[PATCH 2/6 v2] crypto:s5p-sss: Add device tree support

Naveen Krishna Chatradhi
2014-01-09T04:58:45Z

This patch adds device tree support to the s5p-sss.c crypto driver.
Implements a varient struct to address the changes in SSS hardware
on various SoCs from Samsung.

Also, Documentation under devicetree/bindings added.

Signed-off-by: Naveen Krishna Ch <ch.naveen@samsung.com>
CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: David S. Miller <davem@davemloft.net>
CC: Vladimir Zapolskiy <vzapolskiy@gmail.com>
TO: <linux-crypto@vger.kernel.org>
CC: <linux-samsung-soc@vger.kernel.org>
---
Changes since v1:
1. Added description of the SSS module in Documentation
2. Corrected the interrupts description
3. Added varient struct instead of the version variable

.../devicetree/bindings/crypto/samsung-sss.txt | 20 +++++
drivers/crypto/s5p-sss.c | 81 ++++++++++++++++++--
2 files changed, 95 insertions(+), 6 deletions(-)
create mode 100644 Documentation/devicetree/bindings/crypto/samsung-sss.txt

diff --git a/Documentation/devicetree/bindings/crypto/samsung-sss.txt b/Documentation/devicetree/bindings/crypto/samsung-sss.txt
new file mode 100644
index 0000000..0e45b0d
--- /dev/null
+++ b/Documentation/devicetree/bindings/crypto/samsung-sss.txt
@@ -0,0 +1,20 @@
+Samsung SoC SSS (Security SubSystem) module
+
+The SSS module in S5PV210 SoC supports the following:
+-- Feeder (FeedCtrl)
+-- Advanced Encryption Standard (AES)
+-- Data Encryption Standard (DES)/3DES
+-- Public Key Accelerator (PKA)
+-- SHA-1/SHA-256/MD5/HMAC (SHA-1/SHA-256/MD5)/PRNG
+-- PRNG: Pseudo Random Number Generator
+
+Required properties:
+
+- compatible : Should contain entries for this and backward compatible
+ SSS versions:
+ - "samsung,s5p-secss" for S5PV210 SoC.
+- reg : Offset and length of the register set for the module
+- interrupts : the interrupt-specifier for the SSS module.
+ Two interrupts "feed control and hash" in case of S5PV210
+- clocks : the required gating clock for the SSS module.
+- clock-names : the gating clock name to be requested in the SSS driver.
diff --git a/drivers/crypto/s5p-sss.c b/drivers/crypto/s5p-sss.c
index 93cddeb..78e0c37 100644
--- a/drivers/crypto/s5p-sss.c
+++ b/drivers/crypto/s5p-sss.c
@@ -22,6 +22,7 @@
#include <linux/scatterlist.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
+#include <linux/of.h>
#include <linux/crypto.h>
#include <linux/interrupt.h>

@@ -145,6 +146,20 @@
#define AES_KEY_LEN 16
#define CRYPTO_QUEUE_LEN 1

+/**
+ * struct samsung_aes_varient - platform specific SSS driver data
+ * @has_hash_irq: true if SSS module uses hash interrupt, false otherwise
+ * @aes_offset: AES register offset from SSS module's base.
+ *
+ * Specifies platform specific configuration of SSS module.
+ * Note: A structure for driver specific platform data is used for future
+ * expansion of its usage.
+ */
+struct samsung_aes_varient {
+ bool has_hash_irq;
+ unsigned int aes_offset;
+};
+
struct s5p_aes_reqctx {
unsigned long mode;
};
@@ -173,10 +188,56 @@ struct s5p_aes_dev {
struct crypto_queue queue;
bool busy;
spinlock_t lock;
+
+ struct samsung_aes_varient *varient;
};

static struct s5p_aes_dev *s5p_dev;

+static struct samsung_aes_varient s5p_aes_data = {
+ .has_hash_irq = true,
+ .aes_offset = 0x4000,
+};
+
+static const struct platform_device_id s5p_sss_ids[] = {
+ {
+ .name = "s5p-secss",
+ .driver_data = (kernel_ulong_t)&s5p_aes_data,
+ },
+ { },
+};
+MODULE_DEVICE_TABLE(platform, s5p_sss_ids);
+
+#ifdef CONFIG_OF
+static const struct of_device_id s5p_sss_dt_match[] = {
+ {
+ .compatible = "samsung,s5p-secss",
+ .data = (void *)&s5p_aes_data,
+ },
+ { },
+};
+MODULE_DEVICE_TABLE(of, s5p_sss_dt_match);
+#else
+static struct of_device_id s5p_sss_dt_match[] = {
+ { },
+};
+#endif
+
+static inline struct samsung_aes_varient *find_s5p_sss_version
+ (struct platform_device *pdev)
+{
+ if (IS_ENABLED(CONFIG_OF)) {
+ if (pdev->dev.of_node) {
+ const struct of_device_id *match;
+ match = of_match_node(s5p_sss_dt_match,
+ pdev->dev.of_node);
+ return (struct samsung_aes_varient *)match->data;
+ }
+ }
+ return (struct samsung_aes_varient *)
+ platform_get_device_id(pdev)->driver_data;
+}
+
static void s5p_set_dma_indata(struct s5p_aes_dev *dev, struct scatterlist *sg)
{
SSS_WRITE(dev, FCBRDMAS, sg_dma_address(sg));
@@ -564,6 +625,7 @@ static int s5p_aes_probe(struct platform_device *pdev)
struct s5p_aes_dev *pdata;
struct device *dev = &pdev->dev;
struct resource *res;
+ struct samsung_aes_varient *varient;

if (s5p_dev)
return -EEXIST;
@@ -580,6 +642,8 @@ static int s5p_aes_probe(struct platform_device *pdev)
resource_size(res), pdev->name))
return -EBUSY;

+ varient = find_s5p_sss_version(pdev);
+
pdata->clk = devm_clk_get(dev, "secss");
if (IS_ERR(pdata->clk)) {
dev_err(dev, "failed to find secss clock source\n");
@@ -606,18 +670,21 @@ static int s5p_aes_probe(struct platform_device *pdev)
}

pdata->irq_hash = platform_get_irq(pdev, 1);
- if (pdata->irq_hash < 0) {
+ if (varient->has_hash_irq && pdata->irq_hash < 0) {
err = pdata->irq_hash;
dev_warn(dev, "hash interrupt is not available.\n");
goto err_irq;
}
- err = devm_request_irq(dev, pdata->irq_hash, s5p_aes_interrupt,
- IRQF_SHARED, pdev->name, pdev);
- if (err < 0) {
- dev_warn(dev, "hash interrupt is not available.\n");
- goto err_irq;
+ if (varient->has_hash_irq) {
+ err = devm_request_irq(dev, pdata->irq_hash, s5p_aes_interrupt,
+ IRQF_SHARED, pdev->name, pdev);
+ if (err < 0) {
+ dev_warn(dev, "hash interrupt is not available.\n");
+ goto err_irq;
+ }
}

+ pdata->varient = varient;
pdata->dev = dev;
platform_set_drvdata(pdev, pdata);
s5p_dev = pdata;
@@ -674,9 +741,11 @@ static int s5p_aes_remove(struct platform_device *pdev)
static struct platform_driver s5p_aes_crypto = {
.probe = s5p_aes_probe,
.remove = s5p_aes_remove,
+ .id_table = s5p_sss_ids,
.driver = {
.owner = THIS_MODULE,
.name = "s5p-secss",
+ .of_match_table = s5p_sss_dt_match,
},
};

--
1.7.9.5