line
+ * Returns: the gpio_desc structure associated to the modem line index
+ */
+struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios,
+ enum mctrl_gpio_idx gidx)
+{
+ if (gpios == NULL)
+ return NULL;
+
+ return gpios->gpio[gidx];
+}
+EXPORT_SYMBOL_GPL(mctrl_gpio_to_gpiod);
+
+/**
+ * mctrl_gpio_get - update mctrl with the gpios values.
+ * @gpios: gpios to get the info from
+ * @mctrl: mctrl to set
+ * Returns: modified mctrl (the same value as in @mctrl)
+ *
+ * Update mctrl with the gpios values.
+ */
+unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl)
+{
+ enum mctrl_gpio_idx i;
+
+ if (gpios == NULL)
+ return *mctrl;
+
+ for (i = 0; i < UART_GPIO_MAX; i++) {
+ if (gpios->gpio[i] && !mctrl_gpio_flags_is_dir_out(i)) {
+ if (gpiod_get_value(gpios->gpio[i]))
+ *mctrl |= mctrl_gpios_desc[i].mctrl;
+ else
+ *mctrl &= ~mctrl_gpios_desc[i].mctrl;
+ }
+ }
+
+ return *mctrl;
+}
+EXPORT_SYMBOL_GPL(mctrl_gpio_get);
+
+unsigned int
+mctrl_gpio_get_outputs(struct mctrl_gpios *gpios, unsigned int *mctrl)
+{
+ enum mctrl_gpio_idx i;
+
+ if (gpios == NULL)
+ return *mctrl;
+
+ for (i = 0; i < UART_GPIO_MAX; i++) {
+ if (gpios->gpio[i] && mctrl_gpio_flags_is_dir_out(i)) {
+ if (gpiod_get_value(gpios->gpio[i]))
+ *mctrl |= mctrl_gpios_desc[i].mctrl;
+ else
+ *mctrl &= ~mctrl_gpios_desc[i].mctrl;
+ }
+ }
+
+ return *mctrl;
+}
+EXPORT_SYMBOL_GPL(mctrl_gpio_get_outputs);
+
+struct mctrl_gpios *mctrl_gpio_init_noauto(struct device *dev, unsigned int idx)
+{
+ struct mctrl_gpios *gpios;
+ enum mctrl_gpio_idx i;
+
+ gpios = devm_kzalloc(dev, sizeof(*gpios), GFP_KERNEL);
+ if (!gpios)
+ return ERR_PTR(-ENOMEM);
+
+ for (i = 0; i < UART_GPIO_MAX; i++) {
+ char *gpio_str;
+ bool present;
+
+ /* Check if GPIO property exists and continue if not */
+ gpio_str = kasprintf(GFP_KERNEL, "%s-gpios",
+ mctrl_gpios_desc[i].name);
+ if (!gpio_str)
+ continue;
+
+ present = device_property_present(dev, gpio_str);
+ kfree(gpio_str);
+ if (!present)
+ continue;
+
+ gpios->gpio[i] =
+ devm_gpiod_get_index_optional(dev,
+ mctrl_gpios_desc[i].name,
+ idx,
+ mctrl_gpios_desc[i].flags);
+
+ if (IS_ERR(gpios->gpio[i]))
+ return ERR_CAST(gpios->gpio[i]);
+ }
+
+ return gpios;
+}
+EXPORT_SYMBOL_GPL(mctrl_gpio_init_noauto);
+
+#define MCTRL_ANY_DELTA (TIOCM_RI | TIOCM_DSR | TIOCM_CD | TIOCM_CTS)
+static irqreturn_t mctrl_gpio_irq_handle(int irq, void *context)
+{
+ struct mctrl_gpios *gpios = context;
+ struct uart_port *port = gpios->port;
+ u32 mctrl = gpios->mctrl_prev;
+ u32 mctrl_diff;
+ unsigned long flags;
+
+ mctrl_gpio_get(gpios, &mctrl);
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ mctrl_diff = mctrl ^ gpios->mctrl_prev;
+ gpios->mctrl_prev = mctrl;
+
+ if (mctrl_diff & MCTRL_ANY_DELTA && port->state != NULL) {
+ if ((mctrl_diff & mctrl) & TIOCM_RI)
+ port->icount.rng++;
+
+ if ((mctrl_diff & mctrl) & TIOCM_DSR)
+ port->icount.dsr++;
+
+ if (mctrl_diff & TIOCM_CD)
+ uart_handle_dcd_change(port, mctrl & TIOCM_CD);
+
+ if (mctrl_diff & TIOCM_CTS)
+ uart_handle_cts_change(port, mctrl & TIOCM_CTS);
+
+ wake_up_interruptible(&port->state->port.delta_msr_wait);
+ }
+
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+/**
+ * mctrl_gpio_init - initialize uart gpios
+ * @port: port to initialize gpios for
+ * @idx: index of the gpio in the @port's device
+ *
+ * This will get the {cts,rts,...}-gpios from device tree if they are present
+ * and request them, set direction etc, and return an allocated structure.
+ * `devm_*` functions are used, so there's no need to call mctrl_gpio_free().
+ * As this sets up the irq handling, make sure to not handle changes to the
+ * gpio input lines in your driver, too.
