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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 | // SPDX-License-Identifier: GPL-2.0 /* * GPIO library for the ACCES IDIO-16 family * Copyright (C) 2022 William Breathitt Gray */ #include <linux/bits.h> #include <linux/device.h> #include <linux/err.h> #include <linux/export.h> #include <linux/gpio/regmap.h> #include <linux/module.h> #include <linux/regmap.h> #include <linux/types.h> #include "gpio-idio-16.h" #define DEFAULT_SYMBOL_NAMESPACE GPIO_IDIO_16 #define IDIO_16_DAT_BASE 0x0 #define IDIO_16_OUT_BASE IDIO_16_DAT_BASE #define IDIO_16_IN_BASE (IDIO_16_DAT_BASE + 1) #define IDIO_16_CLEAR_INTERRUPT 0x1 #define IDIO_16_ENABLE_IRQ 0x2 #define IDIO_16_DEACTIVATE_INPUT_FILTERS 0x3 #define IDIO_16_DISABLE_IRQ IDIO_16_ENABLE_IRQ #define IDIO_16_INTERRUPT_STATUS 0x6 #define IDIO_16_NGPIO 32 #define IDIO_16_NGPIO_PER_REG 8 #define IDIO_16_REG_STRIDE 4 struct idio_16_data { struct regmap *map; unsigned int irq_mask; }; static int idio_16_handle_mask_sync(const int index, const unsigned int mask_buf_def, const unsigned int mask_buf, void *const irq_drv_data) { struct idio_16_data *const data = irq_drv_data; const unsigned int prev_mask = data->irq_mask; int err; unsigned int val; /* exit early if no change since the previous mask */ if (mask_buf == prev_mask) return 0; /* remember the current mask for the next mask sync */ data->irq_mask = mask_buf; /* if all previously masked, enable interrupts when unmasking */ if (prev_mask == mask_buf_def) { err = regmap_write(data->map, IDIO_16_CLEAR_INTERRUPT, 0x00); if (err) return err; return regmap_read(data->map, IDIO_16_ENABLE_IRQ, &val); } /* if all are currently masked, disable interrupts */ if (mask_buf == mask_buf_def) return regmap_write(data->map, IDIO_16_DISABLE_IRQ, 0x00); return 0; } static int idio_16_reg_mask_xlate(struct gpio_regmap *const gpio, const unsigned int base, const unsigned int offset, unsigned int *const reg, unsigned int *const mask) { unsigned int stride; /* Input lines start at GPIO 16 */ if (offset < 16) { stride = offset / IDIO_16_NGPIO_PER_REG; *reg = IDIO_16_OUT_BASE + stride * IDIO_16_REG_STRIDE; } else { stride = (offset - 16) / IDIO_16_NGPIO_PER_REG; *reg = IDIO_16_IN_BASE + stride * IDIO_16_REG_STRIDE; } *mask = BIT(offset % IDIO_16_NGPIO_PER_REG); return 0; } static const char *idio_16_names[IDIO_16_NGPIO] = { "OUT0", "OUT1", "OUT2", "OUT3", "OUT4", "OUT5", "OUT6", "OUT7", "OUT8", "OUT9", "OUT10", "OUT11", "OUT12", "OUT13", "OUT14", "OUT15", "IIN0", "IIN1", "IIN2", "IIN3", "IIN4", "IIN5", "IIN6", "IIN7", "IIN8", "IIN9", "IIN10", "IIN11", "IIN12", "IIN13", "IIN14", "IIN15", }; /** * devm_idio_16_regmap_register - Register an IDIO-16 GPIO device * @dev: device that is registering this IDIO-16 GPIO device * @config: configuration for idio_16_regmap_config * * Registers an IDIO-16 GPIO device. Returns 0 on success and negative error number on failure. */ int devm_idio_16_regmap_register(struct device *const dev, const struct idio_16_regmap_config *const config) { struct gpio_regmap_config gpio_config = {}; int err; struct idio_16_data *data; struct regmap_irq_chip *chip; struct regmap_irq_chip_data *chip_data; if (!config->parent) return -EINVAL; if (!config->map) return -EINVAL; if (!config->regmap_irqs) return -EINVAL; data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); if (!data) return -ENOMEM; data->map = config->map; chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL); if (!chip) return -ENOMEM; chip->name = dev_name(dev); chip->status_base = IDIO_16_INTERRUPT_STATUS; chip->mask_base = IDIO_16_ENABLE_IRQ; chip->ack_base = IDIO_16_CLEAR_INTERRUPT; chip->no_status = config->no_status; chip->num_regs = 1; chip->irqs = config->regmap_irqs; chip->num_irqs = config->num_regmap_irqs; chip->handle_mask_sync = idio_16_handle_mask_sync; chip->irq_drv_data = data; /* Disable IRQ to prevent spurious interrupts before we're ready */ err = regmap_write(data->map, IDIO_16_DISABLE_IRQ, 0x00); if (err) return err; err = devm_regmap_add_irq_chip(dev, data->map, config->irq, 0, 0, chip, &chip_data); if (err) return dev_err_probe(dev, err, "IRQ registration failed\n"); if (config->filters) { /* Deactivate input filters */ err = regmap_write(data->map, IDIO_16_DEACTIVATE_INPUT_FILTERS, 0x00); if (err) return err; } gpio_config.parent = config->parent; gpio_config.regmap = data->map; gpio_config.ngpio = IDIO_16_NGPIO; gpio_config.names = idio_16_names; gpio_config.reg_dat_base = GPIO_REGMAP_ADDR(IDIO_16_DAT_BASE); gpio_config.reg_set_base = GPIO_REGMAP_ADDR(IDIO_16_DAT_BASE); gpio_config.ngpio_per_reg = IDIO_16_NGPIO_PER_REG; gpio_config.reg_stride = IDIO_16_REG_STRIDE; gpio_config.irq_domain = regmap_irq_get_domain(chip_data); gpio_config.reg_mask_xlate = idio_16_reg_mask_xlate; return PTR_ERR_OR_ZERO(devm_gpio_regmap_register(dev, &gpio_config)); } EXPORT_SYMBOL_GPL(devm_idio_16_regmap_register); MODULE_AUTHOR("William Breathitt Gray"); MODULE_DESCRIPTION("ACCES IDIO-16 GPIO Library"); MODULE_LICENSE("GPL"); |