1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2005 Sascha Hauer, Pengutronix 4 * Copyright (C) 2007 Wolfgang Grandegger <wg@grandegger.com> 5 */ 6 7 #include <linux/kernel.h> 8 #include <linux/module.h> 9 #include <linux/interrupt.h> 10 #include <linux/netdevice.h> 11 #include <linux/delay.h> 12 #include <linux/pci.h> 13 #include <linux/platform_device.h> 14 #include <linux/irq.h> 15 #include <linux/can/dev.h> 16 #include <linux/can/platform/sja1000.h> 17 #include <linux/io.h> 18 #include <linux/of.h> 19 #include <linux/of_device.h> 20 #include <linux/of_irq.h> 21 22 #include "sja1000.h" 23 24 #define DRV_NAME "sja1000_platform" 25 #define SP_CAN_CLOCK (16000000 / 2) 26 27 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>"); 28 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>"); 29 MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the platform bus"); 30 MODULE_ALIAS("platform:" DRV_NAME); 31 MODULE_LICENSE("GPL v2"); 32 33 struct sja1000_of_data { 34 size_t priv_sz; 35 int (*init)(struct sja1000_priv *priv, struct device_node *of); 36 }; 37 38 struct technologic_priv { 39 spinlock_t io_lock; 40 }; 41 42 static u8 sp_read_reg8(const struct sja1000_priv *priv, int reg) 43 { 44 return ioread8(priv->reg_base + reg); 45 } 46 47 static void sp_write_reg8(const struct sja1000_priv *priv, int reg, u8 val) 48 { 49 iowrite8(val, priv->reg_base + reg); 50 } 51 52 static u8 sp_read_reg16(const struct sja1000_priv *priv, int reg) 53 { 54 return ioread8(priv->reg_base + reg * 2); 55 } 56 57 static void sp_write_reg16(const struct sja1000_priv *priv, int reg, u8 val) 58 { 59 iowrite8(val, priv->reg_base + reg * 2); 60 } 61 62 static u8 sp_read_reg32(const struct sja1000_priv *priv, int reg) 63 { 64 return ioread8(priv->reg_base + reg * 4); 65 } 66 67 static void sp_write_reg32(const struct sja1000_priv *priv, int reg, u8 val) 68 { 69 iowrite8(val, priv->reg_base + reg * 4); 70 } 71 72 static u8 sp_technologic_read_reg16(const struct sja1000_priv *priv, int reg) 73 { 74 struct technologic_priv *tp = priv->priv; 75 unsigned long flags; 76 u8 val; 77 78 spin_lock_irqsave(&tp->io_lock, flags); 79 iowrite16(reg, priv->reg_base + 0); 80 val = ioread16(priv->reg_base + 2); 81 spin_unlock_irqrestore(&tp->io_lock, flags); 82 83 return val; 84 } 85 86 static void sp_technologic_write_reg16(const struct sja1000_priv *priv, 87 int reg, u8 val) 88 { 89 struct technologic_priv *tp = priv->priv; 90 unsigned long flags; 91 92 spin_lock_irqsave(&tp->io_lock, flags); 93 iowrite16(reg, priv->reg_base + 0); 94 iowrite16(val, priv->reg_base + 2); 95 spin_unlock_irqrestore(&tp->io_lock, flags); 96 } 97 98 static int sp_technologic_init(struct sja1000_priv *priv, struct device_node *of) 99 { 100 struct technologic_priv *tp = priv->priv; 101 102 priv->read_reg = sp_technologic_read_reg16; 103 priv->write_reg = sp_technologic_write_reg16; 104 spin_lock_init(&tp->io_lock); 105 106 return 0; 107 } 108 109 static void sp_populate(struct sja1000_priv *priv, 110 struct sja1000_platform_data *pdata, 111 unsigned long resource_mem_flags) 112 { 113 /* The CAN clock frequency is half the oscillator clock frequency */ 114 priv->can.clock.freq = pdata->osc_freq / 2; 115 priv->ocr = pdata->ocr; 116 priv->cdr = pdata->cdr; 117 118 switch (resource_mem_flags & IORESOURCE_MEM_TYPE_MASK) { 119 case IORESOURCE_MEM_32BIT: 120 priv->read_reg = sp_read_reg32; 121 priv->write_reg = sp_write_reg32; 122 break; 123 case IORESOURCE_MEM_16BIT: 124 priv->read_reg = sp_read_reg16; 125 priv->write_reg = sp_write_reg16; 126 break; 127 case IORESOURCE_MEM_8BIT: 128 default: 129 priv->read_reg = sp_read_reg8; 130 priv->write_reg = sp_write_reg8; 131 break; 132 } 133 } 134 135 static void sp_populate_of(struct sja1000_priv *priv, struct device_node *of) 136 { 137 int err; 138 u32 prop; 139 140 err = of_property_read_u32(of, "reg-io-width", &prop); 141 if (err) 142 prop = 1; /* 8 bit is default */ 143 144 switch (prop) { 145 case 4: 146 priv->read_reg = sp_read_reg32; 147 priv->write_reg = sp_write_reg32; 148 break; 149 case 2: 150 priv->read_reg = sp_read_reg16; 151 priv->write_reg = sp_write_reg16; 152 break; 153 case 1: 154 default: 155 priv->read_reg = sp_read_reg8; 156 