Instead of ignoring errors returned by devm_clk_get() and manually
enabling the clk for the whole lifetime of the bound device, use
devm_clk_get_optional_enabled(). This is simpler and also more correct
as it doesn't ignore errors. This is also more correct because now the
call to clk_disable_unprepare() can be dropped from xgene_rng_remove()
which happened while the hwrn device was still registered. With the devm
callback disabling the clk happens correctly only after
devm_hwrng_register() is undone.
As a result struct xgene_rng_dev::clk is only used in xgene_rng_probe, and
so the struct member can be replaced by a local variable.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
---
drivers/char/hw_random/xgene-rng.c | 27 ++++++---------------------
1 file changed, 6 insertions(+), 21 deletions(-)
diff --git a/drivers/char/hw_random/xgene-rng.c b/drivers/char/hw_random/xgene-rng.c
index a6a30686a58b..31662614a48f 100644
--- a/drivers/char/hw_random/xgene-rng.c
+++ b/drivers/char/hw_random/xgene-rng.c
@@ -84,7 +84,6 @@ struct xgene_rng_dev {
unsigned long failure_ts;/* First failure timestamp */
struct timer_list failure_timer;
struct device *dev;
- struct clk *clk;
};
static void xgene_rng_expired_timer(struct timer_list *t)
@@ -314,6 +313,7 @@ static struct hwrng xgene_rng_func = {
static int xgene_rng_probe(struct platform_device *pdev)
{
struct xgene_rng_dev *ctx;
+ struct clk *clk;
int rc = 0;
ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
@@ -341,45 +341,30 @@ static int xgene_rng_probe(struct platform_device *pdev)
return dev_err_probe(&pdev->dev, rc, "Could not request RNG alarm IRQ\n");
/* Enable IP clock */
- ctx->clk = devm_clk_get(&pdev->dev, NULL);
- if (IS_ERR(ctx->clk)) {
- dev_warn(&pdev->dev, "Couldn't get the clock for RNG\n");
- } else {
- rc = clk_prepare_enable(ctx->clk);
- if (rc)
- return dev_err_probe(&pdev->dev, rc,
- "clock prepare enable failed for RNG");
- }
+ clk = devm_clk_get_optional_enabled(&pdev->dev, NULL);
+ if (IS_ERR(clk))
+ return dev_err_probe(&pdev->dev, PTR_ERR(clk), "Couldn't get the clock for RNG\n");
xgene_rng_func.priv = (unsigned long) ctx;
rc = devm_hwrng_register(&pdev->dev, &xgene_rng_func);
- if (rc) {
- if (!IS_ERR(ctx->clk))
- clk_disable_unprepare(ctx->clk);
+ if (rc)
return dev_err_probe(&pdev->dev, rc, "RNG registering failed\n");
- }
rc = device_init_wakeup(&pdev->dev, 1);
- if (rc) {
- if (!IS_ERR(ctx->clk))
- clk_disable_unprepare(ctx->clk);
+ if (rc)
return dev_err_probe(&pdev->dev, rc, "RNG device_init_wakeup failed\n");
- }
return 0;
}
static int xgene_rng_remove(struct platform_device *pdev)
{
- struct xgene_rng_dev *ctx = platform_get_drvdata(pdev);
int rc;
rc = device_init_wakeup(&pdev->dev, 0);
if (rc)
dev_err(&pdev->dev, "RNG init wakeup failed error %d\n", rc);
- if (!IS_ERR(ctx->clk))
- clk_disable_unprepare(ctx->clk);
return rc;
}
--
2.39.1
