Re: [PATCH 3/5] i2c: i2c-stm32f7: add a new st,stm32mp15-i2c compatible

[Pierre Yves MORDRET]

Hi

Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@xxxxxx>

Thanks

On 1/23/20 5:12 PM, Alain Volmat wrote:
> Add a new stm32mp15 specific compatible to handle FastMode+
> registers handling which is different on the stm32mp15 compared
> to the stm32f7 or stm32h7.
> Indeed, on the stm32mp15, the FastMode+ set and clear registers
> are separated while on the other platforms (F7 or H7) the control
> is done in a unique register.
> 
> Signed-off-by: Alain Volmat <alain.volmat@xxxxxx>
> ---
>  drivers/i2c/busses/i2c-stm32f7.c | 41 +++++++++++++++++++++++++++++++++-------
>  1 file changed, 34 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c
> index 1a3b3fa582ff..6bee9eca789f 100644
> --- a/drivers/i2c/busses/i2c-stm32f7.c
> +++ b/drivers/i2c/busses/i2c-stm32f7.c
> @@ -223,6 +223,7 @@ struct stm32f7_i2c_spec {
>   * @fall_time: Fall time (ns)
>   * @dnf: Digital filter coefficient (0-16)
>   * @analog_filter: Analog filter delay (On/Off)
> + * @fmp_clr_offset: Fast Mode Plus clear register offset from set register
>   */
>  struct stm32f7_i2c_setup {
>  	enum stm32_i2c_speed speed;
> @@ -232,6 +233,7 @@ struct stm32f7_i2c_setup {
>  	u32 fall_time;
>  	u8 dnf;
>  	bool analog_filter;
> +	u32 fmp_clr_offset;
>  };
>  
>  /**
> @@ -303,8 +305,9 @@ struct stm32f7_i2c_msg {
>   * @dma: dma data
>   * @use_dma: boolean to know if dma is used in the current transfer
>   * @regmap: holds SYSCFG phandle for Fast Mode Plus bits
> - * @regmap_reg: register address for setting Fast Mode Plus bits
> - * @regmap_mask: mask for Fast Mode Plus bits in set register
> + * @regmap_sreg: register address for setting Fast Mode Plus bits
> + * @regmap_creg: register address for clearing Fast Mode Plus bits
> + * @regmap_mask: mask for Fast Mode Plus bits
>   * @wakeup_src: boolean to know if the device is a wakeup source
>   */
>  struct stm32f7_i2c_dev {
> @@ -328,7 +331,8 @@ struct stm32f7_i2c_dev {
>  	struct stm32_i2c_dma *dma;
>  	bool use_dma;
>  	struct regmap *regmap;
> -	u32 regmap_reg;
> +	u32 regmap_sreg;
> +	u32 regmap_creg;
>  	u32 regmap_mask;
>  	bool wakeup_src;
>  };
> @@ -386,6 +390,14 @@ static const struct stm32f7_i2c_setup stm32f7_setup = {
>  	.analog_filter = STM32F7_I2C_ANALOG_FILTER_ENABLE,
>  };
>  
> +static const struct stm32f7_i2c_setup stm32mp15_setup = {
> +	.rise_time = STM32F7_I2C_RISE_TIME_DEFAULT,
> +	.fall_time = STM32F7_I2C_FALL_TIME_DEFAULT,
> +	.dnf = STM32F7_I2C_DNF_DEFAULT,
> +	.analog_filter = STM32F7_I2C_ANALOG_FILTER_ENABLE,
> +	.fmp_clr_offset = 0x40,
> +};
> +
>  static inline void stm32f7_i2c_set_bits(void __iomem *reg, u32 mask)
>  {
>  	writel_relaxed(readl_relaxed(reg) | mask, reg);
> @@ -1822,15 +1834,26 @@ static int stm32f7_i2c_unreg_slave(struct i2c_client *slave)
>  static int stm32f7_i2c_write_fm_plus_bits(struct stm32f7_i2c_dev *i2c_dev,
>  					  bool enable)
>  {
> +	int ret;
> +
>  	if (i2c_dev->speed != STM32_I2C_SPEED_FAST_PLUS ||
>  	    IS_ERR_OR_NULL(i2c_dev->regmap)) {
>  		/* Optional */
>  		return 0;
>  	}
>  
> -	return regmap_update_bits(i2c_dev->regmap, i2c_dev->regmap_reg,
> -				  i2c_dev->regmap_mask,
> -				  enable ? i2c_dev->regmap_mask : 0);
> +	if (i2c_dev->regmap_sreg == i2c_dev->regmap_creg)
> +		ret = regmap_update_bits(i2c_dev->regmap,
> +					 i2c_dev->regmap_sreg,
> +					 i2c_dev->regmap_mask,
> +					 enable ? i2c_dev->regmap_mask : 0);
> +	else
> +		ret = regmap_write(i2c_dev->regmap,
> +				   enable ? i2c_dev->regmap_sreg :
> +					    i2c_dev->regmap_creg,
> +				   i2c_dev->regmap_mask);
> +
> +	return ret;
>  }
>  
>  static int stm32f7_i2c_setup_fm_plus_bits(struct platform_device *pdev,
> @@ -1846,10 +1869,13 @@ static int stm32f7_i2c_setup_fm_plus_bits(struct platform_device *pdev,
>  	}
>  
>  	ret = of_property_read_u32_index(np, "st,syscfg-fmp", 1,
> -					 &i2c_dev->regmap_reg);
> +					 &i2c_dev->regmap_sreg);
>  	if (ret)
>  		return ret;
>  
> +	i2c_dev->regmap_creg = i2c_dev->regmap_sreg +
> +			       i2c_dev->setup.fmp_clr_offset;
> +
>  	ret = of_property_read_u32_index(np, "st,syscfg-fmp", 2,
>  					 &i2c_dev->regmap_mask);
>  	if (ret)
> @@ -2271,6 +2297,7 @@ static const struct dev_pm_ops stm32f7_i2c_pm_ops = {
>  
>  static const struct of_device_id stm32f7_i2c_match[] = {
>  	{ .compatible = "st,stm32f7-i2c", .data = &stm32f7_setup},
> +	{ .compatible = "st,stm32mp15-i2c", .data = &stm32mp15_setup},
>  	{},
>  };
>  MODULE_DEVICE_TABLE(of, stm32f7_i2c_match);
>