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authorMasahiro Yamada <yamada.masahiro@socionext.com>2017-07-31 14:53:07 +0900
committerWolfram Sang <wsa@the-dreams.de>2017-08-12 15:38:23 +0200
commit822c8d45a170312e368271c3c8f43d49cac863a2 (patch)
treec8a5e04f393f302a0364e909bbcb9b69421a991b /drivers/i2c
parent9f9d6a40108e93b8d913e82cd43eb081885fd9ca (diff)
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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 <yamada.masahiro@socionext.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-uniphier-f.c46
1 files changed, 37 insertions, 9 deletions
diff --git a/drivers/i2c/busses/i2c-uniphier-f.c b/drivers/i2c/busses/i2c-uniphier-f.c
index beee31892295..9918bdd81619 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);