[U-Boot] [PATCHv4 3/4] I2C: Add driver for ST-Ericsson U8500 i2c

John Rigby john.rigby at linaro.org
Thu Apr 28 20:52:35 CEST 2011


On Tue, Apr 19, 2011 at 2:42 PM, John Rigby <john.rigby at linaro.org> wrote:
> From: Michael Brandt <michael.brandt at stericsson.com>
>
> Signed-off-by: John Rigby <john.rigby at linaro.org>
> CC: Heiko Schocher <hs at denx.de>
> ---
> v2: Incorporate suggestions from Heiko Schocher
> v3: Fix line length problem reported by Heiko Schocher
> v4: No changes just rebased to latest and included for completeness
>  drivers/i2c/Makefile    |    1 +
>  drivers/i2c/u8500_i2c.c |  613 +++++++++++++++++++++++++++++++++++++++++++++++
>  drivers/i2c/u8500_i2c.h |  194 +++++++++++++++
>  3 files changed, 808 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..43507fc 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_U8500_I2C) += u8500_i2c.o
>
>  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..ea8a71d
> --- /dev/null
> +++ b/drivers/i2c/u8500_i2c.c
> @@ -0,0 +1,613 @@
> +/*
> + * 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/clock.h>
> +
> +#define U8500_I2C_ENDAD_COUNTER        (CONFIG_SYS_HZ/100)     /* I2C bus timeout */
> +#define U8500_I2C_FIFO_FLUSH_COUNTER   500000          /* flush "timeout" */
> +#define U8500_I2C_SCL_FREQ             100000          /* I2C bus clock freq */
> +#define U8500_I2C_INPUT_FREQ           48000000        /* Input clock freq */
> +#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_U8500_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
> +};
> +static struct u8500_i2c_regs *i2c_dev[] = {
> +       (struct u8500_i2c_regs *)CONFIG_SYS_U8500_I2C0_BASE,
> +       (struct u8500_i2c_regs *)CONFIG_SYS_U8500_I2C1_BASE,
> +       (struct u8500_i2c_regs *)CONFIG_SYS_U8500_I2C2_BASE,
> +       (struct u8500_i2c_regs *)CONFIG_SYS_U8500_I2C3_BASE,
> +};
> +
> +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 */
> +};
> +
> +static void i2c_set_bit(void *reg, u32 mask)
> +{
> +       writel(readl(reg) | mask, reg);
> +}
> +
> +static void i2c_clr_bit(void *reg, u32 mask)
> +{
> +       writel(readl(reg) & ~mask, reg);
> +}
> +
> +static void i2c_write_field(void *reg, u32 mask, uint shift, u32 value)
> +{
> +       writel((readl(reg) & ~mask) | (value << shift), reg);
> +}
> +
> +static int __i2c_set_bus_speed(unsigned int speed)
> +{
> +       u32 value;
> +       struct u8500_i2c_regs *i2c_regs;
> +
> +       i2c_regs = i2c_dev[i2c_bus_num];
> +
> +       /* Select standard (100 kbps) speed mode */
> +       i2c_write_field(&i2c_regs->cr, U8500_I2C_CR_SM,
> +                       U8500_I2C_CR_SHIFT_SM, 0x0);
> +
> +       /*
> +        * Set the Baud Rate Counter 2 value
> +        * Baud rate (standard) = fi2cclk / ( (BRCNT2 x 2) + Foncycle )
> +        * Foncycle = 0 (no digital filtering)
> +        */
> +       value = (u32) (U8500_I2C_INPUT_FREQ / (speed * 2));
> +       i2c_write_field(&i2c_regs->brcr, U8500_I2C_BRCR_BRCNT2,
> +                       U8500_I2C_BRCR_SHIFT_BRCNT2, value);
> +
> +       /* ensure that BRCNT value is zero */
> +       i2c_write_field(&i2c_regs->brcr, U8500_I2C_BRCR_BRCNT1,
> +                       U8500_I2C_BRCR_SHIFT_BRCNT1, 0);
> +
> +       return U8500_I2C_INPUT_FREQ/(value * 2);
> +}
> +
> +/*
> + * i2c_init - initialize the i2c bus
> + *
> + *     speed: bus speed (in HZ)
> + *     slaveaddr: address of device in slave mode
> + *
> + *     Slave mode is not implemented.
