[PATCH 07/14] mmc: omap: handle chained sglists

From: Christoph Hellwig
Date: Tue Feb 12 2019 - 02:26:52 EST


Use the proper sg_next() helper to move to the next scatterlist element
to support chained scatterlists.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/mmc/host/omap.c | 16 ++++++----------
1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/mmc/host/omap.c b/drivers/mmc/host/omap.c
index 6741c95f2281..8cd39bc087fa 100644
--- a/drivers/mmc/host/omap.c
+++ b/drivers/mmc/host/omap.c
@@ -147,7 +147,7 @@ struct mmc_omap_host {
struct mmc_data *stop_data;

unsigned int sg_len;
- int sg_idx;
+ struct scatterlist *cur_sg;
u32 buffer_offset;
u32 buffer_bytes_left;
u32 total_bytes_left;
@@ -645,11 +645,8 @@ mmc_omap_cmd_timer(struct timer_list *t)
static void
mmc_omap_sg_to_buf(struct mmc_omap_host *host)
{
- struct scatterlist *sg;
-
- sg = host->data->sg + host->sg_idx;
- host->buffer_bytes_left = sg->length;
- host->buffer_offset = sg->offset;
+ host->buffer_bytes_left = host->cur_sg->length;
+ host->buffer_offset = host->cur_sg->offset;
if (host->buffer_bytes_left > host->total_bytes_left)
host->buffer_bytes_left = host->total_bytes_left;
}
@@ -666,13 +663,12 @@ mmc_omap_clk_timer(struct timer_list *t)
static void
mmc_omap_xfer_data(struct mmc_omap_host *host, int write)
{
- struct scatterlist *sg = host->data->sg + host->sg_idx;
+ struct scatterlist *sg = host->cur_sg;
int n, nwords;
void *p;

if (host->buffer_bytes_left == 0) {
- host->sg_idx++;
- BUG_ON(host->sg_idx == host->sg_len);
+ host->cur_sg = sg_next(host->cur_sg);
mmc_omap_sg_to_buf(host);
}
n = 64;
@@ -984,7 +980,7 @@ mmc_omap_prepare_data(struct mmc_omap_host *host, struct mmc_request *req)
}
}

- host->sg_idx = 0;
+ host->cur_sg = host->data->sg;
if (use_dma) {
enum dma_data_direction dma_data_dir;
struct dma_async_tx_descriptor *tx;
--
2.20.1