diff options
author | Sebastien Jan <s-jan@ti.com> | 2010-05-05 08:45:53 +0000 |
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committer | David S. Miller <davem@davemloft.net> | 2010-05-05 21:27:44 -0700 |
commit | a4bdfff74464f86d7e3b8feaf42d18960adc5514 (patch) | |
tree | 4dcde38694ca796b1a3d04a0044948397b497f6c /drivers/net/ks8851.c | |
parent | 7d9974666e0dc2cbbeac80fa4d550df0bbea6fad (diff) | |
download | linux-a4bdfff74464f86d7e3b8feaf42d18960adc5514.tar.bz2 |
ks8851: Low level functions for read/write to companion eeprom
Low-level functions provide 16bits words read and write capability
to ks8851 companion eeprom.
Signed-off-by: Sebastien Jan <s-jan@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ks8851.c')
-rw-r--r-- | drivers/net/ks8851.c | 228 |
1 files changed, 228 insertions, 0 deletions
diff --git a/drivers/net/ks8851.c b/drivers/net/ks8851.c index 623171f37d99..3dba57b72ef8 100644 --- a/drivers/net/ks8851.c +++ b/drivers/net/ks8851.c @@ -1034,6 +1034,234 @@ static const struct net_device_ops ks8851_netdev_ops = { .ndo_validate_addr = eth_validate_addr, }; +/* Companion eeprom access */ + +enum { /* EEPROM programming states */ + EEPROM_CONTROL, + EEPROM_ADDRESS, + EEPROM_DATA, + EEPROM_COMPLETE +}; + +/** + * ks8851_eeprom_read - read a 16bits word in ks8851 companion EEPROM + * @dev: The network device the PHY is on. + * @addr: EEPROM address to read + * + * eeprom_size: used to define the data coding length. Can be changed + * through debug-fs. + * + * Programs a read on the EEPROM using ks8851 EEPROM SW access feature. + * Warning: The READ feature is not supported on ks8851 revision 0. + * + * Rough programming model: + * - on period start: set clock high and read value on bus + * - on period / 2: set clock low and program value on bus + * - start on period / 2 + */ +unsigned int ks8851_eeprom_read(struct net_device *dev, unsigned int addr) +{ + struct ks8851_net *ks = netdev_priv(dev); + int eepcr; + int ctrl = EEPROM_OP_READ; + int state = EEPROM_CONTROL; + int bit_count = EEPROM_OP_LEN - 1; + unsigned int data = 0; + int dummy; + unsigned int addr_len; + + addr_len = (ks->eeprom_size == 128) ? 6 : 8; + + /* start transaction: chip select high, authorize write */ + mutex_lock(&ks->lock); + eepcr = EEPCR_EESA | EEPCR_EESRWA; + ks8851_wrreg16(ks, KS_EEPCR, eepcr); + eepcr |= EEPCR_EECS; + ks8851_wrreg16(ks, KS_EEPCR, eepcr); + mutex_unlock(&ks->lock); + + while (state != EEPROM_COMPLETE) { + /* falling clock period starts... */ + /* set EED_IO pin for control and address */ + eepcr &= ~EEPCR_EEDO; + switch (state) { + case EEPROM_CONTROL: + eepcr |= ((ctrl >> bit_count) & 1) << 2; + if (bit_count-- <= 0) { + bit_count = addr_len - 1; + state = EEPROM_ADDRESS; + } + break; + case EEPROM_ADDRESS: + eepcr |= ((addr >> bit_count) & 1) << 2; + bit_count--; + break; + case EEPROM_DATA: + /* Change to receive mode */ + eepcr &= ~EEPCR_EESRWA; + break; + } + + /* lower clock */ + eepcr &= ~EEPCR_EESCK; + + mutex_lock(&ks->lock); + ks8851_wrreg16(ks, KS_EEPCR, eepcr); + mutex_unlock(&ks->lock); + + /* waitread period / 2 */ + udelay(EEPROM_SK_PERIOD / 2); + + /* rising clock period starts... */ + + /* raise clock */ + mutex_lock(&ks->lock); + eepcr |= EEPCR_EESCK; + ks8851_wrreg16(ks, KS_EEPCR, eepcr); + mutex_unlock(&ks->lock); + + /* Manage read */ + switch (state) { + case EEPROM_ADDRESS: + if (bit_count < 0) { + bit_count = EEPROM_DATA_LEN - 1; + state = EEPROM_DATA; + } + break; + case EEPROM_DATA: + mutex_lock(&ks->lock); + dummy = ks8851_rdreg16(ks, KS_EEPCR); + mutex_unlock(&ks->lock); + data |= ((dummy >> EEPCR_EESB_OFFSET) & 1) << bit_count; + if (bit_count-- <= 0) + state = EEPROM_COMPLETE; + break; + } + + /* wait period / 2 */ + udelay(EEPROM_SK_PERIOD / 2); + } + + /* close transaction */ + mutex_lock(&ks->lock); + eepcr &= ~EEPCR_EECS; + ks8851_wrreg16(ks, KS_EEPCR, eepcr); + eepcr = 0; + ks8851_wrreg16(ks, KS_EEPCR, eepcr); + mutex_unlock(&ks->lock); + + return data; +} + +/** + * ks8851_eeprom_write - write a 16bits word in ks8851 companion EEPROM + * @dev: The network device the PHY is on. + * @op: operand (can be WRITE, EWEN, EWDS) + * @addr: EEPROM address to write + * @data: data to write + * + * eeprom_size: used to define the data coding length. Can be changed + * through debug-fs. + * + * Programs a write on the EEPROM using ks8851 EEPROM SW access feature. + * + * Note that a write enable is required before writing data. + * + * Rough programming model: + * - on period start: set clock high + * - on period / 2: set clock low and program value on bus + * - start on period / 2 + */ +void ks8851_eeprom_write(struct net_device *dev, unsigned int op, + unsigned int addr, unsigned int data) +{ + struct ks8851_net *ks = netdev_priv(dev); + int eepcr; + int state = EEPROM_CONTROL; + int bit_count = EEPROM_OP_LEN - 1; + unsigned int addr_len; + + addr_len = (ks->eeprom_size == 128) ? 6 : 8; + + switch (op) { + case EEPROM_OP_EWEN: + addr = 0x30; + break; + case EEPROM_OP_EWDS: + addr = 0; + break; + } + + /* start transaction: chip select high, authorize write */ + mutex_lock(&ks->lock); + eepcr = EEPCR_EESA | EEPCR_EESRWA; + ks8851_wrreg16(ks, KS_EEPCR, eepcr); + eepcr |= EEPCR_EECS; + ks8851_wrreg16(ks, KS_EEPCR, eepcr); + mutex_unlock(&ks->lock); + + while (state != EEPROM_COMPLETE) { + /* falling clock period starts... */ + /* set EED_IO pin for control and address */ + eepcr &= ~EEPCR_EEDO; + switch (state) { + case EEPROM_CONTROL: + eepcr |= ((op >> bit_count) & 1) << 2; + if (bit_count-- <= 0) { + bit_count = addr_len - 1; + state = EEPROM_ADDRESS; + } + break; + case EEPROM_ADDRESS: + eepcr |= ((addr >> bit_count) & 1) << 2; + if (bit_count-- <= 0) { + if (op == EEPROM_OP_WRITE) { + bit_count = EEPROM_DATA_LEN - 1; + state = EEPROM_DATA; + } else { + state = EEPROM_COMPLETE; + } + } + break; + case EEPROM_DATA: + eepcr |= ((data >> bit_count) & 1) << 2; + if (bit_count-- <= 0) + state = EEPROM_COMPLETE; + break; + } + + /* lower clock */ + eepcr &= ~EEPCR_EESCK; + + mutex_lock(&ks->lock); + ks8851_wrreg16(ks, KS_EEPCR, eepcr); + mutex_unlock(&ks->lock); + + /* wait period / 2 */ + udelay(EEPROM_SK_PERIOD / 2); + + /* rising clock period starts... */ + + /* raise clock */ + eepcr |= EEPCR_EESCK; + mutex_lock(&ks->lock); + ks8851_wrreg16(ks, KS_EEPCR, eepcr); + mutex_unlock(&ks->lock); + + /* wait period / 2 */ + udelay(EEPROM_SK_PERIOD / 2); + } + + /* close transaction */ + mutex_lock(&ks->lock); + eepcr &= ~EEPCR_EECS; + ks8851_wrreg16(ks, KS_EEPCR, eepcr); + eepcr = 0; + ks8851_wrreg16(ks, KS_EEPCR, eepcr); + mutex_unlock(&ks->lock); + +} + /* ethtool support */ static void ks8851_get_drvinfo(struct net_device *dev, |