[PATCH v4 1/6] mfd: fsl imx25 Touchscreen ADC driver

Subsystems: multifunction devices (mfd), open firmware and flattened device tree bindings, the rest

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3 messages, 2 authors, 2014-06-24 · open the first message on its own page

[PATCH v4 1/6] mfd: fsl imx25 Touchscreen ADC driver

From: Denis Carikli <hidden>
Date: 2014-06-24 14:46:30

From: Markus Pargmann <redacted>

This is the core driver for imx25 touchscreen/adc driver. The module
has one shared ADC and two different conversion queues which use the
ADC. The two queues are identical. Both can be used for general purpose
ADC but one is meant to be used for touchscreens.

This driver is the core which manages the central components and
registers of the TSC/ADC unit. It manages the IRQs and forwards them to
the correct components.

Signed-off-by: Markus Pargmann <redacted>
Signed-off-by: Denis Carikli <redacted>
Acked-by: Jonathan Cameron <redacted>
---
Changelog v3->v4:
- Added Jonathan's Ack
- ARCH_MXC Kconfigdependency removed.
- mx25_tsadc_get_regmap and mx25_tsadc_get_ipg contents have been moved
  in the caller function.
- mx25_tsadc_irq_chip has been removed.
- Register definitions are now more humain readable.
- Many other code and style cleanups.

Changelog v2->v3:
- None
---
 .../devicetree/bindings/mfd/fsl-imx25-tsadc.txt    |   46 ++++++
 drivers/mfd/Kconfig                                |    8 +
 drivers/mfd/Makefile                               |    2 +
 drivers/mfd/fsl-imx25-tsadc.c                      |  170 ++++++++++++++++++++
 include/linux/mfd/imx25-tsadc.h                    |  140 ++++++++++++++++
 5 files changed, 366 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mfd/fsl-imx25-tsadc.txt
 create mode 100644 drivers/mfd/fsl-imx25-tsadc.c
 create mode 100644 include/linux/mfd/imx25-tsadc.h
diff --git a/Documentation/devicetree/bindings/mfd/fsl-imx25-tsadc.txt b/Documentation/devicetree/bindings/mfd/fsl-imx25-tsadc.txt
new file mode 100644
index 0000000..a857af0e
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/fsl-imx25-tsadc.txt
@@ -0,0 +1,46 @@
+Freescale mx25 ADC/TSC multifunction device
+
+This device combines two general purpose conversion queues one used for general
+ADC and the other used for touchscreens.
+
+Required properties:
+ - compatible: Should be "fsl,imx25-tsadc".
+ - reg: Memory range of the device.
+ - interrupts: Interrupt for this device as described in
+   interrupts/interrupts.txt
+ - clocks: An 'ipg' clock defined as described in clocks/clock.txt
+ - interrupt-controller: This device is an interrupt controller. It controls
+   the interrupts of both conversion queues.
+ - #interrupt-cells: Should be '<1>'.
+ - #address-cells: Should be '<1>'.
+ - #size-cells: Should be '<1>'.
+ - ranges
+
+This device includes two conversion queues which can be added as subnodes.
+The first queue is for the touchscreen, the second for general purpose ADC.
+
+Example:
+	tscadc: tscadc@50030000 {
+		compatible = "fsl,imx25-tsadc";
+		reg = <0x50030000 0xc>;
+		interrupts = <46>;
+		clocks = <&clks 119>;
+		clock-names = "ipg";
+		interrupt-controller;
+		#interrupt-cells = <1>;
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges;
+
+		tsc: tcq@50030400 {
+			compatible = "fsl,imx25-tcq";
+			reg = <0x50030400 0x60>;
+			...
+		};
+
+		adc: gcq@50030800 {
+			compatible = "fsl,imx25-gcq";
+			reg = <0x50030800 0x60>;
+			...
+		};
+	};
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index af0e83f..d354547 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -183,6 +183,14 @@ config MFD_DA9063
 	  Additional drivers must be enabled in order to use the functionality
 	  of the device.
 
+config MFD_MX25_TSADC
+	tristate "Freescale i.MX25 integrated Touchscreen and ADC unit"
+	select REGMAP_MMIO
+	help
+	  Enable support for the integrated Touchscreen and ADC unit of the
+	  i.MX25 processors. They consist of a conversion queue for general
+	  purpose ADC and a queue for Touchscreens.
+
 config MFD_MC13XXX
 	tristate
 	depends on (SPI_MASTER || I2C)
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 4e2bc25..34388c4 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -78,6 +78,8 @@ obj-$(CONFIG_TWL4030_POWER)    += twl4030-power.o
 obj-$(CONFIG_MFD_TWL4030_AUDIO)	+= twl4030-audio.o
 obj-$(CONFIG_TWL6040_CORE)	+= twl6040.o
 
