Pileus Git - ~andy/linux/blob - drivers/net/can/c_can/c_can_platform.c

   1 /*
   2  * Platform CAN bus driver for Bosch C_CAN controller
   3  *
   4  * Copyright (C) 2010 ST Microelectronics
   5  * Bhupesh Sharma <bhupesh.sharma@st.com>
   6  *
   7  * Borrowed heavily from the C_CAN driver originally written by:
   8  * Copyright (C) 2007
   9  * - Sascha Hauer, Marc Kleine-Budde, Pengutronix <s.hauer@pengutronix.de>
  10  * - Simon Kallweit, intefo AG <simon.kallweit@intefo.ch>
  11  *
  12  * Bosch C_CAN controller is compliant to CAN protocol version 2.0 part A and B.
  13  * Bosch C_CAN user manual can be obtained from:
  14  * http://www.semiconductors.bosch.de/media/en/pdf/ipmodules_1/c_can/
  15  * users_manual_c_can.pdf
  16  *
  17  * This file is licensed under the terms of the GNU General Public
  18  * License version 2. This program is licensed "as is" without any
  19  * warranty of any kind, whether express or implied.
  20  */
  21
  22 #include <linux/kernel.h>
  23 #include <linux/module.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/delay.h>
  26 #include <linux/netdevice.h>
  27 #include <linux/if_arp.h>
  28 #include <linux/if_ether.h>
  29 #include <linux/list.h>
  30 #include <linux/io.h>
  31 #include <linux/platform_device.h>
  32 #include <linux/clk.h>
  33 #include <linux/of.h>
  34 #include <linux/of_device.h>
  35 #include <linux/pinctrl/consumer.h>
  36
  37 #include <linux/can/dev.h>
  38
  39 #include "c_can.h"
  40
  41 /*
  42  * 16-bit c_can registers can be arranged differently in the memory
  43  * architecture of different implementations. For example: 16-bit
  44  * registers can be aligned to a 16-bit boundary or 32-bit boundary etc.
  45  * Handle the same by providing a common read/write interface.
  46  */
  47 static u16 c_can_plat_read_reg_aligned_to_16bit(struct c_can_priv *priv,
  48                                                 enum reg index)
  49 {
  50         return readw(priv->base + priv->regs[index]);
  51 }
  52
  53 static void c_can_plat_write_reg_aligned_to_16bit(struct c_can_priv *priv,
  54                                                 enum reg index, u16 val)
  55 {
  56         writew(val, priv->base + priv->regs[index]);
  57 }
  58
  59 static u16 c_can_plat_read_reg_aligned_to_32bit(struct c_can_priv *priv,
  60                                                 enum reg index)
  61 {
  62         return readw(priv->base + 2 * priv->regs[index]);
  63 }
  64
  65 static void c_can_plat_write_reg_aligned_to_32bit(struct c_can_priv *priv,
  66                                                 enum reg index, u16 val)
  67 {
  68         writew(val, priv->base + 2 * priv->regs[index]);
  69 }
  70
  71 static struct platform_device_id c_can_id_table[] = {
  72         [BOSCH_C_CAN_PLATFORM] = {
  73                 .name = KBUILD_MODNAME,
  74                 .driver_data = BOSCH_C_CAN,
  75         },
  76         [BOSCH_C_CAN] = {
  77                 .name = "c_can",
  78                 .driver_data = BOSCH_C_CAN,
  79         },
  80         [BOSCH_D_CAN] = {
  81                 .name = "d_can",
  82                 .driver_data = BOSCH_D_CAN,
  83         }, {
  84         }
  85 };
  86
  87 static const struct of_device_id c_can_of_table[] = {
  88         { .compatible = "bosch,c_can", .data = &c_can_id_table[BOSCH_C_CAN] },
  89         { .compatible = "bosch,d_can", .data = &c_can_id_table[BOSCH_D_CAN] },
  90         { /* sentinel */ },
  91 };
  92
  93 static int __devinit c_can_plat_probe(struct platform_device *pdev)
  94 {
  95         int ret;
  96         void __iomem *addr;
  97         struct net_device *dev;
  98         struct c_can_priv *priv;
  99         const struct of_device_id *match;
 100         const struct platform_device_id *id;
