iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

hwrng: xgene - Simplify using devm_clk_get_optional_enabled()

Browse Source 
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@pengutronix.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Uwe Kleine-König 2023-02-14 17:28:28 +01:00 committed by Herbert Xu
parent 11f92a1308
commit 67fb1e2958
1 changed files with 6 additions and 21 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

27
drivers/char/hw_random/xgene-rng.c
View File

@ -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;
}