i2c: Move PPC4xx I2C driver into drivers/i2c directory

This patch moves the PPC4xx specific I2C device driver into the I2C
drivers directory. All 4xx config headers are updated to include this
driver.

Signed-off-by: Stefan Roese <sr@denx.de>

1 files changed, 439 insertions, 0 deletions

diff --git a/drivers/i2c/ppc4xx_i2c.c b/drivers/i2c/ppc4xx_i2c.c
new file mode 100644
index 0000000..9b86187
--- /dev/null
+++ b/drivers/i2c/ppc4xx_i2c.c
@@ -0,0 +1,439 @@
+/*
+ * (C) Copyright 2007-2009
+ * Stefan Roese, DENX Software Engineering, sr@denx.de.
+ *
+ * based on work by Anne Sophie Harnois <anne-sophie.harnois@nextream.fr>
+ *
+ * (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
+ */
+
+#include <common.h>
+#include <ppc4xx.h>
+#include <4xx_i2c.h>
+#include <i2c.h>
+#include <asm-ppc/io.h>
+
+#ifdef CONFIG_HARD_I2C
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#if defined(CONFIG_I2C_MULTI_BUS)
+/*
+ * Initialize the bus pointer to whatever one the SPD EEPROM is on.
+ * Default is bus 0.  This is necessary because the DDR initialization
+ * runs from ROM, and we can't switch buses because we can't modify
+ * the global variables.
+ */
+#ifndef CONFIG_SYS_SPD_BUS_NUM
+#define CONFIG_SYS_SPD_BUS_NUM	0
+#endif
+static unsigned int i2c_bus_num __attribute__ ((section (".data"))) =
+	CONFIG_SYS_SPD_BUS_NUM;
+#endif /* CONFIG_I2C_MULTI_BUS */
+
+static void _i2c_bus_reset(void)
+{
+	struct ppc4xx_i2c *i2c = (struct ppc4xx_i2c *)I2C_BASE_ADDR;
+	int i;
+	u8 dc;
+
+	/* Reset status register */
+	/* write 1 in SCMP and IRQA to clear these fields */
+	out_8(&i2c->sts, 0x0A);
+
+	/* write 1 in IRQP IRQD LA ICT XFRA to clear these fields */
+	out_8(&i2c->extsts, 0x8F);
+
+	/* Place chip in the reset state */
+	out_8(&i2c->xtcntlss, IIC_XTCNTLSS_SRST);
+
+	/* Check if bus is free */
+	dc = in_8(&i2c->directcntl);
+	if (!DIRCTNL_FREE(dc)){
+		/* Try to set bus free state */
+		out_8(&i2c->directcntl, IIC_DIRCNTL_SDAC | IIC_DIRCNTL_SCC);
+
+		/* Wait until we regain bus control */
+		for (i = 0; i < 100; ++i) {
+			dc = in_8(&i2c->directcntl);
+			if (DIRCTNL_FREE(dc))
+				break;
+
+			/* Toggle SCL line */
+			dc ^= IIC_DIRCNTL_SCC;
+			out_8(&i2c->directcntl, dc);
+			udelay(10);
+			dc ^= IIC_DIRCNTL_SCC;
+			out_8(&i2c->directcntl, dc);
+		}
+	}
+
+	/* Remove reset */
+	out_8(&i2c->xtcntlss, 0);
+}
+
+void i2c_init(int speed, int slaveaddr)
+{
+	struct ppc4xx_i2c *i2c;
+	int val, divisor;
+	int bus;
+
+#ifdef CONFIG_SYS_I2C_INIT_BOARD
+	/*
+	 * Call board specific i2c bus reset routine before accessing the
+	 * environment, which might be in a chip on that bus. For details
+	 * about this problem see doc/I2C_Edge_Conditions.
