Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 359 insertions, 0 deletions

diff --git a/drivers/misc/keba/lan9252.c b/drivers/misc/keba/lan9252.c
new file mode 100644
index 000000000..874dd50fa
--- /dev/null
+++ b/drivers/misc/keba/lan9252.c
@@ -0,0 +1,359 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) KEBA Industrial Automation Gmbh 2024
+ *
+ * Driver for LAN9252 on KEBA CP500 devices
+ *
+ * This driver is used for updating the configuration of the LAN9252 controller
+ * on KEBA CP500 devices. The LAN9252 is connected over SPI, which is also named
+ * PDI.
+ */
+
+#include <linux/spi/spi.h>
+#include <linux/mii.h>
+
+/* SPI commands */
+#define LAN9252_SPI_READ	0x3
+#define LAN9252_SPI_WRITE	0x2
+
+struct lan9252_read_cmd {
+	u8 cmd;
+	u8 addr_0;
+	u8 addr_1;
+} __packed;
+
+struct lan9252_write_cmd {
+	u8 cmd;
+	u8 addr_0;
+	u8 addr_1;
+	u32 data;
+} __packed;
+
+/* byte test register */
+#define LAN9252_BYTE_TEST		0x64
+#define   LAN9252_BYTE_TEST_VALUE	0x87654321
+
+/* hardware configuration register */
+#define LAN9252_HW_CFG		0x74
+#define   LAN9252_HW_CFG_READY	0x08000000
+
+/* EtherCAT CSR interface data register */
+#define LAN9252_ECAT_CSR_DATA	0x300
+
+/* EtherCAT CSR interface command register */
+#define LAN9252_ECAT_CSR_CMD	0x304
+#define   LAN9252_ECAT_CSR_BUSY	0x80000000
+#define   LAN9252_ECAT_CSR_READ	0x40000000
+
+/* EtherCAT slave controller MII register */
+#define LAN9252_ESC_MII			0x510
+#define   LAN9252_ESC_MII_BUSY		0x8000
+#define   LAN9252_ESC_MII_CMD_ERR	0x4000
+#define   LAN9252_ESC_MII_READ_ERR	0x2000
+#define   LAN9252_ESC_MII_ERR_MASK	(LAN9252_ESC_MII_CMD_ERR | \
+					 LAN9252_ESC_MII_READ_ERR)
+#define   LAN9252_ESC_MII_WRITE		0x0200
+#define   LAN9252_ESC_MII_READ		0x0100
+
+/* EtherCAT slave controller PHY address register */
+#define LAN9252_ESC_PHY_ADDR		0x512
+
+/* EtherCAT slave controller PHY register address register */
+#define LAN9252_ESC_PHY_REG_ADDR	0x513
+
+/* EtherCAT slave controller PHY data register */
+#define LAN9252_ESC_PHY_DATA		0x514
+
+/* EtherCAT slave controller PDI access state register */
+#define LAN9252_ESC_MII_PDI		0x517
+#define   LAN9252_ESC_MII_ACCESS_PDI	0x01
+#define   LAN9252_ESC_MII_ACCESS_ECAT	0x00
+
+/* PHY address */
+#define PHY_ADDRESS	2
+
+#define SPI_RETRY_COUNT		10
+#define SPI_WAIT_US		100
+#define SPI_CSR_WAIT_US		500
+
+static int lan9252_spi_read(struct spi_device *spi, u16 addr, u32 *data)
+{
+	struct lan9252_read_cmd cmd;
+
+	cmd.cmd = LAN9252_SPI_READ;
+	cmd.addr_0 = (addr >> 8) & 0xFF;
+	cmd.addr_1 = addr & 0xFF;
+
+	return spi_write_then_read(spi, (u8 *)&cmd,
+				   sizeof(struct lan9252_read_cmd),
+				   (u8 *)data, sizeof(u32));
+}
+
+static int lan9252_spi_write(struct spi_device *spi, u16 addr, u32 data)
+{
+	struct lan9252_write_cmd cmd;
+
+	cmd.cmd = LAN9252_SPI_WRITE;
+	cmd.addr_0 = (addr >> 8) & 0xFF;
+	cmd.addr_1 = addr & 0xFF;
+	cmd.data = data;
+
