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[PATCH v3 10/12] spi: offload trigger: add ADI Util Sigma-Delta SPI driver

David Lechner posted 12 patches 3 months, 1 week ago
There is a newer version of this series
[PATCH v3 10/12] spi: offload trigger: add ADI Util Sigma-Delta SPI driver
Posted by David Lechner 3 months, 1 week ago 
Add a new driver for the ADI Util Sigma-Delta SPI FPGA IP core.

This is used to trigger a SPI offload based on a RDY signal from an ADC
while masking out other signals on the same line.

Signed-off-by: David Lechner <dlechner@baylibre.com>
---
 MAINTAINERS                                        |  2 +-
 drivers/spi/Kconfig                                |  5 ++
 drivers/spi/Makefile                               |  1 +
 .../spi/spi-offload-trigger-adi-util-sigma-delta.c | 62 ++++++++++++++++++++++
 4 files changed, 69 insertions(+), 1 deletion(-)

diff --git a/MAINTAINERS b/MAINTAINERS
index 60ba572be7f5b48c0ab1d0d9724e19e335e8761b..4ed4977deb6ddc545be39b5c1d5e9959e9fe64cf 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -23357,7 +23357,7 @@ F:	include/linux/mtd/spi-nor.h
 
 SPI OFFLOAD
 R:	David Lechner <dlechner@baylibre.com>
-F:	drivers/spi/spi-offload-trigger-pwm.c
+F:	drivers/spi/spi-offload-trigger-*.c
 F:	drivers/spi/spi-offload.c
 F:	include/linux/spi/offload/
 K:	spi_offload
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index c51da3fc3604977b05388687e5e64a58370186c4..e69f060d3875c168a2dc701a372e47b8ffd33268 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -1355,6 +1355,11 @@ if SPI_OFFLOAD
 
 comment "SPI Offload triggers"
 
+config SPI_OFFLOAD_TRIGGER_ADI_UTIL_SD
+	tristate "SPI offload trigger using ADI sigma-delta utility"
+	help
+	  SPI offload trigger from ADI sigma-delta utility FPGA IP block.
+
 config SPI_OFFLOAD_TRIGGER_PWM
 	tristate "SPI offload trigger using PWM"
 	depends on PWM
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 4ea89f6fc531625060255ecff237470927e1f041..51f9f16ed734424ff10672a04f2ec166dc637e0b 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -170,3 +170,4 @@ obj-$(CONFIG_SPI_SLAVE_SYSTEM_CONTROL)	+= spi-slave-system-control.o
 
 # SPI offload triggers
 obj-$(CONFIG_SPI_OFFLOAD_TRIGGER_PWM)	+= spi-offload-trigger-pwm.o
+obj-$(CONFIG_SPI_OFFLOAD_TRIGGER_ADI_UTIL_SD) += spi-offload-trigger-adi-util-sigma-delta.o
diff --git a/drivers/spi/spi-offload-trigger-adi-util-sigma-delta.c b/drivers/spi/spi-offload-trigger-adi-util-sigma-delta.c
new file mode 100644
index 0000000000000000000000000000000000000000..8468c773713a3d203b2e668f340ee3f477b8fb6c
--- /dev/null
+++ b/drivers/spi/spi-offload-trigger-adi-util-sigma-delta.c
@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2025 Analog Devices Inc.
+ * Copyright (C) 2025 BayLibre, SAS
+ */
+
+#include <linux/clk.h>
+#include <linux/dev_printk.h>
+#include <linux/err.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/spi/offload/provider.h>
+#include <linux/spi/offload/types.h>
+#include <linux/types.h>
+
+static bool adi_util_sigma_delta_match(struct spi_offload_trigger *trigger,
+				       enum spi_offload_trigger_type type,
+				       u64 *args, u32 nargs)
+{
+	return type == SPI_OFFLOAD_TRIGGER_DATA_READY && nargs == 0;
+}
+
+static const struct spi_offload_trigger_ops adi_util_sigma_delta_ops = {
+	.match = adi_util_sigma_delta_match,
+};
+
+static int adi_util_sigma_delta_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct spi_offload_trigger_info info = {
+		.fwnode = dev_fwnode(dev),
+		.ops = &adi_util_sigma_delta_ops,
+	};
+	struct clk *clk;
+
+	clk = devm_clk_get_enabled(dev, NULL);
+	if (IS_ERR(clk))
+		return dev_err_probe(dev, PTR_ERR(clk), "Failed to get clock\n");
+
+	return devm_spi_offload_trigger_register(dev, &info);
+}
+
+static const struct of_device_id adi_util_sigma_delta_of_match_table[] = {
+	{ .compatible = "adi,util-sigma-delta-spi", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, adi_util_sigma_delta_of_match_table);
+
+static struct platform_driver adi_util_sigma_delta_driver = {
+	.probe  = adi_util_sigma_delta_probe,
+	.driver = {
+		.name = "adi-util-sigma-delta-spi",
+		.of_match_table = adi_util_sigma_delta_of_match_table,
+	},
+};
+module_platform_driver(adi_util_sigma_delta_driver);
+
+MODULE_AUTHOR("David Lechner <dlechner@baylibre.com>");
+MODULE_DESCRIPTION("ADI Sigma-Delta SPI offload trigger utility driver");
+MODULE_LICENSE("GPL");

