uio: Add snapshot of MSM sharedmem driver
This is a snapshot of the MSM sharedmem driver as of msm-3.14
commit:
commit 149717c082aab81 ("uio: msm_sharedmem: Add custom mmap")
The following changes are included:
02d55287 uio: msm_sharedmem: Restrict debugfs write to root.
de961fc7 uio: msm_sharedmem: Return ENOMEM if the shared mem addr
is zero.
b974ce64 uio: msm_sharedmem: Add addtional information to debugfs
c46af547 uio: msm_sharedmem: Add support for dynamic shared memory
allocation
Change-Id: I49902f018bde1d59d41027b7e46268cc17231a3e
Signed-off-by: Nikhilesh Reddy <reddyn@codeaurora.org>
[riteshh@codeaurora.org: fixed trivial merge conflicts]
Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
diff --git a/drivers/uio/msm_sharedmem/msm_sharedmem.c b/drivers/uio/msm_sharedmem/msm_sharedmem.c
new file mode 100644
index 0000000..68f6211
--- /dev/null
+++ b/drivers/uio/msm_sharedmem/msm_sharedmem.c
@@ -0,0 +1,207 @@
+/* Copyright (c) 2013-2015, The Linux Foundation. All rights reserved.
+ *
+ * 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.
+ */
+
+#define DRIVER_NAME "msm_sharedmem"
+#define pr_fmt(fmt) DRIVER_NAME ": %s: " fmt, __func__
+
+#include <linux/uio_driver.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/dma-mapping.h>
+#include "sharedmem_qmi.h"
+
+#define CLIENT_ID_PROP "qcom,client-id"
+
+static int uio_get_mem_index(struct uio_info *info, struct vm_area_struct *vma)
+{
+ if (vma->vm_pgoff >= MAX_UIO_MAPS)
+ return -EINVAL;
+
+ if (info->mem[vma->vm_pgoff].size == 0)
+ return -EINVAL;
+
+ return (int)vma->vm_pgoff;
+}
+
+static int sharedmem_mmap(struct uio_info *info, struct vm_area_struct *vma)
+{
+ int result;
+ struct uio_mem *mem;
+ int mem_index = uio_get_mem_index(info, vma);
+
+ if (mem_index < 0) {
+ pr_err("mem_index is invalid errno %d\n", mem_index);
+ return mem_index;
+ }
+
+ mem = info->mem + mem_index;
+
+ if (vma->vm_end - vma->vm_start > mem->size) {
+ pr_err("vm_end[%lu] - vm_start[%lu] [%lu] > mem->size[%lu]\n",
+ vma->vm_end, vma->vm_start,
+ (vma->vm_end - vma->vm_start), mem->size);
+ return -EINVAL;
+ }
+ pr_debug("Attempting to setup mmap.\n");
+
+ vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
+
+ result = remap_pfn_range(vma,
+ vma->vm_start,
+ mem->addr >> PAGE_SHIFT,
+ vma->vm_end - vma->vm_start,
+ vma->vm_page_prot);
+ if (result != 0)
+ pr_err("mmap Failed with errno %d\n", result);
+ else
+ pr_debug("mmap success\n");
+
+ return result;
+}
+
+static int msm_sharedmem_probe(struct platform_device *pdev)
+{
+ int ret = 0;
+ struct uio_info *info = NULL;
+ struct resource *clnt_res = NULL;
+ u32 client_id = ((u32)~0U);
+ u32 shared_mem_size = 0;
+ void *shared_mem = NULL;
+ phys_addr_t shared_mem_pyhsical = 0;
+ bool is_addr_dynamic = false;
+ struct sharemem_qmi_entry qmi_entry;
+
+ /* Get the addresses from platform-data */
+ if (!pdev->dev.of_node) {
+ pr_err("Node not found\n");
+ ret = -ENODEV;
+ goto out;
+ }
+ clnt_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!clnt_res) {
+ pr_err("resource not found\n");
+ return -ENODEV;
+ }
+
+ ret = of_property_read_u32(pdev->dev.of_node, CLIENT_ID_PROP,
+ &client_id);
+ if (ret) {
+ client_id = ((u32)~0U);
+ pr_warn("qcom,client-id property not found\n");
+ }
+
+ info = devm_kzalloc(&pdev->dev, sizeof(struct uio_info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+
+ shared_mem_size = resource_size(clnt_res);
+ shared_mem_pyhsical = clnt_res->start;
+
+ if (shared_mem_size == 0) {
+ pr_err("Shared memory size is zero\n");
+ return -EINVAL;
+ }
+
+ if (shared_mem_pyhsical == 0) {
+ is_addr_dynamic = true;
+ shared_mem = dma_alloc_coherent(&pdev->dev, shared_mem_size,
+ &shared_mem_pyhsical, GFP_KERNEL);
+ if (shared_mem == NULL) {
+ pr_err("Shared mem alloc client=%s, size=%u\n",
+ clnt_res->name, shared_mem_size);
+ return -ENOMEM;
+ }
+ }
+
+ /* Setup device */
+ info->mmap = sharedmem_mmap; /* Custom mmap function. */
+ info->name = clnt_res->name;
+ info->version = "1.0";
+ info->mem[0].addr = shared_mem_pyhsical;
+ info->mem[0].size = shared_mem_size;
+ info->mem[0].memtype = UIO_MEM_PHYS;
+
+ ret = uio_register_device(&pdev->dev, info);
+ if (ret) {
+ pr_err("uio register failed ret=%d\n", ret);
+ goto out;
+ }
+ dev_set_drvdata(&pdev->dev, info);
+
+ qmi_entry.client_id = client_id;
+ qmi_entry.client_name = info->name;
+ qmi_entry.address = info->mem[0].addr;
+ qmi_entry.size = info->mem[0].size;
+ qmi_entry.is_addr_dynamic = is_addr_dynamic;
+
+ sharedmem_qmi_add_entry(&qmi_entry);
+ pr_info("Device created for client '%s'\n", clnt_res->name);
+out:
+ return ret;
+}
+
+static int msm_sharedmem_remove(struct platform_device *pdev)
+{
+ struct uio_info *info = dev_get_drvdata(&pdev->dev);
+
+ uio_unregister_device(info);
+
+ return 0;
+}
+
+static const struct of_device_id msm_sharedmem_of_match[] = {
+ {.compatible = "qcom,sharedmem-uio",},
+ {},
+};
+MODULE_DEVICE_TABLE(of, msm_sharedmem_of_match);
+
+static struct platform_driver msm_sharedmem_driver = {
+ .probe = msm_sharedmem_probe,
+ .remove = msm_sharedmem_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .owner = THIS_MODULE,
+ .of_match_table = msm_sharedmem_of_match,
+ },
+};
+
+
+static int __init msm_sharedmem_init(void)
+{
+ int result;
+
+ result = sharedmem_qmi_init();
+ if (result < 0) {
+ pr_err("sharedmem_qmi_init failed result = %d\n", result);
+ return result;
+ }
+
+ result = platform_driver_register(&msm_sharedmem_driver);
+ if (result != 0) {
+ pr_err("Platform driver registration failed\n");
+ return result;
+ }
+ return 0;
+}
+
+static void __exit msm_sharedmem_exit(void)
+{
+ platform_driver_unregister(&msm_sharedmem_driver);
+ sharedmem_qmi_exit();
+}
+
+module_init(msm_sharedmem_init);
+module_exit(msm_sharedmem_exit);
+
+MODULE_LICENSE("GPL v2");