/**
* eeprom_93cx6_read - Read multiple words from eeprom
* @eeprom: Pointer to eeprom structure
* @word: Word index from where we should start reading
* @data: target pointer where the information will have to be stored
*
* This function will read the eeprom data as host-endian word
* into the given data pointer.
*/
void eeprom_93cx6_read(struct eeprom_93cx6 *eeprom, const u8 word,
u16 *data)
{
u16 command;
/*
* Initialize the eeprom register
*/
eeprom_93cx6_startup(eeprom);
/*
* Select the read opcode and the word to be read.
*/
command = (PCI_EEPROM_READ_OPCODE << eeprom->width) | word;
eeprom_93cx6_write_bits(eeprom, command,
PCI_EEPROM_WIDTH_OPCODE + eeprom->width);
/*
* Read the requested 16 bits.
*/
eeprom_93cx6_read_bits(eeprom, data, 16);
/*
* Cleanup eeprom register.
*/
eeprom_93cx6_cleanup(eeprom);
}
/**
* eeprom_93cx6_write - write data to the EEPROM
* @eeprom: Pointer to eeprom structure
* @addr: Address to write data to.
* @data: The data to write to address @addr.
*
* Write the @data to the specified @addr in the EEPROM and
* waiting for the device to finish writing.
*
* Note, since we do not expect large number of write operations
* we delay in between parts of the operation to avoid using excessive
* amounts of CPU time busy waiting.
*/
void eeprom_93cx6_write(struct eeprom_93cx6 *eeprom, u8 addr, u16 data)
{
int timeout = 100;
u16 command;
/* start the command */
eeprom_93cx6_startup(eeprom);
command = PCI_EEPROM_WRITE_OPCODE << eeprom->width;
command |= addr;
/* send write command */
eeprom_93cx6_write_bits(eeprom, command,
PCI_EEPROM_WIDTH_OPCODE + eeprom->width);
/* send data */
eeprom_93cx6_write_bits(eeprom, data, 16);
/* get ready to check for busy */
eeprom->drive_data = 0;
eeprom->reg_chip_select = 1;
eeprom->register_write(eeprom);
/* wait at-least 250ns to get DO to be the busy signal */
usleep_range(1000, 2000);
/* wait for DO to go high to signify finish */
while (true) {
eeprom->register_read(eeprom);
if (eeprom->reg_data_out)
break;
usleep_range(1000, 2000);
if (--timeout <= 0) {
printk(KERN_ERR "%s: timeout\n", __func__);
break;
}
}
eeprom_93cx6_cleanup(eeprom);
}
void eeprom_93cx6_write(struct eeprom_93cx6 *eeprom, u8 addr, u16 data)
{
int timeout = 100;
u16 command;
eeprom_93cx6_startup(eeprom);
command = PCI_EEPROM_WRITE_OPCODE << eeprom->width;
command |= addr;
eeprom_93cx6_write_bits(eeprom, command,
PCI_EEPROM_WIDTH_OPCODE + eeprom->width);
eeprom_93cx6_write_bits(eeprom, data, 16);
eeprom->drive_data = 0;
eeprom->reg_chip_select = 1;
eeprom->register_write(eeprom);
usleep_range(1000, 2000);
while (true) {
eeprom->register_read(eeprom);
if (eeprom->reg_data_out)
break;
usleep_range(1000, 2000);
if (--timeout <= 0) {
printk(KERN_ERR "%s: timeout\n", __func__);
break;
}
}
eeprom_93cx6_cleanup(eeprom);
}
void eeprom_93cx6_read(struct eeprom_93cx6 *eeprom, const u8 word,
u16 *data)
{
u16 command;
eeprom_93cx6_startup(eeprom);
command = (PCI_EEPROM_READ_OPCODE << eeprom->width) | word;
eeprom_93cx6_write_bits(eeprom, command,
PCI_EEPROM_WIDTH_OPCODE + eeprom->width);
eeprom_93cx6_read_bits(eeprom, data, 16);
eeprom_93cx6_cleanup(eeprom);
}
/**
* eeprom_93cx6_wren - set the write enable state
* @eeprom: Pointer to eeprom structure
* @enable: true to enable writes, otherwise disable writes
*
* Set the EEPROM write enable state to either allow or deny
* writes depending on the @enable value.
*/
void eeprom_93cx6_wren(struct eeprom_93cx6 *eeprom, bool enable)
{
u16 command;
/* start the command */
eeprom_93cx6_startup(eeprom);
/* create command to enable/disable */
command = enable ? PCI_EEPROM_EWEN_OPCODE : PCI_EEPROM_EWDS_OPCODE;
command <<= (eeprom->width - 2);
eeprom_93cx6_write_bits(eeprom, command,
PCI_EEPROM_WIDTH_OPCODE + eeprom->width);
eeprom_93cx6_cleanup(eeprom);
}
