ARMV7: Restructure OMAP i2c driver to allow code sharing between OMAP3 and OMAP4

This patch modifies the omap24xx driver so that it will also work with OMAP4.

Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>

2 files changed, 180 insertions, 3 deletions

diff --git a/drivers/i2c/omap24xx_i2c.c b/drivers/i2c/omap24xx_i2c.c
index ff18991..3256133 100644
--- a/drivers/i2c/omap24xx_i2c.c
+++ b/drivers/i2c/omap24xx_i2c.c
@@ -25,6 +25,8 @@
 #include <asm/arch/i2c.h>
 #include <asm/io.h>
 
+#include "omap24xx_i2c.h"
+
 static void wait_for_bb (void);
 static u16 wait_for_pin (void);
 static void flush_fifo(void);
@@ -176,7 +178,8 @@ static int i2c_read_byte (u8 devaddr, u8 regoffset, u8 * value)
 
 		status = wait_for_pin ();
 		if (status & I2C_STAT_RRDY) {
-#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
+#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
+    defined(CONFIG_OMAP44XX)
 			*value = readb (&i2c_base->data);
 #else
 			*value = readw (&i2c_base->data);
@@ -221,7 +224,8 @@ static int i2c_write_byte (u8 devaddr, u8 regoffset, u8 value)
 	status = wait_for_pin ();
 
 	if (status & I2C_STAT_XRDY) {
-#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
+#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
+    defined(CONFIG_OMAP44XX)
 		/* send out 1 byte */
 		writeb (regoffset, &i2c_base->data);
 		writew (I2C_STAT_XRDY, &i2c_base->stat);
@@ -274,7 +278,8 @@ static void flush_fifo(void)
 	while(1){
 		stat = readw(&i2c_base->stat);
 		if(stat == I2C_STAT_RRDY){
-#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
+#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
+    defined(CONFIG_OMAP44XX)
 			readb(&i2c_base->data);
 #else
 			readw(&i2c_base->data);
@@ -435,3 +440,9 @@ int i2c_set_bus_num(unsigned int bus)
 
