[U-Boot] [PATCH 3/4] I2C: add driver of st-ericsson u8500 i2c

Heiko Schocher hs at denx.de
Wed Mar 23 08:00:01 CET 2011


Hello John,

John Rigby wrote:
> From: Michael Brandt <michael.brandt at stericsson.com>
> 
> Signed-off-by: John Rigby <john.rigby at linaro.org>
> ---
>  drivers/i2c/Makefile    |    1 +
>  drivers/i2c/u8500_i2c.c |  603 +++++++++++++++++++++++++++++++++++++++++++++++
>  drivers/i2c/u8500_i2c.h |  220 +++++++++++++++++
>  3 files changed, 824 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/i2c/u8500_i2c.c
>  create mode 100644 drivers/i2c/u8500_i2c.h
> 
> diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
> index 052fe36..ac9c00f 100644
> --- a/drivers/i2c/Makefile
> +++ b/drivers/i2c/Makefile
> @@ -40,6 +40,7 @@ COBJS-$(CONFIG_S3C44B0_I2C) += s3c44b0_i2c.o
>  COBJS-$(CONFIG_SOFT_I2C) += soft_i2c.o
>  COBJS-$(CONFIG_SPEAR_I2C) += spr_i2c.o
>  COBJS-$(CONFIG_TSI108_I2C) += tsi108_i2c.o
> +COBJS-$(CONFIG_DRIVER_U8500_I2C) += u8500_i2c.o

please without "_DRIVER". (you also need to sort lists
alphabetically)

>  COBJS	:= $(COBJS-y)
>  SRCS	:= $(COBJS:.o=.c)
> diff --git a/drivers/i2c/u8500_i2c.c b/drivers/i2c/u8500_i2c.c
> new file mode 100644
> index 0000000..8965100
> --- /dev/null
> +++ b/drivers/i2c/u8500_i2c.c
> @@ -0,0 +1,603 @@
> +/*
> + * Copyright (C) ST-Ericsson SA 2010
> + *
> + * Basic U-Boot I2C interface for STn8500/DB8500
> + * Author: Michael Brandt <Michael.Brandt at stericsson.com> for ST-Ericsson
> + *
> + * 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.
> + */
> +
> +/*
> + * Only 7-bit I2C device addresses are supported.
> + */
> +
> +#include <common.h>
> +#include <i2c.h>
> +
> +#include "u8500_i2c.h"
> +#include <asm/io.h>
> +#include <asm/arch/common.h>
> +#include <asm/arch/clock.h>
> +
> +#define I2C_ENDAD_COUNTER	(CONFIG_SYS_HZ/100)	/* I2C bus timeout */
> +#define I2C_FIFO_FLUSH_COUNTER	500000		/* flush "timeout" */
> +#define I2C_SCL_FREQ		100000		/* I2C bus clock frequency.*/
> +#define I2C_INPUT_FREQ		48000000	/* Input clock frequency.*/
> +#define TX_FIFO_THRESHOLD	0x4
> +#define RX_FIFO_THRESHOLD	0x4
> +#define SLAVE_SETUP_TIME 14 /* Slave data setup time, 250ns for 48MHz i2c_clk */
> +
> +#define WRITE_FIELD(var, mask, shift, value) \
> +			(var = ((var & ~(mask)) | ((value) << (shift))))
> +
> +static unsigned int bus_initialized[CONFIG_SYS_I2C_BUS_MAX];
> +static unsigned int i2c_bus_num;
> +static unsigned int i2c_bus_speed[] = {
> +	CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SPEED,
> +	CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SPEED
> +};

All busses with the same speed? Also please use something
like "CONFIG_SYS_I2C_U8500_SPEED"

> +static struct u8500_i2c_regs *i2c_dev[] = {
> +	(struct u8500_i2c_regs *)CONFIG_SYS_I2C0_BASE,
> +	(struct u8500_i2c_regs *)CONFIG_SYS_I2C1_BASE,
> +	(struct u8500_i2c_regs *)CONFIG_SYS_I2C2_BASE,
> +	(struct u8500_i2c_regs *)CONFIG_SYS_I2C3_BASE,

Could we use for example "CONFIG_SYS_I2C_U8500_BASEx"?

