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authorDragan Cvetic <dragan.cvetic@xilinx.com>2019-06-11 20:29:36 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-06-21 17:12:05 +0300
commit76d83e1c32334a793e50de6f955c2eefcc60bb8e (patch)
treec6828ef5e36ef90709e3e8d2c4248548894b1afc /drivers/misc/xilinx_sdfec.c
parenta00b004218be6b907a1e14ae0bc33f363e70e176 (diff)
downloadlinux-76d83e1c32334a793e50de6f955c2eefcc60bb8e.tar.xz
misc: xilinx-sdfec: add core driver
Implement a platform driver that matches with xlnx, sd-fec-1.1 device tree node and registers as a character device, including: - SD-FEC driver binds to sdfec DT node. - creates and initialise an initial driver dev structure. - add the driver in Linux build and Kconfig. Tested-by: Dragan Cvetic <dragan.cvetic@xilinx.com> Signed-off-by: Derek Kiernan <derek.kiernan@xilinx.com> Signed-off-by: Dragan Cvetic <dragan.cvetic@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/misc/xilinx_sdfec.c')
-rw-r--r--drivers/misc/xilinx_sdfec.c162
1 files changed, 162 insertions, 0 deletions
diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c
new file mode 100644
index 000000000000..ff0704be8686
--- /dev/null
+++ b/drivers/misc/xilinx_sdfec.c
@@ -0,0 +1,162 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Xilinx SDFEC
+ *
+ * Copyright (C) 2019 Xilinx, Inc.
+ *
+ * Description:
+ * This driver is developed for SDFEC16 (Soft Decision FEC 16nm)
+ * IP. It exposes a char device which supports file operations
+ * like open(), close() and ioctl().
+ */
+
+#include <linux/miscdevice.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/poll.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+
+#define DEV_NAME_LEN 12
+
+static struct idr dev_idr;
+static struct mutex dev_idr_lock;
+
+/**
+ * struct xsdfec_dev - Driver data for SDFEC
+ * @regs: device physical base address
+ * @dev: pointer to device struct
+ * @miscdev: Misc device handle
+ * @error_data_lock: Error counter and states spinlock
+ * @dev_name: Device name
+ * @dev_id: Device ID
+ *
+ * This structure contains necessary state for SDFEC driver to operate
+ */
+struct xsdfec_dev {
+ void __iomem *regs;
+ struct device *dev;
+ struct miscdevice miscdev;
+ /* Spinlock to protect state_updated and stats_updated */
+ spinlock_t error_data_lock;
+ char dev_name[DEV_NAME_LEN];
+ int dev_id;
+};
+
+static const struct file_operations xsdfec_fops = {
+ .owner = THIS_MODULE,
+};
+
+static void xsdfec_idr_remove(struct xsdfec_dev *xsdfec)
+{
+ mutex_lock(&dev_idr_lock);
+ idr_remove(&dev_idr, xsdfec->dev_id);
+ mutex_unlock(&dev_idr_lock);
+}
+
+static int xsdfec_probe(struct platform_device *pdev)
+{
+ struct xsdfec_dev *xsdfec;
+ struct device *dev;
+ struct resource *res;
+ int err;
+
+ xsdfec = devm_kzalloc(&pdev->dev, sizeof(*xsdfec), GFP_KERNEL);
+ if (!xsdfec)
+ return -ENOMEM;
+
+ xsdfec->dev = &pdev->dev;
+ spin_lock_init(&xsdfec->error_data_lock);
+
+ dev = xsdfec->dev;
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ xsdfec->regs = devm_ioremap_resource(dev, res);
+ if (IS_ERR(xsdfec->regs)) {
+ err = PTR_ERR(xsdfec->regs);
+ return err;
+ }
+
+ /* Save driver private data */
+ platform_set_drvdata(pdev, xsdfec);
+
+ mutex_lock(&dev_idr_lock);
+ err = idr_alloc(&dev_idr, xsdfec->dev_name, 0, 0, GFP_KERNEL);
+ mutex_unlock(&dev_idr_lock);
+ if (err < 0)
+ goto err_xsddev_idr;
+ xsdfec->dev_id = err;
+
+ snprintf(xsdfec->dev_name, DEV_NAME_LEN, "xsdfec%d", xsdfec->dev_id);
+ xsdfec->miscdev.minor = MISC_DYNAMIC_MINOR;
+ xsdfec->miscdev.name = xsdfec->dev_name;
+ xsdfec->miscdev.fops = &xsdfec_fops;
+ xsdfec->miscdev.parent = dev;
+ err = misc_register(&xsdfec->miscdev);
+ if (err) {
+ dev_err(dev, "error:%d. Unable to register device", err);
+ return err;
+ }
+ return 0;
+
+err_xsddev_idr:
+ xsdfec_idr_remove(xsdfec);
+
+ return err;
+}
+
+static int xsdfec_remove(struct platform_device *pdev)
+{
+ struct xsdfec_dev *xsdfec;
+
+ xsdfec = platform_get_drvdata(pdev);
+ misc_deregister(&xsdfec->miscdev);
+ xsdfec_idr_remove(xsdfec);
+ return 0;
+}
+
+static const struct of_device_id xsdfec_of_match[] = {
+ {
+ .compatible = "xlnx,sd-fec-1.1",
+ },
+ { /* end of table */ }
+};
+MODULE_DEVICE_TABLE(of, xsdfec_of_match);
+
+static struct platform_driver xsdfec_driver = {
+ .driver = {
+ .name = "xilinx-sdfec",
+ .of_match_table = xsdfec_of_match,
+ },
+ .probe = xsdfec_probe,
+ .remove = xsdfec_remove,
+};
+
+static int __init xsdfec_init(void)
+{
+ int err;
+
+ mutex_init(&dev_idr_lock);
+ idr_init(&dev_idr);
+ err = platform_driver_register(&xsdfec_driver);
+ if (err < 0) {
+ pr_err("%s Unabled to register SDFEC driver", __func__);
+ return err;
+ }
+ return 0;
+}
+
+static void __exit xsdfec_exit(void)
+{
+ platform_driver_unregister(&xsdfec_driver);
+ idr_destroy(&dev_idr);
+}
+
+module_init(xsdfec_init);
+module_exit(xsdfec_exit);
+
+MODULE_AUTHOR("Xilinx, Inc");
+MODULE_DESCRIPTION("Xilinx SD-FEC16 Driver");
+MODULE_LICENSE("GPL");