target/linux/brcm2708/patches-4.4/0088-bcm2835-dma-Fix-up-convert-to-DMA-pool.patch

   1 From 4c9c5dfadea113fded74c2ab29f96b2109abaa04 Mon Sep 17 00:00:00 2001
   2 From: Matthias Reichl <hias@horus.com>
   3 Date: Mon, 16 Nov 2015 14:05:35 +0000
   4 Subject: [PATCH] bcm2835-dma: Fix up convert to DMA pool
   5
   6 ---
   7  drivers/dma/bcm2835-dma.c | 36 ++++++++++++++++++++++++++----------
   8  1 file changed, 26 insertions(+), 10 deletions(-)
   9
  10 --- a/drivers/dma/bcm2835-dma.c
  11 +++ b/drivers/dma/bcm2835-dma.c
  12 @@ -488,6 +488,17 @@ static struct dma_async_tx_descriptor *b
  13         c->cyclic = true;
  14
  15         return vchan_tx_prep(&c->vc, &d->vd, flags);
  16 +error_cb:
  17 +       i--;
  18 +       for (; i >= 0; i--) {
  19 +               struct bcm2835_cb_entry *cb_entry = &d->cb_list[i];
  20 +
  21 +               dma_pool_free(c->cb_pool, cb_entry->cb, cb_entry->paddr);
  22 +       }
  23 +
  24 +       kfree(d->cb_list);
  25 +       kfree(d);
  26 +       return NULL;
  27  }
  28
  29  static struct dma_async_tx_descriptor *
  30 @@ -534,6 +545,7 @@ bcm2835_dma_prep_slave_sg(struct dma_cha
  31         if (!d)
  32                 return NULL;
  33
  34 +       d->c = c;
  35         d->dir = direction;
  36
  37         if (c->ch >= 8) /* LITE channel */
  38 @@ -553,15 +565,21 @@ bcm2835_dma_prep_slave_sg(struct dma_cha
  39                 d->frames += len / max_size + 1;
  40         }
  41
  42 -       /* Allocate memory for control blocks */
  43 -       d->control_block_size = d->frames * sizeof(struct bcm2835_dma_cb);
  44 -       d->control_block_base = dma_zalloc_coherent(chan->device->dev,
  45 -                       d->control_block_size, &d->control_block_base_phys,
  46 -                       GFP_NOWAIT);
  47 -       if (!d->control_block_base) {
  48 +       d->cb_list = kcalloc(d->frames, sizeof(*d->cb_list), GFP_KERNEL);
  49 +       if (!d->cb_list) {
  50                 kfree(d);
  51                 return NULL;
  52         }
  53 +       /* Allocate memory for control blocks */
  54 +       for (i = 0; i < d->frames; i++) {
  55 +               struct bcm2835_cb_entry *cb_entry = &d->cb_list[i];
  56 +
  57 +               cb_entry->cb = dma_pool_zalloc(c->cb_pool, GFP_ATOMIC,
  58 +                                               &cb_entry->paddr);
  59 +
  60 +               if (!cb_entry->cb)
  61 +                       goto error_cb;
  62 +       }
  63
  64         /*
  65          * Iterate over all SG entries, create a control block
  66 @@ -578,7 +596,7 @@ bcm2835_dma_prep_slave_sg(struct dma_cha
  67
  68                 for (j = 0; j < len; j += max_size) {
  69                         struct bcm2835_dma_cb *control_block =
  70 -                               &d->control_block_base[i + split_cnt];
  71 +                               d->cb_list[i + split_cnt].cb;
  72
  73                         /* Setup addresses */
  74                         if (d->dir == DMA_DEV_TO_MEM) {
  75 @@ -620,9 +638,7 @@ bcm2835_dma_prep_slave_sg(struct dma_cha
  76                         if (i < sg_len - 1 || len - j > max_size) {
  77                                 /* Next block is the next frame. */
  78                                 control_block->next =
  79 -                                       d->control_block_base_phys +
  80 -                                       sizeof(struct bcm2835_dma_cb) *
  81 -                                       (i + split_cnt + 1);
  82 +                                       d->cb_list[i + split_cnt + 1].paddr;
  83                         } else {
  84                                 /* Next block is empty. */
  85                                 control_block->next = 0;