diff options
Diffstat (limited to 'kernel/drivers/pinctrl/meson/pinctrl-meson.c')
| -rw-r--r-- | kernel/drivers/pinctrl/meson/pinctrl-meson.c | 766 |
1 files changed, 766 insertions, 0 deletions
diff --git a/kernel/drivers/pinctrl/meson/pinctrl-meson.c b/kernel/drivers/pinctrl/meson/pinctrl-meson.c new file mode 100644 index 000000000..a70a5fe79 --- /dev/null +++ b/kernel/drivers/pinctrl/meson/pinctrl-meson.c @@ -0,0 +1,766 @@ +/* + * Pin controller and GPIO driver for Amlogic Meson SoCs + * + * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +/* + * The available pins are organized in banks (A,B,C,D,E,X,Y,Z,AO, + * BOOT,CARD for meson6, X,Y,DV,H,Z,AO,BOOT,CARD for meson8 and + * X,Y,DV,H,AO,BOOT,CARD,DIF for meson8b) and each bank has a + * variable number of pins. + * + * The AO bank is special because it belongs to the Always-On power + * domain which can't be powered off; the bank also uses a set of + * registers different from the other banks. + * + * For each of the two power domains (regular and always-on) there are + * 4 different register ranges that control the following properties + * of the pins: + * 1) pin muxing + * 2) pull enable/disable + * 3) pull up/down + * 4) GPIO direction, output value, input value + * + * In some cases the register ranges for pull enable and pull + * direction are the same and thus there are only 3 register ranges. + * + * Every pinmux group can be enabled by a specific bit in the first + * register range of the domain; when all groups for a given pin are + * disabled the pin acts as a GPIO. + * + * For the pull and GPIO configuration every bank uses a contiguous + * set of bits in the register sets described above; the same register + * can be shared by more banks with different offsets. + * + * In addition to this there are some registers shared between all + * banks that control the IRQ functionality. This feature is not + * supported at the moment by the driver. + */ + +#include <linux/device.h> +#include <linux/gpio.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/pinctrl/pinconf-generic.h> +#include <linux/pinctrl/pinconf.h> +#include <linux/pinctrl/pinctrl.h> +#include <linux/pinctrl/pinmux.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/seq_file.h> + +#include "../core.h" +#include "../pinctrl-utils.h" +#include "pinctrl-meson.h" + +/** + * meson_get_bank() - find the bank containing a given pin + * + * @domain: the domain containing the pin + * @pin: the pin number + * @bank: the found bank + * + * Return: 0 on success, a negative value on error + */ +static int meson_get_bank(struct meson_domain *domain, unsigned int pin, + struct meson_bank **bank) +{ + int i; + + for (i = 0; i < domain->data->num_banks; i++) { + if (pin >= domain->data->banks[i].first && + pin <= domain->data->banks[i].last) { + *bank = &domain->data->banks[i]; + return 0; + } + } + + return -EINVAL; +} + +/** + * meson_get_domain_and_bank() - find domain and bank containing a given pin + * + * @pc: Meson pin controller device + * @pin: the pin number + * @domain: the found domain + * @bank: the found bank + * + * Return: 0 on success, a negative value on error + */ +static int meson_get_domain_and_bank(struct meson_pinctrl *pc, unsigned int pin, + struct meson_domain **domain, + struct meson_bank **bank) +{ + struct meson_domain *d; + int i; + + for (i = 0; i < pc->data->num_domains; i++) { + d = &pc->domains[i]; + if (pin >= d->data->pin_base && + pin < d->data->pin_base + d->data->num_pins) { + *domain = d; + return meson_get_bank(d, pin, bank); + } + } + + return -EINVAL; +} + +/** + * meson_calc_reg_and_bit() - calculate register and bit for a pin + * + * @bank: the bank containing the pin + * @pin: the pin number + * @reg_type: the type of register needed (pull-enable, pull, etc...) + * @reg: the computed register offset + * @bit: the computed bit + */ +static void meson_calc_reg_and_bit(struct meson_bank *bank, unsigned int pin, + enum meson_reg_type reg_type, + unsigned int *reg, unsigned int *bit) +{ + struct meson_reg_desc *desc = &bank->regs[reg_type]; + + *reg = desc->reg * 4; + *bit = desc->bit + pin - bank->first; +} + +static int meson_get_groups_count(struct pinctrl_dev *pcdev) +{ + struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev); + + return pc->data->num_groups; +} + +static const char *meson_get_group_name(struct pinctrl_dev *pcdev, + unsigned selector) +{ + struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev); + + return pc->data->groups[selector].name; +} + +static int meson_get_group_pins(struct pinctrl_dev *pcdev, unsigned selector, + const unsigned **pins, unsigned *num_pins) +{ + struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev); + + *pins = pc->data->groups[selector].pins; + *num_pins = pc->data->groups[selector].num_pins; + + return 0; +} + +static void meson_pin_dbg_show(struct pinctrl_dev *pcdev, struct seq_file *s, + unsigned offset) +{ + seq_printf(s, " %s", dev_name(pcdev->dev)); +} + +static const struct pinctrl_ops meson_pctrl_ops = { + .get_groups_count = meson_get_groups_count, + .get_group_name = meson_get_group_name, + .get_group_pins = meson_get_group_pins, + .dt_node_to_map = pinconf_generic_dt_node_to_map_all, + .dt_free_map = pinctrl_utils_dt_free_map, + .pin_dbg_show = meson_pin_dbg_show, +}; + +/** + * meson_pmx_disable_other_groups() - disable other groups using a given pin + * + * @pc: meson pin controller device + * @pin: number of the pin + * @sel_group: index of the selected group, or -1 if none + * + * The function disables all pinmux groups using a pin except the + * selected one. If @sel_group is -1 all groups are disabled, leaving + * the pin in GPIO mode. + */ +static void meson_pmx_disable_other_groups(struct meson_pinctrl *pc, + unsigned int pin, int sel_group) +{ + struct meson_pmx_group *group; + struct meson_domain *domain; + int i, j; + + for (i = 0; i < pc->data->num_groups; i++) { + group = &pc->data->groups[i]; + if (group->is_gpio || i == sel_group) + continue; + + for (j = 0; j < group->num_pins; j++) { + if (group->pins[j] == pin) { + /* We have found a group using the pin */ + domain = &pc->domains[group->domain]; + regmap_update_bits(domain->reg_mux, + group->reg * 4, + BIT(group->bit), 0); + } + } + } +} + +static int meson_pmx_set_mux(struct pinctrl_dev *pcdev, unsigned func_num, + unsigned group_num) +{ + struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev); + struct meson_pmx_func *func = &pc->data->funcs[func_num]; + struct meson_pmx_group *group = &pc->data->groups[group_num]; + struct meson_domain *domain = &pc->domains[group->domain]; + int i, ret = 0; + + dev_dbg(pc->dev, "enable function %s, group %s\n", func->name, + group->name); + + /* + * Disable groups using the same pin. + * The selected group is not disabled