[U-Boot] [PATCH V2 1/5] pxa: move i2c driver to the common place

Lei Wen adrian.wenl at gmail.com
Thu Mar 17 07:25:14 CET 2011


Hi Heiko,

On Tue, Mar 15, 2011 at 2:48 PM, Heiko Schocher <hs at denx.de> wrote:
> Hello Lei,
>
> Lei Wen wrote:
>> For better sharing with other platform other than pxa's,
>> it is more convenient to put the driver to the common place.
>>
>> Signed-off-by: Lei Wen <leiwen at marvell.com>
>> ---
>> Changelog:
>> v2: rename previous pxa_i2c to mvi2c.
>
> Maybe a Coding Style cleanup would be good for this file ...
> (I know, you don;t wrote this file...)
>
>>  arch/arm/cpu/pxa/Makefile |    1 -
>>  arch/arm/cpu/pxa/i2c.c    |  469 ---------------------------------------------
>>  drivers/i2c/Makefile      |    1 +
>>  drivers/i2c/mvi2c.c       |  469 +++++++++++++++++++++++++++++++++++++++++++++
>
> Why you don;t use git format-patch -M ?
> If so, I wouldn;t stumbled over the Coding Style ;-)
>
>>  include/configs/innokom.h |    1 +
>>  include/configs/xm250.h   |    1 +
>>  6 files changed, 472 insertions(+), 470 deletions(-)
>>  delete mode 100644 arch/arm/cpu/pxa/i2c.c
>>  create mode 100644 drivers/i2c/mvi2c.c
>>
> [...]
>> diff --git a/drivers/i2c/mvi2c.c b/drivers/i2c/mvi2c.c
>> new file mode 100644
>> index 0000000..7aa49ae
>> --- /dev/null
>> +++ b/drivers/i2c/mvi2c.c
>> @@ -0,0 +1,469 @@
>> +/*
>> + * (C) Copyright 2000
>> + * Paolo Scaffardi, AIRVENT SAM s.p.a - RIMINI(ITALY), arsenio at tin.it
>> + *
>> + * (C) Copyright 2000 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
>> + * Marius Groeger <mgroeger at sysgo.de>
>> + *
>> + * (C) Copyright 2003 Pengutronix e.K.
>> + * Robert Schwebel <r.schwebel at pengutronix.de>
>> + *
>> + * 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
>> + *
>> + * Back ported to the 8xx platform (from the 8260 platform) by
>> + * Murray.Jensen at cmst.csiro.au, 27-Jan-01.
>> + */
>> +
>> +/* FIXME: this file is PXA255 specific! What about other XScales? */
>
> As you rename this file to mv, please change this comment.
>
>> +
>> +#include <common.h>
>> +#include <asm/io.h>
>> +
>> +#ifdef CONFIG_HARD_I2C
>> +
>> +/*
>> + *   - CONFIG_SYS_I2C_SPEED
>> + *   - I2C_PXA_SLAVE_ADDR
>> + */
>> +
>> +#include <asm/arch/hardware.h>
>> +#include <asm/arch/pxa-regs.h>
>> +#include <i2c.h>
>> +
>> +/*#define    DEBUG_I2C       1       /###* activate local debugging output  */
>
> Please remove dead code.
>
>> +#define I2C_PXA_SLAVE_ADDR   0x1     /* slave pxa unit address           */
>> +
>> +#if (CONFIG_SYS_I2C_SPEED == 400000)
>> +#define I2C_ICR_INIT (ICR_FM | ICR_BEIE | ICR_IRFIE | ICR_ITEIE | ICR_GCD | ICR_SCLE)
>
> Line too long.
>
>> +#else
>> +#define I2C_ICR_INIT (ICR_BEIE | ICR_IRFIE | ICR_ITEIE | ICR_GCD | ICR_SCLE)
>> +#endif
>> +
>> +#define I2C_ISR_INIT         0x7FF
>> +
>> +#ifdef DEBUG_I2C
>> +#define PRINTD(x) printf x
>> +#else
>> +#define PRINTD(x)
>> +#endif
>> +
>> +
>> +/* Shall the current transfer have a start/stop condition? */
>> +#define I2C_COND_NORMAL              0
>> +#define I2C_COND_START               1
>> +#define I2C_COND_STOP                2
>> +
>> +/* Shall the current transfer be ack/nacked or being waited for it? */
>> +#define I2C_ACKNAK_WAITACK   1
>> +#define I2C_ACKNAK_SENDACK   2
>> +#define I2C_ACKNAK_SENDNAK   4
>> +
>> +/* Specify who shall transfer the data (master or slave) */
>> +#define I2C_READ             0
>> +#define I2C_WRITE            1
>> +
>> +/* All transfers are described by this data structure */
>> +struct i2c_msg {
>> +     u8 condition;
>> +     u8 acknack;
>> +     u8 direction;
>> +     u8 data;
>> +};
>> +
>> +
>
> Only one empty line.
