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authorSebastien Jan <s-jan@ti.com>2010-05-05 08:45:53 +0000
committerDavid S. Miller <davem@davemloft.net>2010-05-05 21:27:44 -0700
commita4bdfff74464f86d7e3b8feaf42d18960adc5514 (patch)
tree4dcde38694ca796b1a3d04a0044948397b497f6c /drivers/net/ks8851.c
parent7d9974666e0dc2cbbeac80fa4d550df0bbea6fad (diff)
downloadlinux-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.c228
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,