[PATCHv2 2/3] clk: samsung: cpu: use kzalloc_flex

[Rosen Penev <rosenp@gmail.com>]

Use a flexible array member to combine allocations.

As kmemdup_array is really kcalloc + memcpy and kzalloc_flex kzalloc +
kcalloc, kzalloc and kcalloc combine leaving the memcpy.

Add __counted_by for extra runtime analysis. Remove fake const num_cfgs.
It needs to be assigned for __counted_by to work.

Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 drivers/clk/samsung/clk-cpu.c | 34 ++++++++++++++--------------------
 1 file changed, 14 insertions(+), 20 deletions(-)

diff --git a/drivers/clk/samsung/clk-cpu.c b/drivers/clk/samsung/clk-cpu.c
index ffc33e5decf5..37cf47533dc6 100644
--- a/drivers/clk/samsung/clk-cpu.c
+++ b/drivers/clk/samsung/clk-cpu.c
@@ -101,11 +101,11 @@ struct exynos_cpuclk {
 	const struct clk_hw			*alt_parent;
 	void __iomem				*base;
 	spinlock_t				*lock;
-	const struct exynos_cpuclk_cfg_data	*cfg;
-	const unsigned long			num_cfgs;
+	unsigned long				num_cfgs;
 	struct notifier_block			clk_nb;
 	unsigned long				flags;
 	const struct exynos_cpuclk_chip		*chip;
+	struct exynos_cpuclk_cfg_data		cfg[] __counted_by(num_cfgs);
 };
 
 /* ---- Common code --------------------------------------------------------- */
@@ -660,10 +660,6 @@ static int __init exynos_register_cpu_clock(struct samsung_clk_provider *ctx,
 		return -EINVAL;
 	}
 
-	cpuclk = kzalloc_obj(*cpuclk);
-	if (!cpuclk)
-		return -ENOMEM;
-
 	parent_name = clk_hw_get_name(parent);
 
 	init.name = clk_data->name;
@@ -672,6 +668,17 @@ static int __init exynos_register_cpu_clock(struct samsung_clk_provider *ctx,
 	init.num_parents = 1;
 	init.ops = &exynos_cpuclk_clk_ops;
 
+	/* Find count of configuration rates in cfg */
+	for (num_cfgs = 0; clk_data->cfg[num_cfgs].prate != 0; )
+		num_cfgs++;
+
+	cpuclk = kzalloc_flex(*cpuclk, cfg, num_cfgs);
+	if (!cpuclk)
+		return -ENOMEM;
+
+	cpuclk->num_cfgs = num_cfgs;
+
+	memcpy(cpuclk->cfg, clk_data->cfg, num_cfgs * sizeof(*cpuclk->cfg));
 	cpuclk->alt_parent = alt_parent;
 	cpuclk->hw.init = &init;
 	cpuclk->base = ctx->reg_base + clk_data->offset;
@@ -687,29 +694,16 @@ static int __init exynos_register_cpu_clock(struct samsung_clk_provider *ctx,
 		goto free_cpuclk;
 	}
 
-	/* Find count of configuration rates in cfg */
-	for (num_cfgs = 0; clk_data->cfg[num_cfgs].prate != 0; )
-		num_cfgs++;
-
-	cpuclk->cfg = kmemdup_array(clk_data->cfg, num_cfgs, sizeof(*cpuclk->cfg),
-				    GFP_KERNEL);
-	if (!cpuclk->cfg) {
-		ret = -ENOMEM;
-		goto unregister_clk_nb;
-	}
-
 	ret = clk_hw_register(NULL, &cpuclk->hw);
 	if (ret) {
 		pr_err("%s: could not register cpuclk %s\n", __func__,
 		       clk_data->name);
-		goto free_cpuclk_data;
+		goto unregister_clk_nb;
 	}
 
 	samsung_clk_add_lookup(ctx, &cpuclk->hw, clk_data->id);
 	return 0;
 
-free_cpuclk_data:
-	kfree(cpuclk->cfg);
 unregister_clk_nb:
 	clk_notifier_unregister(parent->clk, &cpuclk->clk_nb);
 free_cpuclk:
-- 
2.54.0