[U-Boot] [PATCH v2 0/4] Add support for TI PCF8575 I2C GPIO expander

[U-Boot] [PATCH v2 0/4] Add support for TI PCF8575 I2C GPIO expander

[Vignesh R]

This series adds support for TI's PCF8575 I2C GPIO expander[1] based on
Linux Kernel driver for the same.  Also adds support for ethernet to use
new PCF8575 driver to select appropriate cpsw slaves on dra72.

Depends on I2C DM support [2]

Tested on DRA72 EVM.

[1]http://www.ti.com/lit/ds/symlink/pcf8575.pdf
[2]https://www.mail-archive.com/u-boot at lists.denx.de/msg218923.html

Vignesh R (4):
  gpio: Add driver for TI PCF8575 I2C GPIO expander
  ARM: dra7xx_evm: Enable support for TI PCF8575
  net: cpsw: Add support to drive gpios for ethernet to be functional
  ARM: dts: dra72-evm: Add mode-gpios entry for mac node

 arch/arm/dts/dra72-evm.dts                     |   2 +-
 doc/device-tree-bindings/gpio/gpio-pcf857x.txt |  71 +++++++++
 drivers/gpio/Kconfig                           |   7 +
 drivers/gpio/Makefile                          |   1 +
 drivers/gpio/pcf8575_gpio.c                    | 190 +++++++++++++++++++++++++
 drivers/net/cpsw.c                             |  12 ++
 include/configs/dra7xx_evm.h                   |   5 +
 7 files changed, 287 insertions(+), 1 deletion(-)
 create mode 100644 doc/device-tree-bindings/gpio/gpio-pcf857x.txt
 create mode 100644 drivers/gpio/pcf8575_gpio.c

-- 
2.9.2

[U-Boot] [PATCH v2 1/4] gpio: Add driver for TI PCF8575 I2C GPIO expander

[Vignesh R]

TI's PCF8575 is a 16-bit I2C GPIO expander.The device features a
16-bit quasi-bidirectional I/O ports. Each quasi-bidirectional I/O can
be used as an input or output without the use of a data-direction
control signal. The I/Os should be high before being used as inputs.
Read the device documentation for more details[1].

This driver is based on pcf857x driver available in Linux v4.7 kernel.
It supports basic reading and writing of gpio pins.

[1] http://www.ti.com/lit/ds/symlink/pcf8575.pdf

Signed-off-by: Vignesh R <vigneshr@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
---

v2: Drop GPL license text from driver  as SPDX tag is enough.

 doc/device-tree-bindings/gpio/gpio-pcf857x.txt |  71 +++++++++
 drivers/gpio/Kconfig                           |   7 +
 drivers/gpio/Makefile                          |   1 +
 drivers/gpio/pcf8575_gpio.c                    | 190 +++++++++++++++++++++++++
 4 files changed, 269 insertions(+)
 create mode 100644 doc/device-tree-bindings/gpio/gpio-pcf857x.txt
 create mode 100644 drivers/gpio/pcf8575_gpio.c

