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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/mailbox/mailbox-test.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/mailbox/mailbox-test.c')
-rw-r--r--drivers/mailbox/mailbox-test.c463
1 files changed, 463 insertions, 0 deletions
diff --git a/drivers/mailbox/mailbox-test.c b/drivers/mailbox/mailbox-test.c
new file mode 100644
index 000000000..7b6ef033e
--- /dev/null
+++ b/drivers/mailbox/mailbox-test.c
@@ -0,0 +1,463 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2015 ST Microelectronics
+ *
+ * Author: Lee Jones <lee.jones@linaro.org>
+ */
+
+#include <linux/debugfs.h>
+#include <linux/err.h>
+#include <linux/fs.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mailbox_client.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/poll.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/uaccess.h>
+#include <linux/sched/signal.h>
+
+#define MBOX_MAX_SIG_LEN 8
+#define MBOX_MAX_MSG_LEN 128
+#define MBOX_BYTES_PER_LINE 16
+#define MBOX_HEXDUMP_LINE_LEN ((MBOX_BYTES_PER_LINE * 4) + 2)
+#define MBOX_HEXDUMP_MAX_LEN (MBOX_HEXDUMP_LINE_LEN * \
+ (MBOX_MAX_MSG_LEN / MBOX_BYTES_PER_LINE))
+
+struct mbox_test_device {
+ struct device *dev;
+ void __iomem *tx_mmio;
+ void __iomem *rx_mmio;
+ struct mbox_chan *tx_channel;
+ struct mbox_chan *rx_channel;
+ char *rx_buffer;
+ char *signal;
+ char *message;
+ spinlock_t lock;
+ struct mutex mutex;
+ wait_queue_head_t waitq;
+ bool data_ready;
+ struct fasync_struct *async_queue;
+ struct dentry *root_debugfs_dir;
+};
+
+static ssize_t mbox_test_signal_write(struct file *filp,
+ const char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ struct mbox_test_device *tdev = filp->private_data;
+
+ if (!tdev->tx_channel) {
+ dev_err(tdev->dev, "Channel cannot do Tx\n");
+ return -EINVAL;
+ }
+
+ if (count > MBOX_MAX_SIG_LEN) {
+ dev_err(tdev->dev,
+ "Signal length %zd greater than max allowed %d\n",
+ count, MBOX_MAX_SIG_LEN);
+ return -EINVAL;
+ }
+
+ /* Only allocate memory if we need to */
+ if (!tdev->signal) {
+ tdev->signal = kzalloc(MBOX_MAX_SIG_LEN, GFP_KERNEL);
+ if (!tdev->signal)
+ return -ENOMEM;
+ }
+
+ if (copy_from_user(tdev->signal, userbuf, count)) {
+ kfree(tdev->signal);
+ tdev->signal = NULL;
+ return -EFAULT;
+ }
+
+ return count;
+}
+
+static const struct file_operations mbox_test_signal_ops = {
+ .write = mbox_test_signal_write,
+ .open = simple_open,
+ .llseek = generic_file_llseek,
+};
+
+static int mbox_test_message_fasync(int fd, struct file *filp, int on)
+{
+ struct mbox_test_device *tdev = filp->private_data;
+
+ return fasync_helper(fd, filp, on, &tdev->async_queue);
+}
+
+static ssize_t mbox_test_message_write(struct file *filp,
+ const char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ struct mbox_test_device *tdev = filp->private_data;
+ char *message;
+ void *data;
+ int ret;
+
+ if (!tdev->tx_channel) {
+ dev_err(tdev->dev, "Channel cannot do Tx\n");
+ return -EINVAL;
+ }
+
+ if (count > MBOX_MAX_MSG_LEN) {
