[PATCH 0/3] tmio: let platforms decide upon write-protection availability

[PATCH 0/3] tmio: let platforms decide upon write-protection availability

[Guennadi Liakhovetski]

Some platforms and card-formats do not have a write-protect detection. Let 
tmio_mmc users switch WP-detection off, if desired, switch it off for the 
micro-SD slot on the kfr2r09 SuperH board.

Thanks
Guennadi
---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/

[PATCH 1/3] tmio: add a platform flag to disable card write-protection detection

[Guennadi Liakhovetski]

Write-protection status is not always available, e.g., micro-SD cards do not
have a write-protection switch at all. This patch adds a flag to let platforms
force tmio_mmc to consider the card writable.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---
 drivers/mmc/host/tmio_mmc.c |    5 ++++-
 include/linux/mfd/tmio.h    |    4 ++++
 2 files changed, 8 insertions(+), 1 deletions(-)

diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
index 7e79ba4..11c19b0 100644
--- a/drivers/mmc/host/tmio_mmc.c
+++ b/drivers/mmc/host/tmio_mmc.c
@@ -640,8 +640,11 @@ static void tmio_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 static int tmio_mmc_get_ro(struct mmc_host *mmc)
 {
 	struct tmio_mmc_host *host = mmc_priv(mmc);
+	struct mfd_cell	*cell = host->pdev->dev.platform_data;
+	struct tmio_mmc_data *pdata = cell->driver_data;
 
-	return (sd_ctrl_read32(host, CTL_STATUS) & TMIO_STAT_WRPROTECT) ? 0 : 1;
+	return ((pdata->flags & TMIO_MMC_WRPROTECT_DISABLE) ||
+		(sd_ctrl_read32(host, CTL_STATUS) & TMIO_STAT_WRPROTECT)) ? 0 : 1;
 }
 
 static const struct mmc_host_ops tmio_mmc_ops = {
diff --git a/include/linux/mfd/tmio.h b/include/linux/mfd/tmio.h
index 360fc95..feeed0b 100644
--- a/include/linux/mfd/tmio.h
+++ b/include/linux/mfd/tmio.h
@@ -50,6 +50,9 @@
 		tmio_iowrite16((val) >> 16, (base) + ((reg + 2) << (shift))); \
 	} while (0)
 
+/* tmio MMC platform flags */
+#define TMIO_MMC_WRPROTECT_DISABLE	(1 << 0)
+
 int tmio_core_mmc_enable(void __iomem *cnf, int shift, unsigned long base);
 int tmio_core_mmc_resume(void __iomem *cnf, int shift, unsigned long base);
 void tmio_core_mmc_pwr(void __iomem *cnf, int shift, int state);
@@ -66,6 +69,7 @@ struct tmio_mmc_dma {
 struct tmio_mmc_data {
 	unsigned int			hclk;
 	unsigned long			capabilities;
+	unsigned long			flags;
 	struct tmio_mmc_dma		*dma;
 	void (*set_pwr)(struct platform_device *host, int state);
 	void (*set_clk_div)(struct platform_device *host, int state);
-- 
1.6.2.4

[PATCH 2/3] mfd: pass platform flags down to the tmio_mmc driver

[Guennadi Liakhovetski]

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---
 drivers/mfd/sh_mobile_sdhi.c       |    1 +
 include/linux/mfd/sh_mobile_sdhi.h |    1 +
 2 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/drivers/mfd/sh_mobile_sdhi.c b/drivers/mfd/sh_mobile_sdhi.c
index dafa988..d977982 100644
--- a/drivers/mfd/sh_mobile_sdhi.c
+++ b/drivers/mfd/sh_mobile_sdhi.c
@@ -106,6 +106,7 @@ static int __init sh_mobile_sdhi_probe(struct platform_device *pdev)
 	mmc_data->hclk = clk_get_rate(priv->clk);
 	mmc_data->set_pwr = sh_mobile_sdhi_set_pwr;
 	mmc_data->capabilities = MMC_CAP_MMC_HIGHSPEED;
+	mmc_data->flags = p->tmio_flags;
 
 	if (p && p->dma_slave_tx >= 0 && p->dma_slave_rx >= 0) {
 		priv->param_tx.slave_id = p->dma_slave_tx;
diff --git a/include/linux/mfd/sh_mobile_sdhi.h b/include/linux/mfd/sh_mobile_sdhi.h
index c305461..c7b47f8 100644
--- a/include/linux/mfd/sh_mobile_sdhi.h
+++ b/include/linux/mfd/sh_mobile_sdhi.h
@@ -4,6 +4,7 @@
 struct sh_mobile_sdhi_info {
 	int dma_slave_tx;
 	int dma_slave_rx;
+	unsigned long tmio_flags;
 	void (*set_pwr)(struct platform_device *pdev, int state);
 };
 
