sh: GPIO and pinmux base code

This patch adds gpio code together with the pinmux table parser.
In the future we should optimize this and switch back to gpiolib.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 498 insertions, 0 deletions

diff --git a/arch/sh/kernel/gpio.c b/arch/sh/kernel/gpio.c
new file mode 100644
index 00000000000..bb8b812c689
--- /dev/null
+++ b/arch/sh/kernel/gpio.c
@@ -0,0 +1,498 @@
+/*
+ * Pinmuxed GPIO support for SuperH.
+ *
+ * Copyright (C) 2008 Magnus Damm
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/bitops.h>
+#include <linux/gpio.h>
+
+static struct pinmux_info *registered_gpio;
+
+static struct pinmux_info *gpio_controller(unsigned gpio)
+{
+	if (!registered_gpio)
+		return NULL;
+
+	if (gpio < registered_gpio->first_gpio)
+		return NULL;
+
+	if (gpio > registered_gpio->last_gpio)
+		return NULL;
+
+	return registered_gpio;
+}
+
+static int enum_in_range(pinmux_enum_t enum_id, struct pinmux_range *r)
+{
+	if (enum_id < r->begin)
+		return 0;
+
+	if (enum_id > r->end)
+		return 0;
+
+	return 1;
+}
+
+static int read_write_reg(unsigned long reg, unsigned long reg_width,
+			  unsigned long field_width, unsigned long in_pos,
+			  unsigned long value, int do_write)
+{
+	unsigned long data, mask, pos;
+
+	data = 0;
+	mask = (1 << field_width) - 1;
+	pos = reg_width - ((in_pos + 1) * field_width);
+
+#ifdef DEBUG
+	pr_info("%s, addr = %lx, value = %ld, pos = %ld, "
+		"r_width = %ld, f_width = %ld\n",
+		do_write ? "write" : "read", reg, value, pos,
+		reg_width, field_width);
+#endif
+
+	switch (reg_width) {
+	case 8:
+		data = ctrl_inb(reg);
+		break;
+	case 16:
+		data = ctrl_inw(reg);
+		break;
+	case 32:
+		data = ctrl_inl(reg);
+		break;
+	}
+
+	if (!do_write)
+		return (data >> pos) & mask;
+
+	data &= ~(mask << pos);
+	data |= value << pos;
+
+	switch (reg_width) {
+	case 8:
+		ctrl_outb(data, reg);
+		break;
+	case 16:
+		ctrl_outw(data, reg);
+		break;
+	case 32:
+		ctrl_outl(data, reg);
+		break;
+	}
+	return 0;
+}
+
+static int get_data_reg(struct pinmux_info *gpioc, unsigned gpio,
+			struct pinmux_data_reg **drp, int *bitp)
+{
+	pinmux_enum_t enum_id = gpioc->gpios[gpio].enum_id;
+	struct pinmux_data_reg *data_reg;
+	int k, n;
+
+	if (!enum_in_range(enum_id, &gpioc->data))
+		return -1;
+
+	k = 0;
+	while (1) {
+		data_reg = gpioc->data_regs + k;
+
+		if (!data_reg->reg_width)
+			break;
+
+		for (n = 0; n < data_reg->reg_width; n++) {
+			if (data_reg->enum_ids[n] == enum_id) {
+				*drp = data_reg;
+				*bitp = n;
+				return 0;
+
+			}
+		}
+		k++;
+	}
+
+	return -1;
+}
+
+static int get_config_reg(struct pinmux_info *gpioc, pinmux_enum_t enum_id,
+			  struct pinmux_cfg_reg **crp, int *indexp,
+			  unsigned long **cntp)
+{
+	struct pinmux_cfg_reg *config_reg;
+	unsigned long r_width, f_width;
+	int k, n;
+
+	k = 0;
+	while (1) {
+		config_reg = gpioc->cfg_regs + k;
+
+		r_width = config_reg->reg_width;
+		f_width = config_reg->field_width;
+
+		if (!r_width)
+			break;
+		for (n = 0; n < (r_width / f_width) * 1 << f_width; n++) {
+			if (config_reg->enum_ids[n] == enum_id) {
+				*crp = config_reg;
+				*indexp = n;
+				*cntp = &config_reg->cnt[n / (1 << f_width)];
+				return 0;
+			}
+		}
+		k++;
+	}
+
+	return -1;
+}
+
+static int get_gpio_enum_id(struct pinmux_info *gpioc, unsigned gpio,
+			    int pos, pinmux_enum_t *enum_idp)
+{
+	pinmux_enum_t enum_id = gpioc->gpios[gpio].enum_id;
+	pinmux_enum_t *data = gpioc->gpio_data;
+	int k;
+
+	if (!enum_in_range(enum_id, &gpioc->data)) {
