On HP laptops with JMicron 388 chip, the write-locked SD card isn't
detected correctly as read-only in many cases. This is because the
PRESENT_STATE register becomes unsable just after plugging, and it
returns the WRITE_PROTECT bit wrongly at the first read.
This patch fixes the read-only detection by adding the own get_ro op
for checking the register more intensively with a relatively long
delay.
The patch is tested with 2.6.39-rc4 kernel.
Cc: Aries Lee <[email protected]>
Signed-off-by: Takashi Iwai <[email protected]>
---
drivers/mmc/host/sdhci-pci.c | 34 ++++++++++++++++++++++++++++++++++
1 files changed, 34 insertions(+), 0 deletions(-)
diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c
index a136be7..9037b2a 100644
--- a/drivers/mmc/host/sdhci-pci.c
+++ b/drivers/mmc/host/sdhci-pci.c
@@ -346,6 +346,35 @@ static void jmicron_enable_mmc(struct sdhci_host *host, int on)
writeb(scratch, host->ioaddr + 0xC0);
}
+/* As PRESENT_STATE register becomes unstable just after plugging,
+ * need to check the RO-cap multiple times with a relatively long delay.
+ */
+
+#define SAMPLE_COUNT 5
+
+static unsigned int jmicron_get_ro(struct sdhci_host *host)
+{
+ int i, ro_count;
+
+ ro_count = 0;
+ for (i = 0; i < SAMPLE_COUNT; i++) {
+ int present = sdhci_readl(host, SDHCI_PRESENT_STATE);
+ if (!(present & SDHCI_WRITE_PROTECT)) {
+ if (++ro_count > SAMPLE_COUNT / 2)
+ return 1;
+ }
+ msleep(30);
+ }
+ return 0;
+}
+
+static int sdhci_pci_enable_dma(struct sdhci_host *host);
+
+static struct sdhci_ops jmicron_pci_ops = {
+ .enable_dma = sdhci_pci_enable_dma,
+ .get_ro = jmicron_get_ro,
+};
+
static int jmicron_probe_slot(struct sdhci_pci_slot *slot)
{
if (slot->chip->pdev->revision == 0) {
@@ -383,6 +412,11 @@ static int jmicron_probe_slot(struct sdhci_pci_slot *slot)
slot->host->mmc->caps |= MMC_CAP_BUS_WIDTH_TEST;
+ /* Replace the ops for unstable get_ro detection */
+ if (slot->chip->pdev->device == PCI_DEVICE_ID_JMICRON_JMB388_SD ||
+ slot->chip->pdev->device == PCI_DEVICE_ID_JMICRON_JMB388_ESD)
+ slot->host->ops = &jmicron_pci_ops;
+
return 0;
}
--
1.7.4.2
Hi Takashi,
On Thu, Apr 21 2011, Takashi Iwai wrote:
> On HP laptops with JMicron 388 chip, the write-locked SD card isn't
> detected correctly as read-only in many cases. This is because the
> PRESENT_STATE register becomes unsable just after plugging, and it
> returns the WRITE_PROTECT bit wrongly at the first read.
>
> This patch fixes the read-only detection by adding the own get_ro op
> for checking the register more intensively with a relatively long
> delay.
>
> The patch is tested with 2.6.39-rc4 kernel.
>
> Cc: Aries Lee <[email protected]>
> Signed-off-by: Takashi Iwai <[email protected]>
> ---
> drivers/mmc/host/sdhci-pci.c | 34 ++++++++++++++++++++++++++++++++++
> 1 files changed, 34 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c
> index a136be7..9037b2a 100644
> --- a/drivers/mmc/host/sdhci-pci.c
> +++ b/drivers/mmc/host/sdhci-pci.c
> @@ -346,6 +346,35 @@ static void jmicron_enable_mmc(struct sdhci_host *host, int on)
> writeb(scratch, host->ioaddr + 0xC0);
> }
>
> +/* As PRESENT_STATE register becomes unstable just after plugging,
> + * need to check the RO-cap multiple times with a relatively long delay.
