Function pci_write

components/drivers/pci/procfs.c:145–218

}

static ssize_t pci_write(struct dfs_file *file, const void *buf, size_t count, off_t *ppos)
{
    off_t pos = *ppos;
    size_t res = count;
    rt_ubase_t pm_flags;
    struct proc_dentry *dentry = file->vnode->data;
    struct rt_pci_device *pdev = dentry->data;

    pci_pm_runtime_get(pdev, &pm_flags);

    if ((pos & 1) && count)
    {
        rt_uint8_t val;

        copy_from_user(&val, buf, sizeof(val));
        rt_pci_write_config_u8(pdev, pos, val);

        ++buf;
        ++pos;
        --count;
    }

    if ((pos & 3) && count > 2)
    {
        rt_le16_t val;

        copy_from_user(&val, buf, sizeof(val));
        rt_pci_write_config_u16(pdev, pos, rt_le16_to_cpu(val));

        buf += 2;
        pos += 2;
        count -= 2;
    }

    while (count >= 4)
    {
        rt_le32_t val;

        copy_from_user(&val, buf, sizeof(val));
        rt_pci_write_config_u32(pdev, pos, rt_le32_to_cpu(val));

        buf += 4;
        pos += 4;
        count -= 4;
    }

    if (count >= 2)
    {
        rt_le16_t val;

        copy_from_user(&val, buf, sizeof(val));
        rt_pci_write_config_u16(pdev, pos, rt_le16_to_cpu(val));

        buf += 2;
        pos += 2;
        count -= 2;
    }