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[PATCH v4 4/6] spi: spi-axi-spi-engine: Add support for MOSI idle configuration

Marcelo Schmitt posted 6 patches 1 year, 6 months ago
There is a newer version of this series
[PATCH v4 4/6] spi: spi-axi-spi-engine: Add support for MOSI idle configuration
Posted by Marcelo Schmitt 1 year, 6 months ago 
Implement MOSI idle low and MOSI idle high to better support peripherals
that request specific MOSI behavior.

Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
---
 drivers/spi/spi-axi-spi-engine.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/spi/spi-axi-spi-engine.c b/drivers/spi/spi-axi-spi-engine.c
index 0aa31d745734..787e22ae80c0 100644
--- a/drivers/spi/spi-axi-spi-engine.c
+++ b/drivers/spi/spi-axi-spi-engine.c
@@ -41,6 +41,7 @@
 #define SPI_ENGINE_CONFIG_CPHA			BIT(0)
 #define SPI_ENGINE_CONFIG_CPOL			BIT(1)
 #define SPI_ENGINE_CONFIG_3WIRE			BIT(2)
+#define SPI_ENGINE_CONFIG_SDO_IDLE		BIT(3)
 
 #define SPI_ENGINE_INST_TRANSFER		0x0
 #define SPI_ENGINE_INST_ASSERT			0x1
@@ -132,6 +133,10 @@ static unsigned int spi_engine_get_config(struct spi_device *spi)
 		config |= SPI_ENGINE_CONFIG_CPHA;
 	if (spi->mode & SPI_3WIRE)
 		config |= SPI_ENGINE_CONFIG_3WIRE;
+	if (spi->mode & SPI_MOSI_IDLE_HIGH)
+		config |= SPI_ENGINE_CONFIG_SDO_IDLE;
+	if (spi->mode & SPI_MOSI_IDLE_LOW)
+		config &= ~SPI_ENGINE_CONFIG_SDO_IDLE;
 
 	return config;
 }
@@ -646,6 +651,9 @@ static int spi_engine_probe(struct platform_device *pdev)
 
 	host->dev.of_node = pdev->dev.of_node;
 	host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_3WIRE;
+	if (ADI_AXI_PCORE_VER_MAJOR(version) >= 1 &&
+	    ADI_AXI_PCORE_VER_MINOR(version) >= 3)
+		host->mode_bits |=  SPI_MOSI_IDLE_LOW | SPI_MOSI_IDLE_HIGH;
 	host->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
 	host->max_speed_hz = clk_get_rate(spi_engine->ref_clk) / 2;
 	host->transfer_one_message = spi_engine_transfer_one_message;
-- 
2.43.0
Re: [PATCH v4 4/6] spi: spi-axi-spi-engine: Add support for MOSI idle configuration
Posted by David Lechner 1 year, 6 months ago 
On 6/18/24 6:11 PM, Marcelo Schmitt wrote:
> Implement MOSI idle low and MOSI idle high to better support peripherals
> that request specific MOSI behavior.
> 
> Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
> ---
>  drivers/spi/spi-axi-spi-engine.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/spi/spi-axi-spi-engine.c b/drivers/spi/spi-axi-spi-engine.c
> index 0aa31d745734..787e22ae80c0 100644
> --- a/drivers/spi/spi-axi-spi-engine.c
> +++ b/drivers/spi/spi-axi-spi-engine.c
> @@ -41,6 +41,7 @@
>  #define SPI_ENGINE_CONFIG_CPHA			BIT(0)
>  #define SPI_ENGINE_CONFIG_CPOL			BIT(1)
>  #define SPI_ENGINE_CONFIG_3WIRE			BIT(2)
> +#define SPI_ENGINE_CONFIG_SDO_IDLE		BIT(3)

Calling this SPI_ENGINE_CONFIG_SDO_IDLE_HIGH would make it more
clear what happens when the bit is enabled.

>  
>  #define SPI_ENGINE_INST_TRANSFER		0x0
>  #define SPI_ENGINE_INST_ASSERT			0x1
> @@ -132,6 +133,10 @@ static unsigned int spi_engine_get_config(struct spi_device *spi)
>  		config |= SPI_ENGINE_CONFIG_CPHA;
>  	if (spi->mode & SPI_3WIRE)
>  		config |= SPI_ENGINE_CONFIG_3WIRE;
> +	if (spi->mode & SPI_MOSI_IDLE_HIGH)
> +		config |= SPI_ENGINE_CONFIG_SDO_IDLE;
> +	if (spi->mode & SPI_MOSI_IDLE_LOW)
> +		config &= ~SPI_ENGINE_CONFIG_SDO_IDLE;
>  
>  	return config;
>  }
> @@ -646,6 +651,9 @@ static int spi_engine_probe(struct platform_device *pdev)
>  
>  	host->dev.of_node = pdev->dev.of_node;
>  	host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_3WIRE;
> +	if (ADI_AXI_PCORE_VER_MAJOR(version) >= 1 &&

Currently, the major version is required to be 1, so this check is not
strictly needed.

