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

[Leonard Crestez]

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.cres...@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