This patch fix the i2c deblocking facility with the i2c HW-Controller.
The required delays for byte reading, the enhanced criteria for stop
the dummy read and required 5 start/stop sequences are added.
Add i2c deblocking before ivm eeprom read.
Improve i2c deblocking sequence by respecting stop hold time.
Cleaned function for deblocking. Have now one function i2c_make_abort()
available for bitbang, mpc82xx and mpc83xx harware controller.
Signed-off-by: Stefan Bigler <stefan.big...@keymile.com>
Signed-off-by: Holger Brunck <holger.bru...@keymile.com>
Signed-off-by: Heiko Schocher <h...@denx.de>
cc: Valentin Longchamp <valentin.longch...@keymile.com>
---
board/keymile/common/common.c | 109 ++++++++++++++++++++++++++++++-----------
1 files changed, 80 insertions(+), 29 deletions(-)
diff --git a/board/keymile/common/common.c b/board/keymile/common/common.c
index 5b54e35..03d63c1 100644
--- a/board/keymile/common/common.c
+++ b/board/keymile/common/common.c
@@ -41,6 +41,7 @@
#include <i2c.h>
extern int i2c_soft_read_pin (void);
+extern int i2c_make_abort (void);
int ivm_calc_crc (unsigned char *buf, int len)
{
@@ -325,6 +326,9 @@ int ivm_read_eeprom (void)
if (buf != NULL)
dev_addr = simple_strtoul ((char *)buf, NULL, 16);
+ /* add deblocking here */
+ i2c_make_abort();
+
if (i2c_read(dev_addr, 0, 1, i2c_buffer, CONFIG_SYS_IVM_EEPROM_MAX_LEN)
!= 0) {
printf ("Error reading EEprom\n");
return -2;
@@ -334,7 +338,7 @@ int ivm_read_eeprom (void)
}
#if defined(CONFIG_SYS_I2C_INIT_BOARD)
-#define DELAY_ABORT_SEQ 62
+#define DELAY_ABORT_SEQ 62 /* @200kHz 9 clocks = 44us, 62us is
ok */
#define DELAY_HALF_PERIOD (500 / (CONFIG_SYS_I2C_SPEED / 1000))
#if defined(CONFIG_MGCOGE) || defined(CONFIG_MGCOGE2NE)
@@ -445,8 +449,21 @@ static void writeStartSeq (void)
This I2C Deblocking mechanism was developed by Keymile in association
with Anatech and Atmel in 1998.
*/
-static int i2c_make_abort (void)
+int i2c_make_abort (void)
{
+
+#if defined(CONFIG_HARD_I2C) && !defined(CONFIG_MACH_SUEN3)
+ volatile immap_t *immap = (immap_t *)CONFIG_SYS_IMMR ;
+ volatile i2c8260_t *i2c = (i2c8260_t *)&immap->im_i2c;
+
+ /* disable I2C controller first, otherwhise it thinks we want to */
+ /* talk to the slave port... */
+ i2c->i2c_i2mod &= ~0x01;
+
+ /* Set the PortPins to GPIO */
+ setports (1);
+#endif
+
int scl_state = 0;
int sda_state = 0;
int i = 0;
@@ -473,54 +490,88 @@ static int i2c_make_abort (void)
writeStartSeq ();
}
}
+
+ /* respect stop setup time */
+ udelay (DELAY_ABORT_SEQ);
+ set_scl(1);
+ udelay (DELAY_ABORT_SEQ);
+ set_sda(1);
get_sda ();
+
+#if defined(CONFIG_HARD_I2C)
+ /* Set the PortPins back to use for I2C */
+ setports (0);
+#endif
return ret;
}
#endif
-/**
- * i2c_init_board - reset i2c bus. When the board is powercycled during a
- * bus transfer it might hang; for details see doc/I2C_Edge_Conditions.
- */
-void i2c_init_board(void)
-{
#if defined(CONFIG_MPC83xx)
+static void writeStartSeq (void)
+{
+ struct fsl_i2c *dev;
+ dev = (struct fsl_i2c *) (CONFIG_SYS_IMMR + CONFIG_SYS_I2C_OFFSET);
+ udelay(DELAY_ABORT_SEQ);
+ out_8 (&dev->cr, (I2C_CR_MEN | I2C_CR_MSTA));
+ udelay(DELAY_ABORT_SEQ);
+ out_8 (&dev->cr, (I2C_CR_MEN));
+}
+
+int i2c_make_abort (void)
+{
struct fsl_i2c *dev;
dev = (struct fsl_i2c *) (CONFIG_SYS_IMMR + CONFIG_SYS_I2C_OFFSET);
uchar dummy;
+ uchar last;
+ int nbr_read = 0;
+ int i = 0;
+ int ret = 0;
+ /* wait after each operation to finsh with a delay */
out_8 (&dev->cr, (I2C_CR_MSTA));
+ udelay(DELAY_ABORT_SEQ);
out_8 (&dev->cr, (I2C_CR_MEN | I2C_CR_MSTA));
+ udelay(DELAY_ABORT_SEQ);
dummy = in_8(&dev->dr);
- dummy = in_8(&dev->dr);
- if (dummy != 0xff) {
- dummy = in_8(&dev->dr);
+ udelay(DELAY_ABORT_SEQ);
+ last = in_8(&dev->dr);
+ nbr_read++;
+
+ /* do read until the last bit is 1, but stop if the full eeprom is read
*/
+ while (((last & 0x01) != 0x01) && (nbr_read <
CONFIG_SYS_IVM_EEPROM_MAX_LEN)) {
+ udelay(DELAY_ABORT_SEQ);
+ last = in_8(&dev->dr);
+ nbr_read++;
}
+ if ((last & 0x01) != 0x01)
+ ret = -2;
+ if ((last != 0xff) || (nbr_read > 1))
+ printf("[INFO] i2c abort after %d bytes (0x%02x)\n", nbr_read,
last);
+ udelay(DELAY_ABORT_SEQ);
out_8 (&dev->cr, (I2C_CR_MEN));
- out_8 (&dev->cr, 0x00);
- out_8 (&dev->cr, (I2C_CR_MEN));
+ udelay(DELAY_ABORT_SEQ);
+ /* clear status reg */
+ out_8 (&dev->sr, 0);
-#else
-#if defined(CONFIG_HARD_I2C) && !defined(MACH_TYPE_KM_KIRKWOOD)
- volatile immap_t *immap = (immap_t *)CONFIG_SYS_IMMR ;
- volatile i2c8260_t *i2c = (i2c8260_t *)&immap->im_i2c;
-
- /* disable I2C controller first, otherwhise it thinks we want to */
- /* talk to the slave port... */
- i2c->i2c_i2mod &= ~0x01;
+ for (i = 0; i < 5; i++) {
+ writeStartSeq ();
+ }
+ if (ret != 0) {
+ printf("[ERROR] i2c abort failed after %d bytes (0x%02x)\n",
nbr_read, last);
+ }
+ return ret;
+}
- /* Set the PortPins to GPIO */
- setports (1);
#endif
+/**
+ * i2c_init_board - reset i2c bus. When the board is powercycled during a
+ * bus transfer it might hang; for details see doc/I2C_Edge_Conditions.
+ */
+void i2c_init_board(void)
+{
/* Now run the AbortSequence() */
i2c_make_abort ();
-
-#if defined(CONFIG_HARD_I2C)
- /* Set the PortPins back to use for I2C */
- setports (0);
-#endif
-#endif
}
#endif
#endif
--
1.7.4
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