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Generalise three-wire interface to generic SPI interface.

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Update rtl8139 driver to instantiate an SPI interface with a three-wire
device attached.
This commit is contained in:
Michael Brown
2006-06-14 00:22:50 +00:00
parent ab4f96e525
commit 3b51c719d3
6 changed files with 427 additions and 182 deletions
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49
src/drivers/nvs/threewire.c
View File

@@ -16,53 +16,42 @@
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <timer.h>
#include <gpxe/nvs/threewire.h>
#include <stddef.h>
#include <byteswap.h>
#include <gpxe/spi.h>
#include <gpxe/threewire.h>
/** @file
*
* Three-wire serial interface
* Three-wire serial devices
*
*/
/**
* Read from a three-wire device
*
* @v three Three-wire interface
* @v three Three-wire device
* @v address Address
* @ret data Data
*/
unsigned long threewire_read ( struct threewire *three,
unsigned long threewire_read ( struct threewire_device *three,
unsigned long address ) {
struct threewire_operations *ops = three->ops;
unsigned long command;
unsigned long data;
int i;
struct spi_interface *spi = three->spi;
uint32_t data;
/* Activate chip select line */
spi->select_slave ( spi, three->slave );
ops->setcs ( three, 1 );
/* Send command and address */
command = threewire_cmd_read ( three, address );
for ( i = ( threewire_cmd_len ( three ) - 1 ) ; i >= 0 ; i-- ) {
ops->setdi ( three, ( command >> i ) & 0x1 );
udelay ( three->udelay );
ops->setsk ( three, 1 );
udelay ( three->udelay );
ops->setsk ( three, 0 );
}
data = cpu_to_le32 ( threewire_cmd_read ( three, address ) );
spi->transfer ( spi, &data, NULL, threewire_cmd_len ( three ) );
/* Read back data */
data = 0;
for ( i = three->datasize ; i ; i-- ) {
udelay ( three->udelay );
ops->setsk ( three, 1 );
udelay ( three->udelay );
data <<= 1;
data |= ops->getdo ( three );
ops->setsk ( three, 0 );
}
spi->transfer ( spi, NULL, &data, three->datasize );
ops->setcs ( three, 0 );
/* Deactivate chip select line */
spi->deselect_slave ( spi );
return data;
return le32_to_cpu ( data );;
}