On 09/30/2010 10:16 AM, Wolfram Sang wrote:
Hi Richard,
On Wed, Sep 29, 2010 at 11:24:25PM +0200, Richard Röjfors wrote:
On 09/29/2010 10:07 PM, Wolfram Sang wrote:
We need to carry some information per host, e.g. the clock. Add a
structure for it and initialize it in the generic part. Also do not use
the parent of the platform_device (if it is available), this breaks the
clock-matching on ARM.
The reason it's there is for instance a case when the shdci device is exposed
from a MFD device which sits on top of PCI. Then the parent (PCI device)
is the device that is DMA capable. This patch will break such usage.
I feared that there is a reason. The problem I see is now, that the parent gets
always set (from drivers/base/platform.c):
Then we obviously need to pass more information in the platform_data to be able
to chose which device to be used.
So, sdhci-plftm cannot access the platform_data connected to the original
platform_device via host->mmc->parent.
You're right it wouldn't. But isn't it a bit risky even if you could access it,
in the long the platform_data coild point to something that is in the __devinit section
or similar?
What about extend the struct you defined with the pieces needed, and access it via
sdhci_priv?
What is the purpose of this patch? You allocate space for an extra struct,
which you have a pointer pointing to, but you never use the pointer?
We want to extend sdhci-pltfm to support the various sdhci-cores on (for now
mainly) ARM platforms. A number of those cores need board specific information
to be used in a custom init()-call, which shall be passed via platform_data.
The pointer will be used in the platform specific extensions.
Sounds good.
Regards,
Richard
Signed-off-by: Wolfram Sang<w.sang@xxxxxxxxxxxxxx>
Cc: Richard Röjfors<richard.rojfors.ext@xxxxxxxxxxxxxxx>
---
Changes since last version:
* added types.h
I saw no types.h?
In the second chunk, the include file.
Thanks,
Wolfram
* removed usage of pdev->dev.parent to ensure clk-matching
Please speak up if this has a use case I failed to see!
drivers/mmc/host/sdhci-pltfm.c | 8 ++++----
drivers/mmc/host/sdhci-pltfm.h | 7 +++++++
2 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/mmc/host/sdhci-pltfm.c b/drivers/mmc/host/sdhci-pltfm.c
index e045e3c..095ca9d 100644
--- a/drivers/mmc/host/sdhci-pltfm.c
+++ b/drivers/mmc/host/sdhci-pltfm.c
@@ -55,6 +55,7 @@ static int __devinit sdhci_pltfm_probe(struct platform_device *pdev)
struct sdhci_pltfm_data *pdata = pdev->dev.platform_data;
const struct platform_device_id *platid = platform_get_device_id(pdev);
struct sdhci_host *host;
+ struct sdhci_pltfm_host *pltfm_host;
struct resource *iomem;
int ret;
@@ -71,16 +72,15 @@ static int __devinit sdhci_pltfm_probe(struct platform_device *pdev)
dev_err(&pdev->dev, "Invalid iomem size. You may "
"experience problems.\n");
- if (pdev->dev.parent)
- host = sdhci_alloc_host(pdev->dev.parent, 0);
- else
- host = sdhci_alloc_host(&pdev->dev, 0);
+ host = sdhci_alloc_host(&pdev->dev, sizeof(*pltfm_host));
if (IS_ERR(host)) {
ret = PTR_ERR(host);
goto err;
}
+ pltfm_host = sdhci_priv(host);
+
host->hw_name = "platform";
if (pdata&& pdata->ops)
host->ops = pdata->ops;
diff --git a/drivers/mmc/host/sdhci-pltfm.h b/drivers/mmc/host/sdhci-pltfm.h
index 900f329..93a0319 100644
--- a/drivers/mmc/host/sdhci-pltfm.h
+++ b/drivers/mmc/host/sdhci-pltfm.h
@@ -11,8 +11,15 @@
#ifndef _DRIVERS_MMC_SDHCI_PLTFM_H
#define _DRIVERS_MMC_SDHCI_PLTFM_H
+#include<linux/clk.h>
+#include<linux/types.h>
#include<linux/sdhci-pltfm.h>
+struct sdhci_pltfm_host {
+ struct clk *clk;
+ u32 scratchpad; /* to handle quirks across io-accessor calls */
+};
+
extern struct sdhci_pltfm_data sdhci_cns3xxx_pdata;
#endif /* _DRIVERS_MMC_SDHCI_PLTFM_H */
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
