diff mbox series

[v4] cpufreq: s5pv210: Defer probe if getting regulators fail

Message ID 20190113195754.30525-1-pawel.mikolaj.chmiel@gmail.com (mailing list archive)
State Mainlined
Delegated to: viresh kumar
Headers show
Series [v4] cpufreq: s5pv210: Defer probe if getting regulators fail | expand

Commit Message

Paweł Chmiel Jan. 13, 2019, 7:57 p.m. UTC
There is possibility, that when probing driver, regulators are not yet
initialized. In this case we should return EPROBE_DEFER and wait till
they're initialized, since they're required currently for cpufreq driver
to work. Also move regulator initialization code at beginning of probe,
so we can defer as fast as posibble.

Signed-off-by: Paweł Chmiel <pawel.mikolaj.chmiel@gmail.com>
---
Changes from v3:
  - Zero dmc_base pointers after unmapping them
  - If getting vddarm regulator fails just return, no need to do goto
    jump which would do the same

Changes from v2:
  - Handle all error paths in probe

Changes from v1:
  - Fix compilation error
  - Reorganize code so it's smaller
---
 drivers/cpufreq/s5pv210-cpufreq.c | 67 ++++++++++++++++++++++---------
 1 file changed, 48 insertions(+), 19 deletions(-)

Comments

Krzysztof Kozlowski Jan. 14, 2019, 7:51 a.m. UTC | #1
On Sun, 13 Jan 2019 at 20:58, Paweł Chmiel
<pawel.mikolaj.chmiel@gmail.com> wrote:
>
> There is possibility, that when probing driver, regulators are not yet
> initialized. In this case we should return EPROBE_DEFER and wait till
> they're initialized, since they're required currently for cpufreq driver
> to work. Also move regulator initialization code at beginning of probe,
> so we can defer as fast as posibble.
>
> Signed-off-by: Paweł Chmiel <pawel.mikolaj.chmiel@gmail.com>
> ---
> Changes from v3:
>   - Zero dmc_base pointers after unmapping them
>   - If getting vddarm regulator fails just return, no need to do goto
>     jump which would do the same
>
> Changes from v2:
>   - Handle all error paths in probe
>
> Changes from v1:
>   - Fix compilation error
>   - Reorganize code so it's smaller

Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>

Best regards,
Krzysztof
Viresh Kumar Jan. 18, 2019, 5:10 a.m. UTC | #2
On 14-01-19, 08:51, Krzysztof Kozlowski wrote:
> On Sun, 13 Jan 2019 at 20:58, Paweł Chmiel
> <pawel.mikolaj.chmiel@gmail.com> wrote:
> >
> > There is possibility, that when probing driver, regulators are not yet
> > initialized. In this case we should return EPROBE_DEFER and wait till
> > they're initialized, since they're required currently for cpufreq driver
> > to work. Also move regulator initialization code at beginning of probe,
> > so we can defer as fast as posibble.
> >
> > Signed-off-by: Paweł Chmiel <pawel.mikolaj.chmiel@gmail.com>
> > ---
> > Changes from v3:
> >   - Zero dmc_base pointers after unmapping them
> >   - If getting vddarm regulator fails just return, no need to do goto
> >     jump which would do the same
> >
> > Changes from v2:
> >   - Handle all error paths in probe
> >
> > Changes from v1:
> >   - Fix compilation error
> >   - Reorganize code so it's smaller
> 
> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>

Applied, thanks.
diff mbox series

Patch

diff --git a/drivers/cpufreq/s5pv210-cpufreq.c b/drivers/cpufreq/s5pv210-cpufreq.c
index f51697f1e0b3..c7b7d1e65b08 100644
--- a/drivers/cpufreq/s5pv210-cpufreq.c
+++ b/drivers/cpufreq/s5pv210-cpufreq.c
@@ -584,7 +584,7 @@  static struct notifier_block s5pv210_cpufreq_reboot_notifier = {
 static int s5pv210_cpufreq_probe(struct platform_device *pdev)
 {
 	struct device_node *np;
-	int id;
+	int id, result = 0;
 