> + */
> +
> +#define SAMPLE_COUNT 5
> +
> +static unsigned int jmicron_get_ro(struct sdhci_host *host)
> +{
> + int i, ro_count;
> +
> + ro_count = 0;
> + for (i = 0; i < SAMPLE_COUNT; i++) {
> + int present = sdhci_readl(host, SDHCI_PRESENT_STATE);
> + if (!(present & SDHCI_WRITE_PROTECT)) {
> + if (++ro_count > SAMPLE_COUNT / 2)
> + return 1;
> + }
> + msleep(30);
> + }
> + return 0;
> +}
> +
> +static int sdhci_pci_enable_dma(struct sdhci_host *host);
> +
> +static struct sdhci_ops jmicron_pci_ops = {
> + .enable_dma = sdhci_pci_enable_dma,
> + .get_ro = jmicron_get_ro,
> +};
> +
> static int jmicron_probe_slot(struct sdhci_pci_slot *slot)
> {
> if (slot->chip->pdev->revision == 0) {
> @@ -383,6 +412,11 @@ static int jmicron_probe_slot(struct sdhci_pci_slot *slot)
>
> slot->host->mmc->caps |= MMC_CAP_BUS_WIDTH_TEST;
>
> + /* Replace the ops for unstable get_ro detection */
> + if (slot->chip->pdev->device == PCI_DEVICE_ID_JMICRON_JMB388_SD ||
> + slot->chip->pdev->device == PCI_DEVICE_ID_JMICRON_JMB388_ESD)
> + slot->host->ops = &jmicron_pci_ops;
> +
> return 0;
> }
I don't like overwriting ops here -- it's too magical, and now we have
to maintain the ops table in two places. A quirk seems justified here,
even though we're trying to reduce them in general. Can anyone find a
better solution?
Thanks,
- Chris.
--
Chris Ball <[email protected]> <http://printf.net/>
One Laptop Per Child
At Thu, 21 Apr 2011 12:40:26 -0400,
Chris Ball wrote:
>
> Hi Takashi,
>
> On Thu, Apr 21 2011, Takashi Iwai wrote:
> > On HP laptops with JMicron 388 chip, the write-locked SD card isn't
> > detected correctly as read-only in many cases. This is because the
> > PRESENT_STATE register becomes unsable just after plugging, and it
> > returns the WRITE_PROTECT bit wrongly at the first read.
> >
> > This patch fixes the read-only detection by adding the own get_ro op
> > for checking the register more intensively with a relatively long
> > delay.
> >
> > The patch is tested with 2.6.39-rc4 kernel.
> >
> > Cc: Aries Lee <[email protected]>
> > Signed-off-by: Takashi Iwai <[email protected]>
> > ---
> > drivers/mmc/host/sdhci-pci.c | 34 ++++++++++++++++++++++++++++++++++
> > 1 files changed, 34 insertions(+), 0 deletions(-)
> >
> > diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c
> > index a136be7..9037b2a 100644
> > --- a/drivers/mmc/host/sdhci-pci.c
> > +++ b/drivers/mmc/host/sdhci-pci.c
> > @@ -346,6 +346,35 @@ static void jmicron_enable_mmc(struct sdhci_host *host, int on)
> > writeb(scratch, host->ioaddr + 0xC0);
> > }
> >
> > +/* As PRESENT_STATE register becomes unstable just after plugging,
> > + * need to check the RO-cap multiple times with a relatively long delay.
