[PATCH 9/9] crypto: atmel-ecc: Break out lock check helper

[Linus Walleij]

This breaks out a lock status checker to be used with further
refactorings.

Signed-off-by: Linus Walleij <linus.wall...@linaro.org>
---
 drivers/crypto/atmel-ecc.c | 38 ++++++++++++++++++++++++++++++++++----
 1 file changed, 34 insertions(+), 4 deletions(-)

diff --git a/drivers/crypto/atmel-ecc.c b/drivers/crypto/atmel-ecc.c
index 2b6c8bb7bd1c..d15cc77ab739 100644
--- a/drivers/crypto/atmel-ecc.c
+++ b/drivers/crypto/atmel-ecc.c
@@ -668,7 +668,9 @@ static int atmel_ecc_get_serial(struct i2c_client *client)
        return 0;
 }
 
-static int device_sanity_check(struct i2c_client *client)
+static int atmel_ecc_get_lock_status(struct i2c_client *client,
+                                    bool *config_is_locked,
+                                    bool *otp_data_is_locked)
 {
        struct atmel_ecc_cmd *cmd;
        int ret;
@@ -682,21 +684,49 @@ static int device_sanity_check(struct i2c_client *client)
        ret = atmel_ecc_send_receive(client, cmd);
        if (ret) {
                dev_err(&client->dev,
-                       "failed to send ECC init command\n");
+                       "failed to send config read command\n");
                goto free_cmd;
        }
 
+       /* According to datasheet anything else than 0x55 means "locked" */
+       if (cmd->data[RSP_DATA_IDX+3] == 0x55)
+               *config_is_locked = false;
+       else
+               *config_is_locked = true;
+
+       if (cmd->data[RSP_DATA_IDX+2] == 0x55)
+               *otp_data_is_locked = false;
+       else
+               *otp_data_is_locked = true;
+
+free_cmd:
+       kfree(cmd);
+       return ret;
+}
+
+static int device_sanity_check(struct i2c_client *client)
+{
+       struct atmel_ecc_cmd *cmd;
+       bool config_locked;
+       bool otp_data_locked;
+       int ret;
+
        /*
         * It is vital that the Configuration, Data and OTP zones be locked
         * prior to release into the field of the system containing the device.
         * Failure to lock these zones may permit modification of any secret
         * keys and may lead to other security problems.
         */
-       if (cmd->data[RSP_DATA_IDX+3] == 0x55) {
+       ret = atmel_ecc_get_lock_status(client, &config_locked,
+                                       &otp_data_locked);
+       if (ret)
+               return ret;
+
+       if (!config_locked) {
                dev_err(&client->dev, "configuration zone is unlocked\n");
                ret = -ENOTSUPP;
        }
-       if (cmd->data[RSP_DATA_IDX+2] == 0x55) {
+       if (!otp_data_locked) {
                dev_err(&client->dev, "data and OTP zones are unlocked\n");
                ret = -ENOTSUPP;
        }
-- 
2.17.0