1 /* 2 * SPI driver for Micrel/Kendin KS8995M and KSZ8864RMN ethernet switches 3 * 4 * Copyright (C) 2008 Gabor Juhos <juhosg at openwrt.org> 5 * 6 * This file was based on: drivers/spi/at25.c 7 * Copyright (C) 2006 David Brownell 8 * 9 * This program is free software; you can redistribute it and/or modify it 10 * under the terms of the GNU General Public License version 2 as published 11 * by the Free Software Foundation. 12 */ 13 14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 15 16 #include <linux/types.h> 17 #include <linux/kernel.h> 18 #include <linux/module.h> 19 #include <linux/delay.h> 20 #include <linux/device.h> 21 22 #include <linux/spi/spi.h> 23 24 #define DRV_VERSION "0.1.1" 25 #define DRV_DESC "Micrel KS8995 Ethernet switch SPI driver" 26 27 /* ------------------------------------------------------------------------ */ 28 29 #define KS8995_REG_ID0 0x00 /* Chip ID0 */ 30 #define KS8995_REG_ID1 0x01 /* Chip ID1 */ 31 32 #define KS8995_REG_GC0 0x02 /* Global Control 0 */ 33 #define KS8995_REG_GC1 0x03 /* Global Control 1 */ 34 #define KS8995_REG_GC2 0x04 /* Global Control 2 */ 35 #define KS8995_REG_GC3 0x05 /* Global Control 3 */ 36 #define KS8995_REG_GC4 0x06 /* Global Control 4 */ 37 #define KS8995_REG_GC5 0x07 /* Global Control 5 */ 38 #define KS8995_REG_GC6 0x08 /* Global Control 6 */ 39 #define KS8995_REG_GC7 0x09 /* Global Control 7 */ 40 #define KS8995_REG_GC8 0x0a /* Global Control 8 */ 41 #define KS8995_REG_GC9 0x0b /* Global Control 9 */ 42 43 #define KS8995_REG_PC(p, r) ((0x10 * p) + r) /* Port Control */ 44 #define KS8995_REG_PS(p, r) ((0x10 * p) + r + 0xe) /* Port Status */ 45 46 #define KS8995_REG_TPC0 0x60 /* TOS Priority Control 0 */ 47 #define KS8995_REG_TPC1 0x61 /* TOS Priority Control 1 */ 48 #define KS8995_REG_TPC2 0x62 /* TOS Priority Control 2 */ 49 #define KS8995_REG_TPC3 0x63 /* TOS Priority Control 3 */ 50 #define KS8995_REG_TPC4 0x64 /* TOS Priority Control 4 */ 51 #define KS8995_REG_TPC5 0x65 /* TOS Priority Control 5 */ 52 #define KS8995_REG_TPC6 0x66 /* TOS Priority Control 6 */ 53 #define KS8995_REG_TPC7 0x67 /* TOS Priority Control 7 */ 54 55 #define KS8995_REG_MAC0 0x68 /* MAC address 0 */ 56 #define KS8995_REG_MAC1 0x69 /* MAC address 1 */ 57 #define KS8995_REG_MAC2 0x6a /* MAC address 2 */ 58 #define KS8995_REG_MAC3 0x6b /* MAC address 3 */ 59 #define KS8995_REG_MAC4 0x6c /* MAC address 4 */ 60 #define KS8995_REG_MAC5 0x6d /* MAC address 5 */ 61 62 #define KS8995_REG_IAC0 0x6e /* Indirect Access Control 0 */ 63 #define KS8995_REG_IAC1 0x6f /* Indirect Access Control 0 */ 64 #define KS8995_REG_IAD7 0x70 /* Indirect Access Data 7 */ 65 #define KS8995_REG_IAD6 0x71 /* Indirect Access Data 6 */ 66 #define KS8995_REG_IAD5 0x72 /* Indirect Access Data 5 */ 67 #define KS8995_REG_IAD4 0x73 /* Indirect Access Data 4 */ 68 #define KS8995_REG_IAD3 0x74 /* Indirect Access Data 3 */ 69 #define KS8995_REG_IAD2 0x75 /* Indirect Access Data 2 */ 70 #define KS8995_REG_IAD1 0x76 /* Indirect Access Data 1 */ 71 #define KS8995_REG_IAD0 0x77 /* Indirect Access Data 0 */ 72 73 #define KSZ8864_REG_ID1 0xfe /* Chip ID in bit 7 */ 74 75 #define KS8995_REGS_SIZE 0x80 76 #define KSZ8864_REGS_SIZE 0x100 77 78 #define ID1_CHIPID_M 0xf 79 #define ID1_CHIPID_S 4 80 #define ID1_REVISION_M 0x7 81 #define ID1_REVISION_S 1 