Commit bf22461e authored by Alain Volmat's avatar Alain Volmat Committed by Wolfram Sang
Browse files

i2c: stm32f7: do not backup read-only PECR register 



The PECR register provides received packet computed PEC value. 
It makes no sense restoring its value after a reset, and anyway,
as read-only register it cannot be restored.

Fixes: ea6dd25d ("i2c: stm32f7: add PM_SLEEP suspend/resume support")
Signed-off-by: default avatarAlain Volmat <alain.volmat@st.com>
Reviewed-by: default avatarPierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
parent a47070aa

drivers/i2c/busses/i2c-stm32f7.c

+0 −4
Original line number Diff line number Diff line
@@ -176,7 +176,6 @@ 
 * @cr2: Control register 2

 * @oar1: Own address 1 register

 * @oar2: Own address 2 register

 * @pecr: PEC register

 * @tmgr: Timing register

 */

struct stm32f7_i2c_regs {
@@ -184,7 +183,6 @@ struct stm32f7_i2c_regs { 
	u32 cr2;

	u32 oar1;

	u32 oar2;

	u32 pecr;

	u32 tmgr;

};
@@ -2196,7 +2194,6 @@ static int stm32f7_i2c_regs_backup(struct stm32f7_i2c_dev *i2c_dev) 
	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);

	stm32f7_i2c_write_fm_plus_bits(i2c_dev, false);
@@ -2229,7 +2226,6 @@ static int stm32f7_i2c_regs_restore(struct stm32f7_i2c_dev *i2c_dev) 
	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);

	stm32f7_i2c_write_fm_plus_bits(i2c_dev, true);



	pm_runtime_put_sync(i2c_dev->dev);

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