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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/spi/spi-lm70llp.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/spi/spi-lm70llp.c')
-rw-r--r--drivers/spi/spi-lm70llp.c328
1 files changed, 328 insertions, 0 deletions
diff --git a/drivers/spi/spi-lm70llp.c b/drivers/spi/spi-lm70llp.c
new file mode 100644
index 000000000..ead0507c6
--- /dev/null
+++ b/drivers/spi/spi-lm70llp.c
@@ -0,0 +1,328 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Driver for LM70EVAL-LLP board for the LM70 sensor
+ *
+ * Copyright (C) 2006 Kaiwan N Billimoria <kaiwan@designergraphix.com>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/parport.h>
+#include <linux/sysfs.h>
+#include <linux/workqueue.h>
+
+#include <linux/spi/spi.h>
+#include <linux/spi/spi_bitbang.h>
+
+/*
+ * The LM70 communicates with a host processor using a 3-wire variant of
+ * the SPI/Microwire bus interface. This driver specifically supports an
+ * NS LM70 LLP Evaluation Board, interfacing to a PC using its parallel
+ * port to bitbang an SPI-parport bridge. Accordingly, this is an SPI
+ * master controller driver. The hwmon/lm70 driver is a "SPI protocol
+ * driver", layered on top of this one and usable without the lm70llp.
+ *
+ * Datasheet and Schematic:
+ * The LM70 is a temperature sensor chip from National Semiconductor; its
+ * datasheet is available at http://www.national.com/pf/LM/LM70.html
+ * The schematic for this particular board (the LM70EVAL-LLP) is
+ * available (on page 4) here:
+ * http://www.national.com/appinfo/tempsensors/files/LM70LLPEVALmanual.pdf
+ *
+ * Also see Documentation/spi/spi-lm70llp.rst. The SPI<->parport code here is
+ * (heavily) based on spi-butterfly by David Brownell.
+ *
+ * The LM70 LLP connects to the PC parallel port in the following manner:
+ *
+ * Parallel LM70 LLP
+ * Port Direction JP2 Header
+ * ----------- --------- ------------
+ * D0 2 - -
+ * D1 3 --> V+ 5
+ * D2 4 --> V+ 5
+ * D3 5 --> V+ 5
+ * D4 6 --> V+ 5
+ * D5 7 --> nCS 8
+ * D6 8 --> SCLK 3
+ * D7 9 --> SI/O 5
+ * GND 25 - GND 7
+ * Select 13 <-- SI/O 1
+ *
+ * Note that parport pin 13 actually gets inverted by the transistor
+ * arrangement which lets either the parport or the LM70 drive the
+ * SI/SO signal (see the schematic for details).
+ */
+
+#define DRVNAME "spi-lm70llp"
+
+#define lm70_INIT 0xBE
+#define SIO 0x10
+#define nCS 0x20
+#define SCLK 0x40
+
+/*-------------------------------------------------------------------------*/
+
+struct spi_lm70llp {
+ struct spi_bitbang bitbang;
+ struct parport *port;
+ struct pardevice *pd;
+ struct spi_device *spidev_lm70;
+ struct spi_board_info info;
+ //struct device *dev;
+};
+
+/* REVISIT : ugly global ; provides "exclusive open" facility */
+static struct spi_lm70llp *lm70llp;
+
+/*-------------------------------------------------------------------*/
+
+static inline struct spi_lm70llp *spidev_to_pp(struct spi_device *spi)
+{
+ return spi->controller_data;
+}
+
+/*---------------------- LM70 LLP eval board-specific inlines follow */
+
+/* NOTE: we don't actually need to reread the output values, since they'll
+ * still be what we wrote before. Plus, going through parport builds in
+ * a ~1ms/operation delay; these SPI transfers could easily be faster.
+ */
+
+static inline void deassertCS(struct spi_lm70llp *pp)
+{
+ u8 data = parport_read_data(pp->port);
+
+ data &= ~0x80; /* pull D7/SI-out low while de-asserted */
+ parport_write_data(pp->port, data | nCS);
+}
+
+static inline void assertCS(struct spi_lm70llp *pp)
+{
+ u8 data = parport_read_data(pp->port);
+
+ data |= 0x80; /* pull D7/SI-out high so lm70 drives SO-in */
+ parport_write_data(pp->port, data & ~nCS);
+}
+
+static inline void clkHigh(struct spi_lm70llp *pp)
+{
+ u8 data = parport_read_data(pp->port);
+
+ parport_write_data(pp->port, data | SCLK);
+}
+
+static inline void clkLow(struct spi_lm70llp *pp)
+{
+ u8 data = parport_read_data(pp->port);
+
+ parport_write_data(pp->port, data & ~SCLK);
+}
+
+/*------------------------- SPI-LM70-specific inlines ----------------------*/
+
+static inline void spidelay(unsigned d)
+{
+ udelay(d);
+}
+
+static inline void setsck(struct spi_device *s, int is_on)
+{
+ struct spi_lm70llp *pp = spidev_to_pp(s);
+
+ if (is_on)
+ clkHigh(pp);
+ else
+ clkLow(pp);
+}
+
+static inline void setmosi(struct spi_device *s, int is_on)
+{
+ /* FIXME update D7 ... this way we can put the chip
+ * into shutdown mode and read the manufacturer ID,
+ * but we can't put it back into operational mode.
+ */
+}
+
+/*
+ * getmiso:
+ * Why do we return 0 when the SIO line is high and vice-versa?
+ * The fact is, the lm70 eval board from NS (which this driver drives),
+ * is wired in just such a way : when the lm70's SIO goes high, a transistor
+ * switches it to low reflecting this on the parport (pin 13), and vice-versa.
