target/linux/ipq40xx/patches-4.14/088-0003-i2c-qup-minor-code-reorganization-for-use_dma.patch

   1 From eb422b539c1f39faf576826b54be93e84d9cb32a Mon Sep 17 00:00:00 2001
   2 From: Abhishek Sahu <absahu@codeaurora.org>
   3 Date: Mon, 12 Mar 2018 18:44:52 +0530
   4 Subject: [PATCH 03/13] i2c: qup: minor code reorganization for use_dma
   5
   6 1. Assigns use_dma in qup_dev structure itself which will
   7    help in subsequent patches to determine the mode in IRQ handler.
   8 2. Does minor code reorganization for loops to reduce the
   9    unnecessary comparison and assignment.
  10
  11 Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
  12 Reviewed-by: Austin Christ <austinwc@codeaurora.org>
  13 Reviewed-by: Andy Gross <andy.gross@linaro.org>
  14 Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
  15 ---
  16  drivers/i2c/busses/i2c-qup.c | 19 +++++++++++--------
  17  1 file changed, 11 insertions(+), 8 deletions(-)
  18
  19 --- a/drivers/i2c/busses/i2c-qup.c
  20 +++ b/drivers/i2c/busses/i2c-qup.c
  21 @@ -181,6 +181,8 @@ struct qup_i2c_dev {
  22
  23         /* dma parameters */
  24         bool                    is_dma;
  25 +       /* To check if the current transfer is using DMA */
  26 +       bool                    use_dma;
  27         struct                  dma_pool *dpool;
  28         struct                  qup_i2c_tag start_tag;
  29         struct                  qup_i2c_bam brx;
  30 @@ -1288,7 +1290,7 @@ static int qup_i2c_xfer_v2(struct i2c_ad
  31                            int num)
  32  {
  33         struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
  34 -       int ret, len, idx = 0, use_dma = 0;
  35 +       int ret, len, idx = 0;
  36
  37         qup->bus_err = 0;
  38         qup->qup_err = 0;
  39 @@ -1317,13 +1319,12 @@ static int qup_i2c_xfer_v2(struct i2c_ad
  40                         len = (msgs[idx].len > qup->out_fifo_sz) ||
  41                               (msgs[idx].len > qup->in_fifo_sz);
  42
  43 -                       if ((!is_vmalloc_addr(msgs[idx].buf)) && len) {
  44 -                               use_dma = 1;
  45 -                        } else {
  46 -                               use_dma = 0;
  47 +                       if (is_vmalloc_addr(msgs[idx].buf) || !len)
  48                                 break;
  49 -                       }
  50                 }
  51 +
  52 +               if (idx == num)
  53 +                       qup->use_dma = true;
  54         }
  55
  56         idx = 0;
  57 @@ -1347,15 +1348,17 @@ static int qup_i2c_xfer_v2(struct i2c_ad
  58
  59                 reinit_completion(&qup->xfer);
  60
  61 -               if (use_dma) {
  62 +               if (qup->use_dma) {
  63                         ret = qup_i2c_bam_xfer(adap, &msgs[idx], num);
  64 +                       qup->use_dma = false;
  65 +                       break;
  66                 } else {
  67                         if (msgs[idx].flags & I2C_M_RD)
  68                                 ret = qup_i2c_read_one_v2(qup, &msgs[idx]);
  69                         else
  70                                 ret = qup_i2c_write_one_v2(qup, &msgs[idx]);
  71                 }
  72 -       } while ((idx++ < (num - 1)) && !use_dma && !ret);
  73 +       } while ((idx++ < (num - 1)) && !ret);
  74
  75         if (!ret)
  76                 ret = qup_i2c_change_state(qup, QUP_RESET_STATE);