+ dev_err(tdev->dev,
+ "Message length %zd greater than max allowed %d\n",
+ count, MBOX_MAX_MSG_LEN);
+ return -EINVAL;
+ }
+
+ message = kzalloc(MBOX_MAX_MSG_LEN, GFP_KERNEL);
+ if (!message)
+ return -ENOMEM;
+
+ mutex_lock(&tdev->mutex);
+
+ tdev->message = message;
+ ret = copy_from_user(tdev->message, userbuf, count);
+ if (ret) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ /*
+ * A separate signal is only of use if there is
+ * MMIO to subsequently pass the message through
+ */
+ if (tdev->tx_mmio && tdev->signal) {
+ print_hex_dump_bytes("Client: Sending: Signal: ", DUMP_PREFIX_ADDRESS,
+ tdev->signal, MBOX_MAX_SIG_LEN);
+
+ data = tdev->signal;
+ } else
+ data = tdev->message;
+
+ print_hex_dump_bytes("Client: Sending: Message: ", DUMP_PREFIX_ADDRESS,
+ tdev->message, MBOX_MAX_MSG_LEN);
+
+ ret = mbox_send_message(tdev->tx_channel, data);
+ if (ret < 0)
+ dev_err(tdev->dev, "Failed to send message via mailbox\n");
+
+out:
+ kfree(tdev->signal);
+ kfree(tdev->message);
+ tdev->signal = NULL;
+
+ mutex_unlock(&tdev->mutex);
+
+ return ret < 0 ? ret : count;
+}
+
+static bool mbox_test_message_data_ready(struct mbox_test_device *tdev)
+{
+ bool data_ready;
+ unsigned long flags;
+
+ spin_lock_irqsave(&tdev->lock, flags);
+ data_ready = tdev->data_ready;
+ spin_unlock_irqrestore(&tdev->lock, flags);
+
+ return data_ready;
+}
+
+static ssize_t mbox_test_message_read(struct file *filp, char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ struct mbox_test_device *tdev = filp->private_data;
+ unsigned long flags;
+ char *touser, *ptr;
+ int l = 0;
+ int ret;
+
+ DECLARE_WAITQUEUE(wait, current);
+
+ touser = kzalloc(MBOX_HEXDUMP_MAX_LEN + 1, GFP_KERNEL);
+ if (!touser)
+ return -ENOMEM;
+
+ if (!tdev->rx_channel) {
+ ret = snprintf(touser, 20, "<NO RX CAPABILITY>\n");
+ ret = simple_read_from_buffer(userbuf, count, ppos,
+ touser, ret);
+ goto kfree_err;
+ }
+
+ add_wait_queue(&tdev->waitq, &wait);
+
+ do {
+ __set_current_state(TASK_INTERRUPTIBLE);
+
+ if (mbox_test_message_data_ready(tdev))
+ break;
+
+ if (filp->f_flags & O_NONBLOCK) {
+ ret = -EAGAIN;
+ goto waitq_err;
+ }
+
+ if (signal_pending(current)) {
+ ret = -ERESTARTSYS;
+ goto waitq_err;
+ }
+ schedule();
+
+ } while (1);
+
+ spin_lock_irqsave(&tdev->lock, flags);
+
+ ptr = tdev->rx_buffer;
+ while (l < MBOX_HEXDUMP_MAX_LEN) {
+ hex_dump_to_buffer(ptr,
+ MBOX_BYTES_PER_LINE,
+ MBOX_BYTES_PER_LINE, 1, touser + l,
+ MBOX_HEXDUMP_LINE_LEN, true);
+
+ ptr += MBOX_BYTES_PER_LINE;
+ l += MBOX_HEXDUMP_LINE_LEN;
+ *(touser + (l - 1)) = '\n';
+ }
+ *(touser + l) = '\0';
+
+ memset(tdev->rx_buffer, 0, MBOX_MAX_MSG_LEN);
+ tdev->data_ready = false;
+
+ spin_unlock_irqrestore(&tdev->lock, flags);
+
+ ret = simple_read_from_buffer(userbuf, count, ppos, touser, MBOX_HEXDUMP_MAX_LEN);
+waitq_err:
+ __set_current_state(TASK_RUNNING);
+ remove_wait_queue(&tdev->waitq, &wait);
+kfree_err:
+ kfree(touser);
+ return ret;
+}
+
+static __poll_t
