sh: Add support pin function control using GPIO

Renesas SH and R-Mobile set up device using PFC.
This provide the framework. Most codes were brought from linux kernel.

Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>

2 files changed, 630 insertions, 0 deletions

diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 32a2474..106549d 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -40,6 +40,7 @@ COBJS-$(CONFIG_TEGRA_GPIO)	+= tegra_gpio.o
 COBJS-$(CONFIG_DA8XX_GPIO)	+= da8xx_gpio.o
 COBJS-$(CONFIG_ALTERA_PIO)	+= altera_pio.o
 COBJS-$(CONFIG_MPC83XX_GPIO)	+= mpc83xx_gpio.o
+COBJS-$(CONFIG_SH_GPIO_PFC)	+= sh_pfc.o
 
 COBJS	:= $(COBJS-y)
 SRCS 	:= $(COBJS:.o=.c)
diff --git a/drivers/gpio/sh_pfc.c b/drivers/gpio/sh_pfc.c
new file mode 100644
index 0000000..7a5af20
--- /dev/null
+++ b/drivers/gpio/sh_pfc.c
@@ -0,0 +1,629 @@
+/*
+ * Pinmuxed GPIO support for SuperH.
+ * Copy from linux kernel driver/sh/pfc.c
+ *
+ * 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 <common.h>
+#include <asm/bitops.h>
+#include <asm/io.h>
+#include <sh_pfc.h>
+
+static struct pinmux_info *gpioc;
+
+#define pfc_phys_to_virt(p, a) ((void *)a)
+
+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 unsigned long gpio_read_raw_reg(void *mapped_reg,
+				       unsigned long reg_width)
+{
+	switch (reg_width) {
+
+	case 8:
+		return readb(mapped_reg);
+	case 16:
+		return readw(mapped_reg);
+	case 32:
+		return readl(mapped_reg);
+	}
+
+	BUG();
+	return 0;
+}
+
+static void gpio_write_raw_reg(void *mapped_reg,
+			       unsigned long reg_width,
+			       unsigned long data)
+{
+	switch (reg_width) {
+	case 8:
+		writeb(data, mapped_reg);
+		return;
+	case 16:
+		writew(data, mapped_reg);
+		return;
+	case 32:
+		writel(data, mapped_reg);
+		return;
+	}
+
+	BUG();
+}
+
+static int gpio_read_bit(struct pinmux_data_reg *dr,
+			 unsigned long in_pos)
+{
+	unsigned long pos;
+
+	pos = dr->reg_width - (in_pos + 1);
+
+	debug("read_bit: addr = %lx, pos = %ld, "
+		 "r_width = %ld\n", dr->reg, pos, dr->reg_width);
+
+	return (gpio_read_raw_reg(dr->mapped_reg, dr->reg_width) >> pos) & 1;
+}
+
+static void gpio_write_bit(struct pinmux_data_reg *dr,
+			   unsigned long in_pos, unsigned long value)
+{
+	unsigned long pos;
+
+	pos = dr->reg_width - (in_pos + 1);
+
+	debug("write_bit addr = %lx, value = %d, pos = %ld, "
+		 "r_width = %ld\n",
+		 dr->reg, !!value, pos, dr->reg_width);
+
+	if (value)
+		__set_bit(pos, &dr->reg_shadow);
+	else
+		__clear_bit(pos, &dr->reg_shadow);
+
+	gpio_write_raw_reg(dr->mapped_reg, dr->reg_width, dr->reg_shadow);
+}
+
+static void config_reg_helper(struct pinmux_info *gpioc,
+			      struct pinmux_cfg_reg *crp,
+			      unsigned long in_pos,
+#if 0
+			      void __iomem **mapped_regp,
+#else
+			      void **mapped_regp,
+#endif
+			      unsigned long *maskp,
+			      unsigned long *posp)
+{
+	int k;
+
+	*mapped_regp = pfc_phys_to_virt(gpioc, crp->reg);
+
+	if (crp->field_width) {
+		*maskp = (1 << crp->field_width) - 1;
+		*posp = crp->reg_width - ((in_pos + 1) * crp->field_width);
+	} else {