> + */
> +void i2c_init(int speed, int slaveaddr)
> +{
> +       struct u8500_i2c_regs *i2c_regs;
> +
> +       debug("i2c_init bus %d, speed %d\n", i2c_bus_num, speed);
> +
> +       u8500_clock_enable(i2c_clock_bits[i2c_bus_num].periph,
> +                          i2c_clock_bits[i2c_bus_num].pcken,
> +                          i2c_clock_bits[i2c_bus_num].kcken);
> +
> +       i2c_regs = i2c_dev[i2c_bus_num];
> +
> +       /* Disable the controller */
> +       i2c_clr_bit(&i2c_regs->cr, U8500_I2C_CR_PE);
> +
> +       /* Clear registers */
> +       writel(0, &i2c_regs->cr);
> +       writel(0, &i2c_regs->scr);
> +       writel(0, &i2c_regs->hsmcr);
> +       writel(0, &i2c_regs->tftr);
> +       writel(0, &i2c_regs->rftr);
> +       writel(0, &i2c_regs->dmar);
> +
> +       i2c_bus_speed[i2c_bus_num] = __i2c_set_bus_speed(speed);
> +
> +       /*
> +        * Set our own address.
> +        * Set slave address mode to 7 bit addressing mode
> +        */
> +       i2c_clr_bit(&i2c_regs->cr, U8500_I2C_CR_SAM);
> +       i2c_write_field(&i2c_regs->scr, U8500_I2C_SCR_ADDR,
> +                       U8500_I2C_SCR_SHIFT_ADDR, slaveaddr);
> +       /* Slave Data Set up Time */
> +       i2c_write_field(&i2c_regs->scr, U8500_I2C_SCR_DATA_SETUP_TIME,
> +                       U8500_I2C_SCR_SHIFT_DATA_SETUP_TIME, SLAVE_SETUP_TIME);
> +
> +       /* Disable the DMA sync logic */
> +       i2c_write_field(&i2c_regs->cr, U8500_I2C_CR_DMA_SLE,
> +                       U8500_I2C_CR_SHIFT_DMA_SLE, 0);
> +
> +       /* Disable interrupts */
> +       writel(0, &i2c_regs->imscr);
> +
> +       /* Configure bus master mode */
> +       i2c_write_field(&i2c_regs->cr, U8500_I2C_CR_OM, U8500_I2C_CR_SHIFT_OM,
> +                       U8500_I2C_BUS_MASTER_MODE);
> +       /* Set FIFO threshold values */
> +       writel(TX_FIFO_THRESHOLD, &i2c_regs->tftr);
> +       writel(RX_FIFO_THRESHOLD, &i2c_regs->rftr);
> +
> +       /* Enable the I2C Controller */
> +       i2c_set_bit(&i2c_regs->cr, U8500_I2C_CR_PE);
> +
> +       bus_initialized[i2c_bus_num] = 1;
> +}
> +
> +
> +/*
> + * loop_till_bit_clear - polls on a bit till it clears
> + * ioreg: register where you want to check status
> + * mask: bit mask for the bit you wish to check
> + * timeout: timeout in ticks/s
> + */
> +static int loop_till_bit_clear(void *io_reg, u32 mask, unsigned long timeout)
> +{
> +       unsigned long timebase = get_timer(0);
> +
> +       do {
> +               if ((readl(io_reg) & mask) == 0x0UL)
> +                       return 0;
> +       } while (get_timer(timebase) < timeout);
> +
> +       debug("loop_till_bit_clear timed out\n");
> +       return -1;
> +}
> +
> +/*
> + * loop_till_bit_set - polls on a bit till it is set.
