[PATCH v2 2/4] crypto: mxs-dcp - Add support for dcp clk

Leonard Crestez
2018-10-15T13:27:37Z

On 6ull and 6sll the DCP block has a clock which needs to be explicitly
enabled.

Add minimal handling for this at probe/remove time.

Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
---
drivers/crypto/mxs-dcp.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)

diff --git a/drivers/crypto/mxs-dcp.c b/drivers/crypto/mxs-dcp.c
index 849a81ece079..fd13787a2a0e 100644
--- a/drivers/crypto/mxs-dcp.c
+++ b/drivers/crypto/mxs-dcp.c
@@ -18,10 +18,11 @@
#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/stmp_device.h>
+#include <linux/clk.h>

#include <crypto/aes.h>
#include <crypto/sha.h>
#include <crypto/internal/hash.h>
#include <crypto/internal/skcipher.h>
@@ -80,10 +81,11 @@ struct dcp {

struct completion completion[DCP_MAX_CHANS];
spinlock_t lock[DCP_MAX_CHANS];
struct task_struct *thread[DCP_MAX_CHANS];
struct crypto_queue queue[DCP_MAX_CHANS];
+ struct clk *dcp_clk;
};

enum dcp_chan {
DCP_CHAN_HASH_SHA = 0,
DCP_CHAN_CRYPTO = 2,
@@ -1027,10 +1029,24 @@ static int mxs_dcp_probe(struct platform_device *pdev)
sdcp->dev = dev;
sdcp->base = devm_ioremap_resource(dev, iores);
if (IS_ERR(sdcp->base))
return PTR_ERR(sdcp->base);

+ /* DCP clock is optional, only used on some SOCs */
+ sdcp->dcp_clk = devm_clk_get(dev, "dcp");
+ if (IS_ERR(sdcp->dcp_clk)) {
+ if (sdcp->dcp_clk != ERR_PTR(-ENOENT))
+ return PTR_ERR(sdcp->dcp_clk);
+ sdcp->dcp_clk = NULL;
+ }
+
+ ret = clk_prepare(sdcp->dcp_clk);
+ if (ret)
+ return ret;
+ ret = clk_enable(sdcp->dcp_clk);
+ if (ret)
+ return ret;

ret = devm_request_irq(dev, dcp_vmi_irq, mxs_dcp_irq, 0,
"dcp-vmi-irq", sdcp);
if (ret) {
dev_err(dev, "Failed to claim DCP VMI IRQ!\n");
@@ -1168,10 +1184,12 @@ static int mxs_dcp_remove(struct platform_device *pdev)
crypto_unregister_algs(dcp_aes_algs, ARRAY_SIZE(dcp_aes_algs));

kthread_stop(sdcp->thread[DCP_CHAN_HASH_SHA]);
kthread_stop(sdcp->thread[DCP_CHAN_CRYPTO]);

+ clk_disable(sdcp->dcp_clk);
+
platform_set_drvdata(pdev, NULL);

global_sdcp = NULL;

return 0;
--
2.17.1