+		*maskp = (1 << crp->var_field_width[in_pos]) - 1;
+		*posp = crp->reg_width;
+		for (k = 0; k <= in_pos; k++)
+			*posp -= crp->var_field_width[k];
+	}
+}
+
+static int read_config_reg(struct pinmux_info *gpioc,
+			   struct pinmux_cfg_reg *crp,
+			   unsigned long field)
+{
+	void *mapped_reg;
+
+	unsigned long mask, pos;
+
+	config_reg_helper(gpioc, crp, field, &mapped_reg, &mask, &pos);
+
+	debug("read_reg: addr = %lx, field = %ld, "
+		 "r_width = %ld, f_width = %ld\n",
+		 crp->reg, field, crp->reg_width, crp->field_width);
+
+	return (gpio_read_raw_reg(mapped_reg, crp->reg_width) >> pos) & mask;
+}
+
+static void write_config_reg(struct pinmux_info *gpioc,
+			     struct pinmux_cfg_reg *crp,
+			     unsigned long field, unsigned long value)
+{
+	void *mapped_reg;
+	unsigned long mask, pos, data;
+
+	config_reg_helper(gpioc, crp, field, &mapped_reg, &mask, &pos);
+
+	debug("write_reg addr = %lx, value = %ld, field = %ld, "
+		 "r_width = %ld, f_width = %ld\n",
+		 crp->reg, value, field, crp->reg_width, crp->field_width);
+
+	mask = ~(mask << pos);
+	value = value << pos;
+
+	data = gpio_read_raw_reg(mapped_reg, crp->reg_width);
+	data &= mask;
+	data |= value;
+
+	if (gpioc->unlock_reg)
+		gpio_write_raw_reg(pfc_phys_to_virt(gpioc, gpioc->unlock_reg),
+				   32, ~data);
+
+	gpio_write_raw_reg(mapped_reg, crp->reg_width, data);
+}
+
+static int setup_data_reg(struct pinmux_info *gpioc, unsigned gpio)
+{
+	struct pinmux_gpio *gpiop = &gpioc->gpios[gpio];
+	struct pinmux_data_reg *data_reg;
+	int k, n;
+
+	if (!enum_in_range(gpiop->enum_id, &gpioc->data))
+		return -1;
+
+	k = 0;
+	while (1) {
+		data_reg = gpioc->data_regs + k;
+
+		if (!data_reg->reg_width)
+			break;
+
+		data_reg->mapped_reg = pfc_phys_to_virt(gpioc, data_reg->reg);
+
+		for (n = 0; n < data_reg->reg_width; n++) {
+			if (data_reg->enum_ids[n] == gpiop->enum_id) {
+				gpiop->flags &= ~PINMUX_FLAG_DREG;
+				gpiop->flags |= (k << PINMUX_FLAG_DREG_SHIFT);
+				gpiop->flags &= ~PINMUX_FLAG_DBIT;
+				gpiop->flags |= (n << PINMUX_FLAG_DBIT_SHIFT);
+				return 0;
+			}
+		}
+		k++;
+	}
+
+	BUG();
+
+	return -1;
+}
+
+static void setup_data_regs(struct pinmux_info *gpioc)
+{
+	struct pinmux_data_reg *drp;
+	int k;
+
+	for (k = gpioc->first_gpio; k <= gpioc->last_gpio; k++)
+		setup_data_reg(gpioc, k);
+
+	k = 0;
+	while (1) {
+		drp = gpioc->data_regs + k;
+
+		if (!drp->reg_width)
+			break;
+
+		drp->reg_shadow = gpio_read_raw_reg(drp->mapped_reg,
+						    drp->reg_width);
+		k++;
+	}
+}
+
+static int get_data_reg(struct pinmux_info *gpioc, unsigned gpio,
+			struct pinmux_data_reg **drp, int *bitp)
+{
+	struct pinmux_gpio *gpiop = &gpioc->gpios[gpio];
+	int k, n;
+
+	if (!enum_in_range(gpiop->enum_id, &gpioc->data))
+		return -1;
+
+	k = (gpiop->flags & PINMUX_FLAG_DREG) >> PINMUX_FLAG_DREG_SHIFT;
+	n = (gpiop->flags & PINMUX_FLAG_DBIT) >> PINMUX_FLAG_DBIT_SHIFT;
+	*drp = gpioc->data_regs + k;
+	*bitp = n;
+	return 0;
+}
+
+static int get_config_reg(struct pinmux_info *gpioc, pinmux_enum_t enum_id,
+			  struct pinmux_cfg_reg **crp,
+			  int *fieldp, int *valuep,
