[U-Boot] [PATCH 08/10] ARMV7: Restructure OMAP i2c driver to allow code sharing between OMAP3 and OMAP4

[Heiko Schocher <hs@denx.de>]

Hello Steve,

Steve Sakoman wrote:
> This patch modifies the omap24xx driver so that it will also work with OMAP4.
> 
> Signed-off-by: Steve Sakoman <steve@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

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 _I2C_H_
> +#define _I2C_H_

Please use another name, _I2C_H_ is used in include/i2c.h

What with

#define _OMAP4_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 */

This seems identical to me to the defines in

arch/arm/include/asm/arch-omap24xx/i2c.h and
arch/arm/include/asm/arch-omap3/i2c.h

Instead of making here a third copy of this defines, we
should make a common omap i2c.h file, which collects all
common defines, and only add in this file here the
specific defines.

This applies to a lot of defines below. Please
clean up, thanks!

> +
> +/* 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;
> +}
> +

bye,
Heiko
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