priv->write_reg = sp_write_reg8; 157 } 158 159 err = of_property_read_u32(of, "nxp,external-clock-frequency", &prop); 160 if (!err) 161 priv->can.clock.freq = prop / 2; 162 else 163 priv->can.clock.freq = SP_CAN_CLOCK; /* default */ 164 165 err = of_property_read_u32(of, "nxp,tx-output-mode", &prop); 166 if (!err) 167 priv->ocr |= prop & OCR_MODE_MASK; 168 else 169 priv->ocr |= OCR_MODE_NORMAL; /* default */ 170 171 err = of_property_read_u32(of, "nxp,tx-output-config", &prop); 172 if (!err) 173 priv->ocr |= (prop << OCR_TX_SHIFT) & OCR_TX_MASK; 174 else 175 priv->ocr |= OCR_TX0_PULLDOWN; /* default */ 176 177 err = of_property_read_u32(of, "nxp,clock-out-frequency", &prop); 178 if (!err && prop) { 179 u32 divider = priv->can.clock.freq * 2 / prop; 180 181 if (divider > 1) 182 priv->cdr |= divider / 2 - 1; 183 else 184 priv->cdr |= CDR_CLKOUT_MASK; 185 } else { 186 priv->cdr |= CDR_CLK_OFF; /* default */ 187 } 188 189 if (!of_property_read_bool(of, "nxp,no-comparator-bypass")) 190 priv->cdr |= CDR_CBP; /* default */ 191 } 192 193 static struct sja1000_of_data technologic_data = { 194 .priv_sz = sizeof(struct technologic_priv), 195 .init = sp_technologic_init, 196 }; 197 198 static const struct of_device_id sp_of_table[] = { 199 { .compatible = "nxp,sja1000", .data = NULL, }, 200 { .compatible = "technologic,sja1000", .data = &technologic_data, }, 201 { /* sentinel */ }, 202 }; 203 MODULE_DEVICE_TABLE(of, sp_of_table); 204 205 static int sp_probe(struct platform_device *pdev) 206 { 207 int err, irq = 0; 208 void __iomem *addr; 209 struct net_device *dev; 210 struct sja1000_priv *priv; 211 struct resource *res_mem, *res_irq = NULL; 212 struct sja1000_platform_data *pdata; 213 struct device_node *of = pdev->dev.of_node; 214 const struct of_device_id *of_id; 215 const struct sja1000_of_data *of_data = NULL; 216 size_t priv_sz = 0; 217 218 pdata = dev_get_platdata(&pdev->dev); 219 if (!pdata && !of) { 220 dev_err(&pdev->dev, "No platform data provided!\n"); 221 return -ENODEV; 222 } 223 224 res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); 225 if (!res_mem) 226 return -ENODEV; 227 228 if (!devm_request_mem_region(&pdev->dev, res_mem->start, 229 resource_size(res_mem), DRV_NAME)) 230 return -EBUSY; 231 232 addr = devm_ioremap(&pdev->dev, res_mem->start, 233 resource_size(res_mem)); 234 if (!addr) 235 return -ENOMEM; 236 237 if (of) 238 irq = irq_of_parse_and_map(of, 0); 239 else 240 res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); 241 242 if (!irq && !res_irq) 243 return -ENODEV; 244 245 of_id = of_match_device(sp_of_table, &pdev->dev); 246 if (of_id && of_id->data) { 247 of_data = of_id->data; 248 priv_sz = of_data->priv_sz; 249 } 250 251 dev = alloc_sja1000dev(priv_sz); 252 if (!dev) 253 return -ENOMEM; 254 priv = netdev_priv(dev); 255 256 if (res_irq) { 257 irq = res_irq->start; 258 priv->irq_flags = res_irq->flags & IRQF_TRIGGER_MASK; 259 if (res_irq->flags & IORESOURCE_IRQ_SHAREABLE) 260 priv->irq_flags |= IRQF_SHARED; 261 } else { 262 priv->irq_flags = IRQF_SHARED; 263 } 264 265 dev->irq = irq; 266 priv->reg_base = addr; 267 268 if (of) { 269 sp_populate_of(priv, of); 270 271 if (of_data && of_data->init) { 272 err = of_data->init(priv, of); 273 if (err) 274 goto exit_free; 275 } 276 } else { 277 sp_populate(priv, pdata, res_mem->flags); 278 } 279 280 platform_set_drvdata(pdev, dev); 281 SET_NETDEV_DEV(dev, &pdev->dev); 282 283 err = register_sja1000dev(dev); 284 if (err) { 285 dev_err(&pdev->dev, "registering %s failed (err=%d)\n", 286 DRV_NAME, err); 287 goto exit_free; 288 } 289 290 dev_info(&pdev->dev, "%s device registered (reg_base=%p, irq=%d)\n", 291 DRV_NAME, priv->reg_base, dev->irq); 292 return 0; 293 294 exit_free: 295 free_sja1000dev(dev); 296 return err; 297 } 298 299 static int sp_remove(struct platform_device *pdev) 300 { 301 struct net_device *dev = platform_get_drvdata(pdev); 302 303 unregister_sja1000dev(dev); 304 free_sja1000dev(dev); 305 306 return 0; 307 } 308 309 static struct platform_driver sp_driver = { 310 .probe = sp_probe, 311 .remove = sp_remove, 312 .driver = { 313 .name = DRV_NAME, 314 .of_match_table = sp_of_table, 315 }, 316 }; 317 318 module_platform_driver(sp_driver); 319