> + * ioreg: register where you want to check status
> + * mask: bit mask for the bit you wish to check
> + * timeout: timeout in ticks/s
> + */
> +static int loop_till_bit_set(void *io_reg, u32 mask, unsigned long timeout)
> +{
> +       unsigned long timebase = get_timer(0);
> +
> +       do {
> +               if ((readl(io_reg) & mask) != 0x0UL)
> +                       return 0;
> +       } while (get_timer(timebase) < timeout);
> +
> +       debug("loop_till_bit_set timed out\n");
> +       return -1;
> +}
> +
> +/*
> + * flush_fifo - flush the I2C TX and RX FIFOs
> + */
> +static void flush_fifo(struct u8500_i2c_regs *i2c_regs)
> +{
> +       int counter = U8500_I2C_FIFO_FLUSH_COUNTER;
> +
> +       /* Flush Tx FIFO */
> +       i2c_set_bit(&i2c_regs->cr, U8500_I2C_CR_FTX);
> +       /* Flush Rx FIFO */
> +       i2c_set_bit(&i2c_regs->cr, U8500_I2C_CR_FRX);
> +       while (counter--) {
> +               if (!(readl(&i2c_regs->cr) &
> +                               (U8500_I2C_CR_FTX | U8500_I2C_CR_FRX)))
> +                       break;
> +       }
> +       return;
> +}
> +
> +#ifdef DEBUG
> +static void print_abort_reason(struct u8500_i2c_regs *i2c_regs)
> +{
> +       int cause;
> +
> +       printf("abort: risr %08x, sr %08x\n", i2c_regs->risr, i2c_regs->sr);
> +       cause = (readl(&i2c_regs->sr) & U8500_I2C_SR_CAUSE) >>
> +                               U8500_I2C_SR_SHIFT_CAUSE;
> +       switch (cause) {
> +       case U8500_I2C_NACK_ADDR:
> +               printf("No Ack received after Slave Address xmission\n");
> +               break;
> +       case U8500_I2C_NACK_DATA:
> +               printf("Valid for MASTER_WRITE: No Ack received "
> +                               "during data phase\n");
> +               break;
> +       case U8500_I2C_ACK_MCODE:
> +               printf("Master recv ack after xmission of master code"
> +                               "in hs mode\n");
> +               break;
> +       case U8500_I2C_ARB_LOST:
> +               printf("Master Lost arbitration\n");
> +               break;
> +       case U8500_I2C_BERR_START:
> +               printf("Slave restarts\n");
> +               break;
> +       case U8500_I2C_BERR_STOP:
> +               printf("Slave reset\n");
> +               break;
> +       case U8500_I2C_OVFL:
> +               printf("Overflow\n");
> +               break;
> +       default:
> +               printf("Unknown error type\n");
> +       }
> +}
> +#endif
> +
> +/*
> + * i2c_abort - called when a I2C transaction failed
> + */
> +static void i2c_abort(struct u8500_i2c_regs *i2c_regs)
> +{
> +#ifdef DEBUG
> +       print_abort_reason(i2c_regs);
> +#endif
> +       /* flush RX and TX fifos */
> +       flush_fifo(i2c_regs);
> +
> +       /* Acknowledge the Master Transaction Done */
> +       i2c_set_bit(&i2c_regs->icr, U8500_I2C_INT_MTD);
> +
> +       /* Acknowledge the Master Transaction Done Without Stop */
> +       i2c_set_bit(&i2c_regs->icr, U8500_I2C_INT_MTDWS);
> +
> +       i2c_init(i2c_bus_speed[i2c_bus_num], CONFIG_SYS_I2C_SLAVE);
> +}
> +
> +/*
> + * write addr, alias index, to I2C bus.