+		if (!enum_in_range(enum_id, &gpioc->mark)) {
+			pr_err("non data/mark enum_id for gpio %d\n", gpio);
+			return -1;
+		}
+	}
+
+	if (pos) {
+		*enum_idp = data[pos + 1];
+		return pos + 1;
+	}
+
+	for (k = 0; k < gpioc->gpio_data_size; k++) {
+		if (data[k] == enum_id) {
+			*enum_idp = data[k + 1];
+			return k + 1;
+		}
+	}
+
+	pr_err("cannot locate data/mark enum_id for gpio %d\n", gpio);
+	return -1;
+}
+
+static int write_config_reg(struct pinmux_info *gpioc,
+			    struct pinmux_cfg_reg *crp,
+			    int index)
+{
+	unsigned long ncomb, pos, value;
+
+	ncomb = 1 << crp->field_width;
+	pos = index / ncomb;
+	value = index % ncomb;
+
+	return read_write_reg(crp->reg, crp->reg_width,
+			      crp->field_width, pos, value, 1);
+}
+
+static int check_config_reg(struct pinmux_info *gpioc,
+			    struct pinmux_cfg_reg *crp,
+			    int index)
+{
+	unsigned long ncomb, pos, value;
+
+	ncomb = 1 << crp->field_width;
+	pos = index / ncomb;
+	value = index % ncomb;
+
+	if (read_write_reg(crp->reg, crp->reg_width,
+			   crp->field_width, pos, 0, 0) == value)
+		return 0;
+
+	return -1;
+}
+
+enum { GPIO_CFG_DRYRUN, GPIO_CFG_REQ, GPIO_CFG_FREE };
+
+int pinmux_config_gpio(struct pinmux_info *gpioc, unsigned gpio,
+		       int pinmux_type, int cfg_mode)
+{
+	struct pinmux_cfg_reg *cr = NULL;
+	pinmux_enum_t enum_id;
+	struct pinmux_range *range;
+	int in_range, pos, index;
+	unsigned long *cntp;
+
+	switch (pinmux_type) {
+
+	case PINMUX_TYPE_FUNCTION:
+		range = NULL;
+		break;
+
+	case PINMUX_TYPE_OUTPUT:
+		range = &gpioc->output;
+		break;
+
+	case PINMUX_TYPE_INPUT:
+		range = &gpioc->input;
+		break;
+
+	case PINMUX_TYPE_INPUT_PULLUP:
+		range = &gpioc->input_pu;
+		break;
+
+	case PINMUX_TYPE_INPUT_PULLDOWN:
+		range = &gpioc->input_pd;
+		break;
+
+	default:
+		goto out_err;
+	}
+
+	pos = 0;
+	enum_id = 0;
+	index = 0;
+	while (1) {
+		pos = get_gpio_enum_id(gpioc, gpio, pos, &enum_id);
+		if (pos <= 0)
+			goto out_err;
+
+		if (!enum_id)
+			break;
+
+		in_range = enum_in_range(enum_id, &gpioc->function);
+		if (!in_range && range)
+			in_range = enum_in_range(enum_id, range);
+
+		if (!in_range)
+			continue;
+
+		if (get_config_reg(gpioc, enum_id, &cr, &index, &cntp) != 0)
+			goto out_err;
+
+		switch (cfg_mode) {
+		case GPIO_CFG_DRYRUN:
+			if (!*cntp || !check_config_reg(gpioc, cr, index))
+				continue;
+			break;
+
+		case GPIO_CFG_REQ:
+			if (write_config_reg(gpioc, cr, index) != 0)
+				goto out_err;
+			*cntp = *cntp + 1;
+			break;
+
+		case GPIO_CFG_FREE:
+			*cntp = *cntp - 1;
+			break;
+		}
+	}
+
+	return 0;
+ out_err:
+	return -1;
+}
+
+static DEFINE_SPINLOCK(gpio_lock);
+
+int __gpio_request(unsigned gpio)
+{
+	struct pinmux_info *gpioc = gpio_controller(gpio);
+	struct pinmux_data_reg *dummy;
+	unsigned long flags;
+	int i, ret, pinmux_type;
+
+	ret = -EINVAL;
+
+	if (!gpioc)
+		goto err_out;
+
+	spin_lock_irqsave(&gpio_lock, flags);
+
+	if ((gpioc->gpios[gpio].flags & PINMUX_FLAG_TYPE) != PINMUX_TYPE_NONE)
+		goto err_unlock;
+
+	/* setup pin function here if no data is associated with pin */
+
+	if (get_data_reg(gpioc, gpio, &dummy, &i) != 0)
+		pinmux_type = PINMUX_TYPE_FUNCTION;
+	else
+		pinmux_type = PINMUX_TYPE_GPIO;
+
+	if (pinmux_type == PINMUX_TYPE_FUNCTION) {
+		if (pinmux_config_gpio(gpioc, gpio,
+				       pinmux_type,
+				       GPIO_CFG_DRYRUN) != 0)
+			goto err_unlock;
+
+		if (pinmux_config_gpio(gpioc, gpio,
+				       pinmux_type,
+				       GPIO_CFG_REQ) != 0)
+			BUG();
+	}
+
