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Diffstat (limited to 'drivers/i2c/s3c44b0_i2c.c')
-rw-r--r--drivers/i2c/s3c44b0_i2c.c315
1 files changed, 315 insertions, 0 deletions
diff --git a/drivers/i2c/s3c44b0_i2c.c b/drivers/i2c/s3c44b0_i2c.c
new file mode 100644
index 0000000..b4d904b
--- /dev/null
+++ b/drivers/i2c/s3c44b0_i2c.c
@@ -0,0 +1,315 @@
+/*
+ * (C) Copyright 2004
+ * DAVE Srl
+ * http://www.dave-tech.it
+ * http://www.wawnet.biz
+ * mailto:info@wawnet.biz
+ *
+ * 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 <command.h>
+#include <asm/hardware.h>
+
+/*
+ * Initialization, must be called once on start up, may be called
+ * repeatedly to change the speed and slave addresses.
+ */
+void i2c_init(int speed, int slaveaddr)
+{
+ /*
+ setting up I2C support
+ */
+ unsigned int save_F,save_PF,rIICCON,rPCONA,rPDATA,rPCONF,rPUPF;
+
+ save_F = PCONF;
+ save_PF = PUPF;
+
+ rPCONF = ((save_F & ~(0xF))| 0xa);
+ rPUPF = (save_PF | 0x3);
+ PCONF = rPCONF; /*PF0:IICSCL, PF1:IICSDA*/
+ PUPF = rPUPF; /* Disable pull-up */
+
+ /* Configuring pin for WC pin of EEprom */
+ rPCONA = PCONA;
+ rPCONA &= ~(1<<9);
+ PCONA = rPCONA;
+
+ rPDATA = PDATA;
+ rPDATA &= ~(1<<9);
+ PDATA = rPDATA;
+
+ /*
+ Enable ACK, IICCLK=MCLK/16, enable interrupt
+ 75MHz/16/(12+1) = 390625 Hz
+ */
+ rIICCON=(1<<7)|(0<<6)|(1<<5)|(0xC);
+ IICCON = rIICCON;
+
+ IICADD = slaveaddr;
+}
+
+/*
+ * Probe the given I2C chip address. Returns 0 if a chip responded,
+ * not 0 on failure.
+ */
+int i2c_probe(uchar chip)
+{
+ /*
+ not implemented
+ */
+
+ printf("i2c_probe chip %d\n", (int) chip);
+ return -1;
+}
+
+/*
+ * Read/Write interface:
+ * chip: I2C chip address, range 0..127
+ * addr: Memory (register) address within the chip
+ * alen: Number of bytes to use for addr (typically 1, 2 for larger
+ * memories, 0 for register type devices with only one
+ * register)
+ * buffer: Where to read/write the data
+ * len: How many bytes to read/write
+ *
+ * Returns: 0 on success, not 0 on failure
+ */
+
+#define S3C44B0X_rIIC_INTPEND (1<<4)
+#define S3C44B0X_rIIC_LAST_RECEIV_BIT (1<<0)
+#define S3C44B0X_rIIC_INTERRUPT_ENABLE (1<<5)
+#define S3C44B0_IIC_TIMEOUT 100
+
+int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
+{
+
+ int k, j, temp;
+ u32 rIICSTAT;
+
+ /*
+ send the device offset
+ */
+
+ rIICSTAT = 0xD0;
+ IICSTAT = rIICSTAT;
+
+ IICDS = chip; /* this is a write operation... */
+
+ rIICSTAT |= (1<<5);
+ IICSTAT = rIICSTAT;
+
+ for(k=0; k<S3C44B0_IIC_TIMEOUT; k++) {
+ temp = IICCON;
+ if( (temp & S3C44B0X_rIIC_INTPEND) == S3C44B0X_rIIC_INTPEND)
+ break;
+ udelay(2000);
+ }
+ if (k==S3C44B0_IIC_TIMEOUT)
+ return -1;
+
+ /* wait and check ACK */
+ temp = IICSTAT;
+ if ((temp & S3C44B0X_rIIC_LAST_RECEIV_BIT) == S3C44B0X_rIIC_LAST_RECEIV_BIT )
+ return -1;
+
+ IICDS = addr;
+ IICCON = IICCON & ~(S3C44B0X_rIIC_INTPEND);
+
+ /* wait and check ACK */
+ for(k=0; k<S3C44B0_IIC_TIMEOUT; k++) {
+ temp = IICCON;
+ if( (temp & S3C44B0X_rIIC_INTPEND) == S3C44B0X_rIIC_INTPEND)
+ break;
+ udelay(2000);
+ }
+ if (k==S3C44B0_IIC_TIMEOUT)
+ return -1;
+
+ temp = IICSTAT;
+ if ((temp & S3C44B0X_rIIC_LAST_RECEIV_BIT) == S3C44B0X_rIIC_LAST_RECEIV_BIT )
+ return -1;
+
+ /*
+ now we can start with the read operation...