-- 
2.43.0
Re: [PATCH v3 10/12] spi: offload trigger: add ADI Util Sigma-Delta SPI driver
Posted by Nuno Sá 3 months, 1 week ago 
On Tue, 2025-07-01 at 16:37 -0500, David Lechner wrote:
> Add a new driver for the ADI Util Sigma-Delta SPI FPGA IP core.
> 
> This is used to trigger a SPI offload based on a RDY signal from an ADC
> while masking out other signals on the same line.
> 
> Signed-off-by: David Lechner <dlechner@baylibre.com>
> ---
>  MAINTAINERS                                        |  2 +-
>  drivers/spi/Kconfig                                |  5 ++
>  drivers/spi/Makefile                               |  1 +
>  .../spi/spi-offload-trigger-adi-util-sigma-delta.c | 62
> ++++++++++++++++++++++
>  4 files changed, 69 insertions(+), 1 deletion(-)
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index
> 60ba572be7f5b48c0ab1d0d9724e19e335e8761b..4ed4977deb6ddc545be39b5c1d5e9959e9fe
> 64cf 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -23357,7 +23357,7 @@ F:	include/linux/mtd/spi-nor.h
>  
>  SPI OFFLOAD
>  R:	David Lechner <dlechner@baylibre.com>
> -F:	drivers/spi/spi-offload-trigger-pwm.c
> +F:	drivers/spi/spi-offload-trigger-*.c
>  F:	drivers/spi/spi-offload.c
>  F:	include/linux/spi/offload/
>  K:	spi_offload
> diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
> index
> c51da3fc3604977b05388687e5e64a58370186c4..e69f060d3875c168a2dc701a372e47b8ffd3
> 3268 100644
> --- a/drivers/spi/Kconfig
> +++ b/drivers/spi/Kconfig
> @@ -1355,6 +1355,11 @@ if SPI_OFFLOAD
>  
>  comment "SPI Offload triggers"
>  
> +config SPI_OFFLOAD_TRIGGER_ADI_UTIL_SD
> +	tristate "SPI offload trigger using ADI sigma-delta utility"
> +	help
> +	  SPI offload trigger from ADI sigma-delta utility FPGA IP block.
> +
>  config SPI_OFFLOAD_TRIGGER_PWM
>  	tristate "SPI offload trigger using PWM"
>  	depends on PWM
> diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
> index
> 4ea89f6fc531625060255ecff237470927e1f041..51f9f16ed734424ff10672a04f2ec166dc63
> 7e0b 100644
> --- a/drivers/spi/Makefile
> +++ b/drivers/spi/Makefile
> @@ -170,3 +170,4 @@ obj-$(CONFIG_SPI_SLAVE_SYSTEM_CONTROL)	+= spi-slave-
> system-control.o
>  
>  # SPI offload triggers
>  obj-$(CONFIG_SPI_OFFLOAD_TRIGGER_PWM)	+= spi-offload-trigger-pwm.o
> +obj-$(CONFIG_SPI_OFFLOAD_TRIGGER_ADI_UTIL_SD) += spi-offload-trigger-adi-
> util-sigma-delta.o
> diff --git a/drivers/spi/spi-offload-trigger-adi-util-sigma-delta.c
> b/drivers/spi/spi-offload-trigger-adi-util-sigma-delta.c
> new file mode 100644
> index
> 0000000000000000000000000000000000000000..8468c773713a3d203b2e668f340ee3f477b8
> fb6c
> --- /dev/null
> +++ b/drivers/spi/spi-offload-trigger-adi-util-sigma-delta.c
> @@ -0,0 +1,62 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2025 Analog Devices Inc.
> + * Copyright (C) 2025 BayLibre, SAS
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/dev_printk.h>
> +#include <linux/err.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/property.h>
> +#include <linux/spi/offload/provider.h>
> +#include <linux/spi/offload/types.h>
> +#include <linux/types.h>
> +
> +static bool adi_util_sigma_delta_match(struct spi_offload_trigger *trigger,
> +				       enum spi_offload_trigger_type type,
> +				       u64 *args, u32 nargs)
> +{
> +	return type == SPI_OFFLOAD_TRIGGER_DATA_READY && nargs == 0;
> +}
> +
> +static const struct spi_offload_trigger_ops adi_util_sigma_delta_ops = {
> +	.match = adi_util_sigma_delta_match,
> +};
> +
> +static int adi_util_sigma_delta_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct spi_offload_trigger_info info = {
> +		.fwnode = dev_fwnode(dev),
> +		.ops = &adi_util_sigma_delta_ops,
> +	};
> +	struct clk *clk;
> +
> +	clk = devm_clk_get_enabled(dev, NULL);
> +	if (IS_ERR(clk))
> +		return dev_err_probe(dev, PTR_ERR(clk), "Failed to get
> clock\n");
> +

