[PATCH v5 0/4] LogiCVC mfd and GPIO support

[PATCH v5 0/4] LogiCVC mfd and GPIO support

[Paul Kocialkowski]

This series introduces support for the LogiCVC GPIO block to the syscon GPIO
driver, with dt bindings documentation also including the top-level mfd
component.

Changes since v4:
- Moved the GPIO driver to a dedicated driver.

Changes since v3:
- Added collected tags;
- Kept syscon_gpio_data set function pointer line intact;
- Grouped declarations in a single line as requested.

Changes since v2:
- Fixed dt schema examples.

Changes since v1:
- Converted dt bindings documentation to dt schemas;
- Used BIT macro and removed version from structure name;
- Improved documentation example with gpio-line-names;
- Added vendor prefix to dt bindings;
- Added mfd component dt bindings documentation.

Cheers,

Paul

Paul Kocialkowski (4):
  dt-bindings: Add Xylon vendor prefix
  dt-bindings: mfd: Document the Xylon LogiCVC multi-function device
  dt-bindings: gpio: Document the Xylon LogiCVC GPIO controller
  gpio: Add support for the Xylon LogiCVC GPIOs

 .../bindings/gpio/xylon,logicvc-gpio.yaml     |  69 +++++++
 .../bindings/mfd/xylon,logicvc.yaml           |  50 ++++++
 .../devicetree/bindings/vendor-prefixes.yaml  |   2 +
 drivers/gpio/Kconfig                          |   6 +
 drivers/gpio/Makefile                         |   1 +
 drivers/gpio/gpio-logicvc.c                   | 170 ++++++++++++++++++
 6 files changed, 298 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/gpio/xylon,logicvc-gpio.yaml
 create mode 100644 Documentation/devicetree/bindings/mfd/xylon,logicvc.yaml
 create mode 100644 drivers/gpio/gpio-logicvc.c

-- 
2.24.0

[PATCH v5 1/4] dt-bindings: Add Xylon vendor prefix

[Paul Kocialkowski]

Xylon is an electronics company that produces FPGA hardware block designs
optimized for Xilinx FPGAs.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Acked-by: Rob Herring <robh@kernel.org>
---
 Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/vendor-prefixes.yaml b/Documentation/devicetree/bindings/vendor-prefixes.yaml
index 967e78c5ec0a..62bbde20ff5e 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.yaml
+++ b/Documentation/devicetree/bindings/vendor-prefixes.yaml
@@ -1054,6 +1054,8 @@ patternProperties:
     description: Xilinx
   "^xunlong,.*":
     description: Shenzhen Xunlong Software CO.,Limited
+  "^xylon,.*":
+    description: Xylon
   "^yones-toptech,.*":
     description: Yones Toptech Co., Ltd.
   "^ysoft,.*":
-- 
2.24.0

Re: [PATCH v5 1/4] dt-bindings: Add Xylon vendor prefix

[Linus Walleij]

On Tue, Dec 3, 2019 at 3:13 PM Paul Kocialkowski
<paul.kocialkowski@bootlin.com> wrote:

> Xylon is an electronics company that produces FPGA hardware block designs
> optimized for Xilinx FPGAs.
>
> Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
> Acked-by: Rob Herring <robh@kernel.org>

Patch applied to the GPIO tree.

Yours,
Linus Walleij

[PATCH v5 2/4] dt-bindings: mfd: Document the Xylon LogiCVC multi-function device

[Paul Kocialkowski]

The LogiCVC is a display engine which also exposes GPIO functionality.
For this reason, it is described as a multi-function device that is expected
to provide register access to its children nodes for gpio and display.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---
 .../bindings/mfd/xylon,logicvc.yaml           | 50 +++++++++++++++++++
 1 file changed, 50 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mfd/xylon,logicvc.yaml

diff --git a/Documentation/devicetree/bindings/mfd/xylon,logicvc.yaml b/Documentation/devicetree/bindings/mfd/xylon,logicvc.yaml
new file mode 100644
index 000000000000..abc9937506e0
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/xylon,logicvc.yaml
@@ -0,0 +1,50 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+# Copyright 2019 Bootlin
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/mfd/xylon,logicvc.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Xylon LogiCVC multi-function device
+
+maintainers:
+  - Paul Kocialkowski <paul.kocialkowski@bootlin.com>
+
+description: |
+  The LogiCVC is a display controller that also contains a GPIO controller.
+  As a result, a multi-function device is exposed as parent of the display
+  and GPIO blocks.
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - xylon,logicvc-3.02.a
+      - const: syscon
+      - const: simple-mfd
+
+  reg:
+    maxItems: 1
+
+select:
+  properties:
+    compatible:
+      contains:
+        enum:
+          - xylon,logicvc-3.02.a
+
+  required:
+    - compatible
+
+required:
+  - compatible
+  - reg
+
+examples:
+  - |
+    logicvc: logicvc@43c00000 {
+      compatible = "xylon,logicvc-3.02.a", "syscon", "simple-mfd";
+      reg = <0x43c00000 0x6000>;
+      #address-cells = <1>;
+      #size-cells = <1>;
+    };
-- 
2.24.0

