1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Janz CMOD-IO MODULbus Carrier Board PCI Driver
4 *
5 * Copyright (c) 2010 Ira W. Snyder <iws@ovro.caltech.edu>
6 *
7 * Lots of inspiration and code was copied from drivers/mfd/sm501.c
8 */
9
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/pci.h>
13 #include <linux/interrupt.h>
14 #include <linux/delay.h>
15 #include <linux/platform_device.h>
16 #include <linux/slab.h>
17 #include <linux/mfd/core.h>
18
19 #include <linux/mfd/janz.h>
20
21 #define DRV_NAME "janz-cmodio"
22
23 /* Size of each MODULbus module in PCI BAR4 */
24 #define CMODIO_MODULBUS_SIZE 0x200
25
26 /* Maximum number of MODULbus modules on a CMOD-IO carrier board */
27 #define CMODIO_MAX_MODULES 4
28
29 /* Module Parameters */
30 static unsigned int num_modules = CMODIO_MAX_MODULES;
31 static char *modules[CMODIO_MAX_MODULES] = {
32 "empty", "empty", "empty", "empty",
33 };
34
35 module_param_array(modules, charp, &num_modules, S_IRUGO);
36 MODULE_PARM_DESC(modules, "MODULbus modules attached to the carrier board");
37
38 /* Unique Device Id */
39 static unsigned int cmodio_id;
40
41 struct cmodio_device {
42 /* Parent PCI device */
43 struct pci_dev *pdev;
44
45 /* PLX control registers */
46 struct janz_cmodio_onboard_regs __iomem *ctrl;
47
48 /* hex switch position */
49 u8 hex;
50
51 /* mfd-core API */
52 struct mfd_cell cells[CMODIO_MAX_MODULES];
53 struct resource resources[3 * CMODIO_MAX_MODULES];
54 struct janz_platform_data pdata[CMODIO_MAX_MODULES];
55 };
56
57 /*
58 * Subdevices using the mfd-core API
59 */
60
cmodio_setup_subdevice(struct cmodio_device * priv,char * name,unsigned int devno,unsigned int modno)61 static int cmodio_setup_subdevice(struct cmodio_device *priv,
62 char *name, unsigned int devno,
63 unsigned int modno)
64 {
65 struct janz_platform_data *pdata;
66 struct mfd_cell *cell;
67 struct resource *res;
68 struct pci_dev *pci;
69
70 pci = priv->pdev;
71 cell = &priv->cells[devno];
72 res = &priv->resources[devno * 3];
73 pdata = &priv->pdata[devno];
74
75 cell->name = name;
76 cell->resources = res;
77 cell->num_resources = 3;
78
79 /* Setup the subdevice ID -- must be unique */
80 cell->id = cmodio_id++;
81
82 /* Add platform data */
83 pdata->modno = modno;
84 cell->platform_data = pdata;
85 cell->pdata_size = sizeof(*pdata);
86
87 /* MODULbus registers -- PCI BAR3 is big-endian MODULbus access */
88 res->flags = IORESOURCE_MEM;
89 res->parent = &pci->resource[3];
90 res->start = pci->resource[3].start + (CMODIO_MODULBUS_SIZE * modno);
91 res->end = res->start + CMODIO_MODULBUS_SIZE - 1;
92 res++;
93
94 /* PLX Control Registers -- PCI BAR4 is interrupt and other registers */
95 res->flags = IORESOURCE_MEM;
96 res->parent = &pci->resource[4];
97 res->start = pci->resource[4].start;
98 res->end = pci->resource[4].end;
99 res++;
100
101 /*
102 * IRQ
103 *
104 * The start and end fields are used as an offset to the irq_base
105 * parameter passed into the mfd_add_devices() function call. All
106 * devices share the same IRQ.
