[PATCHv2 3/3] clk: samsung: pll: use kzalloc_flex

[Rosen Penev <rosenp@gmail.com>]

Simplify allocation by using a flexible array member to combine
allocations and remove a kfree.

Use __counted_by for extra runtime analysis.

Since rate_table is now a flexible array member, NULL checks don't work.
So use the counting variable to check allocation.

Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 drivers/clk/samsung/clk-pll.c | 56 ++++++++++++++++-------------------
 1 file changed, 26 insertions(+), 30 deletions(-)

diff --git a/drivers/clk/samsung/clk-pll.c b/drivers/clk/samsung/clk-pll.c
index fdb84bcec912..e74552846ba3 100644
--- a/drivers/clk/samsung/clk-pll.c
+++ b/drivers/clk/samsung/clk-pll.c
@@ -28,7 +28,7 @@ struct samsung_clk_pll {
 	unsigned short		lock_offs;
 	enum samsung_pll_type	type;
 	unsigned int		rate_count;
-	const struct samsung_pll_rate_table *rate_table;
+	struct samsung_pll_rate_table rate_table[] __counted_by(rate_count);
 };
 
 #define to_clk_pll(_hw) container_of(_hw, struct samsung_clk_pll, hw)
@@ -1593,35 +1593,32 @@ static void __init _samsung_clk_register_pll(struct samsung_clk_provider *ctx,
 {
 	struct samsung_clk_pll *pll;
 	struct clk_init_data init;
-	int ret, len;
+	unsigned int len = 0;
+	int ret;
 
-	pll = kzalloc_obj(*pll);
+	if (pll_clk->rate_table) {
+		/* find count of rates in rate_table */
+		while (pll_clk->rate_table[len].rate != 0)
+			len++;
+	}
+
+	pll = kzalloc_flex(*pll, rate_table, len);
 	if (!pll) {
 		pr_err("%s: could not allocate pll clk %s\n",
 			__func__, pll_clk->name);
 		return;
 	}
 
+	pll->rate_count = len;
+	if (len)
+		memcpy(pll->rate_table, pll_clk->rate_table,
+		       len * sizeof(*pll->rate_table));
+
 	init.name = pll_clk->name;
 	init.flags = pll_clk->flags;
 	init.parent_names = &pll_clk->parent_name;
 	init.num_parents = 1;
 