+	return spi_write(spi, (u8 *)&cmd, sizeof(struct lan9252_write_cmd));
+}
+
+static bool lan9252_init(struct spi_device *spi)
+{
+	u32 data;
+	int ret;
+
+	ret = lan9252_spi_read(spi, LAN9252_BYTE_TEST, &data);
+	if (ret || data != LAN9252_BYTE_TEST_VALUE)
+		return false;
+
+	ret = lan9252_spi_read(spi, LAN9252_HW_CFG, &data);
+	if (ret || !(data & LAN9252_HW_CFG_READY))
+		return false;
+
+	return true;
+}
+
+static u8 lan9252_esc_get_size(u16 addr)
+{
+	if (addr == LAN9252_ESC_MII || addr == LAN9252_ESC_PHY_DATA)
+		return 2;
+
+	return 1;
+}
+
+static int lan9252_esc_wait(struct spi_device *spi)
+{
+	ktime_t timeout = ktime_add_us(ktime_get(), SPI_WAIT_US);
+	u32 data;
+	int ret;
+
+	/* wait while CSR command is busy */
+	for (;;) {
+		ret = lan9252_spi_read(spi, LAN9252_ECAT_CSR_CMD, &data);
+		if (ret)
+			return ret;
+		if (!(data & LAN9252_ECAT_CSR_BUSY))
+			return 0;
+
+		if (ktime_compare(ktime_get(), timeout) > 0) {
+			ret = lan9252_spi_read(spi, LAN9252_ECAT_CSR_CMD, &data);
+			if (ret)
+				return ret;
+			break;
+		}
+	}
+
+	return (!(data & LAN9252_ECAT_CSR_BUSY)) ? 0 : -ETIMEDOUT;
+}
+
+static int lan9252_esc_read(struct spi_device *spi, u16 addr, u32 *data)
+{
+	u32 csr_cmd;
+	u8 size;
+	int ret;
+
+	size = lan9252_esc_get_size(addr);
+	csr_cmd = LAN9252_ECAT_CSR_BUSY | LAN9252_ECAT_CSR_READ;
+	csr_cmd |= (size << 16) | addr;
+	ret = lan9252_spi_write(spi, LAN9252_ECAT_CSR_CMD, csr_cmd);
+	if (ret)
+		return ret;
+
+	ret = lan9252_esc_wait(spi);
+	if (ret)
+		return ret;
+
+	ret = lan9252_spi_read(spi, LAN9252_ECAT_CSR_DATA, data);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int lan9252_esc_write(struct spi_device *spi, u16 addr, u32 data)
+{
+	u32 csr_cmd;
+	u8 size;
+	int ret;
+
+	ret = lan9252_spi_write(spi, LAN9252_ECAT_CSR_DATA, data);
+	if (ret)
+		return ret;
+
+	size = lan9252_esc_get_size(addr);
+	csr_cmd = LAN9252_ECAT_CSR_BUSY;
+	csr_cmd |= (size << 16) | addr;
+	ret = lan9252_spi_write(spi, LAN9252_ECAT_CSR_CMD, csr_cmd);
+	if (ret)
+		return ret;
+
+	ret = lan9252_esc_wait(spi);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int lan9252_access_mii(struct spi_device *spi, bool access)
+{
+	u32 data;
+
+	if (access)
+		data = LAN9252_ESC_MII_ACCESS_PDI;
+	else
+		data = LAN9252_ESC_MII_ACCESS_ECAT;
+
+	return lan9252_esc_write(spi, LAN9252_ESC_MII_PDI, data);
+}
+
+static int lan9252_mii_wait(struct spi_device *spi)
+{
+	ktime_t timeout = ktime_add_us(ktime_get(), SPI_CSR_WAIT_US);
+	u32 data;
+	int ret;
+
+	/* wait while MII control state machine is busy */
+	for (;;) {
+		ret = lan9252_esc_read(spi, LAN9252_ESC_MII, &data);
+		if (ret)
+			return ret;
+		if (data & LAN9252_ESC_MII_ERR_MASK)
+			return -EIO;
+		if (!(data & LAN9252_ESC_MII_BUSY))
+			return 0;
+
+		if (ktime_compare(ktime_get(), timeout) > 0) {
+			ret = lan9252_esc_read(spi, LAN9252_ESC_MII, &data);
+			if (ret)
+				return ret;
+			if (data & LAN9252_ESC_MII_ERR_MASK)