> +	    ADI_AXI_PCORE_VER_MINOR(version) >= 3)
> +		host->mode_bits |=  SPI_MOSI_IDLE_LOW | SPI_MOSI_IDLE_HIGH;



>  	host->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
>  	host->max_speed_hz = clk_get_rate(spi_engine->ref_clk) / 2;
>  	host->transfer_one_message = spi_engine_transfer_one_message;
Re: [PATCH v4 4/6] spi: spi-axi-spi-engine: Add support for MOSI idle configuration
Posted by Marcelo Schmitt 1 year, 6 months ago 
On 06/19, David Lechner wrote:
> On 6/18/24 6:11 PM, Marcelo Schmitt wrote:
> > Implement MOSI idle low and MOSI idle high to better support peripherals
> > that request specific MOSI behavior.
> > 
> > Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
> > ---
> >  drivers/spi/spi-axi-spi-engine.c | 8 ++++++++
> >  1 file changed, 8 insertions(+)
> > 
> > diff --git a/drivers/spi/spi-axi-spi-engine.c b/drivers/spi/spi-axi-spi-engine.c
> > index 0aa31d745734..787e22ae80c0 100644
> > --- a/drivers/spi/spi-axi-spi-engine.c
> > +++ b/drivers/spi/spi-axi-spi-engine.c
> > @@ -41,6 +41,7 @@
> >  #define SPI_ENGINE_CONFIG_CPHA			BIT(0)
> >  #define SPI_ENGINE_CONFIG_CPOL			BIT(1)
> >  #define SPI_ENGINE_CONFIG_3WIRE			BIT(2)
> > +#define SPI_ENGINE_CONFIG_SDO_IDLE		BIT(3)
> 
> Calling this SPI_ENGINE_CONFIG_SDO_IDLE_HIGH would make it more
> clear what happens when the bit is enabled.

Yeah, agreed. Changing to SPI_ENGINE_CONFIG_SDO_IDLE_HIGH.

> 
> >  
> >  #define SPI_ENGINE_INST_TRANSFER		0x0
> >  #define SPI_ENGINE_INST_ASSERT			0x1
> > @@ -132,6 +133,10 @@ static unsigned int spi_engine_get_config(struct spi_device *spi)
> >  		config |= SPI_ENGINE_CONFIG_CPHA;
> >  	if (spi->mode & SPI_3WIRE)
> >  		config |= SPI_ENGINE_CONFIG_3WIRE;
> > +	if (spi->mode & SPI_MOSI_IDLE_HIGH)
> > +		config |= SPI_ENGINE_CONFIG_SDO_IDLE;
> > +	if (spi->mode & SPI_MOSI_IDLE_LOW)
> > +		config &= ~SPI_ENGINE_CONFIG_SDO_IDLE;
> >  
> >  	return config;
> >  }
> > @@ -646,6 +651,9 @@ static int spi_engine_probe(struct platform_device *pdev)
> >  
> >  	host->dev.of_node = pdev->dev.of_node;
> >  	host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_3WIRE;
> > +	if (ADI_AXI_PCORE_VER_MAJOR(version) >= 1 &&
> 
> Currently, the major version is required to be 1, so this check is not
> strictly needed.
> 
This is expecting the MOSI idle feature to be available on all versions from 1.3 on.
Will SPI-Engine always be major version 1?

> > +	    ADI_AXI_PCORE_VER_MINOR(version) >= 3)
> > +		host->mode_bits |=  SPI_MOSI_IDLE_LOW | SPI_MOSI_IDLE_HIGH;
> 
> 
> 
> >  	host->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
> >  	host->max_speed_hz = clk_get_rate(spi_engine->ref_clk) / 2;
> >  	host->transfer_one_message = spi_engine_transfer_one_message;
>
Re: [PATCH v4 4/6] spi: spi-axi-spi-engine: Add support for MOSI idle configuration
Posted by David Lechner 1 year, 6 months ago 
On 6/19/24 12:27 PM, Marcelo Schmitt wrote:
> On 06/19, David Lechner wrote:
>> On 6/18/24 6:11 PM, Marcelo Schmitt wrote:



>>> @@ -646,6 +651,9 @@ static int spi_engine_probe(struct platform_device *pdev)
>>>  
>>>  	host->dev.of_node = pdev->dev.of_node;
>>>  	host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_3WIRE;
>>> +	if (ADI_AXI_PCORE_VER_MAJOR(version) >= 1 &&
>>
>> Currently, the major version is required to be 1, so this check is not
>> strictly needed.
>>
> This is expecting the MOSI idle feature to be available on all versions from 1.3 on.
> Will SPI-Engine always be major version 1?

<yoda voice>Difficult to see, the future is.</yoda voice>

It's fine if you want to leave it the way it is.

> 
>>> +	    ADI_AXI_PCORE_VER_MINOR(version) >= 3)
>>> +		host->mode_bits |=  SPI_MOSI_IDLE_LOW | SPI_MOSI_IDLE_HIGH;
>>

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