diff mbox

[v4,3/5] mmc: davinci_mmc: add DT support

Message ID 1360909322-1858-4-git-send-email-prakash.pm@ti.com (mailing list archive)
State New, archived
Headers show

Commit Message

Manjunathappa, Prakash Feb. 15, 2013, 6:22 a.m. UTC 
Adds device tree support for davinci_mmc. Also add binding documentation.
As of now in non-dma PIO mode and without GPIO card_detect/write_protect
option because of dependencies on EDMA and GPIO module DT support.

Signed-off-by: Manjunathappa, Prakash <prakash.pm@ti.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Cc: linux-mmc@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: davinci-linux-open-source@linux.davincidsp.com
Cc: devicetree-discuss@lists.ozlabs.org
Cc: cjb@laptop.org
Cc: Sekhar Nori <nsekhar@ti.com>
Cc: mporter@ti.com
---
Since v2:
Modified the default value for bus-width and removed the support for
highspeed card capabilties for now.
Since v1:
Modified DT parse function to take default values and accomodate controller
version in compatible field.

 .../devicetree/bindings/mmc/davinci_mmc.txt        |   25 ++++++++
 drivers/mmc/host/davinci_mmc.c                     |   66 +++++++++++++++++++-
 2 files changed, 89 insertions(+), 2 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/mmc/davinci_mmc.txt

Comments

Sekhar Nori Feb. 27, 2013, 11:43 a.m. UTC | #1 
On 2/15/2013 11:52 AM, Manjunathappa, Prakash wrote:
> Adds device tree support for davinci_mmc. Also add binding documentation.
> As of now in non-dma PIO mode and without GPIO card_detect/write_protect
> option because of dependencies on EDMA and GPIO module DT support.
> 
> Signed-off-by: Manjunathappa, Prakash <prakash.pm@ti.com>
> Reviewed-by: Mark Rutland <mark.rutland@arm.com>
> Cc: linux-mmc@vger.kernel.org
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: davinci-linux-open-source@linux.davincidsp.com
> Cc: devicetree-discuss@lists.ozlabs.org
> Cc: cjb@laptop.org
> Cc: Sekhar Nori <nsekhar@ti.com>
> Cc: mporter@ti.com

> diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
> index 874dc60..6b08b9a 100644
> --- a/drivers/mmc/host/davinci_mmc.c
> +++ b/drivers/mmc/host/davinci_mmc.c
> @@ -34,6 +34,8 @@
>  #include <linux/dma-mapping.h>
>  #include <linux/edma.h>
>  #include <linux/mmc/mmc.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
>  
>  #include <linux/platform_data/mmc-davinci.h>
>  
> @@ -1156,6 +1158,7 @@ static void __init init_mmcsd_host(struct mmc_davinci_host *host)
>  
>  	mmc_davinci_reset_ctrl(host, 0);
>  }
> +

Stray line addition.

>  static struct platform_device_id davinci_mmc_devtype[] = {
>  	{
>  		.name	= "davinci-mmc-dm355",
> @@ -1168,9 +1171,63 @@ static struct platform_device_id davinci_mmc_devtype[] = {
>  };
>  MODULE_DEVICE_TABLE(platform, davinci_mmc_devtype);
>  
> -static int __init davinci_mmcsd_probe(struct platform_device *pdev)
> +static const struct of_device_id davinci_mmc_dt_ids[] = {
> +	{
> +		.compatible = "ti,davinci-mmc-dm355",
> +		.data = &davinci_mmc_devtype[MMC_CTLR_VERSION_1],
> +	},
> +	{
> +		.compatible = "ti,davinci-mmc-da830",
> +		.data = &davinci_mmc_devtype[MMC_CTLR_VERSION_2],
> +	},
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, davinci_mmc_dt_ids);
> +
> +static struct davinci_mmc_config
> +	*mmc_parse_pdata(struct platform_device *pdev)
>  {
> +	struct device_node *np;
>  	struct davinci_mmc_config *pdata = pdev->dev.platform_data;
> +	const struct of_device_id *match =
> +		of_match_device(of_match_ptr(davinci_mmc_dt_ids), &pdev->dev);
> +	u32 data;
> +
> +	np = pdev->dev.of_node;
> +	if (!np)
> +		return pdata;
> +
> +	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
> +	if (!pdata) {
> +		dev_err(&pdev->dev, "Failed to allocate memory for struct davinci_mmc_config\n");
> +		goto nodata;

devm_kzalloc() returns NULL on error so you will end up returning
success in this case.

