[U-Boot] [PATCH 12/13] at91: add hardware i2c drivers

[Heiko Schocher <hs@denx.de>]

Hello Jean,

Jean-Christophe PLAGNIOL-VILLARD wrote:
> Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
> ---
>  cpu/arm926ejs/at91/Makefile                        |    6 +
>  .../arm926ejs/at91/at91cap9_i2c.c                  |   31 ++--
>  .../arm926ejs/at91/at91sam9260_i2c.c               |   31 ++--
>  .../arm926ejs/at91/at91sam9261_i2c.c               |   31 ++--
>  .../arm926ejs/at91/at91sam9263_i2c.c               |   31 ++--
>  .../clk.h => cpu/arm926ejs/at91/at91sam9rl_i2c.c   |   37 ++--
>  drivers/i2c/Makefile                               |    1 +
>  drivers/i2c/atmel_i2c.c                            |  234 ++++++++++++++++++++
>  include/asm-arm/arch-at91/at91_common.h            |    2 +
>  include/asm-arm/arch-at91/at91_twi.h               |   68 ++++++
>  include/asm-arm/arch-at91/clk.h                    |    4 +
>  include/asm-arm/arch-at91/hardware.h               |    5 +
>  12 files changed, 405 insertions(+), 76 deletions(-)
>  copy include/asm-arm/arch-at91/at91_common.h => cpu/arm926ejs/at91/at91cap9_i2c.c (61%)
>  copy include/asm-arm/arch-at91/at91_common.h => cpu/arm926ejs/at91/at91sam9260_i2c.c (61%)
>  copy include/asm-arm/arch-at91/at91_common.h => cpu/arm926ejs/at91/at91sam9261_i2c.c (61%)
>  copy include/asm-arm/arch-at91/at91_common.h => cpu/arm926ejs/at91/at91sam9263_i2c.c (61%)
>  copy include/asm-arm/arch-at91/clk.h => cpu/arm926ejs/at91/at91sam9rl_i2c.c (52%)
>  create mode 100644 drivers/i2c/atmel_i2c.c
>  create mode 100644 include/asm-arm/arch-at91/at91_twi.h
>
>   
[...]
> diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
> index 9c74657..27a5251 100644
> --- a/drivers/i2c/Makefile
> +++ b/drivers/i2c/Makefile
> @@ -25,6 +25,7 @@ include $(TOPDIR)/config.mk
>  
>  LIB	:= $(obj)libi2c.a
>  
> +COBJS-$(CONFIG_I2C_ATMEL) += atmel_i2c.o
>  COBJS-$(CONFIG_BFIN_TWI_I2C) += bfin-twi_i2c.o
>  COBJS-$(CONFIG_FSL_I2C) += fsl_i2c.o
>  COBJS-$(CONFIG_I2C_MXC) += mxc_i2c.o
>   

Independent from your patch, I think we need here a common
rule. Either we name in future this define "CONFIG_I2C_XXX"
or "CONFIG_XXX_I2C. I vote for using "CONFIG_I2C_XXX"

> diff --git a/drivers/i2c/atmel_i2c.c b/drivers/i2c/atmel_i2c.c
> new file mode 100644
> index 0000000..b4c5530
> --- /dev/null
> +++ b/drivers/i2c/atmel_i2c.c
> @@ -0,0 +1,234 @@
> +/*
> + *  i2c Support for Atmel's AT91RM9200 Two-Wire Interface
> + *
> + *  (c) Rick Bronson
> + *
> + *  Borrowed heavily from original work by:
> + *  Copyright (c) 2000 Philip Edelbrock <phil@stimpy.netroedge.com>
> + *
> + *  Modified to work with u-boot by (C) 2004 Gary Jennejohn garyj at denx.de
> + *
> + *  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., 675 Mass Ave, Cambridge, MA 02139, USA.
> + *
> +*/
> +#include <common.h>
> +
> +#ifdef CONFIG_HARD_I2C
>   

Why not "#if defined(CONFIG_I2C_ATMEL)" as in the Makefile?

> +
> +#include <i2c.h>
> +#include <asm/io.h>
>   
[...]
> +	if (alen > 1)
> +		return 1;
> +	/* XXX assume an ATMEL AT24C16 */
> +	if (alen == 1) {
> +#if 0 /* EEPROM code already sets this correctly */
> +		chip |= (addr >> 8) & 0xff;
> +#endif
>   

please remove dead code.

> +		addr = addr & 0xff;
> +	}
> +#endif
> +	return at91_xfer(chip, addr, alen, buffer, len, 1);
> +}
> +
> +int
> +i2c_write(unsigned char chip, unsigned int addr, int alen,
> +	  unsigned char *buffer, int len)
> +{
> +#ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
> +	int i;
> +	unsigned char *buf;
> +
> +	/* we only allow one address byte */
> +	if (alen > 1)
> +		return 1;
> +	/* XXX assume an ATMEL AT24C16 */
> +	if (alen == 1) {
> +		buf = buffer;
> +		/* do single byte writes */
> +		for (i = 0; i < len; i++) {
> +#if 0 /* EEPROM code already sets this correctly */
> +			chip |= (addr >> 8) & 0xff;
> +#endif
>   

here too, please remove dead code.