>
>> +/**
>> + * i2c_pxa_reset: - reset the host controller
>> + *
>> + */
>
> Wrong comment style, no empty line after the comment necessary.
> Fix globally please.
>
>> +
>> +static void i2c_reset( void )
>
> No spaces after "(" and before ")"
> Fix globally please.
>
>> +{
>> +     writel(readl(ICR) & ~ICR_IUE, ICR);     /* disable unit */
>> +     writel(readl(ICR) | ICR_UR, ICR);       /* reset the unit */
>> +     udelay(100);
>> +     writel(readl(ICR) & ~ICR_IUE, ICR);     /* disable unit */
>> +#ifdef CONFIG_CPU_MONAHANS
>> +     /* | CKENB_1_PWM1 | CKENB_0_PWM0); */
>> +     writel(readl(CKENB) | (CKENB_4_I2C), CKENB);
>> +#else /* CONFIG_CPU_MONAHANS */
>> +     /* set the global I2C clock on */
>> +     writel(readl(CKEN) | CKEN14_I2C, CKEN);
>> +#endif
>> +     writel(I2C_PXA_SLAVE_ADDR, ISAR);       /* set our slave address */
>> +     writel(I2C_ICR_INIT, ICR);              /* set control reg values */
>> +     writel(I2C_ISR_INIT, ISR);              /* set clear interrupt bits */
>> +     writel(readl(ICR) | ICR_IUE, ICR);      /* enable unit */
>> +     udelay(100);
>> +}
>> +
>> +
>> +/**
>> + * i2c_isr_set_cleared: - wait until certain bits of the I2C status register
>> + *                     are set and cleared
>> + *
>> + * @return: 1 in case of success, 0 means timeout (no match within 10 ms).
>> + */
>> +static int i2c_isr_set_cleared( unsigned long set_mask, unsigned long cleared_mask )
>
> Line too long.
>
>> +{
>> +     int timeout = 10000;
>> +
>> +     while( ((ISR & set_mask)!=set_mask) || ((ISR & cleared_mask)!=0) ){
>              ^                 ^                                         ^
>              no space          space around "!="                         space
>
>> +             udelay( 10 );
>> +             if( timeout-- < 0 ) return 0;
>
> return please in a new line, please fix globally.
>
>> +     }
>> +
>> +     return 1;
>> +}
>> +
>> +
>> +/**
>> + * i2c_transfer: - Transfer one byte over the i2c bus
>> + *
>> + * This function can tranfer a byte over the i2c bus in both directions.
>> + * It is used by the public API functions.
>> + *
>> + * @return:  0: transfer successful
>> + *          -1: message is empty
>> + *          -2: transmit timeout
>> + *          -3: ACK missing
>> + *          -4: receive timeout
>> + *          -5: illegal parameters
>> + *          -6: bus is busy and couldn't be aquired
>> + */
>> +int i2c_transfer(struct i2c_msg *msg)
>> +{
>> +     int ret;
>> +
>> +     if (!msg)
>> +             goto transfer_error_msg_empty;
>> +
>> +     switch(msg->direction) {
>> +
>
> no empty line please.
>
>> +     case I2C_WRITE:
>> +
>> +             /* check if bus is not busy */
>> +             if (!i2c_isr_set_cleared(0,ISR_IBB))
>                                           ^
>                                           add a space please
>> +                     goto transfer_error_bus_busy;
>> +
>> +             /* start transmission */
>> +             writel(readl(ICR) & ~ICR_START, ICR);
>> +             writel(readl(ICR) & ~ICR_STOP, ICR);
>> +             writel(msg->data, IDBR);
>> +             if (msg->condition == I2C_COND_START)
>> +                     writel(readl(ICR) | ICR_START, ICR);
>> +             if (msg->condition == I2C_COND_STOP)
>> +                     writel(readl(ICR) | ICR_STOP, ICR);
>> +             if (msg->acknack == I2C_ACKNAK_SENDNAK)
>> +                     writel(readl(ICR) | ICR_ACKNAK, ICR);
>> +             if (msg->acknack == I2C_ACKNAK_SENDACK)
>> +                     writel(readl(ICR) & ~ICR_ACKNAK, ICR);
>> +             writel(readl(ICR) & ~ICR_ALDIE, ICR);
>> +             writel(readl(ICR) | ICR_TB, ICR);
>> +
>> +             /* transmit register empty? */
>> +             if (!i2c_isr_set_cleared(ISR_ITE,0))
>                                                 ^
>                                                 here too, fix
>                                                 globally please.