> +	}
> +
> +	if (match)
> +		pdev->id_entry = match->data;
> +
> +	of_property_read_u32(np, "max-frequency", &pdata->max_freq);
> +	if (!pdata->max_freq)
> +		dev_info(&pdev->dev, "'max-frequency' property not specified, defaulting to 25MHz\n");


of_property_read_u32() returns error on failure. pdata->max_freq is not
guaranteed to be zero in case of error. See comments atop
of_property_read_u32_array().

> +
> +	of_property_read_u32(np, "bus-width", &data);
> +	switch (data) {
> +	case 1:
> +	case 4:
> +	case 8:
> +		pdata->wires = data;
> +		break;
> +	default:
> +		pdata->wires = 1;
> +		dev_info(&pdev->dev, "Unsupported buswidth, defaulting to 1 bit\n");
> +	}
> +nodata:
> +	return pdata;
> +}
> +

Thanks,
Sekhar
Manjunathappa, Prakash March 5, 2013, 11:24 a.m. UTC | #2 
Hi Sekhar,

On Wed, Feb 27, 2013 at 17:13:43, Nori, Sekhar wrote:
> On 2/15/2013 11:52 AM, Manjunathappa, Prakash wrote:
> > Adds device tree support for davinci_mmc. Also add binding documentation.
> > As of now in non-dma PIO mode and without GPIO card_detect/write_protect
> > option because of dependencies on EDMA and GPIO module DT support.
> > 
> > Signed-off-by: Manjunathappa, Prakash <prakash.pm@ti.com>
> > Reviewed-by: Mark Rutland <mark.rutland@arm.com>
> > Cc: linux-mmc@vger.kernel.org
> > Cc: linux-arm-kernel@lists.infradead.org
> > Cc: davinci-linux-open-source@linux.davincidsp.com
> > Cc: devicetree-discuss@lists.ozlabs.org
> > Cc: cjb@laptop.org
> > Cc: Sekhar Nori <nsekhar@ti.com>
> > Cc: mporter@ti.com
> 
> > diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
> > index 874dc60..6b08b9a 100644
> > --- a/drivers/mmc/host/davinci_mmc.c
> > +++ b/drivers/mmc/host/davinci_mmc.c
> > @@ -34,6 +34,8 @@
> >  #include <linux/dma-mapping.h>
> >  #include <linux/edma.h>
> >  #include <linux/mmc/mmc.h>
> > +#include <linux/of.h>
> > +#include <linux/of_device.h>
> >  
> >  #include <linux/platform_data/mmc-davinci.h>
> >  
> > @@ -1156,6 +1158,7 @@ static void __init init_mmcsd_host(struct mmc_davinci_host *host)
> >  
> >  	mmc_davinci_reset_ctrl(host, 0);
> >  }
> > +
> 
> Stray line addition.
> 

I will fix this.