-- 
1.6.2.4

[PATCH 3/3] sh: disable SD-card write-protection detection on kfr2r09

[Guennadi Liakhovetski]

kfr2r09 board has a micro-SD card slot, therefore card write-protection
detection cannot work there, disable it.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---
 arch/sh/boards/mach-kfr2r09/setup.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/sh/boards/mach-kfr2r09/setup.c b/arch/sh/boards/mach-kfr2r09/setup.c
index 95850aa..68994a1 100644
--- a/arch/sh/boards/mach-kfr2r09/setup.c
+++ b/arch/sh/boards/mach-kfr2r09/setup.c
@@ -11,6 +11,7 @@
 #include <linux/platform_device.h>
 #include <linux/interrupt.h>
 #include <linux/mfd/sh_mobile_sdhi.h>
+#include <linux/mfd/tmio.h>
 #include <linux/mtd/physmap.h>
 #include <linux/mtd/onenand.h>
 #include <linux/delay.h>
@@ -358,8 +359,9 @@ static struct resource kfr2r09_sh_sdhi0_resources[] = {
 };
 
 static struct sh_mobile_sdhi_info sh7724_sdhi0_data = {
-	.dma_slave_tx = SHDMA_SLAVE_SDHI0_TX,
-	.dma_slave_rx = SHDMA_SLAVE_SDHI0_RX,
+	.dma_slave_tx	= SHDMA_SLAVE_SDHI0_TX,
+	.dma_slave_rx	= SHDMA_SLAVE_SDHI0_RX,
+	.tmio_flags	= TMIO_MMC_WRPROTECT_DISABLE,
 };
 
 static struct platform_device kfr2r09_sh_sdhi0_device = {
-- 
1.6.2.4

Re: [PATCH 1/3] tmio: add a platform flag to disable card write-protection detection

[Magnus Damm]

Hi Guennadi,

Many thanks for your work on this!

On Tue, May 11, 2010 at 6:52 PM, Guennadi Liakhovetski
<g.liakhovetski@gmx.de> wrote:
> Write-protection status is not always available, e.g., micro-SD cards do not
> have a write-protection switch at all. This patch adds a flag to let platforms
> force tmio_mmc to consider the card writable.
>
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
> ---
>  drivers/mmc/host/tmio_mmc.c |    5 ++++-
>  include/linux/mfd/tmio.h    |    4 ++++
>  2 files changed, 8 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
> index 7e79ba4..11c19b0 100644
> --- a/drivers/mmc/host/tmio_mmc.c
> +++ b/drivers/mmc/host/tmio_mmc.c
> @@ -640,8 +640,11 @@ static void tmio_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
>  static int tmio_mmc_get_ro(struct mmc_host *mmc)
>  {
>        struct tmio_mmc_host *host = mmc_priv(mmc);
> +       struct mfd_cell *cell = host->pdev->dev.platform_data;
> +       struct tmio_mmc_data *pdata = cell->driver_data;
>
> -       return (sd_ctrl_read32(host, CTL_STATUS) & TMIO_STAT_WRPROTECT) ? 0 : 1;
> +       return ((pdata->flags & TMIO_MMC_WRPROTECT_DISABLE) ||
> +               (sd_ctrl_read32(host, CTL_STATUS) & TMIO_STAT_WRPROTECT)) ? 0 : 1;
>  }

It's a bit late so perhaps I'm thinking backwards, but isn't this
logic inverted?

Fact: The WP signal is missing from the micro-sd slot on the kfr2r09
board, and the card incorrectly comes up write protected.

Solution: TMIO_MMC_WRPROTECT_DISABLE is set to make sure the card is
_not_ write protected by mistake.

But: The code using the ->reg_ro() callback assumes that the card is
read-only if 1 is returned according to drivers/mmc/core/sd.c. The
code above returns 1 if TMIO_MMC_WRPROTECT_DISABLE is set. So the card
will be forced read-only on kfr2r09 unless i'm mistaken, and this does
not help so much. =)

This seems backwards to me. Can you please double check?

/ magnus

Re: [PATCH 1/3] tmio: add a platform flag to disable card write-protection detection

[Guennadi Liakhovetski]

On Tue, 11 May 2010, Magnus Damm wrote:

