dm: gpio: pca953x: introduce driver model support for pca953x

Introduce a new driver that supports driver model for pca953x.
The pca953x chips are used as I2C I/O expanders.
This driver is designed to support the following chips:
"
4 bits: pca9536, pca9537
8 bits: max7310, max7315, pca6107, pca9534, pca9538, pca9554,
        pca9556, pca9557, pca9574, tca6408, xra1202
16 bits: max7312, max7313, pca9535, pca9539, pca9555, pca9575,
         tca6416
24 bits: tca6424
40 bits: pca9505, pca9698
"
But for now this driver only supports max 24 bits and pca953x compatible
chips. pca957x compatible chips are not supported now.
These can be addressed when we need to add such support for the different
chips.
This driver has been tested on i.MX6 SoloX Sabreauto board with max7310
i2c expander using gpio command as following:

=>gpio status -a
Bank gpio@30_:
gpio@30_0: input: 1 [ ]

=> dm tree:
 i2c         [   ]    |   |   `-- i2c@021a8000
 gpio        [   ]    |   |       |-- gpio@30
 gpio        [   ]    |   |       `-- gpio@32

Signed-off-by: Peng Fan <van.freenix@gmail.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Wenyou Yang <wenyou.yang@atmel.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: Purna Chandra Mandal <purna.mandal@microchip.com>
Cc: Thomas Chou <thomas@wytron.com.tw>
Cc: Bhuvanchandra DV <bhuvanchandra.dv@toradex.com>
Cc: Andrea Scian <andrea.scian@dave.eu>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Michal Simek <michal.simek@xilinx.com> #on ZynqMP zcu102

3 files changed, 375 insertions, 0 deletions

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 2b4624d..e6337c2 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -143,4 +143,26 @@ config ZYNQ_GPIO
 	help
 	  Supports GPIO access on Zynq SoC.
 
+config DM_PCA953X
+	bool "PCA95[357]x, PCA9698, TCA64xx, and MAX7310 I/O ports"
+	depends on DM_GPIO
+	help
+	  Say yes here to provide access to several register-oriented
+	  SMBus I/O expanders, made mostly by NXP or TI.  Compatible
+	  models include:
+
+	  4 bits:	pca9536, pca9537
+
+	  8 bits:	max7310, max7315, pca6107, pca9534, pca9538, pca9554,
+			pca9556, pca9557, pca9574, tca6408, xra1202
+
+	  16 bits:	max7312, max7313, pca9535, pca9539, pca9555, pca9575,
+			tca6416
+
+	  24 bits:	tca6424
+
+	  40 bits:	pca9505, pca9698
+
+	  Now, max 24 bits chips and PCA953X compatible chips are
+	  supported
 endmenu
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 4f071c4..4b1f6b9 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -11,6 +11,8 @@ obj-$(CONFIG_AXP_GPIO)		+= axp_gpio.o
 endif
 obj-$(CONFIG_DM_GPIO)		+= gpio-uclass.o
 
