drivers/net/can/sja1000/sja1000_platform.c

   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);