> +			addr = addr & 0xff;
> +			if (at91_xfer(chip, addr, alen, buf++, 1, 0))
> +				return 1;
> +			addr++;
> +		}
> +		return 0;
>   
[...]
> diff --git a/include/asm-arm/arch-at91/at91_twi.h b/include/asm-arm/arch-at91/at91_twi.h
> new file mode 100644
> index 0000000..bb2880f
> --- /dev/null
> +++ b/include/asm-arm/arch-at91/at91_twi.h
> @@ -0,0 +1,68 @@
> +/*
> + * arch/arm/mach-at91/include/mach/at91_twi.h
> + *
> + * Copyright (C) 2005 Ivan Kokshaysky
> + * Copyright (C) SAN People
> + *
> + * Two-wire Interface (TWI) registers.
> + * Based on AT91RM9200 datasheet revision E.
> + *
> + * 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.
> + */
> +
> +#ifndef AT91_TWI_H
> +#define AT91_TWI_H
> +
> +#define	AT91_TWI_CR		0x00		/* Control Register */
> +#define		AT91_TWI_START		(1 <<  0)	/* Send a Start Condition */
> +#define		AT91_TWI_STOP		(1 <<  1)	/* Send a Stop Condition */
> +#define		AT91_TWI_MSEN		(1 <<  2)	/* Master Transfer Enable */
> +#define		AT91_TWI_MSDIS		(1 <<  3)	/* Master Transfer Disable */
> +#define		AT91_TWI_SVEN		(1 <<  4)	/* Slave Transfer Enable [SAM9260 only] */
> +#define		AT91_TWI_SVDIS		(1 <<  5)	/* Slave Transfer Disable [SAM9260 only] */
> +#define		AT91_TWI_SWRST		(1 <<  7)	/* Software Reset */
>   
                 ^^^^^^^^^^^^^^^
                 doule tabs breaks line length (this affects for the
whole file)

> +
> +#define	AT91_TWI_MMR		0x04		/* Master Mode Register */
> +#define		AT91_TWI_IADRSZ		(3    <<  8)	/* Internal Device Address Size */
> +#define			AT91_TWI_IADRSZ_NO		(0 << 8)
> +#define			AT91_TWI_IADRSZ_1		(1 << 8)
> +#define			AT91_TWI_IADRSZ_2		(2 << 8)
> +#define			AT91_TWI_IADRSZ_3		(3 << 8)
> +#define		AT91_TWI_MREAD		(1    << 12)	/* Master Read Direction */
> +#define		AT91_TWI_DADR		(0x7f << 16)	/* Device Address */
> +
> +#define	AT91_TWI_SMR		0x08		/* Slave Mode Register [SAM9260 only] */
> +#define		AT91_TWI_SADR		(0x7f << 16)	/* Slave Address */
> +
> +#define	AT91_TWI_IADR		0x0c		/* Internal Address Register */
> +
> +#define	AT91_TWI_CWGR		0x10		/* Clock Waveform Generator Register */
> +#define		AT91_TWI_CLDIV		(0xff <<  0)	/* Clock Low Divisor */
> +#define		AT91_TWI_CHDIV		(0xff <<  8)	/* Clock High Divisor */
> +#define		AT91_TWI_CKDIV		(7    << 16)	/* Clock Divider */
> +
> +#define	AT91_TWI_SR		0x20		/* Status Register */
> +#define		AT91_TWI_TXCOMP		(1 <<  0)	/* Transmission Complete */
> +#define		AT91_TWI_RXRDY		(1 <<  1)	/* Receive Holding Register Ready */
> +#define		AT91_TWI_TXRDY		(1 <<  2)	/* Transmit Holding Register Ready */
> +#define		AT91_TWI_SVREAD		(1 <<  3)	/* Slave Read [SAM9260 only] */
> +#define		AT91_TWI_SVACC		(1 <<  4)	/* Slave Access [SAM9260 only] */
> +#define		AT91_TWI_GACC		(1 <<  5)	/* General Call Access [SAM9260 only] */
> +#define		AT91_TWI_OVRE		(1 <<  6)	/* Overrun Error [AT91RM9200 only] */
> +#define		AT91_TWI_UNRE		(1 <<  7)	/* Underrun Error [AT91RM9200 only] */
> +#define		AT91_TWI_NACK		(1 <<  8)	/* Not Acknowledged */
> +#define		AT91_TWI_ARBLST		(1 <<  9)	/* Arbitration Lost [SAM9260 only] */
> +#define		AT91_TWI_SCLWS		(1 << 10)	/* Clock Wait State [SAM9260 only] */
> +#define		AT91_TWI_EOSACC		(1 << 11)	/* End of Slave Address [SAM9260 only] */
> +
> +#define	AT91_TWI_IER		0x24		/* Interrupt Enable Register */
> +#define	AT91_TWI_IDR		0x28		/* Interrupt Disable Register */
> +#define	AT91_TWI_IMR		0x2c		/* Interrupt Mask Register */
> +#define	AT91_TWI_RHR		0x30		/* Receive Holding Register */
> +#define	AT91_TWI_THR		0x34		/* Transmit Holding Register */
> +
> +#endif
> +
>   
bye
Heiko

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