[PATCH v3 25/31] clk: mediatek: pll: Implement error handling in register API

Chen-Yu Tsai posted 31 patches 2 years, 9 months ago
[PATCH v3 25/31] clk: mediatek: pll: Implement error handling in register API
Posted by Chen-Yu Tsai 2 years, 9 months ago
The pll clk type registration function does not stop or return errors
if any clk failed to be registered, nor does it implement an error
handling path. This may result in a partially working device if any
step failed.

Make the register function return proper error codes, and bail out if
errors occur. Proper cleanup, i.e. unregister any clks that were
successfully registered, and unmap the I/O space, is done in the new
error path.

Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Reviewed-by: Miles Chen <miles.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
---
 drivers/clk/mediatek/clk-pll.c | 23 +++++++++++++++++++----
 drivers/clk/mediatek/clk-pll.h |  6 +++---
 2 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/drivers/clk/mediatek/clk-pll.c b/drivers/clk/mediatek/clk-pll.c
index 8439d37e354d..817a80293bfc 100644
--- a/drivers/clk/mediatek/clk-pll.c
+++ b/drivers/clk/mediatek/clk-pll.c
@@ -377,8 +377,9 @@ static void mtk_clk_unregister_pll(struct clk *clk)
 	kfree(pll);
 }
 
-void mtk_clk_register_plls(struct device_node *node,
-		const struct mtk_pll_data *plls, int num_plls, struct clk_onecell_data *clk_data)
+int mtk_clk_register_plls(struct device_node *node,
+			  const struct mtk_pll_data *plls, int num_plls,
+			  struct clk_onecell_data *clk_data)
 {
 	void __iomem *base;
 	int i;
@@ -387,7 +388,7 @@ void mtk_clk_register_plls(struct device_node *node,
 	base = of_iomap(node, 0);
 	if (!base) {
 		pr_err("%s(): ioremap failed\n", __func__);
-		return;
+		return -EINVAL;
 	}
 
 	for (i = 0; i < num_plls; i++) {
@@ -397,11 +398,25 @@ void mtk_clk_register_plls(struct device_node *node,
 
 		if (IS_ERR(clk)) {
 			pr_err("Failed to register clk %s: %pe\n", pll->name, clk);
-			continue;
+			goto err;
 		}
 
 		clk_data->clks[pll->id] = clk;
 	}
+
+	return 0;
+
+err:
+	while (--i >= 0) {
+		const struct mtk_pll_data *pll = &plls[i];
+
+		mtk_clk_unregister_pll(clk_data->clks[pll->id]);
+		clk_data->clks[pll->id] = ERR_PTR(-ENOENT);
+	}
+
+	iounmap(base);
+
+	return PTR_ERR(clk);
 }
 EXPORT_SYMBOL_GPL(mtk_clk_register_plls);
 
diff --git a/drivers/clk/mediatek/clk-pll.h b/drivers/clk/mediatek/clk-pll.h
index a889b1e472e7..bf06e44caef9 100644
--- a/drivers/clk/mediatek/clk-pll.h
+++ b/drivers/clk/mediatek/clk-pll.h
@@ -48,9 +48,9 @@ struct mtk_pll_data {
 	u8 pll_en_bit; /* Assume 0, indicates BIT(0) by default */
 };
 
-void mtk_clk_register_plls(struct device_node *node,
-			   const struct mtk_pll_data *plls, int num_plls,
-			   struct clk_onecell_data *clk_data);
+int mtk_clk_register_plls(struct device_node *node,
+			  const struct mtk_pll_data *plls, int num_plls,
+			  struct clk_onecell_data *clk_data);
 void mtk_clk_unregister_plls(const struct mtk_pll_data *plls, int num_plls,
 			     struct clk_onecell_data *clk_data);
 
-- 
2.35.0.263.gb82422642f-goog

Re: [PATCH v3 25/31] clk: mediatek: pll: Implement error handling in register API
Posted by Chun-Jie Chen 2 years, 9 months ago
On Tue, 2022-02-08 at 20:40 +0800, Chen-Yu Tsai wrote:
> The pll clk type registration function does not stop or return errors
> if any clk failed to be registered, nor does it implement an error
> handling path. This may result in a partially working device if any
> step failed.
> 
> Make the register function return proper error codes, and bail out if
> errors occur. Proper cleanup, i.e. unregister any clks that were
> successfully registered, and unmap the I/O space, is done in the new
> error path.
> 
> Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
> Reviewed-by: Miles Chen <miles.chen@mediatek.com>
> Reviewed-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno@collabora.com>