 101         struct pinctrl *pinctrl;
 102         struct resource *mem;
 103         int irq;
 104         struct clk *clk;
 105
 106         if (pdev->dev.of_node) {
 107                 match = of_match_device(c_can_of_table, &pdev->dev);
 108                 if (!match) {
 109                         dev_err(&pdev->dev, "Failed to find matching dt id\n");
 110                         ret = -EINVAL;
 111                         goto exit;
 112                 }
 113                 id = match->data;
 114         } else {
 115                 id = platform_get_device_id(pdev);
 116         }
 117
 118         pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
 119         if (IS_ERR(pinctrl))
 120                 dev_warn(&pdev->dev,
 121                         "failed to configure pins from driver\n");
 122
 123         /* get the appropriate clk */
 124         clk = clk_get(&pdev->dev, NULL);
 125         if (IS_ERR(clk)) {
 126                 dev_err(&pdev->dev, "no clock defined\n");
 127                 ret = -ENODEV;
 128                 goto exit;
 129         }
 130
 131         /* get the platform data */
 132         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 133         irq = platform_get_irq(pdev, 0);
 134         if (!mem || irq <= 0) {
 135                 ret = -ENODEV;
 136                 goto exit_free_clk;
 137         }
 138
 139         if (!request_mem_region(mem->start, resource_size(mem),
 140                                 KBUILD_MODNAME)) {
 141                 dev_err(&pdev->dev, "resource unavailable\n");
 142                 ret = -ENODEV;
 143                 goto exit_free_clk;
 144         }
 145
 146         addr = ioremap(mem->start, resource_size(mem));
 147         if (!addr) {
 148                 dev_err(&pdev->dev, "failed to map can port\n");
 149                 ret = -ENOMEM;
 150                 goto exit_release_mem;
 151         }
 152
 153         /* allocate the c_can device */
 154         dev = alloc_c_can_dev();
 155         if (!dev) {
 156                 ret = -ENOMEM;
 157                 goto exit_iounmap;
 158         }
 159
 160         priv = netdev_priv(dev);
 161         switch (id->driver_data) {
 162         case BOSCH_C_CAN:
 163                 priv->regs = reg_map_c_can;
 164                 switch (mem->flags & IORESOURCE_MEM_TYPE_MASK) {
 165                 case IORESOURCE_MEM_32BIT:
 166                         priv->read_reg = c_can_plat_read_reg_aligned_to_32bit;
 167                         priv->write_reg = c_can_plat_write_reg_aligned_to_32bit;
 168                         break;
 169                 case IORESOURCE_MEM_16BIT:
 170                 default:
 171                         priv->read_reg = c_can_plat_read_reg_aligned_to_16bit;
 172                         priv->write_reg = c_can_plat_write_reg_aligned_to_16bit;
 173                         break;
 174                 }
 175                 break;
 176         case BOSCH_D_CAN:
 177                 priv->regs = reg_map_d_can;
 178                 priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
 179                 priv->read_reg = c_can_plat_read_reg_aligned_to_16bit;
 180                 priv->write_reg = c_can_plat_write_reg_aligned_to_16bit;
 181                 break;
 182         default:
 183                 ret = -EINVAL;
 184                 goto exit_free_device;
 185         }
 186
 187         dev->irq = irq;
 188         priv->base = addr;
 189         priv->device = &pdev->dev;
 190         priv->can.clock.freq = clk_get_rate(clk);
 191         priv->priv = clk;
 192         priv->type = id->driver_data;
 193
 194         platform_set_drvdata(pdev, dev);
 195         SET_NETDEV_DEV(dev, &pdev->dev);
 196
 197         ret = register_c_can_dev(dev);
 198         if (ret) {