+mbox_test_message_poll(struct file *filp, struct poll_table_struct *wait)
+{
+ struct mbox_test_device *tdev = filp->private_data;
+
+ poll_wait(filp, &tdev->waitq, wait);
+
+ if (mbox_test_message_data_ready(tdev))
+ return EPOLLIN | EPOLLRDNORM;
+ return 0;
+}
+
+static const struct file_operations mbox_test_message_ops = {
+ .write = mbox_test_message_write,
+ .read = mbox_test_message_read,
+ .fasync = mbox_test_message_fasync,
+ .poll = mbox_test_message_poll,
+ .open = simple_open,
+ .llseek = generic_file_llseek,
+};
+
+static int mbox_test_add_debugfs(struct platform_device *pdev,
+ struct mbox_test_device *tdev)
+{
+ if (!debugfs_initialized())
+ return 0;
+
+ tdev->root_debugfs_dir = debugfs_create_dir(dev_name(&pdev->dev), NULL);
+ if (IS_ERR(tdev->root_debugfs_dir)) {
+ dev_err(&pdev->dev, "Failed to create Mailbox debugfs\n");
+ return -EINVAL;
+ }
+
+ debugfs_create_file("message", 0600, tdev->root_debugfs_dir,
+ tdev, &mbox_test_message_ops);
+
+ debugfs_create_file("signal", 0200, tdev->root_debugfs_dir,
+ tdev, &mbox_test_signal_ops);
+
+ return 0;
+}
+
+static void mbox_test_receive_message(struct mbox_client *client, void *message)
+{
+ struct mbox_test_device *tdev = dev_get_drvdata(client->dev);
+ unsigned long flags;
+
+ spin_lock_irqsave(&tdev->lock, flags);
+ if (tdev->rx_mmio) {
+ memcpy_fromio(tdev->rx_buffer, tdev->rx_mmio, MBOX_MAX_MSG_LEN);
+ print_hex_dump_bytes("Client: Received [MMIO]: ", DUMP_PREFIX_ADDRESS,
+ tdev->rx_buffer, MBOX_MAX_MSG_LEN);
+ } else if (message) {
+ print_hex_dump_bytes("Client: Received [API]: ", DUMP_PREFIX_ADDRESS,
+ message, MBOX_MAX_MSG_LEN);
+ memcpy(tdev->rx_buffer, message, MBOX_MAX_MSG_LEN);
+ }
+ tdev->data_ready = true;
+ spin_unlock_irqrestore(&tdev->lock, flags);
+
+ wake_up_interruptible(&tdev->waitq);
+
+ kill_fasync(&tdev->async_queue, SIGIO, POLL_IN);
+}
+
+static void mbox_test_prepare_message(struct mbox_client *client, void *message)
+{
+ struct mbox_test_device *tdev = dev_get_drvdata(client->dev);
+
+ if (tdev->tx_mmio) {
+ if (tdev->signal)
+ memcpy_toio(tdev->tx_mmio, tdev->message, MBOX_MAX_MSG_LEN);
+ else
+ memcpy_toio(tdev->tx_mmio, message, MBOX_MAX_MSG_LEN);
+ }
+}
+
+static void mbox_test_message_sent(struct mbox_client *client,
+ void *message, int r)
+{
+ if (r)
+ dev_warn(client->dev,
+ "Client: Message could not be sent: %d\n", r);
+ else
+ dev_info(client->dev,
+ "Client: Message sent\n");
+}
+
+static struct mbox_chan *
+mbox_test_request_channel(struct platform_device *pdev, const char *name)
+{
+ struct mbox_client *client;
+ struct mbox_chan *channel;
+
+ client = devm_kzalloc(&pdev->dev, sizeof(*client), GFP_KERNEL);
+ if (!client)
+ return NULL;
+
+ client->dev = &pdev->dev;
+ client->rx_callback = mbox_test_receive_message;
+ client->tx_prepare = mbox_test_prepare_message;
+ client->tx_done = mbox_test_message_sent;
+ client->tx_block = true;
+ client->knows_txdone = false;
+ client->tx_tout = 500;
+
+ channel = mbox_request_channel_byname(client, name);
+ if (IS_ERR(channel)) {
