diff options
Diffstat (limited to 'drivers/pinctrl/bcm/pinctrl-brcmstb.c')
| -rw-r--r-- | drivers/pinctrl/bcm/pinctrl-brcmstb.c | 442 |
1 files changed, 442 insertions, 0 deletions
diff --git a/drivers/pinctrl/bcm/pinctrl-brcmstb.c b/drivers/pinctrl/bcm/pinctrl-brcmstb.c new file mode 100644 index 000000000000..f46b27155c3c --- /dev/null +++ b/drivers/pinctrl/bcm/pinctrl-brcmstb.c @@ -0,0 +1,442 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Driver for Broadcom brcmstb GPIO units (pinctrl only) + * + * Copyright (C) 2024-2025 Ivan T. Ivanov, Andrea della Porta + * Copyright (C) 2021-3 Raspberry Pi Ltd. + * Copyright (C) 2012 Chris Boot, Simon Arlott, Stephen Warren + * + * Based heavily on the BCM2835 GPIO & pinctrl driver, which was inspired by: + * pinctrl-nomadik.c, please see original file for copyright information + * pinctrl-tegra.c, please see original file for copyright information + */ + +#include <linux/device.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/pinctrl/pinconf.h> +#include <linux/pinctrl/pinctrl.h> +#include <linux/pinctrl/pinmux.h> +#include <linux/pinctrl/pinconf-generic.h> +#include <linux/seq_file.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/cleanup.h> + +#include "pinctrl-brcmstb.h" + +#define BRCMSTB_PULL_NONE 0 +#define BRCMSTB_PULL_DOWN 1 +#define BRCMSTB_PULL_UP 2 +#define BRCMSTB_PULL_MASK 0x3 + +#define BIT_TO_REG(b) (((b) >> 5) << 2) +#define BIT_TO_SHIFT(b) ((b) & 0x1f) + +struct brcmstb_pinctrl { + struct device *dev; + void __iomem *base; + struct pinctrl_dev *pctl_dev; + struct pinctrl_desc pctl_desc; + const struct pin_regs *pin_regs; + const struct brcmstb_pin_funcs *pin_funcs; + const char * const *func_names; + unsigned int func_count; + unsigned int func_gpio; + const char *const *gpio_groups; + struct pinctrl_gpio_range gpio_range; + /* Protect FSEL registers */ + spinlock_t fsel_lock; +}; + +static unsigned int brcmstb_pinctrl_fsel_get(struct brcmstb_pinctrl *pc, + unsigned int pin) +{ + u32 bit = pc->pin_regs[pin].mux_bit; + unsigned int func; + int fsel; + u32 val; + + if (!bit) + return pc->func_gpio; + + bit &= ~MUX_BIT_VALID; + + val = readl(pc->base + BIT_TO_REG(bit)); + fsel = (val >> BIT_TO_SHIFT(bit)) & pc->pin_funcs[pin].func_mask; + func = pc->pin_funcs[pin].funcs[fsel]; + + if (func >= pc->func_count) + func = fsel; + + dev_dbg(pc->dev, "get %04x: %08x (%u => %s)\n", + BIT_TO_REG(bit), val, pin, + pc->func_names[func]); + + return func; +} + +static int brcmstb_pinctrl_fsel_set(struct brcmstb_pinctrl *pc, + unsigned int pin, unsigned int func) +{ + u32 bit = pc->pin_regs[pin].mux_bit, val, fsel_mask; + const u8 *pin_funcs; + int fsel; + int cur; + int i; + + if (!bit || func >= pc->func_count) + return -EINVAL; + + bit &= ~MUX_BIT_VALID; + + fsel = pc->pin_funcs[pin].n_funcs + 1; + fsel_mask = pc->pin_funcs[pin].func_mask; + + if (func >= fsel) { + /* Convert to an fsel number */ + pin_funcs = pc->pin_funcs[pin].funcs; + for (i = 1; i < fsel; i++) { + if (pin_funcs[i - 1] == func) { + fsel = i; + break; + } + } + } else { + fsel = func; + } + + if (fsel >= pc->pin_funcs[pin].n_funcs + 1) + return -EINVAL; + + guard(spinlock_irqsave)(&pc->fsel_lock); + + val = readl(pc->base + BIT_TO_REG(bit)); + cur = (val >> BIT_TO_SHIFT(bit)) & fsel_mask; + + dev_dbg(pc->dev, "read %04x: %08x (%u => %s)\n", + BIT_TO_REG(bit), val, pin, + pc->func_names[cur]); + + if (cur != fsel) { + val &= ~(fsel_mask << BIT_TO_SHIFT(bit)); + val |= fsel << BIT_TO_SHIFT(bit); + + dev_dbg(pc->dev, "write %04x: %08x (%u <= %s)\n", + BIT_TO_REG(bit), val, pin, + pc->func_names[fsel]); + writel(val, pc->base + BIT_TO_REG(bit)); + } + + return 0; +} + +static int brcmstb_pctl_get_groups_count(struct pinctrl_dev *pctldev) +{ + struct brcmstb_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + + return pc->pctl_desc.npins; +} + +static const char *brcmstb_pctl_get_group_name(struct pinctrl_dev *pctldev, + unsigned int selector) +{ + struct brcmstb_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + + return pc->gpio_groups[selector]; +} + +static int brcmstb_pctl_get_group_pins(struct pinctrl_dev *pctldev, + unsigned int selector, + const unsigned int **pins, + unsigned int *num_pins) +{ + struct brcmstb_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + + *pins = &pc->pctl_desc.pins[selector].number; + *num_pins = 1; + + return 0; +} + +static void brcmstb_pctl_pin_dbg_show(struct pinctrl_dev *pctldev, + struct seq_file *s, unsigned int offset) +{ + struct brcmstb_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + unsigned int fsel = brcmstb_pinctrl_fsel_get(pc, offset); + const char *fname = pc->func_names[fsel]; + + seq_printf(s, "function %s", fname); +} + +static void brcmstb_pctl_dt_free_map(struct pinctrl_dev *pctldev, + struct pinctrl_map *maps, + unsigned int num_maps) +{ + int i; + + for (i = 0; i < num_maps; i++) + if (maps[i].type == PIN_MAP_TYPE_CONFIGS_PIN) + kfree(maps[i].data.configs.configs); + + kfree(maps); +} + +static const struct pinctrl_ops brcmstb_pctl_ops = { + .get_groups_count = brcmstb_pctl_get_groups_count, + .get_group_name = brcmstb_pctl_get_group_name, + .get_group_pins = brcmstb_pctl_get_group_pins, + .pin_dbg_show = brcmstb_pctl_pin_dbg_show, + .dt_node_to_map = pinconf_generic_dt_node_to_map_all, + .dt_free_map = brcmstb_pctl_dt_free_map, +}; + +static int brcmstb_pmx_free(struct pinctrl_dev *pctldev, unsigned int offset) +{ + struct brcmstb_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + + /* disable by setting to GPIO */ + return brcmstb_pinctrl_fsel_set(pc, offset, pc->func_gpio); +} + +static int brcmstb_pmx_get_functions_count(struct pinctrl_dev *pctldev) +{ + struct brcmstb_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + + return pc->func_count; +} + +static const char *brcmstb_pmx_get_function_name(struct pinctrl_dev *pctldev, + unsigned int selector) +{ + struct brcmstb_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + + return (selector < pc->func_count) ? pc->func_names[selector] : NULL; +} + +static int brcmstb_pmx_get_function_groups(struct pinctrl_dev *pctldev, + unsigned