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-rw-r--r--drivers/i2c/Makefile1
-rw-r--r--drivers/i2c/bfin-twi_i2c.c74
-rw-r--r--drivers/i2c/pca9564_i2c.c189
-rw-r--r--include/pca9564.h50
4 files changed, 300 insertions, 14 deletions
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index 4a12976e3..b860e89f8 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -33,6 +33,7 @@ COBJS-$(CONFIG_I2C_MXC) += mxc_i2c.o
COBJS-$(CONFIG_DRIVER_OMAP1510_I2C) += omap1510_i2c.o
COBJS-$(CONFIG_DRIVER_OMAP24XX_I2C) += omap24xx_i2c.o
COBJS-$(CONFIG_DRIVER_OMAP34XX_I2C) += omap24xx_i2c.o
+COBJS-$(CONFIG_PCA9564_I2C) += pca9564_i2c.o
COBJS-$(CONFIG_DRIVER_S3C24X0_I2C) += s3c24x0_i2c.o
COBJS-$(CONFIG_S3C44B0_I2C) += s3c44b0_i2c.o
COBJS-$(CONFIG_SOFT_I2C) += soft_i2c.o
diff --git a/drivers/i2c/bfin-twi_i2c.c b/drivers/i2c/bfin-twi_i2c.c
index e79063407..73a78d223 100644
--- a/drivers/i2c/bfin-twi_i2c.c
+++ b/drivers/i2c/bfin-twi_i2c.c
@@ -26,6 +26,7 @@
#ifdef TWI0_CLKDIV
#define bfin_write_TWI_CLKDIV(val) bfin_write_TWI0_CLKDIV(val)
+#define bfin_read_TWI_CLKDIV(val) bfin_read_TWI0_CLKDIV(val)
#define bfin_write_TWI_CONTROL(val) bfin_write_TWI0_CONTROL(val)
#define bfin_read_TWI_CONTROL(val) bfin_read_TWI0_CONTROL(val)
#define bfin_write_TWI_MASTER_ADDR(val) bfin_write_TWI0_MASTER_ADDR(val)
@@ -44,8 +45,21 @@
#ifdef CONFIG_TWICLK_KHZ
# error do not define CONFIG_TWICLK_KHZ ... use CONFIG_SYS_I2C_SPEED
#endif
-#if CONFIG_SYS_I2C_SPEED > 400000
-# error The Blackfin I2C hardware can only operate at 400KHz max
+
+/*
+ * The way speed is changed into duty often results in integer truncation
+ * with 50% duty, so we'll force rounding up to the next duty by adding 1
+ * to the max. In practice this will get us a speed of something like
+ * 385 KHz. The other limit is easy to handle as it is only 8 bits.
+ */
+#define I2C_SPEED_MAX 400000
+#define I2C_SPEED_TO_DUTY(speed) (5000000 / (speed))
+#define I2C_DUTY_MAX (I2C_SPEED_TO_DUTY(I2C_SPEED_MAX) + 1)
+#define I2C_DUTY_MIN 0xff /* 8 bit limited */
+#define SYS_I2C_DUTY I2C_SPEED_TO_DUTY(CONFIG_SYS_I2C_SPEED)
+/* Note: duty is inverse of speed, so the comparisons below are correct */
+#if SYS_I2C_DUTY < I2C_DUTY_MAX || SYS_I2C_DUTY > I2C_DUTY_MIN
+# error "The Blackfin I2C hardware can only operate 20KHz - 400KHz"
#endif
/* All transfers are described by this data structure */
@@ -60,6 +74,9 @@ struct i2c_msg {
u8 *abuf; /* addr buffer */
};
+/* Allow msec timeout per ~byte transfer */
+#define I2C_TIMEOUT 10
+
/**
* wait_for_completion - manage the actual i2c transfer
* @msg: the i2c msg
@@ -67,8 +84,9 @@ struct i2c_msg {
static int wait_for_completion(struct i2c_msg *msg)
{
uint16_t int_stat;
+ ulong timebase = get_timer(0);
- while (!ctrlc()) {
+ do {
int_stat = bfin_read_TWI_INT_STAT();
if (int_stat & XMTSERV) {
@@ -103,7 +121,7 @@ static int wait_for_completion(struct i2c_msg *msg)
debugi("processing MERR");
bfin_write_TWI_INT_STAT(MERR);
SSYNC();
- break;
+ return msg->len;
}
if (int_stat & MCOMP) {
debugi("processing MCOMP");
@@ -116,7 +134,12 @@ static int wait_for_completion(struct i2c_msg *msg)
} else
break;
}
- }
+
+ /* If we were able to do something, reset timeout */
+ if (int_stat)
+ timebase = get_timer(0);
+
