i2c: qup: minor code reorganization for use_dma
authorAbhishek Sahu <absahu@codeaurora.org>
Mon, 12 Mar 2018 13:14:52 +0000 (18:44 +0530)
committerWolfram Sang <wsa@the-dreams.de>
Sat, 24 Mar 2018 12:19:17 +0000 (13:19 +0100)
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: Austin Christ <austinwc@codeaurora.org>
Reviewed-by: Andy Gross <andy.gross@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
drivers/i2c/busses/i2c-qup.c

index 75e9819..f6ea074 100644 (file)
@@ -181,6 +181,8 @@ 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;
@@ -1288,7 +1290,7 @@ 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;
@@ -1317,13 +1319,12 @@ 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;
@@ -1347,15 +1348,17 @@ 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);