On Tue, May 1, 2018 at 9:50 PM, Wu Hao <hao.wu@xxxxxxxxx> wrote: Hi Hao, > For feature devices drivers, both the FPGA Management Engine (FME) and > Accelerated Function Unit (AFU) driver need to expose user interfaces via > the device file, for example, mmap and ioctls. > > This patch adds chardev support in the dfl driver for feature devices, > FME and AFU. It reserves the chardev regions for FME and AFU, and provide > interfaces for FME and AFU driver to register their device file operations. > > Signed-off-by: Tim Whisonant <tim.whisonant@xxxxxxxxx> > Signed-off-by: Enno Luebbers <enno.luebbers@xxxxxxxxx> > Signed-off-by: Shiva Rao <shiva.rao@xxxxxxxxx> > Signed-off-by: Christopher Rauer <christopher.rauer@xxxxxxxxx> > Signed-off-by: Zhang Yi <yi.z.zhang@xxxxxxxxx> > Signed-off-by: Xiao Guangrong <guangrong.xiao@xxxxxxxxxxxxxxx> > Signed-off-by: Wu Hao <hao.wu@xxxxxxxxx> > --- > v2: rebased > v3: move chardev support to fpga-dfl framework > v4: rebase, and add more comments in code. > v5: rebase, and add dfl_ prefix to APIs and data structures. > --- > drivers/fpga/dfl.c | 104 ++++++++++++++++++++++++++++++++++++++++++++++++++++- > drivers/fpga/dfl.h | 14 ++++++++ > 2 files changed, 117 insertions(+), 1 deletion(-) > > diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c > index c1462e9..18aba02 100644 > --- a/drivers/fpga/dfl.c > +++ b/drivers/fpga/dfl.c > @@ -74,6 +74,96 @@ static enum dfl_id_type feature_dev_id_type(struct platform_device *pdev) > return DFL_ID_MAX; > } > > +struct dfl_chardev_info { > + const char *name; > + dev_t devt; > +}; > + > +/* indexed by enum dfl_fpga_devt_type */ > +struct dfl_chardev_info dfl_chrdevs[] = { > + {.name = DFL_FPGA_FEATURE_DEV_FME}, /* DFL_FPGA_DEVT_FME */ > + {.name = DFL_FPGA_FEATURE_DEV_PORT}, /* DFL_FPGA_DEVT_AFU */ > +}; If this were added in the initial dfl.c patch, it could be used by build_info_create_dev to get the name. > + > +static void dfl_chardev_uinit(void) > +{ > + int i; > + > + for (i = 0; i < DFL_FPGA_DEVT_MAX; i++) > + if (MAJOR(dfl_chrdevs[i].devt)) { > + unregister_chrdev_region(dfl_chrdevs[i].devt, > + MINORMASK); > + dfl_chrdevs[i].devt = MKDEV(0, 0); > + } > +} > + > +static int dfl_chardev_init(void) > +{ > + int i, ret; > + > + for (i = 0; i < DFL_FPGA_DEVT_MAX; i++) { > + ret = alloc_chrdev_region(&dfl_chrdevs[i].devt, 0, MINORMASK, > + dfl_chrdevs[i].name); > + if (ret) > + goto exit; > + } > + > + return 0; > + > +exit: > + dfl_chardev_uinit(); > + return ret; > +} > + > +static dev_t dfl_get_devt(enum dfl_fpga_devt_type type, int id) > +{ > + WARN_ON(type >= DFL_FPGA_DEVT_MAX); > + > + return MKDEV(MAJOR(dfl_chrdevs[type].devt), id); > +} > + > +/** > + * dfl_fpga_register_dev_ops - register cdev ops for feature dev > + * > + * @pdev: feature dev. > + * @fops: file operations for feature dev's cdev. > + * @owner: owning module/driver. > + * > + * Return: 0 on success, negative error code otherwise. > + */ > +int dfl_fpga_register_dev_ops(struct platform_device *pdev, > + const struct file_operations *fops, > + struct module *owner) > +{ > + struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev); > + > + cdev_init(&pdata->cdev, fops); > + pdata->cdev.owner = owner; > + > + /* > + * set parent to the feature device so that its refcount is > + * decreased after the last refcount of cdev is gone, that > + * makes sure the feature device is valid during device > + * file's life-cycle. > + */ > + pdata->cdev.kobj.parent = &pdev->dev.kobj; > + > + return cdev_add(&pdata->cdev, pdev->dev.devt, 1); > +} > +EXPORT_SYMBOL_GPL(dfl_fpga_register_dev_ops); > + > +/** > + * dfl_fpga_unregister_dev_ops - unregister cdev ops for feature dev > + * @pdev: feature dev. > + */ > +void dfl_fpga_unregister_dev_ops(struct platform_device *pdev) > +{ > + struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev); > + > + cdev_del(&pdata->cdev); > +} > +EXPORT_SYMBOL_GPL(dfl_fpga_unregister_dev_ops); > + > /** > * struct build_feature_devs_info - info collected during feature dev build. > * > @@ -208,9 +298,13 @@ static int build_info_commit_dev(struct build_feature_devs_info *binfo) > enum dfl_id_type type, const char *name, > void __iomem *ioaddr) > { > + enum dfl_fpga_devt_type devt_type = DFL_FPGA_DEVT_FME; > struct platform_device *fdev; > int ret; > > + if (type == PORT_ID) > + devt_type = DFL_FPGA_DEVT_PORT; > + > /* we will create a new device, commit current device first */ > ret = build_info_commit_dev(binfo); > if (ret) > @@ -234,6 +328,7 @@ static int build_info_commit_dev(struct build_feature_devs_info *binfo) > return fdev->id; > > fdev->dev.parent = &binfo->cdev->region->dev; > + fdev->dev.devt = dfl_get_devt(devt_type, fdev->id); > > return 0; > } > @@ -702,13 +797,20 @@ void dfl_fpga_remove_feature_devs(struct dfl_fpga_cdev *cdev) > > static int __init dfl_fpga_init(void) > { > + int ret; > + > dfl_ids_init(); > > - return 0; > + ret = dfl_chardev_init(); > + if (ret) > + dfl_ids_destroy(); > + > + return ret; > } > > static void __exit dfl_fpga_exit(void) > { > + dfl_chardev_uinit(); > dfl_ids_destroy(); > } > > diff --git a/drivers/fpga/dfl.h b/drivers/fpga/dfl.h > index 2ede915..5fcb1a1 100644 > --- a/drivers/fpga/dfl.h > +++ b/drivers/fpga/dfl.h > @@ -15,6 +15,7 @@ > #define __FPGA_DFL_H > > #include <linux/bitfield.h> > +#include <linux/cdev.h> > #include <linux/delay.h> > #include <linux/fs.h> > #include <linux/iopoll.h> > @@ -150,6 +151,7 @@ struct dfl_feature { > * > * @node: node to link feature devs to container device's port_dev_list. > * @lock: mutex to protect platform data. > + * @cdev: cdev of feature dev. > * @dev: ptr to platform device linked with this platform data. > * @dfl_cdev: ptr to container device. > * @disable_count: count for port disable. > @@ -159,6 +161,7 @@ struct dfl_feature { > struct dfl_feature_platform_data { > struct list_head node; > struct mutex lock; > + struct cdev cdev; > struct platform_device *dev; > struct dfl_fpga_cdev *dfl_cdev; > unsigned int disable_count; > @@ -176,6 +179,17 @@ static inline int dfl_feature_platform_data_size(const int num) > num * sizeof(struct dfl_feature); > } > > +enum dfl_fpga_devt_type { > + DFL_FPGA_DEVT_FME, > + DFL_FPGA_DEVT_PORT, > + DFL_FPGA_DEVT_MAX, > +}; Could you move this enum to be close to other similar enums (like dfl_id_type)? The dfl code has a few enums that are similar, and may need updating (or not) as feature are added. Putting them close together with appropriate comments would be helpful to keep them all straight. > + > +int dfl_fpga_register_dev_ops(struct platform_device *pdev, > + const struct file_operations *fops, > + struct module *owner); > +void dfl_fpga_unregister_dev_ops(struct platform_device *pdev); > + > #define dfl_fpga_dev_for_each_feature(pdata, feature) \ > for ((feature) = (pdata)->features; \ > (feature) < (pdata)->features + (pdata)->num; (feature)++) > -- > 1.8.3.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html