[alsa-devel] [PATCH 1/5] ALSA: dice: split subaddress check from category check

Takashi Sakamoto o-takashi at sakamocchi.jp
Tue Dec 29 10:33:07 CET 2015


On 2015年12月29日 17:54, Takashi Iwai wrote:
> On Sat, 26 Dec 2015 04:35:22 +0100,
> Takashi Sakamoto wrote:
>>
>> Before allocating an instance of sound card, ALSA dice driver checks
>> chip_ID_hi in Bus information block of Config ROM, then also checks
>> subaddresses. The former operation reads cache of Config ROM in Linux
>> FireWire subsystem, while the latter operation sends read transaction.
>> The latter can be merged into initialization of transaction system.
>>
>> This commit splits these two operations to reduce needless transactions
>> in probe processing.
>>
>> Signed-off-by: Takashi Sakamoto <o-takashi at sakamocchi.jp>
>> ---
>>  sound/firewire/dice/dice-transaction.c | 89 ++++++++++++++++++++++++++--------
>>  sound/firewire/dice/dice.c             | 72 +++------------------------
>>  2 files changed, 77 insertions(+), 84 deletions(-)
>>
>> diff --git a/sound/firewire/dice/dice-transaction.c b/sound/firewire/dice/dice-transaction.c
>> index aee7461..75a2125 100644
>> --- a/sound/firewire/dice/dice-transaction.c
>> +++ b/sound/firewire/dice/dice-transaction.c
>> @@ -331,39 +331,59 @@ int snd_dice_transaction_reinit(struct snd_dice *dice)
>>  	return register_notification_address(dice, false);
>>  }
>>  
>> -int snd_dice_transaction_init(struct snd_dice *dice)
>> +static int get_subaddrs(struct snd_dice *dice)
>>  {
>> -	struct fw_address_handler *handler = &dice->notification_handler;
>> +	static const int min_values[10] = {
>> +		10, 0x64 / 4,
>> +		10, 0x18 / 4,
>> +		10, 0x18 / 4,
>> +		0, 0,
>> +		0, 0,
>> +	};
>>  	__be32 *pointers;
>> +	u32 data;
>> +	unsigned int i;
>>  	int err;
>>  
>> -	/* Use the same way which dice_interface_check() does. */
>> -	pointers = kmalloc(sizeof(__be32) * 10, GFP_KERNEL);
>> +	pointers = kmalloc_array(ARRAY_SIZE(min_values), sizeof(__be32),
>> +				 GFP_KERNEL);
>>  	if (pointers == NULL)
>>  		return -ENOMEM;
>>  
>> -	/* Get offsets for sub-addresses */
>> +	/*
>> +	 * Check that the sub address spaces exist and are located inside the
>> +	 * private address space.  The minimum values are chosen so that all
>> +	 * minimally required registers are included.
>> +	 */
>>  	err = snd_fw_transaction(dice->unit, TCODE_READ_BLOCK_REQUEST,
>> -				 DICE_PRIVATE_SPACE,
>> -				 pointers, sizeof(__be32) * 10, 0);
>> +				 DICE_PRIVATE_SPACE, pointers,
>> +				 sizeof(__be32) * ARRAY_SIZE(min_values), 0);
>>  	if (err < 0)
>>  		goto end;
>>  
>> -	/* Allocation callback in address space over host controller */
>> -	handler->length = 4;
>> -	handler->address_callback = dice_notification;
>> -	handler->callback_data = dice;
>> -	err = fw_core_add_address_handler(handler, &fw_high_memory_region);
>> -	if (err < 0) {
>> -		handler->callback_data = NULL;
>> -		goto end;
>> +	for (i = 0; i < ARRAY_SIZE(min_values); ++i) {
>> +		data = be32_to_cpu(pointers[i]);
>> +		if (data < min_values[i] || data >= 0x40000) {
>> +			err = -ENODEV;
>> +			goto end;
>> +		}
>>  	}
>>  
>> -	/* Register the address space */
>> -	err = register_notification_address(dice, true);
>> -	if (err < 0) {
>> -		fw_core_remove_address_handler(handler);
>> -		handler->callback_data = NULL;
>> +	/*
>> +	 * Check that the implemented DICE driver specification major version
>> +	 * number matches.
>> +	 */
>> +	err = snd_fw_transaction(dice->unit, TCODE_READ_QUADLET_REQUEST,
>> +				 DICE_PRIVATE_SPACE +
>> +				 be32_to_cpu(pointers[0]) * 4 + GLOBAL_VERSION,
>> +				 &data, sizeof(data), 0);
> 
> It's confusing to reuse a single variable as both u32 and be32.
> Use the specific variable like the original code instead.

OK.