+	 */
+	i2c_init_board();
+#endif
+
+	for (bus = 0; bus < CONFIG_SYS_MAX_I2C_BUS; bus++) {
+		I2C_SET_BUS(bus);
+
+		/* Set i2c pointer after calling I2C_SET_BUS() */
+		i2c = (struct ppc4xx_i2c *)I2C_BASE_ADDR;
+
+		/* Handle possible failed I2C state */
+		/* FIXME: put this into i2c_init_board()? */
+		_i2c_bus_reset();
+
+		/* clear lo master address */
+		out_8(&i2c->lmadr, 0);
+
+		/* clear hi master address */
+		out_8(&i2c->hmadr, 0);
+
+		/* clear lo slave address */
+		out_8(&i2c->lsadr, 0);
+
+		/* clear hi slave address */
+		out_8(&i2c->hsadr, 0);
+
+		/* Clock divide Register */
+		/* set divisor according to freq_opb */
+		divisor = (get_OPB_freq() - 1) / 10000000;
+		if (divisor == 0)
+			divisor = 1;
+		out_8(&i2c->clkdiv, divisor);
+
+		/* no interrupts */
+		out_8(&i2c->intrmsk, 0);
+
+		/* clear transfer count */
+		out_8(&i2c->xfrcnt, 0);
+
+		/* clear extended control & stat */
+		/* write 1 in SRC SRS SWC SWS to clear these fields */
+		out_8(&i2c->xtcntlss, 0xF0);
+
+		/* Mode Control Register
+		   Flush Slave/Master data buffer */
+		out_8(&i2c->mdcntl, IIC_MDCNTL_FSDB | IIC_MDCNTL_FMDB);
+
+		val = in_8(&i2c->mdcntl);
+
+		/* Ignore General Call, slave transfers are ignored,
+		 * disable interrupts, exit unknown bus state, enable hold
+		 * SCL 100kHz normaly or FastMode for 400kHz and above
+		 */
+
+		val |= IIC_MDCNTL_EUBS | IIC_MDCNTL_HSCL;
+		if (speed >= 400000)
+			val |= IIC_MDCNTL_FSM;
+		out_8(&i2c->mdcntl, val);
+
+		/* clear control reg */
+		out_8(&i2c->cntl, 0x00);
+	}
+
+	/* set to SPD bus as default bus upon powerup */
+	I2C_SET_BUS(CONFIG_SYS_SPD_BUS_NUM);
+}
+
+/*
+ * This code tries to use the features of the 405GP i2c
+ * controller. It will transfer up to 4 bytes in one pass
+ * on the loop. It only does out_8((u8 *)lbz) to the buffer when it
+ * is possible to do out16(lhz) transfers.
+ *
+ * cmd_type is 0 for write 1 for read.
+ *
+ * addr_len can take any value from 0-255, it is only limited
+ * by the char, we could make it larger if needed. If it is
+ * 0 we skip the address write cycle.
+ *
+ * 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.
+ *
+ * It does not support address only transfers, there must be
+ * a data part. If you want to write the address yourself, put
+ * it in the data pointer.
+ *
+ * It does not support transfer to/from address 0.
+ *
+ * It does not check XFRCNT.
+ */
+static int i2c_transfer(unsigned char cmd_type,
+			unsigned char chip,
+			unsigned char addr[],
+			unsigned char addr_len,
+			unsigned char data[],
+			unsigned short data_len)
+{
+	struct ppc4xx_i2c *i2c = (struct ppc4xx_i2c *)I2C_BASE_ADDR;
+	u8 *ptr;
+	int reading;
+	int tran, cnt;
+	int result;
+	int status;
+	int i;
+	u8 creg;
+
+	if (data == 0 || data_len == 0) {
+		/* Don't support data transfer of no length or to address 0 */
+		printf( "i2c_transfer: bad call\n" );
+		return IIC_NOK;
+	}
+	if (addr && addr_len) {
+		ptr = addr;
+		cnt = addr_len;
+		reading = 0;
+	} else {
+		ptr = data;
+		cnt = data_len;
+		reading = cmd_type;
+	}
+
+	/* Clear Stop Complete Bit */
+	out_8(&i2c->sts, IIC_STS_SCMP);
+
+	/* Check init */
+	i = 10;
+	do {
+		/* Get status */
+		status = in_8(&i2c->sts);
+		i--;
+	} while ((status & IIC_STS_PT) && (i > 0));
+
+	if (status & IIC_STS_PT) {
+		result = IIC_NOK_TOUT;
+		return(result);
+	}
+
+	/* flush the Master/Slave Databuffers */
+	out_8(&i2c->mdcntl, in_8(&i2c->mdcntl) |
+	      IIC_MDCNTL_FMDB | IIC_MDCNTL_FSDB);
+
+	/* need to wait 4 OPB clocks? code below should take that long */
+
+	/* 7-bit adressing */
+	out_8(&i2c->hmadr, 0);
+	out_8(&i2c->lmadr, chip);
+
+	tran = 0;
+	result = IIC_OK;
+	creg = 0;
+
+	while (tran != cnt && (result == IIC_OK)) {
+		int  bc,j;
+
+		/*
+		 * Control register =
+		 * Normal transfer, 7-bits adressing, Transfer up to
+		 * bc bytes, Normal start, Transfer is a sequence of transfers
+		 */
+		creg |= IIC_CNTL_PT;
+
+		bc = (cnt - tran) > 4 ? 4 : cnt - tran;
+		creg |= (bc - 1) << 4;
+		/* if the real cmd type is write continue trans */
+		if ((!cmd_type && (ptr == addr)) || ((tran + bc) != cnt))
+			creg |= IIC_CNTL_CHT;
+
+		if (reading) {
+			creg |= IIC_CNTL_READ;
+		} else {
+			for(j = 0; j < bc; j++) {
+				/* Set buffer */
+				out_8(&i2c->mdbuf, ptr[tran + j]);
+			}
+		}
+		out_8(&i2c->cntl, creg);
+
+		/*
+		 * Transfer is in progress
+		 * we have to wait for upto 5 bytes of data
+		 * 1 byte chip address+r/w bit then bc bytes
+		 * of data.
