crypto: omap-aes - PIO mode: platform data for OMAP4/AM437x and trigger

We initialize the scatter gather walk lists needed for PIO mode and avoid all
DMA paths such as mapping/unmapping buffers by checking for the pio_only flag.

Signed-off-by: Joel Fernandes <joelf@ti.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 30 insertions, 13 deletions

diff --git a/drivers/crypto/omap-aes.c b/drivers/crypto/omap-aes.c
index 9909f93255b4..685535e4c78d 100644
--- a/drivers/crypto/omap-aes.c
+++ b/drivers/crypto/omap-aes.c
@@ -169,6 +169,7 @@ struct omap_aes_dev {
         struct dma_chan         *dma_lch_out;
         int                     in_sg_len;
         int                     out_sg_len;
+        int                     pio_only;
         const struct omap_aes_pdata     *pdata;
 };
 
@@ -408,6 +409,16 @@ static int omap_aes_crypt_dma(struct crypto_tfm *tfm,
         struct dma_slave_config cfg;
         int ret;
 
+        if (dd->pio_only) {
+                scatterwalk_start(&dd->in_walk, dd->in_sg);
+                scatterwalk_start(&dd->out_walk, dd->out_sg);
+
+                /* Enable DATAIN interrupt and let it take
+                   care of the rest */
+                omap_aes_write(dd, AES_REG_IRQ_ENABLE(dd), 0x2);
+                return 0;
+        }
+
         dma_sync_sg_for_device(dd->dev, dd->in_sg, in_sg_len, DMA_TO_DEVICE);
 
         memset(&cfg, 0, sizeof(cfg));
@@ -477,21 +488,25 @@ static int omap_aes_crypt_dma_start(struct omap_aes_dev *dd)
 
         pr_debug("total: %d\n", dd->total);
 
-        err = dma_map_sg(dd->dev, dd->in_sg, dd->in_sg_len, DMA_TO_DEVICE);
-        if (!err) {
-                dev_err(dd->dev, "dma_map_sg() error\n");
-                return -EINVAL;
-        }
+        if (!dd->pio_only) {
+                err = dma_map_sg(dd->dev, dd->in_sg, dd->in_sg_len,
+                                 DMA_TO_DEVICE);
+                if (!err) {
+                        dev_err(dd->dev, "dma_map_sg() error\n");
+                        return -EINVAL;
+                }
 
-        err = dma_map_sg(dd->dev, dd->out_sg, dd->out_sg_len, DMA_FROM_DEVICE);
-        if (!err) {
-                dev_err(dd->dev, "dma_map_sg() error\n");
-                return -EINVAL;
+                err = dma_map_sg(dd->dev, dd->out_sg, dd->out_sg_len,
+                                 DMA_FROM_DEVICE);
+                if (!err) {
+                        dev_err(dd->dev, "dma_map_sg() error\n");
+                        return -EINVAL;
+                }
         }
 
         err = omap_aes_crypt_dma(tfm, dd->in_sg, dd->out_sg, dd->in_sg_len,
                                  dd->out_sg_len);
-        if (err) {
+        if (err && !dd->pio_only) {
                 dma_unmap_sg(dd->dev, dd->in_sg, dd->in_sg_len, DMA_TO_DEVICE);
                 dma_unmap_sg(dd->dev, dd->out_sg, dd->out_sg_len,
                              DMA_FROM_DEVICE);
@@ -594,9 +609,11 @@ static void omap_aes_done_task(unsigned long data)
 
         pr_debug("enter done_task\n");
 
-        dma_sync_sg_for_cpu(dd->dev, dd->in_sg, dd->in_sg_len, DMA_FROM_DEVICE);
-
-        omap_aes_crypt_dma_stop(dd);
+        if (!dd->pio_only) {
+                dma_sync_sg_for_device(dd->dev, dd->out_sg, dd->out_sg_len,
+                                       DMA_FROM_DEVICE);
+                omap_aes_crypt_dma_stop(dd);
+        }
         omap_aes_finish_req(dd, 0);
         omap_aes_handle_queue(dd, NULL);