From 0979ffda12b636fab58228c2b40bab1e2f6b327b Mon Sep 17 00:00:00 2001
From: Nikita Shubin <n.shubin@yadro.com>
Date: Tue, 2 Nov 2021 17:39:11 +0300
Subject: [PATCH] lib: utils/gpio: use list for drivers

Convert static array to sbi_list.

This removes size limitation, makes add/remove more efficient and
saves space.

Signed-off-by: Nikita Shubin <n.shubin@yadro.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
---
 include/sbi_utils/gpio/gpio.h |  8 ++++++++
 lib/utils/gpio/gpio.c         | 42 ++++++++++++------------------------------
 2 files changed, 20 insertions(+), 30 deletions(-)

diff --git a/include/sbi_utils/gpio/gpio.h b/include/sbi_utils/gpio/gpio.h
index 167d11a..7a3d8bb 100644
--- a/include/sbi_utils/gpio/gpio.h
+++ b/include/sbi_utils/gpio/gpio.h
@@ -11,6 +11,7 @@
 #define __GPIO_H__
 
 #include <sbi/sbi_types.h>
+#include <sbi/sbi_list.h>
 
 #define GPIO_LINE_DIRECTION_IN	1
 #define GPIO_LINE_DIRECTION_OUT	0
@@ -70,8 +71,15 @@ struct gpio_chip {
 	int (*get)(struct gpio_pin *gp);
 	/** Set output value for GPIO pin */
 	void (*set)(struct gpio_pin *gp, int value);
+	/** List */
+	struct sbi_dlist node;
 };
 
+static inline struct gpio_chip *to_gpio_chip(struct sbi_dlist *node)
+{
+	return container_of(node, struct gpio_chip, node);
+}
+
 /** Find a registered GPIO chip */
 struct gpio_chip *gpio_chip_find(unsigned int id);
 
diff --git a/lib/utils/gpio/gpio.c b/lib/utils/gpio/gpio.c
index fb30c0f..3a3a6b2 100644
--- a/lib/utils/gpio/gpio.c
+++ b/lib/utils/gpio/gpio.c
@@ -10,58 +10,40 @@
 #include <sbi/sbi_error.h>
 #include <sbi_utils/gpio/gpio.h>
 
-#define GPIO_CHIP_MAX		16
-
-static struct gpio_chip *gc_array[GPIO_CHIP_MAX];
+static SBI_LIST_HEAD(gpio_chip_list);
 
 struct gpio_chip *gpio_chip_find(unsigned int id)
 {
-	unsigned int i;
-	struct gpio_chip *ret = NULL;
-
-	for (i = 0; i < GPIO_CHIP_MAX; i++) {
-		if (gc_array[i] && gc_array[i]->id == id) {
-			ret = gc_array[i];
-			break;
-		}
+	struct sbi_dlist *pos;
+
+	sbi_list_for_each(pos, &(gpio_chip_list)) {
+		struct gpio_chip *chip = to_gpio_chip(pos);
+
+		if (chip->id == id)
+			return chip;
 	}
 
-	return ret;
+	return NULL;
 }
 
 int gpio_chip_add(struct gpio_chip *gc)
 {
-	int i, ret = SBI_ENOSPC;
-
 	if (!gc)
 		return SBI_EINVAL;
 	if (gpio_chip_find(gc->id))
 		return SBI_EALREADY;
 
-	for (i = 0; i < GPIO_CHIP_MAX; i++) {
-		if (!gc_array[i]) {
-			gc_array[i] = gc;
-			ret = 0;
-			break;
-		}
-	}
+	sbi_list_add(&(gc->node), &(gpio_chip_list));
 
-	return ret;
+	return 0;
 }
 
 void gpio_chip_remove(struct gpio_chip *gc)
 {
-	int i;
-
 	if (!gc)
 		return;
 
-	for (i = 0; i < GPIO_CHIP_MAX; i++) {
-		if (gc_array[i] == gc) {
-			gc_array[i] = NULL;
-			break;
-		}
-	}
+	sbi_list_del(&(gc->node));
 }
 
 int gpio_get_direction(struct gpio_pin *gp)
-- 
2.7.4