+				return -EIO;
+			break;
+		}
+	}
+
+	return (!(data & LAN9252_ESC_MII_BUSY)) ? 0 : -ETIMEDOUT;
+}
+
+static int lan9252_mii_read(struct spi_device *spi, u8 phy_addr, u8 reg_addr,
+			    u32 *data)
+{
+	int ret;
+
+	ret = lan9252_esc_write(spi, LAN9252_ESC_PHY_ADDR, phy_addr);
+	if (ret)
+		return ret;
+	ret = lan9252_esc_write(spi, LAN9252_ESC_PHY_REG_ADDR, reg_addr);
+	if (ret)
+		return ret;
+
+	ret = lan9252_esc_write(spi, LAN9252_ESC_MII, LAN9252_ESC_MII_READ);
+	if (ret)
+		return ret;
+
+	ret = lan9252_mii_wait(spi);
+	if (ret)
+		return ret;
+
+	return lan9252_esc_read(spi, LAN9252_ESC_PHY_DATA, data);
+}
+
+static int lan9252_mii_write(struct spi_device *spi, u8 phy_addr, u8 reg_addr,
+			     u32 data)
+{
+	int ret;
+
+	ret = lan9252_esc_write(spi, LAN9252_ESC_PHY_ADDR, phy_addr);
+	if (ret)
+		return ret;
+	ret = lan9252_esc_write(spi, LAN9252_ESC_PHY_REG_ADDR, reg_addr);
+	if (ret)
+		return ret;
+	ret = lan9252_esc_write(spi, LAN9252_ESC_PHY_DATA, data);
+	if (ret)
+		return ret;
+
+	ret = lan9252_esc_write(spi, LAN9252_ESC_MII, LAN9252_ESC_MII_WRITE);
+	if (ret)
+		return ret;
+
+	return lan9252_mii_wait(spi);
+}
+
+static int lan9252_probe(struct spi_device *spi)
+{
+	u32 data;
+	int retry = SPI_RETRY_COUNT;
+	int ret;
+
+	/* execute specified initialization sequence */
+	while (retry && !lan9252_init(spi))
+		retry--;
+	if (retry == 0) {
+		dev_err(&spi->dev,
+			"Can't initialize LAN9252 SPI communication!");
+		return -EIO;
+	}
+
+	/* enable access to MII management for PDI */
+	ret = lan9252_access_mii(spi, true);
+	if (ret) {
+		dev_err(&spi->dev, "Can't enable access to MII management!");
+		return ret;
+	}
+
+	/*
+	 * check PHY configuration and configure if necessary
+	 *	- full duplex
+	 *	- auto negotiation disabled
+	 *	- 100 Mbps
+	 */
+	ret = lan9252_mii_read(spi, PHY_ADDRESS, MII_BMCR, &data);
+	if (ret) {
+		dev_err(&spi->dev, "Can't read LAN9252 configuration!");
+		goto out;
+	}
+	if (!(data & BMCR_FULLDPLX) || (data & BMCR_ANENABLE) ||
+	    !(data & BMCR_SPEED100)) {
+		/*
+		 */
+		data &= ~(BMCR_ANENABLE);
+		data |= (BMCR_FULLDPLX | BMCR_SPEED100);
+		ret = lan9252_mii_write(spi, PHY_ADDRESS, MII_BMCR, data);
+		if (ret)
+			dev_err(&spi->dev,
+				"Can't write LAN9252 configuration!");
+	}
+
+	dev_info(&spi->dev, "LAN9252 PHY configuration");
+
+out:
+	/* disable access to MII management for PDI */
+	lan9252_access_mii(spi, false);
+
+	return ret;
+}
+
+static const struct spi_device_id lan9252_id[] = {
+	{ .name = "lan9252" },
+	{ }
+};
+MODULE_DEVICE_TABLE(spi, lan9252_id);
+
+static struct spi_driver lan9252_driver = {
+	.driver = {
+		.name	= "lan9252",
+	},
+	.probe		= lan9252_probe,
+	.id_table	= lan9252_id,
+};
+module_spi_driver(lan9252_driver);
+
+MODULE_AUTHOR("Petar Bojanic <boja@keba.com>");
+MODULE_AUTHOR("Gerhard Engleder <eg@keba.com>");
+MODULE_DESCRIPTION("KEBA LAN9252 driver");
+MODULE_LICENSE("GPL");