[PATCH v5 1/2] mtd: nand: sunxi: update DT bindings

[PATCH v5 1/2] mtd: nand: sunxi: update DT bindings

[Icenowy Zheng]

Document the reset lines

Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
---
Changes since v2:
  - Nothing.

 Documentation/devicetree/bindings/mtd/sunxi-nand.txt | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/mtd/sunxi-nand.txt b/Documentation/devicetree/bindings/mtd/sunxi-nand.txt
index 086d6f4..a328fbb 100644
--- a/Documentation/devicetree/bindings/mtd/sunxi-nand.txt
+++ b/Documentation/devicetree/bindings/mtd/sunxi-nand.txt
@@ -15,6 +15,8 @@ Optional children nodes:
 Children nodes represent the available nand chips.
 
 Optional properties:
+- reset : phandle + reset specifier pair
+- reset-names : must contain "ahb"
 - allwinner,rb : shall contain the native Ready/Busy ids.
  or
 - rb-gpios : shall contain the gpios used as R/B pins.
-- 
2.9.0

[PATCH v5 2/2] mtd: nand: sunxi: add reset line support

[Icenowy Zheng]

The NAND controller on some sun8i chips needs its reset line to be
deasserted before they can enter working state.

Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
---
Changes in v2:
  - Corrected the error checking code of reset line.

Changes in v3:
  - Corrected a more serious error brought in the "fix" of v2.

Changes in v4:
  - Removed unneeded code block after "else".

Changes in v5:
  - Added reassertion code in case of initialization error and device
    remove.

 drivers/mtd/nand/sunxi_nand.c | 27 ++++++++++++++++++++++++---
 1 file changed, 24 insertions(+), 3 deletions(-)

diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
index a83a690..3b40186 100644
--- a/drivers/mtd/nand/sunxi_nand.c
+++ b/drivers/mtd/nand/sunxi_nand.c
@@ -39,6 +39,7 @@
 #include <linux/gpio.h>
 #include <linux/interrupt.h>
 #include <linux/iopoll.h>
+#include <linux/reset.h>
 
 #define NFC_REG_CTL		0x0000
 #define NFC_REG_ST		0x0004
@@ -269,6 +270,7 @@ struct sunxi_nfc {
 	void __iomem *regs;
 	struct clk *ahb_clk;
 	struct clk *mod_clk;
+	struct reset_control *reset;
 	unsigned long assigned_cs;
 	unsigned long clk_rate;
 	struct list_head chips;
@@ -1871,26 +1873,41 @@ static int sunxi_nfc_probe(struct platform_device *pdev)
 	if (ret)
 		goto out_ahb_clk_unprepare;
 
+	nfc->reset = devm_reset_control_get_optional(dev, "ahb");
+
+	if (!IS_ERR(nfc->reset)) {
+		ret = reset_control_deassert(nfc->reset);
+		if (ret) {
+			dev_err(dev, "reset err %d\n", ret);
+			goto out_mod_clk_unprepare;
+		}
+	} else if (PTR_ERR(nfc->reset) != -ENOENT) {
+		return PTR_ERR(nfc->reset);
+	}
+
 	ret = sunxi_nfc_rst(nfc);
 	if (ret)
-		goto out_mod_clk_unprepare;
+		goto out_ahb_reset_reassert;
 
 	writel(0, nfc->regs + NFC_REG_INT);
 	ret = devm_request_irq(dev, irq, sunxi_nfc_interrupt,
 			       0, "sunxi-nand", nfc);
 	if (ret)
-		goto out_mod_clk_unprepare;
+		goto out_ahb_reset_reassert;
 
 	platform_set_drvdata(pdev, nfc);
 
 	ret = sunxi_nand_chips_init(dev, nfc);
 	if (ret) {
 		dev_err(dev, "failed to init nand chips\n");
-		goto out_mod_clk_unprepare;
+		goto out_ahb_reset_reassert;
 	}
 
 	return 0;
 
+out_ahb_reset_reassert:
+	if (!IS_ERR(nfc->reset))
+		reset_control_assert(nfc->reset);
 out_mod_clk_unprepare:
 	clk_disable_unprepare(nfc->mod_clk);
 out_ahb_clk_unprepare:
@@ -1904,6 +1921,10 @@ static int sunxi_nfc_remove(struct platform_device *pdev)
 	struct sunxi_nfc *nfc = platform_get_drvdata(pdev);
 
 	sunxi_nand_chips_cleanup(nfc);
+
+	if (!IS_ERR(nfc->reset))
+		reset_control_assert(nfc->reset);
+
 	clk_disable_unprepare(nfc->mod_clk);
 	clk_disable_unprepare(nfc->ahb_clk);
 
-- 
2.9.0

Re: [PATCH v5 2/2] mtd: nand: sunxi: add reset line support

[Maxime Ripard]

[-- Attachment #1: Type: text/plain, Size: 2025 bytes --]