+	gpioc->gpios[gpio].flags = pinmux_type;
+
+	ret = 0;
+ err_unlock:
+	spin_unlock_irqrestore(&gpio_lock, flags);
+ err_out:
+	return ret;
+}
+EXPORT_SYMBOL(__gpio_request);
+
+void gpio_free(unsigned gpio)
+{
+	struct pinmux_info *gpioc = gpio_controller(gpio);
+	unsigned long flags;
+	int pinmux_type;
+
+	if (!gpioc)
+		return;
+
+	spin_lock_irqsave(&gpio_lock, flags);
+
+	pinmux_type = gpioc->gpios[gpio].flags & PINMUX_FLAG_TYPE;
+	pinmux_config_gpio(gpioc, gpio, pinmux_type, GPIO_CFG_FREE);
+	gpioc->gpios[gpio].flags = PINMUX_TYPE_NONE;
+
+	spin_unlock_irqrestore(&gpio_lock, flags);
+}
+EXPORT_SYMBOL(gpio_free);
+
+static int pinmux_direction(struct pinmux_info *gpioc,
+			    unsigned gpio, int new_pinmux_type)
+{
+	int ret, pinmux_type;
+
+	ret = -EINVAL;
+	pinmux_type = gpioc->gpios[gpio].flags & PINMUX_FLAG_TYPE;
+
+	switch (pinmux_type) {
+	case PINMUX_TYPE_GPIO:
+		break;
+	case PINMUX_TYPE_OUTPUT:
+	case PINMUX_TYPE_INPUT:
+	case PINMUX_TYPE_INPUT_PULLUP:
+	case PINMUX_TYPE_INPUT_PULLDOWN:
+		pinmux_config_gpio(gpioc, gpio, pinmux_type, GPIO_CFG_FREE);
+		break;
+	default:
+		goto err_out;
+	}
+
+	if (pinmux_config_gpio(gpioc, gpio,
+			       new_pinmux_type,
+			       GPIO_CFG_DRYRUN) != 0)
+		goto err_out;
+
+	if (pinmux_config_gpio(gpioc, gpio,
+			       new_pinmux_type,
+			       GPIO_CFG_REQ) != 0)
+		BUG();
+
+	gpioc->gpios[gpio].flags = new_pinmux_type;
+
+	ret = 0;
+ err_out:
+	return ret;
+}
+
+int gpio_direction_input(unsigned gpio)
+{
+	struct pinmux_info *gpioc = gpio_controller(gpio);
+	unsigned long flags;
+	int ret = -EINVAL;
+
+	if (!gpioc)
+		goto err_out;
+
+	spin_lock_irqsave(&gpio_lock, flags);
+	ret = pinmux_direction(gpioc, gpio, PINMUX_TYPE_INPUT);
+	spin_unlock_irqrestore(&gpio_lock, flags);
+ err_out:
+	return ret;
+}
+EXPORT_SYMBOL(gpio_direction_input);
+
+static int __gpio_get_set_value(struct pinmux_info *gpioc,
+				unsigned gpio, int value,
+				int do_write)
+{
+	struct pinmux_data_reg *dr = NULL;
+	int bit = 0;
+
+	if (get_data_reg(gpioc, gpio, &dr, &bit) != 0)
+		BUG();
+	else
+		value = read_write_reg(dr->reg, dr->reg_width,
+				       1, bit, value, do_write);
+
+	return value;
+}
+
+int gpio_direction_output(unsigned gpio, int value)
+{
+	struct pinmux_info *gpioc = gpio_controller(gpio);
+	unsigned long flags;
+	int ret = -EINVAL;
+
+	if (!gpioc)
+		goto err_out;
+
+	spin_lock_irqsave(&gpio_lock, flags);
+	__gpio_get_set_value(gpioc, gpio, value, 1);
+	ret = pinmux_direction(gpioc, gpio, PINMUX_TYPE_OUTPUT);
+	spin_unlock_irqrestore(&gpio_lock, flags);
+ err_out:
+	return ret;
+}
+EXPORT_SYMBOL(gpio_direction_output);
+
+int gpio_get_value(unsigned gpio)
+{
+	struct pinmux_info *gpioc = gpio_controller(gpio);
+	unsigned long flags;
+	int value = 0;
+
+	if (!gpioc)
+		BUG();
+	else {
+		spin_lock_irqsave(&gpio_lock, flags);
+		value = __gpio_get_set_value(gpioc, gpio, 0, 0);
+		spin_unlock_irqrestore(&gpio_lock, flags);
+	}
+
+	return value;
+}
+EXPORT_SYMBOL(gpio_get_value);
+
+void gpio_set_value(unsigned gpio, int value)
+{
+	struct pinmux_info *gpioc = gpio_controller(gpio);
+	unsigned long flags;
+
+	if (!gpioc)
+		BUG();
+	else {
+		spin_lock_irqsave(&gpio_lock, flags);
+		__gpio_get_set_value(gpioc, gpio, value, 1);
+		spin_unlock_irqrestore(&gpio_lock, flags);
+	}
+}
+EXPORT_SYMBOL(gpio_set_value);
+
+int register_pinmux(struct pinmux_info *pip)
+{
+	registered_gpio = pip;
+	pr_info("pinmux: %s handling gpio %d -> %d\n",
+		pip->name, pip->first_gpio, pip->last_gpio);
+
+	return 0;
+}