+obj-$(CONFIG_MFD_MX25_TSADC)	+= fsl-imx25-tsadc.o
+
 obj-$(CONFIG_MFD_MC13XXX)	+= mc13xxx-core.o
 obj-$(CONFIG_MFD_MC13XXX_SPI)	+= mc13xxx-spi.o
 obj-$(CONFIG_MFD_MC13XXX_I2C)	+= mc13xxx-i2c.o
diff --git a/drivers/mfd/fsl-imx25-tsadc.c b/drivers/mfd/fsl-imx25-tsadc.c
new file mode 100644
index 0000000..cebc291
--- /dev/null
+++ b/drivers/mfd/fsl-imx25-tsadc.c
@@ -0,0 +1,170 @@
+/*
+ * Copyright 2014 Markus Pargmann, Pengutronix <mpa-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqdesc.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/mfd/imx25-tsadc.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+static struct regmap_config mx25_tsadc_regmap_config = {
+	.fast_io = true,
+	.max_register = 8,
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+};
+
+static void mx25_tsadc_irq_handler(u32 irq, struct irq_desc *desc)
+{
+	struct mx25_tsadc *tsadc = irq_desc_get_handler_data(desc);
+	struct irq_chip *chip = irq_get_chip(irq);
+	u32 status;
+
+	chained_irq_enter(chip, desc);
+
+	regmap_read(tsadc->regs, MX25_TSC_TGSR, &status);
+
+	if (status & MX25_TGSR_GCQ_INT)
+		generic_handle_irq(irq_find_mapping(tsadc->domain, 1));
+
+	if (status & MX25_TGSR_TCQ_INT)
+		generic_handle_irq(irq_find_mapping(tsadc->domain, 0));
+
+	chained_irq_exit(chip, desc);
+}
+
+static int mx25_tsadc_domain_map(struct irq_domain *d, unsigned int irq,
+			     irq_hw_number_t hwirq)
+{
+	struct mx25_tsadc *tsadc = d->host_data;
+
+	irq_set_chip_data(irq, tsadc);
+	irq_set_chip_and_handler(irq, &dummy_irq_chip,
+				 handle_level_irq);
+	set_irq_flags(irq, IRQF_VALID);
+
+	return 0;
+}
+
+static struct irq_domain_ops mx25_tsadc_domain_ops = {
+	.map = mx25_tsadc_domain_map,
+	.xlate = irq_domain_xlate_onecell,
+};
+
+static int mx25_tsadc_setup_irq(struct platform_device *pdev,
+		struct mx25_tsadc *tsadc)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	int irq;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(dev, "Failed to get irq\n");
+		return irq;
+	}
+
+	tsadc->domain = irq_domain_add_simple(np, 2, 0, &mx25_tsadc_domain_ops,
+			tsadc);
+	if (!tsadc->domain) {
+		dev_err(dev, "Failed to add irq domain\n");
+		return -ENOMEM;
+	}
+
+	irq_set_chained_handler(irq, mx25_tsadc_irq_handler);
+	irq_set_handler_data(irq, tsadc);
+
+	return 0;
+}
+
+static int mx25_tsadc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct mx25_tsadc *tsadc;
+	struct resource *res;
+	int ret;
+	void __iomem *iomem;
+
+	tsadc = devm_kzalloc(dev, sizeof(*tsadc), GFP_KERNEL);
+	if (!tsadc)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	iomem = devm_ioremap_resource(dev, res);
+	if (IS_ERR(iomem))
+		return PTR_ERR(iomem);
+
+	tsadc->regs = devm_regmap_init_mmio(dev, iomem,
+					    &mx25_tsadc_regmap_config);
+	if (IS_ERR(tsadc->regs)) {
+		dev_err(dev, "Failed to initialize regmap\n");
+		return PTR_ERR(tsadc->regs);
+	}
+
+	tsadc->clk = devm_clk_get(dev, "ipg");
+	if (IS_ERR(tsadc->clk)) {
+		dev_err(dev, "Failed to get ipg clock\n");
+		return PTR_ERR(tsadc->clk);
+	}
+
+	/* Enable clock and reset the component */
