gpio: xilinx: Convert driver to DM

This patch is enabling GPIO_DM support to have an option to use this
driver together with zynq gpio driver.
!DM part is kept there till Microblaze is cleanup which will be done
hopefully soon.

Just a note:
There is no reason to initialize uc-priv->name because it is completely
unused.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>

drivers/gpio/xilinx_gpio.c

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * Copyright (c) 2013 Xilinx, Michal Simek
+ * Copyright (c) 2013 - 2018 Xilinx, Michal Simek
  */
 
 #include <common.h>
@@ -9,6 +9,7 @@
 #include <linux/list.h>
 #include <asm/io.h>
 #include <asm/gpio.h>
+#include <dm.h>
 
 static LIST_HEAD(gpio_list);
 
@@ -23,6 +24,8 @@ struct gpio_regs {
 	u32 gpiodir;
 };
 
+#if !defined(CONFIG_DM_GPIO)
+
 #define GPIO_NAME_SIZE	10
 
 struct gpio_names {
@@ -345,3 +348,263 @@ int gpio_alloc_dual(u32 baseaddr, const char *name, u32 gpio_no0, u32 gpio_no1)
 	/* Return the first gpio allocated for this device */
 	return ret;
 }
+#else
+#include <dt-bindings/gpio/gpio.h>
+
+#define XILINX_GPIO_MAX_BANK	2
+
+struct xilinx_gpio_platdata {
+	struct gpio_regs *regs;
+	int bank_max[XILINX_GPIO_MAX_BANK];
+	int bank_input[XILINX_GPIO_MAX_BANK];
+	int bank_output[XILINX_GPIO_MAX_BANK];
+};
+
+static int xilinx_gpio_get_bank_pin(unsigned offset, u32 *bank_num,
+				    u32 *bank_pin_num, struct udevice *dev)
+{
+	struct xilinx_gpio_platdata *platdata = dev_get_platdata(dev);
+	u32 bank, max_pins;
+	/* the first gpio is 0 not 1 */
+	u32 pin_num = offset;
+
+	for (bank = 0; bank < XILINX_GPIO_MAX_BANK; bank++) {
+		max_pins = platdata->bank_max[bank];
+		if (pin_num < max_pins) {
+			debug("%s: found at bank 0x%x pin 0x%x\n", __func__,
+			      bank, pin_num);
+			*bank_num = bank;
+			*bank_pin_num = pin_num;
+			return 0;
+		}
+		pin_num -= max_pins;
+	}
+
+	return -EINVAL;
+}
+
+static int xilinx_gpio_set_value(struct udevice *dev, unsigned offset,
+				 int value)
+{
+	struct xilinx_gpio_platdata *platdata = dev_get_platdata(dev);
+	int val, ret;
+	u32 bank, pin;
+
+	ret = xilinx_gpio_get_bank_pin(offset, &bank, &pin, dev);
+	if (ret)
+		return ret;
+
+	debug("%s: regs: %lx, value: %x, gpio: %x, bank %x, pin %x\n",
+	      __func__, (ulong)platdata->regs, value, offset, bank, pin);
+
+	if (value) {
+		val = readl(&platdata->regs->gpiodata + bank * 2);
+		val = val | (1 << pin);
+		writel(val, &platdata->regs->gpiodata + bank * 2);
+	} else {
+		val = readl(&platdata->regs->gpiodata + bank * 2);
+		val = val & ~(1 << pin);
+		writel(val, &platdata->regs->gpiodata + bank * 2);
+	}
+
+	return val;
+};
+
+static int xilinx_gpio_get_value(struct udevice *dev, unsigned offset)
+{
+	struct xilinx_gpio_platdata *platdata = dev_get_platdata(dev);
+	int val, ret;
+	u32 bank, pin;
+
+	ret = xilinx_gpio_get_bank_pin(offset, &bank, &pin, dev);
+	if (ret)
+		return ret;
+
+	debug("%s: regs: %lx, gpio: %x, bank %x, pin %x\n", __func__,
+	      (ulong)platdata->regs, offset, bank, pin);
+
+	val = readl(&platdata->regs->gpiodata + bank * 2);
+	val = !!(val & (1 << pin));
+
+	return val;
+};
+
+static int xilinx_gpio_get_function(struct udevice *dev, unsigned offset)
+{
+	struct xilinx_gpio_platdata *platdata = dev_get_platdata(dev);
+	int val, ret;
+	u32 bank, pin;
+
+	/* Check if all pins are inputs */
+	if (platdata->bank_input[bank])
+		return GPIOF_INPUT;
+
+	/* Check if all pins are outputs */
+	if (platdata->bank_output[bank])
+		return GPIOF_OUTPUT;
+
+	ret = xilinx_gpio_get_bank_pin(offset, &bank, &pin, dev);
+	if (ret)
+		return ret;
+
+	/* FIXME test on dual */
+	val = readl(&platdata->regs->gpiodir + bank * 2);
+	val = !(val & (1 << pin));
+
+	/* input is 1 in reg but GPIOF_INPUT is 0 */
+	/* output is 0 in reg but GPIOF_OUTPUT is 1 */
+
+	return val;
+}
+
+static int xilinx_gpio_direction_output(struct udevice *dev, unsigned offset,
+					int value)
+{
+	struct xilinx_gpio_platdata *platdata = dev_get_platdata(dev);
