[2/2] ARM: dts: igep0020: Add SD card write-protect pin.
diff mbox

Message ID 1462568554-7868-2-git-send-email-enric.balletbo@collabora.com
State New
Headers show

Commit Message

Enric Balletbo i Serra May 6, 2016, 9:02 p.m. UTC
A host device that supports write protection should refuse to write to
an SD card that is designated read-only when write-protect is set. This
is an optional feature of the SD specification.

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
---
 arch/arm/boot/dts/omap3-igep0020-common.dtsi | 11 +++++++++++
 1 file changed, 11 insertions(+)

Comments

Javier Martinez Canillas May 6, 2016, 9:07 p.m. UTC | #1
Hello Enric,

On Fri, May 6, 2016 at 5:02 PM, Enric Balletbo i Serra
<enric.balletbo@collabora.com> wrote:
> A host device that supports write protection should refuse to write to
> an SD card that is designated read-only when write-protect is set. This
> is an optional feature of the SD specification.
>
> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
> ---

Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>

Best regards,
Javier
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Ladislav Michl May 13, 2016, 12:37 p.m. UTC | #2
Hi Enric!

On Fri, May 06, 2016 at 11:02:34PM +0200, Enric Balletbo i Serra wrote:
> A host device that supports write protection should refuse to write to
> an SD card that is designated read-only when write-protect is set. This
> is an optional feature of the SD specification.

Does it ever work on any IGEPv2? I have similar patch in my repo and there
is no difference when enabling write protection on SD card. Also schemantics
shows GPIO29 constantly pulled up with a resistor. Is there any board
revision with working WP? I'm just curious as patch is of course correct.

Best regards,
	ladis

> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
> ---
>  arch/arm/boot/dts/omap3-igep0020-common.dtsi | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/omap3-igep0020-common.dtsi b/arch/arm/boot/dts/omap3-igep0020-common.dtsi
> index d6f839c..b697106 100644
> --- a/arch/arm/boot/dts/omap3-igep0020-common.dtsi
> +++ b/arch/arm/boot/dts/omap3-igep0020-common.dtsi
> @@ -194,6 +194,12 @@
>  			OMAP3630_CORE2_IOPAD(0x25f8, PIN_OUTPUT | MUX_MODE4) /* etk_d14.gpio_28 */
>  		>;
>  	};
> +
> +	mmc1_wp_pins: pinmux_mmc1_cd_pins {
> +		pinctrl-single,pins = <
> +			OMAP3630_CORE2_IOPAD(0x25fa, PIN_INPUT | MUX_MODE4)   /* etk_d15.gpio_29 */
> +		>;
> +	};
>  };
>  
>  &i2c3 {
> @@ -250,3 +256,8 @@
>  		};
>  	};
>  };
> +
> +&mmc1 {
> +	pinctrl-0 = <&mmc1_pins &mmc1_wp_pins>;
> +	wp-gpios = <&gpio1 29 GPIO_ACTIVE_LOW>;	/* gpio_29 */
> +};
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Enric Balletbo Serra May 17, 2016, 8:06 a.m. UTC | #3
Hi Ladislav,

2016-05-13 14:37 GMT+02:00 Ladislav Michl <ladis@linux-mips.org>:
> Hi Enric!
>
> On Fri, May 06, 2016 at 11:02:34PM +0200, Enric Balletbo i Serra wrote:
>> A host device that supports write protection should refuse to write to
>> an SD card that is designated read-only when write-protect is set. This
>> is an optional feature of the SD specification.
>
> Does it ever work on any IGEPv2? I have similar patch in my repo and there
> is no difference when enabling write protection on SD card. Also schemantics
> shows GPIO29 constantly pulled up with a resistor. Is there any board
> revision with working WP? I'm just curious as patch is of course correct.
>

Note that the microSD formats do not support a write protection
switch, a host device that supports write protection should refuse to
write to an SD card that is designated read-only in this way, which is
an optional feature of the SD specification. As far as I know there is
only a use case for the IGEPv2, the TP close to the SD card can be
used as a write-protection switch, this is not an usual use case and
of course, this needs some wiring, but it's a feature used by someone.

> Best regards,
>         ladis
>
>> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
>> ---
>>  arch/arm/boot/dts/omap3-igep0020-common.dtsi | 11 +++++++++++
>>  1 file changed, 11 insertions(+)
>>
>> diff --git a/arch/arm/boot/dts/omap3-igep0020-common.dtsi b/arch/arm/boot/dts/omap3-igep0020-common.dtsi
>> index d6f839c..b697106 100644
>> --- a/arch/arm/boot/dts/omap3-igep0020-common.dtsi
>> +++ b/arch/arm/boot/dts/omap3-igep0020-common.dtsi
>> @@ -194,6 +194,12 @@
>>                       OMAP3630_CORE2_IOPAD(0x25f8, PIN_OUTPUT | MUX_MODE4) /* etk_d14.gpio_28 */
>>               >;
>>       };
>> +
>> +     mmc1_wp_pins: pinmux_mmc1_cd_pins {
>> +             pinctrl-single,pins = <
>> +                     OMAP3630_CORE2_IOPAD(0x25fa, PIN_INPUT | MUX_MODE4)   /* etk_d15.gpio_29 */
>> +             >;
>> +     };
>>  };
>>
>>  &i2c3 {
>> @@ -250,3 +256,8 @@
>>               };
>>       };
>>  };
>> +
>> +&mmc1 {
>> +     pinctrl-0 = <&mmc1_pins &mmc1_wp_pins>;
>> +     wp-gpios = <&gpio1 29 GPIO_ACTIVE_LOW>; /* gpio_29 */
>> +};
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Patch
diff mbox

diff --git a/arch/arm/boot/dts/omap3-igep0020-common.dtsi b/arch/arm/boot/dts/omap3-igep0020-common.dtsi
index d6f839c..b697106 100644
--- a/arch/arm/boot/dts/omap3-igep0020-common.dtsi
+++ b/arch/arm/boot/dts/omap3-igep0020-common.dtsi
@@ -194,6 +194,12 @@ 
 			OMAP3630_CORE2_IOPAD(0x25f8, PIN_OUTPUT | MUX_MODE4) /* etk_d14.gpio_28 */
 		>;
 	};
+
+	mmc1_wp_pins: pinmux_mmc1_cd_pins {
+		pinctrl-single,pins = <
+			OMAP3630_CORE2_IOPAD(0x25fa, PIN_INPUT | MUX_MODE4)   /* etk_d15.gpio_29 */
+		>;
+	};
 };
 
 &i2c3 {
@@ -250,3 +256,8 @@ 
 		};
 	};
 };
+
+&mmc1 {
+	pinctrl-0 = <&mmc1_pins &mmc1_wp_pins>;
+	wp-gpios = <&gpio1 29 GPIO_ACTIVE_LOW>;	/* gpio_29 */
+};