+	regmap_update_bits(tsadc->regs, MX25_TSC_TGCR, MX25_TGCR_CLK_EN,
+			MX25_TGCR_CLK_EN);
+	regmap_update_bits(tsadc->regs, MX25_TSC_TGCR, MX25_TGCR_TSC_RST,
+			MX25_TGCR_TSC_RST);
+
+	/* Setup powersaving mode, but enable internal reference voltage */
+	regmap_update_bits(tsadc->regs, MX25_TSC_TGCR, MX25_TGCR_POWERMODE_MASK,
+			MX25_TGCR_POWERMODE_SAVE);
+	regmap_update_bits(tsadc->regs, MX25_TSC_TGCR, MX25_TGCR_INTREFEN,
+			MX25_TGCR_INTREFEN);
+
+	ret = mx25_tsadc_setup_irq(pdev, tsadc);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, tsadc);
+
+	of_platform_populate(np, NULL, NULL, dev);
+
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id mx25_tsadc_ids[] = {
+	{ .compatible = "fsl,imx25-tsadc" },
+	{ /* Sentinel */ }
+};
+#endif
+
+static struct platform_driver mx25_tsadc_driver = {
+	.driver = {
+		.name = "mx25-tsadc",
+		.owner = THIS_MODULE,
+		.of_match_table = of_match_ptr(mx25_tsadc_ids),
+	},
+	.probe = mx25_tsadc_probe,
+};
+module_platform_driver(mx25_tsadc_driver);
+
+MODULE_DESCRIPTION("MFD for ADC/TSC for Freescale mx25");
+MODULE_AUTHOR("Markus Pargmann <mpa-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:mx25-tsadc");
diff --git a/include/linux/mfd/imx25-tsadc.h b/include/linux/mfd/imx25-tsadc.h
new file mode 100644
index 0000000..207dc7b
--- /dev/null
+++ b/include/linux/mfd/imx25-tsadc.h
@@ -0,0 +1,140 @@
+#ifndef _LINUX_INCLUDE_INPUT_IMX25_TSADC_H_
+#define _LINUX_INCLUDE_INPUT_IMX25_TSADC_H_
+
+struct regmap;
+struct device;
+struct clk;
+
+struct mx25_tsadc {
+	struct regmap *regs;
+	struct irq_domain *domain;
+	struct clk *clk;
+};
+
+#define MX25_TSC_TGCR			0x00
+#define MX25_TSC_TGSR			0x04
+#define MX25_TSC_TICR			0x08
+
+/* The same register layout for TC and GC queue */
+#define MX25_ADCQ_FIFO			0x00
+#define MX25_ADCQ_CR			0x04
+#define MX25_ADCQ_SR			0x08
+#define MX25_ADCQ_MR			0x0c
+#define MX25_ADCQ_ITEM_7_0		0x20
+#define MX25_ADCQ_ITEM_15_8		0x24
+#define MX25_ADCQ_CFG(n)		(0x40 + ((n) * 0x4))
+
+/* Register values */
+/* Queue Config register */
+#define MX25_ADCQ_MR_MASK		0xffffffff
+
+/* TGCR */
+#define MX25_TGCR_PDBTIME(x)		((x) << 25)
+#define MX25_TGCR_PDBTIME_MASK		MX25_TGCR_PDBTIME(0x7f)
+#define MX25_TGCR_PDBEN		BIT(24)
+#define MX25_TGCR_PDEN			BIT(23)
+#define MX25_TGCR_ADCCLKCFG(x)		((x) << 16)
+#define MX25_TGCR_GET_ADCCLK(x)	(((x) >> 16) & 0x1f)
+#define MX25_TGCR_INTREFEN		BIT(10)
+#define MX25_TGCR_POWERMODE_MASK	(3 << 8)
+#define MX25_TGCR_POWERMODE_SAVE	BIT(8)
+#define MX25_TGCR_POWERMODE_ON		(2 << 8)
+#define MX25_TGCR_STLC			BIT(5)
+#define MX25_TGCR_SLPC			BIT(4)
+#define MX25_TGCR_FUNC_RST		BIT(2)
+#define MX25_TGCR_TSC_RST		BIT(1)
+#define MX25_TGCR_CLK_EN		BIT(0)
+
+/* TGSR */
+#define MX25_TGSR_SLP_INT		BIT(2)
+#define MX25_TGSR_GCQ_INT		BIT(1)
+#define MX25_TGSR_TCQ_INT		BIT(0)
+
+/* ADCQ_ITEM_* */
+#define _MX25_ADCQ_ITEM(item, x)	((x) << ((item) * 4))
+#define MX25_ADCQ_ITEM(item, x)	((item) >= 8 ? \
+		_MX25_ADCQ_ITEM((item) - 8, (x)) : _MX25_ADCQ_ITEM((item), (x)))
+
+/* ADCQ_FIFO (TCQFIFO and GCQFIFO) */