> + */
> +static int i2c_write_addr(struct u8500_i2c_regs *i2c_regs, uint addr, int alen)
> +{
> +       while (alen--) {
> +               /* Wait until the Tx Fifo is not full */
> +               if (loop_till_bit_clear((void *)&i2c_regs->risr,
> +                                       U8500_I2C_INT_TXFF,
> +                                       U8500_I2C_ENDAD_COUNTER)) {
> +                       i2c_abort(i2c_regs);
> +                       return -1;
> +               }
> +
> +               /* MSB first */
> +               writeb((addr >> (alen * 8)) & 0xff, &i2c_regs->tfr);
> +       }
> +
> +       return 0;
> +}
> +
> +/*
> + * Internal simplified read function:
> + *   i2c_regs: Pointer to I2C registers for current bus
> + *   chip:     I2C chip address, range 0..127
> + *   addr:     Memory (register) address within the chip
> + *   alen:     Number of bytes to use for addr (typically 1, 2 for larger
> + *             memories, 0 for register type devices with only one register)
> + *   value:    Where to put the data
> + *
> + *   Returns:  0 on success, not 0 on failure
> + */
> +static int i2c_read_byte(struct u8500_i2c_regs *i2c_regs, uchar chip,
> +               uint addr, int alen, uchar *value)
> +{
> +       u32   mcr = 0;
> +
> +       /* Set the address mode to 7 bit */
> +       WRITE_FIELD(mcr, U8500_I2C_MCR_AM, U8500_I2C_MCR_SHIFT_AM, 1);
> +
> +       /* Store the slave address in the master control register */
> +       WRITE_FIELD(mcr, U8500_I2C_MCR_A7, U8500_I2C_MCR_SHIFT_A7, chip);
> +
> +       if (alen != 0) {
> +               /* Master write operation */
> +               mcr &= ~(U8500_I2C_MCR_OP);
> +
> +               /* Configure the Frame length to one byte */
> +               WRITE_FIELD(mcr, U8500_I2C_MCR_LENGTH,
> +                               U8500_I2C_MCR_SHIFT_LENGTH, 1);
> +
> +               /* Repeated start, no stop */
> +               mcr &= ~(U8500_I2C_MCR_STOP);
> +
> +               /* Write Master Control Register */
> +               writel(mcr, &i2c_regs->mcr);
> +
> +               /* send addr/index */
> +               if (i2c_write_addr(i2c_regs, addr, alen) != 0)
> +                       return -1;
> +
> +               /* Check for the Master Transaction Done Without Stop */
> +               if (loop_till_bit_set((void *)&i2c_regs->risr,
> +                                       U8500_I2C_INT_MTDWS,
> +                                       U8500_I2C_ENDAD_COUNTER)) {
> +                       return -1;
> +               }
> +
> +               /* Acknowledge the Master Transaction Done Without Stop */
> +               i2c_set_bit(&i2c_regs->icr, U8500_I2C_INT_MTDWS);
> +       }
> +
> +       /* Master control configuration for read operation  */
> +       mcr |= U8500_I2C_MCR_OP;
> +
> +       /* Configure the STOP condition, we read only one byte */
> +       mcr |= U8500_I2C_MCR_STOP;
> +
> +       /* Set the frame length to one byte, we support only 1 byte reads */
> +       WRITE_FIELD(mcr, U8500_I2C_MCR_LENGTH, U8500_I2C_MCR_SHIFT_LENGTH, 1);
> +
> +       i2c_write_field(&i2c_regs->mcr, U8500_I2C_MCR_LENGTH_STOP_OP,
> +                       U8500_I2C_MCR_SHIFT_LENGTH_STOP_OP, mcr);
> +
> +       /*
> +        * receive_data_polling
> +        */
> +
> +       /* Wait until the Rx FIFO is not empty */
> +       if (loop_till_bit_clear((void *)&i2c_regs->risr,
> +                                       U8500_I2C_INT_RXFE,
> +                                       U8500_I2C_ENDAD_COUNTER))
> +               return -1;
> +
> +       /* Read the data byte from Rx FIFO */
> +       *value = readb(&i2c_regs->rfr);
> +
> +       /* Wait until the work is done */
