> -----Original Message----- > From: linux-omap-owner@xxxxxxxxxxxxxxx [mailto:linux-omap- > owner@xxxxxxxxxxxxxxx] On Behalf Of Igor Mazanov > Sent: Tuesday, June 23, 2009 4:43 PM > To: linux-omap@xxxxxxxxxxxxxxx > 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 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