+#define MX25_ADCQ_FIFO_DATA(x)		(((x) >> 4) & 0xfff)
+#define MX25_ADCQ_FIFO_ID(x)		((x) & 0xf)
+
+/* ADCQ_CR (TCQR and GCQR) */
+#define MX25_ADCQ_CR_PDCFG_LEVEL	BIT(19)
+#define MX25_ADCQ_CR_PDMSK		BIT(18)
+#define MX25_ADCQ_CR_FRST		BIT(17)
+#define MX25_ADCQ_CR_QRST		BIT(16)
+#define MX25_ADCQ_CR_RWAIT_MASK	(0xf << 12)
+#define MX25_ADCQ_CR_RWAIT(x)		((x) << 12)
+#define MX25_ADCQ_CR_WMRK_MASK		(0xf << 8)
+#define MX25_ADCQ_CR_WMRK(x)		((x) << 8)
+#define MX25_ADCQ_CR_LITEMID_MASK	(0xf << 4)
+#define MX25_ADCQ_CR_LITEMID(x)	((x) << 4)
+#define MX25_ADCQ_CR_RPT		BIT(3)
+#define MX25_ADCQ_CR_FQS		BIT(2)
+#define MX25_ADCQ_CR_QSM_MASK		0x3
+#define MX25_ADCQ_CR_QSM_PD		0x1
+#define MX25_ADCQ_CR_QSM_FQS		0x2
+#define MX25_ADCQ_CR_QSM_FQS_PD	0x3
+
+/* ADCQ_SR (TCQSR and GCQSR) */
+#define MX25_ADCQ_SR_FDRY		BIT(15)
+#define MX25_ADCQ_SR_FULL		BIT(14)
+#define MX25_ADCQ_SR_EMPT		BIT(13)
+#define MX25_ADCQ_SR_FDN(x)		(((x) >> 8) & 0x1f)
+#define MX25_ADCQ_SR_FRR		BIT(6)
+#define MX25_ADCQ_SR_FUR		BIT(5)
+#define MX25_ADCQ_SR_FOR		BIT(4)
+#define MX25_ADCQ_SR_EOQ		BIT(1)
+#define MX25_ADCQ_SR_PD		BIT(0)
+
+/* ADCQ_MR (TCQMR and GCQMR) */
+#define MX25_ADCQ_MR_FDRY_DMA		BIT(31)
+#define MX25_ADCQ_MR_FER_DMA		BIT(22)
+#define MX25_ADCQ_MR_FUR_DMA		BIT(21)
+#define MX25_ADCQ_MR_FOR_DMA		BIT(20)
+#define MX25_ADCQ_MR_EOQ_DMA		BIT(17)
+#define MX25_ADCQ_MR_PD_DMA		BIT(16)
+#define MX25_ADCQ_MR_FDRY_IRQ		BIT(15)
+#define MX25_ADCQ_MR_FER_IRQ		BIT(6)
+#define MX25_ADCQ_MR_FUR_IRQ		BIT(5)
+#define MX25_ADCQ_MR_FOR_IRQ		BIT(4)
+#define MX25_ADCQ_MR_EOQ_IRQ		BIT(1)
+#define MX25_ADCQ_MR_PD_IRQ		BIT(0)
+
+/* ADCQ_CFG (TICR, TCC0-7,GCC0-7) */
+#define MX25_ADCQ_CFG_SETTLING_TIME(x)	((x) << 24)
+#define MX25_ADCQ_CFG_IGS		BIT(20)
+#define MX25_ADCQ_CFG_NOS_MASK		(0xf << 16)
+#define MX25_ADCQ_CFG_NOS(x)		(((x) - 1) << 16)
+#define MX25_ADCQ_CFG_WIPER		BIT(15)
+#define MX25_ADCQ_CFG_YNLR		BIT(14)
+#define MX25_ADCQ_CFG_YPLL_HIGH	0
+#define MX25_ADCQ_CFG_YPLL_OFF		BIT(12)
+#define MX25_ADCQ_CFG_YPLL_LOW		(3 << 12)
+#define MX25_ADCQ_CFG_XNUR_HIGH	0
+#define MX25_ADCQ_CFG_XNUR_OFF		BIT(10)
+#define MX25_ADCQ_CFG_XNUR_LOW		(3 << 10)
+#define MX25_ADCQ_CFG_XPUL_OFF		BIT(9)
+#define MX25_ADCQ_CFG_XPUL_HIGH	0
+#define MX25_ADCQ_CFG_REFP_YP		0
+#define MX25_ADCQ_CFG_REFP_XP		BIT(7)
+#define MX25_ADCQ_CFG_REFP_EXT		(2 << 7)
+#define MX25_ADCQ_CFG_REFP_INT		(3 << 7)
+#define MX25_ADCQ_CFG_REFP_MASK	(3 << 7)
+#define MX25_ADCQ_CFG_IN_XP		0
+#define MX25_ADCQ_CFG_IN_YP		BIT(4)
+#define MX25_ADCQ_CFG_IN_XN		(2 << 4)
+#define MX25_ADCQ_CFG_IN_YN		(3 << 4)
+#define MX25_ADCQ_CFG_IN_WIPER		(4 << 4)
+#define MX25_ADCQ_CFG_IN_AUX0		(5 << 4)
+#define MX25_ADCQ_CFG_IN_AUX1		(6 << 4)
+#define MX25_ADCQ_CFG_IN_AUX2		(7 << 4)
+#define MX25_ADCQ_CFG_REFN_XN		0
+#define MX25_ADCQ_CFG_REFN_YN		BIT(2)
+#define MX25_ADCQ_CFG_REFN_NGND	(2 << 2)
+#define MX25_ADCQ_CFG_REFN_NGND2	(3 << 2)
+#define MX25_ADCQ_CFG_REFN_MASK	(3 << 2)
+#define MX25_ADCQ_CFG_PENIACK		BIT(1)
+
+#endif  /* _LINUX_INCLUDE_INPUT_IMX25_TSADC_H_ */
-- 
1.7.9.5

