1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * GPIO driver for the ACCES 104-DIO-48E series 4 * Copyright (C) 2016 William Breathitt Gray 5 * 6 * This driver supports the following ACCES devices: 104-DIO-48E and 7 * 104-DIO-24E. 8 */ 9 #include <linux/bits.h> 10 #include <linux/device.h> 11 #include <linux/err.h> 12 #include <linux/ioport.h> 13 #include <linux/irq.h> 14 #include <linux/isa.h> 15 #include <linux/kernel.h> 16 #include <linux/module.h> 17 #include <linux/moduleparam.h> 18 #include <linux/regmap.h> 19 #include <linux/types.h> 20 21 #include "gpio-i8255.h" 22 23 MODULE_IMPORT_NS(I8255); 24 25 #define DIO48E_EXTENT 16 26 #define MAX_NUM_DIO48E max_num_isa_dev(DIO48E_EXTENT) 27 28 static unsigned int base[MAX_NUM_DIO48E]; 29 static unsigned int num_dio48e; 30 module_param_hw_array(base, uint, ioport, &num_dio48e, 0); 31 MODULE_PARM_DESC(base, "ACCES 104-DIO-48E base addresses"); 32 33 static unsigned int irq[MAX_NUM_DIO48E]; 34 static unsigned int num_irq; 35 module_param_hw_array(irq, uint, irq, &num_irq, 0); 36 MODULE_PARM_DESC(irq, "ACCES 104-DIO-48E interrupt line numbers"); 37 38 #define DIO48E_ENABLE_INTERRUPT 0xB 39 #define DIO48E_DISABLE_INTERRUPT DIO48E_ENABLE_INTERRUPT 40 #define DIO48E_CLEAR_INTERRUPT 0xF 41 42 #define DIO48E_NUM_PPI 2 43 44 static const struct regmap_range dio48e_wr_ranges[] = { 45 regmap_reg_range(0x0, 0x9), regmap_reg_range(0xB, 0xB), 46 regmap_reg_range(0xD, 0xD), regmap_reg_range(0xF, 0xF), 47 }; 48 static const struct regmap_range dio48e_rd_ranges[] = { 49 regmap_reg_range(0x0, 0x2), regmap_reg_range(0x4, 0x6), 50 regmap_reg_range(0xB, 0xB), regmap_reg_range(0xD, 0xD), 51 regmap_reg_range(0xF, 0xF), 52 }; 53 static const struct regmap_range dio48e_volatile_ranges[] = { 54 i8255_volatile_regmap_range(0x0), i8255_volatile_regmap_range(0x4), 55 regmap_reg_range(0xB, 0xB), regmap_reg_range(0xD, 0xD), 56 regmap_reg_range(0xF, 0xF), 57 }; 58 static const struct regmap_range dio48e_precious_ranges[] = { 59 regmap_reg_range(0xB, 0xB), regmap_reg_range(0xD, 0xD), 60 regmap_reg_range(0xF, 0xF), 61 }; 62 static const struct regmap_access_table dio48e_wr_table = { 63 .yes_ranges = dio48e_wr_ranges, 64 .n_yes_ranges = ARRAY_SIZE(dio48e_wr_ranges), 65 }; 66 static const struct regmap_access_table dio48e_rd_table = { 67 .yes_ranges = dio48e_rd_ranges, 68 .n_yes_ranges = ARRAY_SIZE(dio48e_rd_ranges), 69 }; 70 static const struct regmap_access_table dio48e_volatile_table = { 71 .yes_ranges = dio48e_volatile_ranges, 72 .n_yes_ranges = ARRAY_SIZE(dio48e_volatile_ranges), 73 }; 74 static const struct regmap_access_table dio48e_precious_table = { 75 .yes_ranges = dio48e_precious_ranges, 76 .n_yes_ranges = ARRAY_SIZE(dio48e_precious_ranges), 77 }; 78 static const struct regmap_config dio48e_regmap_config = { 79 .reg_bits = 8, 80 .reg_stride = 1, 81 .val_bits = 8, 82 .io_port = true, 83 .max_register = 0xF, 84 .wr_table = &dio48e_wr_table, 85 .rd_table = &dio48e_rd_table, 86 .volatile_table = &dio48e_volatile_table, 87 .precious_table = &dio48e_precious_table, 88 .cache_type = REGCACHE_FLAT, 89 .use_raw_spinlock = true, 90 }; 91 92 /* only bit 3 on each respective Port C supports interrupts */ 93 #define DIO48E_REGMAP_IRQ(_ppi) \ 94 [19 + (_ppi) * 24] = { \ 95 .mask = BIT(_ppi), \ 96 .type = { .types_supported = IRQ_TYPE_EDGE_RISING }, \ 97 } 98 99 static const struct regmap_irq dio48e_regmap_irqs[] = { 100 DIO48E_REGMAP_IRQ(0), DIO48E_REGMAP_IRQ(1), 101 }; 102 103 /** 104 * struct dio48e_gpio - GPIO device private data structure 105 * @map: Regmap for the device 106 * @irq_mask: Current IRQ mask state on the device 107 */ 108 struct dio48e_gpio { 109 struct regmap *map; 110 unsigned int irq_mask; 111 }; 112 113 static int dio48e_handle_mask_sync(const int index, 114 const unsigned int mask_buf_def, 115 const unsigned int mask_buf, 116 void *const irq_drv_data) 117 { 118 struct dio48e_gpio *const dio48egpio = irq_drv_data; 119 const unsigned int prev_mask = dio48egpio->irq_mask; 120 int err; 121 unsigned int val; 122 123 /* exit early if no change since the previous mask */ 124 if (mask_buf == prev_mask) 125 return 0; 126 127 /* remember the current mask for the next mask sync */ 128 dio48egpio->irq_mask = mask_buf; 129 130 /* if all previously masked, enable interrupts when unmasking */ 131 if (prev_mask == mask_buf_def) { 132 err = regmap_write(dio48egpio->map, DIO48E_CLEAR_INTERRUPT, 0x00); 133 if (err) 134 return err; 135 return regmap_write(dio48egpio->map, DIO48E_ENABLE_INTERRUPT, 0x00); 136 } 137 138 /* if all are currently masked, disable interrupts */ 139 if (mask_buf == mask_buf_def) 140 return regmap_read(dio48egpio->map, DIO48E_DISABLE_INTERRUPT, &val); 141 142 return 0; 143 } 144 145 #define DIO48E_NGPIO 48 146 static const char *dio48e_names[DIO48E_NGPIO] = { 147 "PPI Group 0 Port A 0", "PPI Group 0 Port A 1", "PPI Group 0 Port A 2", 148 "PPI Group 0 Port A 3", "PPI Group 0 Port A 4", "PPI Group 0 Port A 5", 149 "PPI Group 0 Port A 6", "PPI Group 0 Port A 7", "PPI Group 0 Port B 0", 150 "PPI Group 0 Port B 1", "PPI Group 0 Port B 2", "PPI Group 0 Port B 3", 151 "PPI Group 0 Port B 4", "PPI Group 0 Port B 5", "PPI Group 0 Port B 6", 152 "PPI Group 0 Port B 7", "PPI Group 0 Port C 0", "PPI Group 0 Port C 1", 153 "PPI Group 0 Port C 2", "PPI Group 0 Port C 3", "PPI Group 0 Port C 4", 154 "PPI Group 0 Port C 5", "PPI Group 0 Port C 6", "PPI Group 0 Port C 7", 155 "PPI Group 1 Port A 0", "PPI Group 1 Port A 1", "PPI Group 1 Port A 2", 156 "PPI Group 1 Port A 3", "PPI Group 1 Port A 4", "PPI Group 1 Port A 5", 157 "PPI Group 1 Port A 6", "PPI Group 1 Port A 7", "PPI Group 1 Port B 0", 158 "PPI Group 1 Port B 1", "PPI Group 1 Port B 2", "PPI