--- /dev/null
+/*
+ * Copyright (C) 2015 ST Microelectronics
+ *
+ * Author: Lee Jones <lee.jones@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/debugfs.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/mailbox_client.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/uaccess.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))
+
+static struct dentry *root_debugfs_dir;
+
+struct mbox_test_device {
+ struct device *dev;
+ void __iomem *mmio;
+ struct mbox_chan *tx_channel;
+ struct mbox_chan *rx_channel;
+ char *rx_buffer;
+ char *signal;
+ char *message;
+ spinlock_t lock;
+};
+
+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;
+ int ret;
+
+ 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 %d greater than max allowed %d\n",
+ count, MBOX_MAX_SIG_LEN);
+ return -EINVAL;
+ }
+
+ tdev->signal = kzalloc(MBOX_MAX_SIG_LEN, GFP_KERNEL);
+ if (!tdev->signal)
+ return -ENOMEM;
+
+ ret = copy_from_user(tdev->signal, userbuf, count);
+ if (ret) {
+ kfree(tdev->signal);
+ return -EFAULT;
+ }
+
+ return ret < 0 ? ret : count;
+}
+
+static const struct file_operations mbox_test_signal_ops = {
+ .write = mbox_test_signal_write,
+ .open = simple_open,
+ .llseek = generic_file_llseek,
+};
+
+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;
+ 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 %d greater than max allowed %d\n",
+ count, MBOX_MAX_MSG_LEN);
+ return -EINVAL;
+ }
+
+ tdev->message = kzalloc(MBOX_MAX_MSG_LEN, GFP_KERNEL);
+ if (!tdev->message)
+ return -ENOMEM;
+
+ 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->mmio && tdev->signal) {
+ print_hex_dump(KERN_INFO, "Client: Sending: Signal: ", DUMP_PREFIX_ADDRESS,
+ MBOX_BYTES_PER_LINE, 1, tdev->signal, MBOX_MAX_SIG_LEN, true);
+
+ data = tdev->signal;
+ } else
+ data = tdev->message;
+
+ print_hex_dump(KERN_INFO, "Client: Sending: Message: ", DUMP_PREFIX_ADDRESS,
+ MBOX_BYTES_PER_LINE, 1, tdev->message, MBOX_MAX_MSG_LEN, true);
+
+ 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);
+
+ return ret < 0 ? ret : count;
+}
+
+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;
+
+ touser = kzalloc(MBOX_HEXDUMP_MAX_LEN, 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 out;
+ }
+
+ if (tdev->rx_buffer[0] == '\0') {
+ ret = snprintf(touser, 9, "<EMPTY>\n");
+ ret = simple_read_from_buffer(userbuf, count, ppos,
+ touser, ret);
+ goto out;
+ }
+
+ 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);
+
+ spin_unlock_irqrestore(&tdev->lock, flags);
+
+ ret = simple_read_from_buffer(userbuf, count, ppos, touser, MBOX_HEXDUMP_MAX_LEN);
+out:
+ kfree(touser);
+ return ret;
+}
+
+static const struct file_operations mbox_test_message_ops = {
+ .write = mbox_test_message_write,
+ .read = mbox_test_message_read,
+ .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;
+
+ root_debugfs_dir = debugfs_create_dir("mailbox", NULL);
+ if (!root_debugfs_dir) {
+ dev_err(&pdev->dev, "Failed to create Mailbox debugfs\n");
+ return -EINVAL;
+ }
+
+ debugfs_create_file("message", 0600, root_debugfs_dir,
+ tdev, &mbox_test_message_ops);
+
+ debugfs_create_file("signal", 0200, 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->mmio) {
+ print_hex_dump(KERN_INFO, "Client: Received [MMIO]: ",
+ DUMP_PREFIX_ADDRESS, MBOX_BYTES_PER_LINE, 1,
+ tdev->mmio, MBOX_MAX_MSG_LEN, true);
+ memcpy(tdev->rx_buffer, tdev->mmio, MBOX_MAX_MSG_LEN);
+
+ } else if (message) {
+ print_hex_dump(KERN_INFO, "Client: Received [API]: ",
+ DUMP_PREFIX_ADDRESS, MBOX_BYTES_PER_LINE, 1,
+ message, MBOX_MAX_MSG_LEN, true);
+ memcpy(tdev->rx_buffer, message, MBOX_MAX_MSG_LEN);
+ }
+ spin_unlock_irqrestore(&tdev->lock, flags);
+}
+
+static void mbox_test_prepare_message(struct mbox_client *client, void *message)
+{
+ struct mbox_test_device *tdev = dev_get_drvdata(client->dev);
+
+ if (tdev->mmio) {
+ if (tdev->signal)
+ memcpy(tdev->mmio, tdev->message, MBOX_MAX_MSG_LEN);
+ else
+ memcpy(tdev->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 ERR_PTR(-ENOMEM);
+
+ 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 int mbox_test_probe(struct platform_device *pdev)
+{
+ struct mbox_test_device *tdev;
+ struct resource *res;
+ int ret;
+
+ tdev = devm_kzalloc(&pdev->dev, sizeof(*tdev), GFP_KERNEL);
+ if (!tdev)
+ return -ENOMEM;
+
+ /* It's okay for MMIO to be NULL */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ tdev->mmio = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(tdev->mmio))
+ tdev->mmio = NULL;
+
+ tdev->tx_channel = mbox_test_request_channel(pdev, "tx");
+ tdev->rx_channel = mbox_test_request_channel(pdev, "rx");
+
+ if (!tdev->tx_channel && !tdev->tx_channel)
+ return -EPROBE_DEFER;
+
+ tdev->dev = &pdev->dev;
+ platform_set_drvdata(pdev, tdev);
+
+ spin_lock_init(&tdev->lock);
+
+ if (tdev->rx_channel) {
+ tdev->rx_buffer = devm_kzalloc(&pdev->dev,
+ MBOX_MAX_MSG_LEN, GFP_KERNEL);
+ if (!tdev->rx_buffer)
+ return -ENOMEM;
+ }
+
+ ret = mbox_test_add_debugfs(pdev, tdev);
+ if (ret)
+ return ret;
+
+ dev_info(&pdev->dev, "Successfully registered\n");
+
+ return 0;
+}
+
+static int mbox_test_remove(struct platform_device *pdev)
+{
+ struct mbox_test_device *tdev = platform_get_drvdata(pdev);
+
+ debugfs_remove_recursive(root_debugfs_dir);
+
+ if (tdev->tx_channel)
+ mbox_free_channel(tdev->tx_channel);
+ if (tdev->rx_channel)
+ mbox_free_channel(tdev->rx_channel);
+
+ return 0;
+}
+
+static const struct of_device_id mbox_test_match[] = {
+ { .compatible = "mailbox_test" },
+ {},
+};
+
+static struct platform_driver mbox_test_driver = {
+ .driver = {
+ .name = "mailbox_sti_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");
projects / GitHub / LineageOS / android_kernel_motorola_exynos9610.git / commitdiff