[PATCH v4 3/6] iio: adc: fsl,imx25-gcq driver

From: Denis Carikli <hidden>
Date: 2014-06-24 14:46:32

From: Markus Pargmann <redacted>

This is a conversion queue driver for the mx25 SoC. It uses the central
ADC which is used by two seperate independent queues. This driver
prepares different conversion configurations for each possible input.
For a conversion it creates a conversionqueue of one item with the
correct configuration for the chosen channel. It then executes the queue
once and disables the conversion queue afterwards.

The reference voltages are configurable through devicetree subnodes,
depending on the connections of the ADC inputs.

Signed-off-by: Markus Pargmann <redacted>
Signed-off-by: Denis Carikli <redacted>
---
Changelog v3->v4:
- Reworked the ADC reference voltage bindings.
- IIO_CHAN_INFO_SCALE is now handled.
- Lot of code and style cleanups.
- Tested by watching WIPER become 0 when the touchscreen is touched.

Changelog v2->v3:
- Fixed compilation: I forgott to tell that this IIO patch was untested
  in the previous cover letter. Now it is tested at runtime:
  I left the touchscreen connected but I configured the TSC as an ADC
  instead, set the refp to internal reference, and the refn to ngnd_adc(3)
  for the first 4 channels(xp,yp,xn,yn) and observed the values changing
  while touching the resistive 4-wire touchscreen.
- MX25_IIO_CHAN now became MX25_GCQ_CHAN and its .address is now gone
  and the code using it adapted.
- The instances of struct iio_dev were renamed from idev to indio_dev.
- regmap_read return value is now checked in mx25_gcq_read_raw.
- Comparisons with MX25_NUM_CFGS are now fixed
- Cosmetics fix in a multiline comment.
---
 .../devicetree/bindings/iio/adc/fsl,imx25-gcq.txt  |   51 +++
 drivers/iio/adc/Kconfig                            |    7 +
 drivers/iio/adc/Makefile                           |    1 +
 drivers/iio/adc/fsl-imx25-gcq.c                    |  371 ++++++++++++++++++++
 include/dt-bindings/iio/adc/fsl-imx25-gcq.h        |   11 +
 5 files changed, 441 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/adc/fsl,imx25-gcq.txt
 create mode 100644 drivers/iio/adc/fsl-imx25-gcq.c
 create mode 100644 include/dt-bindings/iio/adc/fsl-imx25-gcq.h
diff --git a/Documentation/devicetree/bindings/iio/adc/fsl,imx25-gcq.txt b/Documentation/devicetree/bindings/iio/adc/fsl,imx25-gcq.txt
new file mode 100644
index 0000000..e4a7170
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/fsl,imx25-gcq.txt
@@ -0,0 +1,51 @@
+Freescale i.MX25 ADC GCQ device
+
+This is a generic conversion queue device that can convert any of the
+analog inputs using the ADC unit of the i.MX25.
+
+Required properties:
+ - compatible: Should be "fsl,imx25-gcq".
+ - reg: Should be the register range of the module.
+ - interrupts: Should be the interrupt number of the module.
+   Typically this is <1>.
+ - interrupt-parent: phandle to the tsadc module of the i.MX25.
+ - #address-cells: Should be <1> (setting for the subnodes)
+ - #size-cells: Should be <0> (setting for the subnodes)
+
+Optional properties:
+ - vref-supply: The regulator supplying the ADC refrence voltage.
+   Required when at least one subnode uses the external reference.
+
+Sub-nodes:
+Optionally you can define subnodes which define the reference voltage
+for the analog inputs.
+
+Required properties for subnodes:
+ - reg: Should be the number of the analog input.
+     0: xp
+     1: yp
+     2: xn
+     3: yn
+     4: wiper
+     5: inaux0
+     6: inaux1
+     7: inaux2
+ - fsl,adc-ref: specifies the reference input as defined in
+     <dt-bindings/iio/adc/fsl-imx25-gcq.h>
+     MX25_ADC_REF_INT and MX25_ADC_REF_EXT flags are supported.
+
+Example:
+
+	adc: adc@50030800 {
+		compatible = "fsl,imx25-gcq";
+		reg = <0x50030800 0x60>;
+		interrupt-parent = <&tscadc>;
+		interrupts = <1>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		inaux@5 {
+			reg = <5>;
+			fsl,adc-ref = <MX25_ADC_REF_INT>;
+		};
+	};
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index a80d236..58efb8d 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -125,6 +125,13 @@ config EXYNOS_ADC
 	  of SoCs for drivers such as the touchscreen and hwmon to use to share
 	  this resource.
 