diff --git a/doc/device-tree-bindings/gpio/gpio-pcf857x.txt b/doc/device-tree-bindings/gpio/gpio-pcf857x.txt
new file mode 100644
index 000000000000..ada4e2973323
--- /dev/null
+++ b/doc/device-tree-bindings/gpio/gpio-pcf857x.txt
@@ -0,0 +1,71 @@
+* PCF857x-compatible I/O expanders
+
+The PCF857x-compatible chips have "quasi-bidirectional" I/O lines that can be
+driven high by a pull-up current source or driven low to ground. This combines
+the direction and output level into a single bit per line, which can't be read
+back. We can't actually know at initialization time whether a line is configured
+(a) as output and driving the signal low/high, or (b) as input and reporting a
+low/high value, without knowing the last value written since the chip came out
+of reset (if any). The only reliable solution for setting up line direction is
+thus to do it explicitly.
+
+Required Properties:
+
+  - compatible: should be one of the following.
+    - "maxim,max7328": For the Maxim MAX7378
+    - "maxim,max7329": For the Maxim MAX7329
+    - "nxp,pca8574": For the NXP PCA8574
+    - "nxp,pca8575": For the NXP PCA8575
+    - "nxp,pca9670": For the NXP PCA9670
+    - "nxp,pca9671": For the NXP PCA9671
+    - "nxp,pca9672": For the NXP PCA9672
+    - "nxp,pca9673": For the NXP PCA9673
+    - "nxp,pca9674": For the NXP PCA9674
+    - "nxp,pca9675": For the NXP PCA9675
+    - "nxp,pcf8574": For the NXP PCF8574
+    - "nxp,pcf8574a": For the NXP PCF8574A
+    - "nxp,pcf8575": For the NXP PCF8575
+    - "ti,tca9554": For the TI TCA9554
+
+  - reg: I2C slave address.
+
+  - gpio-controller: Marks the device node as a gpio controller.
+  - #gpio-cells: Should be 2. The first cell is the GPIO number and the second
+    cell specifies GPIO flags, as defined in <dt-bindings/gpio/gpio.h>. Only the
+    GPIO_ACTIVE_HIGH and GPIO_ACTIVE_LOW flags are supported.
+
+Optional Properties:
+
+  - lines-initial-states: Bitmask that specifies the initial state of each
+  line. When a bit is set to zero, the corresponding line will be initialized to
+  the input (pulled-up) state. When the  bit is set to one, the line will be
+  initialized the low-level output state. If the property is not specified
+  all lines will be initialized to the input state.
+
+  The I/O expander can detect input state changes, and thus optionally act as
+  an interrupt controller. When the expander interrupt line is connected all the
+  following properties must be set. For more information please see the
+  interrupt controller device tree bindings documentation available at
+  Documentation/devicetree/bindings/interrupt-controller/interrupts.txt.
+
+  - interrupt-controller: Identifies the node as an interrupt controller.
+  - #interrupt-cells: Number of cells to encode an interrupt source, shall be 2.
+  - interrupt-parent: phandle of the parent interrupt controller.
+  - interrupts: Interrupt specifier for the controllers interrupt.
+
+
+Please refer to gpio.txt in this directory for details of the common GPIO
+bindings used by client devices.
+
+Example: PCF8575 I/O expander node
+
+	pcf8575: gpio at 20 {
+		compatible = "nxp,pcf8575";
+		reg = <0x20>;
+		interrupt-parent = <&irqpin2>;
+		interrupts = <3 0>;
+		gpio-controller;
+		#gpio-cells = <2>;
+		interrupt-controller;
+		#interrupt-cells = <2>;
+	};
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 73b862dc0b21..1af05358ec76 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -79,6 +79,13 @@ config PM8916_GPIO
 	  Power and reset buttons are placed in "pm8916_key" bank and
           have gpio numbers 0 and 1 respectively.
 