> +       if (loop_till_bit_set((void *)&i2c_regs->risr, U8500_I2C_INT_MTD,
> +                               U8500_I2C_ENDAD_COUNTER))
> +               return -1;
> +
> +       /* Acknowledge the Master Transaction Done */
> +       i2c_set_bit(&i2c_regs->icr, U8500_I2C_INT_MTD);
> +
> +       /* If MTD is set, Master Transaction Done Without Stop is set too */
> +       i2c_set_bit(&i2c_regs->icr, U8500_I2C_INT_MTDWS);
> +
> +       return 0;
> +}
> +
> +/*
> + * Internal simplified write function:
> + *   i2c_regs: Pointer to I2C registers for current bus
> + *   chip:     I2C chip address, range 0..127
> + *   addr:     Memory (register) address within the chip
> + *   alen:     Number of bytes to use for addr (typically 1, 2 for larger
> + *             memories, 0 for register type devices with only one register)
> + *   data:     Where to read the data
> + *   len:      How many bytes to write
> + *
> + *   Returns:  0 on success, not 0 on failure
> + */
> +static int __i2c_write(struct u8500_i2c_regs *i2c_regs, u8 chip, uint addr,
> +               int alen, u8 *data, int len)
> +{
> +       int i;
> +       u32 mcr = 0;
> +
> +       /* Set the address mode to 7 bit */
> +       WRITE_FIELD(mcr, U8500_I2C_MCR_AM, U8500_I2C_MCR_SHIFT_AM, 1);
> +
> +       /* Store the slave address in the master control register */
> +       WRITE_FIELD(mcr, U8500_I2C_MCR_A7, U8500_I2C_MCR_SHIFT_A7, chip);
> +
> +       /* Write operation */
> +       mcr &= ~(U8500_I2C_MCR_OP);
> +
> +       /* Current transaction is terminated by STOP condition */
> +       mcr |= U8500_I2C_MCR_STOP;
> +
> +       /* Frame length: addr byte + len */
> +       WRITE_FIELD(mcr, U8500_I2C_MCR_LENGTH, U8500_I2C_MCR_SHIFT_LENGTH,
> +                       (alen + len));
> +
> +       /* Write MCR register */
> +       writel(mcr, &i2c_regs->mcr);
> +
> +       if (i2c_write_addr(i2c_regs, addr, alen) != 0)
> +               return -1;
> +
> +       for (i = 0; i < len; i++) {
> +               /* Wait until the Tx FIFO is not full */
> +               if (loop_till_bit_clear((void *)&i2c_regs->risr,
> +                                       U8500_I2C_INT_TXFF,
> +                                       U8500_I2C_ENDAD_COUNTER))
> +                       return -1;
> +
> +               /* it is a 32 bit register with upper 24 reserved R/O */
> +               writeb(data[i], &i2c_regs->tfr);
> +       }
> +
> +       /* Check for Master Transaction Done */
> +       if (loop_till_bit_set((void *)&i2c_regs->risr,
> +                                       U8500_I2C_INT_MTD,
> +                                       U8500_I2C_ENDAD_COUNTER)) {
> +               printf("i2c_write_byte error2: risr %08x\n",
> +                               i2c_regs->risr);
> +               return -1;
> +       }
> +
> +       /* Acknowledge Master Transaction Done */
> +       i2c_set_bit(&i2c_regs->icr, U8500_I2C_INT_MTD);
> +
> +       /* Acknowledge Master Transaction Done Without Stop */
> +       i2c_set_bit(&i2c_regs->icr, U8500_I2C_INT_MTDWS);
> +
> +       return 0;
> +}
> +
> +/*
> + * Probe the given I2C chip address. Returns 0 if a chip responded,
> + * not 0 on failure.
> + */
> +int i2c_probe(uchar chip)
> +{
> +       u32 mcr = 0;
> +       struct u8500_i2c_regs *i2c_regs;
> +
> +       if (chip == CONFIG_SYS_I2C_SLAVE)
> +               return 1;
> +
> +       i2c_regs = i2c_dev[i2c_bus_num];
> +
> +       /* Set the address mode to 7 bit */
> +       WRITE_FIELD(mcr, U8500_I2C_MCR_AM, U8500_I2C_MCR_SHIFT_AM, 1);
> +
> +       /* Store the slave address in the master control register */
> +       WRITE_FIELD(mcr, U8500_I2C_MCR_A10, U8500_I2C_MCR_SHIFT_A7, chip);
