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i2c: Blackfin I2C Driver: Functional power management support

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PM_SUSPEND_MEM: Blackfin does not maintain register state through
Hibernate. Save and restore peripheral base initialization during
PM transitions.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
This commit is contained in:
Michael Hennerich 2008-07-27 14:41:54 +08:00 committed by Ben Dooks
parent 31321b76e1
commit 958585f58f
1 changed files with 24 additions and 11 deletions
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35
drivers/i2c/busses/i2c-bfin-twi.c
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@ -49,6 +49,8 @@ struct bfin_twi_iface {
struct i2c_msg *pmsg;
int msg_num;
int cur_msg;
u16 saved_clkdiv;
u16 saved_control;
void __iomem *regs_base;
};
@ -565,32 +567,43 @@ static u32 bfin_twi_functionality(struct i2c_adapter *adap)
I2C_FUNC_I2C;
}
static struct i2c_algorithm bfin_twi_algorithm = {
.master_xfer = bfin_twi_master_xfer,
.smbus_xfer = bfin_twi_smbus_xfer,
.functionality = bfin_twi_functionality,
};
static int i2c_bfin_twi_suspend(struct platform_device *dev, pm_message_t state)
static int i2c_bfin_twi_suspend(struct platform_device *pdev, pm_message_t state)
{
struct bfin_twi_iface *iface = platform_get_drvdata(dev);
struct bfin_twi_iface *iface = platform_get_drvdata(pdev);
iface->saved_clkdiv = read_CLKDIV(iface);
iface->saved_control = read_CONTROL(iface);
free_irq(iface->irq, iface);
/* Disable TWI */
write_CONTROL(iface, read_CONTROL(iface) & ~TWI_ENA);
SSYNC();
write_CONTROL(iface, iface->saved_control & ~TWI_ENA);
return 0;
}
static int i2c_bfin_twi_resume(struct platform_device *dev)
static int i2c_bfin_twi_resume(struct platform_device *pdev)
{
struct bfin_twi_iface *iface = platform_get_drvdata(dev);
struct bfin_twi_iface *iface = platform_get_drvdata(pdev);
/* Enable TWI */
write_CONTROL(iface, read_CONTROL(iface) | TWI_ENA);
SSYNC();
int rc = request_irq(iface->irq, bfin_twi_interrupt_entry,
IRQF_DISABLED, pdev->name, iface);
if (rc) {
dev_err(&pdev->dev, "Can't get IRQ %d !\n", iface->irq);
return -ENODEV;
}
/* Resume TWI interface clock as specified */
write_CLKDIV(iface, iface->saved_clkdiv);
/* Resume TWI */
write_CONTROL(iface, iface->saved_control);
return 0;
}