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authorFugang Duan <fugang.duan@nxp.com>2018-01-02 17:11:52 +0800
committerWolfram Sang <wsa@the-dreams.de>2018-01-24 07:20:30 +0100
commit13d6eb20fc79a1e606307256dad4098375539a09 (patch)
treebaa432a295e9a72e589696a6b250c72e1bcba369 /drivers/i2c
parentfe34fbf93f87e9e0f78eeeb6f21b2fc310cb6080 (diff)
i2c: imx-lpi2c: add runtime pm support
Add runtime pm support to dynamically manage the clock to avoid enable/disable clock in frequently that can improve the i2c bus transfer performance. And use pm_runtime_force_suspend/resume() instead of lpi2c_imx_suspend/resume(). Signed-off-by: Fugang Duan <fugang.duan@nxp.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-imx-lpi2c.c68
1 files changed, 51 insertions, 17 deletions
diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c b/drivers/i2c/busses/i2c-imx-lpi2c.c
index e86801a63120..e6da2c7a9a3e 100644
--- a/drivers/i2c/busses/i2c-imx-lpi2c.c
+++ b/drivers/i2c/busses/i2c-imx-lpi2c.c
@@ -30,6 +30,7 @@
#include <linux/of_device.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include <linux/sched.h>
#include <linux/slab.h>
@@ -90,6 +91,8 @@
#define FAST_PLUS_MAX_BITRATE 3400000
#define HIGHSPEED_MAX_BITRATE 5000000
+#define I2C_PM_TIMEOUT 10 /* ms */
+
enum lpi2c_imx_mode {
STANDARD, /* 100+Kbps */
FAST, /* 400+Kbps */
@@ -274,8 +277,8 @@ static int lpi2c_imx_master_enable(struct lpi2c_imx_struct *lpi2c_imx)
unsigned int temp;
int ret;
- ret = clk_enable(lpi2c_imx->clk);
- if (ret)
+ ret = pm_runtime_get_sync(lpi2c_imx->adapter.dev.parent);
+ if (ret < 0)
return ret;
temp = MCR_RST;
@@ -284,7 +287,7 @@ static int lpi2c_imx_master_enable(struct lpi2c_imx_struct *lpi2c_imx)
ret = lpi2c_imx_config(lpi2c_imx);
if (ret)
- goto clk_disable;
+ goto rpm_put;
temp = readl(lpi2c_imx->base + LPI2C_MCR);
temp |= MCR_MEN;
@@ -292,8 +295,9 @@ static int lpi2c_imx_master_enable(struct lpi2c_imx_struct *lpi2c_imx)
return 0;
-clk_disable:
- clk_disable(lpi2c_imx->clk);
+rpm_put:
+ pm_runtime_mark_last_busy(lpi2c_imx->adapter.dev.parent);
+ pm_runtime_put_autosuspend(lpi2c_imx->adapter.dev.parent);
return ret;
}
@@ -306,7 +310,8 @@ static int lpi2c_imx_master_disable(struct lpi2c_imx_struct *lpi2c_imx)
temp &= ~MCR_MEN;
writel(temp, lpi2c_imx->base + LPI2C_MCR);
- clk_disable(lpi2c_imx->clk);
+ pm_runtime_mark_last_busy(lpi2c_imx->adapter.dev.parent);
+ pm_runtime_put_autosuspend(lpi2c_imx->adapter.dev.parent);
return 0;
}
@@ -606,22 +611,31 @@ static int lpi2c_imx_probe(struct platform_device *pdev)
return ret;
}
+ pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT);
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_get_noresume(&pdev->dev);
+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+
temp = readl(lpi2c_imx->base + LPI2C_PARAM);
lpi2c_imx->txfifosize = 1 << (temp & 0x0f);
lpi2c_imx->rxfifosize = 1 << ((temp >> 8) & 0x0f);
- clk_disable(lpi2c_imx->clk);
-
ret = i2c_add_adapter(&lpi2c_imx->adapter);
if (ret)
- goto clk_unprepare;
+ goto rpm_disable;
+
+ pm_runtime_mark_last_busy(&pdev->dev);
+ pm_runtime_put_autosuspend(&pdev->dev);
dev_info(&lpi2c_imx->adapter.dev, "LPI2C adapter registered\n");
return 0;
-clk_unprepare:
- clk_unprepare(lpi2c_imx->clk);
+rpm_disable:
+ pm_runtime_put(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_dont_use_autosuspend(&pdev->dev);
return ret;
}
@@ -632,28 +646,48 @@ static int lpi2c_imx_remove(struct platform_device *pdev)
i2c_del_adapter(&lpi2c_imx->adapter);
- clk_unprepare(lpi2c_imx->clk);
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_dont_use_autosuspend(&pdev->dev);
return 0;
}
#ifdef CONFIG_PM_SLEEP
-static int lpi2c_imx_suspend(struct device *dev)
+static int lpi2c_runtime_suspend(struct device *dev)
{
+ struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(lpi2c_imx->clk);
pinctrl_pm_select_sleep_state(dev);
return 0;
}
-static int lpi2c_imx_resume(struct device *dev)
+static int lpi2c_runtime_resume(struct device *dev)
{
+ struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev);
+ int ret;
+
pinctrl_pm_select_default_state(dev);
+ ret = clk_prepare_enable(lpi2c_imx->clk);
+ if (ret) {
+ dev_err(dev, "failed to enable I2C clock, ret=%d\n", ret);
+ return ret;
+ }
return 0;
}
-#endif
-static SIMPLE_DEV_PM_OPS(imx_lpi2c_pm, lpi2c_imx_suspend, lpi2c_imx_resume);
+static const struct dev_pm_ops lpi2c_pm_ops = {
+ SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ SET_RUNTIME_PM_OPS(lpi2c_runtime_suspend,
+ lpi2c_runtime_resume, NULL)
+};
+#define IMX_LPI2C_PM (&lpi2c_pm_ops)
+#else
+#define IMX_LPI2C_PM NULL
+#endif
static struct platform_driver lpi2c_imx_driver = {
.probe = lpi2c_imx_probe,
@@ -661,7 +695,7 @@ static struct platform_driver lpi2c_imx_driver = {
.driver = {
.name = DRIVER_NAME,
.of_match_table = lpi2c_imx_of_match,
- .pm = &imx_lpi2c_pm,
+ .pm = IMX_LPI2C_PM,
},
};

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