+config FSL_MX25_ADC
+	tristate "Freescale MX25 ADC driver"
+	depends on MFD_MX25_TSADC
+	help
+	  Generic Conversion Queue driver used for general purpose ADC in the
+	  MX25. This driver supports single measurements using the MX25 ADC.
+
 config LP8788_ADC
 	tristate "LP8788 ADC driver"
 	depends on MFD_LP8788
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 9d60f2d..2767fd6 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_AD7887) += ad7887.o
 obj-$(CONFIG_AD799X) += ad799x.o
 obj-$(CONFIG_AT91_ADC) += at91_adc.o
 obj-$(CONFIG_EXYNOS_ADC) += exynos_adc.o
+obj-$(CONFIG_FSL_MX25_ADC) += fsl-imx25-gcq.o
 obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o
 obj-$(CONFIG_MAX1363) += max1363.o
 obj-$(CONFIG_MCP320X) += mcp320x.o
diff --git a/drivers/iio/adc/fsl-imx25-gcq.c b/drivers/iio/adc/fsl-imx25-gcq.c
new file mode 100644
index 0000000..1e95553
--- /dev/null
+++ b/drivers/iio/adc/fsl-imx25-gcq.c
@@ -0,0 +1,371 @@
+/*
+ * Copyright 2014 Markus Pargmann, Pengutronix <mpa@pengutronix.de>
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * This is the driver for the imx25 GCQ (Generic Conversion Queue)
+ * connected to the imx25 ADC.
+ */
+
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/iio/iio.h>
+#include <linux/mfd/imx25-tsadc.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <dt-bindings/iio/adc/fsl-imx25-gcq.h>
+
+#define MX25_GCQ_TIMEOUT (msecs_to_jiffies(2000))
+
+enum mx25_gcq_cfgs {
+	MX25_CFG_XP = 0,
+	MX25_CFG_YP,
+	MX25_CFG_XN,
+	MX25_CFG_YN,
+	MX25_CFG_WIPER,
+	MX25_CFG_INAUX0,
+	MX25_CFG_INAUX1,
+	MX25_CFG_INAUX2,
+	MX25_NUM_CFGS,
+};
+
+struct mx25_gcq_priv {
+	struct regmap *regs;
+	struct completion completed;
+	unsigned int settling_time;
+	struct clk *clk;
+	int irq;
+	struct regulator *ext_vref;
+	u32 channel_vref_mv[MX25_NUM_CFGS];
+};
+
+#define MX25_CQG_CHAN(chan, id) {\
+	.type = IIO_VOLTAGE,\
+	.indexed = 1,\
+	.channel = chan,\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),\
+	.datasheet_name = id,\
+}
+
+static const struct iio_chan_spec mx25_gcq_channels[MX25_NUM_CFGS] = {
+	MX25_CQG_CHAN(0, "xp"),
+	MX25_CQG_CHAN(1, "yp"),
+	MX25_CQG_CHAN(2, "xn"),
+	MX25_CQG_CHAN(3, "yn"),
+	MX25_CQG_CHAN(4, "wiper"),
+	MX25_CQG_CHAN(5, "inaux0"),
+	MX25_CQG_CHAN(6, "inaux1"),
+	MX25_CQG_CHAN(7, "inaux2"),
+};
+
+static void mx25_gcq_disable_eoq(struct mx25_gcq_priv *priv)
+{
+	regmap_update_bits(priv->regs, MX25_ADCQ_MR, MX25_ADCQ_MR_EOQ_IRQ,
+			   MX25_ADCQ_MR_EOQ_IRQ);
+}
+
+static void mx25_gcq_enable_eoq(struct mx25_gcq_priv *priv)
+{
+	regmap_update_bits(priv->regs, MX25_ADCQ_MR,
+			   MX25_ADCQ_MR_EOQ_IRQ, 0);
+}
+
+static irqreturn_t mx25_gcq_irq(int irq, void *data)
+{
+	struct mx25_gcq_priv *priv = data;
+	u32 stats;
+
+	regmap_read(priv->regs, MX25_ADCQ_SR, &stats);
+
+	if (stats & MX25_ADCQ_SR_EOQ) {
+		mx25_gcq_disable_eoq(priv);
+		complete(&priv->completed);
+	}
+
+	/* Disable conversion queue run */
+	regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_FQS, 0);
+
+	/* Acknowledge all possible irqs */
+	regmap_write(priv->regs, MX25_ADCQ_SR, MX25_ADCQ_SR_FRR |
+				 MX25_ADCQ_SR_FUR | MX25_ADCQ_SR_FOR |
+				 MX25_ADCQ_SR_EOQ | MX25_ADCQ_SR_PD);
+
+	return IRQ_HANDLED;
+}
+
+static int mx25_gcq_read_raw(struct iio_dev *indio_dev,
+		struct iio_chan_spec const *chan, int *val, int *val2,
+		long mask)
+{
+	struct mx25_gcq_priv *priv = iio_priv(indio_dev);
+	long timeout;
+	u32 data;
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		mutex_lock(&indio_dev->mlock);
+
+		/* Setup the configuration we want to use */
+		regmap_write(priv->regs, MX25_ADCQ_ITEM_7_0,
+			     MX25_ADCQ_ITEM(0, chan->channel));
+
+		mx25_gcq_enable_eoq(priv);
+
+		/* Trigger queue for one run */
+		regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_FQS,
+				   MX25_ADCQ_CR_FQS);
+
+		timeout = wait_for_completion_interruptible_timeout(
+			&priv->completed, MX25_GCQ_TIMEOUT);
+		if (timeout < 0) {
+			dev_err(&indio_dev->dev,
+					 "ADC wait for measurement failed\n");
+			ret = timeout;
+			goto out;
+		} else if (timeout == 0) {
+			dev_err(&indio_dev->dev, "ADC timed out\n");
+			ret = -ETIMEDOUT;
+			goto out;
+		}
+
+		ret = regmap_read(priv->regs, MX25_ADCQ_FIFO, &data);
+		if (ret)
+			return ret;
+
+		*val = MX25_ADCQ_FIFO_DATA(data);
+		ret = IIO_VAL_INT;
+		goto out;
+
+	case IIO_CHAN_INFO_SCALE:
+		*val = priv->channel_vref_mv[chan->channel];
+		*val2 = 12;
+		return IIO_VAL_FRACTIONAL_LOG2;
+
+	default:
+		return -EINVAL;
+	}
+out:
+	mutex_unlock(&indio_dev->mlock);
+	return ret;
+}
+
+static const struct iio_info mx25_gcq_iio_info = {
+	.read_raw = mx25_gcq_read_raw,
+};
+
+static const struct regmap_config mx25_gcq_regconfig = {
+	.max_register = 0x5c,
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+};
+
+static int mx25_gcq_setup_cfgs(struct platform_device *pdev,
+			       struct mx25_gcq_priv *priv)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct device_node *child;
+	struct device *dev = &pdev->dev;
+	int ret, i;
+
+	/* Setup all configurations registers with a default conversion
+	 * configuration for each input
+	 */
+	for (i = 0; i < MX25_NUM_CFGS; ++i)
+		regmap_write(priv->regs, MX25_ADCQ_CFG(i),
