From aff5e3f89a0b07e7edf9243f913378cc27e4110d Mon Sep 17 00:00:00 2001 From: Pantelis Antoniou Date: Wed, 29 Oct 2014 10:40:37 +0200 Subject: spi/of: Create new device registration method and accessors Dynamically inserting spi device nodes requires the use of a single device registration method. Refactor the existing of_register_spi_devices() to split out the core functionality for a single device into a separate function; of_register_spi_device(). This function will be used by the OF_DYNAMIC overlay code to make live modifications to the tree. Methods to lookup a device/master using a device node are added as well, of_find_spi_master_by_node() & of_find_spi_device_by_node(). Signed-off-by: Pantelis Antoniou [grant.likely] Split patch into two pieces for clarity Signed-off-by: Grant Likely Reviewed-by: Mark Brown Cc: --- drivers/spi/spi.c | 222 +++++++++++++++++++++++++++++------------------------- 1 file changed, 118 insertions(+), 104 deletions(-) (limited to 'drivers/spi/spi.c') diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index ebcb33df2eb2..a3557c57d4f7 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1220,6 +1220,121 @@ err_init_queue: /*-------------------------------------------------------------------------*/ #if defined(CONFIG_OF) +static struct spi_device * +of_register_spi_device(struct spi_master *master, struct device_node *nc) +{ + struct spi_device *spi; + int rc; + 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); + rc = -ENOMEM; + goto err_out; + } + + /* Select device driver */ + rc = of_modalias_node(nc, spi->modalias, + sizeof(spi->modalias)); + if (rc < 0) { + dev_err(&master->dev, "cannot find modalias for %s\n", + nc->full_name); + goto err_out; + } + + /* 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); + 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; + if (of_find_property(nc, "spi-lsb-first", NULL)) + spi->mode |= SPI_LSB_FIRST; + + /* 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_warn(&master->dev, + "spi-tx-bus-width %d not supported\n", + value); + break; + } + } + + 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_warn(&master->dev, + "spi-rx-bus-width %d not supported\n", + value); + break; + } + } + + /* 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); + 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); + rc = spi_add_device(spi); + if (rc) { + 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(rc); +} + /** * of_register_spi_devices() - Register child devices onto the SPI bus * @master: Pointer to spi_master device @@ -1231,116 +1346,15 @@ 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", + spi = of_register_spi_device(master, nc); + if (IS_ERR(spi)) + dev_warn(&master->dev, "Failed to create SPI device for %s\n", nc->full_name); - spi_dev_put(spi); - continue; - } - - /* 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; - } - - /* 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; - if (of_find_property(nc, "spi-lsb-first", NULL)) - spi->mode |= SPI_LSB_FIRST; - - /* 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_warn(&master->dev, - "spi-tx-bus-width %d not supported\n", - value); - break; - } - } - - 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_warn(&master->dev, - "spi-rx-bus-width %d not supported\n", - value); - break; - } - } - - /* 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); - } - } } #else -- cgit v1.2.3 From ce79d54ae447d65117303ca9f61ffe9dcbc2465d Mon Sep 17 00:00:00 2001 From: Pantelis Antoniou Date: Tue, 28 Oct 2014 22:36:05 +0200 Subject: spi/of: Add OF notifier handler Add OF notifier handler needed for creating/destroying spi devices according to dynamic runtime changes in the DT live tree. This code is enabled when CONFIG_OF_DYNAMIC is selected. Signed-off-by: Pantelis Antoniou Signed-off-by: Grant Likely Reviewed-by: Mark Brown Cc: --- drivers/spi/spi.c | 84 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 84 insertions(+) (limited to 'drivers/spi/spi.c') diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index a3557c57d4f7..bf1cab0fad66 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -2317,6 +2317,86 @@ EXPORT_SYMBOL_GPL(spi_write_then_read); /*-------------------------------------------------------------------------*/ +#if IS_ENABLED(CONFIG_OF_DYNAMIC) +static int __spi_of_device_match(struct device *dev, void *data) +{ + return dev->of_node == data; +} + +/* must call put_device() when done with returned spi_device device */ +static struct spi_device *of_find_spi_device_by_node(struct device_node *node) +{ + struct device *dev = bus_find_device(&spi_bus_type, NULL, node, + __spi_of_device_match); + return dev ? to_spi_device(dev) : NULL; +} + +static int __spi_of_master_match(struct device *dev, const void *data) +{ + return dev->of_node == data; +} + +/* the spi masters are not using spi_bus, so we find it with another way */ +static 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, + __spi_of_master_match); + if (!dev) + return NULL; + + /* reference got in class_find_device */ + return container_of(dev, struct spi_master, dev); +} + +static int of_spi_notify(struct notifier_block *nb, unsigned long action, + void *arg) +{ + struct of_reconfig_data *rd = arg; + struct spi_master *master; + struct spi_device *spi; + + switch (of_reconfig_get_state_change(action, arg)) { + case OF_RECONFIG_CHANGE_ADD: + master = of_find_spi_master_by_node(rd->dn->parent); + if (master == NULL) + return NOTIFY_OK; /* not for us */ + + spi = of_register_spi_device(master, rd->dn); + put_device(&master->dev); + + if (IS_ERR(spi)) { + pr_err("%s: failed to create for '%s'\n", + __func__, rd->dn->full_name); + return notifier_from_errno(PTR_ERR(spi)); + } + break; + + case OF_RECONFIG_CHANGE_REMOVE: + /* find our device by node */ + spi = of_find_spi_device_by_node(rd->dn); + if (spi == NULL) + return NOTIFY_OK; /* no? not meant for us */ + + /* unregister takes one ref away */ + spi_unregister_device(spi); + + /* and put the reference of the find */ + put_device(&spi->dev); + break; + } + + return NOTIFY_OK; +} + +static struct notifier_block spi_of_notifier = { + .notifier_call = of_spi_notify, +}; +#else /* IS_ENABLED(CONFIG_OF_DYNAMIC) */ +extern struct notifier_block spi_of_notifier; +#endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */ + static int __init spi_init(void) { int status; @@ -2334,6 +2414,10 @@ static int __init spi_init(void) status = class_register(&spi_master_class); if (status < 0) goto err2; + + if (IS_ENABLED(CONFIG_OF)) + WARN_ON(of_reconfig_notifier_register(&spi_of_notifier)); + return 0; err2: -- cgit v1.2.3 From 5267720e7515f0fadf4cdef68dccafc18d48c806 Mon Sep 17 00:00:00 2001 From: Fabio Estevam Date: Wed, 26 Nov 2014 20:13:57 -0200 Subject: spi: Check for spi_of_notifier when CONFIG_OF_DYNAMIC=y Since commit ce79d54ae447d651173 ("spi/of: Add OF notifier handler") the following warning is seen on a imx53 system that has CONFIG_OF_DYNAMIC=n: [ 0.048119] ------------[ cut here ]------------ [ 0.048146] WARNING: CPU: 0 PID: 1 at drivers/spi/spi.c:2419 spi_init+0x60/0xa8() [ 0.048158] Modules linked in: [ 0.048183] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.18.0-rc6-next-20141126-00003-g9388e85 #2080 [ 0.048193] Hardware name: Freescale i.MX53 (Device Tree Support) [ 0.048203] Backtrace: [ 0.048235] [<80011f74>] (dump_backtrace) from [<80012110>] (show_stack+0x18/0x1c) [ 0.048246] r6:00000973 r5:00000000 r4:00000000 r3:00000000 [ 0.048284] [<800120f8>] (show_stack) from [<806b3ad8>] (dump_stack+0x88/0xa4) [ 0.048312] [<806b3a50>] (dump_stack) from [<8002a55c>] (warn_slowpath_common+0x80/0xbc) [ 0.048320] r5:8096cfcc r4:00000000 [ 0.048343] [<8002a4dc>] (warn_slowpath_common) from [<8002a5bc>] (warn_slowpath_null+0x24/0x2c) [ 0.048354] r8:8096cf6c r7:809355ec r6:ddcd7c00 r5:812029e4 r4:00000000 [ 0.048389] [<8002a598>] (warn_slowpath_null) from [<8096cfcc>] (spi_init+0x60/0xa8) [ 0.048405] [<8096cf6c>] (spi_init) from [<80008a7c>] (do_one_initcall+0x88/0x1e0) [ 0.048415] r5:8099e018 r4:8099e018 [ 0.048438] [<800089f4>] (do_one_initcall) from [<80935e38>] (kernel_init_freeable+0x110/0x1e0) [ 0.048448] r10:80980700 r9:809806e4 r8:000000cc r7:809355ec r6:809f8940 r5:00000002 [ 0.048478] r4:8098d744 [ 0.048508] [<80935d28>] (kernel_init_freeable) from [<806ae574>] (kernel_init+0x10/0xf4) [ 0.048517] r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:806ae564 [ 0.048547] r4:00000000 [ 0.048565] [<806ae564>] (kernel_init) from [<8000ed68>] (ret_from_fork+0x14/0x2c) [ 0.048574] r4:00000000 r3:00000000 [ 0.048616] ---[ end trace 405a65d177dae4fd ]--- Only check of_reconfig_notifier_register() in the CONFIG_OF_DYNAMIC=y case, as intended by commit ce79d54ae447d65. Signed-off-by: Fabio Estevam Signed-off-by: Grant Likely --- drivers/spi/spi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/spi/spi.c') diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index bf1cab0fad66..cf4ed29c7ee6 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -2415,7 +2415,7 @@ static int __init spi_init(void) if (status < 0) goto err2; - if (IS_ENABLED(CONFIG_OF)) + if (IS_ENABLED(CONFIG_OF_DYNAMIC)) WARN_ON(of_reconfig_notifier_register(&spi_of_notifier)); return 0; -- cgit v1.2.3