From 822c8d45a170312e368271c3c8f43d49cac863a2 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 31 Jul 2017 14:53:07 +0900 Subject: [PATCH] i2c: uniphier-f: add suspend / resume support When resuming, set up registers that have been lost in the sleep state. Also, add clock handling in the resume / suspend hooks. Signed-off-by: Masahiro Yamada Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-uniphier-f.c | 46 +++++++++++++++++++++++++++++-------- 1 file changed, 37 insertions(+), 9 deletions(-) diff --git a/drivers/i2c/busses/i2c-uniphier-f.c b/drivers/i2c/busses/i2c-uniphier-f.c index beee318..9918bdd 100644 --- a/drivers/i2c/busses/i2c-uniphier-f.c +++ b/drivers/i2c/busses/i2c-uniphier-f.c @@ -97,6 +97,7 @@ struct uniphier_fi2c_priv { int error; unsigned int flags; unsigned int busy_cnt; + unsigned int clk_cycle; }; static void uniphier_fi2c_fill_txfifo(struct uniphier_fi2c_priv *priv, @@ -461,9 +462,9 @@ static struct i2c_bus_recovery_info uniphier_fi2c_bus_recovery_info = { .unprepare_recovery = uniphier_fi2c_unprepare_recovery, }; -static void uniphier_fi2c_hw_init(struct uniphier_fi2c_priv *priv, - u32 bus_speed, unsigned long clk_rate) +static void uniphier_fi2c_hw_init(struct uniphier_fi2c_priv *priv) { + unsigned int cyc = priv->clk_cycle; u32 tmp; tmp = readl(priv->membase + UNIPHIER_FI2C_CR); @@ -472,12 +473,10 @@ static void uniphier_fi2c_hw_init(struct uniphier_fi2c_priv *priv, uniphier_fi2c_reset(priv); - tmp = clk_rate / bus_speed; - - writel(tmp, priv->membase + UNIPHIER_FI2C_CYC); - writel(tmp / 2, priv->membase + UNIPHIER_FI2C_LCTL); - writel(tmp / 2, priv->membase + UNIPHIER_FI2C_SSUT); - writel(tmp / 16, priv->membase + UNIPHIER_FI2C_DSUT); + writel(cyc, priv->membase + UNIPHIER_FI2C_CYC); + writel(cyc / 2, priv->membase + UNIPHIER_FI2C_LCTL); + writel(cyc / 2, priv->membase + UNIPHIER_FI2C_SSUT); + writel(cyc / 16, priv->membase + UNIPHIER_FI2C_DSUT); uniphier_fi2c_prepare_operation(priv); } @@ -531,6 +530,7 @@ static int uniphier_fi2c_probe(struct platform_device *pdev) goto disable_clk; } + priv->clk_cycle = clk_rate / bus_speed; init_completion(&priv->comp); priv->adap.owner = THIS_MODULE; priv->adap.algo = &uniphier_fi2c_algo; @@ -541,7 +541,7 @@ static int uniphier_fi2c_probe(struct platform_device *pdev) i2c_set_adapdata(&priv->adap, priv); platform_set_drvdata(pdev, priv); - uniphier_fi2c_hw_init(priv, bus_speed, clk_rate); + uniphier_fi2c_hw_init(priv); ret = devm_request_irq(dev, irq, uniphier_fi2c_interrupt, 0, pdev->name, priv); @@ -568,6 +568,33 @@ static int uniphier_fi2c_remove(struct platform_device *pdev) return 0; } +static int __maybe_unused uniphier_fi2c_suspend(struct device *dev) +{ + struct uniphier_fi2c_priv *priv = dev_get_drvdata(dev); + + clk_disable_unprepare(priv->clk); + + return 0; +} + +static int __maybe_unused uniphier_fi2c_resume(struct device *dev) +{ + struct uniphier_fi2c_priv *priv = dev_get_drvdata(dev); + int ret; + + ret = clk_prepare_enable(priv->clk); + if (ret) + return ret; + + uniphier_fi2c_hw_init(priv); + + return 0; +} + +static const struct dev_pm_ops uniphier_fi2c_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(uniphier_fi2c_suspend, uniphier_fi2c_resume) +}; + static const struct of_device_id uniphier_fi2c_match[] = { { .compatible = "socionext,uniphier-fi2c" }, { /* sentinel */ } @@ -580,6 +607,7 @@ static struct platform_driver uniphier_fi2c_drv = { .driver = { .name = "uniphier-fi2c", .of_match_table = uniphier_fi2c_match, + .pm = &uniphier_fi2c_pm_ops, }, }; module_platform_driver(uniphier_fi2c_drv); -- 2.7.4