diff options
Diffstat (limited to 'drivers/spi/spi.c')
| -rw-r--r-- | drivers/spi/spi.c | 244 |
1 files changed, 201 insertions, 43 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 9e039c60c068..8d05accf706c 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -39,6 +39,9 @@ #include <linux/ioport.h> #include <linux/acpi.h> +#define CREATE_TRACE_POINTS +#include <trace/events/spi.h> + static void spidev_release(struct device *dev) { struct spi_device *spi = to_spi_device(dev); @@ -58,11 +61,13 @@ modalias_show(struct device *dev, struct device_attribute *a, char *buf) return sprintf(buf, "%s%s\n", SPI_MODULE_PREFIX, spi->modalias); } +static DEVICE_ATTR_RO(modalias); -static struct device_attribute spi_dev_attrs[] = { - __ATTR_RO(modalias), - __ATTR_NULL, +static struct attribute *spi_dev_attrs[] = { + &dev_attr_modalias.attr, + NULL, }; +ATTRIBUTE_GROUPS(spi_dev); /* modalias support makes "modprobe $MODALIAS" new-style hotplug work, * and the sysfs version makes coldplug work too. @@ -229,7 +234,7 @@ static const struct dev_pm_ops spi_pm = { struct bus_type spi_bus_type = { .name = "spi", - .dev_attrs = spi_dev_attrs, + .dev_groups = spi_dev_groups, .match = spi_match_device, .uevent = spi_uevent, .pm = &spi_pm, @@ -323,7 +328,7 @@ struct spi_device *spi_alloc_device(struct spi_master *master) if (!spi_master_get(master)) return NULL; - spi = kzalloc(sizeof *spi, GFP_KERNEL); + spi = kzalloc(sizeof(*spi), GFP_KERNEL); if (!spi) { dev_err(dev, "cannot alloc spi_device\n"); spi_master_put(master); @@ -523,6 +528,95 @@ int spi_register_board_info(struct spi_board_info const *info, unsigned n) /*-------------------------------------------------------------------------*/ +static void spi_set_cs(struct spi_device *spi, bool enable) +{ + if (spi->mode & SPI_CS_HIGH) + enable = !enable; + + if (spi->cs_gpio >= 0) + gpio_set_value(spi->cs_gpio, !enable); + else if (spi->master->set_cs) + spi->master->set_cs(spi, !enable); +} + +/* + * spi_transfer_one_message - Default implementation of transfer_one_message() + * + * This is a standard implementation of transfer_one_message() for + * drivers which impelment a transfer_one() operation. It provides + * standard handling of delays and chip select management. + */ +static int spi_transfer_one_message(struct spi_master *master, + struct spi_message *msg) +{ + struct spi_transfer *xfer; + bool cur_cs = true; + bool keep_cs = false; + int ret = 0; + + spi_set_cs(msg->spi, true); + + list_for_each_entry(xfer, &msg->transfers, transfer_list) { + trace_spi_transfer_start(msg, xfer); + + INIT_COMPLETION(master->xfer_completion); + + ret = master->transfer_one(master, msg->spi, xfer); + if (ret < 0) { + dev_err(&msg->spi->dev, + "SPI transfer failed: %d\n", ret); + goto out; + } + + if (ret > 0) + wait_for_completion(&master->xfer_completion); + + trace_spi_transfer_stop(msg, xfer); + + if (msg->status != -EINPROGRESS) + goto out; + + if (xfer->delay_usecs) + udelay(xfer->delay_usecs); + + if (xfer->cs_change) { + if (list_is_last(&xfer->transfer_list, + &msg->transfers)) { + keep_cs = true; + } else { + cur_cs = !cur_cs; + spi_set_cs(msg->spi, cur_cs); + } + } + + msg->actual_length += xfer->len; + } + +out: + if (ret != 0 || !keep_cs) + spi_set_cs(msg->spi, false); + + if (msg->status == -EINPROGRESS) + msg->status = ret; + + spi_finalize_current_message(master); + + return ret; +} + +/** + * spi_finalize_current_transfer - report completion of a transfer + * + * Called by SPI drivers using the core transfer_one_message() + * implementation to notify it that the current interrupt driven + * transfer has finised and the next one may be scheduled. + */ +void spi_finalize_current_transfer(struct spi_master *master) +{ + complete(&master->xfer_completion); +} +EXPORT_SYMBOL_GPL(spi_finalize_current_transfer); + /** * spi_pump_messages - kthread work function which processes spi message queue * @work: pointer to kthread work struct contained in the master struct @@ -557,6 +651,7 @@ static void spi_pump_messages(struct kthread_work *work) pm_runtime_mark_last_busy(master->dev.parent); pm_runtime_put_autosuspend(master->dev.parent); } + trace_spi_master_idle(master); return; } @@ -585,6 +680,9 @@ static void spi_pump_messages(struct kthread_work *work) } } + if (!was_busy) + trace_spi_master_busy(master); + if (!was_busy && master->prepare_transfer_hardware) { ret = master->prepare_transfer_hardware(master); if (ret) { @@ -597,6 +695,20 @@ static void spi_pump_messages(struct kthread_work *work) } } + trace_spi_message_start(master->cur_msg); + + if (master->prepare_message) { + ret = master->prepare_message(master, master->cur_msg); + if (ret) { + dev_err(&master->dev, + "failed to prepare message: %d\n", ret); + master->cur_msg->status = ret; + spi_finalize_current_message(master); + return; + } + master->cur_msg_prepared = true; + } + ret = master->transfer_one_message(master, master->cur_msg); if (ret) { dev_err(&master->dev, @@ -678,6 +790,7 @@ void spi_finalize_current_message(struct spi_master *master) { struct spi_message *mesg; unsigned long flags; + int ret; spin_lock_irqsave(&master->queue_lock, flags); mesg = master->cur_msg; @@ -686,9 +799,20 @@ void spi_finalize_current_message(struct spi_master *master) queue_kthread_work(&master->kworker, &master->pump_messages); spin_unlock_irqrestore(&master->queue_lock, flags); + if (master->cur_msg_prepared && master->unprepare_message) { + ret = master->unprepare_message(master, mesg); + if (ret) { + dev_err(&master->dev, + "failed to unprepare message: %d\n", ret); + } + } + master->cur_msg_prepared = false; + mesg->state = NULL; if (mesg->complete) mesg->complete(mesg->context); + + trace_spi_message_done(mesg); } EXPORT_SYMBOL_GPL(spi_finalize_current_message); @@ -803,6 +927,8 @@ static int spi_master_initialize_queue(struct spi_master *master) master->queued = true; master->transfer = spi_queued_transfer; + if (!master->transfer_one_message) + master->transfer_one_message = spi_transfer_one_message; /* Initialize and start queue */ ret = spi_init_queue(master); @@ -838,10 +964,8 @@ static void of_register_spi_devices(struct spi_master *master) { struct spi_device *spi; struct device_node *nc; - const __be32 *prop; - char modalias[SPI_NAME_SIZE + 4]; int rc; - int len; + u32 value; if (!master->dev.of_node) return; @@ -866,14 +990,14 @@ static void of_register_spi_devices(struct spi_master *master) } /* Device address */ - prop = of_get_property(nc, "reg", &len); - if (!prop || len < sizeof(*prop)) { - dev_err(&master->dev, "%s has no 'reg' property\n", - nc->full_name); + rc = of_property_read_u32(nc, "reg", &value); + if (rc) { + dev_err(&master->dev, "%s has no valid 'reg' property (%d)\n", + nc->full_name, rc); spi_dev_put(spi); continue; } - spi->chip_select = be32_to_cpup(prop); + spi->chip_select = value; /* Mode (clock phase/polarity/etc.) */ if (of_find_property(nc, "spi-cpha", NULL)) @@ -886,55 +1010,53 @@ static void of_register_spi_devices(struct spi_master *master) spi->mode |= SPI_3WIRE; /* Device DUAL/QUAD mode */ - prop = of_get_property(nc, "spi-tx-bus-width", &len); - if (prop && len == sizeof(*prop)) { - switch (be32_to_cpup(prop)) { - case SPI_NBITS_SINGLE: + if (!of_property_read_u32(nc, "spi-tx-bus-width", &value)) { + switch (value) { + case 1: break; - case SPI_NBITS_DUAL: + case 2: spi->mode |= SPI_TX_DUAL; break; - case SPI_NBITS_QUAD: + case 4: spi->mode |= SPI_TX_QUAD; break; default: dev_err(&master->dev, "spi-tx-bus-width %d not supported\n", - be32_to_cpup(prop)); + value); spi_dev_put(spi); continue; } } - prop = of_get_property(nc, "spi-rx-bus-width", &len); - if (prop && len == sizeof(*prop)) { - switch (be32_to_cpup(prop)) { - case SPI_NBITS_SINGLE: + if (!of_property_read_u32(nc, "spi-rx-bus-width", &value)) { + switch (value) { + case 1: break; - case SPI_NBITS_DUAL: + case 2: spi->mode |= SPI_RX_DUAL; break; - case SPI_NBITS_QUAD: + case 4: spi->mode |= SPI_RX_QUAD; break; default: dev_err(&master->dev, "spi-rx-bus-width %d not supported\n", - be32_to_cpup(prop)); + value); spi_dev_put(spi); continue; } } /* Device speed */ - prop = of_get_property(nc, "spi-max-frequency", &len); - if (!prop || len < sizeof(*prop)) { - dev_err(&master->dev, "%s has no 'spi-max-frequency' property\n", - nc->full_name); + rc = of_property_read_u32(nc, "spi-max-frequency", &value); + if (rc) { + dev_err(&master->dev, "%s has no valid 'spi-max-frequency' property (%d)\n", + nc->full_name, rc); spi_dev_put(spi); continue; } - spi->max_speed_hz = be32_to_cpup(prop); + spi->max_speed_hz = value; /* IRQ */ spi->irq = irq_of_parse_and_map(nc, 0); @@ -944,9 +1066,7 @@ static void of_register_spi_devices(struct spi_master *master) spi->dev.of_node = nc; /* Register the new device */ - snprintf(modalias, sizeof(modalias), "%s%s", SPI_MODULE_PREFIX, - spi->modalias); - request_module(modalias); + request_module("%s%s", SPI_MODULE_PREFIX, spi->modalias); rc = spi_add_device(spi); if (rc) { dev_err(&master->dev, "spi_device register error %s\n", @@ -1025,7 +1145,7 @@ static acpi_status acpi_spi_add_device(acpi_handle handle, u32 level, return AE_OK; } - strlcpy(spi->modalias, dev_name(&adev->dev), sizeof(spi->modalias)); + strlcpy(spi->modalias, acpi_device_hid(adev), sizeof(spi->modalias)); if (spi_add_device(spi)) { dev_err(&master->dev, "failed to add SPI device %s from ACPI\n", dev_name(&adev->dev)); @@ -1097,7 +1217,7 @@ struct spi_master *spi_alloc_master(struct device *dev, unsigned size) if (!dev) return NULL; - master = kzalloc(size + sizeof *master, GFP_KERNEL); + master = kzalloc(size + sizeof(*master), GFP_KERNEL); if (!master) return NULL; @@ -1122,7 +1242,7 @@ static int of_spi_register_master(struct spi_master *master) return 0; nb = of_gpio_named_count(np, "cs-gpios"); - master->num_chipselect = max(nb, (int)master->num_chipselect); + master->num_chipselect = max_t(int, nb, master->num_chipselect); /* Return error only for an incorrectly formed cs-gpios property */ if (nb == 0 || nb == -ENOENT) @@ -1209,6 +1329,7 @@ int spi_register_master(struct spi_master *master) spin_lock_init(&master->bus_lock_spinlock); mutex_init(&master->bus_lock_mutex); master->bus_lock_flag = 0; + init_completion(&master->xfer_completion); /* register the device, then userspace will see it. * registration fails if the bus ID is in use. @@ -1245,6 +1366,41 @@ done: } EXPORT_SYMBOL_GPL(spi_register_master); +static void devm_spi_unregister(struct device *dev, void *res) +{ + spi_unregister_master(*(struct spi_master **)res); +} + +/** + * dev_spi_register_master - register managed SPI master controller + * @dev: device managing SPI master + * @master: initialized master, originally from spi_alloc_master() + * Context: can sleep + * + * Register a SPI device as with spi_register_master() which will + * automatically be unregister + */ +int devm_spi_register_master(struct device *dev, struct spi_master *master) +{ + struct spi_master **ptr; + int ret; + + ptr = devres_alloc(devm_spi_unregister, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return -ENOMEM; + + ret = spi_register_master(master); + if (ret != 0) { + *ptr = master; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return ret; +} +EXPORT_SYMBOL_GPL(devm_spi_register_master); + static int __unregister(struct device *dev, void *null) { spi_unregister_device(to_spi_device(dev)); @@ -1402,8 +1558,7 @@ int spi_setup(struct spi_device *spi) if (spi->master->setup) status = spi->master->setup(spi); - dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s" - "%u bits/w, %u Hz max --> %d\n", + dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s%u bits/w, %u Hz max --> %d\n", (int) (spi->mode & (SPI_CPOL | SPI_CPHA)), (spi->mode & SPI_CS_HIGH) ? "cs_high, " : "", (spi->mode & SPI_LSB_FIRST) ? "lsb, " : "", @@ -1421,6 +1576,10 @@ static int __spi_async(struct spi_device *spi, struct spi_message *message) struct spi_master *master = spi->master; struct spi_transfer *xfer; + message->spi = spi; + + trace_spi_message_submit(message); + if (list_empty(&message->transfers)) return -EINVAL; if (!message->complete) @@ -1520,7 +1679,6 @@ static int __spi_async(struct spi_device *spi, struct spi_message *message) } } - message->spi = spi; message->status = -EINPROGRESS; return master->transfer(spi, message); } @@ -1762,7 +1920,7 @@ int spi_bus_unlock(struct spi_master *master) EXPORT_SYMBOL_GPL(spi_bus_unlock); /* portable code must never pass more than 32 bytes */ -#define SPI_BUFSIZ max(32,SMP_CACHE_BYTES) +#define SPI_BUFSIZ max(32, SMP_CACHE_BYTES) static u8 *buf; @@ -1811,7 +1969,7 @@ int spi_write_then_read(struct spi_device *spi, } spi_message_init(&message); - memset(x, 0, sizeof x); + memset(x, 0, sizeof(x)); if (n_tx) { x[0].len = n_tx; spi_message_add_tail(&x[0], &message); |