+obj-$(CONFIG_DM_PCA953X)	+= pca953x_gpio.o
+
 obj-$(CONFIG_AT91_GPIO)	+= at91_gpio.o
 obj-$(CONFIG_ATMEL_PIO4)	+= atmel_pio4.o
 obj-$(CONFIG_INTEL_ICH6_GPIO)	+= intel_ich6_gpio.o
diff --git a/drivers/gpio/pca953x_gpio.c b/drivers/gpio/pca953x_gpio.c
new file mode 100644
index 0000000..987d10e
--- /dev/null
+++ b/drivers/gpio/pca953x_gpio.c
@@ -0,0 +1,351 @@
+/*
+ * Take linux kernel driver drivers/gpio/gpio-pca953x.c for reference.
+ *
+ * Copyright (C) 2016 Peng Fan <van.freenix@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ *
+ */
+
+/*
+ * Note:
+ * The driver's compatible table is borrowed from Linux Kernel,
+ * but now max supported gpio pins is 24 and only PCA953X_TYPE
+ * is supported. PCA957X_TYPE is not supported now.
+ * Also the Polarity Inversion feature is not supported now.
+ *
+ * TODO:
+ * 1. Support PCA957X_TYPE
+ * 2. Support max 40 gpio pins
+ * 3. Support Plolarity Inversion
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <dm.h>
+#include <fdtdec.h>
+#include <i2c.h>
+#include <malloc.h>
+#include <asm/gpio.h>
+#include <asm/io.h>
+#include <dt-bindings/gpio/gpio.h>
+
+#define PCA953X_INPUT           0
+#define PCA953X_OUTPUT          1
+#define PCA953X_INVERT          2
+#define PCA953X_DIRECTION       3
+
+#define PCA_GPIO_MASK           0x00FF
+#define PCA_INT                 0x0100
+#define PCA953X_TYPE            0x1000
+#define PCA957X_TYPE            0x2000
+#define PCA_TYPE_MASK           0xF000
+#define PCA_CHIP_TYPE(x)        ((x) & PCA_TYPE_MASK)
+
+enum {
+	PCA953X_DIRECTION_IN,
+	PCA953X_DIRECTION_OUT,
+};
+
+#define MAX_BANK 3
+#define BANK_SZ 8
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/*
+ * struct pca953x_info - Data for pca953x
+ *
+ * @dev: udevice structure for the device
+ * @addr: i2c slave address
+ * @invert: Polarity inversion or not
+ * @gpio_count: the number of gpio pins that the device supports
+ * @chip_type: indicate the chip type,PCA953X or PCA957X
+ * @bank_count: the number of banks that the device supports
+ * @reg_output: array to hold the value of output registers
+ * @reg_direction: array to hold the value of direction registers
+ */
+struct pca953x_info {
+	struct udevice *dev;
+	int addr;
+	int invert;
+	int gpio_count;
+	int chip_type;
+	int bank_count;
+	u8 reg_output[MAX_BANK];
+	u8 reg_direction[MAX_BANK];
+};
+
+static int pca953x_write_single(struct udevice *dev, int reg, u8 val,
+				int offset)
+{
+	struct pca953x_info *info = dev_get_platdata(dev);
+	int bank_shift = fls((info->gpio_count - 1) / BANK_SZ);
+	int off = offset / BANK_SZ;
+	int ret = 0;
+
+	ret = dm_i2c_write(dev, (reg << bank_shift) + off, &val, 1);
+	if (ret) {
+		dev_err(dev, "%s error\n", __func__);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int pca953x_read_single(struct udevice *dev, int reg, u8 *val,
+			       int offset)
+{
+	struct pca953x_info *info = dev_get_platdata(dev);
+	int bank_shift = fls((info->gpio_count - 1) / BANK_SZ);
+	int off = offset / BANK_SZ;
+	int ret;
+	u8 byte;
+
+	ret = dm_i2c_read(dev, (reg << bank_shift) + off, &byte, 1);
+	if (ret) {
+		dev_err(dev, "%s error\n", __func__);
+		return ret;
+	}
+
+	*val = byte;
+
+	return 0;
+}
+
+static int pca953x_read_regs(struct udevice *dev, int reg, u8 *val)
+{