+			  unsigned long **cntp)
+{
+	struct pinmux_cfg_reg *config_reg;
+	unsigned long r_width, f_width, curr_width, ncomb;
+	int k, m, n, pos, bit_pos;
+
+	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;
+
+		pos = 0;
+		m = 0;
+		for (bit_pos = 0; bit_pos < r_width; bit_pos += curr_width) {
+			if (f_width)
+				curr_width = f_width;
+			else
+				curr_width = config_reg->var_field_width[m];
+
+			ncomb = 1 << curr_width;
+			for (n = 0; n < ncomb; n++) {
+				if (config_reg->enum_ids[pos + n] == enum_id) {
+					*crp = config_reg;
+					*fieldp = m;
+					*valuep = n;
+					*cntp = &config_reg->cnt[m];
+					return 0;
+				}
+			}
+			pos += ncomb;
+			m++;
+		}
+		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)) {
+			debug("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;
+		}
+	}
+
+	debug("cannot locate data/mark enum_id for gpio %d\n", gpio);
+	return -1;
+}
+
+enum { GPIO_CFG_DRYRUN, GPIO_CFG_REQ, GPIO_CFG_FREE };
+
+static 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, field, value;
+	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;
+	field = 0;
+	value = 0;
+	while (1) {
+		pos = get_gpio_enum_id(gpioc, gpio, pos, &enum_id);
+		if (pos <= 0)
+			goto out_err;
+
+		if (!enum_id)
+			break;
+
+		/* first check if this is a function enum */
+		in_range = enum_in_range(enum_id, &gpioc->function);
+		if (!in_range) {
+			/* not a function enum */
+			if (range) {
+				/*
+				 * other range exists, so this pin is
+				 * a regular GPIO pin that now is being
+				 * bound to a specific direction.
+				 *
+				 * for this case we only allow function enums
+				 * and the enums that match the other range.
+				 */
+				in_range = enum_in_range(enum_id, range);
+
+				/*
+				 * special case pass through for fixed
+				 * input-only or output-only pins without
+				 * function enum register association.
+				 */
+				if (in_range && enum_id == range->force)
+					continue;
+			} else {
+				/*
+				 * no other range exists, so this pin
+				 * must then be of the function type.
+				 *
+				 * allow function type pins to select
+				 * any combination of function/in/out
+				 * in their MARK lists.
+				 */
+				in_range = 1;
+			}
+		}
+
+		if (!in_range)
+			continue;
+
+		if (get_config_reg(gpioc, enum_id, &cr,
+				   &field, &value, &cntp) != 0)
+			goto out_err;
+
+		switch (cfg_mode) {
+		case GPIO_CFG_DRYRUN:
+			if (!*cntp ||
+			    (read_config_reg(gpioc, cr, field) != value))
+				continue;
+			break;
+
+		case GPIO_CFG_REQ:
+			write_config_reg(gpioc, cr, field, value);
+			*cntp = *cntp + 1;
+			break;
+
+		case GPIO_CFG_FREE:
+			*cntp = *cntp - 1;
+			break;
+		}
+	}
+
+	return 0;
+ out_err:
+	return -1;
+}
+
+#if 0
+static DEFINE_SPINLOCK(gpio_lock);
+static struct pinmux_info *chip_to_pinmux(struct gpio_chip *chip)
+{
+	return container_of(chip, struct pinmux_info, chip);
+}
+#endif
+
+static int sh_gpio_request(unsigned offset)
+{
+	struct pinmux_data_reg *dummy;
+	int i, ret, pinmux_type;
+
+	ret = -1;
+
+	if (!gpioc)
+		goto err_out;
+
+	if ((gpioc->gpios[offset].flags & PINMUX_FLAG_TYPE) != PINMUX_TYPE_NONE)
