[PATCH v4 00/11] iio: add support for the ad3552r AXI DAC IP

[PATCH v4 00/11] iio: add support for the ad3552r AXI DAC IP

[Angelo Dureghello]

Purpose is to add ad3552r AXI DAC (fpga-based) support.

The "ad3552r" AXI IP, a variant of the generic "DAC" AXI IP,
has been created to reach the maximum speed (33MUPS) supported
from the ad3552r. To obtain the maximum transfer rate, a custom
IP core module has been implemented with a QSPI interface with 
DDR (Double Data Rate) mode.

The design is actually using the DAC backend since the register
map is the same of the generic DAC IP, except for some customized
bitfields. For this reason, a new "compatible" has been added
in adi-axi-dac.c.

Also, backend has been extended with all the needed functions
for this use case, keeping the names gneric.

The following patch is actually applying to linux-iio/testing.

---
Changes in v2:
- use unsigned int on bus_reg_read/write
- add a compatible in axi-dac backend for the ad3552r DAC IP
- minor code alignment fixes
- fix a return value not checked
- change devicetree structure setting ad3552r-axi as a backend
  subnode
- add synchronous_mode_available in the ABI doc

Changes in v3:
- changing AXI backend approach using a dac ip compatible
- fdt bindings updates accordingly
- fdt, ad3552r device must be a subnode of the backend
- allow probe of child devices
- passing QSPI bus access function by platform data
- move synchronous mode as a fdt parameter
- reorganizing defines in proper patches
- fix make dt_binding_check errors
- fix ad3552r maximum SPI speed
- fix samplerate calulcation
- minor code style fixes

Changes in v4:
- fix Kconfig
- fix backend documentation
- driver renamed to a more gneric "high speed" (ad3552r-hs)
- restyled axi-dac register names
- removed synchronous support, dead code
  (could be added in the future with David sugestions if needed)
- renaming backend buffer enable/disable calls
- using model_data in common code
- using devm_add_action_or_reset
- minor code style fixes

Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>

---
Angelo Dureghello (11):
      iio: dac: adi-axi-dac: update register names
      iio: dac: adi-axi-dac: fix wrong register bitfield
      dt-bindings: iio: dac: adi-axi-dac: add ad3552r axi variant
      dt-bindings: iio: dac: ad3552r: fix maximum spi speed
      dt-bindings: iio: dac: ad3552r: add iio backend support
      iio: backend: extend features
      iio: dac: adi-axi-dac: extend features
      iio: dac: ad3552r: changes to use FIELD_PREP
      iio: dac: ad3552r: extract common code (no changes in behavior intended)
      iio: dac: ad3552r: add high-speed platform driver
      iio: dac: adi-axi-dac: add registering of child fdt node

 .../devicetree/bindings/iio/dac/adi,ad3552r.yaml   |   9 +-
 .../devicetree/bindings/iio/dac/adi,axi-dac.yaml   |  49 +-
 drivers/iio/dac/Kconfig                            |  14 +
 drivers/iio/dac/Makefile                           |   3 +-
 drivers/iio/dac/ad3552r-common.c                   | 170 +++++++
 drivers/iio/dac/ad3552r-hs.c                       | 528 +++++++++++++++++++++
 drivers/iio/dac/ad3552r.c                          | 461 +++---------------
 drivers/iio/dac/ad3552r.h                          | 207 ++++++++
 drivers/iio/dac/adi-axi-dac.c                      | 477 ++++++++++++++++---
 drivers/iio/industrialio-backend.c                 |  79 +++
 include/linux/iio/backend.h                        |  17 +
 include/linux/platform_data/ad3552r-hs.h           |  18 +
 12 files changed, 1563 insertions(+), 469 deletions(-)
---
base-commit: c81ca31b5191ef48b5e5fb2545fde7dd436c2bd5
change-id: 20241003-wip-bl-ad3552r-axi-v0-iio-testing-aedec3e91ff7

Best regards,
-- 
Angelo Dureghello <adureghello@baylibre.com>

[PATCH v4 02/11] iio: dac: adi-axi-dac: fix wrong register bitfield

[Angelo Dureghello]

From: Angelo Dureghello <adureghello@baylibre.com>

Fix ADI_DAC_R1_MODE of AXI_DAC_REG_CNTRL_2.

Both generic DAC and ad3552r DAC IPs docs are reporting
bit 5 for it.

Link: https://wiki.analog.com/resources/fpga/docs/axi_dac_ip
Fixes: 4e3949a192e4 ("iio: dac: add support for AXI DAC IP core")
Cc: stable@vger.kernel.org
Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
---
 drivers/iio/dac/adi-axi-dac.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/dac/adi-axi-dac.c b/drivers/iio/dac/adi-axi-dac.c
index e83f70465b46..04193a98616e 100644
--- a/drivers/iio/dac/adi-axi-dac.c
+++ b/drivers/iio/dac/adi-axi-dac.c
@@ -46,7 +46,7 @@
 #define AXI_DAC_CNTRL_1_REG			0x0044
 #define   AXI_DAC_CNTRL_1_SYNC			BIT(0)
 #define AXI_DAC_CNTRL_2_REG			0x0048
-#define   ADI_DAC_CNTRL_2_R1_MODE		BIT(4)
+#define   ADI_DAC_CNTRL_2_R1_MODE		BIT(5)
 #define AXI_DAC_DRP_STATUS_REG			0x0074
 #define   AXI_DAC_DRP_STATUS_DRP_LOCKED		BIT(17)
 

-- 
2.45.0.rc1

[PATCH v4 04/11] dt-bindings: iio: dac: ad3552r: fix maximum spi speed

[Angelo Dureghello]

From: Angelo Dureghello <adureghello@baylibre.com>

Fix maximum SPI clock speed, as per datasheet (Rev. B, page 6).

