mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 10:49:33 +00:00
i2c: stm32f7: add PM_SLEEP suspend/resume support
Backup/restore I2C registers as part of the suspend/resume handlers. The device is marked as suspended to ensure that transfers are rejected during the suspended period. Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Alain Volmat <alain.volmat@st.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
parent
9253975bcb
commit
ea6dd25dee
1 changed files with 113 additions and 4 deletions
|
@ -168,6 +168,24 @@
|
|||
|
||||
#define STM32F7_AUTOSUSPEND_DELAY (HZ / 100)
|
||||
|
||||
/**
|
||||
* struct stm32f7_i2c_regs - i2c f7 registers backup
|
||||
* @cr1: Control register 1
|
||||
* @cr2: Control register 2
|
||||
* @oar1: Own address 1 register
|
||||
* @oar2: Own address 2 register
|
||||
* @pecr: PEC register
|
||||
* @tmgr: Timing register
|
||||
*/
|
||||
struct stm32f7_i2c_regs {
|
||||
u32 cr1;
|
||||
u32 cr2;
|
||||
u32 oar1;
|
||||
u32 oar2;
|
||||
u32 pecr;
|
||||
u32 tmgr;
|
||||
};
|
||||
|
||||
/**
|
||||
* struct stm32f7_i2c_spec - private i2c specification timing
|
||||
* @rate: I2C bus speed (Hz)
|
||||
|
@ -276,6 +294,7 @@ struct stm32f7_i2c_msg {
|
|||
* @timing: I2C computed timings
|
||||
* @slave: list of slave devices registered on the I2C bus
|
||||
* @slave_running: slave device currently used
|
||||
* @backup_regs: backup of i2c controller registers (for suspend/resume)
|
||||
* @slave_dir: transfer direction for the current slave device
|
||||
* @master_mode: boolean to know in which mode the I2C is running (master or
|
||||
* slave)
|
||||
|
@ -298,6 +317,7 @@ struct stm32f7_i2c_dev {
|
|||
struct stm32f7_i2c_timings timing;
|
||||
struct i2c_client *slave[STM32F7_I2C_MAX_SLAVE];
|
||||
struct i2c_client *slave_running;
|
||||
struct stm32f7_i2c_regs backup_regs;
|
||||
u32 slave_dir;
|
||||
bool master_mode;
|
||||
struct stm32_i2c_dma *dma;
|
||||
|
@ -2027,8 +2047,7 @@ static int stm32f7_i2c_remove(struct platform_device *pdev)
|
|||
return 0;
|
||||
}
|
||||
|
||||
#ifdef CONFIG_PM
|
||||
static int stm32f7_i2c_runtime_suspend(struct device *dev)
|
||||
static int __maybe_unused stm32f7_i2c_runtime_suspend(struct device *dev)
|
||||
{
|
||||
struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
|
||||
|
||||
|
@ -2038,7 +2057,7 @@ static int stm32f7_i2c_runtime_suspend(struct device *dev)
|
|||
return 0;
|
||||
}
|
||||
|
||||
static int stm32f7_i2c_runtime_resume(struct device *dev)
|
||||
static int __maybe_unused stm32f7_i2c_runtime_resume(struct device *dev)
|
||||
{
|
||||
struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
|
||||
int ret;
|
||||
|
@ -2053,11 +2072,101 @@ static int stm32f7_i2c_runtime_resume(struct device *dev)
|
|||
|
||||
return 0;
|
||||
}
|
||||
#endif
|
||||
|
||||
static int __maybe_unused
|
||||
stm32f7_i2c_regs_backup(struct stm32f7_i2c_dev *i2c_dev)
|
||||
{
|
||||
int ret;
|
||||
struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs;
|
||||
|
||||
ret = pm_runtime_get_sync(i2c_dev->dev);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
backup_regs->cr1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR1);
|
||||
backup_regs->cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2);
|
||||
backup_regs->oar1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR1);
|
||||
backup_regs->oar2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR2);
|
||||
backup_regs->pecr = readl_relaxed(i2c_dev->base + STM32F7_I2C_PECR);
|
||||
backup_regs->tmgr = readl_relaxed(i2c_dev->base + STM32F7_I2C_TIMINGR);
|
||||
|
||||
pm_runtime_put_sync(i2c_dev->dev);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int __maybe_unused
|
||||
stm32f7_i2c_regs_restore(struct stm32f7_i2c_dev *i2c_dev)
|
||||
{
|
||||
u32 cr1;
|
||||
int ret;
|
||||
struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs;
|
||||
|
||||
ret = pm_runtime_get_sync(i2c_dev->dev);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
cr1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR1);
|
||||
if (cr1 & STM32F7_I2C_CR1_PE)
|
||||
stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1,
|
||||
STM32F7_I2C_CR1_PE);
|
||||
|
||||
writel_relaxed(backup_regs->tmgr, i2c_dev->base + STM32F7_I2C_TIMINGR);
|
||||
writel_relaxed(backup_regs->cr1 & ~STM32F7_I2C_CR1_PE,
|
||||
i2c_dev->base + STM32F7_I2C_CR1);
|
||||
if (backup_regs->cr1 & STM32F7_I2C_CR1_PE)
|
||||
stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1,
|
||||
STM32F7_I2C_CR1_PE);
|
||||
writel_relaxed(backup_regs->cr2, i2c_dev->base + STM32F7_I2C_CR2);
|
||||
writel_relaxed(backup_regs->oar1, i2c_dev->base + STM32F7_I2C_OAR1);
|
||||
writel_relaxed(backup_regs->oar2, i2c_dev->base + STM32F7_I2C_OAR2);
|
||||
writel_relaxed(backup_regs->pecr, i2c_dev->base + STM32F7_I2C_PECR);
|
||||
|
||||
pm_runtime_put_sync(i2c_dev->dev);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int __maybe_unused stm32f7_i2c_suspend(struct device *dev)
|
||||
{
|
||||
struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
|
||||
int ret;
|
||||
|
||||
i2c_mark_adapter_suspended(&i2c_dev->adap);
|
||||
ret = stm32f7_i2c_regs_backup(i2c_dev);
|
||||
if (ret < 0) {
|
||||
i2c_mark_adapter_resumed(&i2c_dev->adap);
|
||||
return ret;
|
||||
}
|
||||
|
||||
pinctrl_pm_select_sleep_state(dev);
|
||||
pm_runtime_force_suspend(dev);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int __maybe_unused stm32f7_i2c_resume(struct device *dev)
|
||||
{
|
||||
struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);
|
||||
int ret;
|
||||
|
||||
ret = pm_runtime_force_resume(dev);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
pinctrl_pm_select_default_state(dev);
|
||||
|
||||
ret = stm32f7_i2c_regs_restore(i2c_dev);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
i2c_mark_adapter_resumed(&i2c_dev->adap);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct dev_pm_ops stm32f7_i2c_pm_ops = {
|
||||
SET_RUNTIME_PM_OPS(stm32f7_i2c_runtime_suspend,
|
||||
stm32f7_i2c_runtime_resume, NULL)
|
||||
SET_SYSTEM_SLEEP_PM_OPS(stm32f7_i2c_suspend, stm32f7_i2c_resume)
|
||||
};
|
||||
|
||||
static const struct of_device_id stm32f7_i2c_match[] = {
|
||||
|
|
Loading…
Reference in a new issue