> +};
> +
> +static struct {
> +	int periph;
> +	int pcken;
> +	int kcken;
> +} i2c_clock_bits[] = {
> +	{3, 3, 3}, /* I2C0 */
> +	{1, 2, 2}, /* I2C1 */
> +	{1, 6, 6}, /* I2C2 */
> +	{2, 0, 0}, /* I2C3 */
> +};
[...]
> diff --git a/drivers/i2c/u8500_i2c.h b/drivers/i2c/u8500_i2c.h
> new file mode 100644
> index 0000000..8ef6667
> --- /dev/null
> +++ b/drivers/i2c/u8500_i2c.h
> @@ -0,0 +1,220 @@
> +/*
> + * Copyright (C) ST-Ericsson SA 2009
> + *
> + * 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 _U8500_I2C_H_
> +#define _U8500_I2C_H_
> +
> +#include <asm/types.h>
> +#include <asm/io.h>
> +#include <asm/errno.h>
> +
> +//#include "common.h"

No C99 comments please. If it is dead code, please remove.

> +#include <asm/arch/u8500.h>
> +
> +/* Generic macros */
> +
> +#define I2C_WRITE_FIELD(reg_name, mask, shift, value) \
> +		(reg_name = ((reg_name & ~mask) | (value << shift)))
> +#define I2C_READ_FIELD(reg_name, mask, shift)    ((reg_name & mask) >> shift)
> +
> +struct u8500_i2c_regs {
> +	u32 cr;			/* Control Register                      0x00 */
> +	u32 scr;		/* Slave Address Register                0x04 */
> +	u32 hsmcr;		/* HS Master code Register               0x08 */
> +	u32 mcr;		/* Master Control Register               0x0C */
> +	u32 tfr;		/* Transmit Fifo Register                0x10 */
> +	u32 sr;			/* Status Register                       0x14 */
> +	u32 rfr;		/* Receiver Fifo Register                0x18 */
> +	u32 tftr;		/* Transmit Fifo Threshold Register      0x1C */
> +	u32 rftr;		/* Receiver Fifo Threshold Register      0x20 */
> +	u32 dmar;		/* DMA register                          0x24 */
> +	u32 brcr;		/* Baud Rate Counter Register            0x28 */
> +	u32 imscr;		/* Interrupt Mask Set and Clear Register 0x2C */
> +	u32 risr;		/* Raw interrupt status register         0x30 */
> +	u32 misr;		/* Masked interrupt status register      0x34 */
> +	u32 icr;		/* Interrupt Set and Clear Register      0x38 */
> +	u32 reserved_1[(0xFE0 - 0x3c) >> 2];	/* Reserved 0x03C to 0xFE0 */
> +	u32 periph_id_0;	/* peripheral ID 0	0xFE0 */
> +	u32 periph_id_1;	/* peripheral ID 1	0xFE4 */
> +	u32 periph_id_2;	/* peripheral ID 2	0xFE8 */
> +	u32 periph_id_3;	/* peripheral ID 3	0xFEC */
> +	u32 cell_id_0;		/* I2C cell   ID 0	0xFF0 */
> +	u32 cell_id_1;		/* I2C cell   ID 1	0xFF4 */
> +	u32 cell_id_2;		/* I2C cell   ID 2	0xFF8 */
> +	u32 cell_id_3;		/* I2C cell   ID 3	0xFFC */
> +};
> +
> +
> +/* Control Register */
> +
> +/* Mask values for control register mask */
> +#define I2C_CR_PE          MASK_BIT0	/* Peripheral enable */
> +#define I2C_CR_OM          0x6		/* Operation mode */
> +#define I2C_CR_SAM         MASK_BIT3	/* Slave Addressing mode */
> +#define I2C_CR_SM          0x30		/* Speed mode */
> +#define I2C_CR_SGCM        MASK_BIT6	/* Slave General call mode */
> +#define I2C_CR_FTX         MASK_BIT7	/* Flush Transmit */
> +#define I2C_CR_FRX         MASK_BIT8	/* Flush Receive */
> +#define I2C_CR_DMA_TX_EN   MASK_BIT9	/* DMA TX Enable */
> +#define I2C_CR_DMA_RX_EN   MASK_BIT10	/* DMA Rx Enable */
> +#define I2C_CR_DMA_SLE     MASK_BIT11	/* DMA Synchronization Logic enable */
