Subject: [RFC PATCH 1/3] OMAP: omap_device: Add omap_device_[alloc|delete] for DT integration

From: [email-masked] (Cousson, Benoit)
Date: Fri, 2 Sep 2011 17:22:46 +0200

On 9/1/2011 8:30 PM, Hilman, Kevin wrote:
> Benoit Cousson<[email-masked]>  writes:
> 
>> Split the omap_device_build_ss into two smaller functions
>> that will allow to populate a platform_device already alocated by
>> device-tree.
>> The functionality of the omap_device_build_ss is still the same, but
>> the omap_device_alloc will be usable with devices already built by
>> device-tree.
> 
> Very nice, I started down this path in the original series, but didn't
> finish.
> Some minor comments below...
> 
>> Signed-off-by: Benoit Cousson<[email-masked]>
>> Cc: Kevin Hilman<[email-masked]>
>> ---
>>   arch/arm/plat-omap/omap_device.c |  168 ++++++++++++++++++++++++++------------
>>   1 files changed, 114 insertions(+), 54 deletions(-)
>>
>> diff --git a/arch/arm/plat-omap/omap_device.c b/arch/arm/plat-omap/omap_device.c
>> index f2149be..752d72a 100644
>> --- a/arch/arm/plat-omap/omap_device.c
>> +++ b/arch/arm/plat-omap/omap_device.c
>> @@ -96,6 +96,11 @@
>>
>>   static int omap_device_register(struct platform_device *pdev);
>>   static int omap_early_device_register(struct platform_device *pdev);
>> +static struct omap_device *omap_device_alloc(struct platform_device *pdev,
>> +				      struct omap_hwmod **ohs, int oh_cnt,
>> +				      struct omap_device_pm_latency *pm_lats,
>> +				      int pm_lats_cnt);
>> +
>>
>>   static struct omap_device_pm_latency omap_default_latency[] = {
>>   	{
>> @@ -397,6 +402,105 @@ static int omap_device_fill_resources(struct omap_device *od,
>>   }
>>
>>   /**
>> + * omap_device_alloc - allocate an omap_device
>> + * @pdev: platform_device that will be represent this omap_device
>> + * @oh: ptr to the single omap_hwmod that backs this omap_device
>> + * @pdata: platform_data ptr to associate with the platform_device
>> + * @pdata_len: amount of memory pointed to by @pdata
>> + * @pm_lats: pointer to a omap_device_pm_latency array for this device
>> + * @pm_lats_cnt: ARRAY_SIZE() of @pm_lats
>> + *
>> + * Convenience function for allocating an omap_device structure and filling
>> + * hwmods, resources and pm_latency attributes.
>> + *
>> + * Returns an struct omap_device pointer or ERR_PTR() on error;
>> + */
>> +static struct omap_device *omap_device_alloc(struct platform_device *pdev,
>> +					struct omap_hwmod **ohs, int oh_cnt,
>> +					struct omap_device_pm_latency *pm_lats,
>> +					int pm_lats_cnt)
>> +{
>> +	int ret = -ENOMEM;
>> +	struct omap_device *od;
>> +	struct resource *res = NULL;
>> +	int i, res_count;
>> +	struct omap_hwmod **hwmods;
>> +
>> +	od = kzalloc(sizeof(struct omap_device), GFP_KERNEL);
>> +	if (!od) {
>> +		ret = -ENOMEM;
>> +		goto oda_exit1;
>> +	}
>> +	od->hwmods_cnt = oh_cnt;
>> +
>> +	hwmods = kzalloc(sizeof(struct omap_hwmod *) * oh_cnt,
>> +			 GFP_KERNEL);
>> +	if (!hwmods)
>> +		goto oda_exit2;
>> +
>> +	memcpy(hwmods, ohs, sizeof(struct omap_hwmod *) * oh_cnt);
>> +	od->hwmods = hwmods;
>> +	od->pdev = pdev;
>> +
>> +	if (pdev->num_resources&&  pdev->resource)
>> +		dev_warn(&pdev->dev, "%s(): ressources already allocated %d\n",
> 
> typo: ressources (occurs again below)

It is not a real typo, it is a French word :-)
 
> also, this check/warn should probably go after the 'HACK' comment below.

yep.

