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i2c: imx-lpi2c: add runtime pm support

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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>
This commit is contained in:
Fugang Duan 2018-01-02 17:11:52 +08:00 committed by Wolfram Sang
parent fe34fbf93f
commit 13d6eb20fc
1 changed files with 51 additions and 17 deletions
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68
drivers/i2c/busses/i2c-imx-lpi2c.c
View file

@ -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,
},
};