>
>> +                     goto transfer_error_transmit_timeout;
>> +
>> +             /* clear 'transmit empty' state */
>> +             writel(readl(ISR) | ISR_ITE, ISR);
>> +
>> +             /* wait for ACK from slave */
>> +             if (msg->acknack == I2C_ACKNAK_WAITACK)
>> +                     if (!i2c_isr_set_cleared(0,ISR_ACKNAK))
>> +                             goto transfer_error_ack_missing;
>> +             break;
>> +
>> +     case I2C_READ:
>> +
>> +             /* check if bus is not busy */
>> +             if (!i2c_isr_set_cleared(0,ISR_IBB))
>> +                     goto transfer_error_bus_busy;
>> +
>> +             /* start receive */
>> +             writel(readl(ICR) & ~ICR_START, ICR);
>> +             writel(readl(ICR) & ~ICR_STOP, ICR);
>> +             if (msg->condition == I2C_COND_START)
>> +                     writel(readl(ICR) | ICR_START, ICR);
>> +             if (msg->condition == I2C_COND_STOP)
>> +                     writel(readl(ICR) | ICR_STOP, ICR);
>> +             if (msg->acknack == I2C_ACKNAK_SENDNAK)
>> +                     writel(readl(ICR) | ICR_ACKNAK, ICR);
>> +             if (msg->acknack == I2C_ACKNAK_SENDACK)
>> +                     writel(readl(ICR) & ~ICR_ACKNAK, ICR);
>> +             writel(readl(ICR) & ~ICR_ALDIE, ICR);
>> +             writel(readl(ICR) | ICR_TB, ICR);
>> +
>> +             /* receive register full? */
>> +             if (!i2c_isr_set_cleared(ISR_IRF,0))
>> +                     goto transfer_error_receive_timeout;
>> +
>> +             msg->data = readl(IDBR);
>> +
>> +             /* clear 'receive empty' state */
>> +             writel(readl(ISR) | ISR_IRF, ISR);
>> +
>> +             break;
>> +
>> +     default:
>> +
>> +             goto transfer_error_illegal_param;
>> +
>> +     }
>> +
>> +     return 0;
>> +
>> +transfer_error_msg_empty:
>> +             PRINTD(("i2c_transfer: error: 'msg' is empty\n"));
>> +             ret = -1; goto i2c_transfer_finish;
>> +
>> +transfer_error_transmit_timeout:
>> +             PRINTD(("i2c_transfer: error: transmit timeout\n"));
>> +             ret = -2; goto i2c_transfer_finish;
>> +
>> +transfer_error_ack_missing:
>> +             PRINTD(("i2c_transfer: error: ACK missing\n"));
>> +             ret = -3; goto i2c_transfer_finish;
>> +
>> +transfer_error_receive_timeout:
>> +             PRINTD(("i2c_transfer: error: receive timeout\n"));
>> +             ret = -4; goto i2c_transfer_finish;
>> +
>> +transfer_error_illegal_param:
>> +             PRINTD(("i2c_transfer: error: illegal parameters\n"));
>> +             ret = -5; goto i2c_transfer_finish;
>> +
>> +transfer_error_bus_busy:
>> +             PRINTD(("i2c_transfer: error: bus is busy\n"));
>> +             ret = -6; goto i2c_transfer_finish;
>> +
>> +i2c_transfer_finish:
>> +             PRINTD(("i2c_transfer: ISR: 0x%04x\n",ISR));
>> +             i2c_reset();
>> +             return ret;
>> +
>> +}
>> +
>> +/* ------------------------------------------------------------------------ */
>> +/* API Functions                                                            */
>> +/* ------------------------------------------------------------------------ */
>> +
>> +void i2c_init(int speed, int slaveaddr)
>> +{
>> +#ifdef CONFIG_SYS_I2C_INIT_BOARD
>> +     /* call board specific i2c bus reset routine before accessing the   */
>> +     /* environment, which might be in a chip on that bus. For details   */
>> +     /* about this problem see doc/I2C_Edge_Conditions.                  */
>> +     i2c_init_board();
>> +#endif
>> +}
>> +
>> +
>> +/**
>> + * i2c_probe: - Test if a chip answers for a given i2c address
>> + *
>> + * @chip:    address of the chip which is searched for