+ */
+
+ IICDS = chip | 0x01; /* this is a read operation... */
+
+ rIICSTAT = 0x90; /*master recv*/
+ rIICSTAT |= (1<<5);
+ IICSTAT = rIICSTAT;
+
+ IICCON = IICCON & ~(S3C44B0X_rIIC_INTPEND);
+
+ /* wait and check ACK */
+ for(k=0; k<S3C44B0_IIC_TIMEOUT; k++) {
+ temp = IICCON;
+ if( (temp & S3C44B0X_rIIC_INTPEND) == S3C44B0X_rIIC_INTPEND)
+ break;
+ udelay(2000);
+ }
+ if (k==S3C44B0_IIC_TIMEOUT)
+ return -1;
+
+ temp = IICSTAT;
+ if ((temp & S3C44B0X_rIIC_LAST_RECEIV_BIT) == S3C44B0X_rIIC_LAST_RECEIV_BIT )
+ return -1;
+
+ for (j=0; j<len-1; j++) {
+
+ /*clear pending bit to resume */
+
+ temp = IICCON & ~(S3C44B0X_rIIC_INTPEND);
+ IICCON = temp;
+
+ /* wait and check ACK */
+ for(k=0; k<S3C44B0_IIC_TIMEOUT; k++) {
+ temp = IICCON;
+ if( (temp & S3C44B0X_rIIC_INTPEND) == S3C44B0X_rIIC_INTPEND)
+ break;
+ udelay(2000);
+ }
+ if (k==S3C44B0_IIC_TIMEOUT)
+ return -1;
+
+
+ buffer[j] = IICDS; /*save readed data*/
+
+ } /*end for(j)*/
+
+ /*
+ reading the last data
+ unset ACK generation
+ */
+ temp = IICCON & ~(S3C44B0X_rIIC_INTPEND | (1<<7));
+ IICCON = temp;
+
+ /* wait but NOT check ACK */
+ for(k=0; k<S3C44B0_IIC_TIMEOUT; k++) {
+ temp = IICCON;
+ if( (temp & S3C44B0X_rIIC_INTPEND) == S3C44B0X_rIIC_INTPEND)
+ break;
+ udelay(2000);
+ }
+ if (k==S3C44B0_IIC_TIMEOUT)
+ return -1;
+
+ buffer[j] = IICDS; /*save readed data*/
+
+ rIICSTAT = 0x90; /*master recv*/
+
+ /* Write operation Terminate sending STOP */
+ IICSTAT = rIICSTAT;
+ /*Clear Int Pending Bit to RESUME*/
+ temp = IICCON;
+ IICCON = temp & (~S3C44B0X_rIIC_INTPEND);
+
+ IICCON = IICCON | (1<<7); /*restore ACK generation*/
+
+ return 0;
+}
+
+int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
+{
+ int j, k;
+ u32 rIICSTAT, temp;
+
+
+ /*
+ send the device offset
+ */
+
+ rIICSTAT = 0xD0;
+ IICSTAT = rIICSTAT;
+
+ IICDS = chip; /* this is a write operation... */
+
+ rIICSTAT |= (1<<5);
+ IICSTAT = rIICSTAT;
+
+ IICCON = IICCON & ~(S3C44B0X_rIIC_INTPEND);
+
+ /* wait and check ACK */
+ for(k=0; k<S3C44B0_IIC_TIMEOUT; k++) {
+ temp = IICCON;
+ if( (temp & S3C44B0X_rIIC_INTPEND) == S3C44B0X_rIIC_INTPEND)
+ break;
+ udelay(2000);
+ }
+ if (k==S3C44B0_IIC_TIMEOUT)
+ return -1;
+
+ temp = IICSTAT;
+ if ((temp & S3C44B0X_rIIC_LAST_RECEIV_BIT) == S3C44B0X_rIIC_LAST_RECEIV_BIT )
+ return -1;
+
+ IICDS = addr;
+ IICCON = IICCON & ~(S3C44B0X_rIIC_INTPEND);
+
+ /* wait and check ACK */
+ for(k=0; k<S3C44B0_IIC_TIMEOUT; k++) {
+ temp = IICCON;
+ if( (temp & S3C44B0X_rIIC_INTPEND) == S3C44B0X_rIIC_INTPEND)
+ break;
+ udelay(2000);
+ }
+ if (k==S3C44B0_IIC_TIMEOUT)
+ return -1;
+
+ temp = IICSTAT;
+ if ((temp & S3C44B0X_rIIC_LAST_RECEIV_BIT) == S3C44B0X_rIIC_LAST_RECEIV_BIT )
+ return -1;
+
+ /*
+ now we can start with the read write operation
+ */
+ for (j=0; j<len; j++) {
+
+ IICDS = buffer[j]; /*prerare data to write*/
+
+ /*clear pending bit to resume*/
+
+ temp = IICCON & ~(S3C44B0X_rIIC_INTPEND);
+ IICCON = temp;
+
+ /* wait but NOT check ACK */
+ for(k=0; k<S3C44B0_IIC_TIMEOUT; k++) {
+ temp = IICCON;
+ if( (temp & S3C44B0X_rIIC_INTPEND) == S3C44B0X_rIIC_INTPEND)
+ break;
+
+ udelay(2000);
+ }
+
+ if (k==S3C44B0_IIC_TIMEOUT)
+ return -1;
+
+ } /* end for(j) */
+
+ /* sending stop to terminate */
+ rIICSTAT = 0xD0; /*master send*/
+ IICSTAT = rIICSTAT;
+ /*Clear Int Pending Bit to RESUME*/
+ temp = IICCON;
+ IICCON = temp & (~S3C44B0X_rIIC_INTPEND);
+
+ return 0;
+}