From: Vadim Pasternak <vadimp@mellanox.com>
Date: Tue, 14 Jul 2020 15:01:56 +0300
Subject: platform/mellanox: mlxreg-hotplug: Use capability register for
 attribute creation
Patch-mainline: v5.9-rc1
Git-commit: 0a43f7be57edbe9fac6084a6f92694a3badee827
References: bsc#1176774

Create the 'sysfs' attributes according to configuration provided
through the capability register, which purpose is to indicate the
actual number of the components within the particular group.
Such components could be, for example the FAN or power supply units.
The motivation is to avoid adding a new code in the future in order to
distinct between the systems types supporting a different number of the
components like power supplies, FANs, ASICs, line cards.

Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/platform/mellanox/mlxreg-hotplug.c |   60 +++++++++++++++++++----------
 1 file changed, 41 insertions(+), 19 deletions(-)

--- a/drivers/platform/mellanox/mlxreg-hotplug.c
+++ b/drivers/platform/mellanox/mlxreg-hotplug.c
@@ -170,17 +170,49 @@ static int mlxreg_hotplug_attr_init(stru
 	struct mlxreg_core_hotplug_platform_data *pdata;
 	struct mlxreg_core_item *item;
 	struct mlxreg_core_data *data;
-	int num_attrs = 0, id = 0, i, j;
+	unsigned long mask;
+	u32 regval;
+	int num_attrs = 0, id = 0, i, j, k, ret;
 
 	pdata = dev_get_platdata(&priv->pdev->dev);
 	item = pdata->items;
 
 	/* Go over all kinds of items - psu, pwr, fan. */
 	for (i = 0; i < pdata->counter; i++, item++) {
-		num_attrs += item->count;
+		if (item->capability) {
+			/*
+			 * Read group capability register to get actual number
+			 * of interrupt capable components and set group mask
+			 * accordingly.
+			 */
+			ret = regmap_read(priv->regmap, item->capability,
+					  &regval);
+			if (ret)
+				return ret;
+
+			item->mask = GENMASK((regval & item->mask) - 1, 0);
+		}
+
 		data = item->data;
-		/* Go over all units within the item. */
-		for (j = 0; j < item->count; j++, data++, id++) {
+
+		/* Go over all unmasked units within item. */
+		mask = item->mask;
+		k = 0;
+		for_each_set_bit(j, &mask, item->count) {
+			if (data->capability) {
+				/*
+				 * Read capability register and skip non
+				 * relevant attributes.
+				 */
+				ret = regmap_read(priv->regmap,
+						  data->capability, &regval);
+				if (ret)
+					return ret;
+				if (!(regval & data->bit)) {
+					data++;
+					continue;
+				}
+			}
 			PRIV_ATTR(id) = &PRIV_DEV_ATTR(id).dev_attr.attr;
 			PRIV_ATTR(id)->name = devm_kasprintf(&priv->pdev->dev,
 							     GFP_KERNEL,
@@ -198,9 +230,13 @@ static int mlxreg_hotplug_attr_init(stru
 			PRIV_DEV_ATTR(id).dev_attr.show =
 						mlxreg_hotplug_attr_show;
 			PRIV_DEV_ATTR(id).nr = i;
-			PRIV_DEV_ATTR(id).index = j;
+			PRIV_DEV_ATTR(id).index = k;
 			sysfs_attr_init(&PRIV_DEV_ATTR(id).dev_attr.attr);
+			data++;
+			id++;
+			k++;
 		}
+		num_attrs += k;
 	}
 
 	priv->group.attrs = devm_kcalloc(&priv->pdev->dev,
@@ -478,20 +514,6 @@ static int mlxreg_hotplug_set_irq(struct
 	item = pdata->items;
 
 	for (i = 0; i < pdata->counter; i++, item++) {
-		if (item->capability) {
-			/*
-			 * Read group capability register to get actual number
-			 * of interrupt capable components and set group mask
-			 * accordingly.
-			 */
-			ret = regmap_read(priv->regmap, item->capability,
-					  &regval);
-			if (ret)
-				goto out;
-
-			item->mask = GENMASK((regval & item->mask) - 1, 0);
-		}
-
 		/* Clear group presense event. */
 		ret = regmap_write(priv->regmap, item->reg +
 				   MLXREG_HOTPLUG_EVENT_OFF, 0);