Instead of setting up a kernel pointer to track the current PIO address,
track the offset in the current page, and do an atomic kmap for the page
while doing the actual PIO operations.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/mmc/host/omap.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)
diff --git a/drivers/mmc/host/omap.c b/drivers/mmc/host/omap.c
index c60a7625b1fa..0377ac6194a0 100644
--- a/drivers/mmc/host/omap.c
+++ b/drivers/mmc/host/omap.c
@@ -13,6 +13,7 @@
#include <linux/module.h>
#include <linux/moduleparam.h>
+#include <linux/highmem.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/platform_device.h>
@@ -148,7 +149,7 @@ struct mmc_omap_host {
unsigned int sg_len;
int sg_idx;
- u16 * buffer;
+ u32 buffer_offset;
u32 buffer_bytes_left;
u32 total_bytes_left;
@@ -649,7 +650,7 @@ mmc_omap_sg_to_buf(struct mmc_omap_host *host)
sg = host->data->sg + host->sg_idx;
host->buffer_bytes_left = sg->length;
- host->buffer = sg_virt(sg);
+ host->buffer_offset = sg->offset;
if (host->buffer_bytes_left > host->total_bytes_left)
host->buffer_bytes_left = host->total_bytes_left;
}
@@ -666,7 +667,9 @@ 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;
int n, nwords;
+ void *p;
if (host->buffer_bytes_left == 0) {
host->sg_idx++;
@@ -684,15 +687,17 @@ mmc_omap_xfer_data(struct mmc_omap_host *host, int write)
host->total_bytes_left -= n;
host->data->bytes_xfered += n;
+ p = kmap_atomic(sg_page(sg));
if (write) {
__raw_writesw(host->virt_base + OMAP_MMC_REG(host, DATA),
- host->buffer, nwords);
+ p + host->buffer_offset, nwords);
} else {
__raw_readsw(host->virt_base + OMAP_MMC_REG(host, DATA),
- host->buffer, nwords);
+ p + host->buffer_offset, nwords);
}
+ kunmap_atomic(p);
- host->buffer += nwords;
+ host->buffer_offset += nwords;
}
#ifdef CONFIG_MMC_DEBUG
--
2.20.1
