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 21 #include "sja1000.h" 22 23 #define DRV_NAME "sja1000_platform" 24 #define SP_CAN_CLOCK (16000000 / 2) 25 26 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>"); 27 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>"); 28 MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the platform bus"); 29 MODULE_ALIAS("platform:" DRV_NAME); 30 MODULE_LICENSE("GPL v2"); 31 32 struct sja1000_of_data { 33 size_t priv_sz; 34 int (*init)(struct sja1000_priv *priv, struct device_node *of); 35 }; 36 37 struct technologic_priv { 38 spinlock_t io_lock; 39 }; 40 41 static u8 sp_read_reg8(const struct sja1000_priv *priv, int reg) 42 { 43 return ioread8(priv->reg_base + reg); 44 } 45 46 static void sp_write_reg8(const struct sja1000_priv *priv, int reg, u8 val) 47 { 48 iowrite8(val, priv->reg_base + reg); 49 } 50 51 static u8 sp_read_reg16(const struct sja1000_priv *priv, int reg) 52 { 53 return ioread8(priv->reg_base + reg * 2); 54 } 55 56 static void sp_write_reg16(const struct sja1000_priv *priv, int reg, u8 val) 57 { 58 iowrite8(val, priv->reg_base + reg * 2); 59 } 60 61 static u8 sp_read_reg32(const struct sja1000_priv *priv, int reg) 62 { 63 return ioread8(priv->reg_base + reg * 4); 64 } 65 66 static void sp_write_reg32(const struct sja1000_priv *priv, int reg, u8 val) 67 { 68 iowrite8(val, priv->reg_base + reg * 4); 69 } 70 71 static u8 sp_technologic_read_reg16(const struct sja1000_priv *priv, int reg) 72 { 73 struct technologic_priv *tp = priv->priv; 74 unsigned long flags; 75 u8 val; 76 77 spin_lock_irqsave(&tp->io_lock, flags); 78 iowrite16(reg, priv->reg_base + 0); 79 val = ioread16(priv->reg_base + 2); 80 spin_unlock_irqrestore(&tp->io_lock, flags); 81 82 return val; 83 } 84 85 static void sp_technologic_write_reg16(const struct sja1000_priv *priv, 86 int reg, u8 val) 87 { 88 struct technologic_priv *tp = priv->priv; 89 unsigned long flags; 90 91 spin_lock_irqsave(&tp->io_lock, flags); 92 iowrite16(reg, priv->reg_base + 0); 93 iowrite16(val, priv->reg_base + 2); 94 spin_unlock_irqrestore(&tp->io_lock, flags); 95 } 96 97 static int sp_technologic_init(struct sja1000_priv *priv, struct device_node *of) 98 { 99 struct technologic_priv *tp = priv->priv; 100 101 priv->read_reg = sp_technologic_read_reg16; 102 priv->write_reg = sp_technologic_write_reg16; 103 spin_lock_init(&tp->io_lock); 104 105 return 0; 106 } 107 108 static void sp_populate(struct sja1000_priv *priv, 109 struct sja1000_platform_data *pdata, 110 unsigned long resource_mem_flags) 111 { 112 /* The CAN clock frequency is half the oscillator clock frequency */ 113 priv->can.clock.freq = pdata->osc_freq / 2; 114 priv->ocr = pdata->ocr; 115 priv->cdr = pdata->cdr; 116 117 switch (resource_mem_flags & IORESOURCE_MEM_TYPE_MASK) { 118 case IORESOURCE_MEM_32BIT: 119 priv->read_reg = sp_read_reg32; 120 priv->write_reg = sp_write_reg32; 121 break; 122 case IORESOURCE_MEM_16BIT: 123 priv->read_reg = sp_read_reg16; 124 priv->write_reg = sp_write_reg16; 125 break; 126 case IORESOURCE_MEM_8BIT: 127 default: 128 priv->read_reg = sp_read_reg8; 129 priv->write_reg = sp_write_reg8; 130 break; 131 } 132 } 133 134 static void sp_populate_of(struct sja1000_priv *priv, struct device_node *of) 135 { 136 int err; 137 u32 prop; 138 139 err = of_property_read_u32(of, "reg-io-width", &prop); 140 if (err) 141 prop = 1; /* 8 bit is default */ 142 143 switch (prop) { 144 case 4: 145 priv->read_reg = sp_read_reg32; 146 priv->write_reg = sp_write_reg32; 147 break; 148 case 2: 149 priv->read_reg = sp_read_reg16; 150 priv->write_reg = sp_write_reg16; 151 break; 152 case 1: 153 default: 154 priv->read_reg = sp_read_reg8; 155 priv->write_reg = sp_write_reg8; 156 } 157 158 err = of_property_read_u32(of, "nxp,external-clock-frequency", &prop); 159 if (!err) 160 priv->can.clock.freq = prop / 2; 161 else 162 priv->can.clock.freq = SP_CAN_CLOCK; /* default */ 163 164 err = of_property_read_u32(of, "nxp,tx-output-mode", &prop); 