ibmebus.c

  1/*
  2 * IBM PowerPC IBM eBus Infrastructure Support.
  3 *
  4 * Copyright (c) 2005 IBM Corporation
  5 *  Joachim Fenkes <fenkes@de.ibm.com>
  6 *  Heiko J Schick <schickhj@de.ibm.com>
  7 *
  8 * All rights reserved.
  9 *
 10 * This source code is distributed under a dual license of GPL v2.0 and OpenIB
 11 * BSD.
 12 *
 13 * OpenIB BSD License
 14 *
 15 * Redistribution and use in source and binary forms, with or without
 16 * modification, are permitted provided that the following conditions are met:
 17 *
 18 * Redistributions of source code must retain the above copyright notice, this
 19 * list of conditions and the following disclaimer.
 20 *
 21 * Redistributions in binary form must reproduce the above copyright notice,
 22 * this list of conditions and the following disclaimer in the documentation
 23 * and/or other materials
 24 * provided with the distribution.
 25 *
 26 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 27 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 30 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 33 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
 34 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 36 * POSSIBILITY OF SUCH DAMAGE.
 37 */
 38
 39#include <linux/init.h>
 40#include <linux/export.h>
 41#include <linux/console.h>
 42#include <linux/kobject.h>
 43#include <linux/dma-map-ops.h>
 44#include <linux/interrupt.h>
 45#include <linux/irqdomain.h>
 46#include <linux/of.h>
 47#include <linux/slab.h>
 48#include <linux/stat.h>
 49#include <linux/of_platform.h>
 50#include <linux/platform_device.h>
 51#include <asm/ibmebus.h>
 52#include <asm/machdep.h>
 53
 54static struct device ibmebus_bus_device = { /* fake "parent" device */
 55	.init_name = "ibmebus",
 56};
 57
 58const struct bus_type ibmebus_bus_type;
 59
 60/* These devices will automatically be added to the bus during init */
 61static const struct of_device_id ibmebus_matches[] __initconst = {
 62	{ .compatible = "IBM,lhca" },
 63	{ .compatible = "IBM,lhea" },
 64	{},
 65};
 66
 67static void *ibmebus_alloc_coherent(struct device *dev,
 68				    size_t size,
 69				    dma_addr_t *dma_handle,
 70				    gfp_t flag,
 71				    unsigned long attrs)
 72{
 73	void *mem;
 74
 75	mem = kmalloc(size, flag);
 76	*dma_handle = (dma_addr_t)mem;
 77
 78	return mem;
 79}
 80
 81static void ibmebus_free_coherent(struct device *dev,
 82				  size_t size, void *vaddr,
 83				  dma_addr_t dma_handle,
 84				  unsigned long attrs)
 85{
 86	kfree(vaddr);
 87}
 88
 89static dma_addr_t ibmebus_map_phys(struct device *dev, phys_addr_t phys,
 90				   size_t size,
 91				   enum dma_data_direction direction,
 92				   unsigned long attrs)
 93{
 94	if (attrs & DMA_ATTR_MMIO)
 95		return DMA_MAPPING_ERROR;
 96
 97	return (dma_addr_t)(phys_to_virt(phys));
 98}
 99
100static void ibmebus_unmap_phys(struct device *dev,
101			       dma_addr_t dma_addr,
102			       size_t size,
103			       enum dma_data_direction direction,
104			       unsigned long attrs)
105{
106	return;
107}
108
109static int ibmebus_map_sg(struct device *dev,
110			  struct scatterlist *sgl,
111			  int nents, enum dma_data_direction direction,
112			  unsigned long attrs)
113{
114	struct scatterlist *sg;
115	int i;
116
117	for_each_sg(sgl, sg, nents, i) {
118		sg->dma_address = (dma_addr_t) sg_virt(sg);
119		sg->dma_length = sg->length;
120	}
121
122	return nents;
123}
124
125static void ibmebus_unmap_sg(struct device *dev,
126			     struct scatterlist *sg,
127			     int nents, enum dma_data_direction direction,
128			     unsigned long attrs)
129{
130	return;
131}
132
133static int ibmebus_dma_supported(struct device *dev, u64 mask)
134{
135	return mask == DMA_BIT_MASK(64);
136}
137
138static u64 ibmebus_dma_get_required_mask(struct device *dev)
139{
140	return DMA_BIT_MASK(64);
141}
142
143static const struct dma_map_ops ibmebus_dma_ops = {
144	.alloc              = ibmebus_alloc_coherent,
145	.free               = ibmebus_free_coherent,
146	.map_sg             = ibmebus_map_sg,
147	.unmap_sg           = ibmebus_unmap_sg,
148	.dma_supported      = ibmebus_dma_supported,