> +
> +       /* Read operation */
> +       mcr |= U8500_I2C_MCR_OP;
> +
> +       /* Set the frame length to one byte */
> +       WRITE_FIELD(mcr, U8500_I2C_MCR_LENGTH, U8500_I2C_MCR_SHIFT_LENGTH, 1);
> +
> +       /* Current transaction is terminated by STOP condition */
> +       mcr |= U8500_I2C_MCR_STOP;
> +
> +       /* Write MCR register */
> +       writel(mcr, &i2c_regs->mcr);
> +
> +       /* Wait until the Rx Fifo is not empty */
> +       if (loop_till_bit_clear((void *)&i2c_regs->risr,
> +                                       U8500_I2C_INT_RXFE,
> +                                       U8500_I2C_ENDAD_COUNTER)) {
> +               i2c_abort(i2c_regs);
> +               return -1;
> +       }
> +
> +       flush_fifo(i2c_regs);
> +
> +       /* Acknowledge the Master Transaction Done */
> +       i2c_set_bit(&i2c_regs->icr, U8500_I2C_INT_MTD);
> +
> +       /* Acknowledge the Master Transaction Done Without Stop */
> +       i2c_set_bit(&i2c_regs->icr, U8500_I2C_INT_MTDWS);
> +
> +       return 0;
> +}
> +
> +/*
> + * Read/Write interface:
> + *   chip:    I2C chip address, range 0..127
> + *   addr:    Memory (register) address within the chip
> + *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
> + *              memories, 0 for register type devices with only one
> + *              register)
> + *   buffer:  Where to read/write the data
> + *   len:     How many bytes to read/write
> + *
> + *   Returns: 0 on success, not 0 on failure
> + */
> +int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
> +{
> +       int i;
> +       int rc;
> +       struct u8500_i2c_regs *i2c_regs;
> +
> +       if (alen > 2) {
> +               debug("I2C read: addr len %d not supported\n", alen);
> +               return 1;
> +       }
> +
> +       i2c_regs = i2c_dev[i2c_bus_num];
> +
> +       for (i = 0; i < len; i++) {
> +               rc = i2c_read_byte(i2c_regs, chip, addr + i, alen, &buffer[i]);
> +               if (rc != 0) {
> +                       debug("I2C read: I/O error: %d\n", rc);
> +                       i2c_abort(i2c_regs);
> +                       return rc;
> +               }
> +       }
> +
> +       return 0;
> +}
> +
> +int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
> +{
> +       int rc;
> +       struct u8500_i2c_regs *i2c_regs;
> +       i2c_regs = i2c_dev[i2c_bus_num];
> +
> +       rc = __i2c_write(i2c_regs, chip, addr, alen, buffer,
> +                       len);
> +       if (rc != 0) {
> +               debug("I2C write: I/O error\n");
> +               i2c_abort(i2c_regs);
> +               return rc;
> +       }
> +       return 0;
> +}
> +
> +int i2c_set_bus_num(unsigned int bus)
> +{
> +       if (bus > ARRAY_SIZE(i2c_dev) - 1) {
> +               debug("i2c_set_bus_num: only up to bus %d supported\n",
> +                               ARRAY_SIZE(i2c_dev)-1);
> +               return -1;
> +       }
> +
> +       i2c_bus_num = bus;
> +
> +       if (!bus_initialized[i2c_bus_num])
> +               i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
> +
> +       return 0;
> +}
> +
> +int i2c_set_bus_speed(unsigned int speed)
> +{
> +
> +       if (speed > U8500_I2C_MAX_STANDARD_SCL) {
> +               debug("i2c_set_bus_speed: only up to %d supported\n",
> +                               U8500_I2C_MAX_STANDARD_SCL);
> +               return -1;
> +       }
> +
> +       /* sets as side effect i2c_bus_speed[i2c_bus_num] */
> +       i2c_init(speed, CONFIG_SYS_I2C_SLAVE);
> +
> +       return 0;
> +}
> +
> +unsigned int i2c_get_bus_num(void)
> +{
> +       return i2c_bus_num;
> +}
> +
> +unsigned int i2c_get_bus_speed(void)