-	if (pll_clk->rate_table) {
-		/* find count of rates in rate_table */
-		for (len = 0; pll_clk->rate_table[len].rate != 0; )
-			len++;
-
-		pll->rate_count = len;
-		pll->rate_table = kmemdup_array(pll_clk->rate_table,
-						pll->rate_count,
-						sizeof(*pll->rate_table),
-						GFP_KERNEL);
-		WARN(!pll->rate_table,
-			"%s: could not allocate rate table for %s\n",
-			__func__, pll_clk->name);
-	}
-
 	switch (pll_clk->type) {
 	case pll_2126:
 		init.ops = &samsung_pll2126_clk_ops;
@@ -1640,7 +1637,7 @@ static void __init _samsung_clk_register_pll(struct samsung_clk_provider *ctx,
 	case pll_a9fracm:
 		pll->enable_offs = PLL35XX_ENABLE_SHIFT;
 		pll->lock_offs = PLL35XX_LOCK_STAT_SHIFT;
-		if (!pll->rate_table)
+		if (!pll->rate_count)
 			init.ops = &samsung_pll35xx_clk_min_ops;
 		else
 			init.ops = &samsung_pll35xx_clk_ops;
@@ -1659,7 +1656,7 @@ static void __init _samsung_clk_register_pll(struct samsung_clk_provider *ctx,
 	case pll_0732x:
 		pll->enable_offs = PLL0822X_ENABLE_SHIFT;
 		pll->lock_offs = PLL0822X_LOCK_STAT_SHIFT;
-		if (!pll->rate_table)
+		if (!pll->rate_count)
 			init.ops = &samsung_pll0822x_clk_min_ops;
 		else
 			init.ops = &samsung_pll0822x_clk_ops;
@@ -1669,7 +1666,7 @@ static void __init _samsung_clk_register_pll(struct samsung_clk_provider *ctx,
 		break;
 	case pll_4502:
 	case pll_4508:
-		if (!pll->rate_table)
+		if (!pll->rate_count)
 			init.ops = &samsung_pll45xx_clk_min_ops;
 		else
 			init.ops = &samsung_pll45xx_clk_ops;
@@ -1679,7 +1676,7 @@ static void __init _samsung_clk_register_pll(struct samsung_clk_provider *ctx,
 	case pll_2650:
 		pll->enable_offs = PLL36XX_ENABLE_SHIFT;
 		pll->lock_offs = PLL36XX_LOCK_STAT_SHIFT;
-		if (!pll->rate_table)
+		if (!pll->rate_count)
 			init.ops = &samsung_pll36xx_clk_min_ops;
 		else
 			init.ops = &samsung_pll36xx_clk_ops;
@@ -1687,7 +1684,7 @@ static void __init _samsung_clk_register_pll(struct samsung_clk_provider *ctx,
 	case pll_0831x:
 		pll->enable_offs = PLL0831X_ENABLE_SHIFT;
 		pll->lock_offs = PLL0831X_LOCK_STAT_SHIFT;
-		if (!pll->rate_table)
+		if (!pll->rate_count)
 			init.ops = &samsung_pll0831x_clk_min_ops;
 		else
 			init.ops = &samsung_pll0831x_clk_ops;
@@ -1703,7 +1700,7 @@ static void __init _samsung_clk_register_pll(struct samsung_clk_provider *ctx,
 	case pll_4650:
 	case pll_4650c:
 	case pll_1460x:
-		if (!pll->rate_table)
+		if (!pll->rate_count)
 			init.ops = &samsung_pll46xx_clk_min_ops;
 		else
 			init.ops = &samsung_pll46xx_clk_ops;
@@ -1712,19 +1709,19 @@ static void __init _samsung_clk_register_pll(struct samsung_clk_provider *ctx,
 		init.ops = &samsung_pll2550x_clk_ops;
 		break;
 	case pll_2550xx:
-		if (!pll->rate_table)
+		if (!pll->rate_count)
 			init.ops = &samsung_pll2550xx_clk_min_ops;
 		else
 			init.ops = &samsung_pll2550xx_clk_ops;
 		break;
 	case pll_2650x:
-		if (!pll->rate_table)
+		if (!pll->rate_count)
 			init.ops = &samsung_pll2650x_clk_min_ops;
 		else
 			init.ops = &samsung_pll2650x_clk_ops;
 		break;
 	case pll_2650xx:
-		if (!pll->rate_table)
+		if (!pll->rate_count)
 			init.ops = &samsung_pll2650xx_clk_min_ops;
 		else
 			init.ops = &samsung_pll2650xx_clk_ops;
@@ -1734,7 +1731,7 @@ static void __init _samsung_clk_register_pll(struct samsung_clk_provider *ctx,
 		init.ops = &samsung_pll531x_clk_ops;
 		break;
 	case pll_1031x:
-		if (!pll->rate_table)
+		if (!pll->rate_count)
 			init.ops = &samsung_pll1031x_clk_min_ops;
 		else
 			init.ops = &samsung_pll1031x_clk_ops;
@@ -1742,7 +1739,7 @@ static void __init _samsung_clk_register_pll(struct samsung_clk_provider *ctx,
 	case pll_a9fraco:
 		pll->enable_offs = PLLA9FRACO_ENABLE_SHIFT;
 		pll->lock_offs = PLLA9FRACO_LOCK_STAT_SHIFT;
-		if (!pll->rate_table)
+		if (!pll->rate_count)
 			init.ops = &samsung_a9fraco_clk_min_ops;
 		else
 			init.ops = &samsung_a9fraco_clk_ops;
@@ -1761,7 +1758,6 @@ static void __init _samsung_clk_register_pll(struct samsung_clk_provider *ctx,
 	if (ret) {
 		pr_err("%s: failed to register pll clock %s : %d\n",
 			__func__, pll_clk->name, ret);
-		kfree(pll->rate_table);
 		kfree(pll);
 		return;
 	}
-- 
2.54.0