149	.get_required_mask  = ibmebus_dma_get_required_mask,
150	.map_phys           = ibmebus_map_phys,
151	.unmap_phys         = ibmebus_unmap_phys,
152};
153
154static int ibmebus_match_path(struct device *dev, const void *data)
155{
156	struct device_node *dn = to_platform_device(dev)->dev.of_node;
157	struct device_node *tn = of_find_node_by_path(data);
158
159	of_node_put(tn);
160
161	return (tn == dn);
162}
163
164static int ibmebus_match_node(struct device *dev, const void *data)
165{
166	return to_platform_device(dev)->dev.of_node == data;
167}
168
169static int ibmebus_create_device(struct device_node *dn)
170{
171	struct platform_device *dev;
172	int ret;
173
174	dev = of_device_alloc(dn, NULL, &ibmebus_bus_device);
175	if (!dev)
176		return -ENOMEM;
177
178	dev->dev.bus = &ibmebus_bus_type;
179	dev->dev.dma_ops = &ibmebus_dma_ops;
180
181	ret = of_device_add(dev);
182	if (ret)
183		platform_device_put(dev);
184	return ret;
185}
186
187static int ibmebus_create_devices(const struct of_device_id *matches)
188{
189	struct device_node *root, *child;
190	struct device *dev;
191	int ret = 0;
192
193	root = of_find_node_by_path("/");
194
195	for_each_child_of_node(root, child) {
196		if (!of_match_node(matches, child))
197			continue;
198
199		dev = bus_find_device(&ibmebus_bus_type, NULL, child,
200				      ibmebus_match_node);
201		if (dev) {
202			put_device(dev);
203			continue;
204		}
205
206		ret = ibmebus_create_device(child);
207		if (ret) {
208			printk(KERN_ERR "%s: failed to create device (%i)",
209			       __func__, ret);
210			of_node_put(child);
211			break;
212		}
213	}
214
215	of_node_put(root);
216	return ret;
217}
218
219int ibmebus_register_driver(struct platform_driver *drv)
220{
221	/* If the driver uses devices that ibmebus doesn't know, add them */
222	ibmebus_create_devices(drv->driver.of_match_table);
223
224	drv->driver.bus = &ibmebus_bus_type;
225	return driver_register(&drv->driver);
226}
227EXPORT_SYMBOL(ibmebus_register_driver);
228
229void ibmebus_unregister_driver(struct platform_driver *drv)
230{
231	driver_unregister(&drv->driver);
232}
233EXPORT_SYMBOL(ibmebus_unregister_driver);
234
235int ibmebus_request_irq(u32 ist, irq_handler_t handler,
236			unsigned long irq_flags, const char *devname,
237			void *dev_id)
238{
239	unsigned int irq = irq_create_mapping(NULL, ist);
240
241	if (!irq)
242		return -EINVAL;
243
244	return request_irq(irq, handler, irq_flags, devname, dev_id);
245}
246EXPORT_SYMBOL(ibmebus_request_irq);
247
248void ibmebus_free_irq(u32 ist, void *dev_id)
249{
250	unsigned int irq = irq_find_mapping(NULL, ist);
251
252	free_irq(irq, dev_id);
253	irq_dispose_mapping(irq);
254}
255EXPORT_SYMBOL(ibmebus_free_irq);
256
257static char *ibmebus_chomp(const char *in, size_t count)
258{
259	char *out = kmalloc(count + 1, GFP_KERNEL);
260
261	if (!out)
262		return NULL;
263
264	memcpy(out, in, count);
265	out[count] = '\0';
266	if (out[count - 1] == '\n')
267		out[count - 1] = '\0';
268
269	return out;
270}
271
272static ssize_t probe_store(const struct bus_type *bus, const char *buf, size_t count)
273{
274	struct device_node *dn = NULL;
275	struct device *dev;
276	char *path;
277	ssize_t rc = 0;
278
279	path = ibmebus_chomp(buf, count);
280	if (!path)
281		return -ENOMEM;
282
283	dev = bus_find_device(&ibmebus_bus_type, NULL, path,
284			      ibmebus_match_path);
285	if (dev) {
286		put_device(dev);
287		printk(KERN_WARNING "%s: %s has already been probed\n",
288		       __func__, path);
289		rc = -EEXIST;
290		goto out;
291	}
292
293	if ((dn = of_find_node_by_path(path))) {
294		rc = ibmebus_create_device(dn);
295		of_node_put(dn);
296	} else {
297		printk(KERN_WARNING "%s: no such device node: %s\n",
298		       __func__, path);
299		rc = -ENODEV;
300	}
301
302out:
303	kfree(path);
304	if (rc)
305		return rc;
306	return count;
307}
308static BUS_ATTR_WO(probe);
309
310static ssize_t remove_store(const struct bus_type *bus, const char *buf, size_t count)
311{
312	struct device *dev;
313	char *path;
314
315	path = ibmebus_chomp(buf, count);
316	if (!path)
317		return -ENOMEM;
318
319	if ((dev = bus_find_device(&ibmebus_bus_type, NULL, path,
