Re: [PATCH v4 13/18] fpga: region: add register/unregister functions

From: Alan Tull
Date: Thu Sep 14 2017 - 16:04:38 EST

On Thu, Sep 14, 2017 at 4:56 AM, Wu Hao <hao.wu@xxxxxxxxx> wrote:
> On Thu, Sep 14, 2017 at 04:48:36AM +0800, Alan Tull wrote:
>> Another step in separating common code from device tree specific
>> code for FPGA regions.
>>
>> * add FPGA region register/unregister functions.
>> * add the register/unregister functions to the header
>> * use devm_kzalloc to alloc the region.
>> * add a method for getting bridges to the region struct
>> * add priv to the region struct
>> * use region->info in of_fpga_region_get_bridges
>>
>> Signed-off-by: Alan Tull <atull@xxxxxxxxxx>
>> ---
>> v2: split out from another patch
>> v3: use region->info, remove info param where applicable
>> v4: no change to this patch in this version of patchset
>> ---
>> drivers/fpga/fpga-region.c | 106 ++++++++++++++++++++++++---------------
>> include/linux/fpga/fpga-region.h | 7 +++
>> 2 files changed, 72 insertions(+), 41 deletions(-)
>>
>> diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
>> index 92ab216..ce57383 100644
>> --- a/drivers/fpga/fpga-region.c
>> +++ b/drivers/fpga/fpga-region.c
>> @@ -143,7 +143,6 @@ static struct fpga_manager *of_fpga_region_get_mgr(struct device_node *np)
>> /**
>> * of_fpga_region_get_bridges - create a list of bridges
>> * @region: FPGA region
>> - * @info: FPGA image info
>> *
>> * Create a list of bridges including the parent bridge and the bridges
>> * specified by "fpga-bridges" property. Note that the
>> @@ -156,11 +155,11 @@ static struct fpga_manager *of_fpga_region_get_mgr(struct device_node *np)
>> * Return 0 for success (even if there are no bridges specified)
>> * or -EBUSY if any of the bridges are in use.
>> */
>> -static int of_fpga_region_get_bridges(struct fpga_region *region,
>> - struct fpga_image_info *info)
>> +static int of_fpga_region_get_bridges(struct fpga_region *region)
>> {
>> struct device *dev = &region->dev;
>> struct device_node *region_np = dev->of_node;
>> + struct fpga_image_info *info = region->info;
>> struct device_node *br, *np, *parent_br = NULL;
>> int i, ret;
>>
>> @@ -192,7 +191,7 @@ static int of_fpga_region_get_bridges(struct fpga_region *region,
>> continue;
>>
>> /* If node is a bridge, get it and add to list */
>> - ret = of_fpga_bridge_get_to_list(br, region->info,
>> + ret = of_fpga_bridge_get_to_list(br, info,
>> &region->bridge_list);
>>
>> /* If any of the bridges are in use, give up */
>> @@ -229,10 +228,16 @@ int fpga_region_program_fpga(struct fpga_region *region)
>> goto err_put_region;
>> }
>>
>> - ret = of_fpga_region_get_bridges(region, info);
>> - if (ret) {
>> - dev_err(dev, "failed to get FPGA bridges\n");
>> - goto err_unlock_mgr;
>> + /*
>> + * In some cases, we already have a list of bridges in the
>> + * fpga region struct. Or we don't have any bridges.
>> + */
>> + if (region->get_bridges) {
>> + ret = region->get_bridges(region);
>> + if (ret) {
>> + dev_err(dev, "failed to get fpga region bridges\n");
>> + goto err_unlock_mgr;
>> + }
>> }
>>
>> ret = fpga_bridges_disable(&region->bridge_list);
>> @@ -259,7 +264,8 @@ int fpga_region_program_fpga(struct fpga_region *region)
>> return 0;
>>
>> err_put_br:
>> - fpga_bridges_put(&region->bridge_list);
>> + if (region->get_bridges)