 199                 dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
 200                         KBUILD_MODNAME, ret);
 201                 goto exit_free_device;
 202         }
 203
 204         dev_info(&pdev->dev, "%s device registered (regs=%p, irq=%d)\n",
 205                  KBUILD_MODNAME, priv->base, dev->irq);
 206         return 0;
 207
 208 exit_free_device:
 209         platform_set_drvdata(pdev, NULL);
 210         free_c_can_dev(dev);
 211 exit_iounmap:
 212         iounmap(addr);
 213 exit_release_mem:
 214         release_mem_region(mem->start, resource_size(mem));
 215 exit_free_clk:
 216         clk_put(clk);
 217 exit:
 218         dev_err(&pdev->dev, "probe failed\n");
 219
 220         return ret;
 221 }
 222
 223 static int __devexit c_can_plat_remove(struct platform_device *pdev)
 224 {
 225         struct net_device *dev = platform_get_drvdata(pdev);
 226         struct c_can_priv *priv = netdev_priv(dev);
 227         struct resource *mem;
 228
 229         unregister_c_can_dev(dev);
 230         platform_set_drvdata(pdev, NULL);
 231
 232         free_c_can_dev(dev);
 233         iounmap(priv->base);
 234
 235         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 236         release_mem_region(mem->start, resource_size(mem));
 237
 238         clk_put(priv->priv);
 239
 240         return 0;
 241 }
 242
 243 #ifdef CONFIG_PM
 244 static int c_can_suspend(struct platform_device *pdev, pm_message_t state)
 245 {
 246         int ret;
 247         struct net_device *ndev = platform_get_drvdata(pdev);
 248         struct c_can_priv *priv = netdev_priv(ndev);
 249
 250         if (priv->type != BOSCH_D_CAN) {
 251                 dev_warn(&pdev->dev, "Not supported\n");
 252                 return 0;
 253         }
 254
 255         if (netif_running(ndev)) {
 256                 netif_stop_queue(ndev);
 257                 netif_device_detach(ndev);
 258         }
 259
 260         ret = c_can_power_down(ndev);
 261         if (ret) {
 262                 netdev_err(ndev, "failed to enter power down mode\n");
 263                 return ret;
 264         }
 265
 266         priv->can.state = CAN_STATE_SLEEPING;
 267
 268         return 0;
 269 }
 270
 271 static int c_can_resume(struct platform_device *pdev)
 272 {
 273         int ret;
 274         struct net_device *ndev = platform_get_drvdata(pdev);
 275         struct c_can_priv *priv = netdev_priv(ndev);
 276
 277         if (priv->type != BOSCH_D_CAN) {
 278                 dev_warn(&pdev->dev, "Not supported\n");
 279                 return 0;
 280         }
 281
 282         ret = c_can_power_up(ndev);
 283         if (ret) {
 284                 netdev_err(ndev, "Still in power down mode\n");
 285                 return ret;
 286         }
 287
 288         priv->can.state = CAN_STATE_ERROR_ACTIVE;
 289
 290         if (netif_running(ndev)) {
 291                 netif_device_attach(ndev);
 292                 netif_start_queue(ndev);
 293         }
 294
 295         return 0;
 296 }
 297 #else
 298 #define c_can_suspend NULL
 299 #define c_can_resume NULL
 300 #endif
 301
 302 static struct platform_driver c_can_plat_driver = {
 303         .driver = {
 304                 .name = KBUILD_MODNAME,
 305                 .owner = THIS_MODULE,
 306                 .of_match_table = of_match_ptr(c_can_of_table),
 307         },
 308         .probe = c_can_plat_probe,
 309         .remove = __devexit_p(c_can_plat_remove),
 310         .suspend = c_can_suspend,
 311         .resume = c_can_resume,
 312         .id_table = c_can_id_table,
 313 };
 314
 315 module_platform_driver(c_can_plat_driver);
 316
 317 MODULE_AUTHOR("Bhupesh Sharma <bhupesh.sharma@st.com>");
 318 MODULE_LICENSE("GPL v2");
 319 MODULE_DESCRIPTION("Platform CAN bus driver for Bosch C_CAN controller");