320				   ibmebus_match_path))) {
321		of_device_unregister(to_platform_device(dev));
322		put_device(dev);
323
324		kfree(path);
325		return count;
326	} else {
327		printk(KERN_WARNING "%s: %s not on the bus\n",
328		       __func__, path);
329
330		kfree(path);
331		return -ENODEV;
332	}
333}
334static BUS_ATTR_WO(remove);
335
336static struct attribute *ibmbus_bus_attrs[] = {
337	&bus_attr_probe.attr,
338	&bus_attr_remove.attr,
339	NULL,
340};
341ATTRIBUTE_GROUPS(ibmbus_bus);
342
343static int ibmebus_bus_bus_match(struct device *dev, const struct device_driver *drv)
344{
345	const struct of_device_id *matches = drv->of_match_table;
346
347	if (!matches)
348		return 0;
349
350	return of_match_device(matches, dev) != NULL;
351}
352
353static int ibmebus_bus_device_probe(struct device *dev)
354{
355	int error = -ENODEV;
356	struct platform_driver *drv;
357	struct platform_device *of_dev;
358
359	drv = to_platform_driver(dev->driver);
360	of_dev = to_platform_device(dev);
361
362	if (!drv->probe)
363		return error;
364
365	get_device(dev);
366
367	if (of_driver_match_device(dev, dev->driver))
368		error = drv->probe(of_dev);
369	if (error)
370		put_device(dev);
371
372	return error;
373}
374
375static void ibmebus_bus_device_remove(struct device *dev)
376{
377	struct platform_device *of_dev = to_platform_device(dev);
378	struct platform_driver *drv = to_platform_driver(dev->driver);
379
380	if (dev->driver && drv->remove)
381		drv->remove(of_dev);
382}
383
384static void ibmebus_bus_device_shutdown(struct device *dev)
385{
386	struct platform_device *of_dev = to_platform_device(dev);
387	struct platform_driver *drv = to_platform_driver(dev->driver);
388
389	if (dev->driver && drv->shutdown)
390		drv->shutdown(of_dev);
391}
392
393/*
394 * ibmebus_bus_device_attrs
395 */
396static ssize_t devspec_show(struct device *dev,
397				struct device_attribute *attr, char *buf)
398{
399	struct platform_device *ofdev;
400
401	ofdev = to_platform_device(dev);
402	return sprintf(buf, "%pOF\n", ofdev->dev.of_node);
403}
404static DEVICE_ATTR_RO(devspec);
405
406static ssize_t name_show(struct device *dev,
407				struct device_attribute *attr, char *buf)
408{
409	struct platform_device *ofdev;
410
411	ofdev = to_platform_device(dev);
412	return sprintf(buf, "%pOFn\n", ofdev->dev.of_node);
413}
414static DEVICE_ATTR_RO(name);
415
416static ssize_t modalias_show(struct device *dev,
417				struct device_attribute *attr, char *buf)
418{
419	return of_device_modalias(dev, buf, PAGE_SIZE);
420}
421static DEVICE_ATTR_RO(modalias);
422
423static struct attribute *ibmebus_bus_device_attrs[] = {
424	&dev_attr_devspec.attr,
425	&dev_attr_name.attr,
426	&dev_attr_modalias.attr,
427	NULL,
428};
429ATTRIBUTE_GROUPS(ibmebus_bus_device);
430
431static int ibmebus_bus_modalias(const struct device *dev, struct kobj_uevent_env *env)
432{
433	return of_device_uevent_modalias(dev, env);
434}
435
436const struct bus_type ibmebus_bus_type = {
437	.name      = "ibmebus",
438	.uevent    = ibmebus_bus_modalias,
439	.bus_groups = ibmbus_bus_groups,
440	.match     = ibmebus_bus_bus_match,
441	.probe     = ibmebus_bus_device_probe,
442	.remove    = ibmebus_bus_device_remove,
443	.shutdown  = ibmebus_bus_device_shutdown,
444	.dev_groups = ibmebus_bus_device_groups,
445};
446EXPORT_SYMBOL(ibmebus_bus_type);
447
448static int __init ibmebus_bus_init(void)
449{
450	int err;
451
452	printk(KERN_INFO "IBM eBus Device Driver\n");
453
454	err = bus_register(&ibmebus_bus_type);
455	if (err) {
456		printk(KERN_ERR "%s: failed to register IBM eBus.\n",
457		       __func__);
458		return err;
459	}
460
461	err = device_register(&ibmebus_bus_device);
462	if (err) {
463		printk(KERN_WARNING "%s: device_register returned %i\n",
464		       __func__, err);
465		put_device(&ibmebus_bus_device);
466		bus_unregister(&ibmebus_bus_type);
467
468		return err;
469	}
470
471	err = ibmebus_create_devices(ibmebus_matches);
472	if (err) {
473		device_unregister(&ibmebus_bus_device);
474		bus_unregister(&ibmebus_bus_type);
475		return err;
476	}
477
478	return 0;
479}
480machine_postcore_initcall(pseries, ibmebus_bus_init);