diff options
Diffstat (limited to 'drivers/spi/spi.c')
-rw-r--r-- | drivers/spi/spi.c | 110 |
1 files changed, 70 insertions, 40 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 4fcbb0aa71d3..cf8ee5e48f73 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -40,9 +40,13 @@ #include <linux/ioport.h> #include <linux/acpi.h> #include <linux/highmem.h> +#include <linux/idr.h> #define CREATE_TRACE_POINTS #include <trace/events/spi.h> +#define SPI_DYN_FIRST_BUS_NUM 0 + +static DEFINE_IDR(spi_master_idr); static void spidev_release(struct device *dev) { @@ -321,8 +325,7 @@ static int spi_uevent(struct device *dev, struct kobj_uevent_env *env) if (rc != -ENODEV) return rc; - add_uevent_var(env, "MODALIAS=%s%s", SPI_MODULE_PREFIX, spi->modalias); - return 0; + return add_uevent_var(env, "MODALIAS=%s%s", SPI_MODULE_PREFIX, spi->modalias); } struct bus_type spi_bus_type = { @@ -421,6 +424,7 @@ static LIST_HEAD(spi_controller_list); /* * Used to protect add/del opertion for board_info list and * spi_controller list, and their matching process + * also used to protect object of type struct idr */ static DEFINE_MUTEX(board_lock); @@ -1533,15 +1537,15 @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi, int rc; /* Mode (clock phase/polarity/etc.) */ - if (of_find_property(nc, "spi-cpha", NULL)) + if (of_property_read_bool(nc, "spi-cpha")) spi->mode |= SPI_CPHA; - if (of_find_property(nc, "spi-cpol", NULL)) + if (of_property_read_bool(nc, "spi-cpol")) spi->mode |= SPI_CPOL; - if (of_find_property(nc, "spi-cs-high", NULL)) + if (of_property_read_bool(nc, "spi-cs-high")) spi->mode |= SPI_CS_HIGH; - if (of_find_property(nc, "spi-3wire", NULL)) + if (of_property_read_bool(nc, "spi-3wire")) spi->mode |= SPI_3WIRE; - if (of_find_property(nc, "spi-lsb-first", NULL)) + if (of_property_read_bool(nc, "spi-lsb-first")) spi->mode |= SPI_LSB_FIRST; /* Device DUAL/QUAD mode */ @@ -1583,8 +1587,8 @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi, if (spi_controller_is_slave(ctlr)) { if (strcmp(nc->name, "slave")) { - dev_err(&ctlr->dev, "%s is not called 'slave'\n", - nc->full_name); + dev_err(&ctlr->dev, "%pOF is not called 'slave'\n", + nc); return -EINVAL; } return 0; @@ -1593,8 +1597,8 @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi, /* Device address */ rc = of_property_read_u32(nc, "reg", &value); if (rc) { - dev_err(&ctlr->dev, "%s has no valid 'reg' property (%d)\n", - nc->full_name, rc); + dev_err(&ctlr->dev, "%pOF has no valid 'reg' property (%d)\n", + nc, rc); return rc; } spi->chip_select = value; @@ -1603,8 +1607,7 @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi, rc = of_property_read_u32(nc, "spi-max-frequency", &value); if (rc) { dev_err(&ctlr->dev, - "%s has no valid 'spi-max-frequency' property (%d)\n", - nc->full_name, rc); + "%pOF has no valid 'spi-max-frequency' property (%d)\n", nc, rc); return rc; } spi->max_speed_hz = value; @@ -1621,8 +1624,7 @@ of_register_spi_device(struct spi_controller *ctlr, struct device_node *nc) /* Alloc an spi_device */ spi = spi_alloc_device(ctlr); if (!spi) { - dev_err(&ctlr->dev, "spi_device alloc error for %s\n", - nc->full_name); + dev_err(&ctlr->dev, "spi_device alloc error for %pOF\n", nc); rc = -ENOMEM; goto err_out; } @@ -1631,8 +1633,7 @@ of_register_spi_device(struct spi_controller *ctlr, struct device_node *nc) rc = of_modalias_node(nc, spi->modalias, sizeof(spi->modalias)); if (rc < 0) { - dev_err(&ctlr->dev, "cannot find modalias for %s\n", - nc->full_name); + dev_err(&ctlr->dev, "cannot find modalias for %pOF\n", nc); goto err_out; } @@ -1647,8 +1648,7 @@ of_register_spi_device(struct spi_controller *ctlr, struct device_node *nc) /* Register the new device */ rc = spi_add_device(spi); if (rc) { - dev_err(&ctlr->dev, "spi_device register error %s\n", - nc->full_name); + dev_err(&ctlr->dev, "spi_device register error %pOF\n", nc); goto err_of_node_put; } @@ -1682,8 +1682,7 @@ static void of_register_spi_devices(struct spi_controller *ctlr) spi = of_register_spi_device(ctlr, nc); if (IS_ERR(spi)) { dev_warn(&ctlr->dev, - "Failed to create SPI device for %s\n", - nc->full_name); + "Failed to create SPI device for %pOF\n", nc); of_node_clear_flag(nc, OF_POPULATED); } } @@ -2052,11 +2051,10 @@ static int of_spi_register_master(struct spi_controller *ctlr) */ int spi_register_controller(struct spi_controller *ctlr) { - static atomic_t dyn_bus_id = ATOMIC_INIT((1<<15) - 1); struct device *dev = ctlr->dev.parent; struct boardinfo *bi; int status = -ENODEV; - int dynamic = 0; + int id; if (!dev) return -ENODEV; @@ -2072,19 +2070,28 @@ int spi_register_controller(struct spi_controller *ctlr) */ if (ctlr->num_chipselect == 0) return -EINVAL; - - if ((ctlr->bus_num < 0) && ctlr->dev.of_node) - ctlr->bus_num = of_alias_get_id(ctlr->dev.of_node, "spi"); - - /* convention: dynamically assigned bus IDs count down from the max */ + /* allocate dynamic bus number using Linux idr */ + if ((ctlr->bus_num < 0) && ctlr->dev.of_node) { + id = of_alias_get_id(ctlr->dev.of_node, "spi"); + if (id >= 0) { + ctlr->bus_num = id; + mutex_lock(&board_lock); + id = idr_alloc(&spi_master_idr, ctlr, ctlr->bus_num, + ctlr->bus_num + 1, GFP_KERNEL); + mutex_unlock(&board_lock); + if (WARN(id < 0, "couldn't get idr")) + return id == -ENOSPC ? -EBUSY : id; + } + } if (ctlr->bus_num < 0) { - /* FIXME switch to an IDR based scheme, something like - * I2C now uses, so we can't run out of "dynamic" IDs - */ - ctlr->bus_num = atomic_dec_return(&dyn_bus_id); - dynamic = 1; + mutex_lock(&board_lock); + id = idr_alloc(&spi_master_idr, ctlr, SPI_DYN_FIRST_BUS_NUM, 0, + GFP_KERNEL); + mutex_unlock(&board_lock); + if (WARN(id < 0, "couldn't get idr")) + return id; + ctlr->bus_num = id; } - INIT_LIST_HEAD(&ctlr->queue); spin_lock_init(&ctlr->queue_lock); spin_lock_init(&ctlr->bus_lock_spinlock); @@ -2100,11 +2107,16 @@ int spi_register_controller(struct spi_controller *ctlr) */ dev_set_name(&ctlr->dev, "spi%u", ctlr->bus_num); status = device_add(&ctlr->dev); - if (status < 0) + if (status < 0) { + /* free bus id */ + mutex_lock(&board_lock); + idr_remove(&spi_master_idr, ctlr->bus_num); + mutex_unlock(&board_lock); goto done; - dev_dbg(dev, "registered %s %s%s\n", + } + dev_dbg(dev, "registered %s %s\n", spi_controller_is_slave(ctlr) ? "slave" : "master", - dev_name(&ctlr->dev), dynamic ? " (dynamic)" : ""); + dev_name(&ctlr->dev)); /* If we're using a queued driver, start the queue */ if (ctlr->transfer) @@ -2113,6 +2125,10 @@ int spi_register_controller(struct spi_controller *ctlr) status = spi_controller_initialize_queue(ctlr); if (status) { device_del(&ctlr->dev); + /* free bus id */ + mutex_lock(&board_lock); + idr_remove(&spi_master_idr, ctlr->bus_num); + mutex_unlock(&board_lock); goto done; } } @@ -2191,19 +2207,33 @@ static int __unregister(struct device *dev, void *null) */ void spi_unregister_controller(struct spi_controller *ctlr) { + struct spi_controller *found; int dummy; + /* First make sure that this controller was ever added */ + mutex_lock(&board_lock); + found = idr_find(&spi_master_idr, ctlr->bus_num); + mutex_unlock(&board_lock); + if (found != ctlr) { + dev_dbg(&ctlr->dev, + "attempting to delete unregistered controller [%s]\n", + dev_name(&ctlr->dev)); + return; + } if (ctlr->queued) { if (spi_destroy_queue(ctlr)) dev_err(&ctlr->dev, "queue remove failed\n"); } - mutex_lock(&board_lock); list_del(&ctlr->list); mutex_unlock(&board_lock); dummy = device_for_each_child(&ctlr->dev, NULL, __unregister); device_unregister(&ctlr->dev); + /* free bus id */ + mutex_lock(&board_lock); + idr_remove(&spi_master_idr, ctlr->bus_num); + mutex_unlock(&board_lock); } EXPORT_SYMBOL_GPL(spi_unregister_controller); @@ -3311,8 +3341,8 @@ static int of_spi_notify(struct notifier_block *nb, unsigned long action, put_device(&ctlr->dev); if (IS_ERR(spi)) { - pr_err("%s: failed to create for '%s'\n", - __func__, rd->dn->full_name); + pr_err("%s: failed to create for '%pOF'\n", + __func__, rd->dn); of_node_clear_flag(rd->dn, OF_POPULATED); return notifier_from_errno(PTR_ERR(spi)); } |