+config PCF8575_GPIO
+	bool "PCF8575 I2C GPIO Expander driver"
+	depends on DM_GPIO && DM_I2C
+	help
+	 Support for PCF8575 I2C 16 bit GPIO expander. Most of these
+	 chips are from NXP and TI.
+
 config ROCKCHIP_GPIO
 	bool "Rockchip GPIO driver"
 	depends on DM_GPIO
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 792d19186aad..8f426c82cdca 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -57,3 +57,4 @@ obj-$(CONFIG_PIC32_GPIO)	+= pic32_gpio.o
 obj-$(CONFIG_MVEBU_GPIO)	+= mvebu_gpio.o
 obj-$(CONFIG_MSM_GPIO)		+= msm_gpio.o
 obj-$(CONFIG_PM8916_GPIO)	+= pm8916_gpio.o
+obj-$(CONFIG_PCF8575_GPIO)	+= pcf8575_gpio.o
diff --git a/drivers/gpio/pcf8575_gpio.c b/drivers/gpio/pcf8575_gpio.c
new file mode 100644
index 000000000000..94667b7a201e
--- /dev/null
+++ b/drivers/gpio/pcf8575_gpio.c
@@ -0,0 +1,190 @@
+/*
+ * PCF8575 I2C GPIO EXPANDER DRIVER
+ *
+ * Copyright (C) 2016 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * Vignesh R <vigneshr@ti.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0
+ *
+ *
+ * Driver for TI PCF-8575 16 bit I2C gpio expander. Based on
+ * gpio-pcf857x Linux Kernel(v4.7) driver.
+ *
+ * Copyright (C) 2007 David Brownell
+ *
+ */
+
+/*
+ * NOTE: The driver and devicetree bindings are borrowed from Linux
+ * Kernel, but driver does not support all PCF857x devices. It currently
+ * supports PCF8575 16Bit expander by TI and NXP.
+ *
+ * TODO:
+ * Support 8 bit PCF857x compatible expanders.
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <i2c.h>
+#include <asm-generic/gpio.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct pcf8575_chip {
+	int gpio_count;		/* No GPIOs supported by the chip */
+	unsigned int out;	/* software latch */
+	const char *bank_name;	/* Name of the expander bank */
+};
+
+/* Read/Write to 16-bit I/O expander */
+
+static int pcf8575_i2c_write_le16(struct udevice *dev, unsigned int word)
+{
+	struct dm_i2c_chip *chip = dev_get_parent_platdata(dev);
+	struct i2c_msg msg;
+	u8 buf[2] = { word & 0xff, word >> 8, };
+	int ret;
+
+	msg.addr = chip->chip_addr;
+	msg.buf = buf;
+	msg.flags = 0;
+	msg.len = 2;
+	ret = dm_i2c_xfer(dev, &msg, 1);
+
+	if (ret)
+		printf("%s i2c write failed to addr %x\n", __func__, msg.addr);
+
+	return ret;
+}
+
+static int pcf8575_i2c_read_le16(struct udevice *dev)
+{
+	struct dm_i2c_chip *chip = dev_get_parent_platdata(dev);
+	struct i2c_msg msg;
+	u8 buf[2];
+	int ret;
+
+	msg.addr = chip->chip_addr;
+	msg.buf = buf;
+	msg.flags = I2C_M_RD;
+	msg.len = 2;
+
+	ret = dm_i2c_xfer(dev, &msg, 1);
+	if (ret) {
+		printf("%s i2c read failed to addr %x\n", __func__, msg.addr);
+		return ret;
+	}
+
+	return (msg.buf[1] << 8) | msg.buf[0];
+}
+
+static int pcf8575_direction_input(struct udevice *dev, unsigned offset)
+{
+	struct pcf8575_chip *pc = dev_get_platdata(dev);
+	int status;
+
+	pc->out |= BIT(offset);
+	status = pcf8575_i2c_write_le16(dev, pc->out);
+
+	return status;
+}
+
+static int pcf8575_direction_output(struct udevice *dev,
+				    unsigned int offset, int value)
+{
+	struct pcf8575_chip *pc = dev_get_platdata(dev);
+	int ret;
+
+	if (value)
+		pc->out |= BIT(offset);
+	else
+		pc->out &= ~BIT(offset);
+
+	ret = pcf8575_i2c_write_le16(dev, pc->out);
+
+	return ret;
+}
+
+static int pcf8575_get_value(struct udevice *dev, unsigned int offset)
+{
+	int             value;
+
+	value = pcf8575_i2c_read_le16(dev);
+
+	return (value < 0) ? value : ((value & BIT(offset)) >> offset);
+}
+
+static int pcf8575_set_value(struct udevice *dev, unsigned int offset,
+			     int value)
+{
+	return pcf8575_direction_output(dev, offset, value);
+}
+
+static int pcf8575_ofdata_platdata(struct udevice *dev)
+{
+	struct pcf8575_chip *pc = dev_get_platdata(dev);
+	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+
+	int n_latch;
+
+	uc_priv->gpio_count = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+					     "gpio-count", 16);
+	uc_priv->bank_name = fdt_getprop(gd->fdt_blob, dev->of_offset,
+					 "gpio-bank-name", NULL);
+	if (!uc_priv->bank_name)
+		uc_priv->bank_name = fdt_get_name(gd->fdt_blob,
+						  dev->of_offset, NULL);
+
+	/* NOTE:  these chips have strange "quasi-bidirectional" I/O pins.
+	 * We can't actually know whether a pin is configured (a) as output
+	 * and driving the signal low, or (b) as input and reporting a low
+	 * value ... without knowing the last value written since the chip
+	 * came out of reset (if any).  We can't read the latched output.
+	 * In short, the only reliable solution for setting up pin direction
+	 * is to do it explicitly.
+	 *
+	 * Using n_latch avoids that trouble.  When left initialized to zero,
+	 * our software copy of the "latch" then matches the chip's all-ones
+	 * reset state.  Otherwise it flags pins to be driven low.
+	 */
+
+	n_latch = fdtdec_get_uint(gd->fdt_blob, dev->of_offset,
+				  "lines-initial-states", 0);
+	pc->out = ~n_latch;
+
+	return 0;
+}
+
+static int pcf8575_gpio_probe(struct udevice  *dev)
+{
+	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+
+	debug("%s GPIO controller with %d gpios probed\n",
+	      uc_priv->bank_name, uc_priv->gpio_count);
+
+	return 0;
+}
+
+static const struct dm_gpio_ops pcf8575_gpio_ops = {
+	.direction_input	= pcf8575_direction_input,
+	.direction_output	= pcf8575_direction_output,
+	.get_value		= pcf8575_get_value,
+	.set_value		= pcf8575_set_value,
+};
+
+static const struct udevice_id pcf8575_gpio_ids[] = {
+	{ .compatible = "nxp,pcf8575" },
+	{ .compatible = "ti,pcf8575" },
+	{ }
+};
+
+U_BOOT_DRIVER(gpio_pcf8575) = {
+	.name	= "gpio_pcf8575",
+	.id	= UCLASS_GPIO,
+	.ops	= &pcf8575_gpio_ops,
+	.of_match = pcf8575_gpio_ids,
+	.ofdata_to_platdata = pcf8575_ofdata_platdata,
+	.probe	= pcf8575_gpio_probe,
+	.platdata_auto_alloc_size = sizeof(struct pcf8575_chip),
+};
-- 
2.9.2