Reviewed-by: Chun-Jie Chen <chun-jie.chen@mediatek.com>
> ---
>  drivers/clk/mediatek/clk-pll.c | 23 +++++++++++++++++++----
>  drivers/clk/mediatek/clk-pll.h |  6 +++---
>  2 files changed, 22 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/clk/mediatek/clk-pll.c
> b/drivers/clk/mediatek/clk-pll.c
> index 8439d37e354d..817a80293bfc 100644
> --- a/drivers/clk/mediatek/clk-pll.c
> +++ b/drivers/clk/mediatek/clk-pll.c
> @@ -377,8 +377,9 @@ static void mtk_clk_unregister_pll(struct clk
> *clk)
>  	kfree(pll);
>  }
>  
> -void mtk_clk_register_plls(struct device_node *node,
> -		const struct mtk_pll_data *plls, int num_plls, struct
> clk_onecell_data *clk_data)
> +int mtk_clk_register_plls(struct device_node *node,
> +			  const struct mtk_pll_data *plls, int
> num_plls,
> +			  struct clk_onecell_data *clk_data)
>  {
>  	void __iomem *base;
>  	int i;
> @@ -387,7 +388,7 @@ void mtk_clk_register_plls(struct device_node
> *node,
>  	base = of_iomap(node, 0);
>  	if (!base) {
>  		pr_err("%s(): ioremap failed\n", __func__);
> -		return;
> +		return -EINVAL;
>  	}
>  
>  	for (i = 0; i < num_plls; i++) {
> @@ -397,11 +398,25 @@ void mtk_clk_register_plls(struct device_node
> *node,
>  
>  		if (IS_ERR(clk)) {
>  			pr_err("Failed to register clk %s: %pe\n", pll-
> >name, clk);
> -			continue;
> +			goto err;
>  		}
>  
>  		clk_data->clks[pll->id] = clk;
>  	}
> +
> +	return 0;
> +
> +err:
> +	while (--i >= 0) {
> +		const struct mtk_pll_data *pll = &plls[i];
> +
> +		mtk_clk_unregister_pll(clk_data->clks[pll->id]);
> +		clk_data->clks[pll->id] = ERR_PTR(-ENOENT);
> +	}
> +
> +	iounmap(base);
> +
> +	return PTR_ERR(clk);
>  }
>  EXPORT_SYMBOL_GPL(mtk_clk_register_plls);
>  
> diff --git a/drivers/clk/mediatek/clk-pll.h
> b/drivers/clk/mediatek/clk-pll.h
> index a889b1e472e7..bf06e44caef9 100644
> --- a/drivers/clk/mediatek/clk-pll.h
> +++ b/drivers/clk/mediatek/clk-pll.h
> @@ -48,9 +48,9 @@ struct mtk_pll_data {
>  	u8 pll_en_bit; /* Assume 0, indicates BIT(0) by default */
>  };
>  
> -void mtk_clk_register_plls(struct device_node *node,
> -			   const struct mtk_pll_data *plls, int
> num_plls,
> -			   struct clk_onecell_data *clk_data);
> +int mtk_clk_register_plls(struct device_node *node,
> +			  const struct mtk_pll_data *plls, int
> num_plls,
> +			  struct clk_onecell_data *clk_data);
>  void mtk_clk_unregister_plls(const struct mtk_pll_data *plls, int
> num_plls,
>  			     struct clk_onecell_data *clk_data);
>  

Re: [PATCH v3 25/31] clk: mediatek: pll: Implement error handling in register API
Posted by Stephen Boyd 2 years, 9 months ago
Quoting Chen-Yu Tsai (2022-02-08 04:40:28)
> The pll clk type registration function does not stop or return errors
> if any clk failed to be registered, nor does it implement an error
> handling path. This may result in a partially working device if any
> step failed.
> 
> Make the register function return proper error codes, and bail out if
> errors occur. Proper cleanup, i.e. unregister any clks that were
> successfully registered, and unmap the I/O space, is done in the new
> error path.
> 
> Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
> Reviewed-by: Miles Chen <miles.chen@mediatek.com>
> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> ---

Applied to clk-next