+ dev_warn(&pdev->dev, "Failed to request %s channel\n", name);
+ return NULL;
+ }
+
+ return channel;
+}
+
+static void __iomem *mbox_test_ioremap(struct platform_device *pdev, unsigned int res_num)
+{
+ struct resource *res;
+ void __iomem *mmio;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, res_num);
+ if (!res)
+ return NULL;
+
+ mmio = devm_ioremap_resource(&pdev->dev, res);
+ if (PTR_ERR(mmio) == -EBUSY) {
+ dev_info(&pdev->dev, "trying workaround with plain ioremap\n");
+ return devm_ioremap(&pdev->dev, res->start, resource_size(res));
+ }
+
+ return IS_ERR(mmio) ? NULL : mmio;
+}
+
+static int mbox_test_probe(struct platform_device *pdev)
+{
+ struct mbox_test_device *tdev;
+ int ret;
+
+ tdev = devm_kzalloc(&pdev->dev, sizeof(*tdev), GFP_KERNEL);
+ if (!tdev)
+ return -ENOMEM;
+
+ tdev->dev = &pdev->dev;
+ spin_lock_init(&tdev->lock);
+ mutex_init(&tdev->mutex);
+ init_waitqueue_head(&tdev->waitq);
+ platform_set_drvdata(pdev, tdev);
+
+ /* It's okay for MMIO to be NULL */
+ tdev->tx_mmio = mbox_test_ioremap(pdev, 0);
+
+ /* If specified, second reg entry is Rx MMIO */
+ tdev->rx_mmio = mbox_test_ioremap(pdev, 1);
+ if (!tdev->rx_mmio)
+ tdev->rx_mmio = tdev->tx_mmio;
+
+ tdev->tx_channel = mbox_test_request_channel(pdev, "tx");
+ tdev->rx_channel = mbox_test_request_channel(pdev, "rx");
+
+ if (!tdev->tx_channel && !tdev->rx_channel)
+ return -EPROBE_DEFER;
+
+ /* If Rx is not specified but has Rx MMIO, then Rx = Tx */
+ if (!tdev->rx_channel && (tdev->rx_mmio != tdev->tx_mmio))
+ tdev->rx_channel = tdev->tx_channel;
+
+ if (tdev->rx_channel) {
+ tdev->rx_buffer = devm_kzalloc(&pdev->dev,
+ MBOX_MAX_MSG_LEN, GFP_KERNEL);
+ if (!tdev->rx_buffer) {
+ ret = -ENOMEM;
+ goto err_free_chans;
+ }
+ }
+
+ ret = mbox_test_add_debugfs(pdev, tdev);
+ if (ret)
+ goto err_free_chans;
+
+ dev_info(&pdev->dev, "Successfully registered\n");
+
+ return 0;
+
+err_free_chans:
+ if (tdev->tx_channel)
+ mbox_free_channel(tdev->tx_channel);
+ if (tdev->rx_channel && tdev->rx_channel != tdev->tx_channel)
+ mbox_free_channel(tdev->rx_channel);
+ return ret;
+}
+
+static void mbox_test_remove(struct platform_device *pdev)
+{
+ struct mbox_test_device *tdev = platform_get_drvdata(pdev);
+
+ debugfs_remove_recursive(tdev->root_debugfs_dir);
+
+ if (tdev->tx_channel)
+ mbox_free_channel(tdev->tx_channel);
+ if (tdev->rx_channel && tdev->rx_channel != tdev->tx_channel)
+ mbox_free_channel(tdev->rx_channel);
+}
+
+static const struct of_device_id mbox_test_match[] = {
+ { .compatible = "mailbox-test" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, mbox_test_match);
+
+static struct platform_driver mbox_test_driver = {
+ .driver = {
+ .name = "mailbox_test",
+ .of_match_table = mbox_test_match,
+ },
+ .probe = mbox_test_probe,
+ .remove = mbox_test_remove,
+};
+module_platform_driver(mbox_test_driver);
+
+MODULE_DESCRIPTION("Generic Mailbox Testing Facility");
+MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org");
+MODULE_LICENSE("GPL v2");