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/pci.h>
17#include <linux/interrupt.h>
18#include <linux/delay.h>
19#include <linux/platform_device.h>
20#include <linux/slab.h>
21#include <linux/mfd/core.h>
22
23#include <linux/mfd/janz.h>
24
25#define DRV_NAME "janz-cmodio"
26
27/* Size of each MODULbus module in PCI BAR4 */
28#define CMODIO_MODULBUS_SIZE	0x200
29
30/* Maximum number of MODULbus modules on a CMOD-IO carrier board */
31#define CMODIO_MAX_MODULES	4
32
33/* Module Parameters */
34static unsigned int num_modules = CMODIO_MAX_MODULES;
35static char *modules[CMODIO_MAX_MODULES] = {
36	"empty", "empty", "empty", "empty",
37};
38
39module_param_array(modules, charp, &num_modules, S_IRUGO);
40MODULE_PARM_DESC(modules, "MODULbus modules attached to the carrier board");
41
42/* Unique Device Id */
43static unsigned int cmodio_id;
44
45struct cmodio_device {
46	/* Parent PCI device */
47	struct pci_dev *pdev;
48
49	/* PLX control registers */
50	struct janz_cmodio_onboard_regs __iomem *ctrl;
51
52	/* hex switch position */
53	u8 hex;
54
55	/* mfd-core API */
56	struct mfd_cell cells[CMODIO_MAX_MODULES];
57	struct resource resources[3 * CMODIO_MAX_MODULES];
58	struct janz_platform_data pdata[CMODIO_MAX_MODULES];
59};
60
61/*
62 * Subdevices using the mfd-core API
63 */
64
65static int cmodio_setup_subdevice(struct cmodio_device *priv,
66					    char *name, unsigned int devno,
67					    unsigned int modno)
68{
69	struct janz_platform_data *pdata;
70	struct mfd_cell *cell;
71	struct resource *res;
72	struct pci_dev *pci;
73
74	pci = priv->pdev;
75	cell = &priv->cells[devno];
76	res = &priv->resources[devno * 3];
77	pdata = &priv->pdata[devno];
78
79	cell->name = name;
80	cell->resources = res;
81	cell->num_resources = 3;
82
83	/* Setup the subdevice ID -- must be unique */
84	cell->id = cmodio_id++;
85
86	/* Add platform data */
87	pdata->modno = modno;
88	cell->platform_data = pdata;
89	cell->pdata_size = sizeof(*pdata);
90
91	/* MODULbus registers -- PCI BAR3 is big-endian MODULbus access */
92	res->flags = IORESOURCE_MEM;
93	res->parent = &pci->resource[3];
94	res->start = pci->resource[3].start + (CMODIO_MODULBUS_SIZE * modno);
95	res->end = res->start + CMODIO_MODULBUS_SIZE - 1;
96	res++;
97
98	/* PLX Control Registers -- PCI BAR4 is interrupt and other registers */
99	res->flags = IORESOURCE_MEM;
100	res->parent = &pci->resource[4];
101	res->start = pci->resource[4].start;
102	res->end = pci->resource[4].end;
103	res++;
104
105	/*
106	 * IRQ
107	 *
108	 * The start and end fields are used as an offset to the irq_base
109	 * parameter passed into the mfd_add_devices() function call. All
110	 * devices share the same IRQ.
111	 */
112	res->flags = IORESOURCE_IRQ;
113	res->parent = NULL;
114	res->start = 0;
115	res->end = 0;
116	res++;
117
118	return 0;
119}
120
121/* Probe each submodule using kernel parameters */
122static int cmodio_probe_submodules(struct cmodio_device *priv)
123{
124	struct pci_dev *pdev = priv->pdev;
125	unsigned int num_probed = 0;
126	char *name;
127	int i;
128
129	for (i = 0; i < num_modules; i++) {
130		name = modules[i];
131		if (!strcmp(name, "") || !strcmp(name, "empty"))
132			continue;
133
134		dev_dbg(&priv->pdev->dev, "MODULbus %d: name %s\n", i, name);
135		cmodio_setup_subdevice(priv, name, num_probed, i);
136		num_probed++;
137	}
138
139	/* print an error message if no modules were probed */
140	if (num_probed == 0) {
141		dev_err(&priv->pdev->dev, "no MODULbus modules specified, "
142					  "please set the ``modules'' kernel "
143					  "parameter according to your "
144					  "hardware configuration\n");
145		return -ENODEV;
146	}
147
148	return mfd_add_devices(&pdev->dev, 0, priv->cells,
149			       num_probed, NULL, pdev->irq, NULL);
150}
151
152/*
153 * SYSFS Attributes
154 */
155
156static ssize_t mbus_show(struct device *dev, struct device_attribute *attr,
157			 char *buf)
158{
