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path: root/drivers/soc/qcom/rmtfs_mem.c
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Diffstat (limited to 'drivers/soc/qcom/rmtfs_mem.c')
-rw-r--r--drivers/soc/qcom/rmtfs_mem.c269
1 files changed, 269 insertions, 0 deletions
diff --git a/drivers/soc/qcom/rmtfs_mem.c b/drivers/soc/qcom/rmtfs_mem.c
new file mode 100644
index 000000000000..ce35ff748adf
--- /dev/null
+++ b/drivers/soc/qcom/rmtfs_mem.c
@@ -0,0 +1,269 @@
+/*
+ * Copyright (c) 2017 Linaro Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/cdev.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+#include <linux/qcom_scm.h>
+
+#define QCOM_RMTFS_MEM_DEV_MAX (MINORMASK + 1)
+
+static dev_t qcom_rmtfs_mem_major;
+
+struct qcom_rmtfs_mem {
+ struct device dev;
+ struct cdev cdev;
+
+ void *base;
+ phys_addr_t addr;
+ phys_addr_t size;
+
+ unsigned int client_id;
+};
+
+static ssize_t qcom_rmtfs_mem_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf);
+
+static DEVICE_ATTR(phys_addr, 0400, qcom_rmtfs_mem_show, NULL);
+static DEVICE_ATTR(size, 0400, qcom_rmtfs_mem_show, NULL);
+static DEVICE_ATTR(client_id, 0400, qcom_rmtfs_mem_show, NULL);
+
+static ssize_t qcom_rmtfs_mem_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct qcom_rmtfs_mem *rmtfs_mem = container_of(dev,
+ struct qcom_rmtfs_mem,
+ dev);
+
+ if (attr == &dev_attr_phys_addr)
+ return sprintf(buf, "%pa\n", &rmtfs_mem->addr);
+ if (attr == &dev_attr_size)
+ return sprintf(buf, "%pa\n", &rmtfs_mem->size);
+ if (attr == &dev_attr_client_id)
+ return sprintf(buf, "%d\n", rmtfs_mem->client_id);
+
+ return -EINVAL;
+}
+
+static struct attribute *qcom_rmtfs_mem_attrs[] = {
+ &dev_attr_phys_addr.attr,
+ &dev_attr_size.attr,
+ &dev_attr_client_id.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(qcom_rmtfs_mem);
+
+static int qcom_rmtfs_mem_open(struct inode *inode, struct file *filp)
+{
+ struct qcom_rmtfs_mem *rmtfs_mem = container_of(inode->i_cdev,
+ struct qcom_rmtfs_mem,
+ cdev);
+
+ get_device(&rmtfs_mem->dev);
+ filp->private_data = rmtfs_mem;
+
+ return 0;
+}
+static ssize_t qcom_rmtfs_mem_read(struct file *filp,
+ char __user *buf, size_t count, loff_t *f_pos)
+{
+ struct qcom_rmtfs_mem *rmtfs_mem = filp->private_data;
+
+ if (*f_pos >= rmtfs_mem->size)
+ return 0;
+
+ if (*f_pos + count >= rmtfs_mem->size)
+ count = rmtfs_mem->size - *f_pos;
+
+ if (copy_to_user(buf, rmtfs_mem->base + *f_pos, count))
+ return -EFAULT;
+
+ *f_pos += count;
+ return count;
+}
+
+static ssize_t qcom_rmtfs_mem_write(struct file *filp,
+ const char __user *buf, size_t count,
+ loff_t *f_pos)
+{
+ struct qcom_rmtfs_mem *rmtfs_mem = filp->private_data;
+
+ if (*f_pos >= rmtfs_mem->size)
+ return 0;
+
+ if (*f_pos + count >= rmtfs_mem->size)
+ count = rmtfs_mem->size - *f_pos;
+
+ if (copy_from_user(rmtfs_mem->base + *f_pos, buf, count))
+ return -EFAULT;
+
+ *f_pos += count;
+ return count;
+}
+
+static int qcom_rmtfs_mem_release(struct inode *inode, struct file *filp)
+{
+ struct qcom_rmtfs_mem *rmtfs_mem = filp->private_data;
+
+ put_device(&rmtfs_mem->dev);
+
+ return 0;
+}
+
+static const struct file_operations qcom_rmtfs_mem_fops = {
+ .owner = THIS_MODULE,
+ .open = qcom_rmtfs_mem_open,
+ .read = qcom_rmtfs_mem_read,
+ .write = qcom_rmtfs_mem_write,
+ .release = qcom_rmtfs_mem_release,