> >  static struct platform_device_id davinci_mmc_devtype[] = {
> >  	{
> >  		.name	= "davinci-mmc-dm355",
> > @@ -1168,9 +1171,63 @@ static struct platform_device_id davinci_mmc_devtype[] = {
> >  };
> >  MODULE_DEVICE_TABLE(platform, davinci_mmc_devtype);
> >  
> > -static int __init davinci_mmcsd_probe(struct platform_device *pdev)
> > +static const struct of_device_id davinci_mmc_dt_ids[] = {
> > +	{
> > +		.compatible = "ti,davinci-mmc-dm355",
> > +		.data = &davinci_mmc_devtype[MMC_CTLR_VERSION_1],
> > +	},
> > +	{
> > +		.compatible = "ti,davinci-mmc-da830",
> > +		.data = &davinci_mmc_devtype[MMC_CTLR_VERSION_2],
> > +	},
> > +	{},
> > +};
> > +MODULE_DEVICE_TABLE(of, davinci_mmc_dt_ids);
> > +
> > +static struct davinci_mmc_config
> > +	*mmc_parse_pdata(struct platform_device *pdev)
> >  {
> > +	struct device_node *np;
> >  	struct davinci_mmc_config *pdata = pdev->dev.platform_data;
> > +	const struct of_device_id *match =
> > +		of_match_device(of_match_ptr(davinci_mmc_dt_ids), &pdev->dev);
> > +	u32 data;
> > +
> > +	np = pdev->dev.of_node;
> > +	if (!np)
> > +		return pdata;
> > +
> > +	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
> > +	if (!pdata) {
> > +		dev_err(&pdev->dev, "Failed to allocate memory for struct davinci_mmc_config\n");
> > +		goto nodata;
> 
> devm_kzalloc() returns NULL on error so you will end up returning
> success in this case.
> 

Returns NULL on failure, caller is checking on NULL for failures.

        pdata = mmc_parse_pdata(pdev);
        if (pdata == NULL) {
                dev_err(&pdev->dev, "Can not get platform data\n");
                return -ENOENT;
        }

> > +	}
> > +
> > +	if (match)
> > +		pdev->id_entry = match->data;
> > +
> > +	of_property_read_u32(np, "max-frequency", &pdata->max_freq);
> > +	if (!pdata->max_freq)
> > +		dev_info(&pdev->dev, "'max-frequency' property not specified, defaulting to 25MHz\n");
> 
> 
> of_property_read_u32() returns error on failure. pdata->max_freq is not
> guaranteed to be zero in case of error. See comments atop
> of_property_read_u32_array().
> 

As pdata is from kzalloc, max_freq will remain NULL in case of_property_read_u32_array fails.
It makes sense to check for return value, I agree to change this.

Thanks,
Prakash
Sekhar Nori March 5, 2013, 11:46 a.m. UTC | #3 
On 3/5/2013 4:54 PM, Manjunathappa, Prakash wrote:

>>> +	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
>>> +	if (!pdata) {
>>> +		dev_err(&pdev->dev, "Failed to allocate memory for struct davinci_mmc_config\n");
>>> +		goto nodata;
>>
>> devm_kzalloc() returns NULL on error so you will end up returning
>> success in this case.
>>
> 
> Returns NULL on failure, caller is checking on NULL for failures.
> 
>         pdata = mmc_parse_pdata(pdev);
>         if (pdata == NULL) {
>                 dev_err(&pdev->dev, "Can not get platform data\n");
>                 return -ENOENT;
>         }

Ha, okay. I was somehow confused into thinking this is part of probe
routine.

Thanks,
Sekhar
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/mmc/davinci_mmc.txt b/Documentation/devicetree/bindings/mmc/davinci_mmc.txt
new file mode 100644
index 0000000..247be0f
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/davinci_mmc.txt
@@ -0,0 +1,25 @@ 
+* TI Highspeed MMC host controller for DaVinci
+
+The Highspeed MMC Host Controller on TI DaVinci family
+provides an interface for MMC, SD and SDIO types of memory cards.
+
+This file documents the properties used by the davinci_mmc driver.
+
+Required properties:
+- compatible:
+ Should be "ti,davinci-mmc-da830": for da830, da850, dm365
+ Should be "ti,davinci-mmc-dm355": for dm355, dm644x
+
+Optional properties:
+- bus-width: Number of data lines, can be <1>, <4>, or <8>, default <1>
+- max-frequency: Maximum operating clock frequency, default 25MHz.
+
+Example:
+	mmc0: mmc@1c40000 {
+		compatible = "ti,davinci-mmc-da830",
+		reg = <0x40000 0x1000>;
+		interrupts = <16>;
+		status = "okay";
+		bus-width = <4>;
+		max-frequency = <50000000>;
+	};
diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
index 874dc60..6b08b9a 100644
--- a/drivers/mmc/host/davinci_mmc.c
+++ b/drivers/mmc/host/davinci_mmc.c
@@ -34,6 +34,8 @@ 
 #include <linux/dma-mapping.h>
 #include <linux/edma.h>
 #include <linux/mmc/mmc.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
 