+			     MX25_ADCQ_CFG_YPLL_OFF |
+			     MX25_ADCQ_CFG_XNUR_OFF |
+			     MX25_ADCQ_CFG_XPUL_OFF |
+			     MX25_ADCQ_CFG_REFP_INT |
+			     (i << 4) |
+			     MX25_ADCQ_CFG_REFN_NGND2);
+
+	for_each_child_of_node(np, child) {
+		u32 reg;
+		u32 refp;
+		u32 adc_ref;
+
+		ret = of_property_read_u32(child, "reg", &reg);
+		if (ret) {
+			dev_err(dev, "Failed to get reg property\n");
+			return ret;
+		}
+
+		if (reg >= MX25_NUM_CFGS) {
+			dev_err(dev,
+				"reg value is greater than the number of available configuration registers\n");
+			return -EINVAL;
+		}
+
+		ret = of_property_read_u32(child, "fsl,adc-ref", &adc_ref);
+		if (ret) {
+			dev_err(dev, "Failed to get fsl,adc-ref property\n");
+			return ret;
+		}
+
+		if (adc_ref != MX25_ADC_REF_INT &&
+		    adc_ref != MX25_ADC_REF_EXT) {
+			dev_err(dev, "Invalid fsl,adc-refp property value %d\n",
+				adc_ref);
+			return -EINVAL;
+		}
+
+		switch (adc_ref) {
+		case MX25_ADC_REF_EXT:
+			if (IS_ERR_OR_NULL(priv->ext_vref)) {
+				dev_err(dev,
+					"No regulator found for the external vref\n");
+				return -EINVAL;
+			}
+			priv->channel_vref_mv[reg] =
+				regulator_get_voltage(priv->ext_vref);
+			refp = MX25_ADCQ_CFG_REFP_EXT;
+			break;
+		case MX25_ADC_REF_INT:
+			priv->channel_vref_mv[reg] = 2500;
+			refp = MX25_ADCQ_CFG_REFP_INT;
+			break;
+		default:
+			return -EINVAL;
+		}
+
+		regmap_update_bits(priv->regs, MX25_ADCQ_CFG(reg),
+				   MX25_ADCQ_CFG_REFP_MASK |
+				   MX25_ADCQ_CFG_REFN_MASK, (refp << 7) |
+				   (MX25_ADCQ_CFG_REFN_NGND << 2));
+	}
+	regmap_update_bits(priv->regs, MX25_ADCQ_CR,
+			   MX25_ADCQ_CR_FRST | MX25_ADCQ_CR_QRST,
+			   MX25_ADCQ_CR_FRST | MX25_ADCQ_CR_QRST);
+
+	regmap_write(priv->regs, MX25_ADCQ_CR,
+		     MX25_ADCQ_CR_PDMSK |
+		     MX25_ADCQ_CR_QSM_FQS);
+
+	return 0;
+}
+
+static int mx25_gcq_probe(struct platform_device *pdev)
+{
+	struct iio_dev *indio_dev;
+	struct mx25_gcq_priv *priv;
+	struct mx25_tsadc *tsadc = dev_get_drvdata(pdev->dev.parent);
+	struct device *dev = &pdev->dev;
+	struct resource *res;
+	void __iomem *mem;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*priv));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	priv = iio_priv(indio_dev);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	mem = devm_ioremap_resource(dev, res);
+	if (!mem)
+		return -ENOMEM;
+
+	priv->regs = devm_regmap_init_mmio(dev, mem, &mx25_gcq_regconfig);
+	if (IS_ERR(priv->regs)) {
+		dev_err(dev, "Failed to initialize regmap\n");
+		return PTR_ERR(priv->regs);
+	}
+
+	init_completion(&priv->completed);
+
+	/* Optional external regulator */
+	priv->ext_vref = devm_regulator_get(&pdev->dev, "vref");
+	if (!IS_ERR_OR_NULL(priv->ext_vref)) {
+		ret = regulator_enable(priv->ext_vref);
+		if (ret)
+			return ret;
+	}
+
+	ret = mx25_gcq_setup_cfgs(pdev, priv);
+	if (ret)
+		return ret;
+
+	priv->clk = tsadc->clk;
+	ret = clk_prepare_enable(priv->clk);
+	if (ret) {
+		dev_err(dev, "Failed to enable clock\n");
+		return ret;
+	}
+
+	priv->irq = platform_get_irq(pdev, 0);
+	if (priv->irq <= 0) {
+		dev_err(dev, "Failed to get IRQ\n");
+		ret = priv->irq;
+		goto err_clk_unprepare;
+	}
+
+	ret = request_irq(priv->irq, mx25_gcq_irq, 0, pdev->name, priv);
+	if (ret) {
+		dev_err(dev, "Failed requesting IRQ\n");
+		goto err_clk_unprepare;
+	}
+
+	indio_dev->dev.parent = &pdev->dev;
+	indio_dev->channels = mx25_gcq_channels;
+	indio_dev->num_channels = ARRAY_SIZE(mx25_gcq_channels);
+	indio_dev->info = &mx25_gcq_iio_info;
+
+	ret = iio_device_register(indio_dev);
+	if (ret) {
+		dev_err(dev, "Failed to register iio device\n");
+		goto err_irq_free;
+	}
+
+	platform_set_drvdata(pdev, priv);
+
+	return 0;
+
+err_irq_free:
+	free_irq(priv->irq, (void *)priv);
+err_clk_unprepare:
+	clk_disable_unprepare(priv->clk);
+	return ret;
+}
+
+static int mx25_gcq_remove(struct platform_device *pdev)
+{
+	struct mx25_gcq_priv *priv = platform_get_drvdata(pdev);
+	struct iio_dev *indio_dev = iio_priv_to_dev(pdev);
+
+	iio_device_unregister(indio_dev);
+	free_irq(priv->irq, priv);
+	clk_disable_unprepare(priv->clk);
+
+	return 0;
+}
+
+static struct of_device_id mx25_gcq_ids[] = {
+	{ .compatible = "fsl,imx25-gcq", },
+	{ /* Sentinel */ }
+};
+
+static struct platform_driver mx25_gcq_driver = {
+	.driver		= {
+		.name	= "mx25-gcq",
+		.owner	= THIS_MODULE,
+		.of_match_table = mx25_gcq_ids,
+	},
+	.probe		= mx25_gcq_probe,
+	.remove		= mx25_gcq_remove,
+};
+module_platform_driver(mx25_gcq_driver);
+
+MODULE_DESCRIPTION("ADC driver for Freescale mx25");
+MODULE_AUTHOR("Markus Pargmann <mpa@pengutronix.de>");
+MODULE_LICENSE("GPL v2");
diff --git a/include/dt-bindings/iio/adc/fsl-imx25-gcq.h b/include/dt-bindings/iio/adc/fsl-imx25-gcq.h
new file mode 100644
index 0000000..486dce7
--- /dev/null
+++ b/include/dt-bindings/iio/adc/fsl-imx25-gcq.h
@@ -0,0 +1,11 @@
+/*
+ * This header provides constants for configuring the I.MX25 ADC
+ */
+
+#ifndef _DT_BINDINGS_IIO_ADC_FS_IMX25_GCQ_H
+#define _DT_BINDINGS_IIO_ADC_FS_IMX25_GCQ_H
+
+#define MX25_ADC_REF_INT	0 /* Internal voltage reference */
+#define MX25_ADC_REF_EXT	1 /* External voltage reference */
+
+#endif
-- 
1.7.9.5