+ */
+struct mctrl_gpios *mctrl_gpio_init(struct uart_port *port, unsigned int idx)
+{
+ struct mctrl_gpios *gpios;
+ enum mctrl_gpio_idx i;
+
+ gpios = mctrl_gpio_init_noauto(port->dev, idx);
+ if (IS_ERR(gpios))
+ return gpios;
+
+ gpios->port = port;
+
+ for (i = 0; i < UART_GPIO_MAX; ++i) {
+ int ret;
+
+ if (!gpios->gpio[i] || mctrl_gpio_flags_is_dir_out(i))
+ continue;
+
+ ret = gpiod_to_irq(gpios->gpio[i]);
+ if (ret < 0) {
+ dev_err(port->dev,
+ "failed to find corresponding irq for %s (idx=%d, err=%d)\n",
+ mctrl_gpios_desc[i].name, idx, ret);
+ return ERR_PTR(ret);
+ }
+ gpios->irq[i] = ret;
+
+ /* irqs should only be enabled in .enable_ms */
+ irq_set_status_flags(gpios->irq[i], IRQ_NOAUTOEN);
+
+ ret = devm_request_irq(port->dev, gpios->irq[i],
+ mctrl_gpio_irq_handle,
+ IRQ_TYPE_EDGE_BOTH, dev_name(port->dev),
+ gpios);
+ if (ret) {
+ /* alternatively implement polling */
+ dev_err(port->dev,
+ "failed to request irq for %s (idx=%d, err=%d)\n",
+ mctrl_gpios_desc[i].name, idx, ret);
+ return ERR_PTR(ret);
+ }
+ }
+
+ return gpios;
+}
+EXPORT_SYMBOL_GPL(mctrl_gpio_init);
+
+/**
+ * mctrl_gpio_free - explicitly free uart gpios
+ * @dev: uart port's device
+ * @gpios: gpios structure to be freed
+ *
+ * This will free the requested gpios in mctrl_gpio_init(). As `devm_*`
+ * functions are used, there's generally no need to call this function.
+ */
+void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios)
+{
+ enum mctrl_gpio_idx i;
+
+ if (gpios == NULL)
+ return;
+
+ for (i = 0; i < UART_GPIO_MAX; i++) {
+ if (gpios->irq[i])
+ devm_free_irq(gpios->port->dev, gpios->irq[i], gpios);
+
+ if (gpios->gpio[i])
+ devm_gpiod_put(dev, gpios->gpio[i]);
+ }
+ devm_kfree(dev, gpios);
+}
+EXPORT_SYMBOL_GPL(mctrl_gpio_free);
+
+/**
+ * mctrl_gpio_enable_ms - enable irqs and handling of changes to the ms lines
+ * @gpios: gpios to enable
+ */
+void mctrl_gpio_enable_ms(struct mctrl_gpios *gpios)
+{
+ enum mctrl_gpio_idx i;
+
+ if (gpios == NULL)
+ return;
+
+ /* .enable_ms may be called multiple times */
+ if (gpios->mctrl_on)
+ return;
+
+ gpios->mctrl_on = true;
+
+ /* get initial status of modem lines GPIOs */
+ mctrl_gpio_get(gpios, &gpios->mctrl_prev);
+
+ for (i = 0; i < UART_GPIO_MAX; ++i) {
+ if (!gpios->irq[i])
+ continue;
+
+ enable_irq(gpios->irq[i]);
+ }
+}
+EXPORT_SYMBOL_GPL(mctrl_gpio_enable_ms);
+
+/**
+ * mctrl_gpio_disable_ms - disable irqs and handling of changes to the ms lines
+ * @gpios: gpios to disable
+ */
+void mctrl_gpio_disable_ms(struct mctrl_gpios *gpios)
+{
+ enum mctrl_gpio_idx i;
+
+ if (gpios == NULL)
+ return;
+
+ if (!gpios->mctrl_on)
+ return;
+
+ gpios->mctrl_on = false;
+
+ for (i = 0; i < UART_GPIO_MAX; ++i) {
+ if (!gpios->irq[i])
+ continue;
+
+ disable_irq(gpios->irq[i]);
+ }
+}
+EXPORT_SYMBOL_GPL(mctrl_gpio_disable_ms);
+
+void mctrl_gpio_enable_irq_wake(struct mctrl_gpios *gpios)
+{
+ enum mctrl_gpio_idx i;
+
+ if (!gpios)
+ return;
+
+ if (!gpios->mctrl_on)
+ return;
+
+ for (i = 0; i < UART_GPIO_MAX; ++i) {
+ if (!gpios->irq[i])
+ continue;
+
+ enable_irq_wake(gpios->irq[i]);
+ }
+}
+EXPORT_SYMBOL_GPL(mctrl_gpio_enable_irq_wake);
+
+void mctrl_gpio_disable_irq_wake(struct mctrl_gpios *gpios)
+{
+ enum mctrl_gpio_idx i;
+
+ if (!gpios)
+ return;
+
+ if (!gpios->mctrl_on)
+ return;
+
+ for (i = 0; i < UART_GPIO_MAX; ++i) {
+ if (!gpios->irq[i])
+ continue;
+
+ disable_irq_wake(gpios->irq[i]);
+ }
+}
+EXPORT_SYMBOL_GPL(mctrl_gpio_disable_irq_wake);
+
+MODULE_LICENSE("GPL");