159	struct cmodio_device *priv = dev_get_drvdata(dev);
160
161	return snprintf(buf, PAGE_SIZE, "%x\n", priv->hex);
162}
163
164static DEVICE_ATTR(modulbus_number, S_IRUGO, mbus_show, NULL);
165
166static struct attribute *cmodio_sysfs_attrs[] = {
167	&dev_attr_modulbus_number.attr,
168	NULL,
169};
170
171static const struct attribute_group cmodio_sysfs_attr_group = {
172	.attrs = cmodio_sysfs_attrs,
173};
174
175/*
176 * PCI Driver
177 */
178
179static int cmodio_pci_probe(struct pci_dev *dev,
180				      const struct pci_device_id *id)
181{
182	struct cmodio_device *priv;
183	int ret;
184
185	priv = devm_kzalloc(&dev->dev, sizeof(*priv), GFP_KERNEL);
186	if (!priv) {
187		dev_err(&dev->dev, "unable to allocate private data\n");
188		return -ENOMEM;
189	}
190
191	pci_set_drvdata(dev, priv);
192	priv->pdev = dev;
193
194	/* Hardware Initialization */
195	ret = pci_enable_device(dev);
196	if (ret) {
197		dev_err(&dev->dev, "unable to enable device\n");
198		return ret;
199	}
200
201	pci_set_master(dev);
202	ret = pci_request_regions(dev, DRV_NAME);
203	if (ret) {
204		dev_err(&dev->dev, "unable to request regions\n");
205		goto out_pci_disable_device;
206	}
207
208	/* Onboard configuration registers */
209	priv->ctrl = pci_ioremap_bar(dev, 4);
210	if (!priv->ctrl) {
211		dev_err(&dev->dev, "unable to remap onboard regs\n");
212		ret = -ENOMEM;
213		goto out_pci_release_regions;
214	}
215
216	/* Read the hex switch on the carrier board */
217	priv->hex = ioread8(&priv->ctrl->int_enable);
218
219	/* Add the MODULbus number (hex switch value) to the device's sysfs */
220	ret = sysfs_create_group(&dev->dev.kobj, &cmodio_sysfs_attr_group);
221	if (ret) {
222		dev_err(&dev->dev, "unable to create sysfs attributes\n");
223		goto out_unmap_ctrl;
224	}
225
226	/*
227	 * Disable all interrupt lines, each submodule will enable its
228	 * own interrupt line if needed
229	 */
230	iowrite8(0xf, &priv->ctrl->int_disable);
231
232	/* Register drivers for all submodules */
233	ret = cmodio_probe_submodules(priv);
234	if (ret) {
235		dev_err(&dev->dev, "unable to probe submodules\n");
236		goto out_sysfs_remove_group;
237	}
238
239	return 0;
240
241out_sysfs_remove_group:
242	sysfs_remove_group(&dev->dev.kobj, &cmodio_sysfs_attr_group);
243out_unmap_ctrl:
244	iounmap(priv->ctrl);
245out_pci_release_regions:
246	pci_release_regions(dev);
247out_pci_disable_device:
248	pci_disable_device(dev);
249
250	return ret;
251}
252
253static void cmodio_pci_remove(struct pci_dev *dev)
254{
255	struct cmodio_device *priv = pci_get_drvdata(dev);
256
257	mfd_remove_devices(&dev->dev);
258	sysfs_remove_group(&dev->dev.kobj, &cmodio_sysfs_attr_group);
259	iounmap(priv->ctrl);
260	pci_release_regions(dev);
261	pci_disable_device(dev);
262}
263
264#define PCI_VENDOR_ID_JANZ		0x13c3
265
266/* The list of devices that this module will support */
267static const struct pci_device_id cmodio_pci_ids[] = {
268	{ PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9030, PCI_VENDOR_ID_JANZ, 0x0101 },
269	{ PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9050, PCI_VENDOR_ID_JANZ, 0x0100 },
270	{ PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9030, PCI_VENDOR_ID_JANZ, 0x0201 },
271	{ PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9030, PCI_VENDOR_ID_JANZ, 0x0202 },
272	{ PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9050, PCI_VENDOR_ID_JANZ, 0x0201 },
273	{ PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9050, PCI_VENDOR_ID_JANZ, 0x0202 },
274	{ 0, }
275};
276MODULE_DEVICE_TABLE(pci, cmodio_pci_ids);
277
278static struct pci_driver cmodio_pci_driver = {
279	.name     = DRV_NAME,
280	.id_table = cmodio_pci_ids,
281	.probe    = cmodio_pci_probe,
282	.remove   = cmodio_pci_remove,
283};
284
285module_pci_driver(cmodio_pci_driver);
286
287MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>");
288MODULE_DESCRIPTION("Janz CMOD-IO PCI MODULbus Carrier Board Driver");
289MODULE_LICENSE("GPL");
290