On Mon, Jun 20, 2016 at 12:14:35AM +0800, Icenowy Zheng wrote:
> The NAND controller on some sun8i chips needs its reset line to be
> deasserted before they can enter working state.
> 
> Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
> ---
> Changes in v2:
>   - Corrected the error checking code of reset line.
> 
> Changes in v3:
>   - Corrected a more serious error brought in the "fix" of v2.
> 
> Changes in v4:
>   - Removed unneeded code block after "else".
> 
> Changes in v5:
>   - Added reassertion code in case of initialization error and device
>     remove.
> 
>  drivers/mtd/nand/sunxi_nand.c | 27 ++++++++++++++++++++++++---
>  1 file changed, 24 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
> index a83a690..3b40186 100644
> --- a/drivers/mtd/nand/sunxi_nand.c
> +++ b/drivers/mtd/nand/sunxi_nand.c
> @@ -39,6 +39,7 @@
>  #include <linux/gpio.h>
>  #include <linux/interrupt.h>
>  #include <linux/iopoll.h>
> +#include <linux/reset.h>
>  
>  #define NFC_REG_CTL		0x0000
>  #define NFC_REG_ST		0x0004
> @@ -269,6 +270,7 @@ struct sunxi_nfc {
>  	void __iomem *regs;
>  	struct clk *ahb_clk;
>  	struct clk *mod_clk;
> +	struct reset_control *reset;
>  	unsigned long assigned_cs;
>  	unsigned long clk_rate;
>  	struct list_head chips;
> @@ -1871,26 +1873,41 @@ static int sunxi_nfc_probe(struct platform_device *pdev)
>  	if (ret)
>  		goto out_ahb_clk_unprepare;
>  
> +	nfc->reset = devm_reset_control_get_optional(dev, "ahb");
> +
> +	if (!IS_ERR(nfc->reset)) {
> +		ret = reset_control_deassert(nfc->reset);
> +		if (ret) {
> +			dev_err(dev, "reset err %d\n", ret);
> +			goto out_mod_clk_unprepare;
> +		}
> +	} else if (PTR_ERR(nfc->reset) != -ENOENT) {
> +		return PTR_ERR(nfc->reset);

You're leaking all the resources here. Please use a goto.

Thanks,
Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 819 bytes --]

Re: [PATCH v5 2/2] mtd: nand: sunxi: add reset line support

[Icenowy Zheng]

You're right. This is a copy-n-paste error from the original sunxi-mmc.c file,
which get all the clocks and resets before using them.

20.06.2016, 03:37, "Maxime Ripard" <maxime.ripard@free-electrons.com>:
> On Mon, Jun 20, 2016 at 12:14:35AM +0800, Icenowy Zheng wrote:
>>  The NAND controller on some sun8i chips needs its reset line to be
>>  deasserted before they can enter working state.
>>
>>  Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
>>  ---
>>  Changes in v2:
>>    - Corrected the error checking code of reset line.
>>
>>  Changes in v3:
>>    - Corrected a more serious error brought in the "fix" of v2.
>>
>>  Changes in v4:
>>    - Removed unneeded code block after "else".
>>
>>  Changes in v5:
>>    - Added reassertion code in case of initialization error and device
>>      remove.
>>
>>   drivers/mtd/nand/sunxi_nand.c | 27 ++++++++++++++++++++++++---
>>   1 file changed, 24 insertions(+), 3 deletions(-)
>>
>>  diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
>>  index a83a690..3b40186 100644
>>  --- a/drivers/mtd/nand/sunxi_nand.c
>>  +++ b/drivers/mtd/nand/sunxi_nand.c
>>  @@ -39,6 +39,7 @@
>>   #include <linux/gpio.h>
>>   #include <linux/interrupt.h>
>>   #include <linux/iopoll.h>
>>  +#include <linux/reset.h>
>>
>>   #define NFC_REG_CTL 0x0000
>>   #define NFC_REG_ST 0x0004
>>  @@ -269,6 +270,7 @@ struct sunxi_nfc {
>>           void __iomem *regs;
>>           struct clk *ahb_clk;
>>           struct clk *mod_clk;
>>  + struct reset_control *reset;
>>           unsigned long assigned_cs;
>>           unsigned long clk_rate;
>>           struct list_head chips;
>>  @@ -1871,26 +1873,41 @@ static int sunxi_nfc_probe(struct platform_device *pdev)
>>           if (ret)
>>                   goto out_ahb_clk_unprepare;
>>
>>  + nfc->reset = devm_reset_control_get_optional(dev, "ahb");
>>  +
>>  + if (!IS_ERR(nfc->reset)) {
>>  + ret = reset_control_deassert(nfc->reset);
>>  + if (ret) {
>>  + dev_err(dev, "reset err %d\n", ret);
>>  + goto out_mod_clk_unprepare;
>>  + }
>>  + } else if (PTR_ERR(nfc->reset) != -ENOENT) {
>>  + return PTR_ERR(nfc->reset);
>
> You're leaking all the resources here. Please use a goto.
>
> Thanks,
> Maxime
>
> --
> Maxime Ripard, Free Electrons
> Embedded Linux, Kernel and Android engineering
> http://free-electrons.com