+		goto err_out;
+
+	/* setup pin function here if no data is associated with pin */
+
+	if (get_data_reg(gpioc, offset, &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, offset,
+				       pinmux_type,
+				       GPIO_CFG_DRYRUN) != 0)
+			goto err_out;
+
+		if (pinmux_config_gpio(gpioc, offset,
+				       pinmux_type,
+				       GPIO_CFG_REQ) != 0)
+			BUG();
+	}
+
+	gpioc->gpios[offset].flags &= ~PINMUX_FLAG_TYPE;
+	gpioc->gpios[offset].flags |= pinmux_type;
+
+	ret = 0;
+err_out:
+	return ret;
+}
+
+static void sh_gpio_free(unsigned offset)
+{
+	int pinmux_type;
+
+	if (!gpioc)
+		return;
+
+	pinmux_type = gpioc->gpios[offset].flags & PINMUX_FLAG_TYPE;
+	pinmux_config_gpio(gpioc, offset, pinmux_type, GPIO_CFG_FREE);
+	gpioc->gpios[offset].flags &= ~PINMUX_FLAG_TYPE;
+	gpioc->gpios[offset].flags |= PINMUX_TYPE_NONE;
+}
+
+static int pinmux_direction(struct pinmux_info *gpioc,
+			    unsigned gpio, int new_pinmux_type)
+{
+	int pinmux_type;
+	int ret = -1;
+
+	if (!gpioc)
+		goto err_out;
+
+	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 &= ~PINMUX_FLAG_TYPE;
+	gpioc->gpios[gpio].flags |= new_pinmux_type;
+
+	ret = 0;
+ err_out:
+	return ret;
+}
+
+static int sh_gpio_direction_input(unsigned offset)
+{
+	return pinmux_direction(gpioc, offset, PINMUX_TYPE_INPUT);
+}
+
+static void sh_gpio_set_value(struct pinmux_info *gpioc,
+			     unsigned gpio, int value)
+{
+	struct pinmux_data_reg *dr = NULL;
+	int bit = 0;
+
+	if (!gpioc || get_data_reg(gpioc, gpio, &dr, &bit) != 0)
+		BUG();
+	else
+		gpio_write_bit(dr, bit, value);
+}
+
+static int sh_gpio_direction_output(unsigned offset, int value)
+{
+	sh_gpio_set_value(gpioc, offset, value);
+	return pinmux_direction(gpioc, offset, PINMUX_TYPE_OUTPUT);
+}
+
+static int sh_gpio_get_value(struct pinmux_info *gpioc, unsigned gpio)
+{
+	struct pinmux_data_reg *dr = NULL;
+	int bit = 0;
+
+	if (!gpioc || get_data_reg(gpioc, gpio, &dr, &bit) != 0)
+		return -1;
+
+	return gpio_read_bit(dr, bit);
+}
+
+static int sh_gpio_get(unsigned offset)
+{
+	return sh_gpio_get_value(gpioc, offset);
+}
+
+static void sh_gpio_set(unsigned offset, int value)
+{
+	sh_gpio_set_value(gpioc, offset, value);
+}
+
+int register_pinmux(struct pinmux_info *pip)
+{
+	if (pip != NULL) {
+		gpioc = pip;
+		debug("%s deregistering\n", pip->name);
+		setup_data_regs(gpioc);
+	}
+	return 0;
+}
+
+int unregister_pinmux(struct pinmux_info *pip)
+{
+	debug("%s deregistering\n", pip->name);
+	if (gpioc != pip)
+		return -1;
+
+	gpioc = NULL;
+	return 0;
+}
+
+int gpio_request(unsigned gpio, const char *label)
+{
+	sh_gpio_request(gpio);
+	return 0;
+}
+
+int gpio_free(unsigned gpio)
+{
+	sh_gpio_free(gpio);
+	return 0;
+}
+
+int gpio_direction_input(unsigned gpio)
+{
+	return sh_gpio_direction_input(gpio);
+}
+
+int gpio_direction_output(unsigned gpio, int value)
+{
+	return sh_gpio_direction_output(gpio, value);
+}
+
+void gpio_set_value(unsigned gpio, int value)
+{
+	sh_gpio_set(gpio, value);
+}
+
+int gpio_get_value(unsigned gpio)
+{
+	return sh_gpio_get(gpio);
+}