1 files changed, 125 insertions, 0 deletions
diff --git a/drivers/staging/fclk/xilinx_fclk.c b/drivers/staging/fclk/xilinx_fclk.c
new file mode 100644
index 000000000000..189928b8dd79
--- /dev/null
+++ b/drivers/staging/fclk/xilinx_fclk.c
@@ -0,0 +1,125 @@
+/*
+ * Copyright (C) 2017 Xilinx, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+
+struct fclk_state {
+	struct device	*dev;
+	struct clk	*pl;
+};
+
+/* Match table for of_platform binding */
+static const struct of_device_id fclk_of_match[] = {
+	{ .compatible = "xlnx,fclk",},
+	{ /* end of list */ },
+};
+MODULE_DEVICE_TABLE(of, fclk_of_match);
+
+static ssize_t set_rate_show(struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	struct fclk_state *st = dev_get_drvdata(dev);
+
+	return scnprintf(buf, PAGE_SIZE, "%lu\n", clk_get_rate(st->pl));
+}
+
+static ssize_t set_rate_store(struct device *dev,
+			      struct device_attribute *attr,
+			      const char *buf, size_t count)
+{
+	int ret = 0;
+	unsigned long rate;
+	struct fclk_state *st = dev_get_drvdata(dev);
+
+	ret = kstrtoul(buf, 0, &rate);
+	if (ret)
+		return -EINVAL;
+
+	rate = clk_round_rate(st->pl, rate);
+	ret = clk_set_rate(st->pl, rate);
+
+	return ret ? ret : count;
+}
+
+static DEVICE_ATTR_RW(set_rate);
+
+static const struct attribute *fclk_ctrl_attrs[] = {
+	&dev_attr_set_rate.attr,
+	NULL,
+};
+
+static const struct attribute_group fclk_ctrl_attr_grp = {
+	.attrs = (struct attribute **)fclk_ctrl_attrs,
+};
+
+static int fclk_probe(struct platform_device *pdev)
+{
+	struct fclk_state *st;
+	int ret;
+	struct device *dev = &pdev->dev;
+
+	st = devm_kzalloc(&pdev->dev, sizeof(*st), GFP_KERNEL);
+	if (!st)
+		return -ENOMEM;
+
+	st->dev = dev;
+	platform_set_drvdata(pdev, st);
+
+	st->pl = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(st->pl))
+		return PTR_ERR(st->pl);
+
+	ret = clk_prepare_enable(st->pl);
+	if (ret) {
+		dev_err(&pdev->dev, "Unable to enable clock.\n");
+		return ret;
+	}
+
+	ret = sysfs_create_group(&dev->kobj, &fclk_ctrl_attr_grp);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int fclk_remove(struct platform_device *pdev)
+{
+	struct fclk_state *st = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(st->pl);
+	return 0;
+}
+
+static struct platform_driver fclk_driver = {
+	.driver = {
+		.name = KBUILD_MODNAME,
+		.of_match_table = fclk_of_match,
+	},
+	.probe		= fclk_probe,
+	.remove		= fclk_remove,
+};
+
+module_platform_driver(fclk_driver);
+
+MODULE_AUTHOR("Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>");
+MODULE_DESCRIPTION("fclk enable");
+MODULE_LICENSE("GPL v2");