>> + * @return:  0 if a chip was found, -1 otherwhise
>> + */
>> +
>> +int i2c_probe(uchar chip)
>> +{
>> +     struct i2c_msg msg;
>> +
>> +     i2c_reset();
>> +
>> +     msg.condition = I2C_COND_START;
>> +     msg.acknack   = I2C_ACKNAK_WAITACK;
>> +     msg.direction = I2C_WRITE;
>> +     msg.data      = (chip << 1) + 1;
>> +     if (i2c_transfer(&msg)) return -1;
>> +
>> +     msg.condition = I2C_COND_STOP;
>> +     msg.acknack   = I2C_ACKNAK_SENDNAK;
>> +     msg.direction = I2C_READ;
>> +     msg.data      = 0x00;
>> +     if (i2c_transfer(&msg)) return -1;
>> +
>> +     return 0;
>> +}
>> +
>> +
>> +/**
>> + * i2c_read: - Read multiple bytes from an i2c device
>> + *
>> + * The higher level routines take into account that this function is only
>> + * called with len < page length of the device (see configuration file)
>> + *
>> + * @chip:    address of the chip which is to be read
>> + * @addr:    i2c data address within the chip
>> + * @alen:    length of the i2c data address (1..2 bytes)
>> + * @buffer:  where to write the data
>> + * @len:     how much byte do we want to read
>> + * @return:  0 in case of success
>> + */
>> +
>> +int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
>> +{
>> +     struct i2c_msg msg;
>> +     u8 addr_bytes[3]; /* lowest...highest byte of data address */
>> +     int ret;
>> +
>> +     PRINTD(("i2c_read(chip=0x%02x, addr=0x%02x, alen=0x%02x, len=0x%02x)\n",chip,addr,alen,len));
>
> Line too long, add space after ","
>
>> +
>> +     i2c_reset();
>> +
>> +     /* dummy chip address write */
>> +     PRINTD(("i2c_read: dummy chip address write\n"));
>> +     msg.condition = I2C_COND_START;
>> +     msg.acknack   = I2C_ACKNAK_WAITACK;
>> +     msg.direction = I2C_WRITE;
>> +     msg.data      = (chip << 1);
>> +     msg.data     &= 0xFE;
>> +     if ((ret=i2c_transfer(&msg))) return -1;
>
> Please move the ret = i2c_transfer out of the if condition
> "return -1" please in a new line.
>
>> +
>> +     /*
>> +      * send memory address bytes;
>> +      * alen defines how much bytes we have to send.
>> +      */
>> +     /*addr &= ((1 << CONFIG_SYS_EEPROM_PAGE_WRITE_BITS)-1); */
>> +     addr_bytes[0] = (u8)((addr >>  0) & 0x000000FF);
>> +     addr_bytes[1] = (u8)((addr >>  8) & 0x000000FF);
>> +     addr_bytes[2] = (u8)((addr >> 16) & 0x000000FF);
>> +
>> +     while (--alen >= 0) {
>> +
>> +             PRINTD(("i2c_read: send memory word address byte %1d\n",alen));
>> +             msg.condition = I2C_COND_NORMAL;
>> +             msg.acknack   = I2C_ACKNAK_WAITACK;
>> +             msg.direction = I2C_WRITE;
>> +             msg.data      = addr_bytes[alen];
>> +             if ((ret=i2c_transfer(&msg))) return -1;
>> +     }
>> +
>> +
>> +     /* start read sequence */
>> +     PRINTD(("i2c_read: start read sequence\n"));
>> +     msg.condition = I2C_COND_START;
>> +     msg.acknack   = I2C_ACKNAK_WAITACK;
>> +     msg.direction = I2C_WRITE;
>> +     msg.data      = (chip << 1);
>> +     msg.data     |= 0x01;
>> +     if ((ret=i2c_transfer(&msg))) return -1;
>> +
>> +     /* read bytes; send NACK at last byte */
>> +     while (len--) {
>> +
>> +             if (len==0) {
>> +                     msg.condition = I2C_COND_STOP;
>> +                     msg.acknack   = I2C_ACKNAK_SENDNAK;
>> +             } else {
>> +                     msg.condition = I2C_COND_NORMAL;
>> +                     msg.acknack   = I2C_ACKNAK_SENDACK;
>> +             }
>> +
>> +             msg.direction = I2C_READ;
>> +             msg.data      = 0x00;
>> +             if ((ret=i2c_transfer(&msg))) return -1;
>> +
>> +             *buffer = msg.data;
>> +             PRINTD(("i2c_read: reading byte (0x%08x)=0x%02x\n",(unsigned int)buffer,*buffer));
