Re: [PATCH] i2c: imx: add macros and printk to make debug easy

[Richard Zhao <linuxzsc-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>]

On Wed, Sep 30, 2009 at 1:48 PM, Richard Zhao <linuxzsc-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> When CONFIG_I2C_DEBUG_BUS is enabled, it helps dump registers at operation
> fail condition, and print i2c_msg to xfer.
>
> Signed-off-by: Richard Zhao <linuxzsc-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> ---
>  drivers/i2c/busses/i2c-imx.c |   49 ++++++++++++++++++++++++++++++++++++------
>  1 files changed, 42 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
> index c1e541c..87faea4 100644
> --- a/drivers/i2c/busses/i2c-imx.c
> +++ b/drivers/i2c/busses/i2c-imx.c
> @@ -125,6 +125,20 @@ struct imx_i2c_struct {
>  /** Functions for IMX I2C adapter driver ***************************************
>  *******************************************************************************/
>
> +#ifdef CONFIG_I2C_DEBUG_BUS
> +#define reg_dump(i2c_imx) \
> +{ \
> +       printk(KERN_DEBUG "fun %s:%d ", __func__, __LINE__); \
> +       printk(KERN_DEBUG "IADR %02x IFDR %02x I2CR %02x I2SR %02x\n", \
> +               readb(i2c_imx->base + IMX_I2C_IADR), \
> +               readb(i2c_imx->base + IMX_I2C_IFDR), \
> +               readb(i2c_imx->base + IMX_I2C_I2CR), \
> +               readb(i2c_imx->base + IMX_I2C_I2SR)); \
> +}
> +#else
> +#define reg_dump(i2c_imx)
> +#endif
> +
>  static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy)
>  {
>        unsigned long orig_jiffies = jiffies;
> @@ -146,6 +160,7 @@ static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy)
>                if (time_after(jiffies, orig_jiffies + HZ / 1000)) {
>                        dev_dbg(&i2c_imx->adapter.dev,
>                                "<%s> I2C bus is busy\n", __func__);
> +                       reg_dump(i2c_imx);
>                        return -EIO;
>                }
>                schedule();
> @@ -164,9 +179,11 @@ static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx)
>
>        if (unlikely(result < 0)) {
>                dev_dbg(&i2c_imx->adapter.dev, "<%s> result < 0\n", __func__);
> +               reg_dump(i2c_imx);
>                return result;
>        } else if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) {
>                dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__);
> +               reg_dump(i2c_imx);
>                return -ETIMEDOUT;
>        }
>        dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__);
> @@ -178,6 +195,7 @@ static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx)
>  {
>        if (readb(i2c_imx->base + IMX_I2C_I2SR) & I2SR_RXAK) {
>                dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__);
> +               reg_dump(i2c_imx);
>                return -EIO;  /* No ACK */
>        }
>
> @@ -197,17 +215,20 @@ static int i2c_imx_start(struct imx_i2c_struct *i2c_imx)
>        writeb(I2CR_IEN, i2c_imx->base + IMX_I2C_I2CR);
>
>        result = i2c_imx_bus_busy(i2c_imx, 0);
> -       if (result)
> +       if (result) {
> +               reg_dump(i2c_imx);
>                return result;
> +       }
>
>        /* Start I2C transaction */
>        temp = readb(i2c_imx->base + IMX_I2C_I2CR);
>        temp |= I2CR_MSTA;
>        writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
>        result = i2c_imx_bus_busy(i2c_imx, 1);
> -       if (result)
> +       if (result) {
> +               reg_dump(i2c_imx);
>                return result;
> -
> +       }
>        temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK;
>        writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
>        return result;
> @@ -228,7 +249,8 @@ static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
>         */
>        udelay(i2c_imx->disable_delay);
>
> -       i2c_imx_bus_busy(i2c_imx, 0);
> +       if (i2c_imx_bus_busy(i2c_imx, 0))
> +               reg_dump(i2c_imx);
>
>        /* Disable I2C controller */
>        writeb(0, i2c_imx->base + IMX_I2C_I2CR);
> @@ -389,7 +411,18 @@ static int i2c_imx_xfer(struct i2c_adapter *adapter,
>        struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
>
>        dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
> -
> +#ifdef CONFIG_I2C_DEBUG_BUS
> +       for (i = 0; i < num; i++) {
> +               printk(KERN_DEBUG "msg%d addr %02x RD %d cnt %d d:", i,
> +                       msgs[i].addr, msgs[i].flags & I2C_M_RD, msgs[i].len);
> +               if (!(msgs[i].flags & I2C_M_RD)) {
> +                       int j;
> +                       for (j = 0; j < msgs[i].len; j++)
> +                               printk("%02x ", msgs[i].buf[j]);
> +               }
> +               printk("\n");
> +       }
> +#endif
>        /* Start I2C transfer */
>        result = i2c_imx_start(i2c_imx);
>        if (result)
> @@ -404,8 +437,10 @@ static int i2c_imx_xfer(struct i2c_adapter *adapter,
>                        temp |= I2CR_RSTA;
>                        writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
>                        result =  i2c_imx_bus_busy(i2c_imx, 1);
> -                       if (result)
> +                       if (result) {
> +                               reg_dump(i2c_imx);
>                                goto fail0;
> +                       }
>                }
>                dev_dbg(&i2c_imx->adapter.dev,
>                        "<%s> transfer message: %d\n", __func__, i);
> @@ -562,7 +597,7 @@ static int __init i2c_imx_probe(struct platform_device *pdev)
>                res_size, i2c_imx->res->start);
>        dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n",
>                i2c_imx->adapter.name);
> -       dev_dbg(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
> +       dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
>
>        return 0;   /* Return OK */
>
> --
> 1.6.0.4
>
>

Sorry, I forgot to add patch NO. Please ignore theses patch.
 Richard