diff options
Diffstat (limited to 'arch/sh/kernel/gpio.c')
| -rw-r--r-- | arch/sh/kernel/gpio.c | 498 |
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; +} |