1 /* 2 * Copyright (C) 2005 Sascha Hauer, Pengutronix 3 * Copyright (C) 2007 Wolfgang Grandegger <wg@grandegger.com> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the version 2 of the GNU General Public License 7 * as published by the Free Software Foundation 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, see <http://www.gnu.org/licenses/>. 16 */ 17 18 #include <linux/kernel.h> 19 #include <linux/module.h> 20 #include <linux/interrupt.h> 21 #include <linux/netdevice.h> 22 #include <linux/delay.h> 23 #include <linux/pci.h> 24 #include <linux/platform_device.h> 25 #include <linux/irq.h> 26 #include <linux/can/dev.h> 27 #include <linux/can/platform/sja1000.h> 28 #include <linux/io.h> 29 #include <linux/of.h> 30 #include <linux/of_device.h> 31 #include <linux/of_irq.h> 32 33 #include "sja1000.h" 34 35 #define DRV_NAME "sja1000_platform" 36 #define SP_CAN_CLOCK (16000000 / 2) 37 38 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>"); 39 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>"); 40 MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the platform bus"); 41 MODULE_ALIAS("platform:" DRV_NAME); 42 MODULE_LICENSE("GPL v2"); 43 44 struct sja1000_of_data { 45 size_t priv_sz; 46 int (*init)(struct sja1000_priv *priv, struct device_node *of); 47 }; 48 49 struct technologic_priv { 50 spinlock_t io_lock; 51 }; 52 53 static u8 sp_read_reg8(const struct sja1000_priv *priv, int reg) 54 { 55 return ioread8(priv->reg_base + reg); 56 } 57 58 static void sp_write_reg8(const struct sja1000_priv *priv, int reg, u8 val) 59 { 60 iowrite8(val, priv->reg_base + reg); 61 } 62 63 static u8 sp_read_reg16(const struct sja1000_priv *priv, int reg) 64 { 65 return ioread8(priv->reg_base + reg * 2); 66 } 67 68 static void sp_write_reg16(const struct sja1000_priv *priv, int reg, u8 val) 69 { 70 iowrite8(val, priv->reg_base + reg * 2); 71 } 72 73 static u8 sp_read_reg32(const struct sja1000_priv *priv, int reg) 74 { 75 return ioread8(priv->reg_base + reg * 4); 76 } 77 78 static void sp_write_reg32(const struct sja1000_priv *priv, int reg, u8 val) 79 { 80 iowrite8(val, priv->reg_base + reg * 4); 81 } 82 83 static u8 sp_technologic_read_reg16(const struct sja1000_priv *priv, int reg) 84 { 85 struct technologic_priv *tp = priv->priv; 86 unsigned long flags; 87 u8 val; 88 89 spin_lock_irqsave(&tp->io_lock, flags); 90 iowrite16(reg, priv->reg_base + 0); 91 val = ioread16(priv->reg_base + 2); 92 spin_unlock_irqrestore(&tp->io_lock, flags); 93 94 return val; 95 } 96 97 static void sp_technologic_write_reg16(const struct sja1000_priv *priv, 98 int reg, u8 val) 99 { 100 struct technologic_priv *tp = priv->priv; 101 unsigned long flags; 102 103 spin_lock_irqsave(&tp->io_lock, flags); 104 iowrite16(reg, priv->reg_base + 0); 105 iowrite16(val, priv->reg_base + 2); 106 spin_unlock_irqrestore(&tp->io_lock, flags); 107 } 108 109 static int sp_technologic_init(struct sja1000_priv *priv, struct device_node *of) 110 { 111 struct technologic_priv *tp = priv->priv; 112 113 priv->read_reg = sp_technologic_read_reg16; 114 priv->write_reg = sp_technologic_write_reg16; 115 spin_lock_init(&tp->io_lock); 116 117 return 0; 118 } 119 120 static void sp_populate(struct sja1000_priv *priv, 121 struct sja1000_platform_data *pdata, 122 unsigned long resource_mem_flags) 123 { 124 /* The CAN clock frequency is half the oscillator clock frequency */ 125 priv->can.clock.freq = pdata->osc_freq / 2; 126 priv->ocr = pdata->ocr; 127 priv->cdr = pdata->cdr; 128 129 switch (resource_mem_flags & IORESOURCE_MEM_TYPE_MASK) { 130 case IORESOURCE_MEM_32BIT: 131 priv->read_reg = sp_read_reg32; 132 priv->write_reg = sp_write_reg32; 133 break; 134 case IORESOURCE_MEM_16BIT: 135 priv->read_reg = sp_read_reg16; 136 priv->write_reg = sp_write_reg16; 137 break; 138 case IORESOURCE_MEM_8BIT: 139 default: 140 priv->read_reg = sp_read_reg8; 141 priv->write_reg = sp_write_reg8; 142 break; 143 } 144 } 145 146 static void sp_populate_of(struct sja1000_priv *priv, struct device_node *of) 147 { 148 int err; 149 u32 prop; 150 151 err = of_property_read_u32(of, "reg-io-width", &prop); 152 if (err) 153 prop = 1; /* 8 bit is default */ 154 155 switch (prop) { 156 case 4: 157 priv->read_reg = sp_read_reg32; 158 priv->write_reg = sp_write_reg32; 159 break; 160 case 2: 161 priv->read_reg = sp_read_reg16; 162 priv->write_reg = sp_write_reg16; 163 break; 164 case 1: /* fallthrough */ 165 default: 166 priv->read_reg = sp_read_reg8; 167 priv->write_reg = sp_write_reg8; 168 } 169 170 err = of_property_read_u32(of, "nxp,external-clock-frequency", &prop); 171 if (!err) 172 priv->can.clock.freq = prop / 2; 173 else 174 priv->can.clock.freq = SP_CAN_CLOCK; /* default */ 175 176 err = of_property_read_u32(of, "nxp,tx-output-mode", &prop); 177 if (!err) 178 priv->ocr |= prop & OCR_MODE_MASK; 179 else 180 priv->ocr |= OCR_MODE_NORMAL; /* default */ 181 182 err = of_property_read_u32(of, "nxp,tx-output-config", &prop); 183 if (!err) 184 priv->ocr |= (prop << OCR_TX_SHIFT) & OCR_TX_MASK; 185 else 186 priv->ocr |= OCR_TX0_PULLDOWN; /* default */ 187 188 err = of_property_read_u32(of, "nxp,clock-out-frequency", &prop); 189 if (!err && prop) { 190 u32 divider = priv->can.clock.freq * 2 / prop; 191 192 if (divider > 1) 193 priv->cdr |= divider / 2 - 1; 194 else 195 priv->cdr |= CDR_CLKOUT_MASK; 196 } else { 197 priv->cdr |= CDR_CLK_OFF; /* default */ 198 } 199 200 if (!of_property_read_bool(of, "nxp,no-comparator-bypass")) 201 priv->cdr |= CDR_CBP; /* default */ 202 } 203 204 static struct sja1000_of_data technologic_data = { 205 .priv_sz = sizeof(struct technologic_priv), 206 .init = sp_technologic_init, 207 }; 208 209 static const struct of_device_id sp_of_table[] = { 210 { .compatible = "nxp,sja1000", .data = NULL, }, 211 { .compatible = "technologic,sja1000", .data = &technologic_data, }, 212 { /* sentinel */ }, 213 }; 214 MODULE_DEVICE_TABLE(of, sp_of_table); 215 216 static int sp_probe(struct platform_device *pdev) 217 { 218 int err, irq = 0; 219 void __iomem *addr; 220 struct net_device *dev; 221 struct sja1000_priv *priv; 222 struct resource *res_mem, *res_irq = NULL; 223 struct sja1000_platform_data *pdata; 224 struct device_node *of = pdev->dev.of_node; 225 const struct of_device_id *of_id; 226 const struct sja1000_of_data *of_data = NULL; 227 size_t priv_sz = 0; 228 229 pdata = dev_get_platdata(&pdev->dev); 230 if (!pdata && !of) { 231 dev_err(&pdev->dev, "No platform data provided!\n"); 232 return -ENODEV; 233 } 234 235 res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); 236 if (!res_mem) 237 return -ENODEV; 238 239 if (!devm_request_mem_region(&pdev->dev, res_mem->start, 240 resource_size(res_mem), DRV_NAME)) 241 return -EBUSY; 242 243 addr = devm_ioremap_nocache(&pdev->dev, res_mem->start, 244 resource_size(res_mem)); 245 if (!addr) 246 return -ENOMEM; 247 248 if (of) 249 irq = irq_of_parse_and_map(of, 0); 250 else 251 res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); 252 253 if (!irq && !res_irq) 254 return -ENODEV; 255 256 of_id = of_match_device(sp_of_table, &pdev->dev); 257 if (of_id && of_id->data) { 258 of_data = of_id->data; 259 priv_sz = of_data->priv_sz; 260 } 261 262 dev = alloc_sja1000dev(priv_sz); 263 if (!dev) 264 return -ENOMEM; 265 priv = netdev_priv(dev); 266 267 if (res_irq) { 268 irq = res_irq->start; 269 priv->irq_flags = res_irq->flags & IRQF_TRIGGER_MASK; 270 if (res_irq->flags & IORESOURCE_IRQ_SHAREABLE) 271 priv->irq_flags |= IRQF_SHARED; 272 } else { 273 priv->irq_flags = IRQF_SHARED; 274 } 275 276 dev->irq = irq; 277 priv->reg_base = addr; 278 279 if (of) { 280 sp_populate_of(priv, of); 281 282 if (of_data && of_data->init) { 283 err = of_data->init(priv, of); 284 if (err) 285 goto exit_free; 286 } 287 } else { 288 sp_populate(priv, pdata, res_mem->flags); 289 } 290 291 platform_set_drvdata(pdev, dev); 292 SET_NETDEV_DEV(dev, &pdev->dev); 293 294 err = register_sja1000dev(dev); 295 if (err) { 296 dev_err(&pdev->dev, "registering %s failed (err=%d)\n", 297 DRV_NAME, err); 298 goto exit_free; 299 } 300 301 dev_info(&pdev->dev, "%s device registered (reg_base=%p, irq=%d)\n", 302 DRV_NAME, priv->reg_base, dev->irq); 303 return 0; 304 305 exit_free: 306 free_sja1000dev(dev); 307 return err; 308 } 309 310 static int sp_remove(struct platform_device *pdev) 311 { 312 struct net_device *dev = platform_get_drvdata(pdev); 313 314 unregister_sja1000dev(dev); 315 free_sja1000dev(dev); 316 317 return 0; 318 } 319 320 static struct platform_driver sp_driver = { 321 .probe = sp_probe, 322 .remove = sp_remove, 323 .driver = { 324 .name = DRV_NAME, 325 .of_match_table = sp_of_table, 326 }, 327 }; 328 329 module_platform_driver(sp_driver); 330