 	/*
 	 * HACK: This is a temporary workaround to get access to clock
@@ -594,18 +594,39 @@  static int s5pv210_cpufreq_probe(struct platform_device *pdev)
 	 * this whole driver as soon as S5PV210 gets migrated to use
 	 * cpufreq-dt driver.
 	 */
+	arm_regulator = regulator_get(NULL, "vddarm");
+	if (IS_ERR(arm_regulator)) {
+		if (PTR_ERR(arm_regulator) == -EPROBE_DEFER)
+			pr_debug("vddarm regulator not ready, defer\n");
+		else
+			pr_err("failed to get regulator vddarm\n");
+		return PTR_ERR(arm_regulator);
+	}
+
+	int_regulator = regulator_get(NULL, "vddint");
+	if (IS_ERR(int_regulator)) {
+		if (PTR_ERR(int_regulator) == -EPROBE_DEFER)
+			pr_debug("vddint regulator not ready, defer\n");
+		else
+			pr_err("failed to get regulator vddint\n");
+		result = PTR_ERR(int_regulator);
+		goto err_int_regulator;
+	}
+
 	np = of_find_compatible_node(NULL, NULL, "samsung,s5pv210-clock");
 	if (!np) {
 		pr_err("%s: failed to find clock controller DT node\n",
 			__func__);
-		return -ENODEV;
+		result = -ENODEV;
+		goto err_clock;
 	}
 
 	clk_base = of_iomap(np, 0);
 	of_node_put(np);
 	if (!clk_base) {
 		pr_err("%s: failed to map clock registers\n", __func__);
-		return -EFAULT;
+		result = -EFAULT;
+		goto err_clock;
 	}
 
 	for_each_compatible_node(np, NULL, "samsung,s5pv210-dmc") {
@@ -614,7 +635,8 @@  static int s5pv210_cpufreq_probe(struct platform_device *pdev)
 			pr_err("%s: failed to get alias of dmc node '%pOFn'\n",
 				__func__, np);
 			of_node_put(np);
-			return id;
+			result = id;
+			goto err_clk_base;
 		}
 
 		dmc_base[id] = of_iomap(np, 0);
@@ -622,33 +644,40 @@  static int s5pv210_cpufreq_probe(struct platform_device *pdev)
 			pr_err("%s: failed to map dmc%d registers\n",
 				__func__, id);
 			of_node_put(np);
-			return -EFAULT;
+			result = -EFAULT;
+			goto err_dmc;
 		}
 	}
 
 	for (id = 0; id < ARRAY_SIZE(dmc_base); ++id) {
 		if (!dmc_base[id]) {
 			pr_err("%s: failed to find dmc%d node\n", __func__, id);
-			return -ENODEV;
+			result = -ENODEV;
+			goto err_dmc;
 		}
 	}
 
-	arm_regulator = regulator_get(NULL, "vddarm");
-	if (IS_ERR(arm_regulator)) {
-		pr_err("failed to get regulator vddarm\n");
-		return PTR_ERR(arm_regulator);
-	}
-
-	int_regulator = regulator_get(NULL, "vddint");
-	if (IS_ERR(int_regulator)) {
-		pr_err("failed to get regulator vddint\n");
-		regulator_put(arm_regulator);
-		return PTR_ERR(int_regulator);
-	}
-
 	register_reboot_notifier(&s5pv210_cpufreq_reboot_notifier);
 
 	return cpufreq_register_driver(&s5pv210_driver);
+
+err_dmc:
+	for (id = 0; id < ARRAY_SIZE(dmc_base); ++id)
+		if (dmc_base[id]) {
+			iounmap(dmc_base[id]);
+			dmc_base[id] = NULL;
+		}
+
+err_clk_base:
+	iounmap(clk_base);
+
+err_clock:
+	regulator_put(int_regulator);
+
+err_int_regulator:
+	regulator_put(arm_regulator);
+
+	return result;
 }
 
 static struct platform_driver s5pv210_cpufreq_platdrv = {