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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/net/usb/plusb.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'drivers/net/usb/plusb.c')
-rw-r--r--drivers/net/usb/plusb.c153
1 files changed, 153 insertions, 0 deletions
diff --git a/drivers/net/usb/plusb.c b/drivers/net/usb/plusb.c
new file mode 100644
index 000000000..289411485
--- /dev/null
+++ b/drivers/net/usb/plusb.c
@@ -0,0 +1,153 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * PL-2301/2302 USB host-to-host link cables
+ * Copyright (C) 2000-2005 by David Brownell
+ */
+
+// #define DEBUG // error path messages, extra info
+// #define VERBOSE // more; success messages
+
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/workqueue.h>
+#include <linux/mii.h>
+#include <linux/usb.h>
+#include <linux/usb/usbnet.h>
+
+
+/*
+ * Prolific PL-2301/PL-2302 driver ... http://www.prolific.com.tw/
+ *
+ * The protocol and handshaking used here should be bug-compatible
+ * with the Linux 2.2 "plusb" driver, by Deti Fliegl.
+ *
+ * HEADS UP: this handshaking isn't all that robust. This driver
+ * gets confused easily if you unplug one end of the cable then
+ * try to connect it again; you'll need to restart both ends. The
+ * "naplink" software (used by some PlayStation/2 developers) does
+ * the handshaking much better! Also, sometimes this hardware
+ * seems to get wedged under load. Prolific docs are weak, and
+ * don't identify differences between PL2301 and PL2302, much less
+ * anything to explain the different PL2302 versions observed.
+ *
+ * NOTE: pl2501 has several modes, including pl2301 and pl2302
+ * compatibility. Some docs suggest the difference between 2301
+ * and 2302 is only to make MS-Windows use a different driver...
+ *
+ * pl25a1 glue based on patch from Tony Gibbs. Prolific "docs" on
+ * this chip are as usual incomplete about what control messages
+ * are supported.
+ */
+
+/*
+ * Bits 0-4 can be used for software handshaking; they're set from
+ * one end, cleared from the other, "read" with the interrupt byte.
+ */
+#define PL_S_EN (1<<7) /* (feature only) suspend enable */
+/* reserved bit -- rx ready (6) ? */
+#define PL_TX_READY (1<<5) /* (interrupt only) transmit ready */
+#define PL_RESET_OUT (1<<4) /* reset output pipe */
+#define PL_RESET_IN (1<<3) /* reset input pipe */
+#define PL_TX_C (1<<2) /* transmission complete */
+#define PL_TX_REQ (1<<1) /* transmission received */
+#define PL_PEER_E (1<<0) /* peer exists */
+
+static inline int
+pl_vendor_req(struct usbnet *dev, u8 req, u8 val, u8 index)
+{
+ return usbnet_write_cmd(dev, req, USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+ val, index, NULL, 0);
+}
+
+static inline int
+pl_set_QuickLink_features(struct usbnet *dev, int val)
+{
+ return pl_vendor_req(dev, 3, (u8) val, 0);
+}
+
+static int pl_reset(struct usbnet *dev)
+{
+ int status;
+
+ /* some units seem to need this reset, others reject it utterly.
+ * FIXME be more like "naplink" or windows drivers.
+ */
+ status = pl_set_QuickLink_features(dev,
+ PL_S_EN|PL_RESET_OUT|PL_RESET_IN|PL_PEER_E);
+ if (status != 0 && netif_msg_probe(dev))
+ netif_dbg(dev, link, dev->net, "pl_reset --> %d\n", status);
+ return 0;
+}
+
+static const struct driver_info prolific_info = {
+ .description = "Prolific PL-2301/PL-2302/PL-25A1/PL-27A1",
+ .flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT,
+ /* some PL-2302 versions seem to fail usb_set_interface() */
+ .reset = pl_reset,
+};
+
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Proilific's name won't normally be on the cables, and
+ * may not be on the device.
+ */
+
+static const struct usb_device_id products [] = {
+
+/* full speed cables */
+{
+ USB_DEVICE(0x067b, 0x0000), // PL-2301
+ .driver_info = (unsigned long) &prolific_info,
+}, {
+ USB_DEVICE(0x067b, 0x0001), // PL-2302
+ .driver_info = (unsigned long) &prolific_info,
+},
+
+/* high speed cables */
+{
+ USB_DEVICE(0x067b, 0x25a1), /* PL-25A1, no eeprom */
+ .driver_info = (unsigned long) &prolific_info,
+}, {
+ USB_DEVICE(0x050d, 0x258a), /* Belkin F5U258/F5U279 (PL-25A1) */
+ .driver_info = (unsigned long) &prolific_info,
+}, {
+ USB_DEVICE(0x3923, 0x7825), /* National Instruments USB
+ * Host-to-Host Cable
+ */
+ .driver_info = (unsigned long) &prolific_info,
+
+},
+
+/* super speed cables */
+{
+ USB_DEVICE(0x067b, 0x27a1), /* PL-27A1, no eeprom
+ * also: goobay Active USB 3.0
+ * Data Link,
+ * Unitek Y-3501
+ */
+ .driver_info = (unsigned long) &prolific_info,
+},
+
+ { }, // END
+};
+MODULE_DEVICE_TABLE(usb, products);
+
+static struct usb_driver plusb_driver = {
+ .name = "plusb",
+ .id_table = products,
+ .probe = usbnet_probe,
+ .disconnect = usbnet_disconnect,
+ .suspend = usbnet_suspend,
+ .resume = usbnet_resume,
+ .disable_hub_initiated_lpm = 1,
+};
+
+module_usb_driver(plusb_driver);
+
+MODULE_AUTHOR("David Brownell");
+MODULE_DESCRIPTION("Prolific PL-2301/2302/25A1/27A1 USB Host to Host Link Driver");
+MODULE_LICENSE("GPL");