interconnect: Add bulk API helpers

There are drivers which just need to get multiple interconnect paths,
request some predefined amounts of bandwidth and then just toggle the
paths between enabled/disabled state.

The aim of this patch is simplify the above and to allow drivers to put
all the path names and bandwidth data into a single static icc_bulk_data
table and call the icc_bulk_* functions on that table in order to scale
all the interconnect paths in parallel.

Suggested-by: Evan Green <evgreen@chromium.org>
Suggested-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20200729123439.9961-1-georgi.djakov@linaro.org
Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>

1 files changed, 117 insertions, 0 deletions

diff --git a/drivers/interconnect/bulk.c b/drivers/interconnect/bulk.c
new file mode 100644
index 000000000000..73e2c8d0a412
--- /dev/null
+++ b/drivers/interconnect/bulk.c
@@ -0,0 +1,117 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/interconnect-provider.h>
+#include <linux/device.h>
+#include <linux/export.h>
+
+/**
+ * of_icc_bulk_get() - get interconnect paths
+ * @dev: the device requesting the path
+ * @num_paths: the number of icc_bulk_data
+ * @paths: the table with the paths we want to get
+ *
+ * Returns 0 on success or negative errno otherwise.
+ */
+int __must_check of_icc_bulk_get(struct device *dev, int num_paths,
+				 struct icc_bulk_data *paths)
+{
+	int ret, i;
+
+	for (i = 0; i < num_paths; i++) {
+		paths[i].path = of_icc_get(dev, paths[i].name);
+		if (IS_ERR(paths[i].path)) {
+			ret = PTR_ERR(paths[i].path);
+			if (ret != -EPROBE_DEFER)
+				dev_err(dev, "of_icc_get() failed on path %s (%d)\n",
+					paths[i].name, ret);
+			paths[i].path = NULL;
+			goto err;
+		}
+	}
+
+	return 0;
+
+err:
+	icc_bulk_put(i, paths);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(of_icc_bulk_get);
+
+/**
+ * icc_bulk_put() - put a list of interconnect paths
+ * @num_paths: the number of icc_bulk_data
+ * @paths: the icc_bulk_data table with the paths being put
+ */
+void icc_bulk_put(int num_paths, struct icc_bulk_data *paths)
+{
+	while (--num_paths >= 0) {
+		icc_put(paths[num_paths].path);
+		paths[num_paths].path = NULL;
+	}
+}
+EXPORT_SYMBOL_GPL(icc_bulk_put);
+
+/**
+ * icc_bulk_set() - set bandwidth to a set of paths
+ * @num_paths: the number of icc_bulk_data
+ * @paths: the icc_bulk_data table containing the paths and bandwidth
+ *
+ * Returns 0 on success or negative errno otherwise.
+ */
+int icc_bulk_set_bw(int num_paths, const struct icc_bulk_data *paths)
+{
+	int ret = 0;
+	int i;
+
+	for (i = 0; i < num_paths; i++) {
+		ret = icc_set_bw(paths[i].path, paths[i].avg_bw, paths[i].peak_bw);
+		if (ret) {
+			pr_err("icc_set_bw() failed on path %s (%d)\n", paths[i].name, ret);
+			return ret;
+		}
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(icc_bulk_set_bw);
+
+/**
+ * icc_bulk_enable() - enable a previously disabled set of paths
+ * @num_paths: the number of icc_bulk_data
+ * @paths: the icc_bulk_data table containing the paths and bandwidth
+ *
+ * Returns 0 on success or negative errno otherwise.
+ */
+int icc_bulk_enable(int num_paths, const struct icc_bulk_data *paths)
+{
+	int ret, i;
+
+	for (i = 0; i < num_paths; i++) {
+		ret = icc_enable(paths[i].path);
+		if (ret) {
+			pr_err("icc_enable() failed on path %s (%d)\n", paths[i].name, ret);
+			goto err;
+		}
+	}
+
+	return 0;
+
+err:
+	icc_bulk_disable(i, paths);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(icc_bulk_enable);
+
+/**
+ * icc_bulk_disable() - disable a set of interconnect paths
+ * @num_paths: the number of icc_bulk_data
+ * @paths: the icc_bulk_data table containing the paths and bandwidth
+ */
+void icc_bulk_disable(int num_paths, const struct icc_bulk_data *paths)
+{
+	while (--num_paths >= 0)
+		icc_disable(paths[num_paths].path);
+}
+EXPORT_SYMBOL_GPL(icc_bulk_disable);