Commit 18dbdda8 authored by Dirk Brandewie's avatar Dirk Brandewie Committed by Ben Dooks

i2c-designware: Add runtime power management support

Add runtime power management to the PCI driver.
Signed-off-by: default avatarDirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: default avatarBen Dooks <ben-linux@fluff.org>
parent fe20ff5c
......@@ -31,6 +31,7 @@
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/pm_runtime.h>
#include <linux/delay.h>
#include "i2c-designware-core.h"
......@@ -501,6 +502,7 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
dev_dbg(dev->dev, "%s: msgs: %d\n", __func__, num);
mutex_lock(&dev->lock);
pm_runtime_get_sync(dev->dev);
INIT_COMPLETION(dev->cmd_complete);
dev->msgs = msgs;
......@@ -550,6 +552,7 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
ret = -EIO;
done:
pm_runtime_put(dev->dev);
mutex_unlock(&dev->lock);
return ret;
......@@ -671,10 +674,13 @@ void i2c_dw_enable(struct dw_i2c_dev *dev)
dw_writel(dev, 1, DW_IC_ENABLE);
}
void i2c_dw_disable(struct dw_i2c_dev *dev)
u32 i2c_dw_is_enabled(struct dw_i2c_dev *dev)
{
int ret;
return dw_readl(dev, DW_IC_ENABLE);
}
void i2c_dw_disable(struct dw_i2c_dev *dev)
{
/* Disable controller */
dw_writel(dev, 0, DW_IC_ENABLE);
......
......@@ -98,6 +98,7 @@ extern int i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
extern u32 i2c_dw_func(struct i2c_adapter *adap);
extern irqreturn_t i2c_dw_isr(int this_irq, void *dev_id);
extern void i2c_dw_enable(struct dw_i2c_dev *dev);
extern u32 i2c_dw_is_enabled(struct dw_i2c_dev *dev);
extern void i2c_dw_disable(struct dw_i2c_dev *dev);
extern void i2c_dw_clear_int(struct dw_i2c_dev *dev);
extern void i2c_dw_disable_int(struct dw_i2c_dev *dev);
......
......@@ -38,6 +38,7 @@
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/pm_runtime.h>
#include "i2c-designware-core.h"
#define DRIVER_NAME "i2c-designware-pci"
......@@ -137,6 +138,82 @@ static struct i2c_algorithm i2c_dw_algo = {
.functionality = i2c_dw_func,
};
static int i2c_dw_pci_suspend(struct pci_dev *pdev, pm_message_t mesg)
{
struct dw_i2c_dev *i2c = pci_get_drvdata(pdev);
int err;
i2c_dw_disable(i2c);
err = pci_save_state(pdev);
if (err) {
dev_err(&pdev->dev, "pci_save_state failed\n");
return err;
}
err = pci_set_power_state(pdev, PCI_D3hot);
if (err) {
dev_err(&pdev->dev, "pci_set_power_state failed\n");
return err;
}
return 0;
}
static int i2c_dw_pci_runtime_suspend(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
dev_dbg(dev, "PCI suspend called\n");
return i2c_dw_pci_suspend(pdev, PMSG_SUSPEND);
}
static int i2c_dw_pci_resume(struct pci_dev *pdev)
{
struct dw_i2c_dev *i2c = pci_get_drvdata(pdev);
int err;
u32 enabled;
enabled = i2c_dw_is_enabled(i2c);
if (enabled)
return 0;
err = pci_set_power_state(pdev, PCI_D0);
if (err) {
dev_err(&pdev->dev, "pci_set_power_state() failed\n");
return err;
}
pci_restore_state(pdev);
i2c_dw_init(i2c);
i2c_dw_enable(i2c);
return 0;
}
static int i2c_dw_pci_runtime_resume(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
dev_dbg(dev, "runtime_resume called\n");
return i2c_dw_pci_resume(pdev);
}
static int i2c_dw_pci_runtime_idle(struct device *dev)
{
int err = pm_schedule_suspend(dev, 500);
dev_dbg(dev, "runtime_idle called\n");
if (err != 0)
return 0;
return -EBUSY;
}
static const struct dev_pm_ops i2c_dw_pm_ops = {
.runtime_suspend = i2c_dw_pci_runtime_suspend,
.runtime_resume = i2c_dw_pci_runtime_resume,
.runtime_idle = i2c_dw_pci_runtime_idle,
};
static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
{
return dev->controller->clk_khz;
......@@ -245,6 +322,9 @@ const struct pci_device_id *id)
goto err_free_irq;
}
pm_runtime_put_noidle(&pdev->dev);
pm_runtime_allow(&pdev->dev);
return 0;
err_free_irq:
......@@ -264,6 +344,10 @@ static void __devexit i2c_dw_pci_remove(struct pci_dev *pdev)
{
struct dw_i2c_dev *dev = pci_get_drvdata(pdev);
i2c_dw_disable(dev);
pm_runtime_forbid(&pdev->dev);
pm_runtime_get_noresume(&pdev->dev);
pci_set_drvdata(pdev, NULL);
i2c_del_adapter(&dev->adapter);
put_device(&pdev->dev);
......@@ -297,6 +381,11 @@ static struct pci_driver dw_i2c_driver = {
.id_table = i2_designware_pci_ids,
.probe = i2c_dw_pci_probe,
.remove = __devexit_p(i2c_dw_pci_remove),
.resume = i2c_dw_pci_resume,
.suspend = i2c_dw_pci_suspend,
.driver = {
.pm = &i2c_dw_pm_ops,
},
};
static int __init dw_i2c_init_driver(void)
......
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