+	struct pca953x_info *info = dev_get_platdata(dev);
+	int ret = 0;
+
+	if (info->gpio_count <= 8) {
+		ret = dm_i2c_read(dev, reg, val, 1);
+	} else if (info->gpio_count <= 16) {
+		ret = dm_i2c_read(dev, reg << 1, val, info->bank_count);
+	} else {
+		dev_err(dev, "Unsupported now\n");
+		return -EINVAL;
+	}
+
+	return ret;
+}
+
+static int pca953x_is_output(struct udevice *dev, int offset)
+{
+	struct pca953x_info *info = dev_get_platdata(dev);
+
+	int bank = offset / BANK_SZ;
+	int off = offset % BANK_SZ;
+
+	/*0: output; 1: input */
+	return !(info->reg_direction[bank] & (1 << off));
+}
+
+static int pca953x_get_value(struct udevice *dev, unsigned offset)
+{
+	int ret;
+	u8 val = 0;
+
+	ret = pca953x_read_single(dev, PCA953X_INPUT, &val, offset);
+	if (ret)
+		return ret;
+
+	return (val >> offset) & 0x1;
+}
+
+static int pca953x_set_value(struct udevice *dev, unsigned offset,
+			     int value)
+{
+	struct pca953x_info *info = dev_get_platdata(dev);
+	int bank = offset / BANK_SZ;
+	int off = offset % BANK_SZ;
+	u8 val;
+	int ret;
+
+	if (value)
+		val = info->reg_output[bank] | (1 << off);
+	else
+		val = info->reg_output[bank] & ~(1 << off);
+
+	ret = pca953x_write_single(dev, PCA953X_OUTPUT, val, offset);
+	if (ret)
+		return ret;
+
+	info->reg_output[bank] = val;
+
+	return 0;
+}
+
+static int pca953x_set_direction(struct udevice *dev, unsigned offset, int dir)
+{
+	struct pca953x_info *info = dev_get_platdata(dev);
+	int bank = offset / BANK_SZ;
+	int off = offset % BANK_SZ;
+	u8 val;
+	int ret;
+
+	if (dir == PCA953X_DIRECTION_IN)
+		val = info->reg_direction[bank] | (1 << off);
+	else
+		val = info->reg_direction[bank] & ~(1 << off);
+
+	ret = pca953x_write_single(dev, PCA953X_DIRECTION, val, offset);
+	if (ret)
+		return ret;
+
+	info->reg_direction[bank] = val;
+
+	return 0;
+}
+
+static int pca953x_direction_input(struct udevice *dev, unsigned offset)
+{
+	return pca953x_set_direction(dev, offset, PCA953X_DIRECTION_IN);
+}
+
+static int pca953x_direction_output(struct udevice *dev, unsigned offset,
+				    int value)
+{
+	/* Configure output value. */
+	pca953x_set_value(dev, offset, value);
+
+	/* Configure direction as output. */
+	pca953x_set_direction(dev, offset, PCA953X_DIRECTION_OUT);
+
+	return 0;
+}
+
+static int pca953x_get_function(struct udevice *dev, unsigned offset)
+{
+	if (pca953x_is_output(dev, offset))
+		return GPIOF_OUTPUT;
+	else
+		return GPIOF_INPUT;
+}
+
+static int pca953x_xlate(struct udevice *dev, struct gpio_desc *desc,
+			 struct fdtdec_phandle_args *args)
+{
+	desc->offset = args->args[0];
+	desc->flags = args->args[1] & GPIO_ACTIVE_LOW ? GPIOD_ACTIVE_LOW : 0;
+
+	return 0;
+}
+
+static const struct dm_gpio_ops pca953x_ops = {
+	.direction_input	= pca953x_direction_input,
+	.direction_output	= pca953x_direction_output,
+	.get_value		= pca953x_get_value,
+	.set_value		= pca953x_set_value,
+	.get_function		= pca953x_get_function,
+	.xlate			= pca953x_xlate,
+};
+
+static int pca953x_probe(struct udevice *dev)
+{
+	struct pca953x_info *info = dev_get_platdata(dev);
+	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+	struct dm_i2c_chip *chip = dev_get_parent_platdata(dev);
+	char name[32], *str;
+	int addr;
+	ulong driver_data;
+	int ret;
+
+	if (!info) {