int selector, + const char *const **groups, + unsigned *const num_groups) +{ + struct brcmstb_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + + *groups = pc->gpio_groups; + *num_groups = pc->pctl_desc.npins; + + return 0; +} + +static int brcmstb_pmx_set(struct pinctrl_dev *pctldev, + unsigned int func_selector, + unsigned int group_selector) +{ + struct brcmstb_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + const struct pinctrl_desc *pctldesc = &pc->pctl_desc; + const struct pinctrl_pin_desc *pindesc; + + if (group_selector >= pctldesc->npins) + return -EINVAL; + + pindesc = &pctldesc->pins[group_selector]; + return brcmstb_pinctrl_fsel_set(pc, pindesc->number, func_selector); +} + +static int brcmstb_pmx_gpio_request_enable(struct pinctrl_dev *pctldev, + struct pinctrl_gpio_range *range, + unsigned int pin) +{ + struct brcmstb_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + + return brcmstb_pinctrl_fsel_set(pc, pin, pc->func_gpio); +} + +static void brcmstb_pmx_gpio_disable_free(struct pinctrl_dev *pctldev, + struct pinctrl_gpio_range *range, + unsigned int offset) +{ + struct brcmstb_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + + /* disable by setting to GPIO */ + (void)brcmstb_pinctrl_fsel_set(pc, offset, pc->func_gpio); +} + +static bool brcmstb_pmx_function_is_gpio(struct pinctrl_dev *pctldev, + unsigned int selector) +{ + struct brcmstb_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + + return pc->func_gpio == selector; +} + +static const struct pinmux_ops brcmstb_pmx_ops = { + .free = brcmstb_pmx_free, + .get_functions_count = brcmstb_pmx_get_functions_count, + .get_function_name = brcmstb_pmx_get_function_name, + .get_function_groups = brcmstb_pmx_get_function_groups, + .set_mux = brcmstb_pmx_set, + .gpio_request_enable = brcmstb_pmx_gpio_request_enable, + .gpio_disable_free = brcmstb_pmx_gpio_disable_free, + .function_is_gpio = brcmstb_pmx_function_is_gpio, + .strict = true, +}; + +static unsigned int brcmstb_pull_config_get(struct brcmstb_pinctrl *pc, + unsigned int pin) +{ + u32 bit = pc->pin_regs[pin].pad_bit, val; + + if (bit == PAD_BIT_INVALID) + return BRCMSTB_PULL_NONE; + + val = readl(pc->base + BIT_TO_REG(bit)); + return (val >> BIT_TO_SHIFT(bit)) & BRCMSTB_PULL_MASK; +} + +static int brcmstb_pull_config_set(struct brcmstb_pinctrl *pc, + unsigned int pin, unsigned int arg) +{ + u32 bit = pc->pin_regs[pin].pad_bit, val; + + if (bit == PAD_BIT_INVALID) { + dev_warn(pc->dev, "Can't set pulls for %s\n", + pc->gpio_groups[pin]); + return -EINVAL; + } + + guard(spinlock_irqsave)(&pc->fsel_lock); + + val = readl(pc->base + BIT_TO_REG(bit)); + val &= ~(BRCMSTB_PULL_MASK << BIT_TO_SHIFT(bit)); + val |= (arg << BIT_TO_SHIFT(bit)); + writel(val, pc->base + BIT_TO_REG(bit)); + + return 0; +} + +static int brcmstb_pinconf_get(struct pinctrl_dev *pctldev, unsigned int pin, + unsigned long *config) +{ + struct brcmstb_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + enum pin_config_param param = pinconf_to_config_param(*config); + u32 arg; + + switch (param) { + case PIN_CONFIG_BIAS_DISABLE: + arg = (brcmstb_pull_config_get(pc, pin) == BRCMSTB_PULL_NONE); + break; + case PIN_CONFIG_BIAS_PULL_DOWN: + arg = (brcmstb_pull_config_get(pc, pin) == BRCMSTB_PULL_DOWN); + break; + case PIN_CONFIG_BIAS_PULL_UP: + arg = (brcmstb_pull_config_get(pc, pin) == BRCMSTB_PULL_UP); + break; + default: + return -ENOTSUPP; + } + + *config = pinconf_to_config_packed(param, arg); + + return 0; +} + +static int brcmstb_pinconf_set(struct pinctrl_dev *pctldev, + unsigned int pin, unsigned long *configs, + unsigned int num_configs) +{ + struct brcmstb_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev); + int ret = 0; + u32 param; + int i; + + for (i = 0; i < num_configs; i++) { + param = pinconf_to_config_param(configs[i]); + + switch (param) { + case PIN_CONFIG_BIAS_DISABLE: + ret = brcmstb_pull_config_set(pc, pin, BRCMSTB_PULL_NONE); + break; + case PIN_CONFIG_BIAS_PULL_DOWN: + ret = brcmstb_pull_config_set(pc, pin, BRCMSTB_PULL_DOWN); + break; + case PIN_CONFIG_BIAS_PULL_UP: + ret = brcmstb_pull_config_set(pc, pin, BRCMSTB_PULL_UP); + break; + default: + return -ENOTSUPP; + } + } + + return ret; +} + +static const struct pinconf_ops brcmstb_pinconf_ops = { + .is_generic = true, + .pin_config_get = brcmstb_pinconf_get, + .pin_config_set = brcmstb_pinconf_set, +}; + +int brcmstb_pinctrl_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + const struct brcmstb_pdata *pdata; + struct brcmstb_pinctrl *pc; + const char **names; + int num_pins, i; + + pdata = of_device_get_match_data(dev); + + pc = devm_kzalloc(dev, sizeof(*pc), GFP_KERNEL); + if (!pc) + return -ENOMEM; + + platform_set_drvdata(pdev, pc); + pc->dev = dev; + spin_lock_init(&pc->fsel_lock); + + pc->base = devm_of_iomap(dev, np, 0, NULL); + if (IS_ERR(pc->base)) + return dev_err_probe(&pdev->dev, PTR_ERR(pc->base), + "Could not get IO memory\n"); + + pc->pctl_desc = *pdata->pctl_desc; + pc->pctl_desc.pctlops = &brcmstb_pctl_ops; + pc->pctl_desc.pmxops = &brcmstb_pmx_ops; + pc->pctl_desc.confops = &brcmstb_pinconf_ops; + pc->pctl_desc.owner = THIS_MODULE; + num_pins = pc->pctl_desc.npins; + names = devm_kmalloc_array(dev, num_pins, sizeof(const char *), + GFP_KERNEL); + if (!names) + return -ENOMEM; + + for (i = 0; i < num_pins; i++) + names[i] = pc->pctl_desc.pins[i].name; + + pc->gpio_groups = names; + pc->pin_regs = pdata->pin_regs; + pc->pin_funcs = pdata->pin_funcs; + pc->func_count = pdata->func_count; + pc->func_names = pdata->func_names; + + pc->pctl_dev = devm_pinctrl_register(dev, &pc->pctl_desc, pc); + if (IS_ERR(pc->pctl_dev)) + return dev_err_probe(&pdev->dev, PTR_ERR(pc->pctl_dev), + "Failed to register pinctrl device\n"); + + pc->gpio_range = *pdata->gpio_range; + pinctrl_add_gpio_range(pc->pctl_dev, &pc->gpio_range); + + return 0; +} +EXPORT_SYMBOL(brcmstb_pinctrl_probe); + +MODULE_AUTHOR("Phil Elwell"); +MODULE_AUTHOR("Jonathan Bell"); +MODULE_AUTHOR("Ivan T. Ivanov"); +MODULE_AUTHOR("Andrea della Porta"); +MODULE_DESCRIPTION("Broadcom brcmstb pinctrl driver"); +MODULE_LICENSE("GPL"); |