 	return 0;
 }
+
+int i2c_get_bus_num(void)
+{
+	return (int) current_bus;
+}
+
diff --git a/drivers/i2c/omap24xx_i2c.h b/drivers/i2c/omap24xx_i2c.h
new file mode 100644
index 0000000..92a3416
--- /dev/null
+++ b/drivers/i2c/omap24xx_i2c.h
@@ -0,0 +1,166 @@
+/*
+ * (C) Copyright 2004-2010
+ * Texas Instruments, <www.ti.com>
+ *
+ * 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
+ */
+#ifndef _OMAP24XX_I2C_H_
+#define _OMAP24XX_I2C_H_
+
+/* I2C masks */
+
+/* I2C Interrupt Enable Register (I2C_IE): */
+#define I2C_IE_GC_IE	(1 << 5)
+#define I2C_IE_XRDY_IE	(1 << 4) /* Transmit data ready interrupt enable */
+#define I2C_IE_RRDY_IE	(1 << 3) /* Receive data ready interrupt enable */
+#define I2C_IE_ARDY_IE	(1 << 2) /* Register access ready interrupt enable */
+#define I2C_IE_NACK_IE	(1 << 1) /* No acknowledgment interrupt enable */
+#define I2C_IE_AL_IE	(1 << 0) /* Arbitration lost interrupt enable */
+
+/* I2C Status Register (I2C_STAT): */
+
+#define I2C_STAT_SBD	(1 << 15) /* Single byte data */
+#define I2C_STAT_BB	(1 << 12) /* Bus busy */
+#define I2C_STAT_ROVR	(1 << 11) /* Receive overrun */
+#define I2C_STAT_XUDF	(1 << 10) /* Transmit underflow */
+#define I2C_STAT_AAS	(1 << 9)  /* Address as slave */
+#define I2C_STAT_GC	(1 << 5)
+#define I2C_STAT_XRDY	(1 << 4)  /* Transmit data ready */
+#define I2C_STAT_RRDY	(1 << 3)  /* Receive data ready */
+#define I2C_STAT_ARDY	(1 << 2)  /* Register access ready */
+#define I2C_STAT_NACK	(1 << 1)  /* No acknowledgment interrupt enable */
+#define I2C_STAT_AL	(1 << 0)  /* Arbitration lost interrupt enable */
+
+/* I2C Interrupt Code Register (I2C_INTCODE): */
+
+#define I2C_INTCODE_MASK	7
+#define I2C_INTCODE_NONE	0
+#define I2C_INTCODE_AL		1	/* Arbitration lost */
+#define I2C_INTCODE_NAK		2	/* No acknowledgement/general call */
+#define I2C_INTCODE_ARDY	3	/* Register access ready */
+#define I2C_INTCODE_RRDY	4	/* Rcv data ready */
+#define I2C_INTCODE_XRDY	5	/* Xmit data ready */
+
+/* I2C Buffer Configuration Register (I2C_BUF): */
+
+#define I2C_BUF_RDMA_EN		(1 << 15) /* Receive DMA channel enable */
+#define I2C_BUF_XDMA_EN		(1 << 7)  /* Transmit DMA channel enable */
+
+/* I2C Configuration Register (I2C_CON): */
+
+#define I2C_CON_EN	(1 << 15)  /* I2C module enable */
+#define I2C_CON_BE	(1 << 14)  /* Big endian mode */
+#define I2C_CON_STB	(1 << 11)  /* Start byte mode (master mode only) */
+#define I2C_CON_MST	(1 << 10)  /* Master/slave mode */
+#define I2C_CON_TRX	(1 << 9)   /* Transmitter/receiver mode */
+				   /* (master mode only) */
+#define I2C_CON_XA	(1 << 8)   /* Expand address */
+#define I2C_CON_STP	(1 << 1)   /* Stop condition (master mode only) */
+#define I2C_CON_STT	(1 << 0)   /* Start condition (master mode only) */
+
+/* I2C System Test Register (I2C_SYSTEST): */
+
+#define I2C_SYSTEST_ST_EN	(1 << 15) /* System test enable */
+#define I2C_SYSTEST_FREE	(1 << 14) /* Free running mode, on brkpoint) */
+#define I2C_SYSTEST_TMODE_MASK	(3 << 12) /* Test mode select */
+#define I2C_SYSTEST_TMODE_SHIFT	(12)	  /* Test mode select */
+#define I2C_SYSTEST_SCL_I	(1 << 3)  /* SCL line sense input value */
+#define I2C_SYSTEST_SCL_O	(1 << 2)  /* SCL line drive output value */
+#define I2C_SYSTEST_SDA_I	(1 << 1)  /* SDA line sense input value */
+#define I2C_SYSTEST_SDA_O	(1 << 0)  /* SDA line drive output value */
+
+#define I2C_SCLL_SCLL		0
+#define I2C_SCLL_SCLL_M		0xFF
+#define I2C_SCLL_HSSCLL		8
+#define I2C_SCLH_HSSCLL_M	0xFF
+#define I2C_SCLH_SCLH		0
+#define I2C_SCLH_SCLH_M		0xFF
+#define I2C_SCLH_HSSCLH		8
+#define I2C_SCLH_HSSCLH_M	0xFF
+
+#define OMAP_I2C_STANDARD	100000
+#define OMAP_I2C_FAST_MODE	400000
+#define OMAP_I2C_HIGH_SPEED	3400000
+
+#define SYSTEM_CLOCK_12		12000000
+#define SYSTEM_CLOCK_13		13000000
+#define SYSTEM_CLOCK_192	19200000
+#define SYSTEM_CLOCK_96		96000000
+
+/* Use the reference value of 96MHz if not explicitly set by the board */
+#ifndef I2C_IP_CLK
+#define I2C_IP_CLK		SYSTEM_CLOCK_96
+#endif
+
+/*
+ * The reference minimum clock for high speed is 19.2MHz.
+ * The linux 2.6.30 kernel uses this value.
+ * The reference minimum clock for fast mode is 9.6MHz
+ * The reference minimum clock for standard mode is 4MHz
+ * In TRM, the value of 12MHz is used.
+ */
+#ifndef I2C_INTERNAL_SAMPLING_CLK
+#define I2C_INTERNAL_SAMPLING_CLK	19200000
+#endif
+
+/*
+ * The equation for the low and high time is
+ * tlow = scll + scll_trim = (sampling clock * tlow_duty) / speed
+ * thigh = sclh + sclh_trim = (sampling clock * (1 - tlow_duty)) / speed
+ *
+ * If the duty cycle is 50%
+ *
+ * tlow = scll + scll_trim = sampling clock / (2 * speed)
+ * thigh = sclh + sclh_trim = sampling clock / (2 * speed)
+ *
+ * In TRM
+ * scll_trim = 7
+ * sclh_trim = 5
+ *
+ * The linux 2.6.30 kernel uses
+ * scll_trim = 6
+ * sclh_trim = 6
+ *
+ * These are the trim values for standard and fast speed
+ */
+#ifndef I2C_FASTSPEED_SCLL_TRIM
+#define I2C_FASTSPEED_SCLL_TRIM		6
+#endif
+#ifndef I2C_FASTSPEED_SCLH_TRIM
+#define I2C_FASTSPEED_SCLH_TRIM		6
+#endif
+
+/* These are the trim values for high speed */
+#ifndef I2C_HIGHSPEED_PHASE_ONE_SCLL_TRIM
+#define I2C_HIGHSPEED_PHASE_ONE_SCLL_TRIM	I2C_FASTSPEED_SCLL_TRIM
+#endif
+#ifndef I2C_HIGHSPEED_PHASE_ONE_SCLH_TRIM
+#define I2C_HIGHSPEED_PHASE_ONE_SCLH_TRIM	I2C_FASTSPEED_SCLH_TRIM
+#endif
+#ifndef I2C_HIGHSPEED_PHASE_TWO_SCLL_TRIM
+#define I2C_HIGHSPEED_PHASE_TWO_SCLL_TRIM	I2C_FASTSPEED_SCLL_TRIM
+#endif
+#ifndef I2C_HIGHSPEED_PHASE_TWO_SCLH_TRIM
+#define I2C_HIGHSPEED_PHASE_TWO_SCLH_TRIM	I2C_FASTSPEED_SCLH_TRIM
+#endif
+
+#define I2C_PSC_MAX		0x0f
+#define I2C_PSC_MIN		0x00
+
+#endif /* _OMAP24XX_I2C_H_ */