> -----Original Message-----
> From: [email protected] [mailto:linux-omap-
> [email protected]] On Behalf Of Igor Mazanov
> Sent: Tuesday, June 23, 2009 4:43 PM
> To: [email protected]
> Subject: Re: [PATCH] [RFC][OMAP3:I2C]Workaround for OMAP3430 I2C silicon
> errata 1.153
> 
> /*
>   * Is there a bug in the OMAP5910 I2C controller? It
>   * generates a bunch of fake XRDY interrupts under high load.
>   * As result, there is a very high chance to have a situation
>   * when dev->buf_len = 0 already, but I2C_CNT != 0. So, there
>   * is no ARDY irq then, no complete_cmd, controller timed out
>   * issues...
>   *
>   * Workaround:
>   *
>   * When we get XRDY interrupt without transmit underflow flag
>   * (XUDF bit in the I2C_STAT register), delay for 100 microsecs
>   * and ignore it.
>   *
>   * We write data into I2C_DATA register in case of transmit
>   * underflow condition ONLY.
>   */
> if (stat & OMAP_I2C_STAT_XRDY) {
>       if (!(stat & OMAP_I2C_STAT_XUDF)) {
>               udelay(100);
>               continue;
>       } else {
>               w = 0;
>               if (dev->buf_len) {
>                       w = *dev->buf++;
>                       dev->buf_len--;
>                       if (dev->buf_len) {
>                               w |= *dev->buf++ << 8;
>                               dev->buf_len--;
>                       }
>                       omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
>               } else {
>                       dev_err(dev->dev, "XRDY IRQ while no "
>                                               "data to send\n");
>                       break;
>               }
>               continue;
>       }
> }
> 
Could you submit a patch please?


Regards,
Nishanth Menon
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