+Wolfram Sang >-----Original Message----- >From: linux-arm-kernel [mailto:linux-arm-kernel-bounces@xxxxxxxxxxxxxxxxxxx] On Behalf Of Sricharan R >Sent: Friday, June 10, 2016 11:38 PM >To: linux-arm-msm@xxxxxxxxxxxxxxx; ntelkar@xxxxxxxxxxxxxx; galak@xxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; >andy.gross@xxxxxxxxxx; linux-i2c@xxxxxxxxxxxxxxx; agross@xxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; >nkaje@xxxxxxxxxxxxxx; absahu@xxxxxxxxxxxxxx >Cc: sricharan@xxxxxxxxxxxxxx >Subject: [PATCH V4 3/3] i2c: qup: Fix error handling > >Among the bus errors reported from the QUP_MASTER_STATUS register >only NACK is considered and transfer gets suspended, while >other errors are ignored. Correct this and suspend the transfer >for other errors as well. This avoids unnecessary 'timeouts' which >happens when waiting for events that would never happen when there >is already an error condition on the bus. Also the error handling >procedure should be the same for both NACK and other bus errors in >case of dma mode. So correct that as well. > >Signed-off-by: Sricharan R <sricharan@xxxxxxxxxxxxxx> >--- > drivers/i2c/busses/i2c-qup.c | 76 ++++++++++++++++++++++++-------------------- > 1 file changed, 41 insertions(+), 35 deletions(-) > >diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c >index b8116e5..44c80ae 100644 >--- a/drivers/i2c/busses/i2c-qup.c >+++ b/drivers/i2c/busses/i2c-qup.c >@@ -310,6 +310,7 @@ static int qup_i2c_wait_ready(struct qup_i2c_dev *qup, int op, bool val, > u32 opflags; > u32 status; > u32 shift = __ffs(op); >+ int ret = 0; > > len *= qup->one_byte_t; > /* timeout after a wait of twice the max time */ >@@ -321,18 +322,28 @@ static int qup_i2c_wait_ready(struct qup_i2c_dev *qup, int op, bool val, > > if (((opflags & op) >> shift) == val) { > if ((op == QUP_OUT_NOT_EMPTY) && qup->is_last) { >- if (!(status & I2C_STATUS_BUS_ACTIVE)) >- return 0; >+ if (!(status & I2C_STATUS_BUS_ACTIVE)) { >+ ret = 0; >+ goto done; >+ } > } else { >- return 0; >+ ret = 0; >+ goto done; > } > } > >- if (time_after(jiffies, timeout)) >- return -ETIMEDOUT; >- >+ if (time_after(jiffies, timeout)) { >+ ret = -ETIMEDOUT; >+ goto done; >+ } > usleep_range(len, len * 2); > } >+ >+done: >+ if (qup->bus_err || qup->qup_err) >+ ret = (qup->bus_err & QUP_I2C_NACK_FLAG) ? -ENXIO : -EIO; >+ >+ return ret; > } > > static void qup_i2c_set_write_mode_v2(struct qup_i2c_dev *qup, >@@ -793,39 +804,35 @@ static int qup_i2c_bam_do_xfer(struct qup_i2c_dev *qup, struct i2c_msg *msg, > } > > if (ret || qup->bus_err || qup->qup_err) { >- if (qup->bus_err & QUP_I2C_NACK_FLAG) { >- msg--; >- dev_err(qup->dev, "NACK from %x\n", msg->addr); >- ret = -EIO; >+ if (qup_i2c_change_state(qup, QUP_RUN_STATE)) { >+ dev_err(qup->dev, "change to run state timed out"); >+ goto desc_err; >+ } > >- if (qup_i2c_change_state(qup, QUP_RUN_STATE)) { >- dev_err(qup->dev, "change to run state timed out"); >- return ret; >- } >+ if (rx_nents) >+ writel(QUP_BAM_INPUT_EOT, >+ qup->base + QUP_OUT_FIFO_BASE); > >- if (rx_nents) >- writel(QUP_BAM_INPUT_EOT, >- qup->base + QUP_OUT_FIFO_BASE); >+ writel(QUP_BAM_FLUSH_STOP, qup->base + QUP_OUT_FIFO_BASE); > >- writel(QUP_BAM_FLUSH_STOP, >- qup->base + QUP_OUT_FIFO_BASE); >+ qup_i2c_flush(qup); > >- qup_i2c_flush(qup); >+ /* wait for remaining interrupts to occur */ >+ if (!wait_for_completion_timeout(&qup->xfer, HZ)) >+ dev_err(qup->dev, "flush timed out\n"); > >- /* wait for remaining interrupts to occur */ >- if (!wait_for_completion_timeout(&qup->xfer, HZ)) >- dev_err(qup->dev, "flush timed out\n"); >+ qup_i2c_rel_dma(qup); > >- qup_i2c_rel_dma(qup); >- } >+ ret = (qup->bus_err & QUP_I2C_NACK_FLAG) ? -ENXIO : -EIO; > } > >+desc_err: > dma_unmap_sg(qup->dev, qup->btx.sg, tx_nents, DMA_TO_DEVICE); > > if (rx_nents) > dma_unmap_sg(qup->dev, qup->brx.sg, rx_nents, > DMA_FROM_DEVICE); >-desc_err: >+ > return ret; > } > >@@ -841,9 +848,6 @@ static int qup_i2c_bam_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, > if (ret) > goto out; > >- qup->bus_err = 0; >- qup->qup_err = 0; >- > writel(0, qup->base + QUP_MX_INPUT_CNT); > writel(0, qup->base + QUP_MX_OUTPUT_CNT); > >@@ -881,12 +885,8 @@ static int qup_i2c_wait_for_complete(struct qup_i2c_dev *qup, > ret = -ETIMEDOUT; > } > >- if (qup->bus_err || qup->qup_err) { >- if (qup->bus_err & QUP_I2C_NACK_FLAG) { >- dev_err(qup->dev, "NACK from %x\n", msg->addr); >- ret = -EIO; >- } >- } >+ if (qup->bus_err || qup->qup_err) >+ ret = (qup->bus_err & QUP_I2C_NACK_FLAG) ? -ENXIO : -EIO; > > return ret; > } >@@ -1178,6 +1178,9 @@ static int qup_i2c_xfer(struct i2c_adapter *adap, > if (ret < 0) > goto out; > >+ qup->bus_err = 0; >+ qup->qup_err = 0; >+ > writel(1, qup->base + QUP_SW_RESET); > ret = qup_i2c_poll_state(qup, QUP_RESET_STATE); > if (ret) >@@ -1227,6 +1230,9 @@ static int qup_i2c_xfer_v2(struct i2c_adapter *adap, > struct qup_i2c_dev *qup = i2c_get_adapdata(adap); > int ret, len, idx = 0, use_dma = 0; > >+ qup->bus_err = 0; >+ qup->qup_err = 0; >+ > ret = pm_runtime_get_sync(qup->dev); > if (ret < 0) > goto out; >-- >QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux >Foundation > > >_______________________________________________ >linux-arm-kernel mailing list >linux-arm-kernel@xxxxxxxxxxxxxxxxxxx >http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
