Add the bus handler registration needed for performing overlays containing spi devices.
Signed-off-by: Pantelis Antoniou <[email protected]> --- drivers/spi/spi.c | 345 ++++++++++++++++++++++++++++++++++++++---------------- 1 file changed, 242 insertions(+), 103 deletions(-) diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 4eb9bf0..dac5573 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1179,6 +1179,123 @@ err_init_queue: /*-------------------------------------------------------------------------*/ #if defined(CONFIG_OF) + +static struct spi_device * +of_register_spi_device(struct spi_master *master, struct device_node *node) +{ + struct spi_device *spi; + struct device_node *nc; + int err; + u32 value; + + /* Alloc an spi_device */ + spi = spi_alloc_device(master); + if (!spi) { + dev_err(&master->dev, "spi_device alloc error for %s\n", + nc->full_name); + err = -ENOMEM; + goto err_out; + } + + /* Select device driver */ + err = of_modalias_node(nc, spi->modalias, + sizeof(spi->modalias)); + if (err) { + dev_err(&master->dev, "cannot find modalias for %s\n", + nc->full_name); + goto err_out; + } + + /* Device address */ + err = of_property_read_u32(nc, "reg", &value); + if (err) { + dev_err(&master->dev, "%s has no valid 'reg' property (%d)\n", + nc->full_name, err); + goto err_out; + } + spi->chip_select = value; + + /* Mode (clock phase/polarity/etc.) */ + if (of_find_property(nc, "spi-cpha", NULL)) + spi->mode |= SPI_CPHA; + if (of_find_property(nc, "spi-cpol", NULL)) + spi->mode |= SPI_CPOL; + if (of_find_property(nc, "spi-cs-high", NULL)) + spi->mode |= SPI_CS_HIGH; + if (of_find_property(nc, "spi-3wire", NULL)) + spi->mode |= SPI_3WIRE; + + /* Device DUAL/QUAD mode */ + if (!of_property_read_u32(nc, "spi-tx-bus-width", &value)) { + switch (value) { + case 1: + break; + case 2: + spi->mode |= SPI_TX_DUAL; + break; + case 4: + spi->mode |= SPI_TX_QUAD; + break; + default: + dev_err(&master->dev, + "spi-tx-bus-width %d not supported\n", + value); + err = -EINVAL; + goto err_out; + } + } + + if (!of_property_read_u32(nc, "spi-rx-bus-width", &value)) { + switch (value) { + case 1: + break; + case 2: + spi->mode |= SPI_RX_DUAL; + break; + case 4: + spi->mode |= SPI_RX_QUAD; + break; + default: + dev_err(&master->dev, + "spi-rx-bus-width %d not supported\n", + value); + err = -EINVAL; + goto err_out; + } + } + + /* Device speed */ + err = of_property_read_u32(nc, "spi-max-frequency", &value); + if (err) { + dev_err(&master->dev, "%s has no valid 'spi-max-frequency' property (%d)\n", + nc->full_name, err); + goto err_out; + } + spi->max_speed_hz = value; + + /* IRQ */ + spi->irq = irq_of_parse_and_map(nc, 0); + + /* Store a pointer to the node in the device structure */ + of_node_get(nc); + spi->dev.of_node = nc; + + /* Register the new device */ + request_module("%s%s", SPI_MODULE_PREFIX, spi->modalias); + err = spi_add_device(spi); + if (err) { + dev_err(&master->dev, "spi_device register error %s\n", + nc->full_name); + goto err_out; + } + + return spi; + +err_out: + spi_dev_put(spi); + return ERR_PTR(err); +} + /** * of_register_spi_devices() - Register child devices onto the SPI bus * @master: Pointer to spi_master device @@ -1188,124 +1305,140 @@ err_init_queue: */ static void of_register_spi_devices(struct spi_master *master) { - struct spi_device *spi; struct device_node *nc; - int rc; - u32 value; if (!master->dev.of_node) return; - for_each_available_child_of_node(master->dev.of_node, nc) { - /* Alloc an spi_device */ - spi = spi_alloc_device(master); - if (!spi) { - dev_err(&master->dev, "spi_device alloc error for %s\n", - nc->full_name); - spi_dev_put(spi); - continue; - } + for_each_available_child_of_node(master->dev.of_node, nc) + of_register_spi_device(master, nc); +} - /* Select device driver */ - if (of_modalias_node(nc, spi->modalias, - sizeof(spi->modalias)) < 0) { - dev_err(&master->dev, "cannot find modalias for %s\n", - nc->full_name); - spi_dev_put(spi); - continue; - } +static int of_dev_node_match(struct device *dev, void *data) +{ + return dev->of_node == data; +} - /* Device address */ - 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 = value; - - /* Mode (clock phase/polarity/etc.) */ - if (of_find_property(nc, "spi-cpha", NULL)) - spi->mode |= SPI_CPHA; - if (of_find_property(nc, "spi-cpol", NULL)) - spi->mode |= SPI_CPOL; - if (of_find_property(nc, "spi-cs-high", NULL)) - spi->mode |= SPI_CS_HIGH; - if (of_find_property(nc, "spi-3wire", NULL)) - spi->mode |= SPI_3WIRE; - - /* Device DUAL/QUAD mode */ - if (!of_property_read_u32(nc, "spi-tx-bus-width", &value)) { - switch (value) { - case 1: - break; - case 2: - spi->mode |= SPI_TX_DUAL; - break; - case 4: - spi->mode |= SPI_TX_QUAD; - break; - default: - dev_err(&master->dev, - "spi-tx-bus-width %d not supported\n", - value); - spi_dev_put(spi); - continue; - } - } +/* bah; the match functions differ just by const-ness */ +static int of_dev_node_match_const(struct device *dev, const void *data) +{ + return dev->of_node == data; +} - if (!of_property_read_u32(nc, "spi-rx-bus-width", &value)) { - switch (value) { - case 1: - break; - case 2: - spi->mode |= SPI_RX_DUAL; - break; - case 4: - spi->mode |= SPI_RX_QUAD; - break; - default: - dev_err(&master->dev, - "spi-rx-bus-width %d not supported\n", - value); - spi_dev_put(spi); - continue; - } - } +/* must call put_device() when done with returned spi_device device */ +struct spi_device *of_find_spi_device_by_node(struct device_node *node) +{ + struct device *dev; - /* Device speed */ - 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 = value; - - /* IRQ */ - spi->irq = irq_of_parse_and_map(nc, 0); - - /* Store a pointer to the node in the device structure */ - of_node_get(nc); - spi->dev.of_node = nc; - - /* Register the new device */ - 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", - nc->full_name); - spi_dev_put(spi); - } + dev = bus_find_device(&spi_bus_type, NULL, node, + of_dev_node_match); + if (!dev) + return NULL; + return to_spi_device(dev); +} +EXPORT_SYMBOL(of_find_spi_device_by_node); + +/* forward decl */ +static struct class spi_master_class; + +/* the spi masters are not using spi_bus, so we have to find it some other way */ +struct spi_master *of_find_spi_master_by_node(struct device_node *node) +{ + struct device *dev; + + dev = class_find_device(&spi_master_class, NULL, node, + of_dev_node_match_const); + if (!dev) + return NULL; + + /* reference got in class_find_device */ + return container_of(dev, struct spi_master, dev); +} +EXPORT_SYMBOL(of_find_spi_master_by_node); + +#ifdef CONFIG_OF_OVERLAY +static int spi_handler_create(struct of_overlay_device_entry *de, + int revert) +{ + struct device_node *dn; + struct spi_master *master; + struct spi_device *spi; + + if (!de || !de->np) + return -ENOTSUPP; + + dn = de->np; + + master = of_find_spi_master_by_node(dn->parent); + if (master == NULL) + return -ENOTSUPP; + + spi = of_register_spi_device(master, dn); + put_device(&master->dev); + + if (spi == NULL) { + pr_err("%s: failed to create spi device " + "for '%s'\n", + __func__, dn->full_name); + /* of_register_spi_device tosses the real error code */ + return -EINVAL; } + + return 0; } + +static int spi_handler_remove(struct of_overlay_device_entry *de, + int revert) +{ + struct device_node *dn; + struct spi_device *spi; + + if (!de || !de->np) + return -ENOTSUPP; + + dn = de->np; + + spi = of_find_spi_device_by_node(dn); + if (spi == NULL) + return -ENOTSUPP; + + /* unregister takes one ref away */ + spi_unregister_device(spi); + + /* and put the reference of the find */ + put_device(&spi->dev); + + return 0; +} + +static const struct of_overlay_handler_ops spi_handler_ops = { + .create = spi_handler_create, + .remove = spi_handler_remove, +}; + +static struct of_overlay_handler spi_handler = { + .name = "spi", + .ops = &spi_handler_ops, +}; + +static int __init spi_bus_handler_register(void) +{ + return of_overlay_handler_register(&spi_handler); +} +#endif + #else static void of_register_spi_devices(struct spi_master *master) { } #endif +#if !defined(CONFIG_OF) || !defined(CONFIG_OF_OVERLAY) +static inline int spi_bus_handler_register(void) +{ + return 0; +} +#endif + #ifdef CONFIG_ACPI static int acpi_spi_add_resource(struct acpi_resource *ares, void *data) { @@ -2270,8 +2403,14 @@ static int __init spi_init(void) status = class_register(&spi_master_class); if (status < 0) goto err2; - return 0; + status = spi_bus_handler_register(); + if (status < 0) + goto err3; + + return 0; +err3: + class_unregister(&spi_master_class); err2: bus_unregister(&spi_bus_type); err1: -- 1.7.12 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