107 */
108 res->flags = IORESOURCE_IRQ;
109 res->parent = NULL;
110 res->start = 0;
111 res->end = 0;
112 res++;
113
114 return 0;
115 }
116
117 /* Probe each submodule using kernel parameters */
cmodio_probe_submodules(struct cmodio_device * priv)118 static int cmodio_probe_submodules(struct cmodio_device *priv)
119 {
120 struct pci_dev *pdev = priv->pdev;
121 unsigned int num_probed = 0;
122 char *name;
123 int i;
124
125 for (i = 0; i < num_modules; i++) {
126 name = modules[i];
127 if (!strcmp(name, "") || !strcmp(name, "empty"))
128 continue;
129
130 dev_dbg(&priv->pdev->dev, "MODULbus %d: name %s\n", i, name);
131 cmodio_setup_subdevice(priv, name, num_probed, i);
132 num_probed++;
133 }
134
135 /* print an error message if no modules were probed */
136 if (num_probed == 0) {
137 dev_err(&priv->pdev->dev, "no MODULbus modules specified, "
138 "please set the ``modules'' kernel "
139 "parameter according to your "
140 "hardware configuration\n");
141 return -ENODEV;
142 }
143
144 return mfd_add_devices(&pdev->dev, 0, priv->cells,
145 num_probed, NULL, pdev->irq, NULL);
146 }
147
148 /*
149 * SYSFS Attributes
150 */
151
mbus_show(struct device * dev,struct device_attribute * attr,char * buf)152 static ssize_t mbus_show(struct device *dev, struct device_attribute *attr,
153 char *buf)
154 {
155 struct cmodio_device *priv = dev_get_drvdata(dev);
156
157 return snprintf(buf, PAGE_SIZE, "%x\n", priv->hex);
158 }
159
160 static DEVICE_ATTR(modulbus_number, S_IRUGO, mbus_show, NULL);
161
162 static struct attribute *cmodio_sysfs_attrs[] = {
163 &dev_attr_modulbus_number.attr,
164 NULL,
165 };
166
167 static const struct attribute_group cmodio_sysfs_attr_group = {
168 .attrs = cmodio_sysfs_attrs,
169 };
170
171 /*
172 * PCI Driver
173 */
174
cmodio_pci_probe(struct pci_dev * dev,const struct pci_device_id * id)175 static int cmodio_pci_probe(struct pci_dev *dev,
176 const struct pci_device_id *id)
177 {
178 struct cmodio_device *priv;
179 int ret;
180
181 priv = devm_kzalloc(&dev->dev, sizeof(*priv), GFP_KERNEL);
182 if (!priv)
183 return -ENOMEM;
184
185 pci_set_drvdata(dev, priv);
186 priv->pdev = dev;
187
188 /* Hardware Initialization */
189 ret = pci_enable_device(dev);
190 if (ret) {
191 dev_err(&dev->dev, "unable to enable device\n");
192 return ret;
193 }
194
195 pci_set_master(dev);
196 ret = pci_request_regions(dev, DRV_NAME);
197 if (ret) {
198 dev_err(&dev->dev, "unable to request regions\n");
199 goto out_pci_disable_device;
200 }
201
202 /* Onboard configuration registers */
203 priv->ctrl = pci_ioremap_bar(dev, 4);
204 if (!priv->ctrl) {
205 dev_err(&dev->dev, "unable to remap onboard regs\n");
206 ret = -ENOMEM;
207 goto out_pci_release_regions;
208 }
209
210 /* Read the hex switch on the carrier board */
211 priv->hex = ioread8(&priv->ctrl->int_enable);
212
213 /* Add the MODULbus number (hex switch value) to the device's sysfs */
214 ret = sysfs_create_group(&dev->dev.kobj, &cmodio_sysfs_attr_group);
215 if (ret) {
216 dev_err(&dev->dev, "unable to create sysfs attributes\n");
217 goto out_unmap_ctrl;
218 }
219
220 /*
221 * Disable all interrupt lines, each submodule will enable its
222 * own interrupt line if needed
223 */
224 iowrite8(0xf, &priv->ctrl->int_disable);
225
226 /* Register drivers for all submodules */
227 ret = cmodio_probe_submodules(priv);
228 if (ret) {
229 dev_err(&dev->dev, "unable to probe submodules\n");
230 goto out_sysfs_remove_group;
231 }
232
233 return 0;
234
235 out_sysfs_remove_group:
236 sysfs_remove_group(&dev->dev.kobj, &cmodio_sysfs_attr_group);
237 out_unmap_ctrl:
238 iounmap(priv->ctrl);
239 out_pci_release_regions:
240 pci_release_regions(dev);
241 out_pci_disable_device:
242 pci_disable_device(dev);
243
244 return ret;
245 }
246
cmodio_pci_remove(struct pci_dev * dev)247 static void cmodio_pci_remove(struct pci_dev *dev)
248 {
249 struct cmodio_device *priv = pci_get_drvdata(dev);
250
251 mfd_remove_devices(&dev->dev);
252 sysfs_remove_group(&dev->dev.kobj, &cmodio_sysfs_attr_group);
253 iounmap(priv->ctrl);
254 pci_release_regions(dev);
255 pci_disable_device(dev);
256 }
257
258 #define PCI_VENDOR_ID_JANZ 0x13c3
259
260 /* The list of devices that this module will support */
261 static const struct pci_device_id cmodio_pci_ids[] = {
262 { PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9030, PCI_VENDOR_ID_JANZ, 0x0101 },
263 { PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9050, PCI_VENDOR_ID_JANZ, 0x0100 },
264 { PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9030, PCI_VENDOR_ID_JANZ, 0x0201 },
265 { PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9030, PCI_VENDOR_ID_JANZ, 0x0202 },
266 { PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9050, PCI_VENDOR_ID_JANZ, 0x0201 },
267 { PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9050, PCI_VENDOR_ID_JANZ, 0x0202 },
268 { 0, }
269 };
270 MODULE_DEVICE_TABLE(pci, cmodio_pci_ids);
271
272 static struct pci_driver cmodio_pci_driver = {
273 .name = DRV_NAME,
274 .id_table = cmodio_pci_ids,
275 .probe = cmodio_pci_probe,
276 .remove = cmodio_pci_remove,
277 };
278
279 module_pci_driver(cmodio_pci_driver);
280
281 MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>");
282 MODULE_DESCRIPTION("Janz CMOD-IO PCI MODULbus Carrier Board Driver");
283 MODULE_LICENSE("GPL");
284