> 
>> +			__func__, pdev->num_resources);
>> +	/*
>> +	 * HACK: Idealy the resources from DT should match, and hwmod
> 
> s/Idealy/Ideally/

OK, for that one, I do not have the French word excuse...

> 
>> +	 * should just add the missing ones. Since the name is not
>> +	 * properly populated by DT, stick to hwmod resources only.
> 
> I think this limitation is fine until we come to resolution in the named
> resources debate.

Indeed :-)

>> +	 */
>> +	res_count = omap_device_count_resources(od);
>> +	if (res_count>  0) {
>> +		dev_dbg(&pdev->dev, "%s(): ressources allocated from hwmod %d\n",
>> +			__func__, res_count);
>> +		res = kzalloc(sizeof(struct resource) * res_count, GFP_KERNEL);
>> +		if (!res)
>> +			goto oda_exit3;
>> +
>> +		omap_device_fill_resources(od, res);
>> +
>> +		ret = platform_device_add_resources(pdev, res, res_count);
>> +		kfree(res);
>> +
>> +		if (ret)
>> +			goto oda_exit3;
>> +	}
>> +
>> +	if (pm_lats) {
>> +		od->pm_lats = pm_lats;
>> +		od->pm_lats_cnt = pm_lats_cnt;
>> +	} else {
>> +		od->pm_lats = omap_default_latency;
>> +		od->pm_lats_cnt = ARRAY_SIZE(omap_default_latency);
>> +	}
>> +
>> +	pdev->archdata.od = od;
>> +
>> +	for (i = 0; i<  oh_cnt; i++) {
>> +		hwmods[i]->od = od;
>> +		_add_hwmod_clocks_clkdev(od, hwmods[i]);
>> +	}
>> +
>> +	return od;
>> +
>> +oda_exit3:
>> +	kfree(hwmods);
>> +oda_exit2:
>> +	kfree(od);
>> +oda_exit1:
>> +	dev_err(&pdev->dev, "omap_device: build failed (%d)\n", ret);
>> +
>> +	return ERR_PTR(ret);
>> +}
>> +
>> +void omap_device_delete(struct omap_device *od)
>> +{
>> +	kfree(od->hwmods);
>> +	kfree(od);
> 
> maybe set pdev->archdata.od = NULL too.

OK.

>> +}
>> +
>> +/**
>>    * omap_device_build - build and register an omap_device with one omap_hwmod
>>    * @pdev_name: name of the platform_device driver to use
>>    * @pdev_id: this platform_device's connection ID
>> @@ -455,9 +559,6 @@ struct platform_device *omap_device_build_ss(const char *pdev_name, int pdev_id,
>>   	int ret = -ENOMEM;
>>   	struct platform_device *pdev;
>>   	struct omap_device *od;
>> -	struct resource *res = NULL;
>> -	int i, res_count;
>> -	struct omap_hwmod **hwmods;
>>
>>   	if (!ohs || oh_cnt == 0 || !pdev_name)
>>   		return ERR_PTR(-EINVAL);
>> @@ -471,72 +572,31 @@ struct platform_device *omap_device_build_ss(const char *pdev_name, int pdev_id,
>>   		goto odbs_exit;
>>   	}
>>
>> -	pr_debug("omap_device: %s: building with %d hwmods\n", pdev_name,
>> -		 oh_cnt);
>> +	/* Set the dev_name early to allow dev_xxx in omap_device_alloc */
>> +	if (pdev->id != -1)
>> +		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
>> +	else
>> +		dev_set_name(&pdev->dev, "%s", pdev->name);
> 
> Minor: I think setting dev->init_name is more appropriate here, and
> should have the same effect.

The slight difference is that if I do that:
pdev->dev.init_name = kasprintf(GFP_KERNEL, "%s.%d", pdev->name, pdev->id);

I will have to free it myself, because device_add is doing only that:

        if (dev->init_name) {
                dev_set_name(dev, "%s", dev->init_name);
                dev->init_name = NULL;
        }

Whereas dev_set_name is doing it for me.

So it will add one more line later. Does it worth it?

The init_name seems to be used only to provide a static const name most of the time, hence the lack of kfree.

Thanks for the comments,
Benoit