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 000000000000..bb8b812c6895
--- /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;
+}