Re: [PATCH v3 06/21] fpga: dfl: adds fpga_cdev_find_port
From: Alan Tull <atull@kernel.org>
Date: 2018-02-05 22:09:02
Also in:
linux-fpga, lkml
On Mon, Nov 27, 2017 at 12:42 AM, Wu Hao [off-list ref] wrote: Hi Hao, A couple comments below.
For feature devices, e.g FPGA Management Engine (FME),
The first use I see of this function in this patchset is the FME PR, not the FME, or am I misunderstanding?
it may require fpga_cdev_find_port function to find dedicate port for further actions, so export this function from feature device driver module.
I understand the need for this function, but I'm having a hard time following this explanation here. Suggestion: "For feature devices, we need a method to find the port dedicated to the device. Add a function fpga_cdev_find_port to do that"
quoted hunk ↗ jump to hunk
Signed-off-by: Tim Whisonant <redacted> Signed-off-by: Enno Luebbers <redacted> Signed-off-by: Shiva Rao <redacted> Signed-off-by: Christopher Rauer <redacted> Signed-off-by: Xiao Guangrong <redacted> Signed-off-by: Wu Hao <redacted> ---- v3: s/fpga_for_each_port/fpga_cdev_find_port/ move fpga_cdev_find_port to fpga-dfl module. --- drivers/fpga/fpga-dfl.c | 27 +++++++++++++++++++++++++++ drivers/fpga/fpga-dfl.h | 16 ++++++++++++++++ 2 files changed, 43 insertions(+)diff --git a/drivers/fpga/fpga-dfl.c b/drivers/fpga/fpga-dfl.c index 9294c0a..ce03b17 100644 --- a/drivers/fpga/fpga-dfl.c +++ b/drivers/fpga/fpga-dfl.c@@ -873,6 +873,33 @@ void fpga_remove_feature_devs(struct fpga_cdev *cdev) } EXPORT_SYMBOL_GPL(fpga_remove_feature_devs); +/** + * __fpga_cdev_find_port - find a port under given container device + * @cdev: container device + * @data: data passed to match function + * @match: match function used to find specific port from the port device list + * + * Find a port device under container device. This function needs to be + * invoked with lock held. + */ +struct platform_device * +__fpga_cdev_find_port(struct fpga_cdev *cdev, void *data, + int (*match)(struct platform_device *, void *)) +{ + struct feature_platform_data *pdata; + struct platform_device *port_dev; + + list_for_each_entry(pdata, &cdev->port_dev_list, node) { + port_dev = pdata->dev; + + if (match(port_dev, data) && get_device(&port_dev->dev)) + return port_dev;
The caller will need to put the port_dev->dev. Please document that in the function header. I mentioned that in v2. Alan