>> +             buffer++;
>> +
>> +     }
>> +
>> +     i2c_reset();
>> +
>> +     return 0;
>> +}
>> +
>> +
>> +/**
>> + * i2c_write: -  Write multiple bytes to an i2c device
>> + *
>> + * The higher level routines take into account that this function is only
>> + * called with len < page length of the device (see configuration file)
>> + *
>> + * @chip:    address of the chip which is to be written
>> + * @addr:    i2c data address within the chip
>> + * @alen:    length of the i2c data address (1..2 bytes)
>> + * @buffer:  where to find the data to be written
>> + * @len:     how much byte do we want to read
>> + * @return:  0 in case of success
>> + */
>> +
>> +int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
>> +{
>> +     struct i2c_msg msg;
>> +     u8 addr_bytes[3]; /* lowest...highest byte of data address */
>> +
>> +     PRINTD(("i2c_write(chip=0x%02x, addr=0x%02x, alen=0x%02x, len=0x%02x)\n",chip,addr,alen,len));
>> +
>> +     i2c_reset();
>> +
>> +     /* chip address write */
>> +     PRINTD(("i2c_write: chip address write\n"));
>> +     msg.condition = I2C_COND_START;
>> +     msg.acknack   = I2C_ACKNAK_WAITACK;
>> +     msg.direction = I2C_WRITE;
>> +     msg.data      = (chip << 1);
>> +     msg.data     &= 0xFE;
>> +     if (i2c_transfer(&msg)) return -1;
>> +
>> +     /*
>> +      * send memory address bytes;
>> +      * alen defines how much bytes we have to send.
>> +      */
>> +     addr_bytes[0] = (u8)((addr >>  0) & 0x000000FF);
>> +     addr_bytes[1] = (u8)((addr >>  8) & 0x000000FF);
>> +     addr_bytes[2] = (u8)((addr >> 16) & 0x000000FF);
>> +
>> +     while (--alen >= 0) {
>> +
>> +             PRINTD(("i2c_write: send memory word address\n"));
>> +             msg.condition = I2C_COND_NORMAL;
>> +             msg.acknack   = I2C_ACKNAK_WAITACK;
>> +             msg.direction = I2C_WRITE;
>> +             msg.data      = addr_bytes[alen];
>> +             if (i2c_transfer(&msg)) return -1;
>> +     }
>> +
>> +     /* write bytes; send NACK at last byte */
>> +     while (len--) {
>> +
>> +             PRINTD(("i2c_write: writing byte (0x%08x)=0x%02x\n",(unsigned int)buffer,*buffer));
>> +
>> +             if (len==0)
>> +                     msg.condition = I2C_COND_STOP;
>> +             else
>> +                     msg.condition = I2C_COND_NORMAL;
>> +
>> +             msg.acknack   = I2C_ACKNAK_WAITACK;
>> +             msg.direction = I2C_WRITE;
>> +             msg.data      = *(buffer++);
>> +
>> +             if (i2c_transfer(&msg)) return -1;
>> +
>> +     }
>> +
>> +     i2c_reset();
>> +
>> +     return 0;
>> +
>> +}
>> +
>> +#endif       /* CONFIG_HARD_I2C */
>> diff --git a/include/configs/innokom.h b/include/configs/innokom.h
>> index d8fcbdb..0ea73c9 100644
>> --- a/include/configs/innokom.h
>> +++ b/include/configs/innokom.h
>> @@ -140,6 +140,7 @@
>>  /*
>>   * I2C bus
>>   */
>> +#define CONFIG_I2C_MV                        1
>>  #define CONFIG_HARD_I2C                      1
>>  #define CONFIG_SYS_I2C_SPEED                 50000
>>  #define CONFIG_SYS_I2C_SLAVE                 0xfe
>> diff --git a/include/configs/xm250.h b/include/configs/xm250.h
>> index 497cb91..b4b940a 100644
>> --- a/include/configs/xm250.h
>> +++ b/include/configs/xm250.h
>> @@ -61,6 +61,7 @@
>>  /*
>>   * I2C bus
>>   */
>> +#define CONFIG_I2C_MV                        1
>>  #define CONFIG_HARD_I2C                      1
>>  #define CONFIG_SYS_I2C_SPEED                 50000
>>  #define CONFIG_SYS_I2C_SLAVE                 0xfe
>

Thanks for reviewing, I would post the V3 patch to fix the code style issue...

Best regards,
Lei


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