+ } while (get_timer(timebase) < I2C_TIMEOUT);
return msg->len;
}
@@ -204,7 +227,36 @@ static int i2c_transfer(uchar chip, uint addr, int alen, uchar *buffer, int len,
return ret;
}
-/*
+/**
+ * i2c_set_bus_speed - set i2c bus speed
+ * @speed: bus speed (in HZ)
+ */
+int i2c_set_bus_speed(unsigned int speed)
+{
+ u16 clkdiv = I2C_SPEED_TO_DUTY(speed);
+
+ /* Set TWI interface clock */
+ if (clkdiv < I2C_DUTY_MAX || clkdiv > I2C_DUTY_MIN)
+ return -1;
+ bfin_write_TWI_CLKDIV((clkdiv << 8) | (clkdiv & 0xff));
+
+ /* Don't turn it on */
+ bfin_write_TWI_MASTER_CTL(speed > 100000 ? FAST : 0);
+
+ return 0;
+}
+
+/**
+ * i2c_get_bus_speed - get i2c bus speed
+ * @speed: bus speed (in HZ)
+ */
+unsigned int i2c_get_bus_speed(void)
+{
+ /* 10 MHz / (2 * CLKDIV) -> 5 MHz / CLKDIV */
+ return 5000000 / (bfin_read_TWI_CLKDIV() & 0xff);
+}
+
+/**
* i2c_init - initialize the i2c bus
* @speed: bus speed (in HZ)
* @slaveaddr: address of device in slave mode (0 - not slave)
@@ -220,15 +272,9 @@ void i2c_init(int speed, int slaveaddr)
bfin_write_TWI_CONTROL(prescale);
/* Set TWI interface clock as specified */
- bfin_write_TWI_CLKDIV(
- ((5 * 1024 / (speed / 1000)) << 8) |
- ((5 * 1024 / (speed / 1000)) & 0xFF)
- );
-
- /* Don't turn it on */
- bfin_write_TWI_MASTER_CTL(speed > 100000 ? FAST : 0);
+ i2c_set_bus_speed(speed);
- /* But enable it */
+ /* Enable it */
bfin_write_TWI_CONTROL(TWI_ENA | prescale);
SSYNC();
diff --git a/drivers/i2c/pca9564_i2c.c b/drivers/i2c/pca9564_i2c.c
new file mode 100644
index 000000000..199a9ee39
--- /dev/null
+++ b/drivers/i2c/pca9564_i2c.c
@@ -0,0 +1,189 @@
+/*
+ * File: drivers/i2c/pca9564.c
+ * Based on: drivers/i2c/s3c44b0_i2c.c
+ * Author:
+ *
+ * Created: 2009-06-23
+ * Description: PCA9564 i2c bridge driver
+ *
+ * Modified:
+ * Copyright 2009 CJSC "NII STT", http://www.niistt.ru/
+ *
+ * Bugs:
+ *
+ * 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, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <common.h>
+#include <i2c.h>
+#include <pca9564.h>
+#include <asm/io.h>
+
+#define PCA_STA (CONFIG_PCA9564_BASE + 0)
+#define PCA_TO (CONFIG_PCA9564_BASE + 0)
+#define PCA_DAT (CONFIG_PCA9564_BASE + (1 << 2))
+#define PCA_ADR (CONFIG_PCA9564_BASE + (2 << 2))
+#define PCA_CON (CONFIG_PCA9564_BASE + (3 << 2))
+
+static unsigned char pca_read_reg(unsigned int reg)
+{
+ return readb((void *)reg);
+}
+
+static void pca_write_reg(unsigned int reg, unsigned char value)
+{
+ writeb(value, (void *)reg);
+}
+
+static int pca_wait_busy(void)
+{
+ unsigned int timeout = 10000;
+
+ while (!(pca_read_reg(PCA_CON) & PCA_CON_SI) && --timeout)
+ udelay(1);
+
+ if (timeout == 0)
+ debug("I2C timeout!\n");
+
+ debug("CON = 0x%02x, STA = 0x%02x\n", pca_read_reg(PCA_CON),
+ pca_read_reg(PCA_STA));
+
+ return timeout ? 0 : 1;
+}
+
+/*=====================================================================*/
+/* Public Functions */
+/*=====================================================================*/
+
+/*-----------------------------------------------------------------------
+ * Initialization
+ */
+void i2c_init(int speed, int slaveaddr)
+{
+ pca_write_reg(PCA_CON, PCA_CON_ENSIO | speed);
+}
+
+/*
+ * Probe the given I2C chip address. Returns 0 if a chip responded,
+ * not 0 on failure.