> Hi Guennadi,
> 
> Many thanks for your work on this!
> 
> On Tue, May 11, 2010 at 6:52 PM, Guennadi Liakhovetski
> <g.liakhovetski@gmx.de> wrote:
> > Write-protection status is not always available, e.g., micro-SD cards do not
> > have a write-protection switch at all. This patch adds a flag to let platforms
> > force tmio_mmc to consider the card writable.
> >
> > Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
> > ---
> >  drivers/mmc/host/tmio_mmc.c |    5 ++++-
> >  include/linux/mfd/tmio.h    |    4 ++++
> >  2 files changed, 8 insertions(+), 1 deletions(-)
> >
> > diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
> > index 7e79ba4..11c19b0 100644
> > --- a/drivers/mmc/host/tmio_mmc.c
> > +++ b/drivers/mmc/host/tmio_mmc.c
> > @@ -640,8 +640,11 @@ static void tmio_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> >  static int tmio_mmc_get_ro(struct mmc_host *mmc)
> >  {
> >        struct tmio_mmc_host *host = mmc_priv(mmc);
> > +       struct mfd_cell *cell = host->pdev->dev.platform_data;
> > +       struct tmio_mmc_data *pdata = cell->driver_data;
> >
> > -       return (sd_ctrl_read32(host, CTL_STATUS) & TMIO_STAT_WRPROTECT) ? 0 : 1;
> > +       return ((pdata->flags & TMIO_MMC_WRPROTECT_DISABLE) ||
> > +               (sd_ctrl_read32(host, CTL_STATUS) & TMIO_STAT_WRPROTECT)) ? 0 : 1;
> >  }
> 
> It's a bit late so perhaps I'm thinking backwards, but isn't this
> logic inverted?
> 
> Fact: The WP signal is missing from the micro-sd slot on the kfr2r09
> board, and the card incorrectly comes up write protected.
> 
> Solution: TMIO_MMC_WRPROTECT_DISABLE is set to make sure the card is
> _not_ write protected by mistake.
> 
> But: The code using the ->reg_ro() callback assumes that the card is
> read-only if 1 is returned according to drivers/mmc/core/sd.c. The
> code above returns 1 if TMIO_MMC_WRPROTECT_DISABLE is set. So the card
> will be forced read-only on kfr2r09 unless i'm mistaken, and this does
> not help so much. =)

I think above is right, please, look again. If TMIO_MMC_WRPROTECT_DISABLE 
is set, the function returns 0.

> This seems backwards to me. Can you please double check?

Thanks
Guennadi
---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/

Re: [PATCH 1/3] tmio: add a platform flag to disable card write-protection detection

[Magnus Damm]

On Tue, May 11, 2010 at 9:15 PM, Guennadi Liakhovetski
<g.liakhovetski@gmx.de> wrote:
> On Tue, 11 May 2010, Magnus Damm wrote:
>
>> Hi Guennadi,
>>
>> Many thanks for your work on this!
>>
>> On Tue, May 11, 2010 at 6:52 PM, Guennadi Liakhovetski
>> <g.liakhovetski@gmx.de> wrote:
>> > Write-protection status is not always available, e.g., micro-SD cards do not
>> > have a write-protection switch at all. This patch adds a flag to let platforms
>> > force tmio_mmc to consider the card writable.
>> >
>> > Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
>> > ---
>> >  drivers/mmc/host/tmio_mmc.c |    5 ++++-
>> >  include/linux/mfd/tmio.h    |    4 ++++
>> >  2 files changed, 8 insertions(+), 1 deletions(-)
>> >
>> > diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
>> > index 7e79ba4..11c19b0 100644
>> > --- a/drivers/mmc/host/tmio_mmc.c
>> > +++ b/drivers/mmc/host/tmio_mmc.c
>> > @@ -640,8 +640,11 @@ static void tmio_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
>> >  static int tmio_mmc_get_ro(struct mmc_host *mmc)
>> >  {
>> >        struct tmio_mmc_host *host = mmc_priv(mmc);
>> > +       struct mfd_cell *cell = host->pdev->dev.platform_data;
>> > +       struct tmio_mmc_data *pdata = cell->driver_data;
>> >
>> > -       return (sd_ctrl_read32(host, CTL_STATUS) & TMIO_STAT_WRPROTECT) ? 0 : 1;
>> > +       return ((pdata->flags & TMIO_MMC_WRPROTECT_DISABLE) ||
>> > +               (sd_ctrl_read32(host, CTL_STATUS) & TMIO_STAT_WRPROTECT)) ? 0 : 1;
>> >  }
>>
>> It's a bit late so perhaps I'm thinking backwards, but isn't this
>> logic inverted?
>>
>> Fact: The WP signal is missing from the micro-sd slot on the kfr2r09
>> board, and the card incorrectly comes up write protected.
>>
>> Solution: TMIO_MMC_WRPROTECT_DISABLE is set to make sure the card is
>> _not_ write protected by mistake.
>>
>> But: The code using the ->reg_ro() callback assumes that the card is
>> read-only if 1 is returned according to drivers/mmc/core/sd.c. The
>> code above returns 1 if TMIO_MMC_WRPROTECT_DISABLE is set. So the card
>> will be forced read-only on kfr2r09 unless i'm mistaken, and this does
>> not help so much. =)
>
> I think above is right, please, look again. If TMIO_MMC_WRPROTECT_DISABLE
> is set, the function returns 0.

