[PATCH v4 08/16] PM / devfreq: tegra: Clean up driver's probe / remove

Dmitry Osipenko
2019-05-01T23:42:09Z

Reset hardware, disable ACTMON clock, release OPP's and handle all
possible error cases correctly, maintaining the correct tear down
order. Also use devm_platform_ioremap_resource() which is now available
in the kernel.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
drivers/devfreq/tegra-devfreq.c | 83 +++++++++++++++++++--------------
1 file changed, 47 insertions(+), 36 deletions(-)

diff --git a/drivers/devfreq/tegra-devfreq.c b/drivers/devfreq/tegra-devfreq.c
index ce1eb97a2090..ea0da05cd7f2 100644
--- a/drivers/devfreq/tegra-devfreq.c
+++ b/drivers/devfreq/tegra-devfreq.c
@@ -610,7 +610,6 @@ static int tegra_devfreq_probe(struct platform_device *pdev)
{
struct tegra_devfreq *tegra;
struct tegra_devfreq_device *dev;
- struct resource *res;
unsigned int i;
unsigned long rate;
int err;
@@ -619,9 +618,7 @@ static int tegra_devfreq_probe(struct platform_device *pdev)
if (!tegra)
return -ENOMEM;

- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-
- tegra->regs = devm_ioremap_resource(&pdev->dev, res);
+ tegra->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(tegra->regs))
return PTR_ERR(tegra->regs);

@@ -643,11 +640,10 @@ static int tegra_devfreq_probe(struct platform_device *pdev)
return PTR_ERR(tegra->emc_clock);
}

- tegra->rate_change_nb.notifier_call = tegra_actmon_rate_notify_cb;
- err = clk_notifier_register(tegra->emc_clock, &tegra->rate_change_nb);
- if (err) {
- dev_err(&pdev->dev,
- "Failed to register rate change notifier\n");
+ tegra->irq = platform_get_irq(pdev, 0);
+ if (tegra->irq < 0) {
+ err = tegra->irq;
+ dev_err(&pdev->dev, "Failed to get IRQ: %d\n", err);
return err;
}

@@ -678,54 +674,69 @@ static int tegra_devfreq_probe(struct platform_device *pdev)

for (rate = 0; rate <= tegra->max_freq * KHZ; rate++) {
rate = clk_round_rate(tegra->emc_clock, rate);
- dev_pm_opp_add(&pdev->dev, rate, 0);
- }

- tegra->irq = platform_get_irq(pdev, 0);
- if (tegra->irq < 0) {
- err = tegra->irq;
- dev_err(&pdev->dev, "Failed to get IRQ: %d\n", err);
- return err;
+ err = dev_pm_opp_add(&pdev->dev, rate, 0);
+ if (err) {
+ dev_err(&pdev->dev, "Failed to add OPP: %d\n", err);
+ goto remove_opps;
+ }
}

platform_set_drvdata(pdev, tegra);

+ tegra->rate_change_nb.notifier_call = tegra_actmon_rate_notify_cb;
+ err = clk_notifier_register(tegra->emc_clock, &tegra->rate_change_nb);
+ if (err) {
+ dev_err(&pdev->dev,
+ "Failed to register rate change notifier\n");
+ goto remove_opps;
+ }
+
+ tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock);
+ tegra->devfreq = devfreq_add_device(&pdev->dev,
+ &tegra_devfreq_profile,
+ "tegra_actmon",
+ NULL);
+ if (IS_ERR(tegra->devfreq)) {
+ err = PTR_ERR(tegra->devfreq);
+ goto unreg_notifier;
+ }
+
err = devm_request_threaded_irq(&pdev->dev, tegra->irq, NULL,
actmon_thread_isr, IRQF_ONESHOT,
"tegra-devfreq", tegra);
if (err) {
- dev_err(&pdev->dev, "Interrupt request failed\n");
- return err;
+ dev_err(&pdev->dev, "Interrupt request failed: %d\n", err);
+ goto remove_devfreq;
}

- tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock);
- tegra->devfreq = devm_devfreq_add_device(&pdev->dev,
- &tegra_devfreq_profile,
- "tegra_actmon",
- NULL);
-
return 0;
+
+remove_devfreq:
+ devfreq_remove_device(tegra->devfreq);
+
+unreg_notifier:
+ clk_notifier_unregister(tegra->emc_clock, &tegra->rate_change_nb);
+
+remove_opps:
+ dev_pm_opp_remove_all_dynamic(&pdev->dev);
+
+ reset_control_reset(tegra->reset);
+ clk_disable_unprepare(tegra->clock);
+
+ return err;
}

static int tegra_devfreq_remove(struct platform_device *pdev)
{
struct tegra_devfreq *tegra = platform_get_drvdata(pdev);
- int irq = platform_get_irq(pdev, 0);
- u32 val;
- unsigned int i;
-
- for (i = 0; i < ARRAY_SIZE(actmon_device_configs); i++) {
- val = device_readl(&tegra->devices[i], ACTMON_DEV_CTRL);
- val &= ~ACTMON_DEV_CTRL_ENB;
- device_writel(&tegra->devices[i], val, ACTMON_DEV_CTRL);
- }
-
- actmon_write_barrier(tegra);

- devm_free_irq(&pdev->dev, irq, tegra);
+ devfreq_remove_device(tegra->devfreq);

clk_notifier_unregister(tegra->emc_clock, &tegra->rate_change_nb);
+ dev_pm_opp_remove_all_dynamic(&pdev->dev);

+ reset_control_reset(tegra->reset);
clk_disable_unprepare(tegra->clock);

return 0;
--
2.21.0