82 #define ID1_START_SW 1 /* start the switch */ 83 84 #define FAMILY_KS8995 0x95 85 #define CHIPID_M 0 86 87 #define KS8995_CMD_WRITE 0x02U 88 #define KS8995_CMD_READ 0x03U 89 90 #define KS8995_RESET_DELAY 10 /* usec */ 91 92 struct ks8995_pdata { 93 /* not yet implemented */ 94 }; 95 96 struct ks8995_switch { 97 struct spi_device *spi; 98 struct mutex lock; 99 struct ks8995_pdata *pdata; 100 struct bin_attribute regs_attr; 101 }; 102 103 static inline u8 get_chip_id(u8 val) 104 { 105 return (val >> ID1_CHIPID_S) & ID1_CHIPID_M; 106 } 107 108 static inline u8 get_chip_rev(u8 val) 109 { 110 return (val >> ID1_REVISION_S) & ID1_REVISION_M; 111 } 112 113 /* ------------------------------------------------------------------------ */ 114 static int ks8995_read(struct ks8995_switch *ks, char *buf, 115 unsigned offset, size_t count) 116 { 117 u8 cmd[2]; 118 struct spi_transfer t[2]; 119 struct spi_message m; 120 int err; 121 122 spi_message_init(&m); 123 124 memset(&t, 0, sizeof(t)); 125 126 t[0].tx_buf = cmd; 127 t[0].len = sizeof(cmd); 128 spi_message_add_tail(&t[0], &m); 129 130 t[1].rx_buf = buf; 131 t[1].len = count; 132 spi_message_add_tail(&t[1], &m); 133 134 cmd[0] = KS8995_CMD_READ; 135 cmd[1] = offset; 136 137 mutex_lock(&ks->lock); 138 err = spi_sync(ks->spi, &m); 139 mutex_unlock(&ks->lock); 140 141 return err ? err : count; 142 } 143 144 145 static int ks8995_write(struct ks8995_switch *ks, char *buf, 146 unsigned offset, size_t count) 147 { 148 u8 cmd[2]; 149 struct spi_transfer t[2]; 150 struct spi_message m; 151 int err; 152 153 spi_message_init(&m); 154 155 memset(&t, 0, sizeof(t)); 156 157 t[0].tx_buf = cmd; 158 t[0].len = sizeof(cmd); 159 spi_message_add_tail(&t[0], &m); 160 161 t[1].tx_buf = buf; 162 t[1].len = count; 163 spi_message_add_tail(&t[1], &m); 164 165 cmd[0] = KS8995_CMD_WRITE; 166 cmd[1] = offset; 167 168 mutex_lock(&ks->lock); 169 err = spi_sync(ks->spi, &m); 170 mutex_unlock(&ks->lock); 171 172 return err ? err : count; 173 } 174 175 static inline int ks8995_read_reg(struct ks8995_switch *ks, u8 addr, u8 *buf) 176 { 177 return ks8995_read(ks, buf, addr, 1) != 1; 178 } 179 180 static inline int ks8995_write_reg(struct ks8995_switch *ks, u8 addr, u8 val) 181 { 182 char buf = val; 183 184 return ks8995_write(ks, &buf, addr, 1) != 1; 185 } 186 187 /* ------------------------------------------------------------------------ */ 188 189 static int ks8995_stop(struct ks8995_switch *ks) 190 { 191 return ks8995_write_reg(ks, KS8995_REG_ID1, 0); 192 } 193 194 static int ks8995_start(struct ks8995_switch *ks) 195 { 196 return ks8995_write_reg(ks, KS8995_REG_ID1, 1); 197 } 198 199 static int ks8995_reset(struct ks8995_switch *ks) 200 { 201 int err; 202 203 err = ks8995_stop(ks); 204 if (err) 205 return err; 206 207 udelay(KS8995_RESET_DELAY); 208 209 return ks8995_start(ks); 210 } 211 212 static ssize_t ks8995_registers_read(struct file *filp, struct kobject *kobj, 213 struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count) 214 { 215 struct device *dev; 216 struct ks8995_switch *ks8995; 217 218 dev = container_of(kobj, struct device, kobj); 219 ks8995 = dev_get_drvdata(dev); 220 221 return ks8995_read(ks8995, buf, off, count); 222 } 223 224 static ssize_t ks8995_registers_write(struct file *filp, struct kobject *kobj, 225 struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count) 226 { 227 struct device *dev; 228 struct ks8995_switch *ks8995; 229 230 dev = container_of(kobj, struct device, kobj); 231 ks8995 = dev_get_drvdata(dev); 232 233 return ks8995_write(ks8995, buf, off, count); 234 } 235 236 static const struct bin_attribute ks8995_registers_attr = { 237 .attr = { 238 .name = "registers", 239 .mode = S_IRUSR | S_IWUSR, 240 }, 241 .size = KS8995_REGS_SIZE, 242 .read = ks8995_registers_read, 243 .write = ks8995_registers_write, 244 }; 245 246 /* ------------------------------------------------------------------------ */ 247 248 static int ks8995_probe(struct spi_device *spi) 249 { 250 struct ks8995_switch *ks; 251 struct ks8995_pdata *pdata; 252 u8 ids[2]; 253 int err; 254 255 /* Chip description */ 256 pdata = spi->dev.platform_data; 257 258 ks = devm_kzalloc(&spi->dev, sizeof(*ks), GFP_KERNEL); 259 if (!ks) 260 return -ENOMEM; 261 262 mutex_init(&ks->lock); 263 ks->pdata = pdata; 264 ks->spi = spi_dev_get(spi); 265 spi_set_drvdata(spi, ks); 266 267 spi->mode = SPI_MODE_0; 268 spi->bits_per_word = 8; 269 err = spi_setup(spi); 270 if (err) { 271 dev_err(&spi->dev, "spi_setup failed, err=%d\n", err); 272 return err; 273 } 274 275 err = ks8995_read(ks, ids, KS8995_REG_ID0, sizeof(ids)); 276 if (err < 0) { 277 dev_err(&spi->dev, "unable to read id registers, err=%d\n", 278 err); 279 return err; 280 } 281 282 switch (ids[0]) { 283 case FAMILY_KS8995: 284 break; 285 default: 286 dev_err(&spi->dev, "unknown family id:%02x\n", ids[0]); 287 return -ENODEV; 288 } 289 290 memcpy(&ks->regs_attr, &ks8995_registers_attr, sizeof(ks->regs_attr)); 291 if (get_chip_id(ids[1]) != CHIPID_M) { 292 u8 val; 293 294 /* Check if this is a KSZ8864RMN */ 295 err = ks8995_read(ks, &val, KSZ8864_REG_ID1, sizeof(val)); 296 if (err < 0) { 297 dev_err(&spi->dev, 298 "unable to read chip id register, err=%d\n", 299 err); 300 return err; 301 } 302 if ((val & 0x80) == 0) { 303 dev_err(&spi->dev, "unknown chip:%02x,0\n", ids[1]); 304 return err; 305 } 306 ks->regs_attr.size = KSZ8864_REGS_SIZE; 307 } 308 309 err = ks8995_reset(ks); 310 if (err) 311 return err; 312 313 err = sysfs_create_bin_file(&spi->dev.kobj, &ks->regs_attr); 314 if (err) { 315 dev_err(&spi->dev, "unable to create sysfs file, err=%d\n", 316 err); 317 return err; 318 } 319 320 if (get_chip_id(ids[1]) == CHIPID_M) { 321 dev_info(&spi->dev, 322 "KS8995 device found, Chip ID:%x, Revision:%x\n", 323 get_chip_id(ids[1]), get_chip_rev(ids[1])); 324 } else { 325 dev_info(&spi->dev, "KSZ8864 device found, Revision:%x\n", 326 get_chip_rev(ids[1])); 327 } 328 329 return 0; 330 } 331 332 static int ks8995_remove(struct spi_device *spi) 333 { 334 struct ks8995_switch *ks = spi_get_drvdata(spi); 335 336 sysfs_remove_bin_file(&spi->dev.kobj, &ks->regs_attr); 337 338 return 0; 339 } 340 341 /* ------------------------------------------------------------------------ */ 342 343 static struct spi_driver ks8995_driver = { 344 .driver = { 345 .name = "spi-ks8995", 346 }, 347 .probe = ks8995_probe, 348 .remove = ks8995_remove, 349 }; 350 351 module_spi_driver(ks8995_driver); 352 353 MODULE_DESCRIPTION(DRV_DESC); 354 MODULE_VERSION(DRV_VERSION); 355 MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>"); 356 MODULE_LICENSE("GPL v2"); 357