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Diffstat (limited to 'drivers/spi/spi.c')
-rw-r--r--drivers/spi/spi.c118
1 files changed, 86 insertions, 32 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 7cd356b17644..2ecb86cb3689 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -26,13 +26,9 @@
26#include <linux/spi/spi.h> 26#include <linux/spi/spi.h>
27 27
28 28
29/* SPI bustype and spi_master class are registered during early boot, 29/* SPI bustype and spi_master class are registered after board init code
30 * usually before board init code provides the SPI device tables, and 30 * provides the SPI device tables, ensuring that both are present by the
31 * are available later when driver init code needs them. 31 * time controller driver registration causes spi_devices to "enumerate".
32 *
33 * Drivers for SPI devices started out like those for platform bus
34 * devices. But both have changed in 2.6.15; maybe this should get
35 * an "spi_driver" structure at some point (not currently needed)
36 */ 32 */
37static void spidev_release(struct device *dev) 33static void spidev_release(struct device *dev)
38{ 34{
@@ -83,10 +79,7 @@ static int spi_uevent(struct device *dev, char **envp, int num_envp,
83 79
84#ifdef CONFIG_PM 80#ifdef CONFIG_PM
85 81
86/* Suspend/resume in "struct device_driver" don't really need that 82/*
87 * strange third parameter, so we just make it a constant and expect
88 * SPI drivers to ignore it just like most platform drivers do.
89 *
90 * NOTE: the suspend() method for an spi_master controller driver 83 * NOTE: the suspend() method for an spi_master controller driver
91 * should verify that all its child devices are marked as suspended; 84 * should verify that all its child devices are marked as suspended;
92 * suspend requests delivered through sysfs power/state files don't 85 * suspend requests delivered through sysfs power/state files don't
@@ -94,13 +87,14 @@ static int spi_uevent(struct device *dev, char **envp, int num_envp,
94 */ 87 */
95static int spi_suspend(struct device *dev, pm_message_t message) 88static int spi_suspend(struct device *dev, pm_message_t message)
96{ 89{
97 int value; 90 int value;
91 struct spi_driver *drv = to_spi_driver(dev->driver);
98 92
99 if (!dev->driver || !dev->driver->suspend) 93 if (!drv || !drv->suspend)
100 return 0; 94 return 0;
101 95
102 /* suspend will stop irqs and dma; no more i/o */ 96 /* suspend will stop irqs and dma; no more i/o */
103 value = dev->driver->suspend(dev, message); 97 value = drv->suspend(to_spi_device(dev), message);
104 if (value == 0) 98 if (value == 0)
105 dev->power.power_state = message; 99 dev->power.power_state = message;
106 return value; 100 return value;
@@ -108,13 +102,14 @@ static int spi_suspend(struct device *dev, pm_message_t message)
108 102
109static int spi_resume(struct device *dev) 103static int spi_resume(struct device *dev)
110{ 104{
111 int value; 105 int value;
106 struct spi_driver *drv = to_spi_driver(dev->driver);
112 107
113 if (!dev->driver || !dev->driver->resume) 108 if (!drv || !drv->resume)
114 return 0; 109 return 0;
115 110
116 /* resume may restart the i/o queue */ 111 /* resume may restart the i/o queue */
117 value = dev->driver->resume(dev); 112 value = drv->resume(to_spi_device(dev));
118 if (value == 0) 113 if (value == 0)
119 dev->power.power_state = PMSG_ON; 114 dev->power.power_state = PMSG_ON;
120 return value; 115 return value;
@@ -135,6 +130,41 @@ struct bus_type spi_bus_type = {
135}; 130};
136EXPORT_SYMBOL_GPL(spi_bus_type); 131EXPORT_SYMBOL_GPL(spi_bus_type);
137 132
133
134static int spi_drv_probe(struct device *dev)
135{
136 const struct spi_driver *sdrv = to_spi_driver(dev->driver);
137
138 return sdrv->probe(to_spi_device(dev));
139}
140
141static int spi_drv_remove(struct device *dev)
142{
143 const struct spi_driver *sdrv = to_spi_driver(dev->driver);
144
145 return sdrv->remove(to_spi_device(dev));
146}
147
148static void spi_drv_shutdown(struct device *dev)
149{
150 const struct spi_driver *sdrv = to_spi_driver(dev->driver);
151
152 sdrv->shutdown(to_spi_device(dev));
153}
154
155int spi_register_driver(struct spi_driver *sdrv)
156{
157 sdrv->driver.bus = &spi_bus_type;
158 if (sdrv->probe)
159 sdrv->driver.probe = spi_drv_probe;
160 if (sdrv->remove)
161 sdrv->driver.remove = spi_drv_remove;
162 if (sdrv->shutdown)
163 sdrv->driver.shutdown = spi_drv_shutdown;
164 return driver_register(&sdrv->driver);
165}
166EXPORT_SYMBOL_GPL(spi_register_driver);
167
138/*-------------------------------------------------------------------------*/ 168/*-------------------------------------------------------------------------*/
139 169
140/* SPI devices should normally not be created by SPI device drivers; that 170/* SPI devices should normally not be created by SPI device drivers; that
@@ -208,13 +238,15 @@ spi_new_device(struct spi_master *master, struct spi_board_info *chip)
208 if (status < 0) { 238 if (status < 0) {
209 dev_dbg(dev, "can't %s %s, status %d\n", 239 dev_dbg(dev, "can't %s %s, status %d\n",
