[PATCH V4 04/12] misc: xilinx_sdfec: Add open, close and ioctl

From: Dragan Cvetic
Date: Sat May 25 2019 - 07:41:32 EST


Add char device interface per DT node present and support
file operations:
- open(),
- close(),
- unlocked_ioctl(),
- compat_ioctl().

Tested-by: Dragan Cvetic <dragan.cvetic@xxxxxxxxxx>
Signed-off-by: Derek Kiernan <derek.kiernan@xxxxxxxxxx>
Signed-off-by: Dragan Cvetic <dragan.cvetic@xxxxxxxxxx>
---
drivers/misc/xilinx_sdfec.c | 57 +++++++++++++++++++++++++++++++++++++---
include/uapi/misc/xilinx_sdfec.h | 4 +++
2 files changed, 58 insertions(+), 3 deletions(-)

diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c
index ff32d29..740b487 100644
--- a/drivers/misc/xilinx_sdfec.c
+++ b/drivers/misc/xilinx_sdfec.c
@@ -51,7 +51,6 @@ struct xsdfec_clks {
* @regs: device physical base address
* @dev: pointer to device struct
* @config: Configuration of the SDFEC device
- * @open_count: Count of char device being opened
* @miscdev: Misc device handle
* @irq_lock: Driver spinlock
* @clks: Clocks managed by the SDFEC driver
@@ -62,15 +61,68 @@ struct xsdfec_dev {
void __iomem *regs;
struct device *dev;
struct xsdfec_config config;
- atomic_t open_count;
struct miscdevice miscdev;
/* Spinlock to protect state_updated and stats_updated */
spinlock_t irq_lock;
struct xsdfec_clks clks;
};

+static int xsdfec_dev_open(struct inode *iptr, struct file *fptr)
+{
+ return 0;
+}
+
+static int xsdfec_dev_release(struct inode *iptr, struct file *fptr)
+{
+ return 0;
+}
+
+static long xsdfec_dev_ioctl(struct file *fptr, unsigned int cmd,
+ unsigned long data)
+{
+ struct xsdfec_dev *xsdfec;
+ void __user *arg = NULL;
+ int rval = -EINVAL;
+
+ xsdfec = container_of(fptr->private_data, struct xsdfec_dev, miscdev);
+ if (!xsdfec)
+ return rval;
+
+ if (_IOC_TYPE(cmd) != XSDFEC_MAGIC)
+ return -ENOTTY;
+
+ /* check if ioctl argument is present and valid */
+ if (_IOC_DIR(cmd) != _IOC_NONE) {
+ arg = (void __user *)data;
+ if (!arg)
+ return rval;
+ }
+
+ switch (cmd) {
+ default:
+ /* Should not get here */
+ dev_warn(xsdfec->dev, "Undefined SDFEC IOCTL");
+ break;
+ }
+ return rval;
+}
+
+#ifdef CONFIG_COMPAT
+static long xsdfec_dev_compat_ioctl(struct file *file, unsigned int cmd,
+ unsigned long data)
+{
+ return xsdfec_dev_ioctl(file, cmd, (unsigned long)compat_ptr(data));
+}
+#endif
+
static const struct file_operations xsdfec_fops = {
.owner = THIS_MODULE,
+ .open = xsdfec_dev_open,
+ .release = xsdfec_dev_release,
+ .unlocked_ioctl = xsdfec_dev_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = xsdfec_dev_compat_ioctl,
+#endif
};

static int xsdfec_clk_init(struct platform_device *pdev,
@@ -270,7 +322,6 @@ static int xsdfec_probe(struct platform_device *pdev)
goto err_xsdfec_dev;
}

- atomic_set(&xsdfec->open_count, 1);
dev_info(dev, "XSDFEC%d Probe Successful", xsdfec->config.fec_id);
atomic_inc(&xsdfec_ndevs);
return 0;
diff --git a/include/uapi/misc/xilinx_sdfec.h b/include/uapi/misc/xilinx_sdfec.h
index 1b8a63f..791d412 100644
--- a/include/uapi/misc/xilinx_sdfec.h
+++ b/include/uapi/misc/xilinx_sdfec.h
@@ -41,4 +41,8 @@ struct xsdfec_config {
__s32 fec_id;
};

+/*
+ * XSDFEC IOCTL List
+ */
+#define XSDFEC_MAGIC 'f'
#endif /* __XILINX_SDFEC_H__ */
--
2.7.4