[U-Boot] [PATCH v2 2/4] ARM: dra7xx_evm: Enable support for TI PCF8575

[Vignesh R]

On DRA7, pcf chip present at address 0x21 on i2c1, is used to
switch between cpsw slave0 and slave1. Hence, enable PCF
driver for the same.

Signed-off-by: Vignesh R <vigneshr@ti.com>
---

v2: No change

 include/configs/dra7xx_evm.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/include/configs/dra7xx_evm.h b/include/configs/dra7xx_evm.h
index 0d51aeb86909..4ad8beaf2f75 100644
--- a/include/configs/dra7xx_evm.h
+++ b/include/configs/dra7xx_evm.h
@@ -328,4 +328,9 @@
 #define CONFIG_EEPROM_CHIP_ADDRESS 0x50
 #define CONFIG_EEPROM_BUS_ADDRESS 0
 
+/* PCF Support */
+#ifndef CONFIG_SPL_BUILD
+#define CONFIG_PCF8575_GPIO
+#endif
+
 #endif /* __CONFIG_DRA7XX_EVM_H */
-- 
2.9.2

[U-Boot] [PATCH v2 3/4] net: cpsw: Add support to drive gpios for ethernet to be functional

[Vignesh R]

On DRA72 EVM, cpsw slaves may be muxed with other modules. This
selection is controlled by a pcf gpio line. Add support for cpsw driver
to acquire mode-gpios and select the appropriate slave using gpio APIs.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
---

v2: Drop extra blank line

 drivers/net/cpsw.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/net/cpsw.c b/drivers/net/cpsw.c
index 2ce4ec69f1df..774b021e356e 100644
--- a/drivers/net/cpsw.c
+++ b/drivers/net/cpsw.c
@@ -22,6 +22,7 @@
 #include <netdev.h>
 #include <cpsw.h>
 #include <asm/errno.h>
+#include <asm/gpio.h>
 #include <asm/io.h>
 #include <phy.h>
 #include <asm/arch/cpu.h>
@@ -1152,12 +1153,14 @@ static int cpsw_eth_ofdata_to_platdata(struct udevice *dev)
 {
 	struct eth_pdata *pdata = dev_get_platdata(dev);
 	struct cpsw_priv *priv = dev_get_priv(dev);
+	struct gpio_desc *mode_gpios;
 	const char *phy_mode;
 	const void *fdt = gd->fdt_blob;
 	int node = dev->of_offset;
 	int subnode;
 	int slave_index = 0;
 	int active_slave;
+	int num_mode_gpios;
 	int ret;
 
 	pdata->iobase = dev_get_addr(dev);
@@ -1203,6 +1206,15 @@ static int cpsw_eth_ofdata_to_platdata(struct udevice *dev)
 		return -ENOENT;
 	}
 
+	num_mode_gpios = gpio_get_list_count(dev, "mode-gpios");
+	if (num_mode_gpios > 0) {
+		mode_gpios = malloc(sizeof(struct gpio_desc) *
+				    num_mode_gpios);
+		gpio_request_list_by_name(dev, "mode-gpios", mode_gpios,
+					  num_mode_gpios, GPIOD_IS_OUT);
+		free(mode_gpios);
+	}
+
 	active_slave = fdtdec_get_int(fdt, node, "active_slave", 0);
 	priv->data.active_slave = active_slave;
 
-- 
2.9.2

[U-Boot] [PATCH v2 4/4] ARM: dts: dra72-evm: Add mode-gpios entry for mac node

[Vignesh R]

