Unverified Commit 3bfd9103 authored by Ikjoon Jang's avatar Ikjoon Jang Committed by Mark Brown
Browse files

spi: spi-mtk-nor: Add power management support 



This patch adds dev_pm_ops to mtk-nor to support suspend/resume,
auto suspend delay is set to -1 by default.

Accessing registers are only permitted after its clock is enabled
to deal with unknown state of operating clk at probe time.

Signed-off-by: default avatarIkjoon Jang <ikjn@chromium.org>
Link: https://lore.kernel.org/r/20201006155010.v5.4.I68983b582d949a91866163bab588ff3c2a0d0275@changeid


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent e836d4cf

drivers/spi/spi-mtk-nor.c

+76 −22
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ 
#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/of_device.h>

#include <linux/pm_runtime.h>

#include <linux/spi/spi.h>

#include <linux/spi/spi-mem.h>

#include <linux/string.h>
@@ -690,22 +691,15 @@ static int mtk_nor_enable_clk(struct mtk_nor *sp) 
	return 0;

}



static int mtk_nor_init(struct mtk_nor *sp)

static void mtk_nor_init(struct mtk_nor *sp)

{

	int ret;



	ret = mtk_nor_enable_clk(sp);

	if (ret)

		return ret;



	sp->spi_freq = clk_get_rate(sp->spi_clk);

	writel(0, sp->base + MTK_NOR_REG_IRQ_EN);

	writel(MTK_NOR_IRQ_MASK, sp->base + MTK_NOR_REG_IRQ_STAT);



	writel(MTK_NOR_ENABLE_SF_CMD, sp->base + MTK_NOR_REG_WP);

	mtk_nor_rmw(sp, MTK_NOR_REG_CFG2, MTK_NOR_WR_CUSTOM_OP_EN, 0);

	mtk_nor_rmw(sp, MTK_NOR_REG_CFG3,

		    MTK_NOR_DISABLE_WREN | MTK_NOR_DISABLE_SR_POLL, 0);



	return ret;

}



static irqreturn_t mtk_nor_irq_handler(int irq, void *data)
@@ -788,6 +782,7 @@ static int mtk_nor_probe(struct platform_device *pdev) 
	ctlr->num_chipselect = 1;

	ctlr->setup = mtk_nor_setup;

	ctlr->transfer_one_message = mtk_nor_transfer_one_message;

	ctlr->auto_runtime_pm = true;



	dev_set_drvdata(&pdev->dev, ctlr);
@@ -811,12 +806,19 @@ static int mtk_nor_probe(struct platform_device *pdev) 
		return -ENOMEM;

	}



	ret = mtk_nor_enable_clk(sp);

	if (ret < 0)

		return ret;



	sp->spi_freq = clk_get_rate(sp->spi_clk);



	mtk_nor_init(sp);



	irq = platform_get_irq_optional(pdev, 0);



	if (irq < 0) {

		dev_warn(sp->dev, "IRQ not available.");

	} else {

		writel(MTK_NOR_IRQ_MASK, base + MTK_NOR_REG_IRQ_STAT);

		writel(0, base + MTK_NOR_REG_IRQ_EN);

		ret = devm_request_irq(sp->dev, irq, mtk_nor_irq_handler, 0,

				       pdev->name, sp);

		if (ret < 0) {
@@ -827,34 +829,86 @@ static int mtk_nor_probe(struct platform_device *pdev) 
		}

	}



	ret = mtk_nor_init(sp);

	if (ret < 0) {

		kfree(ctlr);

		return ret;

	}

	pm_runtime_set_autosuspend_delay(&pdev->dev, -1);

	pm_runtime_use_autosuspend(&pdev->dev);

	pm_runtime_set_active(&pdev->dev);

	pm_runtime_enable(&pdev->dev);

	pm_runtime_get_noresume(&pdev->dev);



	ret = devm_spi_register_controller(&pdev->dev, ctlr);

	if (ret < 0)

		goto err_probe;



	pm_runtime_mark_last_busy(&pdev->dev);

	pm_runtime_put_autosuspend(&pdev->dev);



	dev_info(&pdev->dev, "spi frequency: %d Hz\n", sp->spi_freq);



	return devm_spi_register_controller(&pdev->dev, ctlr);

	return 0;



err_probe:

	pm_runtime_disable(&pdev->dev);

	pm_runtime_set_suspended(&pdev->dev);

	pm_runtime_dont_use_autosuspend(&pdev->dev);



	mtk_nor_disable_clk(sp);



	return ret;

}



static int mtk_nor_remove(struct platform_device *pdev)

{

	struct spi_controller *ctlr;

	struct mtk_nor *sp;

	struct spi_controller *ctlr = dev_get_drvdata(&pdev->dev);

	struct mtk_nor *sp = spi_controller_get_devdata(ctlr);



	ctlr = dev_get_drvdata(&pdev->dev);

	sp = spi_controller_get_devdata(ctlr);

	pm_runtime_disable(&pdev->dev);

	pm_runtime_set_suspended(&pdev->dev);

	pm_runtime_dont_use_autosuspend(&pdev->dev);



	mtk_nor_disable_clk(sp);



	return 0;

}



static int __maybe_unused mtk_nor_runtime_suspend(struct device *dev)

{

	struct spi_controller *ctlr = dev_get_drvdata(dev);

	struct mtk_nor *sp = spi_controller_get_devdata(ctlr);



	mtk_nor_disable_clk(sp);



	return 0;

}



static int __maybe_unused mtk_nor_runtime_resume(struct device *dev)

{

	struct spi_controller *ctlr = dev_get_drvdata(dev);

	struct mtk_nor *sp = spi_controller_get_devdata(ctlr);



	return mtk_nor_enable_clk(sp);

}



static int __maybe_unused mtk_nor_suspend(struct device *dev)

{

	return pm_runtime_force_suspend(dev);

}



static int __maybe_unused mtk_nor_resume(struct device *dev)

{

	return pm_runtime_force_resume(dev);

}



static const struct dev_pm_ops mtk_nor_pm_ops = {

	SET_RUNTIME_PM_OPS(mtk_nor_runtime_suspend,

			   mtk_nor_runtime_resume, NULL)

	SET_SYSTEM_SLEEP_PM_OPS(mtk_nor_suspend, mtk_nor_resume)

};



static struct platform_driver mtk_nor_driver = {

	.driver = {

		.name = DRIVER_NAME,

		.of_match_table = mtk_nor_match,

		.pm = &mtk_nor_pm_ops,

	},

	.probe = mtk_nor_probe,

	.remove = mtk_nor_remove,

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