Small nit. Did you consider enabling/disabling the clock on the trigger
enable()/disable() callback? I guess the ref clk will be enabled anyways by
someone else but conceptually kind of makes sense to enable the resource only
when needed.

Not a big deal (at least to me).

- Nuno Sá

> +	return devm_spi_offload_trigger_register(dev, &info);
> +}
> +
> +static const struct of_device_id adi_util_sigma_delta_of_match_table[] = {
> +	{ .compatible = "adi,util-sigma-delta-spi", },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(of, adi_util_sigma_delta_of_match_table);
> +
> +static struct platform_driver adi_util_sigma_delta_driver = {
> +	.probe  = adi_util_sigma_delta_probe,
> +	.driver = {
> +		.name = "adi-util-sigma-delta-spi",
> +		.of_match_table = adi_util_sigma_delta_of_match_table,
> +	},
> +};
> +module_platform_driver(adi_util_sigma_delta_driver);
> +
> +MODULE_AUTHOR("David Lechner <dlechner@baylibre.com>");
> +MODULE_DESCRIPTION("ADI Sigma-Delta SPI offload trigger utility driver");
> +MODULE_LICENSE("GPL");
Re: [PATCH v3 10/12] spi: offload trigger: add ADI Util Sigma-Delta SPI driver
Posted by David Lechner 3 months, 1 week ago 
On 7/2/25 2:57 AM, Nuno Sá wrote:
> On Tue, 2025-07-01 at 16:37 -0500, David Lechner wrote:
>> Add a new driver for the ADI Util Sigma-Delta SPI FPGA IP core.
>>
>> This is used to trigger a SPI offload based on a RDY signal from an ADC
>> while masking out other signals on the same line.
>>
>> Signed-off-by: David Lechner <dlechner@baylibre.com>
>> ---

---

>> +static int adi_util_sigma_delta_probe(struct platform_device *pdev)
>> +{
>> +	struct device *dev = &pdev->dev;
>> +	struct spi_offload_trigger_info info = {
>> +		.fwnode = dev_fwnode(dev),
>> +		.ops = &adi_util_sigma_delta_ops,
>> +	};
>> +	struct clk *clk;
>> +
>> +	clk = devm_clk_get_enabled(dev, NULL);
>> +	if (IS_ERR(clk))
>> +		return dev_err_probe(dev, PTR_ERR(clk), "Failed to get
>> clock\n");
>> +
> 
> Small nit. Did you consider enabling/disabling the clock on the trigger
> enable()/disable() callback? I guess the ref clk will be enabled anyways by
> someone else but conceptually kind of makes sense to enable the resource only
> when needed.
> 
> Not a big deal (at least to me).
> 
> - Nuno Sá
> 

I thought about it, but we don't do that for any other FPGA IP cores
so I didn't do it here either.

Since they all use the same AXI clock anyway, disabling the clock
here probably doesn't have any effect in practice since there will
always be other users of the same clock keeping it enabled.

Patchew 2.1-devel-b67e4c2

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