On DRA72 EVM, cpsw slave1 is muxed with VIN2A, hence switch to cpsw
slave0 for ethernet. This is controlled by pcf gpio line. Add
appropriate mode-gpios DT entry so that driver can select the required
slave.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
---

v2: no change

 arch/arm/dts/dra72-evm.dts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/dts/dra72-evm.dts b/arch/arm/dts/dra72-evm.dts
index ced2f1166d8c..aee570520aa6 100644
--- a/arch/arm/dts/dra72-evm.dts
+++ b/arch/arm/dts/dra72-evm.dts
@@ -576,6 +576,7 @@
 	pinctrl-names = "default", "sleep";
 	pinctrl-0 = <&cpsw_default>;
 	pinctrl-1 = <&cpsw_sleep>;
+	mode-gpios = <&pcf_gpio_21 4 GPIO_ACTIVE_HIGH>;
 };
 
 &cpsw_emac1 {
@@ -587,7 +588,6 @@
 	pinctrl-names = "default", "sleep";
 	pinctrl-0 = <&davinci_mdio_default>;
 	pinctrl-1 = <&davinci_mdio_sleep>;
-	active_slave = <1>;
 };
 
 &dcan1 {
-- 
2.9.2

[U-Boot] [PATCH v2 2/4] ARM: dra7xx_evm: Enable support for TI PCF8575

[Tom Rini]

On Fri, Jul 29, 2016 at 04:50:23PM +0530, Vignesh R wrote:

> On DRA7, pcf chip present at address 0x21 on i2c1, is used to
> switch between cpsw slave0 and slave1. Hence, enable PCF
> driver for the same.
> 
> Signed-off-by: Vignesh R <vigneshr@ti.com>

Reviewed-by: Tom Rini <trini@konsulko.com>

-- 
Tom
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[U-Boot] [PATCH v2 3/4] net: cpsw: Add support to drive gpios for ethernet to be functional

[Joe Hershberger]

On Fri, Jul 29, 2016 at 6:20 AM, Vignesh R <vigneshr@ti.com> wrote:
> On DRA72 EVM, cpsw slaves may be muxed with other modules. This
> selection is controlled by a pcf gpio line. Add support for cpsw driver
> to acquire mode-gpios and select the appropriate slave using gpio APIs.
>
> Signed-off-by: Vignesh R <vigneshr@ti.com>
> Reviewed-by: Tom Rini <trini@konsulko.com>

Acked-by: Joe Hershberger <joe.hershberger@ni.com>

[U-Boot] [PATCH v2 0/4] Add support for TI PCF8575 I2C GPIO expander

[Vignesh R]

On Friday 29 July 2016 04:50 PM, Vignesh R wrote:
> This series adds support for TI's PCF8575 I2C GPIO expander[1] based on
> Linux Kernel driver for the same.  Also adds support for ethernet to use
> new PCF8575 driver to select appropriate cpsw slaves on dra72.
> 
> Depends on I2C DM support [2]
> 
> Tested on DRA72 EVM.
> 
> [1]http://www.ti.com/lit/ds/symlink/pcf8575.pdf
> [2]https://www.mail-archive.com/u-boot at lists.denx.de/msg218923.html

I have posted v3 of this series after addressing the additional comments
that I got for older version.

> 
> Vignesh R (4):
>   gpio: Add driver for TI PCF8575 I2C GPIO expander
>   ARM: dra7xx_evm: Enable support for TI PCF8575
>   net: cpsw: Add support to drive gpios for ethernet to be functional
>   ARM: dts: dra72-evm: Add mode-gpios entry for mac node
> 
>  arch/arm/dts/dra72-evm.dts                     |   2 +-
>  doc/device-tree-bindings/gpio/gpio-pcf857x.txt |  71 +++++++++
>  drivers/gpio/Kconfig                           |   7 +
>  drivers/gpio/Makefile                          |   1 +
>  drivers/gpio/pcf8575_gpio.c                    | 190 +++++++++++++++++++++++++
>  drivers/net/cpsw.c                             |  12 ++
>  include/configs/dra7xx_evm.h                   |   5 +
>  7 files changed, 287 insertions(+), 1 deletion(-)
>  create mode 100644 doc/device-tree-bindings/gpio/gpio-pcf857x.txt
>  create mode 100644 drivers/gpio/pcf8575_gpio.c
> 

-- 
Regards
Vignesh