Err, yeah, you are correct. I overlooked the "?" part... Looking good!

Thanks,

/ magnus

[PATCH 2/3 v2] mfd: pass platform flags down to the tmio_mmc driver

[Guennadi Liakhovetski]

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---

v1 -> v2:

it's better without a NULL dereference

 drivers/mfd/sh_mobile_sdhi.c       |    2 ++
 include/linux/mfd/sh_mobile_sdhi.h |    1 +
 2 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/drivers/mfd/sh_mobile_sdhi.c b/drivers/mfd/sh_mobile_sdhi.c
index dafa988..7970fe8 100644
--- a/drivers/mfd/sh_mobile_sdhi.c
+++ b/drivers/mfd/sh_mobile_sdhi.c
@@ -106,6 +106,8 @@ static int __init sh_mobile_sdhi_probe(struct platform_device *pdev)
 	mmc_data->hclk = clk_get_rate(priv->clk);
 	mmc_data->set_pwr = sh_mobile_sdhi_set_pwr;
 	mmc_data->capabilities = MMC_CAP_MMC_HIGHSPEED;
+	if (p)
+		mmc_data->flags = p->tmio_flags;
 
 	if (p && p->dma_slave_tx >= 0 && p->dma_slave_rx >= 0) {
 		priv->param_tx.slave_id = p->dma_slave_tx;
diff --git a/include/linux/mfd/sh_mobile_sdhi.h b/include/linux/mfd/sh_mobile_sdhi.h
index c305461..c7b47f8 100644
--- a/include/linux/mfd/sh_mobile_sdhi.h
+++ b/include/linux/mfd/sh_mobile_sdhi.h
@@ -4,6 +4,7 @@
 struct sh_mobile_sdhi_info {
 	int dma_slave_tx;
 	int dma_slave_rx;
+	unsigned long tmio_flags;
 	void (*set_pwr)(struct platform_device *pdev, int state);
 };
 
-- 
1.6.2.4

[PATCH 1/3] tmio: add a platform flag to disable card write-protection detection

[Guennadi Liakhovetski]

Write-protection status is not always available, e.g., micro-SD cards do not
have a write-protection switch at all. This patch adds a flag to let platforms
force tmio_mmc to consider the card writable.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Ian Molton <ian@mnementh.co.uk>
---
 drivers/mmc/host/tmio_mmc.c |    5 ++++-
 include/linux/mfd/tmio.h    |    4 ++++
 2 files changed, 8 insertions(+), 1 deletions(-)

diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
index 7e79ba4..11c19b0 100644
--- a/drivers/mmc/host/tmio_mmc.c
+++ b/drivers/mmc/host/tmio_mmc.c
@@ -640,8 +640,11 @@ static void tmio_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 static int tmio_mmc_get_ro(struct mmc_host *mmc)
 {
 	struct tmio_mmc_host *host = mmc_priv(mmc);
+	struct mfd_cell	*cell = host->pdev->dev.platform_data;
+	struct tmio_mmc_data *pdata = cell->driver_data;
 
-	return (sd_ctrl_read32(host, CTL_STATUS) & TMIO_STAT_WRPROTECT) ? 0 : 1;
+	return ((pdata->flags & TMIO_MMC_WRPROTECT_DISABLE) ||
+		(sd_ctrl_read32(host, CTL_STATUS) & TMIO_STAT_WRPROTECT)) ? 0 : 1;
 }
 
 static const struct mmc_host_ops tmio_mmc_ops = {
diff --git a/include/linux/mfd/tmio.h b/include/linux/mfd/tmio.h
index 360fc95..feeed0b 100644
--- a/include/linux/mfd/tmio.h
+++ b/include/linux/mfd/tmio.h
@@ -50,6 +50,9 @@
 		tmio_iowrite16((val) >> 16, (base) + ((reg + 2) << (shift))); \
 	} while (0)
 
+/* tmio MMC platform flags */
+#define TMIO_MMC_WRPROTECT_DISABLE	(1 << 0)
+
 int tmio_core_mmc_enable(void __iomem *cnf, int shift, unsigned long base);
 int tmio_core_mmc_resume(void __iomem *cnf, int shift, unsigned long base);
 void tmio_core_mmc_pwr(void __iomem *cnf, int shift, int state);
@@ -66,6 +69,7 @@ struct tmio_mmc_dma {
 struct tmio_mmc_data {
 	unsigned int			hclk;
 	unsigned long			capabilities;
+	unsigned long			flags;
 	struct tmio_mmc_dma		*dma;
 	void (*set_pwr)(struct platform_device *host, int state);
 	void (*set_clk_div)(struct platform_device *host, int state);
-- 
1.6.2.4