diff options
Diffstat (limited to 'drivers/sh/pfc/core.c')
-rw-r--r-- | drivers/sh/pfc/core.c | 572 |
1 files changed, 572 insertions, 0 deletions
diff --git a/drivers/sh/pfc/core.c b/drivers/sh/pfc/core.c new file mode 100644 index 00000000000..68169373c98 --- /dev/null +++ b/drivers/sh/pfc/core.c @@ -0,0 +1,572 @@ +/* + * SuperH Pin Function Controller support. + * + * Copyright (C) 2008 Magnus Damm + * Copyright (C) 2009 - 2012 Paul Mundt + * + * 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. + */ +#define pr_fmt(fmt) "sh_pfc " KBUILD_MODNAME ": " fmt + +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/sh_pfc.h> +#include <linux/module.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/bitops.h> +#include <linux/slab.h> +#include <linux/ioport.h> +#include <linux/pinctrl/machine.h> + +static struct sh_pfc *sh_pfc __read_mostly; + +static inline bool sh_pfc_initialized(void) +{ + return !!sh_pfc; +} + +static void pfc_iounmap(struct sh_pfc *pfc) +{ + int k; + + for (k = 0; k < pfc->num_resources; k++) + if (pfc->window[k].virt) + iounmap(pfc->window[k].virt); + + kfree(pfc->window); + pfc->window = NULL; +} + +static int pfc_ioremap(struct sh_pfc *pfc) +{ + struct resource *res; + int k; + + if (!pfc->num_resources) + return 0; + + pfc->window = kzalloc(pfc->num_resources * sizeof(*pfc->window), + GFP_NOWAIT); + if (!pfc->window) + goto err1; + + for (k = 0; k < pfc->num_resources; k++) { + res = pfc->resource + k; + WARN_ON(resource_type(res) != IORESOURCE_MEM); + pfc->window[k].phys = res->start; + pfc->window[k].size = resource_size(res); + pfc->window[k].virt = ioremap_nocache(res->start, + resource_size(res)); + if (!pfc->window[k].virt) + goto err2; + } + + return 0; + +err2: + pfc_iounmap(pfc); +err1: + return -1; +} + +static void __iomem *pfc_phys_to_virt(struct sh_pfc *pfc, + unsigned long address) +{ + struct pfc_window *window; + int k; + + /* scan through physical windows and convert address */ + for (k = 0; k < pfc->num_resources; k++) { + window = pfc->window + k; + + if (address < window->phys) + continue; + + if (address >= (window->phys + window->size)) + continue; + + return window->virt + (address - window->phys); + } + + /* no windows defined, register must be 1:1 mapped virt:phys */ + return (void __iomem *)address; +} + +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 __iomem *mapped_reg, + unsigned long reg_width) +{ + switch (reg_width) { + case 8: + return ioread8(mapped_reg); + case 16: + return ioread16(mapped_reg); + case 32: + return ioread32(mapped_reg); + } + + BUG(); + return 0; +} + +static void gpio_write_raw_reg(void __iomem *mapped_reg, + unsigned long reg_width, + unsigned long data) +{ + switch (reg_width) { + case 8: + iowrite8(data, mapped_reg); + return; + case 16: + iowrite16(data, mapped_reg); + return; + case 32: + iowrite32(data, mapped_reg); + return; + } + + BUG(); +} + +int sh_pfc_read_bit(struct pinmux_data_reg *dr, unsigned long in_pos) +{ + unsigned long pos; + + pos = dr->reg_width - (in_pos + 1); + + pr_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; +} +EXPORT_SYMBOL_GPL(sh_pfc_read_bit); + +void sh_pfc_write_bit(struct pinmux_data_reg *dr, unsigned long in_pos, + unsigned long value) +{ + unsigned long pos; + + pos = dr->reg_width - (in_pos + 1); + + pr_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); +} +EXPORT_SYMBOL_GPL(sh_pfc_write_bit); + +static void config_reg_helper(struct sh_pfc *pfc, + struct pinmux_cfg_reg *crp, + unsigned long in_pos, + void __iomem **mapped_regp, + unsigned long *maskp, + unsigned long *posp) +{ + int k; + + *mapped_regp = pfc_phys_to_virt(pfc, 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 sh_pfc *pfc, + struct pinmux_cfg_reg *crp, + unsigned long field) +{ + void __iomem *mapped_reg; + unsigned long mask, pos; + + config_reg_helper(pfc, crp, field, &mapped_reg, &mask, &pos); + + pr_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 sh_pfc *pfc, + struct pinmux_cfg_reg *crp, + unsigned long field, unsigned long value) +{ + void __iomem *mapped_reg; + unsigned long mask, pos, data; + + config_reg_helper(pfc, crp, field, &mapped_reg, &mask, &pos); + + pr_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 (pfc->unlock_reg) + gpio_write_raw_reg(pfc_phys_to_virt(pfc, pfc->unlock_reg), + 