diff options
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi.c | 118 |
1 files changed, 86 insertions, 32 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 7cd356b1764..2ecb86cb368 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -26,13 +26,9 @@ #include <linux/spi/spi.h> -/* SPI bustype and spi_master class are registered during early boot, - * usually before board init code provides the SPI device tables, and - * are available later when driver init code needs them. - * - * Drivers for SPI devices started out like those for platform bus - * devices. But both have changed in 2.6.15; maybe this should get - * an "spi_driver" structure at some point (not currently needed) +/* SPI bustype and spi_master class are registered after board init code + * provides the SPI device tables, ensuring that both are present by the + * time controller driver registration causes spi_devices to "enumerate". */ static void spidev_release(struct device *dev) { @@ -83,10 +79,7 @@ static int spi_uevent(struct device *dev, char **envp, int num_envp, #ifdef CONFIG_PM -/* Suspend/resume in "struct device_driver" don't really need that - * strange third parameter, so we just make it a constant and expect - * SPI drivers to ignore it just like most platform drivers do. - * +/* * NOTE: the suspend() method for an spi_master controller driver * should verify that all its child devices are marked as suspended; * 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, */ static int spi_suspend(struct device *dev, pm_message_t message) { - int value; + int value; + struct spi_driver *drv = to_spi_driver(dev->driver); - if (!dev->driver || !dev->driver->suspend) + if (!drv || !drv->suspend) return 0; /* suspend will stop irqs and dma; no more i/o */ - value = dev->driver->suspend(dev, message); + value = drv->suspend(to_spi_device(dev), message); if (value == 0) dev->power.power_state = message; return value; @@ -108,13 +102,14 @@ static int spi_suspend(struct device *dev, pm_message_t message) static int spi_resume(struct device *dev) { - int value; + int value; + struct spi_driver *drv = to_spi_driver(dev->driver); - if (!dev->driver || !dev->driver->resume) + if (!drv || !drv->resume) return 0; /* resume may restart the i/o queue */ - value = dev->driver->resume(dev); + value = drv->resume(to_spi_device(dev)); if (value == 0) dev->power.power_state = PMSG_ON; return value; @@ -135,6 +130,41 @@ struct bus_type spi_bus_type = { }; EXPORT_SYMBOL_GPL(spi_bus_type); + +static int spi_drv_probe(struct device *dev) +{ + const struct spi_driver *sdrv = to_spi_driver(dev->driver); + + return sdrv->probe(to_spi_device(dev)); +} + +static int spi_drv_remove(struct device *dev) +{ + const struct spi_driver *sdrv = to_spi_driver(dev->driver); + + return sdrv->remove(to_spi_device(dev)); +} + +static void spi_drv_shutdown(struct device *dev) +{ + const struct spi_driver *sdrv = to_spi_driver(dev->driver); + + sdrv->shutdown(to_spi_device(dev)); +} + +int spi_register_driver(struct spi_driver *sdrv) +{ + sdrv->driver.bus = &spi_bus_type; + if (sdrv->probe) + sdrv->driver.probe = spi_drv_probe; + if (sdrv->remove) + sdrv->driver.remove = spi_drv_remove; + if (sdrv->shutdown) + sdrv->driver.shutdown = spi_drv_shutdown; + return driver_register(&sdrv->driver); +} +EXPORT_SYMBOL_GPL(spi_register_driver); + /*-------------------------------------------------------------------------*/ /* 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) if (status < 0) { dev_dbg(dev, "can't %s %s, status %d\n", "add", proxy->dev.bus_id, status); -fail: - class_device_put(&master->cdev); - kfree(proxy); - return NULL; + goto fail; } dev_dbg(dev, "registered child %s\n", proxy->dev.bus_id); return proxy; + +fail: + class_device_put(&master->cdev); + kfree(proxy); + return NULL; } EXPORT_SYMBOL_GPL(spi_new_device); @@ -237,11 +269,11 @@ spi_register_board_info(struct spi_board_info const *info, unsigned n) { struct boardinfo *bi; - bi = kmalloc (sizeof (*bi) + n * sizeof (*info), GFP_KERNEL); + bi = kmalloc(sizeof(*bi) + n * sizeof *info, GFP_KERNEL); if (!bi) return -ENOMEM; bi->n_board_info = n; - memcpy(bi->board_info, info, n * sizeof (*info)); + memcpy(bi->board_info, info, n * sizeof *info); down(&board_lock); list_add_tail(&bi->list, &board_list); @@ -330,6 +362,7 @@ spi_alloc_master(struct device *dev, unsigned size) if (!master) return NULL; + class_device_initialize(&master->cdev); master->cdev.class = &spi_master_class; master->cdev.dev = get_device(dev); class_set_devdata(&master->cdev, &master[1]); @@ -366,7 +399,7 @@ spi_register_master(struct spi_master *master) /* convention: dynamically assigned bus IDs count down from the max */ if (master->bus_num == 0) { master->bus_num = atomic_dec_return(&dyn_bus_id); - dynamic = 0; + dynamic = 1; } /* register the device, then userspace will see it. @@ -374,11 +407,9 @@ spi_register_master(struct spi_master *master) */ snprintf(master->cdev.class_id, sizeof master->cdev.class_id, "spi%u", master->bus_num); - status = class_device_register(&master->cdev); - if (status < 0) { - class_device_put(&master->cdev); + status = class_device_add(&master->cdev); + if (status < 0) goto done; - } dev_dbg(dev, "registered master %s%s\n", master->cdev.class_id, dynamic ? " (dynamic)" : ""); @@ -491,6 +522,7 @@ static u8 *buf; * This performs a half duplex MicroWire style transaction with the * device, sending txbuf and then reading rxbuf. The return value * is zero for success, else a negative errno status code. + * This call may only be used from a context that may sleep. * * Parameters to this routine are always copied using a small buffer, * large transfers should use use spi_{async,sync}() calls with @@ -553,16 +585,38 @@ EXPORT_SYMBOL_GPL(spi_write_then_read); static int __init spi_init(void) { + int status; + buf = kmalloc(SPI_BUFSIZ, SLAB_KERNEL); - if (!buf) - return -ENOMEM; + if (!buf) { + status = -ENOMEM; + goto err0; + } + + status = bus_register(&spi_bus_type); + if (status < 0) + goto err1; - bus_register(&spi_bus_type); - class_register(&spi_master_class); + status = class_register(&spi_master_class); + if (status < 0) + goto err2; return 0; + +err2: + bus_unregister(&spi_bus_type); +err1: + kfree(buf); + buf = NULL; +err0: + return status; } + /* board_info is normally registered in arch_initcall(), * but even essential drivers wait till later + * + * REVISIT only boardinfo really needs static linking. the rest (device and + * driver registration) _could_ be dynamically linked (modular) ... costs + * include needing to have boardinfo data structures be much more public. */ subsys_initcall(spi_init); |