 #include <linux/platform_data/mmc-davinci.h>
 
@@ -1156,6 +1158,7 @@  static void __init init_mmcsd_host(struct mmc_davinci_host *host)
 
 	mmc_davinci_reset_ctrl(host, 0);
 }
+
 static struct platform_device_id davinci_mmc_devtype[] = {
 	{
 		.name	= "davinci-mmc-dm355",
@@ -1168,9 +1171,63 @@  static struct platform_device_id davinci_mmc_devtype[] = {
 };
 MODULE_DEVICE_TABLE(platform, davinci_mmc_devtype);
 
-static int __init davinci_mmcsd_probe(struct platform_device *pdev)
+static const struct of_device_id davinci_mmc_dt_ids[] = {
+	{
+		.compatible = "ti,davinci-mmc-dm355",
+		.data = &davinci_mmc_devtype[MMC_CTLR_VERSION_1],
+	},
+	{
+		.compatible = "ti,davinci-mmc-da830",
+		.data = &davinci_mmc_devtype[MMC_CTLR_VERSION_2],
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, davinci_mmc_dt_ids);
+
+static struct davinci_mmc_config
+	*mmc_parse_pdata(struct platform_device *pdev)
 {
+	struct device_node *np;
 	struct davinci_mmc_config *pdata = pdev->dev.platform_data;
+	const struct of_device_id *match =
+		of_match_device(of_match_ptr(davinci_mmc_dt_ids), &pdev->dev);
+	u32 data;
+
+	np = pdev->dev.of_node;
+	if (!np)
+		return pdata;
+
+	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata) {
+		dev_err(&pdev->dev, "Failed to allocate memory for struct davinci_mmc_config\n");
+		goto nodata;
+	}
+
+	if (match)
+		pdev->id_entry = match->data;
+
+	of_property_read_u32(np, "max-frequency", &pdata->max_freq);
+	if (!pdata->max_freq)
+		dev_info(&pdev->dev, "'max-frequency' property not specified, defaulting to 25MHz\n");
+
+	of_property_read_u32(np, "bus-width", &data);
+	switch (data) {
+	case 1:
+	case 4:
+	case 8:
+		pdata->wires = data;
+		break;
+	default:
+		pdata->wires = 1;
+		dev_info(&pdev->dev, "Unsupported buswidth, defaulting to 1 bit\n");
+	}
+nodata:
+	return pdata;
+}
+
+static int __init davinci_mmcsd_probe(struct platform_device *pdev)
+{
+	struct davinci_mmc_config *pdata = NULL;
 	struct mmc_davinci_host *host = NULL;
 	struct mmc_host *mmc = NULL;
 	struct resource *r, *mem = NULL;
@@ -1178,7 +1235,11 @@  static int __init davinci_mmcsd_probe(struct platform_device *pdev)
 	size_t mem_size;
 	const struct platform_device_id *id_entry;
 
-	/* REVISIT:  when we're fully converted, fail if pdata is NULL */
+	pdata = mmc_parse_pdata(pdev);
+	if (pdata == NULL) {
+		dev_err(&pdev->dev, "Can not get platform data\n");
+		return -ENOENT;
+	}
 
 	ret = -ENODEV;
 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -1422,6 +1483,7 @@  static struct platform_driver davinci_mmcsd_driver = {
 		.name	= "davinci_mmc",
 		.owner	= THIS_MODULE,
 		.pm	= davinci_mmcsd_pm_ops,
+		.of_match_table = of_match_ptr(davinci_mmc_dt_ids),
 	},
 	.remove		= __exit_p(davinci_mmcsd_remove),
 	.id_table	= davinci_mmc_devtype,