+	int val, ret;
+	u32 bank, pin;
+
+	ret = xilinx_gpio_get_bank_pin(offset, &bank, &pin, dev);
+	if (ret)
+		return ret;
+
+	/* can't change it if all is input by default */
+	if (platdata->bank_input[bank])
+		return -EINVAL;
+
+	if (!platdata->bank_output[bank]) {
+		val = readl(&platdata->regs->gpiodir + bank * 2);
+		val = val & ~(1 << pin);
+		writel(val, &platdata->regs->gpiodir + bank * 2);
+	}
+
+	xilinx_gpio_set_value(dev, offset, value);
+
+	return 0;
+}
+
+static int xilinx_gpio_direction_input(struct udevice *dev, unsigned offset)
+{
+	struct xilinx_gpio_platdata *platdata = dev_get_platdata(dev);
+	int val, ret;
+	u32 bank, pin;
+
+	ret = xilinx_gpio_get_bank_pin(offset, &bank, &pin, dev);
+	if (ret)
+		return ret;
+
+	/* Already input */
+	if (platdata->bank_input[bank])
+		return 0;
+
+	/* can't change it if all is output by default */
+	if (platdata->bank_output[bank])
+		return -EINVAL;
+
+	val = readl(&platdata->regs->gpiodir + bank * 2);
+	val = val | (1 << pin);
+	writel(val, &platdata->regs->gpiodir + bank * 2);
+
+	return 0;
+}
+
+static int xilinx_gpio_xlate(struct udevice *dev, struct gpio_desc *desc,
+			     struct ofnode_phandle_args *args)
+{
+	struct xilinx_gpio_platdata *platdata = dev_get_platdata(dev);
+
+	desc->offset = args->args[0];
+
+	debug("%s: argc: %x, [0]: %x, [1]: %x, [2]: %x\n", __func__,
+	      args->args_count, args->args[0], args->args[1], args->args[2]);
+
+	/*
+	 * The second cell is channel offset:
+	 *  0 is first channel, 8 is second channel
+	 *
+	 * U-Boot driver just combine channels together that's why simply
+	 * add amount of pins in second channel if present.
+	 */
+	if (args->args[1]) {
+		if (!platdata->bank_max[1]) {
+			printf("%s: %s has no second channel\n",
+			       __func__, dev->name);
+			return -EINVAL;
+		}
+
+		desc->offset += platdata->bank_max[0];
+	}
+
+	/* The third cell is optional */
+	if (args->args_count > 2)
+		desc->flags = (args->args[2] &
+			       GPIO_ACTIVE_LOW ? GPIOD_ACTIVE_LOW : 0);
+
+	debug("%s: offset %x, flags %lx\n",
+	      __func__, desc->offset, desc->flags);
+	return 0;
+}
+
+static const struct dm_gpio_ops xilinx_gpio_ops = {
+	.direction_input = xilinx_gpio_direction_input,
+	.direction_output = xilinx_gpio_direction_output,
+	.get_value = xilinx_gpio_get_value,
+	.set_value = xilinx_gpio_set_value,
+	.get_function = xilinx_gpio_get_function,
+	.xlate = xilinx_gpio_xlate,
+};
+
+static int xilinx_gpio_probe(struct udevice *dev)
+{
+	struct xilinx_gpio_platdata *platdata = dev_get_platdata(dev);
+	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+
+	uc_priv->bank_name = dev->name;
+
+	uc_priv->gpio_count = platdata->bank_max[0] + platdata->bank_max[1];
+
+	return 0;
+}
+
+static int xilinx_gpio_ofdata_to_platdata(struct udevice *dev)
+{
+	struct xilinx_gpio_platdata *platdata = dev_get_platdata(dev);
+	int is_dual;
+
+	platdata->regs = (struct gpio_regs *)dev_read_addr(dev);
+
+	platdata->bank_max[0] = dev_read_u32_default(dev,
+						     "xlnx,gpio-width", 0);
+	platdata->bank_input[0] = dev_read_u32_default(dev,
+						       "xlnx,all-inputs", 0);
+	platdata->bank_output[0] = dev_read_u32_default(dev,
+							"xlnx,all-outputs", 0);
+
+	is_dual = dev_read_u32_default(dev, "xlnx,is-dual", 0);
+	if (is_dual) {
+		platdata->bank_max[1] = dev_read_u32_default(dev,
+						"xlnx,gpio2-width", 0);
+		platdata->bank_input[1] = dev_read_u32_default(dev,
+						"xlnx,all-inputs-2", 0);
+		platdata->bank_output[1] = dev_read_u32_default(dev,
+						"xlnx,all-outputs-2", 0);
+	}
+
+	return 0;
+}
+
+static const struct udevice_id xilinx_gpio_ids[] = {
+	{ .compatible = "xlnx,xps-gpio-1.00.a",},
+	{ }
+};
+
+U_BOOT_DRIVER(xilinx_gpio) = {
+	.name = "xlnx_gpio",
+	.id = UCLASS_GPIO,
+	.ops = &xilinx_gpio_ops,
+	.of_match = xilinx_gpio_ids,
+	.ofdata_to_platdata = xilinx_gpio_ofdata_to_platdata,
+	.probe = xilinx_gpio_probe,
+	.platdata_auto_alloc_size = sizeof(struct xilinx_gpio_platdata),
+};
+#endif