+ */
+
+int i2c_probe(uchar chip)
+{
+ unsigned char res;
+
+ pca_write_reg(PCA_CON, PCA_CON_STA | PCA_CON_ENSIO);
+ pca_wait_busy();
+
+ pca_write_reg(PCA_CON, PCA_CON_STA | PCA_CON_ENSIO);
+
+ pca_write_reg(PCA_DAT, (chip << 1) | 1);
+ res = pca_wait_busy();
+
+ if ((res == 0) && (pca_read_reg(PCA_STA) == 0x48))
+ res = 1;
+
+ pca_write_reg(PCA_CON, PCA_CON_STO | PCA_CON_ENSIO);
+
+ return res;
+}
+
+/*
+ * 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
+ */
+int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
+{
+ int i;
+
+ pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_STA);
+ pca_wait_busy();
+
+ pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+
+ pca_write_reg(PCA_DAT, (chip << 1));
+ pca_wait_busy();
+ pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+
+ if (alen > 0) {
+ pca_write_reg(PCA_DAT, addr);
+ pca_wait_busy();
+ pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+ }
+
+ pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_STO);
+
+ udelay(500);
+
+ pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_STA);
+ pca_wait_busy();
+ pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+
+ pca_write_reg(PCA_DAT, (chip << 1) | 1);
+ pca_wait_busy();
+
+ for (i = 0; i < len; ++i) {
+ if (i == len - 1)
+ pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+ else
+ pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_AA);
+
+ pca_wait_busy();
+ buffer[i] = pca_read_reg(PCA_DAT);
+
+ }
+
+ pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_STO);
+
+ return 0;
+}
+
+int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
+{
+ int i;
+
+ pca_write_reg(PCA_CON, PCA_CON_ENSIO | PCA_CON_STA);
+ pca_wait_busy();
+ pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+
+ pca_write_reg(PCA_DAT, chip << 1);
+ pca_wait_busy();
+ pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+
+ if (alen > 0) {
+ pca_write_reg(PCA_DAT, addr);
+ pca_wait_busy();
+ pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+ }
+
+ for (i = 0; i < len; ++i) {
+ pca_write_reg(PCA_DAT, buffer[i]);
+ pca_wait_busy();
+ pca_write_reg(PCA_CON, PCA_CON_ENSIO);
+ }
+
+ pca_write_reg(PCA_CON, PCA_CON_STO | PCA_CON_ENSIO);
+
+ return 0;
+}
diff --git a/include/pca9564.h b/include/pca9564.h
new file mode 100644
index 000000000..3e75259e0
--- /dev/null
+++ b/include/pca9564.h
@@ -0,0 +1,50 @@
+/*
+ * File: include/pca9564.h
+ * Author:
+ *
+ * Created: 2009-06-23
+ * Description: PCA9564 i2c bridge driver
+ *
+ * Modified:
+ * Copyright 2009 CJSC "NII STT", http://www.niistt.ru/
+ *
+ * Bugs:
+ *
+ * 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, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef _PCA9564_H
+#define _PCA9564_H
+
+/* Clock speeds for the bus */
+#define PCA_CON_330kHz 0x00
+#define PCA_CON_288kHz 0x01
+#define PCA_CON_217kHz 0x02
+#define PCA_CON_146kHz 0x03
+#define PCA_CON_88kHz 0x04
+#define PCA_CON_59kHz 0x05
+#define PCA_CON_44kHz 0x06
+#define PCA_CON_36kHz 0x07
+
+#define PCA_CON_AA 0x80 /* Assert Acknowledge */
+#define PCA_CON_ENSIO 0x40 /* Enable */
+#define PCA_CON_STA 0x20 /* Start */
+#define PCA_CON_STO 0x10 /* Stop */
+#define PCA_CON_SI 0x08 /* Serial Interrupt */
+#define PCA_CON_CR 0x07 /* Clock Rate (MASK) */
+
+#endif
+
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