Re: [PATCH v5 2/4] dt-bindings: mfd: Document the Xylon LogiCVC multi-function device

[Linus Walleij]

On Tue, Dec 3, 2019 at 3:13 PM Paul Kocialkowski
<paul.kocialkowski@bootlin.com> wrote:

> The LogiCVC is a display engine which also exposes GPIO functionality.
> For this reason, it is described as a multi-function device that is expected
> to provide register access to its children nodes for gpio and display.
>
> Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
> Reviewed-by: Rob Herring <robh@kernel.org>

Patch applied to the GPIO tree unless Lee has objections.

Yours,
Linus Walleij

Re: [PATCH v5 2/4] dt-bindings: mfd: Document the Xylon LogiCVC multi-function device

[Lee Jones]

On Fri, 13 Dec 2019, Linus Walleij wrote:

> On Tue, Dec 3, 2019 at 3:13 PM Paul Kocialkowski
> <paul.kocialkowski@bootlin.com> wrote:
> 
> > The LogiCVC is a display engine which also exposes GPIO functionality.
> > For this reason, it is described as a multi-function device that is expected
> > to provide register access to its children nodes for gpio and display.
> >
> > Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
> > Reviewed-by: Rob Herring <robh@kernel.org>
> 
> Patch applied to the GPIO tree unless Lee has objections.

Seeing as it's you ...

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

[PATCH v5 3/4] dt-bindings: gpio: Document the Xylon LogiCVC GPIO controller

[Paul Kocialkowski]

The Xylon LogiCVC display controller exports some GPIOs, which are
exposed as a separate entity.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---
 .../bindings/gpio/xylon,logicvc-gpio.yaml     | 69 +++++++++++++++++++
 1 file changed, 69 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/gpio/xylon,logicvc-gpio.yaml

diff --git a/Documentation/devicetree/bindings/gpio/xylon,logicvc-gpio.yaml b/Documentation/devicetree/bindings/gpio/xylon,logicvc-gpio.yaml
new file mode 100644
index 000000000000..d102888c1be7
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/xylon,logicvc-gpio.yaml
@@ -0,0 +1,69 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+# Copyright 2019 Bootlin
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/gpio/xylon,logicvc-gpio.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Xylon LogiCVC GPIO controller
+
+maintainers:
+  - Paul Kocialkowski <paul.kocialkowski@bootlin.com>
+
+description: |
+  The LogiCVC GPIO describes the GPIO block included in the LogiCVC display
+  controller. These are meant to be used for controlling display-related
+  signals.
+
+  The controller exposes GPIOs from the display and power control registers,
+  which are mapped by the driver as follows:
+  - GPIO[4:0] (display control) mapped to index 0-4
+  - EN_BLIGHT (power control) mapped to index 5
+  - EN_VDD (power control) mapped to index 6
+  - EN_VEE (power control) mapped to index 7
+  - V_EN (power control) mapped to index 8
+
+properties:
+  $nodename:
+    pattern: "^gpio@[0-9a-f]+$"
+
+  compatible:
+    enum:
+      - xylon,logicvc-3.02.a-gpio
+
+  reg:
+    maxItems: 1
+
+  "#gpio-cells":
+    const: 2
+
+  gpio-controller: true
+
+  gpio-line-names:
+    minItems: 1
+    maxItems: 9
+
+required:
+  - compatible
+  - reg
+  - "#gpio-cells"
+  - gpio-controller
+
+examples:
+  - |
+    logicvc: logicvc@43c00000 {
+      compatible = "xylon,logicvc-3.02.a", "syscon", "simple-mfd";
+      reg = <0x43c00000 0x6000>;
+
+      #address-cells = <1>;
+      #size-cells = <1>;
+
+      logicvc_gpio: gpio@40 {
+        compatible = "xylon,logicvc-3.02.a-gpio";
+        reg = <0x40 0x40>;
+        gpio-controller;
+        #gpio-cells = <2>;
+        gpio-line-names = "GPIO0", "GPIO1", "GPIO2", "GPIO3", "GPIO4",
+               "EN_BLIGHT", "EN_VDD", "EN_VEE", "V_EN";
+      };
+    };
-- 
2.24.0

Re: [PATCH v5 3/4] dt-bindings: gpio: Document the Xylon LogiCVC GPIO controller

[Linus Walleij]

On Tue, Dec 3, 2019 at 3:13 PM Paul Kocialkowski
<paul.kocialkowski@bootlin.com> wrote:

> The Xylon LogiCVC display controller exports some GPIOs, which are
> exposed as a separate entity.
>
> Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
> Reviewed-by: Rob Herring <robh@kernel.org>

Patch applied.

