drivers/mfd/janz-cmodio.c

   1 /*
   2  * Janz CMOD-IO MODULbus Carrier Board PCI Driver
   3  *
   4  * Copyright (c) 2010 Ira W. Snyder <iws@ovro.caltech.edu>
   5  *
   6  * Lots of inspiration and code was copied from drivers/mfd/sm501.c
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by the
  10  * Free Software Foundation; either version 2 of the License, or (at your
  11  * option) any later version.
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/module.h>
  16 #include <linux/init.h>
  17 #include <linux/pci.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/delay.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/slab.h>
  22 #include <linux/mfd/core.h>
  23
  24 #include <linux/mfd/janz.h>
  25
  26 #define DRV_NAME "janz-cmodio"
  27
  28 /* Size of each MODULbus module in PCI BAR4 */
  29 #define CMODIO_MODULBUS_SIZE    0x200
  30
  31 /* Maximum number of MODULbus modules on a CMOD-IO carrier board */
  32 #define CMODIO_MAX_MODULES      4
  33
  34 /* Module Parameters */
  35 static unsigned int num_modules = CMODIO_MAX_MODULES;
  36 static char *modules[CMODIO_MAX_MODULES] = {
  37         "empty", "empty", "empty", "empty",
  38 };
  39
  40 module_param_array(modules, charp, &num_modules, S_IRUGO);
  41 MODULE_PARM_DESC(modules, "MODULbus modules attached to the carrier board");
  42
  43 /* Unique Device Id */
  44 static unsigned int cmodio_id;
  45
  46 struct cmodio_device {
  47         /* Parent PCI device */
  48         struct pci_dev *pdev;
  49
  50         /* PLX control registers */
  51         struct janz_cmodio_onboard_regs __iomem *ctrl;
  52
  53         /* hex switch position */
  54         u8 hex;
  55
  56         /* mfd-core API */
  57         struct mfd_cell cells[CMODIO_MAX_MODULES];
  58         struct resource resources[3 * CMODIO_MAX_MODULES];
  59         struct janz_platform_data pdata[CMODIO_MAX_MODULES];
  60 };
  61
  62 /*
  63  * Subdevices using the mfd-core API
  64  */
  65
  66 static int cmodio_setup_subdevice(struct cmodio_device *priv,
  67                                             char *name, unsigned int devno,
  68                                             unsigned int modno)
  69 {
  70         struct janz_platform_data *pdata;
  71         struct mfd_cell *cell;
  72         struct resource *res;
  73         struct pci_dev *pci;
  74
  75         pci = priv->pdev;
  76         cell = &priv->cells[devno];
  77         res = &priv->resources[devno * 3];
  78         pdata = &priv->pdata[devno];
  79
  80         cell->name = name;
  81         cell->resources = res;
  82         cell->num_resources = 3;
  83
  84         /* Setup the subdevice ID -- must be unique */
  85         cell->id = cmodio_id++;
  86
  87         /* Add platform data */
  88         pdata->modno = modno;
  89         cell->platform_data = pdata;
  90         cell->pdata_size = sizeof(*pdata);
  91
  92         /* MODULbus registers -- PCI BAR3 is big-endian MODULbus access */
  93         res->flags = IORESOURCE_MEM;
  94         res->parent = &pci->resource[3];
  95         res->start = pci->resource[3].start + (CMODIO_MODULBUS_SIZE * modno);
  96         res->end = res->start + CMODIO_MODULBUS_SIZE - 1;
  97         res++;
  98
  99         /* PLX Control Registers -- PCI BAR4 is interrupt and other registers */
 100         res->flags = IORESOURCE_MEM;
 101         res->parent = &pci->resource[4];
 102         res->start = pci->resource[4].start;
 103         res->end = pci->resource[4].end;
 104         res++;
 105
 106         /*
 107          * IRQ
 108          *
 109          * The start and end fields are used as an offset to the irq_base
 110          * parameter passed into the mfd_add_devices() function call. All
 111          * devices share the same IRQ.