165 if (!err) 166 priv->ocr |= prop & OCR_MODE_MASK; 167 else 168 priv->ocr |= OCR_MODE_NORMAL; /* default */ 169 170 err = of_property_read_u32(of, "nxp,tx-output-config", &prop); 171 if (!err) 172 priv->ocr |= (prop << OCR_TX_SHIFT) & OCR_TX_MASK; 173 else 174 priv->ocr |= OCR_TX0_PULLDOWN; /* default */ 175 176 err = of_property_read_u32(of, "nxp,clock-out-frequency", &prop); 177 if (!err && prop) { 178 u32 divider = priv->can.clock.freq * 2 / prop; 179 180 if (divider > 1) 181 priv->cdr |= divider / 2 - 1; 182 else 183 priv->cdr |= CDR_CLKOUT_MASK; 184 } else { 185 priv->cdr |= CDR_CLK_OFF; /* default */ 186 } 187 188 if (!of_property_read_bool(of, "nxp,no-comparator-bypass")) 189 priv->cdr |= CDR_CBP; /* default */ 190 } 191 192 static struct sja1000_of_data technologic_data = { 193 .priv_sz = sizeof(struct technologic_priv), 194 .init = sp_technologic_init, 195 }; 196 197 static const struct of_device_id sp_of_table[] = { 198 { .compatible = "nxp,sja1000", .data = NULL, }, 199 { .compatible = "technologic,sja1000", .data = &technologic_data, }, 200 { /* sentinel */ }, 201 }; 202 MODULE_DEVICE_TABLE(of, sp_of_table); 203 204 static int sp_probe(struct platform_device *pdev) 205 { 206 int err, irq = 0; 207 void __iomem *addr; 208 struct net_device *dev; 209 struct sja1000_priv *priv; 210 struct resource *res_mem, *res_irq = NULL; 211 struct sja1000_platform_data *pdata; 212 struct device_node *of = pdev->dev.of_node; 213 const struct of_device_id *of_id; 214 const struct sja1000_of_data *of_data = NULL; 215 size_t priv_sz = 0; 216 217 pdata = dev_get_platdata(&pdev->dev); 218 if (!pdata && !of) { 219 dev_err(&pdev->dev, "No platform data provided!\n"); 220 return -ENODEV; 221 } 222 223 res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); 224 if (!res_mem) 225 return -ENODEV; 226 227 if (!devm_request_mem_region(&pdev->dev, res_mem->start, 228 resource_size(res_mem), DRV_NAME)) 229 return -EBUSY; 230 231 addr = devm_ioremap(&pdev->dev, res_mem->start, 232 resource_size(res_mem)); 233 if (!addr) 234 return -ENOMEM; 235 236 if (of) { 237 irq = platform_get_irq(pdev, 0); 238 if (irq < 0) 239 return irq; 240 } else { 241 res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); 242 if (!res_irq) 243 return -ENODEV; 244 } 245 246 of_id = of_match_device(sp_of_table, &pdev->dev); 247 if (of_id && of_id->data) { 248 of_data = of_id->data; 249 priv_sz = of_data->priv_sz; 250 } 251 252 dev = alloc_sja1000dev(priv_sz); 253 if (!dev) 254 return -ENOMEM; 255 priv = netdev_priv(dev); 256 257 if (res_irq) { 258 irq = res_irq->start; 259 priv->irq_flags = res_irq->flags & IRQF_TRIGGER_MASK; 260 if (res_irq->flags & IORESOURCE_IRQ_SHAREABLE) 261 priv->irq_flags |= IRQF_SHARED; 262 } else { 263 priv->irq_flags = IRQF_SHARED; 264 } 265 266 dev->irq = irq; 267 priv->reg_base = addr; 268 269 if (of) { 270 sp_populate_of(priv, of); 271 272 if (of_data && of_data->init) { 273 err = of_data->init(priv, of); 274 if (err) 275 goto exit_free; 276 } 277 } else { 278 sp_populate(priv, pdata, res_mem->flags); 279 } 280 281 platform_set_drvdata(pdev, dev); 282 SET_NETDEV_DEV(dev, &pdev->dev); 283 284 err = register_sja1000dev(dev); 285 if (err) { 286 dev_err(&pdev->dev, "registering %s failed (err=%d)\n", 287 DRV_NAME, err); 288 goto exit_free; 289 } 290 291 dev_info(&pdev->dev, "%s device registered (reg_base=%p, irq=%d)\n", 292 DRV_NAME, priv->reg_base, dev->irq); 293 return 0; 294 295 exit_free: 296 free_sja1000dev(dev); 297 return err; 298 } 299 300 static int sp_remove(struct platform_device *pdev) 301 { 302 struct net_device *dev = platform_get_drvdata(pdev); 303 304 unregister_sja1000dev(dev); 305 free_sja1000dev(dev); 306 307 return 0; 308 } 309 310 static struct platform_driver sp_driver = { 311 .probe = sp_probe, 312 .remove = sp_remove, 313 .driver = { 314 .name = DRV_NAME, 315 .of_match_table = sp_of_table, 316 }, 317 }; 318 319 module_platform_driver(sp_driver); 320