+		 * udelay(10) is 1 bit time at 100khz
+		 * Doubled for slop. 20 is too small.
+		 */
+		i = 2 * 5 * 8;
+		do {
+			/* Get status */
+			status = in_8(&i2c->sts);
+			udelay(10);
+			i--;
+		} while ((status & IIC_STS_PT) && !(status & IIC_STS_ERR) &&
+			 (i > 0));
+
+		if (status & IIC_STS_ERR) {
+			result = IIC_NOK;
+			status = in_8(&i2c->extsts);
+			/* Lost arbitration? */
+			if (status & IIC_EXTSTS_LA)
+				result = IIC_NOK_LA;
+			/* Incomplete transfer? */
+			if (status & IIC_EXTSTS_ICT)
+				result = IIC_NOK_ICT;
+			/* Transfer aborted? */
+			if (status & IIC_EXTSTS_XFRA)
+				result = IIC_NOK_XFRA;
+		} else if ( status & IIC_STS_PT) {
+			result = IIC_NOK_TOUT;
+		}
+
+		/* Command is reading => get buffer */
+		if ((reading) && (result == IIC_OK)) {
+			/* Are there data in buffer */
+			if (status & IIC_STS_MDBS) {
+				/*
+				 * even if we have data we have to wait 4OPB
+				 * clocks for it to hit the front of the FIFO,
+				 * after that we can just read. We should check
+				 * XFCNT here and if the FIFO is full there is
+				 * no need to wait.
+				 */
+				udelay(1);
+				for (j = 0; j < bc; j++)
+					ptr[tran + j] = in_8(&i2c->mdbuf);
+			} else
+				result = IIC_NOK_DATA;
+		}
+		creg = 0;
+		tran += bc;
+		if (ptr == addr && tran == cnt) {
+			ptr = data;
+			cnt = data_len;
+			tran = 0;
+			reading = cmd_type;
+			if (reading)
+				creg = IIC_CNTL_RPST;
+		}
+	}
+	return result;
+}
+
+int i2c_probe(uchar chip)
+{
+	uchar buf[1];
+
+	buf[0] = 0;
+
+	/*
+	 * What is needed is to send the chip address and verify that the
+	 * address was <ACK>ed (i.e. there was a chip at that address which
+	 * drove the data line low).
+	 */
+	return (i2c_transfer(1, chip << 1, 0, 0, buf, 1) != 0);
+}
+
+static int ppc4xx_i2c_transfer(uchar chip, uint addr, int alen, uchar *buffer,
+			       int len, int read)
+{
+	uchar xaddr[4];
+	int ret;
+
+	if (alen > 4) {
+		printf("I2C: addr len %d not supported\n", alen);
+		return 1;
+	}
+
+	if (alen > 0) {
+		xaddr[0] = (addr >> 24) & 0xFF;
+		xaddr[1] = (addr >> 16) & 0xFF;
+		xaddr[2] = (addr >> 8) & 0xFF;
+		xaddr[3] = addr & 0xFF;
+	}
+
+
+#ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
+	/*
+	 * EEPROM chips that implement "address overflow" are ones
+	 * like Catalyst 24WC04/08/16 which has 9/10/11 bits of
+	 * address and the extra bits end up in the "chip address"
+	 * bit slots. This makes a 24WC08 (1Kbyte) chip look like
+	 * four 256 byte chips.
+	 *
+	 * Note that we consider the length of the address field to
+	 * still be one byte because the extra address bits are
+	 * hidden in the chip address.
+	 */
+	if (alen > 0)
+		chip |= ((addr >> (alen * 8)) &
+			 CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
+#endif
+	if ((ret = i2c_transfer(read, chip << 1, &xaddr[4 - alen], alen,
+				buffer, len)) != 0) {
+		if (gd->have_console) {
+			printf("I2C %s: failed %d\n",
+			       read ? "read" : "write", ret);
+		}
+
+		return 1;
+	}
+
+	return 0;
+}
+
+int i2c_read(uchar chip, uint addr, int alen, uchar * buffer, int len)
+{
+	return ppc4xx_i2c_transfer(chip, addr, alen, buffer, len, 1);
+}
+
+int i2c_write(uchar chip, uint addr, int alen, uchar * buffer, int len)
+{
+	return ppc4xx_i2c_transfer(chip, addr, alen, buffer, len, 0);
+}
+
+#if defined(CONFIG_I2C_MULTI_BUS)
+/*
+ * Functions for multiple I2C bus handling
+ */
+unsigned int i2c_get_bus_num(void)
+{
+	return i2c_bus_num;
+}
+
+int i2c_set_bus_num(unsigned int bus)
+{
+	if (bus >= CONFIG_SYS_MAX_I2C_BUS)
+		return -1;
+
+	i2c_bus_num = bus;
+
+	return 0;
+}
+#endif	/* CONFIG_I2C_MULTI_BUS */
+#endif	/* CONFIG_HARD_I2C */