1 files changed, 190 insertions, 0 deletions
diff --git a/drivers/soc/aspeed/aspeed-bmc-misc.c b/drivers/soc/aspeed/aspeed-bmc-misc.c
new file mode 100644
index 000000000000..314007bad74f
--- /dev/null
+++ b/drivers/soc/aspeed/aspeed-bmc-misc.c
@@ -0,0 +1,190 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright 2018 IBM Corp.
+
+#include <linux/kobject.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+
+#define DEVICE_NAME "aspeed-bmc-misc"
+
+struct aspeed_bmc_ctrl {
+	const char *name;
+	u32 offset;
+	u32 mask;
+	u32 shift;
+	struct regmap *map;
+	struct kobj_attribute attr;
+};
+
+struct aspeed_bmc_misc {
+	struct device *dev;
+	struct regmap *map;
+	struct aspeed_bmc_ctrl *ctrls;
+	int nr_ctrls;
+};
+
+static int aspeed_bmc_misc_parse_dt_child(struct device_node *child,
+					  struct aspeed_bmc_ctrl *ctrl)
+{
+	int rc;
+
+	/* Example child:
+	 *
+	 * ilpc2ahb {
+	 *     offset = <0x80>;
+	 *     bit-mask = <0x1>;
+	 *     bit-shift = <6>;
+	 *     label = "foo";
+	 * }
+	 */
+	if (of_property_read_string(child, "label", &ctrl->name))
+		ctrl->name = child->name;
+
+	rc = of_property_read_u32(child, "offset", &ctrl->offset);
+	if (rc < 0)
+		return rc;
+
+	rc = of_property_read_u32(child, "bit-mask", &ctrl->mask);
+	if (rc < 0)
+		return rc;
+
+	rc = of_property_read_u32(child, "bit-shift", &ctrl->shift);
+	if (rc < 0)
+		return rc;
+
+	ctrl->mask <<= ctrl->shift;
+
+	return 0;
+}
+
+static int aspeed_bmc_misc_parse_dt(struct aspeed_bmc_misc *bmc,
+				    struct device_node *parent)
+{
+	struct aspeed_bmc_ctrl *ctrl;
+	struct device_node *child;
+	int rc;
+
+	bmc->nr_ctrls = of_get_child_count(parent);
+	bmc->ctrls = devm_kcalloc(bmc->dev, bmc->nr_ctrls, sizeof(*bmc->ctrls),
+				  GFP_KERNEL);
+	if (!bmc->ctrls)
+		return -ENOMEM;
+
+	ctrl = bmc->ctrls;
+	for_each_child_of_node(parent, child) {
+		rc = aspeed_bmc_misc_parse_dt_child(child, ctrl++);
+		if (rc < 0) {
+			of_node_put(child);
+			return rc;
+		}
+	}
+
+	return 0;
+}
+
+static ssize_t aspeed_bmc_misc_show(struct kobject *kobj,
+				    struct kobj_attribute *attr, char *buf)
+{
+	struct aspeed_bmc_ctrl *ctrl;
+	unsigned int val;
+	int rc;
+
+	ctrl = container_of(attr, struct aspeed_bmc_ctrl, attr);
+	rc = regmap_read(ctrl->map, ctrl->offset, &val);
+	if (rc)
+		return rc;
+
+	val &= ctrl->mask;
+	val >>= ctrl->shift;
+
+	return sprintf(buf, "%u\n", val);
+}
+
+static ssize_t aspeed_bmc_misc_store(struct kobject *kobj,
+				     struct kobj_attribute *attr,
+				     const char *buf, size_t count)
+{
+	struct aspeed_bmc_ctrl *ctrl;
+	long val;
+	int rc;
+
+	rc = kstrtol(buf, 0, &val);
+	if (rc)
+		return rc;
+
+	ctrl = container_of(attr, struct aspeed_bmc_ctrl, attr);
+	val <<= ctrl->shift;
+	rc = regmap_update_bits(ctrl->map, ctrl->offset, ctrl->mask, val);
+
+	return rc < 0 ? rc : count;
+}
+
+static int aspeed_bmc_misc_add_sysfs_attr(struct aspeed_bmc_misc *bmc,
+					  struct aspeed_bmc_ctrl *ctrl)
+{
+	ctrl->map = bmc->map;
+
+	sysfs_attr_init(&ctrl->attr.attr);
+	ctrl->attr.attr.name = ctrl->name;
+	ctrl->attr.attr.mode = 0664;
+	ctrl->attr.show = aspeed_bmc_misc_show;
+	ctrl->attr.store = aspeed_bmc_misc_store;
+
+	return sysfs_create_file(&bmc->dev->kobj, &ctrl->attr.attr);
+}
+
+static int aspeed_bmc_misc_populate_sysfs(struct aspeed_bmc_misc *bmc)
+{
+	int rc;
+	int i;
+
+	for (i = 0; i < bmc->nr_ctrls; i++) {
+		rc = aspeed_bmc_misc_add_sysfs_attr(bmc, &bmc->ctrls[i]);
+		if (rc < 0)
+			return rc;
+	}
+
+	return 0;
+}
+
+static int aspeed_bmc_misc_probe(struct platform_device *pdev)
+{
+	struct aspeed_bmc_misc *bmc;
+	int rc;
+
+	bmc = devm_kzalloc(&pdev->dev, sizeof(*bmc), GFP_KERNEL);
+	if (!bmc)
+		return -ENOMEM;
+
+	bmc->dev = &pdev->dev;
+	bmc->map = syscon_node_to_regmap(pdev->dev.parent->of_node);
+	if (IS_ERR(bmc->map))
+		return PTR_ERR(bmc->map);
+
+	rc = aspeed_bmc_misc_parse_dt(bmc, pdev->dev.of_node);
+	if (rc < 0)
+		return rc;
+
+	return aspeed_bmc_misc_populate_sysfs(bmc);
+}
+
+static const struct of_device_id aspeed_bmc_misc_match[] = {
+	{ .compatible = "aspeed,bmc-misc" },
+	{ },
+};
+
+static struct platform_driver aspeed_bmc_misc = {
+	.driver = {
+		.name		= DEVICE_NAME,
+		.of_match_table = aspeed_bmc_misc_match,
+	},
+	.probe = aspeed_bmc_misc_probe,
+};
+
+module_platform_driver(aspeed_bmc_misc);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Andrew Jeffery <andrew@aj.id.au>");