[U-Boot] [PATCH 08/10] ARMV7: Restructure OMAP i2c driver to allow code sharing between OMAP3 and OMAP4
Steve Sakoman
steve at sakoman.com
Tue Jun 15 06:39:49 CEST 2010
This patch modifies the omap24xx driver so that it will also work with OMAP4.
Signed-off-by: Steve Sakoman <steve at sakoman.com>
---
arch/arm/include/asm/arch-omap4/i2c.h | 215 +++++++++++++++++++++++++++++++++
drivers/i2c/omap24xx_i2c.c | 15 ++-
2 files changed, 227 insertions(+), 3 deletions(-)
create mode 100644 arch/arm/include/asm/arch-omap4/i2c.h
diff --git a/arch/arm/include/asm/arch-omap4/i2c.h b/arch/arm/include/asm/arch-omap4/i2c.h
new file mode 100644
index 0000000..e1f578f
--- /dev/null
+++ b/arch/arm/include/asm/arch-omap4/i2c.h
@@ -0,0 +1,215 @@
+/*
+ * (C) Copyright 2004-2008
+ * 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 _I2C_H_
+#define _I2C_H_
+
+#define I2C_DEFAULT_BASE I2C_BASE1
+
+struct i2c {
+ unsigned short revnb_lo; /* 0x00 */
+ unsigned short res1;
+ unsigned short revnb_hi; /* 0x04 */
+ unsigned short res2[13];
+ unsigned short sysc; /* 0x20 */
+ unsigned short res3;
+ unsigned short irqstatus_raw; /* 0x24 */
+ unsigned short res4;
+ unsigned short stat; /* 0x28 */
+ unsigned short res5;
+ unsigned short ie; /* 0x2C */
+ unsigned short res6;
+ unsigned short irqenable_clr; /* 0x30 */
+ unsigned short res7;
+ unsigned short iv; /* 0x34 */
+ unsigned short res8[45];
+ unsigned short syss; /* 0x90 */
+ unsigned short res9;
+ unsigned short buf; /* 0x94 */
+ unsigned short res10;
+ unsigned short cnt; /* 0x98 */
+ unsigned short res11;
+ unsigned short data; /* 0x9C */
+ unsigned short res13;
+ unsigned short res14; /* 0xA0 */
+ unsigned short res15;
+ unsigned short con; /* 0xA4 */
+ unsigned short res16;
+ unsigned short oa; /* 0xA8 */
+ unsigned short res17;
+ unsigned short sa; /* 0xAC */
+ unsigned short res18;
+ unsigned short psc; /* 0xB0 */
+ unsigned short res19;
+ unsigned short scll; /* 0xB4 */
+ unsigned short res20;
+ unsigned short sclh; /* 0xB8 */
+ unsigned short res21;
+ unsigned short systest; /* 0xBC */
+ unsigned short res22;
+ unsigned short bufstat; /* 0xC0 */
+ unsigned short res23;
+};
+
+#define I2C_BUS_MAX 3
+
+/* 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 /* _I2C_H_ */
diff --git a/drivers/i2c/omap24xx_i2c.c b/drivers/i2c/omap24xx_i2c.c
index ff18991..0ff18af 100644
--- a/drivers/i2c/omap24xx_i2c.c
+++ b/drivers/i2c/omap24xx_i2c.c
@@ -176,7 +176,8 @@ 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 +222,8 @@ 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 +276,8 @@ 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 +438,9 @@ int i2c_set_bus_num(unsigned int bus)
return 0;
}
+
+int i2c_get_bus_num(void)
+{
+ return (int) current_bus;
+}
+
--
1.7.0.4
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