Commit 60630924 authored by Fabien Dessenne's avatar Fabien Dessenne Committed by Bjorn Andersson
Browse files

hwspinlock: stm32: enable clock at probe 



Set the clock during probe and keep its control during suspend / resume
operations.
This fixes an issue when CONFIG_PM is not set and where the clock is
never enabled.

Make use of devm_ functions to simplify the code.

Signed-off-by: default avatarFabien Dessenne <fabien.dessenne@foss.st.com>
Signed-off-by: default avatarBjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20211011135836.1045437-1-fabien.dessenne@foss.st.com
parent fa55b7dc

drivers/hwspinlock/stm32_hwspinlock.c

+37 −21
Original line number Diff line number Diff line
@@ -54,8 +54,23 @@ static const struct hwspinlock_ops stm32_hwspinlock_ops = { 
	.relax		= stm32_hwspinlock_relax,

};



static void stm32_hwspinlock_disable_clk(void *data)

{

	struct platform_device *pdev = data;

	struct stm32_hwspinlock *hw = platform_get_drvdata(pdev);

	struct device *dev = &pdev->dev;



	pm_runtime_get_sync(dev);

	pm_runtime_disable(dev);

	pm_runtime_set_suspended(dev);

	pm_runtime_put_noidle(dev);



	clk_disable_unprepare(hw->clk);

}



static int stm32_hwspinlock_probe(struct platform_device *pdev)

{

	struct device *dev = &pdev->dev;

	struct stm32_hwspinlock *hw;

	void __iomem *io_base;

	size_t array_size;
@@ -66,41 +81,43 @@ static int stm32_hwspinlock_probe(struct platform_device *pdev) 
		return PTR_ERR(io_base);



	array_size = STM32_MUTEX_NUM_LOCKS * sizeof(struct hwspinlock);

	hw = devm_kzalloc(&pdev->dev, sizeof(*hw) + array_size, GFP_KERNEL);

	hw = devm_kzalloc(dev, sizeof(*hw) + array_size, GFP_KERNEL);

	if (!hw)

		return -ENOMEM;



	hw->clk = devm_clk_get(&pdev->dev, "hsem");

	hw->clk = devm_clk_get(dev, "hsem");

	if (IS_ERR(hw->clk))

		return PTR_ERR(hw->clk);



	for (i = 0; i < STM32_MUTEX_NUM_LOCKS; i++)

		hw->bank.lock[i].priv = io_base + i * sizeof(u32);

	ret = clk_prepare_enable(hw->clk);

	if (ret) {

		dev_err(dev, "Failed to prepare_enable clock\n");

		return ret;

	}



	platform_set_drvdata(pdev, hw);

	pm_runtime_enable(&pdev->dev);



	ret = hwspin_lock_register(&hw->bank, &pdev->dev, &stm32_hwspinlock_ops,

				   0, STM32_MUTEX_NUM_LOCKS);



	if (ret)

		pm_runtime_disable(&pdev->dev);

	pm_runtime_get_noresume(dev);

	pm_runtime_set_active(dev);

	pm_runtime_enable(dev);

	pm_runtime_put(dev);



	ret = devm_add_action_or_reset(dev, stm32_hwspinlock_disable_clk, pdev);

	if (ret) {

		dev_err(dev, "Failed to register action\n");

		return ret;

	}



static int stm32_hwspinlock_remove(struct platform_device *pdev)

{

	struct stm32_hwspinlock *hw = platform_get_drvdata(pdev);

	int ret;

	for (i = 0; i < STM32_MUTEX_NUM_LOCKS; i++)

		hw->bank.lock[i].priv = io_base + i * sizeof(u32);



	ret = hwspin_lock_unregister(&hw->bank);

	if (ret)

		dev_err(&pdev->dev, "%s failed: %d\n", __func__, ret);

	ret = devm_hwspin_lock_register(dev, &hw->bank, &stm32_hwspinlock_ops,

					0, STM32_MUTEX_NUM_LOCKS);



	pm_runtime_disable(&pdev->dev);

	if (ret)

		dev_err(dev, "Failed to register hwspinlock\n");



	return 0;

	return ret;

}



static int __maybe_unused stm32_hwspinlock_runtime_suspend(struct device *dev)
@@ -135,7 +152,6 @@ MODULE_DEVICE_TABLE(of, stm32_hwpinlock_ids); 


static struct platform_driver stm32_hwspinlock_driver = {

	.probe		= stm32_hwspinlock_probe,

	.remove		= stm32_hwspinlock_remove,

	.driver		= {

		.name	= "stm32_hwspinlock",

		.of_match_table = stm32_hwpinlock_ids,