+		dev_err(dev, "platdata not ready\n");
+		return -ENOMEM;
+	}
+
+	if (!chip) {
+		dev_err(dev, "i2c not ready\n");
+		return -ENODEV;
+	}
+
+	addr = fdtdec_get_int(gd->fdt_blob, dev->of_offset, "reg", 0);
+	if (addr == 0)
+		return -ENODEV;
+
+	info->addr = addr;
+
+	driver_data = dev_get_driver_data(dev);
+
+	info->gpio_count = driver_data & PCA_GPIO_MASK;
+	if (info->gpio_count > MAX_BANK * BANK_SZ) {
+		dev_err(dev, "Max support %d pins now\n", MAX_BANK * BANK_SZ);
+		return -EINVAL;
+	}
+
+	info->chip_type = PCA_CHIP_TYPE(driver_data);
+	if (info->chip_type != PCA953X_TYPE) {
+		dev_err(dev, "Only support PCA953X chip type now.\n");
+		return -EINVAL;
+	}
+
+	info->bank_count = DIV_ROUND_UP(info->gpio_count, BANK_SZ);
+
+	ret = pca953x_read_regs(dev, PCA953X_OUTPUT, info->reg_output);
+	if (ret) {
+		dev_err(dev, "Error reading output register\n");
+		return ret;
+	}
+
+	ret = pca953x_read_regs(dev, PCA953X_DIRECTION, info->reg_direction);
+	if (ret) {
+		dev_err(dev, "Error reading direction register\n");
+		return ret;
+	}
+
+	snprintf(name, sizeof(name), "gpio@%x_", info->addr);
+	str = strdup(name);
+	if (!str)
+		return -ENOMEM;
+	uc_priv->bank_name = str;
+	uc_priv->gpio_count = info->gpio_count;
+
+	dev_dbg(dev, "%s is ready\n", str);
+
+	return 0;
+}
+
+#define OF_953X(__nrgpio, __int) (ulong)(__nrgpio | PCA953X_TYPE | __int)
+#define OF_957X(__nrgpio, __int) (ulong)(__nrgpio | PCA957X_TYPE | __int)
+
+static const struct udevice_id pca953x_ids[] = {
+	{ .compatible = "nxp,pca9505", .data = OF_953X(40, PCA_INT), },
+	{ .compatible = "nxp,pca9534", .data = OF_953X(8, PCA_INT), },
+	{ .compatible = "nxp,pca9535", .data = OF_953X(16, PCA_INT), },
+	{ .compatible = "nxp,pca9536", .data = OF_953X(4, 0), },
+	{ .compatible = "nxp,pca9537", .data = OF_953X(4, PCA_INT), },
+	{ .compatible = "nxp,pca9538", .data = OF_953X(8, PCA_INT), },
+	{ .compatible = "nxp,pca9539", .data = OF_953X(16, PCA_INT), },
+	{ .compatible = "nxp,pca9554", .data = OF_953X(8, PCA_INT), },
+	{ .compatible = "nxp,pca9555", .data = OF_953X(16, PCA_INT), },
+	{ .compatible = "nxp,pca9556", .data = OF_953X(8, 0), },
+	{ .compatible = "nxp,pca9557", .data = OF_953X(8, 0), },
+	{ .compatible = "nxp,pca9574", .data = OF_957X(8, PCA_INT), },
+	{ .compatible = "nxp,pca9575", .data = OF_957X(16, PCA_INT), },
+	{ .compatible = "nxp,pca9698", .data = OF_953X(40, 0), },
+
+	{ .compatible = "maxim,max7310", .data = OF_953X(8, 0), },
+	{ .compatible = "maxim,max7312", .data = OF_953X(16, PCA_INT), },
+	{ .compatible = "maxim,max7313", .data = OF_953X(16, PCA_INT), },
+	{ .compatible = "maxim,max7315", .data = OF_953X(8, PCA_INT), },
+
+	{ .compatible = "ti,pca6107", .data = OF_953X(8, PCA_INT), },
+	{ .compatible = "ti,tca6408", .data = OF_953X(8, PCA_INT), },
+	{ .compatible = "ti,tca6416", .data = OF_953X(16, PCA_INT), },
+	{ .compatible = "ti,tca6424", .data = OF_953X(24, PCA_INT), },
+
+	{ .compatible = "onsemi,pca9654", .data = OF_953X(8, PCA_INT), },
+
+	{ .compatible = "exar,xra1202", .data = OF_953X(8, 0), },
+	{ }
+};
+
+U_BOOT_DRIVER(pca953x) = {
+	.name		= "pca953x",
+	.id		= UCLASS_GPIO,
+	.ops		= &pca953x_ops,
+	.probe		= pca953x_probe,
+	.platdata_auto_alloc_size = sizeof(struct pca953x_info),
+	.of_match	= pca953x_ids,
+};