> +#define I2C_CR_LM          MASK_BIT12	/* Loop back mode */
> +#define I2C_CR_FON         0x6000	/* Filtering On */
> +
> +/* shift valus for control register bit fields */
> +#define I2C_CR_SHIFT_PE		0	/* Peripheral enable */
> +#define I2C_CR_SHIFT_OM		1	/* Operation mode */
> +#define I2C_CR_SHIFT_SAM	3	/* Slave Addressing mode */
> +#define I2C_CR_SHIFT_SM		4	/* Speed mode */
> +#define I2C_CR_SHIFT_SGCM	6	/* Slave General call mode */
> +#define I2C_CR_SHIFT_FTX	7	/* Flush Transmit */
> +#define I2C_CR_SHIFT_FRX	8	/* Flush Receive */
> +#define I2C_CR_SHIFT_DMA_TX_EN	9	/* DMA TX Enable */
> +#define I2C_CR_SHIFT_DMA_RX_EN	10	/* DMA Rx Enable */
> +#define I2C_CR_SHIFT_DMA_SLE	11	/* DMA Synch Logic enable */
> +#define I2C_CR_SHIFT_LM		12	/* Loop back mode */
> +#define I2C_CR_SHIFT_FON	13	/* Filtering On */
> +
> +/* bus operation modes */
> +#define I2C_BUS_SLAVE_MODE		0
> +#define I2C_BUS_MASTER_MODE		1
> +#define I2C_BUS_MASTER_SLAVE_MODE	2
> +
> +
> +/* Slave control register*/
> +
> +/* Mask values slave control register */
> +#define I2C_SCR_ADDR                   0x3FF
> +#define I2C_SCR_DATA_SETUP_TIME        0xFFFF0000
> +
> +/* Shift values for Slave control register */
> +#define I2C_SCR_SHIFT_ADDR               0
> +#define I2C_SCR_SHIFT_DATA_SETUP_TIME    16
> +
> +
> +/* Master Control Register */
> +
> +/* Mask values for Master control register */
> +#define I2C_MCR_OP	MASK_BIT0	/* Operation */
> +#define I2C_MCR_A7	0xFE		/* LSB bits of the Address(7-bit ) */
> +#define I2C_MCR_EA10	0x700		/* Extended Address */
> +#define I2C_MCR_SB	MASK_BIT11	/* Start byte procedure */
> +#define I2C_MCR_AM	0x3000		/* Address type */
> +#define I2C_MCR_STOP	MASK_BIT14	/* stop condition */
> +#define I2C_MCR_LENGTH	0x3FF8000	/* Frame length */
> +#define I2C_MCR_A10	0x7FE		/* Define to set the 10 bit address */
> +/* mask for length field,stop and operation  */
> +#define I2C_MCR_LENGTH_STOP_OP	0x3FFC001
> +
> +/* Shift values for Master control values */
> +#define I2C_MCR_SHIFT_OP	0	/* Operation */
> +#define I2C_MCR_SHIFT_A7	1	/* LSB bits of the Address(7-bit ) */
> +#define I2C_MCR_SHIFT_EA10	8	/* Extended Address */
> +#define I2C_MCR_SHIFT_SB	11	/* Start byte procedure */
> +#define I2C_MCR_SHIFT_AM	12	/* Address type */
> +#define I2C_MCR_SHIFT_STOP	14	/* stop condition */
> +#define I2C_MCR_SHIFT_LENGTH	15	/* Frame length */
> +#define I2C_MCR_SHIFT_A10	1	/* define to set the 10 bit addres */
> +
> +#define I2C_MCR_SHIFT_LENGTH_STOP_OP	0
> +
> +
> +/* Status Register */
> +
> +/* Mask values for Status register */
> +#define I2C_SR_OP		0x3	/* Operation */
> +#define I2C_SR_STATUS		0xC	/* Controller Status */
> +#define I2C_SR_CAUSE		0x70	/* Abort Cause */
> +#define I2C_SR_TYPE		0x180	/* Receive Type */
> +#define I2C_SR_LENGTH		0xFF700	/* Transfer length */
> +
> +/* Shift values for Status register */
> +#define I2C_SR_SHIFT_OP		0	/* Operation */
> +#define I2C_SR_SHIFT_STATUS	2	/* Controller Status */
> +#define I2C_SR_SHIFT_CAUSE	4	/* Abort Cause */
> +#define I2C_SR_SHIFT_TYPE	7	/* Receive Type */
> +#define I2C_SR_SHIFT_LENGTH	9	/* Transfer length */
> +
