xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

fpga: dfl: support multiple opens on feature device node.

Browse Source 
Each DFL functional block, e.g. AFU (Accelerated Function Unit) and FME
(FPGA Management Engine), could implement more than one function within
its region, but current driver only allows one user application to access
it by exclusive open on device node. So this is not convenient and
flexible for userspace applications, as they have to combine lots of
different functions into one single application.

This patch removes the limitation here to allow multiple opens to each
feature device node for AFU and FME from userspace applications. If user
still needs exclusive access to these device node, O_EXCL flag must be
issued together with open.

Signed-off-by: Wu Hao <hao.wu@intel.com>
Signed-off-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Moritz Fischer <mdf@kernel.org>
This commit is contained in:
Xu Yilun
2019-11-18 13:20:41 +08:00
committed by Moritz Fischer
parent 8f3d9f3542
commit b6862193ca
4 changed files with 67 additions and 28 deletions
Download Patch File Download Diff File Expand all files Collapse all files

15
drivers/fpga/dfl.c
View File

@@ -1079,6 +1079,7 @@ static int __init dfl_fpga_init(void)
*/
int dfl_fpga_cdev_release_port(struct dfl_fpga_cdev *cdev, int port_id)
{
struct dfl_feature_platform_data *pdata;
struct platform_device *port_pdev;
int ret = -ENODEV;
@@ -1093,7 +1094,11 @@ int dfl_fpga_cdev_release_port(struct dfl_fpga_cdev *cdev, int port_id)
goto put_dev_exit;
}
ret = dfl_feature_dev_use_begin(dev_get_platdata(&port_pdev->dev));
pdata = dev_get_platdata(&port_pdev->dev);
mutex_lock(&pdata->lock);
ret = dfl_feature_dev_use_begin(pdata, true);
mutex_unlock(&pdata->lock);
if (ret)
goto put_dev_exit;
@@ -1120,6 +1125,7 @@ EXPORT_SYMBOL_GPL(dfl_fpga_cdev_release_port);
*/
int dfl_fpga_cdev_assign_port(struct dfl_fpga_cdev *cdev, int port_id)
{
struct dfl_feature_platform_data *pdata;
struct platform_device *port_pdev;
int ret = -ENODEV;
@@ -1138,7 +1144,12 @@ int dfl_fpga_cdev_assign_port(struct dfl_fpga_cdev *cdev, int port_id)
if (ret)
goto put_dev_exit;
dfl_feature_dev_use_end(dev_get_platdata(&port_pdev->dev));
pdata = dev_get_platdata(&port_pdev->dev);
mutex_lock(&pdata->lock);
dfl_feature_dev_use_end(pdata);
mutex_unlock(&pdata->lock);
cdev->released_port_num--;
put_dev_exit:
put_device(&port_pdev->dev);