[U-Boot] [PATCH] dm: spi: Read default speed, mode values from DT

[Vignesh R]

On 04/09/2016 01:15 AM, Tom Rini wrote:
> On Thu, Apr 07, 2016 at 09:02:26PM +0530, Vignesh R wrote:
> 
>> In case of DT boot, don't read default speed and mode for SPI from
>> CONFIG_*, instead read from DT node. This will make sure that boards
>> with multiple SPI/QSPI controllers can be probed at different
>> bus frequencies and modes.
>>
>> Signed-off-by: Vignesh R <vigneshr at ti.com>
>> ---
>>  cmd/sf.c                 | 2 ++
>>  drivers/spi/spi-uclass.c | 8 ++++++--
>>  2 files changed, 8 insertions(+), 2 deletions(-)
>>
>> diff --git a/cmd/sf.c b/cmd/sf.c
>> index 42862d9d921a..4c40d5104422 100644
>> --- a/cmd/sf.c
>> +++ b/cmd/sf.c
>> @@ -88,6 +88,8 @@ static int do_spi_flash_probe(int argc, char * const argv[])
>>  #ifdef CONFIG_DM_SPI_FLASH
>>  	struct udevice *new, *bus_dev;
>>  	int ret;
>> +	/* In DM mode defaults wiil be taken from DT */
>> +	speed = -1, mode = -1;
>>  #else
>>  	struct spi_flash *new;
>>  #endif
>> diff --git a/drivers/spi/spi-uclass.c b/drivers/spi/spi-uclass.c
>> index 5561f36762f9..55ebb5ef19b7 100644
>> --- a/drivers/spi/spi-uclass.c
>> +++ b/drivers/spi/spi-uclass.c
>> @@ -264,6 +264,7 @@ int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
>>  		       struct udevice **busp, struct spi_slave **devp)
>>  {
>>  	struct udevice *bus, *dev;
>> +	struct dm_spi_slave_platdata *plat;
>>  	bool created = false;
>>  	int ret;
>>  
>> @@ -280,8 +281,6 @@ int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
>>  	 * SPI flash chip - we will bind to the correct driver.
>>  	 */
>>  	if (ret == -ENODEV && drv_name) {
>> -		struct dm_spi_slave_platdata *plat;
>> -
>>  		debug("%s: Binding new device '%s', busnum=%d, cs=%d, driver=%s\n",
>>  		      __func__, dev_name, busnum, cs, drv_name);
>>  		ret = device_bind_driver(bus, drv_name, dev_name, &dev);
>> @@ -308,6 +307,11 @@ int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
>>  		slave->dev = dev;
>>  	}
>>  
>> +	plat = dev_get_parent_platdata(dev);
>> +	if (speed == -1)
>> +		speed = plat->max_hz;
>> +	if (mode == -1)
>> +		mode = plat->mode;
>>  	ret = spi_set_speed_mode(bus, speed, mode);
>>  	if (ret)
>>  		goto err;
> 
> I like the concept but if it can fail, passing -1 for speed/mode seems
> like a bad idea and we should just fail.
> 
I didn't quite understand your comment. Could you explain what can fail?
I don't think mode/speed will be -1 when calling spi_set_speed_mode()
after above change. speed/mode will either be command line arg passed to
sf probe cmd or CONFIG_SF_DEFAULT_* in case of non DM driver or
mode/speed specified in DT node in case of DM.



-- 
Regards
Vignesh