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>

5 files changed, 593 insertions, 4 deletions

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index dca54ccdf291..b4aa2a03e19b 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -59,6 +59,9 @@ config GENERIC_HARDIRQS_NO__DO_IRQ
 config GENERIC_IRQ_PROBE
         def_bool y
 
+config GENERIC_GPIO
+        def_bool n
+
 config GENERIC_CALIBRATE_DELAY
         bool
 
diff --git a/arch/sh/include/asm/gpio.h b/arch/sh/include/asm/gpio.h
index cf32bd2df881..9650e7c9c39e 100644
--- a/arch/sh/include/asm/gpio.h
+++ b/arch/sh/include/asm/gpio.h
@@ -1,9 +1,9 @@
 /*
  *  include/asm-sh/gpio.h
  *
- *  Copyright (C) 2007 Markus Brunner, Mark Jonas
+ * Generic GPIO API and pinmux table support for SuperH.
  *
- *  Addresses for the Pin Function Controller
+ * 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
@@ -16,4 +16,92 @@
 #include <cpu/gpio.h>
 #endif
 
+typedef unsigned short pinmux_enum_t;
+typedef unsigned char pinmux_flag_t;
+
+#define PINMUX_TYPE_NONE            0
+#define PINMUX_TYPE_FUNCTION        1
+#define PINMUX_TYPE_GPIO            2
+#define PINMUX_TYPE_OUTPUT          3
+#define PINMUX_TYPE_INPUT           4
+#define PINMUX_TYPE_INPUT_PULLUP    5
+#define PINMUX_TYPE_INPUT_PULLDOWN  6
+
+#define PINMUX_FLAG_TYPE            (0x7)
+#define PINMUX_FLAG_WANT_PULLUP     (1 << 3)
+#define PINMUX_FLAG_WANT_PULLDOWN   (1 << 4)
+
+struct pinmux_gpio {
+        pinmux_enum_t enum_id;
+        pinmux_flag_t flags;
+};
+
+#define PINMUX_GPIO(gpio, data_or_mark) [gpio] = { data_or_mark }
+#define PINMUX_DATA(data_or_mark, ids...) data_or_mark, ids, 0
+
+struct pinmux_cfg_reg {
+        unsigned long reg, reg_width, field_width;
+        unsigned long *cnt;
+        pinmux_enum_t *enum_ids;
+};
+
+#define PINMUX_CFG_REG(name, r, r_width, f_width) \
+        .reg = r, .reg_width = r_width, .field_width = f_width,         \
+        .cnt = (unsigned long [r_width / f_width]) {}, \
+        .enum_ids = (pinmux_enum_t [(r_width / f_width) * (1 << f_width)]) \
+
+struct pinmux_data_reg {
+        unsigned long reg, reg_width;
+        pinmux_enum_t *enum_ids;
+};
+
+#define PINMUX_DATA_REG(name, r, r_width) \
+        .reg = r, .reg_width = r_width, \
+        .enum_ids = (pinmux_enum_t [r_width]) \
+
+struct pinmux_range {
+        pinmux_enum_t begin;
+        pinmux_enum_t end;
+};
+
+struct pinmux_info {
+        char *name;
+        pinmux_enum_t reserved_id;
+        struct pinmux_range data;
+        struct pinmux_range input;
+        struct pinmux_range input_pd;
+        struct pinmux_range input_pu;
+        struct pinmux_range output;
+        struct pinmux_range mark;
+        struct pinmux_range function;
+
+        unsigned first_gpio, last_gpio;
+
+        struct pinmux_gpio *gpios;
+        struct pinmux_cfg_reg *cfg_regs;
+        struct pinmux_data_reg *data_regs;
+
+        pinmux_enum_t *gpio_data;
+        unsigned int gpio_data_size;
+
+        unsigned long *gpio_in_use;
+};
+
+int register_pinmux(struct pinmux_info *pip);
+
+int __gpio_request(unsigned gpio);
+static inline int gpio_request(unsigned gpio, const char *label)
+{
+        return __gpio_request(gpio);
+}
+void gpio_free(unsigned gpio);
+int gpio_direction_input(unsigned gpio);
+int gpio_direction_output(unsigned gpio, int value);
+int gpio_get_value(unsigned gpio);
+void gpio_set_value(unsigned gpio, int value);
+static inline int gpio_export(unsigned gpio, bool direction_may_change)
+{
+        return 0;
+}
+
 #endif /* __ASM_SH_GPIO_H */
diff --git a/arch/sh/kernel/Makefile_32 b/arch/sh/kernel/Makefile_32
index 8497de8afbff..7c41ac7c298c 100644
--- a/arch/sh/kernel/Makefile_32
+++ b/arch/sh/kernel/Makefile_32
@@ -5,7 +5,7 @@
 extra-y := head_32.o init_task.o vmlinux.lds
 
 obj-y   := debugtraps.o io.o io_generic.o irq.o machvec.o process_32.o \
-           ptrace_32.o setup.o signal_32.o sys_sh.o sys_sh32.o \
+           ptrace_32.o setup.o signal_32.o sys_sh.o sys_sh32.o gpio.o \
            syscalls_32.o time_32.o topology.o traps.o traps_32.o
 
 obj-y                           += cpu/ timers/
diff --git a/arch/sh/kernel/Makefile_64 b/arch/sh/kernel/Makefile_64
index e987eb2e9bb5..2a7a5e694a1f 100644
--- a/arch/sh/kernel/Makefile_64
+++ b/arch/sh/kernel/Makefile_64
@@ -1,7 +1,7 @@
 extra-y := head_64.o init_task.o vmlinux.lds
 
 obj-y   := debugtraps.o io.o io_generic.o irq.o machvec.o process_64.o \
-           ptrace_64.o setup.o signal_64.o sys_sh.o sys_sh64.o \
+           ptrace_64.o setup.o signal_64.o sys_sh.o sys_sh64.o gpio.o \
            syscalls_64.o time_64.o topology.o traps.o traps_64.o
 
 obj-y                           += cpu/ timers/
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;
+}