2022-04-23 08:19:45

by Jonathan Bakker

[permalink] [raw]
Subject: [PATCH 4/5] mtd: onenand: samsung: Make sure that bus clock is enabled

From: Tomasz Figa <[email protected]>

This patch adds basic handling of controller bus clock to make sure that
in device probe it is enabled and device can operate correctly. The
clock is optional and driver behavior is identical as before this patch
if not provided.

Signed-off-by: Tomasz Figa <[email protected]>
Signed-off-by: PaweÅ‚ Chmiel <[email protected]>
Reviewed-by: Miquel Raynal <[email protected]>
Signed-off-by: Jonathan Bakker <[email protected]>
---
drivers/mtd/nand/onenand/onenand_samsung.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/drivers/mtd/nand/onenand/onenand_samsung.c b/drivers/mtd/nand/onenand/onenand_samsung.c
index a3ef4add865a..62014f8d27b6 100644
--- a/drivers/mtd/nand/onenand/onenand_samsung.c
+++ b/drivers/mtd/nand/onenand/onenand_samsung.c
@@ -11,6 +11,7 @@
* S5PC110: use DMA
*/

+#include <linux/clk.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/sched.h>
@@ -122,6 +123,7 @@ enum soc_type {
struct s3c_onenand {
struct mtd_info *mtd;
struct platform_device *pdev;
+ struct clk *clk_bus;
enum soc_type type;
void __iomem *ctrl_base;
void __iomem *chip_base;
@@ -914,6 +916,10 @@ static int s3c_onenand_probe(struct platform_device *pdev)
}
}

+ onenand->clk_bus = devm_clk_get(&pdev->dev, "bus");
+ if (!IS_ERR(onenand->clk_bus))
+ clk_prepare_enable(onenand->clk_bus);
+
err = onenand_scan(mtd, 1);
if (err)
return err;
@@ -945,6 +951,8 @@ static int s3c_onenand_remove(struct platform_device *pdev)
struct mtd_info *mtd = platform_get_drvdata(pdev);

onenand_release(mtd);
+ if (!IS_ERR(onenand->clk_bus))
+ clk_disable_unprepare(onenand->clk_bus);

return 0;
}
--
2.30.2


2022-04-24 15:37:00

by Krzysztof Kozlowski

[permalink] [raw]
Subject: Re: [PATCH 4/5] mtd: onenand: samsung: Make sure that bus clock is enabled

On 23/04/2022 05:46, Jonathan Bakker wrote:
> From: Tomasz Figa <[email protected]>
>
> This patch adds basic handling of controller bus clock to make sure that
> in device probe it is enabled and device can operate correctly. The
> clock is optional and driver behavior is identical as before this patch
> if not provided.
>
> Signed-off-by: Tomasz Figa <[email protected]>
> Signed-off-by: PaweÅ‚ Chmiel <[email protected]>
> Reviewed-by: Miquel Raynal <[email protected]>
> Signed-off-by: Jonathan Bakker <[email protected]>
> ---
> drivers/mtd/nand/onenand/onenand_samsung.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/drivers/mtd/nand/onenand/onenand_samsung.c b/drivers/mtd/nand/onenand/onenand_samsung.c
> index a3ef4add865a..62014f8d27b6 100644
> --- a/drivers/mtd/nand/onenand/onenand_samsung.c
> +++ b/drivers/mtd/nand/onenand/onenand_samsung.c
> @@ -11,6 +11,7 @@
> * S5PC110: use DMA
> */
>
> +#include <linux/clk.h>
> #include <linux/module.h>
> #include <linux/platform_device.h>
> #include <linux/sched.h>
> @@ -122,6 +123,7 @@ enum soc_type {
> struct s3c_onenand {
> struct mtd_info *mtd;
> struct platform_device *pdev;
> + struct clk *clk_bus;
> enum soc_type type;
> void __iomem *ctrl_base;
> void __iomem *chip_base;
> @@ -914,6 +916,10 @@ static int s3c_onenand_probe(struct platform_device *pdev)
> }
> }
>
> + onenand->clk_bus = devm_clk_get(&pdev->dev, "bus");

If it is optional, use optional clk API.

> + if (!IS_ERR(onenand->clk_bus))
> + clk_prepare_enable(onenand->clk_bus);
> +
> err = onenand_scan(mtd, 1);
> if (err)
> return err;

Error paths not updated.

Also what about other clocks?

I propose you should take over the authorship of the patch because it
will be more changes.

> @@ -945,6 +951,8 @@ static int s3c_onenand_remove(struct platform_device *pdev)
> struct mtd_info *mtd = platform_get_drvdata(pdev);
>
> onenand_release(mtd);
> + if (!IS_ERR(onenand->clk_bus))
> + clk_disable_unprepare(onenand->clk_bus);
>
> return 0;
> }


Best regards,
Krzysztof