+ .llseek = default_llseek,
+};
+
+static void qcom_rmtfs_mem_release_device(struct device *dev)
+{
+ struct qcom_rmtfs_mem *rmtfs_mem = container_of(dev,
+ struct qcom_rmtfs_mem,
+ dev);
+
+ kfree(rmtfs_mem);
+}
+
+static int qcom_rmtfs_mem_probe(struct platform_device *pdev)
+{
+ struct device_node *node = pdev->dev.of_node;
+ struct reserved_mem *rmem;
+ struct qcom_rmtfs_mem *rmtfs_mem;
+ u32 client_id;
+ int ret;
+
+ rmem = of_reserved_mem_lookup(node);
+ if (!rmem) {
+ dev_err(&pdev->dev, "failed to acquire memory region\n");
+ return -EINVAL;
+ }
+
+ ret = of_property_read_u32(node, "qcom,client-id", &client_id);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to parse \"qcom,client-id\"\n");
+ return ret;
+
+ }
+
+ rmtfs_mem = kzalloc(sizeof(*rmtfs_mem), GFP_KERNEL);
+ if (!rmtfs_mem)
+ return -ENOMEM;
+
+ rmtfs_mem->addr = rmem->base;
+ rmtfs_mem->client_id = client_id;
+ rmtfs_mem->size = rmem->size;
+
+ device_initialize(&rmtfs_mem->dev);
+ rmtfs_mem->dev.parent = &pdev->dev;
+ rmtfs_mem->dev.groups = qcom_rmtfs_mem_groups;
+
+ rmtfs_mem->base = devm_memremap(&rmtfs_mem->dev, rmtfs_mem->addr,
+ rmtfs_mem->size, MEMREMAP_WC);
+ if (IS_ERR(rmtfs_mem->base)) {
+ dev_err(&pdev->dev, "failed to remap rmtfs_mem region\n");
+ ret = PTR_ERR(rmtfs_mem->base);
+ goto put_device;
+ }
+
+ cdev_init(&rmtfs_mem->cdev, &qcom_rmtfs_mem_fops);
+ rmtfs_mem->cdev.owner = THIS_MODULE;
+
+ dev_set_name(&rmtfs_mem->dev, "qcom_rmtfs_mem%d", client_id);
+ rmtfs_mem->dev.id = client_id;
+ rmtfs_mem->dev.devt = MKDEV(MAJOR(qcom_rmtfs_mem_major), client_id);
+
+ ret = cdev_device_add(&rmtfs_mem->cdev, &rmtfs_mem->dev);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to add cdev: %d\n", ret);
+ goto put_device;
+ }
+
+ rmtfs_mem->dev.release = qcom_rmtfs_mem_release_device;
+
+ dev_set_drvdata(&pdev->dev, rmtfs_mem);
+
+ return 0;
+
+put_device:
+ put_device(&rmtfs_mem->dev);
+
+ return ret;
+}
+
+static int qcom_rmtfs_mem_remove(struct platform_device *pdev)
+{
+ struct qcom_rmtfs_mem *rmtfs_mem = dev_get_drvdata(&pdev->dev);
+
+ cdev_device_del(&rmtfs_mem->cdev, &rmtfs_mem->dev);
+ put_device(&rmtfs_mem->dev);
+
+ return 0;
+}
+
+static const struct of_device_id qcom_rmtfs_mem_of_match[] = {
+ { .compatible = "qcom,rmtfs-mem" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, qcom_rmtfs_mem_of_match);
+
+static struct platform_driver qcom_rmtfs_mem_driver = {
+ .probe = qcom_rmtfs_mem_probe,
+ .remove = qcom_rmtfs_mem_remove,
+ .driver = {
+ .name = "qcom_rmtfs_mem",
+ .of_match_table = qcom_rmtfs_mem_of_match,
+ },
+};
+
+static int qcom_rmtfs_mem_init(void)
+{
+ int ret;
+
+ ret = alloc_chrdev_region(&qcom_rmtfs_mem_major, 0,
+ QCOM_RMTFS_MEM_DEV_MAX, "qcom_rmtfs_mem");
+ if (ret < 0) {
+ pr_err("qcom_rmtfs_mem: failed to allocate char dev region\n");
+ return ret;
+ }
+
+ ret = platform_driver_register(&qcom_rmtfs_mem_driver);
+ if (ret < 0) {
+ pr_err("qcom_rmtfs_mem: failed to register rmtfs_mem driver\n");
+ unregister_chrdev_region(qcom_rmtfs_mem_major,
+ QCOM_RMTFS_MEM_DEV_MAX);
+ }
+
+ return ret;
+}
+module_init(qcom_rmtfs_mem_init);
+
+static void qcom_rmtfs_mem_exit(void)
+{
+ platform_driver_unregister(&qcom_rmtfs_mem_driver);
+ unregister_chrdev_region(qcom_rmtfs_mem_major, QCOM_RMTFS_MEM_DEV_MAX);
+}
+module_exit(qcom_rmtfs_mem_exit);