to avoid glitches. + */ + for (i = 0; i < group->num_pins; i++) + meson_pmx_disable_other_groups(pc, group->pins[i], group_num); + + /* Function 0 (GPIO) doesn't need any additional setting */ + if (func_num) + ret = regmap_update_bits(domain->reg_mux, group->reg * 4, + BIT(group->bit), BIT(group->bit)); + + return ret; +} + +static int meson_pmx_request_gpio(struct pinctrl_dev *pcdev, + struct pinctrl_gpio_range *range, + unsigned offset) +{ + struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev); + + meson_pmx_disable_other_groups(pc, range->pin_base + offset, -1); + + return 0; +} + +static int meson_pmx_get_funcs_count(struct pinctrl_dev *pcdev) +{ + struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev); + + return pc->data->num_funcs; +} + +static const char *meson_pmx_get_func_name(struct pinctrl_dev *pcdev, + unsigned selector) +{ + struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev); + + return pc->data->funcs[selector].name; +} + +static int meson_pmx_get_groups(struct pinctrl_dev *pcdev, unsigned selector, + const char * const **groups, + unsigned * const num_groups) +{ + struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev); + + *groups = pc->data->funcs[selector].groups; + *num_groups = pc->data->funcs[selector].num_groups; + + return 0; +} + +static const struct pinmux_ops meson_pmx_ops = { + .set_mux = meson_pmx_set_mux, + .get_functions_count = meson_pmx_get_funcs_count, + .get_function_name = meson_pmx_get_func_name, + .get_function_groups = meson_pmx_get_groups, + .gpio_request_enable = meson_pmx_request_gpio, +}; + +static int meson_pinconf_set(struct pinctrl_dev *pcdev, unsigned int pin, + unsigned long *configs, unsigned num_configs) +{ + struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev); + struct meson_domain *domain; + struct meson_bank *bank; + enum pin_config_param param; + unsigned int reg, bit; + int i, ret; + u16 arg; + + ret = meson_get_domain_and_bank(pc, pin, &domain, &bank); + if (ret) + return ret; + + for (i = 0; i < num_configs; i++) { + param = pinconf_to_config_param(configs[i]); + arg = pinconf_to_config_argument(configs[i]); + + switch (param) { + case PIN_CONFIG_BIAS_DISABLE: + dev_dbg(pc->dev, "pin %u: disable bias\n", pin); + + meson_calc_reg_and_bit(bank, pin, REG_PULL, ®, &bit); + ret = regmap_update_bits(domain->reg_pull, reg, + BIT(bit), 0); + if (ret) + return ret; + break; + case PIN_CONFIG_BIAS_PULL_UP: + dev_dbg(pc->dev, "pin %u: enable pull-up\n", pin); + + meson_calc_reg_and_bit(bank, pin, REG_PULLEN, + ®, &bit); + ret = regmap_update_bits(domain->reg_pullen, reg, + BIT(bit), BIT(bit)); + if (ret) + return ret; + + meson_calc_reg_and_bit(bank, pin, REG_PULL, ®, &bit); + ret = regmap_update_bits(domain->reg_pull, reg, + BIT(bit), BIT(bit)); + if (ret) + return ret; + break; + case PIN_CONFIG_BIAS_PULL_DOWN: + dev_dbg(pc->dev, "pin %u: enable pull-down\n", pin); + + meson_calc_reg_and_bit(bank, pin, REG_PULLEN, + ®, &bit); + ret = regmap_update_bits(domain->reg_pullen, reg, + BIT(bit), BIT(bit)); + if (ret) + return ret; + + meson_calc_reg_and_bit(bank, pin, REG_PULL, ®, &bit); + ret = regmap_update_bits(domain->reg_pull, reg, + BIT(bit), 0); + if (ret) + return ret; + break; + default: + return -ENOTSUPP; + } + } + + return 0; +} + +static int meson_pinconf_get_pull(struct meson_pinctrl *pc, unsigned int pin) +{ + struct meson_domain *domain; + struct meson_bank *bank; + unsigned int reg, bit, val; + int ret, conf; + + ret = meson_get_domain_and_bank(pc, pin, &domain, &bank); + if (ret) + return ret; + + meson_calc_reg_and_bit(bank, pin, REG_PULLEN, ®, &bit); + + ret = regmap_read(domain->reg_pullen, reg, &val); + if (ret) + return ret; + + if (!