Yours,
Linus Walleij

[PATCH v5 4/4] gpio: Add support for the Xylon LogiCVC GPIOs

[Paul Kocialkowski]

The LogiCVC display hardware block comes with GPIO capabilities
that must be exposed separately from the main driver (as GPIOs) for
use with regulators and panels. A syscon is used to share the same
regmap across the two drivers.

Add a minimalistic GPIO driver to drive these GPIOs, using a syscon
regmap when available.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
---
 drivers/gpio/Kconfig        |   6 ++
 drivers/gpio/Makefile       |   1 +
 drivers/gpio/gpio-logicvc.c | 170 ++++++++++++++++++++++++++++++++++++
 3 files changed, 177 insertions(+)
 create mode 100644 drivers/gpio/gpio-logicvc.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index e9516393c971..3b0a8cfc5f17 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -312,6 +312,12 @@ config GPIO_IXP4XX
 	  IXP4xx series of chips.
 
 	  If unsure, say N.
+config GPIO_LOGICVC
+	tristate "Xylon LogiCVC GPIO support"
+	depends on MFD_SYSCON && OF
+	help
+	  Say yes here to support GPIO functionality of the Xylon LogiCVC
+	  programmable logic block.
 
 config GPIO_LOONGSON
 	bool "Loongson-2/3 GPIO support"
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 34eb8b2b12dd..ba53f1fcde3a 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -69,6 +69,7 @@ obj-$(CONFIG_GPIO_IT87)			+= gpio-it87.o
 obj-$(CONFIG_GPIO_IXP4XX)		+= gpio-ixp4xx.o
 obj-$(CONFIG_GPIO_JANZ_TTL)		+= gpio-janz-ttl.o
 obj-$(CONFIG_GPIO_KEMPLD)		+= gpio-kempld.o
+obj-$(CONFIG_GPIO_LOGICVC)		+= gpio-logicvc.o
 obj-$(CONFIG_GPIO_LOONGSON1)		+= gpio-loongson1.o
 obj-$(CONFIG_GPIO_LOONGSON)		+= gpio-loongson.o
 obj-$(CONFIG_GPIO_LP3943)		+= gpio-lp3943.o
diff --git a/drivers/gpio/gpio-logicvc.c b/drivers/gpio/gpio-logicvc.c
new file mode 100644
index 000000000000..015632cf159f
--- /dev/null
+++ b/drivers/gpio/gpio-logicvc.c
@@ -0,0 +1,170 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2019 Bootlin
+ * Author: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
+ */
+
+#include <linux/err.h>
+#include <linux/gpio/driver.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+
+#define LOGICVC_CTRL_REG		0x40
+#define LOGICVC_CTRL_GPIO_SHIFT		11
+#define LOGICVC_CTRL_GPIO_BITS		5
+
+#define LOGICVC_POWER_CTRL_REG		0x78
+#define LOGICVC_POWER_CTRL_GPIO_SHIFT	0
+#define LOGICVC_POWER_CTRL_GPIO_BITS	4
+
+struct logicvc_gpio {
+	struct gpio_chip chip;
+	struct regmap *regmap;
+};
+
+static void logicvc_gpio_offset(struct logicvc_gpio *logicvc, unsigned offset,
+				unsigned int *reg, unsigned int *bit)
+{
+	if (offset >= LOGICVC_CTRL_GPIO_BITS) {
+		*reg = LOGICVC_POWER_CTRL_REG;
+
+		/* To the (virtual) power ctrl offset. */
+		offset -= LOGICVC_CTRL_GPIO_BITS;
+		/* To the actual bit offset in reg. */
+		offset += LOGICVC_POWER_CTRL_GPIO_SHIFT;
+	} else {
+		*reg = LOGICVC_CTRL_REG;
+
+		/* To the actual bit offset in reg. */
+		offset += LOGICVC_CTRL_GPIO_SHIFT;
+	}
+
+	*bit = BIT(offset);
+}
+
+static int logicvc_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+	struct logicvc_gpio *logicvc = gpiochip_get_data(chip);
+	unsigned int reg, bit, value;
+	int ret;
+
+	logicvc_gpio_offset(logicvc, offset, &reg, &bit);
+
+	ret = regmap_read(logicvc->regmap, reg, &value);
+	if (ret)
+		return ret;
+
+	return !!(value & bit);
+}
+