> > + */
> > +
> > +#define SAMPLE_COUNT 5
> > +
> > +static unsigned int jmicron_get_ro(struct sdhci_host *host)
> > +{
> > + int i, ro_count;
> > +
> > + ro_count = 0;
> > + for (i = 0; i < SAMPLE_COUNT; i++) {
> > + int present = sdhci_readl(host, SDHCI_PRESENT_STATE);
> > + if (!(present & SDHCI_WRITE_PROTECT)) {
> > + if (++ro_count > SAMPLE_COUNT / 2)
> > + return 1;
> > + }
> > + msleep(30);
> > + }
> > + return 0;
> > +}
> > +
> > +static int sdhci_pci_enable_dma(struct sdhci_host *host);
> > +
> > +static struct sdhci_ops jmicron_pci_ops = {
> > + .enable_dma = sdhci_pci_enable_dma,
> > + .get_ro = jmicron_get_ro,
> > +};
> > +
> > static int jmicron_probe_slot(struct sdhci_pci_slot *slot)
> > {
> > if (slot->chip->pdev->revision == 0) {
> > @@ -383,6 +412,11 @@ static int jmicron_probe_slot(struct sdhci_pci_slot *slot)
> >
> > slot->host->mmc->caps |= MMC_CAP_BUS_WIDTH_TEST;
> >
> > + /* Replace the ops for unstable get_ro detection */
> > + if (slot->chip->pdev->device == PCI_DEVICE_ID_JMICRON_JMB388_SD ||
> > + slot->chip->pdev->device == PCI_DEVICE_ID_JMICRON_JMB388_ESD)
> > + slot->host->ops = &jmicron_pci_ops;
> > +
> > return 0;
> > }
>
> I don't like overwriting ops here -- it's too magical, and now we have
> to maintain the ops table in two places. A quirk seems justified here,
> even though we're trying to reduce them in general.
Well, I also used quirk bit in my very first version I worked for
2.6.32 kernel. But when I looked at 2.6.39, quirks are almost full --
only the last one bit is left for bit 31. So I didn't want to finish
it :)
> Can anyone find a better solution?
One way would be to copy the ops table itself in struct sdhci_host
instead of keeping the ops table pointer. Then you can overwrite only
the specific op in each probe_slot callback.
thanks,
Takashi
Hi Takashi,
On Thu, Apr 21 2011, Takashi Iwai wrote:
>> I don't like overwriting ops here -- it's too magical, and now we have
>> to maintain the ops table in two places. A quirk seems justified here,
>> even though we're trying to reduce them in general.
>
> Well, I also used quirk bit in my very first version I worked for
> 2.6.32 kernel. But when I looked at 2.6.39, quirks are almost full --
> only the last one bit is left for bit 31. So I didn't want to finish
> it :)
>
>> Can anyone find a better solution?
>
> One way would be to copy the ops table itself in struct sdhci_host
> instead of keeping the ops table pointer. Then you can overwrite only
> the specific op in each probe_slot callback.
I think I'd rather not touch ops at all and keep the code simple --
if you don't mind, please post a version with quirks, and I'll work
on freeing up a few bits.
Thanks,
- Chris.
--
Chris Ball <[email protected]> <http://printf.net/>
One Laptop Per Child
At Thu, 21 Apr 2011 13:36:03 -0400,
Chris Ball wrote:
>
> Hi Takashi,
>
> On Thu, Apr 21 2011, Takashi Iwai wrote:
> >> I don't like overwriting ops here -- it's too magical, and now we have
> >> to maintain the ops table in two places. A quirk seems justified here,
> >> even though we're trying to reduce them in general.
> >
> > Well, I also used quirk bit in my very first version I worked for
> > 2.6.32 kernel. But when I looked at 2.6.39, quirks are almost full --
> > only the last one bit is left for bit 31. So I didn't want to finish
> > it :)
> >
> >> Can anyone find a better solution?
> >
> > One way would be to copy the ops table itself in struct sdhci_host
> > instead of keeping the ops table pointer. Then you can overwrite only
> > the specific op in each probe_slot callback.
>
> I think I'd rather not touch ops at all and keep the code simple --
> if you don't mind, please post a version with quirks, and I'll work
> on freeing up a few bits.
OK, I'll send shortly.
Takashi