diff options
| author | Masahiro Yamada <yamada.masahiro@socionext.com> | 2017-07-31 08:53:06 +0300 |
|---|---|---|
| committer | Wolfram Sang <wsa@the-dreams.de> | 2017-08-12 16:38:13 +0300 |
| commit | 9f9d6a40108e93b8d913e82cd43eb081885fd9ca (patch) | |
| tree | a96c76eebd6699e34a3ef737537586802b72bbfb | |
| parent | 8dc0f8c73c54c9d1a7fe8188ef3e70123a960eaf (diff) | |
| download | linux-9f9d6a40108e93b8d913e82cd43eb081885fd9ca.tar.xz | |
i2c: uniphier: 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 <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| -rw-r--r-- | drivers/i2c/busses/i2c-uniphier.c | 40 |
1 files changed, 35 insertions, 5 deletions
diff --git a/drivers/i2c/busses/i2c-uniphier.c b/drivers/i2c/busses/i2c-uniphier.c index 777c0fe93653..bb181b088291 100644 --- a/drivers/i2c/busses/i2c-uniphier.c +++ b/drivers/i2c/busses/i2c-uniphier.c @@ -53,6 +53,7 @@ struct uniphier_i2c_priv { void __iomem *membase; struct clk *clk; unsigned int busy_cnt; + unsigned int clk_cycle; }; static irqreturn_t uniphier_i2c_interrupt(int irq, void *dev_id) @@ -316,13 +317,13 @@ static struct i2c_bus_recovery_info uniphier_i2c_bus_recovery_info = { .unprepare_recovery = uniphier_i2c_unprepare_recovery, }; -static void uniphier_i2c_hw_init(struct uniphier_i2c_priv *priv, - u32 bus_speed, unsigned long clk_rate) +static void uniphier_i2c_hw_init(struct uniphier_i2c_priv *priv) { + unsigned int cyc = priv->clk_cycle; + uniphier_i2c_reset(priv, true); - writel((clk_rate / bus_speed / 2 << 16) | (clk_rate / bus_speed), - priv->membase + UNIPHIER_I2C_CLK); + writel((cyc / 2 << 16) | cyc, priv->membase + UNIPHIER_I2C_CLK); uniphier_i2c_reset(priv, false); } @@ -376,6 +377,7 @@ static int uniphier_i2c_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_i2c_algo; @@ -386,7 +388,7 @@ static int uniphier_i2c_probe(struct platform_device *pdev) i2c_set_adapdata(&priv->adap, priv); platform_set_drvdata(pdev, priv); - uniphier_i2c_hw_init(priv, bus_speed, clk_rate); + uniphier_i2c_hw_init(priv); ret = devm_request_irq(dev, irq, uniphier_i2c_interrupt, 0, pdev->name, priv); @@ -413,6 +415,33 @@ static int uniphier_i2c_remove(struct platform_device *pdev) return 0; } +static int __maybe_unused uniphier_i2c_suspend(struct device *dev) +{ + struct uniphier_i2c_priv *priv = dev_get_drvdata(dev); + + clk_disable_unprepare(priv->clk); + + return 0; +} + +static int __maybe_unused uniphier_i2c_resume(struct device *dev) +{ + struct uniphier_i2c_priv *priv = dev_get_drvdata(dev); + int ret; + + ret = clk_prepare_enable(priv->clk); + if (ret) + return ret; + + uniphier_i2c_hw_init(priv); + + return 0; +} + +static const struct dev_pm_ops uniphier_i2c_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(uniphier_i2c_suspend, uniphier_i2c_resume) +}; + static const struct of_device_id uniphier_i2c_match[] = { { .compatible = "socionext,uniphier-i2c" }, { /* sentinel */ } @@ -425,6 +454,7 @@ static struct platform_driver uniphier_i2c_drv = { .driver = { .name = "uniphier-i2c", .of_match_table = uniphier_i2c_match, + .pm = &uniphier_i2c_pm_ops, }, }; module_platform_driver(uniphier_i2c_drv); |