@@ -111,17 +111,11 @@ static int imx_rngc_self_test(struct imx_rngc *rngc)
writel(cmd | RNGC_CMD_SELF_TEST, rngc->base + RNGC_COMMAND);
ret = wait_for_completion_timeout(&rngc->rng_op_done, RNGC_TIMEOUT);
- if (!ret) {
- imx_rngc_irq_mask_clear(rngc);
+ imx_rngc_irq_mask_clear(rngc);
+ if (!ret)
return -ETIMEDOUT;
- }
-
- if (rngc->err_reg != 0) {
- imx_rngc_irq_mask_clear(rngc);
- return -EIO;
- }
- return 0;
+ return rngc->err_reg ? -EIO : 0;
}
static int imx_rngc_read(struct hwrng *rng, void *data, size_t max, bool wait)
@@ -185,10 +179,10 @@ static int imx_rngc_init(struct hwrng *rng)
cmd = readl(rngc->base + RNGC_COMMAND);
writel(cmd | RNGC_CMD_CLR_ERR, rngc->base + RNGC_COMMAND);
+ imx_rngc_irq_unmask(rngc);
+
/* create seed, repeat while there is some statistical error */
do {
- imx_rngc_irq_unmask(rngc);
-
/* seed creation */
cmd = readl(rngc->base + RNGC_COMMAND);
writel(cmd | RNGC_CMD_SEED, rngc->base + RNGC_COMMAND);
@@ -197,14 +191,16 @@ static int imx_rngc_init(struct hwrng *rng)
RNGC_TIMEOUT);
if (!ret) {
- imx_rngc_irq_mask_clear(rngc);
- return -ETIMEDOUT;
+ ret = -ETIMEDOUT;
+ goto err;
}
} while (rngc->err_reg == RNGC_ERROR_STATUS_STAT_ERR);
- if (rngc->err_reg)
- return -EIO;
+ if (rngc->err_reg) {
+ ret = -EIO;
+ goto err;
+ }
/*
* enable automatic seeding, the rngc creates a new seed automatically
@@ -214,7 +210,23 @@ static int imx_rngc_init(struct hwrng *rng)
ctrl |= RNGC_CTRL_AUTO_SEED;
writel(ctrl, rngc->base + RNGC_CONTROL);
+ /*
+ * if initialisation was successful, we keep the interrupt
+ * unmasked until imx_rngc_cleanup is called
+ * we mask the interrupt ourselves if we return an error
+ */
return 0;
+
+err:
+ imx_rngc_irq_mask_clear(rngc);
+ return ret;
+}
+
+static void imx_rngc_cleanup(struct hwrng *rng)
+{
+ struct imx_rngc *rngc = container_of(rng, struct imx_rngc, rng);
+
+ imx_rngc_irq_mask_clear(rngc);
}
static int imx_rngc_probe(struct platform_device *pdev)
@@ -272,6 +284,7 @@ static int imx_rngc_probe(struct platform_device *pdev)
rngc->rng.name = pdev->name;
rngc->rng.init = imx_rngc_init;
rngc->rng.read = imx_rngc_read;
+ rngc->rng.cleanup = imx_rngc_cleanup;
rngc->dev = &pdev->dev;
platform_set_drvdata(pdev, rngc);
Use a simpler approach for masking / unmasking the rngc interrupt: The interrupt is unmasked while self-test is running and when the rngc driver is used by the hwrng core. Mask the interrupt again when self test is finished, regardless of self test success or failure. Unmask the interrupt in the init function. Add a cleanup function where the rngc interrupt is masked again. Signed-off-by: Martin Kaiser <martin@kaiser.cx> --- drivers/char/hw_random/imx-rngc.c | 43 ++++++++++++++++++++----------- 1 file changed, 28 insertions(+), 15 deletions(-)