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

Heiko Schocher
2009-03-30T05:53:35Z

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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