[PATCH v4 6/6] ARM: imx_v4_v5_defconfig: Add I.MX25 Touchscreen controller and ADC support.

From: Denis Carikli <hidden>
Date: 2014-06-24 14:46:35

Signed-off-by: Denis Carikli <redacted>
---
Changelog v3->v4:
- None

Changelog v2->v3:
- Added ADC support, splitting it would be overkill.
---
 arch/arm/configs/imx_v4_v5_defconfig |    4 ++++
 1 file changed, 4 insertions(+)
diff --git a/arch/arm/configs/imx_v4_v5_defconfig b/arch/arm/configs/imx_v4_v5_defconfig
index 68abce9..43dd6e9 100644
--- a/arch/arm/configs/imx_v4_v5_defconfig
+++ b/arch/arm/configs/imx_v4_v5_defconfig
@@ -97,6 +97,7 @@ CONFIG_KEYBOARD_IMX=y
 # CONFIG_INPUT_MOUSE is not set
 CONFIG_INPUT_TOUCHSCREEN=y
 CONFIG_TOUCHSCREEN_ADS7846=m
+CONFIG_TOUCHSCREEN_MX25=y
 CONFIG_TOUCHSCREEN_MC13783=y
 # CONFIG_LEGACY_PTYS is not set
 CONFIG_SERIAL_8250=m
@@ -117,6 +118,7 @@ CONFIG_HWMON=m
 CONFIG_SENSORS_MC13783_ADC=m
 CONFIG_WATCHDOG=y
 CONFIG_IMX2_WDT=y
+CONFIG_MFD_MX25_TSADC=y
 CONFIG_MFD_MC13XXX_SPI=y
 CONFIG_REGULATOR=y
 CONFIG_REGULATOR_FIXED_VOLTAGE=y
@@ -183,6 +185,8 @@ CONFIG_DMADEVICES=y
 CONFIG_IMX_SDMA=y
 CONFIG_IMX_DMA=y
 # CONFIG_IOMMU_SUPPORT is not set
+CONFIG_IIO=y
+CONFIG_FSL_MX25_ADC=y
 CONFIG_EXT2_FS=y
 CONFIG_EXT3_FS=y
 CONFIG_EXT4_FS=y
-- 
1.7.9.5
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