> +{
> +       return i2c_bus_speed[i2c_bus_num];
> +}
> diff --git a/drivers/i2c/u8500_i2c.h b/drivers/i2c/u8500_i2c.h
> new file mode 100644
> index 0000000..91dbd3e
> --- /dev/null
> +++ b/drivers/i2c/u8500_i2c.h
> @@ -0,0 +1,194 @@
> +/*
> + * 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 <asm/arch/u8500.h>
> +
> +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 U8500_I2C_CR_PE          0x0001        /* Peripheral enable */
> +#define U8500_I2C_CR_OM          0x0006        /* Operation mode */
> +#define U8500_I2C_CR_SAM         0x0008        /* Slave Addressing mode */
> +#define U8500_I2C_CR_SM          0x0030        /* Speed mode */
> +#define U8500_I2C_CR_SGCM        0x0040        /* Slave General call mode */
> +#define U8500_I2C_CR_FTX         0x0080        /* Flush Transmit */
> +#define U8500_I2C_CR_FRX         0x0100        /* Flush Receive */
> +#define U8500_I2C_CR_DMA_TX_EN   0x0200        /* DMA TX Enable */
> +#define U8500_I2C_CR_DMA_RX_EN   0x0400        /* DMA Rx Enable */
> +#define U8500_I2C_CR_DMA_SLE     0x0800        /* DMA Synchronization Logic enable */
> +#define U8500_I2C_CR_LM          0x1000        /* Loop back mode */
> +#define U8500_I2C_CR_FON         0x6000        /* Filtering On */
> +
> +/* shift valus for control register bit fields */
> +#define U8500_I2C_CR_SHIFT_PE          0       /* Peripheral enable */
> +#define U8500_I2C_CR_SHIFT_OM          1       /* Operation mode */
> +#define U8500_I2C_CR_SHIFT_SAM         3       /* Slave Addressing mode */
> +#define U8500_I2C_CR_SHIFT_SM          4       /* Speed mode */
> +#define U8500_I2C_CR_SHIFT_SGCM                6       /* Slave General call mode */
> +#define U8500_I2C_CR_SHIFT_FTX         7       /* Flush Transmit */
> +#define U8500_I2C_CR_SHIFT_FRX         8       /* Flush Receive */
> +#define U8500_I2C_CR_SHIFT_DMA_TX_EN   9       /* DMA TX Enable */
> +#define U8500_I2C_CR_SHIFT_DMA_RX_EN   10      /* DMA Rx Enable */
> +#define U8500_I2C_CR_SHIFT_DMA_SLE     11      /* DMA Synch Logic enable */
> +#define U8500_I2C_CR_SHIFT_LM          12      /* Loop back mode */
> +#define U8500_I2C_CR_SHIFT_FON         13      /* Filtering On */
> +
> +/* bus operation modes */
> +#define U8500_I2C_BUS_SLAVE_MODE               0
> +#define U8500_I2C_BUS_MASTER_MODE              1
> +#define U8500_I2C_BUS_MASTER_SLAVE_MODE        2
> +
> +
> +/* Slave control register*/
> +
> +/* Mask values slave control register */
> +#define U8500_I2C_SCR_ADDR                   0x3FF
> +#define U8500_I2C_SCR_DATA_SETUP_TIME        0xFFFF0000
> +
> +/* Shift values for Slave control register */
> +#define U8500_I2C_SCR_SHIFT_ADDR               0
> +#define U8500_I2C_SCR_SHIFT_DATA_SETUP_TIME    16
> +
> +
> +/* Master Control Register */
> +
> +/* Mask values for Master control register */
> +#define U8500_I2C_MCR_OP       0x00000001      /* Operation */
> +#define U8500_I2C_MCR_A7       0x000000FE      /* LSB bits of Address */
> +#define U8500_I2C_MCR_EA10     0x00000700      /* Extended Address */
> +#define U8500_I2C_MCR_SB       0x00000800      /* Start byte procedure */
> +#define U8500_I2C_MCR_AM       0x00003000      /* Address type */
> +#define U8500_I2C_MCR_STOP     0x00004000      /* stop condition */
> +#define U8500_I2C_MCR_LENGTH   0x03FF8000      /* Frame length */
> +#define U8500_I2C_MCR_A10      0x000007FE      /* Enable 10 bit address */
> +/* mask for length field,stop and operation  */
> +#define U8500_I2C_MCR_LENGTH_STOP_OP   0x3FFC001
> +
> +/* Shift values for Master control values */
> +#define U8500_I2C_MCR_SHIFT_OP         0       /* Operation */
> +#define U8500_I2C_MCR_SHIFT_A7         1       /* LSB bits of Address */