Group 1 Port B 3", 159 "PPI Group 1 Port B 4", "PPI Group 1 Port B 5", "PPI Group 1 Port B 6", 160 "PPI Group 1 Port B 7", "PPI Group 1 Port C 0", "PPI Group 1 Port C 1", 161 "PPI Group 1 Port C 2", "PPI Group 1 Port C 3", "PPI Group 1 Port C 4", 162 "PPI Group 1 Port C 5", "PPI Group 1 Port C 6", "PPI Group 1 Port C 7" 163 }; 164 165 static int dio48e_irq_init_hw(struct regmap *const map) 166 { 167 unsigned int val; 168 169 /* Disable IRQ by default */ 170 return regmap_read(map, DIO48E_DISABLE_INTERRUPT, &val); 171 } 172 173 static int dio48e_probe(struct device *dev, unsigned int id) 174 { 175 const char *const name = dev_name(dev); 176 struct i8255_regmap_config config = {}; 177 void __iomem *regs; 178 struct regmap *map; 179 int err; 180 struct regmap_irq_chip *chip; 181 struct dio48e_gpio *dio48egpio; 182 struct regmap_irq_chip_data *chip_data; 183 184 if (!devm_request_region(dev, base[id], DIO48E_EXTENT, name)) { 185 dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n", 186 base[id], base[id] + DIO48E_EXTENT); 187 return -EBUSY; 188 } 189 190 regs = devm_ioport_map(dev, base[id], DIO48E_EXTENT); 191 if (!regs) 192 return -ENOMEM; 193 194 map = devm_regmap_init_mmio(dev, regs, &dio48e_regmap_config); 195 if (IS_ERR(map)) 196 return dev_err_probe(dev, PTR_ERR(map), 197 "Unable to initialize register map\n"); 198 199 dio48egpio = devm_kzalloc(dev, sizeof(*dio48egpio), GFP_KERNEL); 200 if (!dio48egpio) 201 return -ENOMEM; 202 203 dio48egpio->map = map; 204 205 chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL); 206 if (!chip) 207 return -ENOMEM; 208 209 chip->name = name; 210 chip->mask_base = DIO48E_ENABLE_INTERRUPT; 211 chip->ack_base = DIO48E_CLEAR_INTERRUPT; 212 chip->no_status = true; 213 chip->num_regs = 1; 214 chip->irqs = dio48e_regmap_irqs; 215 chip->num_irqs = ARRAY_SIZE(dio48e_regmap_irqs); 216 chip->handle_mask_sync = dio48e_handle_mask_sync; 217 chip->irq_drv_data = dio48egpio; 218 219 /* Initialize to prevent spurious interrupts before we're ready */ 220 err = dio48e_irq_init_hw(map); 221 if (err) 222 return err; 223 224 err = devm_regmap_add_irq_chip(dev, map, irq[id], 0, 0, chip, &chip_data); 225 if (err) 226 return dev_err_probe(dev, err, "IRQ registration failed\n"); 227 228 config.parent = dev; 229 config.map = map; 230 config.num_ppi = DIO48E_NUM_PPI; 231 config.names = dio48e_names; 232 config.domain = regmap_irq_get_domain(chip_data); 233 234 return devm_i8255_regmap_register(dev, &config); 235 } 236 237 static struct isa_driver dio48e_driver = { 238 .probe = dio48e_probe, 239 .driver = { 240 .name = "104-dio-48e" 241 }, 242 }; 243 module_isa_driver_with_irq(dio48e_driver, num_dio48e, num_irq); 244 245 MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>"); 246 MODULE_DESCRIPTION("ACCES 104-DIO-48E GPIO driver"); 247 MODULE_LICENSE("GPL v2"); 248