Fixes: b0a96c5f599e ("dt-bindings: iio: dac: Add adi,ad3552r.yaml")
Cc: stable@vger.kernel.org
Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
---
 Documentation/devicetree/bindings/iio/dac/adi,ad3552r.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/iio/dac/adi,ad3552r.yaml b/Documentation/devicetree/bindings/iio/dac/adi,ad3552r.yaml
index fc8b97f82077..41fe00034742 100644
--- a/Documentation/devicetree/bindings/iio/dac/adi,ad3552r.yaml
+++ b/Documentation/devicetree/bindings/iio/dac/adi,ad3552r.yaml
@@ -30,7 +30,7 @@ properties:
     maxItems: 1
 
   spi-max-frequency:
-    maximum: 30000000
+    maximum: 66000000
 
   reset-gpios:
     maxItems: 1

-- 
2.45.0.rc1

Re: [PATCH v4 04/11] dt-bindings: iio: dac: ad3552r: fix maximum spi speed

[Krzysztof Kozlowski]

On Thu, Oct 03, 2024 at 07:29:01PM +0200, Angelo Dureghello wrote:
> From: Angelo Dureghello <adureghello@baylibre.com>
> 
> Fix maximum SPI clock speed, as per datasheet (Rev. B, page 6).
> 
> Fixes: b0a96c5f599e ("dt-bindings: iio: dac: Add adi,ad3552r.yaml")
> Cc: stable@vger.kernel.org
> Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof

Re: [PATCH v4 02/11] iio: dac: adi-axi-dac: fix wrong register bitfield

[Jonathan Cameron]

On Thu, 03 Oct 2024 19:28:59 +0200
Angelo Dureghello <adureghello@baylibre.com> wrote:

> From: Angelo Dureghello <adureghello@baylibre.com>
> 
> Fix ADI_DAC_R1_MODE of AXI_DAC_REG_CNTRL_2.
> 
> Both generic DAC and ad3552r DAC IPs docs are reporting
> bit 5 for it.

Reorder to come before the previous patch.
This want's backporting. The renames are good but too noisy to
backport if we can avoid it.

Jonathan

> 
> Link: https://wiki.analog.com/resources/fpga/docs/axi_dac_ip
> Fixes: 4e3949a192e4 ("iio: dac: add support for AXI DAC IP core")
> Cc: stable@vger.kernel.org
> Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
> Reviewed-by: Nuno Sa <nuno.sa@analog.com>
> ---
>  drivers/iio/dac/adi-axi-dac.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/dac/adi-axi-dac.c b/drivers/iio/dac/adi-axi-dac.c
> index e83f70465b46..04193a98616e 100644
> --- a/drivers/iio/dac/adi-axi-dac.c
> +++ b/drivers/iio/dac/adi-axi-dac.c
> @@ -46,7 +46,7 @@
>  #define AXI_DAC_CNTRL_1_REG			0x0044
>  #define   AXI_DAC_CNTRL_1_SYNC			BIT(0)
>  #define AXI_DAC_CNTRL_2_REG			0x0048
> -#define   ADI_DAC_CNTRL_2_R1_MODE		BIT(4)
> +#define   ADI_DAC_CNTRL_2_R1_MODE		BIT(5)
>  #define AXI_DAC_DRP_STATUS_REG			0x0074
>  #define   AXI_DAC_DRP_STATUS_DRP_LOCKED		BIT(17)
>  
> 

Re: [PATCH v4 04/11] dt-bindings: iio: dac: ad3552r: fix maximum spi speed

[Jonathan Cameron]

On Thu, 03 Oct 2024 19:29:01 +0200
Angelo Dureghello <adureghello@baylibre.com> wrote:

> From: Angelo Dureghello <adureghello@baylibre.com>
> 
> Fix maximum SPI clock speed, as per datasheet (Rev. B, page 6).
> 
> Fixes: b0a96c5f599e ("dt-bindings: iio: dac: Add adi,ad3552r.yaml")
> Cc: stable@vger.kernel.org
> Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
I'm going to take this the slow way as it probably doesn't affect any
existing DTS so can wait a while and taking it via the fixes
branch would slow down the rest of the series.

I am keen though to cut down how many patches are in revisions
though so I've picked this one up today. Please rebase on
my tree before sending v5 to pick this up.

Applied to the togreg branch of iio.git

Thanks,
Jonathan
> ---
>  Documentation/devicetree/bindings/iio/dac/adi,ad3552r.yaml | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/iio/dac/adi,ad3552r.yaml b/Documentation/devicetree/bindings/iio/dac/adi,ad3552r.yaml
> index fc8b97f82077..41fe00034742 100644
> --- a/Documentation/devicetree/bindings/iio/dac/adi,ad3552r.yaml
> +++ b/Documentation/devicetree/bindings/iio/dac/adi,ad3552r.yaml
> @@ -30,7 +30,7 @@ properties:
>      maxItems: 1
>  
>    spi-max-frequency:
> -    maximum: 30000000
> +    maximum: 66000000
>  
>    reset-gpios:
>      maxItems: 1
>