* (C) Copyright 2001
* Bill Hunter, Wave 7 Optics, williamhunter@mediaone.net
*
- * See file CREDITS for list of people who contributed to this
- * project.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of
- * the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
- * MA 02111-1307 USA
+ * SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
*
* Typical case is a Write of an addr followd by a Read. The
* IBM FAQ does not cover this. On the last byte of the write
- * we don't set the creg CHT bit, and on the first bytes of the
- * read we set the RPST bit.
+ * we don't set the creg CHT bit but the RPST bit.
*
* It does not support address only transfers, there must be
* a data part. If you want to write the address yourself, put
if ((!cmd_type && (ptr == addr)) || ((tran + bc) != cnt))
creg |= IIC_CNTL_CHT;
+ /* last part of address, prepare for repeated start on read */
+ if (cmd_type && (ptr == addr) && ((tran + bc) == cnt))
+ creg |= IIC_CNTL_RPST;
+
if (reading) {
creg |= IIC_CNTL_READ;
} else {
/* Transfer aborted? */
if (status & IIC_EXTSTS_XFRA)
result = IIC_NOK_XFRA;
+ /* Is bus free?
+ * If error happened during combined xfer
+ * IIC interface is usually stuck in some strange
+ * state without a valid stop condition.
+ * Brute, but working: generate stop, then soft reset.
+ */
+ if ((status & IIC_EXTSTS_BCS_MASK)
+ != IIC_EXTSTS_BCS_FREE){
+ u8 mdcntl = in_8(&i2c->mdcntl);
+
+ /* Generate valid stop condition */
+ out_8(&i2c->xtcntlss, IIC_XTCNTLSS_SRST);
+ out_8(&i2c->directcntl, IIC_DIRCNTL_SCC);
+ udelay(10);
+ out_8(&i2c->directcntl,
+ IIC_DIRCNTL_SCC | IIC_DIRCNTL_SDAC);
+ out_8(&i2c->xtcntlss, 0);
+
+ ppc4xx_i2c_init(adap, (mdcntl & IIC_MDCNTL_FSM)
+ ? 400000 : 100000, 0);
+ }
} else if ( status & IIC_STS_PT) {
result = IIC_NOK_TOUT;
}
cnt = data_len;
tran = 0;
reading = cmd_type;
- if (reading)
- creg = IIC_CNTL_RPST;
}
}
return result;