32, ~data); + + gpio_write_raw_reg(mapped_reg, crp->reg_width, data); +} + +static int setup_data_reg(struct sh_pfc *pfc, unsigned gpio) +{ + struct pinmux_gpio *gpiop = &pfc->gpios[gpio]; + struct pinmux_data_reg *data_reg; + int k, n; + + if (!enum_in_range(gpiop->enum_id, &pfc->data)) + return -1; + + k = 0; + while (1) { + data_reg = pfc->data_regs + k; + + if (!data_reg->reg_width) + break; + + data_reg->mapped_reg = pfc_phys_to_virt(pfc, 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 sh_pfc *pfc) +{ + struct pinmux_data_reg *drp; + int k; + + for (k = pfc->first_gpio; k <= pfc->last_gpio; k++) + setup_data_reg(pfc, k); + + k = 0; + while (1) { + drp = pfc->data_regs + k; + + if (!drp->reg_width) + break; + + drp->reg_shadow = gpio_read_raw_reg(drp->mapped_reg, + drp->reg_width); + k++; + } +} + +int sh_pfc_get_data_reg(struct sh_pfc *pfc, unsigned gpio, + struct pinmux_data_reg **drp, int *bitp) +{ + struct pinmux_gpio *gpiop = &pfc->gpios[gpio]; + int k, n; + + if (!enum_in_range(gpiop->enum_id, &pfc->data)) + return -1; + + k = (gpiop->flags & PINMUX_FLAG_DREG) >> PINMUX_FLAG_DREG_SHIFT; + n = (gpiop->flags & PINMUX_FLAG_DBIT) >> PINMUX_FLAG_DBIT_SHIFT; + *drp = pfc->data_regs + k; + *bitp = n; + return 0; +} +EXPORT_SYMBOL_GPL(sh_pfc_get_data_reg); + +static int get_config_reg(struct sh_pfc *pfc, 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 = pfc->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; +} + +int sh_pfc_gpio_to_enum(struct sh_pfc *pfc, unsigned gpio, int pos, + pinmux_enum_t *enum_idp) +{ + pinmux_enum_t enum_id = pfc->gpios[gpio].enum_id; + pinmux_enum_t *data = pfc->gpio_data; + int k; + + if (!enum_in_range(enum_id, &pfc->data)) { + if (!enum_in_range(enum_id, &pfc->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 < pfc->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; +} +EXPORT_SYMBOL_GPL(sh_pfc_gpio_to_enum); + +int sh_pfc_config_gpio(struct sh_pfc *pfc, 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 = &pfc->output; + break; + + case PINMUX_TYPE_INPUT: + range = &pfc->input; + break; + + case PINMUX_TYPE_INPUT_PULLUP: + range = &pfc->input_pu; + break; + + case PINMUX_TYPE_INPUT_PULLDOWN: + range = &pfc->input_pd; + break; + + default: + goto out_err; + } + + pos = 0; + enum_id = 0; + field = 0; + value = 0; + while (1) { + pos = sh_pfc_gpio_to_enum(pfc, 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, &pfc->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(pfc, enum_id, &cr, + &field, &value, &cntp) != 0) + goto out_err; + + switch (cfg_mode) { + case GPIO_CFG_DRYRUN: + if (!*cntp || + (read_config_reg(pfc, cr, field) != value)) + continue; + break; + + case GPIO_CFG_REQ: + write_config_reg(pfc, cr, field, value); + *cntp = *cntp + 1; + break; + + case GPIO_CFG_FREE: + *cntp = *cntp - 1; + break; + } + } + + return 0; + out_err: + return -1; +} +EXPORT_SYMBOL_GPL(sh_pfc_config_gpio); + +int register_sh_pfc(struct sh_pfc *pfc) +{ + int (*initroutine)(struct sh_pfc *) = NULL; + int ret; + + /* + * Ensure that the type encoding fits + */ + BUILD_BUG_ON(PINMUX_FLAG_TYPE > ((1 << PINMUX_FLAG_DBIT_SHIFT) - 1)); + + if (sh_pfc) + return -EBUSY; + + ret = pfc_ioremap(pfc); + if (unlikely(ret < 0)) + return ret; + + spin_lock_init(&pfc->lock); + + pinctrl_provide_dummies(); + setup_data_regs(pfc); + + sh_pfc = pfc; + + /* + * Initialize pinctrl bindings first + */ + initroutine = symbol_request(sh_pfc_register_pinctrl); + if (initroutine) { + ret = (*initroutine)(pfc); + symbol_put_addr(initroutine); + + if (unlikely(ret != 0)) + goto err; + } else { + pr_err("failed to initialize pinctrl bindings\n"); + goto err; + } + + /* + * Then the GPIO chip + */ + initroutine = symbol_request(sh_pfc_register_gpiochip); + if (initroutine) { + ret = (*initroutine)(pfc); + symbol_put_addr(initroutine); + + /* + * If the GPIO chip fails to come up we still leave the + * PFC state as it is, given that there are already + * extant users of it that have succeeded by this point. + */ + if (unlikely(ret != 0)) { + pr_notice("failed to init GPIO chip, ignoring...\n"); + ret = 0; + } + } + + pr_info("%s support registered\n", pfc->name); + + return 0; + +err: + pfc_iounmap(pfc); + sh_pfc = NULL; + + return ret; +} |