[02/12] i2c: qup: minor code reorganization for use_dma

Message ID 1517644697-30806-3-git-send-email-absahu@codeaurora.org
State Superseded
Headers show
Series
  • Major code reorganization to make all i2c transfers working
Related show

Commit Message

Abhishek Sahu Feb. 3, 2018, 7:58 a.m.
1. Assigns use_dma in qup_dev structure itself which will
   help in subsequent patches to determine the mode in IRQ handler.
2. Does minor code reorganization for loops to reduce the
   unnecessary comparison and assignment.

Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
---
 drivers/i2c/busses/i2c-qup.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

Comments

Christ, Austin Feb. 27, 2018, 9:48 p.m. | #1
Tested on Centriq 2400

Reviewed-by: Austin Christ <austinwc@codeaurora.org>

On 2/3/2018 12:58 AM, Abhishek Sahu wrote:
> 1. Assigns use_dma in qup_dev structure itself which will
>     help in subsequent patches to determine the mode in IRQ handler.
> 2. Does minor code reorganization for loops to reduce the
>     unnecessary comparison and assignment.
> 
> Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
> ---
>   drivers/i2c/busses/i2c-qup.c | 19 +++++++++++--------
>   1 file changed, 11 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c
> index 9faa26c41a..c68f433 100644
> --- a/drivers/i2c/busses/i2c-qup.c
> +++ b/drivers/i2c/busses/i2c-qup.c
> @@ -190,6 +190,8 @@ struct qup_i2c_dev {
>   
>   	/* dma parameters */
>   	bool			is_dma;
> +	/* To check if the current transfer is using DMA */
> +	bool			use_dma;
>   	struct			dma_pool *dpool;
>   	struct			qup_i2c_tag start_tag;
>   	struct			qup_i2c_bam brx;
> @@ -1297,7 +1299,7 @@ static int qup_i2c_xfer_v2(struct i2c_adapter *adap,
>   			   int num)
>   {
>   	struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
> -	int ret, len, idx = 0, use_dma = 0;
> +	int ret, len, idx = 0;
>   
>   	qup->bus_err = 0;
>   	qup->qup_err = 0;
> @@ -1326,13 +1328,12 @@ static int qup_i2c_xfer_v2(struct i2c_adapter *adap,
>   			len = (msgs[idx].len > qup->out_fifo_sz) ||
>   			      (msgs[idx].len > qup->in_fifo_sz);
>   
> -			if ((!is_vmalloc_addr(msgs[idx].buf)) && len) {
> -				use_dma = 1;
> -			 } else {
> -				use_dma = 0;
> +			if (is_vmalloc_addr(msgs[idx].buf) || !len)
>   				break;
> -			}
>   		}
> +
> +		if (idx == num)
> +			qup->use_dma = true;
>   	}
>   
>   	idx = 0;
> @@ -1356,15 +1357,17 @@ static int qup_i2c_xfer_v2(struct i2c_adapter *adap,
>   
>   		reinit_completion(&qup->xfer);
>   
> -		if (use_dma) {
> +		if (qup->use_dma) {
>   			ret = qup_i2c_bam_xfer(adap, &msgs[idx], num);
> +			qup->use_dma = false;
> +			break;
>   		} else {
>   			if (msgs[idx].flags & I2C_M_RD)
>   				ret = qup_i2c_read_one_v2(qup, &msgs[idx]);
>   			else
>   				ret = qup_i2c_write_one_v2(qup, &msgs[idx]);
>   		}
> -	} while ((idx++ < (num - 1)) && !use_dma && !ret);
> +	} while ((idx++ < (num - 1)) && !ret);
>   
>   	if (!ret)
>   		ret = qup_i2c_change_state(qup, QUP_RESET_STATE);
>
Andy Gross Feb. 27, 2018, 10:26 p.m. | #2
On Sat, Feb 03, 2018 at 01:28:07PM +0530, Abhishek Sahu wrote:
> 1. Assigns use_dma in qup_dev structure itself which will
>    help in subsequent patches to determine the mode in IRQ handler.
> 2. Does minor code reorganization for loops to reduce the
>    unnecessary comparison and assignment.
> 
> Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>

Reviewed-by: Andy Gross <andy.gross@linaro.org>

Patch

diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c
index 9faa26c41a..c68f433 100644
--- a/drivers/i2c/busses/i2c-qup.c
+++ b/drivers/i2c/busses/i2c-qup.c
@@ -190,6 +190,8 @@  struct qup_i2c_dev {
 
 	/* dma parameters */
 	bool			is_dma;
+	/* To check if the current transfer is using DMA */
+	bool			use_dma;
 	struct			dma_pool *dpool;
 	struct			qup_i2c_tag start_tag;
 	struct			qup_i2c_bam brx;
@@ -1297,7 +1299,7 @@  static int qup_i2c_xfer_v2(struct i2c_adapter *adap,
 			   int num)
 {
 	struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
-	int ret, len, idx = 0, use_dma = 0;
+	int ret, len, idx = 0;
 
 	qup->bus_err = 0;
 	qup->qup_err = 0;
@@ -1326,13 +1328,12 @@  static int qup_i2c_xfer_v2(struct i2c_adapter *adap,
 			len = (msgs[idx].len > qup->out_fifo_sz) ||
 			      (msgs[idx].len > qup->in_fifo_sz);
 
-			if ((!is_vmalloc_addr(msgs[idx].buf)) && len) {
-				use_dma = 1;
-			 } else {
-				use_dma = 0;
+			if (is_vmalloc_addr(msgs[idx].buf) || !len)
 				break;
-			}
 		}
+
+		if (idx == num)
+			qup->use_dma = true;
 	}
 
 	idx = 0;
@@ -1356,15 +1357,17 @@  static int qup_i2c_xfer_v2(struct i2c_adapter *adap,
 
 		reinit_completion(&qup->xfer);
 
-		if (use_dma) {
+		if (qup->use_dma) {
 			ret = qup_i2c_bam_xfer(adap, &msgs[idx], num);
+			qup->use_dma = false;
+			break;
 		} else {
 			if (msgs[idx].flags & I2C_M_RD)
 				ret = qup_i2c_read_one_v2(qup, &msgs[idx]);
 			else
 				ret = qup_i2c_write_one_v2(qup, &msgs[idx]);
 		}
-	} while ((idx++ < (num - 1)) && !use_dma && !ret);
+	} while ((idx++ < (num - 1)) && !ret);
 
 	if (!ret)
 		ret = qup_i2c_change_state(qup, QUP_RESET_STATE);