>> + fpga_bridges_put(&region->bridge_list);
>> err_unlock_mgr:
>> fpga_mgr_unlock(region->mgr);
>> err_put_region:
>> @@ -522,39 +528,20 @@ static struct notifier_block fpga_region_of_nb = {
>> .notifier_call = of_fpga_region_notify,
>> };
>>
>> -static int of_fpga_region_probe(struct platform_device *pdev)
>> +int fpga_region_register(struct device *dev, struct fpga_region *region)
>> {
>> - struct device *dev = &pdev->dev;
>> - struct device_node *np = dev->of_node;
>> - struct fpga_region *region;
>> - struct fpga_manager *mgr;
>> int id, ret = 0;
>>
>> - mgr = of_fpga_region_get_mgr(np);
>> - if (IS_ERR(mgr))
>> - return -EPROBE_DEFER;
>> -
>> - region = kzalloc(sizeof(*region), GFP_KERNEL);
>> - if (!region) {
>> - ret = -ENOMEM;
>> - goto err_put_mgr;
>> - }
>> -
>> - region->mgr = mgr;
>> -
>> id = ida_simple_get(&fpga_region_ida, 0, 0, GFP_KERNEL);
>> - if (id < 0) {
>> - ret = id;
>> - goto err_kfree;
>> - }
>> + if (id < 0)
>> + return id;
>>
>> mutex_init(&region->mutex);
>> INIT_LIST_HEAD(&region->bridge_list);
>> -
>> device_initialize(&region->dev);
>> region->dev.class = fpga_region_class;
>> region->dev.parent = dev;
>> - region->dev.of_node = np;
>> + region->dev.of_node = dev->of_node;
>> region->dev.id = id;
>> dev_set_drvdata(dev, region);
>>
>> @@ -566,19 +553,58 @@ static int of_fpga_region_probe(struct platform_device *pdev)
>> if (ret)
>> goto err_remove;
>>
>> + return 0;
>> +
>> +err_remove:
>> + ida_simple_remove(&fpga_region_ida, id);
>> + return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(fpga_region_register);
>> +
>> +int fpga_region_unregister(struct fpga_region *region)
>> +{
>> + device_unregister(&region->dev);
>> +
>> + return 0;
>> +}
>> +EXPORT_SYMBOL_GPL(fpga_region_unregister);
>> +
>> +static int of_fpga_region_probe(struct platform_device *pdev)
>> +{
>> + struct device *dev = &pdev->dev;
>> + struct device_node *np = dev->of_node;
>> + struct fpga_region *region;
>> + struct fpga_manager *mgr;
>> + int ret;
>> +
>> + /* Find the FPGA mgr specified by region or parent region. */
>> + mgr = of_fpga_region_get_mgr(np);
>> + if (IS_ERR(mgr))
>> + return -EPROBE_DEFER;
>> +
>> + region = devm_kzalloc(dev, sizeof(*region), GFP_KERNEL);
>> + if (!region) {
>> + ret = -ENOMEM;
>> + goto eprobe_mgr_put;
>> + }
>> +
>> + region->mgr = mgr;
>> +
>> + /* Specify how to get bridges for this type of region. */
>> + region->get_bridges = of_fpga_region_get_bridges;
>> +
>> + ret = fpga_region_register(dev, region);
>> + if (ret)
>> + goto eprobe_mgr_put;
>> +
>> of_platform_populate(np, fpga_region_of_match, NULL, &region->dev);
>>
>> dev_info(dev, "FPGA Region probed\n");
>>
>> return 0;
>>
>> -err_remove:
>> - ida_simple_remove(&fpga_region_ida, id);
>> -err_kfree:
>> - kfree(region);
>> -err_put_mgr:
>> +eprobe_mgr_put:
>> fpga_mgr_put(mgr);
>> -
>> return ret;
>> }
>>
>> @@ -586,8 +612,7 @@ static int of_fpga_region_remove(struct platform_device *pdev)
>> {
>> struct fpga_region *region = platform_get_drvdata(pdev);
>>
>> - device_unregister(&region->dev);
>> - fpga_mgr_put(region->mgr);
>> + fpga_region_unregister(region);
>
> Hi Alan
>
> Do you think if we need to keep fpga_mgr_put(region->mgr) in this remove
> function? :)

Hi Hao,

Thanks for catching that! I'll add it back in.

Alan

>
> Thanks
> Hao