> thanks,
> 
> Takashi
> 
> 
>> +	if (err < 0)
>> +		goto end;
>> +
>> +	if ((data & cpu_to_be32(0xff000000)) != cpu_to_be32(0x01000000)) {
>> +		dev_err(&dice->unit->device,
>> +			"unknown DICE version: 0x%08x\n", be32_to_cpu(data));
>> +		err = -ENODEV;
>>  		goto end;
>>  	}
>>  
>> @@ -380,3 +400,32 @@ end:
>>  	kfree(pointers);
>>  	return err;
>>  }
>> +
>> +int snd_dice_transaction_init(struct snd_dice *dice)
>> +{
>> +	struct fw_address_handler *handler = &dice->notification_handler;
>> +	int err;
>> +
>> +	err = get_subaddrs(dice);
>> +	if (err < 0)
>> +		return err;
>> +
>> +	/* Allocation callback in address space over host controller */
>> +	handler->length = 4;
>> +	handler->address_callback = dice_notification;
>> +	handler->callback_data = dice;
>> +	err = fw_core_add_address_handler(handler, &fw_high_memory_region);
>> +	if (err < 0) {
>> +		handler->callback_data = NULL;
>> +		return err;
>> +	}
>> +
>> +	/* Register the address space */
>> +	err = register_notification_address(dice, true);
>> +	if (err < 0) {
>> +		fw_core_remove_address_handler(handler);
>> +		handler->callback_data = NULL;
>> +	}
>> +
>> +	return err;
>> +}
>> diff --git a/sound/firewire/dice/dice.c b/sound/firewire/dice/dice.c
>> index 0cda05c..26271cc 100644
>> --- a/sound/firewire/dice/dice.c
>> +++ b/sound/firewire/dice/dice.c
>> @@ -18,27 +18,12 @@ MODULE_LICENSE("GPL v2");
>>  #define WEISS_CATEGORY_ID	0x00
>>  #define LOUD_CATEGORY_ID	0x10
>>  
>> -static int dice_interface_check(struct fw_unit *unit)
>> +static int check_dice_category(struct fw_unit *unit)
>>  {
>> -	static const int min_values[10] = {
>> -		10, 0x64 / 4,
>> -		10, 0x18 / 4,
>> -		10, 0x18 / 4,
>> -		0, 0,
>> -		0, 0,
>> -	};
>>  	struct fw_device *device = fw_parent_device(unit);
>>  	struct fw_csr_iterator it;
>> -	int key, val, vendor = -1, model = -1, err;
>> -	unsigned int category, i;
>> -	__be32 *pointers;
>> -	u32 value;
>> -	__be32 version;
>> -
>> -	pointers = kmalloc_array(ARRAY_SIZE(min_values), sizeof(__be32),
>> -				 GFP_KERNEL);
>> -	if (pointers == NULL)
>> -		return -ENOMEM;
>> +	int key, val, vendor = -1, model = -1;
>> +	unsigned int category;
>>  
>>  	/*
>>  	 * Check that GUID and unit directory are constructed according to DICE
>> @@ -64,51 +49,10 @@ static int dice_interface_check(struct fw_unit *unit)
>>  	else
>>  		category = DICE_CATEGORY_ID;
>>  	if (device->config_rom[3] != ((vendor << 8) | category) ||
>> -	    device->config_rom[4] >> 22 != model) {
>> -		err = -ENODEV;
>> -		goto end;
>> -	}
>> -
>> -	/*
>> -	 * Check that the sub address spaces exist and are located inside the
>> -	 * private address space.  The minimum values are chosen so that all
>> -	 * minimally required registers are included.
>> -	 */
>> -	err = snd_fw_transaction(unit, TCODE_READ_BLOCK_REQUEST,
>> -				 DICE_PRIVATE_SPACE, pointers,
>> -				 sizeof(__be32) * ARRAY_SIZE(min_values), 0);
>> -	if (err < 0) {
>> -		err = -ENODEV;
>> -		goto end;
>> -	}
>> -	for (i = 0; i < ARRAY_SIZE(min_values); ++i) {
>> -		value = be32_to_cpu(pointers[i]);
>> -		if (value < min_values[i] || value >= 0x40000) {
>> -			err = -ENODEV;
>> -			goto end;
>> -		}
>> -	}
>> +	    device->config_rom[4] >> 22 != model)
>> +		return -ENODEV;
>>  
>> -	/*
>> -	 * Check that the implemented DICE driver specification major version
>> -	 * number matches.
>> -	 */
>> -	err = snd_fw_transaction(unit, TCODE_READ_QUADLET_REQUEST,
>> -				 DICE_PRIVATE_SPACE +
>> -				 be32_to_cpu(pointers[0]) * 4 + GLOBAL_VERSION,
>> -				 &version, 4, 0);
>> -	if (err < 0) {
>> -		err = -ENODEV;
>> -		goto end;
>> -	}
>> -	if ((version & cpu_to_be32(0xff000000)) != cpu_to_be32(0x01000000)) {
>> -		dev_err(&unit->device,
>> -			"unknown DICE version: 0x%08x\n", be32_to_cpu(version));
>> -		err = -ENODEV;
>> -		goto end;
>> -	}
>> -end:
>> -	return err;
>> +	return 0;
>>  }
>>  
>>  static int highest_supported_mode_rate(struct snd_dice *dice,
>> @@ -254,9 +198,9 @@ static int dice_probe(struct fw_unit *unit, const struct ieee1394_device_id *id)
>>  	struct snd_dice *dice;
>>  	int err;
>>  
>> -	err = dice_interface_check(unit);
>> +	err = check_dice_category(unit);
>>  	if (err < 0)
>> -		goto end;
>> +		return -ENODEV;
>>  
>>  	err = snd_card_new(&unit->device, -1, NULL, THIS_MODULE,
>>  			   sizeof(*dice), &card);
>> -- 
>> 2.5.0



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