+static void logicvc_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+	struct logicvc_gpio *logicvc = gpiochip_get_data(chip);
+	unsigned int reg, bit;
+
+	logicvc_gpio_offset(logicvc, offset, &reg, &bit);
+
+	regmap_update_bits(logicvc->regmap, reg, bit, value ? bit : 0);
+}
+
+static int logicvc_gpio_direction_output(struct gpio_chip *chip,
+					 unsigned offset, int value)
+{
+	/* Pins are always configured as output, so just set the value. */
+	logicvc_gpio_set(chip, offset, value);
+
+	return 0;
+}
+
+static struct regmap_config logicvc_gpio_regmap_config = {
+	.reg_bits	= 32,
+	.val_bits	= 32,
+	.reg_stride	= 4,
+	.name		= "logicvc-gpio",
+};
+
+static int logicvc_gpio_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *of_node = dev->of_node;
+	struct logicvc_gpio *logicvc;
+	int ret;
+
+	logicvc = devm_kzalloc(dev, sizeof(*logicvc), GFP_KERNEL);
+	if (!logicvc)
+		return -ENOMEM;
+
+	/* Try to get regmap from parent first. */
+	logicvc->regmap = syscon_node_to_regmap(of_node->parent);
+
+	/* Grab our own regmap if that fails. */
+	if (IS_ERR(logicvc->regmap)) {
+		struct resource res;
+		void __iomem *base;
+
+		ret = of_address_to_resource(of_node, 0, &res);
+		if (ret) {
+			dev_err(dev, "Failed to get resource from address\n");
+			return ret;
+		}
+
+		base = devm_ioremap_resource(dev, &res);
+		if (IS_ERR(base)) {
+			dev_err(dev, "Failed to map I/O base\n");
+			return PTR_ERR(base);
+		}
+
+		logicvc_gpio_regmap_config.max_register = resource_size(&res) -
+			logicvc_gpio_regmap_config.reg_stride;
+
+		logicvc->regmap =
+			devm_regmap_init_mmio(dev, base,
+					      &logicvc_gpio_regmap_config);
+		if (IS_ERR(logicvc->regmap)) {
+			dev_err(dev, "Failed to create regmap for I/O\n");
+			return PTR_ERR(logicvc->regmap);
+		}
+	}
+
+	logicvc->chip.parent = dev;
+	logicvc->chip.owner = THIS_MODULE;
+	logicvc->chip.label = dev_name(dev);
+	logicvc->chip.base = -1;
+	logicvc->chip.ngpio = LOGICVC_CTRL_GPIO_BITS +
+			      LOGICVC_POWER_CTRL_GPIO_BITS;
+	logicvc->chip.get = logicvc_gpio_get;
+	logicvc->chip.set = logicvc_gpio_set;
+	logicvc->chip.direction_output = logicvc_gpio_direction_output;
+
+	platform_set_drvdata(pdev, logicvc);
+
+	return devm_gpiochip_add_data(dev, &logicvc->chip, logicvc);
+}
+
+static const struct of_device_id logicivc_gpio_of_table[] = {
+	{
+		.compatible	= "xylon,logicvc-3.02.a-gpio",
+	},
+	{ }
+};
+
+MODULE_DEVICE_TABLE(of, logicivc_gpio_of_table);
+
+static struct platform_driver logicvc_gpio_driver = {
+	.driver	= {
+		.name		= "gpio-logicvc",
+		.of_match_table	= logicivc_gpio_of_table,
+	},
+	.probe	= logicvc_gpio_probe,
+};
+
+module_platform_driver(logicvc_gpio_driver);
+
+MODULE_AUTHOR("Paul Kocialkowski <paul.kocialkowski@bootlin.com>");
+MODULE_DESCRIPTION("Xylon LogiCVC GPIO driver");
+MODULE_LICENSE("GPL");
-- 
2.24.0

Re: [PATCH v5 4/4] gpio: Add support for the Xylon LogiCVC GPIOs

[Linus Walleij]

On Tue, Dec 3, 2019 at 3:13 PM Paul Kocialkowski
<paul.kocialkowski@bootlin.com> wrote:

> The LogiCVC display hardware block comes with GPIO capabilities
> that must be exposed separately from the main driver (as GPIOs) for
> use with regulators and panels. A syscon is used to share the same
> regmap across the two drivers.
>
> Add a minimalistic GPIO driver to drive these GPIOs, using a syscon
> regmap when available.
>
> Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>

Patch applied.

Yours,
Linus Walleij