210 "add", proxy->dev.bus_id, status); 240 "add", proxy->dev.bus_id, status);
211fail: 241 goto fail;
212 class_device_put(&master->cdev);
213 kfree(proxy);
214 return NULL;
215 } 242 }
216 dev_dbg(dev, "registered child %s\n", proxy->dev.bus_id); 243 dev_dbg(dev, "registered child %s\n", proxy->dev.bus_id);
217 return proxy; 244 return proxy;
245
246fail:
247 class_device_put(&master->cdev);
248 kfree(proxy);
249 return NULL;
218} 250}
219EXPORT_SYMBOL_GPL(spi_new_device); 251EXPORT_SYMBOL_GPL(spi_new_device);
220 252
@@ -237,11 +269,11 @@ spi_register_board_info(struct spi_board_info const *info, unsigned n)
237{ 269{
238 struct boardinfo *bi; 270 struct boardinfo *bi;
239 271
240 bi = kmalloc (sizeof (*bi) + n * sizeof (*info), GFP_KERNEL); 272 bi = kmalloc(sizeof(*bi) + n * sizeof *info, GFP_KERNEL);
241 if (!bi) 273 if (!bi)
242 return -ENOMEM; 274 return -ENOMEM;
243 bi->n_board_info = n; 275 bi->n_board_info = n;
244 memcpy(bi->board_info, info, n * sizeof (*info)); 276 memcpy(bi->board_info, info, n * sizeof *info);
245 277
246 down(&board_lock); 278 down(&board_lock);
247 list_add_tail(&bi->list, &board_list); 279 list_add_tail(&bi->list, &board_list);
@@ -330,6 +362,7 @@ spi_alloc_master(struct device *dev, unsigned size)
330 if (!master) 362 if (!master)
331 return NULL; 363 return NULL;
332 364
365 class_device_initialize(&master->cdev);
333 master->cdev.class = &spi_master_class; 366 master->cdev.class = &spi_master_class;
334 master->cdev.dev = get_device(dev); 367 master->cdev.dev = get_device(dev);
335 class_set_devdata(&master->cdev, &master[1]); 368 class_set_devdata(&master->cdev, &master[1]);
@@ -366,7 +399,7 @@ spi_register_master(struct spi_master *master)
366 /* convention: dynamically assigned bus IDs count down from the max */ 399 /* convention: dynamically assigned bus IDs count down from the max */
367 if (master->bus_num == 0) { 400 if (master->bus_num == 0) {
368 master->bus_num = atomic_dec_return(&dyn_bus_id); 401 master->bus_num = atomic_dec_return(&dyn_bus_id);
369 dynamic = 0; 402 dynamic = 1;
370 } 403 }
371 404
372 /* register the device, then userspace will see it. 405 /* register the device, then userspace will see it.
@@ -374,11 +407,9 @@ spi_register_master(struct spi_master *master)
374 */ 407 */
375 snprintf(master->cdev.class_id, sizeof master->cdev.class_id, 408 snprintf(master->cdev.class_id, sizeof master->cdev.class_id,
376 "spi%u", master->bus_num); 409 "spi%u", master->bus_num);
377 status = class_device_register(&master->cdev); 410 status = class_device_add(&master->cdev);
378 if (status < 0) { 411 if (status < 0)
379 class_device_put(&master->cdev);
380 goto done; 412 goto done;
381 }
382 dev_dbg(dev, "registered master %s%s\n", master->cdev.class_id, 413 dev_dbg(dev, "registered master %s%s\n", master->cdev.class_id,
383 dynamic ? " (dynamic)" : ""); 414 dynamic ? " (dynamic)" : "");
384 415
@@ -491,6 +522,7 @@ static u8 *buf;
491 * This performs a half duplex MicroWire style transaction with the 522 * This performs a half duplex MicroWire style transaction with the
492 * device, sending txbuf and then reading rxbuf. The return value 523 * device, sending txbuf and then reading rxbuf. The return value
493 * is zero for success, else a negative errno status code. 524 * is zero for success, else a negative errno status code.
525 * This call may only be used from a context that may sleep.
494 * 526 *
495 * Parameters to this routine are always copied using a small buffer, 527 * Parameters to this routine are always copied using a small buffer,
496 * large transfers should use use spi_{async,sync}() calls with 528 * large transfers should use use spi_{async,sync}() calls with
@@ -553,16 +585,38 @@ EXPORT_SYMBOL_GPL(spi_write_then_read);
553 585
554static int __init spi_init(void) 586static int __init spi_init(void)
555{ 587{
588 int status;
589
556 buf = kmalloc(SPI_BUFSIZ, SLAB_KERNEL); 590 buf = kmalloc(SPI_BUFSIZ, SLAB_KERNEL);
557 if (!buf) 591 if (!buf) {
558 return -ENOMEM; 592 status = -ENOMEM;
593 goto err0;
594 }
595
596 status = bus_register(&spi_bus_type);
597 if (status < 0)
598 goto err1;
559 599
560 bus_register(&spi_bus_type); 600 status = class_register(&spi_master_class);
561 class_register(&spi_master_class); 601 if (status < 0)
602 goto err2;
562 return 0; 603 return 0;
604
605err2:
606 bus_unregister(&spi_bus_type);
607err1:
608 kfree(buf);
609 buf = NULL;
610err0:
611 return status;
563} 612}
613
564/* board_info is normally registered in arch_initcall(), 614/* board_info is normally registered in arch_initcall(),
565 * but even essential drivers wait till later 615 * but even essential drivers wait till later
616 *
617 * REVISIT only boardinfo really needs static linking. the rest (device and
618 * driver registration) _could_ be dynamically linked (modular) ... costs
619 * include needing to have boardinfo data structures be much more public.
566 */ 620 */
567subsys_initcall(spi_init); 621subsys_initcall(spi_init);
568 622