> +#define U8500_I2C_MCR_SHIFT_EA10       8       /* Extended Address */
> +#define U8500_I2C_MCR_SHIFT_SB         11      /* Start byte procedure */
> +#define U8500_I2C_MCR_SHIFT_AM         12      /* Address type */
> +#define U8500_I2C_MCR_SHIFT_STOP       14      /* stop condition */
> +#define U8500_I2C_MCR_SHIFT_LENGTH     15      /* Frame length */
> +#define U8500_I2C_MCR_SHIFT_A10                1       /* Enable 10 bit address */
> +
> +#define U8500_I2C_MCR_SHIFT_LENGTH_STOP_OP     0
> +
> +
> +/* Status Register */
> +
> +/* Mask values for Status register */
> +#define U8500_I2C_SR_OP        0x00000003      /* Operation */
> +#define U8500_I2C_SR_STATUS    0x0000000C      /* Controller Status */
> +#define U8500_I2C_SR_CAUSE     0x00000070      /* Abort Cause */
> +#define U8500_I2C_SR_TYPE      0x00000180      /* Receive Type */
> +#define U8500_I2C_SR_LENGTH    0x000FF700      /* Transfer length */
> +
> +/* Shift values for Status register */
> +#define U8500_I2C_SR_SHIFT_OP          0       /* Operation */
> +#define U8500_I2C_SR_SHIFT_STATUS      2       /* Controller Status */
> +#define U8500_I2C_SR_SHIFT_CAUSE       4       /* Abort Cause */
> +#define U8500_I2C_SR_SHIFT_TYPE        7       /* Receive Type */
> +#define U8500_I2C_SR_SHIFT_LENGTH      9       /* Transfer length */
> +
> +/* abort cause */
> +#define        U8500_I2C_NACK_ADDR     0
> +#define        U8500_I2C_NACK_DATA     1
> +#define        U8500_I2C_ACK_MCODE     2
> +#define        U8500_I2C_ARB_LOST      3
> +#define        U8500_I2C_BERR_START    4
> +#define        U8500_I2C_BERR_STOP     5
> +#define        U8500_I2C_OVFL  6
> +
> +
> +/* Baud rate counter registers */
> +
> +/* Mask values for Baud rate counter register */
> +#define U8500_I2C_BRCR_BRCNT2  0xFFFF          /* Baud Rate Cntr BRCR for HS */
> +#define U8500_I2C_BRCR_BRCNT1  0xFFFF0000      /* BRCR for Standard and Fast */
> +
> +/* Shift values for the Baud rate counter register */
> +#define U8500_I2C_BRCR_SHIFT_BRCNT2    0
> +#define U8500_I2C_BRCR_SHIFT_BRCNT1    16
> +
> +
> +/* Interrupt Register  */
> +
> +/* Mask values for Interrupt registers */
> +#define U8500_I2C_INT_TXFE     0x00000001      /* Tx fifo empty */
> +#define U8500_I2C_INT_TXFNE    0x00000002      /* Tx Fifo nearly empty */
> +#define U8500_I2C_INT_TXFF     0x00000004      /* Tx Fifo Full */
> +#define U8500_I2C_INT_TXFOVR   0x00000008      /* Tx Fifo over run */
> +#define U8500_I2C_INT_RXFE     0x00000010      /* Rx Fifo Empty */
> +#define U8500_I2C_INT_RXFNF    0x00000020      /* Rx Fifo nearly empty */
> +#define U8500_I2C_INT_RXFF     0x00000040      /* Rx Fifo Full  */
> +#define U8500_I2C_INT_RFSR     0x00010000      /* Read From slave request */
> +#define U8500_I2C_INT_RFSE     0x00020000      /* Read from slave empty */
> +#define U8500_I2C_INT_WTSR     0x00040000      /* Write to Slave request */
> +#define U8500_I2C_INT_MTD      0x00080000      /* Master Transcation Done*/
> +#define U8500_I2C_INT_STD      0x00100000      /* Slave Transaction Done */
> +#define U8500_I2C_INT_MAL      0x01000000      /* Master Arbitation Lost */
> +#define U8500_I2C_INT_BERR     0x02000000      /* Bus Error */
> +#define U8500_I2C_INT_MTDWS    0x10000000      /* Master Tran Done wo/ Stop */
> +
> +/* Max clocks (Hz) */
> +#define U8500_I2C_MAX_STANDARD_SCL     100000
> +#define U8500_I2C_MAX_FAST_SCL         400000
> +#define U8500_I2C_MAX_HIGH_SPEED_SCL   3400000
> +
> +#endif /* _U8500_I2C_H_ */
> --
> 1.7.1
>
>

Heiko, can you commit this to the i2c tree?  Thanks, it is needed for
the board patches in this series.


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