(val & BIT(bit))) { + conf = PIN_CONFIG_BIAS_DISABLE; + } else { + meson_calc_reg_and_bit(bank, pin, REG_PULL, ®, &bit); + + ret = regmap_read(domain->reg_pull, reg, &val); + if (ret) + return ret; + + if (val & BIT(bit)) + conf = PIN_CONFIG_BIAS_PULL_UP; + else + conf = PIN_CONFIG_BIAS_PULL_DOWN; + } + + return conf; +} + +static int meson_pinconf_get(struct pinctrl_dev *pcdev, unsigned int pin, + unsigned long *config) +{ + struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev); + enum pin_config_param param = pinconf_to_config_param(*config); + u16 arg; + + switch (param) { + case PIN_CONFIG_BIAS_DISABLE: + case PIN_CONFIG_BIAS_PULL_DOWN: + case PIN_CONFIG_BIAS_PULL_UP: + if (meson_pinconf_get_pull(pc, pin) == param) + arg = 1; + else + return -EINVAL; + break; + default: + return -ENOTSUPP; + } + + *config = pinconf_to_config_packed(param, arg); + dev_dbg(pc->dev, "pinconf for pin %u is %lu\n", pin, *config); + + return 0; +} + +static int meson_pinconf_group_set(struct pinctrl_dev *pcdev, + unsigned int num_group, + unsigned long *configs, unsigned num_configs) +{ + struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev); + struct meson_pmx_group *group = &pc->data->groups[num_group]; + int i; + + dev_dbg(pc->dev, "set pinconf for group %s\n", group->name); + + for (i = 0; i < group->num_pins; i++) { + meson_pinconf_set(pcdev, group->pins[i], configs, + num_configs); + } + + return 0; +} + +static int meson_pinconf_group_get(struct pinctrl_dev *pcdev, + unsigned int group, unsigned long *config) +{ + return -ENOSYS; +} + +static const struct pinconf_ops meson_pinconf_ops = { + .pin_config_get = meson_pinconf_get, + .pin_config_set = meson_pinconf_set, + .pin_config_group_get = meson_pinconf_group_get, + .pin_config_group_set = meson_pinconf_group_set, + .is_generic = true, +}; + +static inline struct meson_domain *to_meson_domain(struct gpio_chip *chip) +{ + return container_of(chip, struct meson_domain, chip); +} + +static int meson_gpio_request(struct gpio_chip *chip, unsigned gpio) +{ + return pinctrl_request_gpio(chip->base + gpio); +} + +static void meson_gpio_free(struct gpio_chip *chip, unsigned gpio) +{ + struct meson_domain *domain = to_meson_domain(chip); + + pinctrl_free_gpio(domain->data->pin_base + gpio); +} + +static int meson_gpio_direction_input(struct gpio_chip *chip, unsigned gpio) +{ + struct meson_domain *domain = to_meson_domain(chip); + unsigned int reg, bit, pin; + struct meson_bank *bank; + int ret; + + pin = domain->data->pin_base + gpio; + ret = meson_get_bank(domain, pin, &bank); + if (ret) + return ret; + + meson_calc_reg_and_bit(bank, pin, REG_DIR, ®, &bit); + + return regmap_update_bits(domain->reg_gpio, reg, BIT(bit), BIT(bit)); +} + +static int meson_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, + int value) +{ + struct meson_domain *domain = to_meson_domain(chip); + unsigned int reg, bit, pin; + struct meson_bank *bank; + int ret; + + pin = domain->data->pin_base + gpio; + ret = meson_get_bank(domain, pin, &bank); + if (ret) + return ret; + + meson_calc_reg_and_bit(bank, pin, REG_DIR, ®, &bit); + ret = regmap_update_bits(domain->reg_gpio, reg, BIT(bit), 0); + if (ret) + return ret; + + meson_calc_reg_and_bit(bank, pin, REG_OUT, ®, &bit); + return regmap_update_bits(domain->reg_gpio, reg, BIT(bit), + value ? BIT(bit) : 0); +} + +static void meson_gpio_set(struct gpio_chip *chip, unsigned gpio, int value) +{ + struct meson_domain *domain = to_meson_domain(chip); + unsigned int reg, bit, pin; + struct meson_bank *bank; + int ret; + + pin = domain->data->pin_base + gpio; + ret = meson_get_bank(domain, pin, &bank); + if (ret) + return; + + meson_calc_reg_and_bit(bank, pin, REG_OUT, ®, &bit); + regmap_update_bits(domain->reg_gpio, reg, BIT(bit), + value ? BIT(bit) : 0); +} + +static int meson_gpio_get(struct gpio_chip *chip, unsigned gpio) +{ + struct meson_domain *domain = to_meson_domain(chip); + unsigned int reg, bit, val, pin; + struct meson_bank *bank; + int ret; + + pin = domain->data->pin_base + gpio; + ret = meson_get_bank(domain, pin, &bank); + if (ret) + return ret; + + meson_calc_reg_and_bit(bank, pin, REG_IN, ®, &bit); + regmap_read(domain->reg_gpio, reg, &val); + + return !!(val & BIT(bit)); +} + +static const struct of_device_id meson_pinctrl_dt_match[] = { + { + .compatible = "amlogic,meson8-pinctrl", + .data = &meson8_pinctrl_data, + }, + { + .compatible = "amlogic,meson8b-pinctrl", + .data = &meson8b_pinctrl_data, + }, + { }, +}; +MODULE_DEVICE_TABLE(of, meson_pinctrl_dt_match); + +static int meson_gpiolib_register(struct meson_pinctrl *pc) +{ + struct meson_domain *domain; + int i, ret; + + for (i = 0; i < pc->data->num_domains; i++) { + domain = &pc->domains[i]; + + domain->chip.label = domain->data->name; + domain->chip.dev = pc->dev; + domain->chip.request = meson_gpio_request; + domain->chip.free = meson_gpio_free; + domain->chip.direction_input = meson_gpio_direction_input; + domain->chip.direction_output = meson_gpio_direction_output; + domain->chip.get = meson_gpio_get; + domain->chip.set = meson_gpio_set; + domain->chip.base = domain->data->pin_base; + domain->chip.ngpio = domain->data->num_pins; + domain->chip.can_sleep = false; + domain->chip.of_node = domain->of_node; + domain->chip.of_gpio_n_cells = 2; + + ret = gpiochip_add(&domain->chip); + if (ret) { + dev_err(pc->dev, "can't add gpio chip %s\n", + domain->data->name); + goto fail; + } + + ret = gpiochip_add_pin_range(&domain->chip, dev_name(pc->dev), + 0, domain->data->pin_base, + domain->chip.ngpio); + if (ret) { + dev_err(pc->dev, "can't add pin range\n"); + goto fail; + } + } + + return 0; +fail: + for (i--; i >= 0; i--) + gpiochip_remove(&pc->domains[i].chip); + + return ret; +} + +static struct meson_domain_data *meson_get_domain_data(struct meson_pinctrl *pc, + struct device_node *np) +{ + int i; + + for (i = 0; i < pc->data->num_domains; i++) { + if (!strcmp(np->name, pc->data->domain_data[i].name)) + return &pc->data->domain_data[i]; + } + + return NULL; +} + +static struct regmap_config meson_regmap_config = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, +}; + +static struct regmap *meson_map_resource(struct meson_pinctrl *pc, + struct device_node *node, char *name) +{ + struct resource res; + void __iomem *base; + int i; + + i = of_property_match_string(node, "reg-names", name); + if (of_address_to_resource(node, i, &res)) + return ERR_PTR(-ENOENT); + + base = devm_ioremap_resource(pc->dev, &res); + if (IS_ERR(base)) + return ERR_CAST(base); + + meson_regmap_config.max_register = resource_size(&res) - 4; + meson_regmap_config.name = devm_kasprintf(pc->dev, GFP_KERNEL, + "%s-%s", node->name, + name); + if (!meson_regmap_config.name) + return ERR_PTR(-ENOMEM); + + return devm_regmap_init_mmio(pc->dev, base, &meson_regmap_config); +} + +static int meson_pinctrl_parse_dt(struct meson_pinctrl *pc, + struct device_node *node) +{ + struct device_node *np; + struct meson_domain *domain; + int i = 0, num_domains = 0; + + for_each_child_of_node(node, np) { + if (!of_find_property(np, "gpio-controller", NULL)) + continue; + num_domains++; + } + + if (num_domains != pc->data->num_domains) { + dev_err(pc->dev, "wrong number of subnodes\n"); + return -EINVAL; + } + + pc->domains = devm_kzalloc(pc->dev, num_domains * + sizeof(struct meson_domain), GFP_KERNEL); + if (!pc->domains) + return -ENOMEM; + + for_each_child_of_node(node, np) { + if (!of_find_property(np, "gpio-controller", NULL)) + continue; + + domain = &pc->domains[i]; + + domain->data = meson_get_domain_data(pc, np); + if (!domain->data) { + dev_err(pc->dev, "domain data not found for node %s\n", + np->name); + return -ENODEV; + } + + domain->of_node = np; + + domain->reg_mux = meson_map_resource(pc, np, "mux"); + if (IS_ERR(domain->reg_mux)) { + dev_err(pc->dev, "mux registers not found\n"); + return PTR_ERR(domain->reg_mux); + } + + domain->reg_pull = meson_map_resource(pc, np, "pull"); + if (IS_ERR(domain->reg_pull)) { + dev_err(pc->dev, "pull registers not found\n"); + return PTR_ERR(domain->reg_pull); + } + + domain->reg_pullen = meson_map_resource(pc, np, "pull-enable"); + /* Use pull region if pull-enable one is not present */ + if (IS_ERR(domain->reg_pullen)) + domain->reg_pullen = domain->reg_pull; + + domain->reg_gpio = meson_map_resource(pc, np, "gpio"); + if (IS_ERR(domain->reg_gpio)) { + dev_err(pc->dev, "gpio registers not found\n"); + return PTR_ERR(domain->reg_gpio); + } + + i++; + } + + return 0; +} + +static int meson_pinctrl_probe(struct platform_device *pdev) +{ + const struct of_device_id *match; + struct device *dev = &pdev->dev; + struct meson_pinctrl *pc; + int ret; + + pc = devm_kzalloc(dev, sizeof(struct meson_pinctrl), GFP_KERNEL); + if (!pc) + return -ENOMEM; + + pc->dev = dev; + match = of_match_node(meson_pinctrl_dt_match, pdev->dev.of_node); + pc->data = (struct meson_pinctrl_data *)match->data; + + ret = meson_pinctrl_parse_dt(pc, pdev->dev.of_node); + if (ret) + return ret; + + pc->desc.name = "pinctrl-meson"; + pc->desc.owner = THIS_MODULE; + pc->desc.pctlops = &meson_pctrl_ops; + pc->desc.pmxops = &meson_pmx_ops; + pc->desc.confops = &meson_pinconf_ops; + pc->desc.pins = pc->data->pins; + pc->desc.npins = pc->data->num_pins; + + pc->pcdev = pinctrl_register(&pc->desc, pc->dev, pc); + if (!pc->pcdev) { + dev_err(pc->dev, "can't register pinctrl device"); + return -EINVAL; + } + + ret = meson_gpiolib_register(pc); + if (ret) { + pinctrl_unregister(pc->pcdev); + return ret; + } + + return 0; +} + +static struct platform_driver meson_pinctrl_driver = { + .probe = meson_pinctrl_probe, + .driver = { + .name = "meson-pinctrl", + .of_match_table = meson_pinctrl_dt_match, + }, +}; +module_platform_driver(meson_pinctrl_driver); + +MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>"); +MODULE_DESCRIPTION("Amlogic Meson pinctrl driver"); +MODULE_LICENSE("GPL v2"); |