2020-04-27 06:45:14

by Lionel Debieve

[permalink] [raw]
Subject: [PATCH 2/3] crypto: stm32/hash - defer probe for dma device

From: Etienne Carriere <[email protected]>

Change stm32 HASH driver to defer its probe operation when
DMA channel device is registered but has not been probed yet.

Signed-off-by: Etienne Carriere <[email protected]>
Reviewed-by: Lionel DEBIEVE <[email protected]>
---
drivers/crypto/stm32/stm32-hash.c | 22 +++++++++++++++-------
1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/drivers/crypto/stm32/stm32-hash.c b/drivers/crypto/stm32/stm32-hash.c
index fad6190be088..0d592f55a271 100644
--- a/drivers/crypto/stm32/stm32-hash.c
+++ b/drivers/crypto/stm32/stm32-hash.c
@@ -507,6 +507,7 @@ static int stm32_hash_hmac_dma_send(struct stm32_hash_dev *hdev)
static int stm32_hash_dma_init(struct stm32_hash_dev *hdev)
{
struct dma_slave_config dma_conf;
+ struct dma_chan *chan;
int err;

memset(&dma_conf, 0, sizeof(dma_conf));
@@ -518,11 +519,11 @@ static int stm32_hash_dma_init(struct stm32_hash_dev *hdev)
dma_conf.dst_maxburst = hdev->dma_maxburst;
dma_conf.device_fc = false;

- hdev->dma_lch = dma_request_chan(hdev->dev, "in");
- if (IS_ERR(hdev->dma_lch)) {
- dev_err(hdev->dev, "Couldn't acquire a slave DMA channel.\n");
- return PTR_ERR(hdev->dma_lch);
- }
+ chan = dma_request_chan(hdev->dev, "in");
+ if (IS_ERR(chan))
+ return PTR_ERR(chan);
+
+ hdev->dma_lch = chan;

err = dmaengine_slave_config(hdev->dma_lch, &dma_conf);
if (err) {
@@ -1498,8 +1499,15 @@ static int stm32_hash_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, hdev);

ret = stm32_hash_dma_init(hdev);
- if (ret)
+ switch (ret) {
+ case 0:
+ break;
+ case -ENOENT:
dev_dbg(dev, "DMA mode not available\n");
+ break;
+ default:
+ goto err_dma;
+ }

spin_lock(&stm32_hash.lock);
list_add_tail(&hdev->list, &stm32_hash.dev_list);
@@ -1537,7 +1545,7 @@ static int stm32_hash_probe(struct platform_device *pdev)
spin_lock(&stm32_hash.lock);
list_del(&hdev->list);
spin_unlock(&stm32_hash.lock);
-
+err_dma:
if (hdev->dma_lch)
dma_release_channel(hdev->dma_lch);
err_reset:
--
2.17.1