diff options
| -rw-r--r-- | drivers/misc/eeprom/eeprom_93cx6.c | 85 | ||||
| -rw-r--r-- | include/linux/eeprom_93cx6.h | 6 |
2 files changed, 91 insertions, 0 deletions
diff --git a/drivers/misc/eeprom/eeprom_93cx6.c b/drivers/misc/eeprom/eeprom_93cx6.c index a6037af6f076..0ff4b02177be 100644 --- a/drivers/misc/eeprom/eeprom_93cx6.c +++ b/drivers/misc/eeprom/eeprom_93cx6.c @@ -234,3 +234,88 @@ void eeprom_93cx6_multiread(struct eeprom_93cx6 *eeprom, const u8 word, } EXPORT_SYMBOL_GPL(eeprom_93cx6_multiread); +/** + * 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); +} +EXPORT_SYMBOL_GPL(eeprom_93cx6_wren); + +/** + * 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); +} +EXPORT_SYMBOL_GPL(eeprom_93cx6_write); diff --git a/include/linux/eeprom_93cx6.h b/include/linux/eeprom_93cx6.h index e04546e9c592..e50f98b0297a 100644 --- a/include/linux/eeprom_93cx6.h +++ b/include/linux/eeprom_93cx6.h @@ -33,6 +33,7 @@ #define PCI_EEPROM_WIDTH_93C86 8 #define PCI_EEPROM_WIDTH_OPCODE 3 #define PCI_EEPROM_WRITE_OPCODE 0x05 +#define PCI_EEPROM_ERASE_OPCODE 0x07 #define PCI_EEPROM_READ_OPCODE 0x06 #define PCI_EEPROM_EWDS_OPCODE 0x10 #define PCI_EEPROM_EWEN_OPCODE 0x13 @@ -74,3 +75,8 @@ extern void eeprom_93cx6_read(struct eeprom_93cx6 *eeprom, const u8 word, u16 *data); extern void eeprom_93cx6_multiread(struct eeprom_93cx6 *eeprom, const u8 word, __le16 *data, const u16 words); + +extern void eeprom_93cx6_wren(struct eeprom_93cx6 *eeprom, bool enable); + +extern void eeprom_93cx6_write(struct eeprom_93cx6 *eeprom, + u8 addr, u16 data); |