+ */
+static inline int getmiso(struct spi_device *s)
+{
+ struct spi_lm70llp *pp = spidev_to_pp(s);
+
+ return ((SIO == (parport_read_status(pp->port) & SIO)) ? 0 : 1);
+}
+
+/*--------------------------------------------------------------------*/
+
+#include "spi-bitbang-txrx.h"
+
+static void lm70_chipselect(struct spi_device *spi, int value)
+{
+ struct spi_lm70llp *pp = spidev_to_pp(spi);
+
+ if (value)
+ assertCS(pp);
+ else
+ deassertCS(pp);
+}
+
+/*
+ * Our actual bitbanger routine.
+ */
+static u32 lm70_txrx(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits,
+ unsigned flags)
+{
+ return bitbang_txrx_be_cpha0(spi, nsecs, 0, flags, word, bits);
+}
+
+static void spi_lm70llp_attach(struct parport *p)
+{
+ struct pardevice *pd;
+ struct spi_lm70llp *pp;
+ struct spi_master *master;
+ int status;
+ struct pardev_cb lm70llp_cb;
+
+ if (lm70llp) {
+ pr_warn("spi_lm70llp instance already loaded. Aborting.\n");
+ return;
+ }
+
+ /* TODO: this just _assumes_ a lm70 is there ... no probe;
+ * the lm70 driver could verify it, reading the manf ID.
+ */
+
+ master = spi_alloc_master(p->physport->dev, sizeof(*pp));
+ if (!master) {
+ status = -ENOMEM;
+ goto out_fail;
+ }
+ pp = spi_master_get_devdata(master);
+
+ /*
+ * SPI and bitbang hookup.
+ */
+ pp->bitbang.master = master;
+ pp->bitbang.chipselect = lm70_chipselect;
+ pp->bitbang.txrx_word[SPI_MODE_0] = lm70_txrx;
+ pp->bitbang.flags = SPI_3WIRE;
+
+ /*
+ * Parport hookup
+ */
+ pp->port = p;
+ memset(&lm70llp_cb, 0, sizeof(lm70llp_cb));
+ lm70llp_cb.private = pp;
+ lm70llp_cb.flags = PARPORT_FLAG_EXCL;
+ pd = parport_register_dev_model(p, DRVNAME, &lm70llp_cb, 0);
+
+ if (!pd) {
+ status = -ENOMEM;
+ goto out_free_master;
+ }
+ pp->pd = pd;
+
+ status = parport_claim(pd);
+ if (status < 0)
+ goto out_parport_unreg;
+
+ /*
+ * Start SPI ...
+ */
+ status = spi_bitbang_start(&pp->bitbang);
+ if (status < 0) {
+ dev_warn(&pd->dev, "spi_bitbang_start failed with status %d\n",
+ status);
+ goto out_off_and_release;
+ }
+
+ /*
+ * The modalias name MUST match the device_driver name
+ * for the bus glue code to match and subsequently bind them.
+ * We are binding to the generic drivers/hwmon/lm70.c device
+ * driver.
+ */
+ strcpy(pp->info.modalias, "lm70");
+ pp->info.max_speed_hz = 6 * 1000 * 1000;
+ pp->info.chip_select = 0;
+ pp->info.mode = SPI_3WIRE | SPI_MODE_0;
+
+ /* power up the chip, and let the LM70 control SI/SO */
+ parport_write_data(pp->port, lm70_INIT);
+
+ /* Enable access to our primary data structure via
+ * the board info's (void *)controller_data.
+ */
+ pp->info.controller_data = pp;
+ pp->spidev_lm70 = spi_new_device(pp->bitbang.master, &pp->info);
+ if (pp->spidev_lm70)
+ dev_dbg(&pp->spidev_lm70->dev, "spidev_lm70 at %s\n",
+ dev_name(&pp->spidev_lm70->dev));
+ else {
+ dev_warn(&pd->dev, "spi_new_device failed\n");
+ status = -ENODEV;
+ goto out_bitbang_stop;
+ }
+ pp->spidev_lm70->bits_per_word = 8;
+
+ lm70llp = pp;
+ return;
+
+out_bitbang_stop:
+ spi_bitbang_stop(&pp->bitbang);
+out_off_and_release:
+ /* power down */
+ parport_write_data(pp->port, 0);
+ mdelay(10);
+ parport_release(pp->pd);
+out_parport_unreg:
+ parport_unregister_device(pd);
+out_free_master:
+ spi_master_put(master);
+out_fail:
+ pr_info("spi_lm70llp probe fail, status %d\n", status);
+}
+
+static void spi_lm70llp_detach(struct parport *p)
+{
+ struct spi_lm70llp *pp;
+
+ if (!lm70llp || lm70llp->port != p)
+ return;
+
+ pp = lm70llp;
+ spi_bitbang_stop(&pp->bitbang);
+
+ /* power down */
+ parport_write_data(pp->port, 0);
+
+ parport_release(pp->pd);
+ parport_unregister_device(pp->pd);
+
+ spi_master_put(pp->bitbang.master);
+
+ lm70llp = NULL;
+}
+
+static struct parport_driver spi_lm70llp_drv = {
+ .name = DRVNAME,
+ .match_port = spi_lm70llp_attach,
+ .detach = spi_lm70llp_detach,
+ .devmodel = true,
+};
+module_parport_driver(spi_lm70llp_drv);
+
+MODULE_AUTHOR("Kaiwan N Billimoria <kaiwan@designergraphix.com>");
+MODULE_DESCRIPTION(
+ "Parport adapter for the National Semiconductor LM70 LLP eval board");
+MODULE_LICENSE("GPL");