 112          */
 113         res->flags = IORESOURCE_IRQ;
 114         res->parent = NULL;
 115         res->start = 0;
 116         res->end = 0;
 117         res++;
 118
 119         return 0;
 120 }
 121
 122 /* Probe each submodule using kernel parameters */
 123 static int cmodio_probe_submodules(struct cmodio_device *priv)
 124 {
 125         struct pci_dev *pdev = priv->pdev;
 126         unsigned int num_probed = 0;
 127         char *name;
 128         int i;
 129
 130         for (i = 0; i < num_modules; i++) {
 131                 name = modules[i];
 132                 if (!strcmp(name, "") || !strcmp(name, "empty"))
 133                         continue;
 134
 135                 dev_dbg(&priv->pdev->dev, "MODULbus %d: name %s\n", i, name);
 136                 cmodio_setup_subdevice(priv, name, num_probed, i);
 137                 num_probed++;
 138         }
 139
 140         /* print an error message if no modules were probed */
 141         if (num_probed == 0) {
 142                 dev_err(&priv->pdev->dev, "no MODULbus modules specified, "
 143                                           "please set the ``modules'' kernel "
 144                                           "parameter according to your "
 145                                           "hardware configuration\n");
 146                 return -ENODEV;
 147         }
 148
 149         return mfd_add_devices(&pdev->dev, 0, priv->cells,
 150                                num_probed, NULL, pdev->irq, NULL);
 151 }
 152
 153 /*
 154  * SYSFS Attributes
 155  */
 156
 157 static ssize_t mbus_show(struct device *dev, struct device_attribute *attr,
 158                          char *buf)
 159 {
 160         struct cmodio_device *priv = dev_get_drvdata(dev);
 161
 162         return snprintf(buf, PAGE_SIZE, "%x\n", priv->hex);
 163 }
 164
 165 static DEVICE_ATTR(modulbus_number, S_IRUGO, mbus_show, NULL);
 166
 167 static struct attribute *cmodio_sysfs_attrs[] = {
 168         &dev_attr_modulbus_number.attr,
 169         NULL,
 170 };
 171
 172 static const struct attribute_group cmodio_sysfs_attr_group = {
 173         .attrs = cmodio_sysfs_attrs,
 174 };
 175
 176 /*
 177  * PCI Driver
 178  */
 179
 180 static int cmodio_pci_probe(struct pci_dev *dev,
 181                                       const struct pci_device_id *id)
 182 {
 183         struct cmodio_device *priv;
 184         int ret;
 185
 186         priv = devm_kzalloc(&dev->dev, sizeof(*priv), GFP_KERNEL);
 187         if (!priv) {
 188                 dev_err(&dev->dev, "unable to allocate private data\n");
 189                 return -ENOMEM;
 190         }
 191
 192         pci_set_drvdata(dev, priv);
 193         priv->pdev = dev;
 194
 195         /* Hardware Initialization */
 196         ret = pci_enable_device(dev);
 197         if (ret) {
 198                 dev_err(&dev->dev, "unable to enable device\n");
 199                 return ret;
 200         }
 201
 202         pci_set_master(dev);
 203         ret = pci_request_regions(dev, DRV_NAME);
 204         if (ret) {
 205                 dev_err(&dev->dev, "unable to request regions\n");
 206                 goto out_pci_disable_device;
 207         }
 208
 209         /* Onboard configuration registers */
 210         priv->ctrl = pci_ioremap_bar(dev, 4);
 211         if (!priv->ctrl) {
 212                 dev_err(&dev->dev, "unable to remap onboard regs\n");
 213                 ret = -ENOMEM;
 214                 goto out_pci_release_regions;
 215         }
 216
 217         /* Read the hex switch on the carrier board */
 218         priv->hex = ioread8(&priv->ctrl->int_enable);
 219
 220         /* Add the MODULbus number (hex switch value) to the device's sysfs */
 221         ret = sysfs_create_group(&dev->dev.kobj, &cmodio_sysfs_attr_group);
 222         if (ret) {
 223                 dev_err(&dev->dev, "unable to create sysfs attributes\n");
 224                 goto out_unmap_ctrl;
 225         }
 226
 227         /*
 228          * Disable all interrupt lines, each submodule will enable its
 229          * own interrupt line if needed
 230          */
 231         iowrite8(0xf, &priv->ctrl->int_disable);
 232
 233         /* Register drivers for all submodules */
 234         ret = cmodio_probe_submodules(priv);
 235         if (ret) {
 236                 dev_err(&dev->dev, "unable to probe submodules\n");
 237                 goto out_sysfs_remove_group;
 238         }
 239
 240         return 0;
 241
 242 out_sysfs_remove_group:
 243         sysfs_remove_group(&dev->dev.kobj, &cmodio_sysfs_attr_group);
 244 out_unmap_ctrl:
 245         iounmap(priv->ctrl);
 246 out_pci_release_regions:
 247         pci_release_regions(dev);
 248 out_pci_disable_device:
 249         pci_disable_device(dev);
 250
 251         return ret;
 252 }
 253
 254 static void cmodio_pci_remove(struct pci_dev *dev)
 255 {
 256         struct cmodio_device *priv = pci_get_drvdata(dev);
 257
 258         mfd_remove_devices(&dev->dev);
 259         sysfs_remove_group(&dev->dev.kobj, &cmodio_sysfs_attr_group);
 260         iounmap(priv->ctrl);
 261         pci_release_regions(dev);
 262         pci_disable_device(dev);
 263 }
 264
 265 #define PCI_VENDOR_ID_JANZ              0x13c3
 266
 267 /* The list of devices that this module will support */
 268 static DEFINE_PCI_DEVICE_TABLE(cmodio_pci_ids) = {
 269         { PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9030, PCI_VENDOR_ID_JANZ, 0x0101 },
 270         { PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9050, PCI_VENDOR_ID_JANZ, 0x0100 },
 271         { 0, }
 272 };
 273 MODULE_DEVICE_TABLE(pci, cmodio_pci_ids);
 274
 275 static struct pci_driver cmodio_pci_driver = {
 276         .name     = DRV_NAME,
 277         .id_table = cmodio_pci_ids,
 278         .probe    = cmodio_pci_probe,
 279         .remove   = cmodio_pci_remove,
 280 };
 281
 282 module_pci_driver(cmodio_pci_driver);
 283
 284 MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>");
 285 MODULE_DESCRIPTION("Janz CMOD-IO PCI MODULbus Carrier Board Driver");
 286 MODULE_LICENSE("GPL");