> +/* abort cause */
> +#define	I2C_NACK_ADDR	0
> +#define	I2C_NACK_DATA	1
> +#define	I2C_ACK_MCODE	2
> +#define	I2C_ARB_LOST	3
> +#define	I2C_BERR_START	4
> +#define	I2C_BERR_STOP	5
> +#define	I2C_OVFL	6
> +
> +
> +/* Baud rate counter registers */
> +
> +/* Mask values for Baud rate counter register */
> +#define I2C_BRCR_BRCNT2	0xFFFF		/* Baud Rate Counter for HS mode */
> +#define I2C_BRCR_BRCNT1	0xFFFF0000	/* counter for Standard and Fast mode */
> +
> +/* Shift values for the Baud rate counter register */
> +#define I2C_BRCR_SHIFT_BRCNT2	0
> +#define I2C_BRCR_SHIFT_BRCNT1	16
> +
> +
> +/* Interrupt Register  */
> +
> +/* Mask values for Interrupt registers */
> +#define I2C_INT_TXFE	MASK_BIT0	/* Tx fifo empty */
> +#define I2C_INT_TXFNE	MASK_BIT1	/* Tx Fifo nearly empty */
> +#define I2C_INT_TXFF	MASK_BIT2	/* Tx Fifo Full */
> +#define I2C_INT_TXFOVR	MASK_BIT3	/* Tx Fifo over run */
> +#define I2C_INT_RXFE	MASK_BIT4	/* Rx Fifo Empty */
> +#define I2C_INT_RXFNF	MASK_BIT5	/* Rx Fifo nearly empty */
> +#define I2C_INT_RXFF	MASK_BIT6	/* Rx Fifo Full  */
> +#define I2C_INT_RFSR	MASK_BIT16	/* Read From slave request */
> +#define I2C_INT_RFSE	MASK_BIT17	/* Read from slave empty */
> +#define I2C_INT_WTSR	MASK_BIT18	/* Write to Slave request */
> +#define I2C_INT_MTD	MASK_BIT19	/* Master Transcation Done*/
> +#define I2C_INT_STD	MASK_BIT20	/* Slave Transaction Done */
> +#define I2C_INT_MAL	MASK_BIT24	/* Master Arbitation Lost */
> +#define I2C_INT_BERR	MASK_BIT25	/* Bus Error */
> +#define I2C_INT_MTDWS	MASK_BIT28	/* Master Transaction Done wo/ Stop */
> +
> +/* Shift values for Interrupt registers */
> +#define I2C_INT_SHIFT_TXFE	0	/* Tx fifo empty */
> +#define I2C_INT_SHIFT_TXFNE	1	/* Tx Fifo nearly empty */
> +#define I2C_INT_SHIFT_TXFF	2	/* Tx Fifo Full */
> +#define I2C_INT_SHIFT_TXFOVR	3	/* Tx Fifo over run */
> +#define I2C_INT_SHIFT_RXFE	4	/* Rx Fifo Empty */
> +#define I2C_INT_SHIFT_RXFNF	5	/* Rx Fifo nearly empty */
> +#define I2C_INT_SHIFT_RXFF	6	/* Rx Fifo Full  */
> +#define I2C_INT_SHIFT_RFSR	16	/* Read From slave request */
> +#define I2C_INT_SHIFT_RFSE	17	/* Read from slave empty */
> +#define I2C_INT_SHIFT_WTSR	18	/* Write to Slave request */
> +#define I2C_INT_SHIFT_MTD	19	/* Master Transcation Done */
> +#define I2C_INT_SHIFT_STD	20	/* Slave Transaction Done */
> +#define I2C_INT_SHIFT_MAL	24	/* Master Arbitation Lost */
> +#define I2C_INT_SHIFT_BERR	25	/* Bus Error */
> +#define I2C_INT_SHIFT_MTDWS	28	/* Master Transcation Done wo/ Stop */
> +
> +
> +/* Misc defines */
> +#define I2C_MAX_STANDARD_SCL	100000	/* Max clock (Hz) for Standard Mode */
> +#define I2C_MAX_FAST_SCL	400000	/* Max clock (Hz) for Fast Mode */
> +#define I2C_MAX_HIGH_SPEED_SCL	3400000	/* Max clock (Hz) for HS Mode */
> +
> +#endif	/* _U8500_I2C_H_ */

Hmm... all your defines use "general" names, there is no "U8500" or
"ST" or something in it. How about prefixing the macros in this file
as U8500_I2C or ST_I2C instead of I2C?

bye,
Heiko
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DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany


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