summaryrefslogtreecommitdiff
path: root/drivers/staging/greybus/hd.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2016-10-05 14:50:51 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-10-05 14:50:51 -0700
commit41844e36206be90cd4d962ea49b0abc3612a99d0 (patch)
treece0b3a3403bc6abdb28f52779d0d7b57a51a5c86 /drivers/staging/greybus/hd.c
parent5691f0e9a3e7855832d5fd094801bf600347c2d0 (diff)
parentfc1e2c8ea85e109acf09e74789e9b852f6eed251 (diff)
Merge tag 'staging-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging and IIO updates from Greg KH: "Here is the big staging and IIO driver pull request for 4.9-rc1. There are a lot of patches in here, the majority due to the drivers/staging/greybus/ subsystem being merged in with full development history that went back a few years, in order to preserve the work that those developers did over time. Lots and lots of tiny cleanups happened in the tree as well, due to the Outreachy application process and lots of other developers showing up for the first time to clean code up. Along with those changes, we deleted a wireless driver, and added a raspberrypi driver (currently marked broken), and lots of new iio drivers. Overall the tree still shrunk with more lines removed than added, about 10 thousand lines removed in total. Full details are in the very long shortlog below. All of this has been in the linux-next tree with no issues. There will be some merge problems with other subsystem trees, but those are all minor problems and shouldn't be hard to work out when they happen (MAINTAINERS and some lustre build problems with the IB tree)" And furter from me asking for clarification about greybus: "Right now there is a phone from Motorola shipping with this code (a slightly older version, but the same tree), so even though Ara is not alive in the same form, the functionality is happening. We are working with the developers of that phone to merge the newer stuff in with their fork so they can use the upstream version in future versions of their phone product line. Toshiba has at least one chip shipping in their catalog that needs/uses this protocol over a Unipro link, and rumor has it that there might be more in the future. There are also other users of the greybus protocols, there is a talk next week at ELC that shows how it is being used across a network connection to control a device, and previous ELC talks have showed the protocol stack being used over USB to drive embedded Linux boards. I've also talked to some people who are starting to work to add a host controller driver to control arduinos as the greybus PHY protocols are very useful to control a serial/i2c/spio/whatever device across a random physical link, as it is a way to have a self-describing device be attached to a host without needing manual configuration. So yes, people are using it, and there is still the chance that it will show up in a phone/laptop/tablet/whatever from Google in the future as well, the tech isn't dead, even if the original large phone project happens to be" * tag 'staging-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (3703 commits) Staging: fbtft: Fix bug in fbtft-core staging: rtl8188eu: fix double unlock error in rtw_resume_process() staging:r8188eu: remove GEN_MLME_EXT_HANDLER macro staging:r8188eu: remove GEN_DRV_CMD_HANDLER macro staging:r8188eu: remove GEN_EVT_CODE macro staging:r8188eu: remove GEN_CMD_CODE macro staging:r8188eu: remove pkt_newalloc member of the recv_buf structure staging:r8188eu: remove rtw_handle_dualmac declaration staging:r8188eu: remove (RGTRY|BSSID)_(OFT|SZ) macros staging:r8188eu: change rtl8188e_process_phy_info function argument type Staging: fsl-mc: Remove blank lines Staging: fsl-mc: Fix unaligned * in block comments Staging: comedi: Align the * in block comments Staging : ks7010 : Fix block comments warninig Staging: vt6655: Remove explicit NULL comparison using Coccinelle staging: rtl8188eu: core: rtw_xmit: Use macros instead of constants staging: rtl8188eu: core: rtw_xmit: Move constant of the right side staging: dgnc: Fix lines longer than 80 characters Staging: dgnc: constify attribute_group structures Staging: most: hdm-dim2: constify attribute_group structures ...
Diffstat (limited to 'drivers/staging/greybus/hd.c')
-rw-r--r--drivers/staging/greybus/hd.c257
1 files changed, 257 insertions, 0 deletions
diff --git a/drivers/staging/greybus/hd.c b/drivers/staging/greybus/hd.c
new file mode 100644
index 000000000000..185ae3fa10fd
--- /dev/null
+++ b/drivers/staging/greybus/hd.c
@@ -0,0 +1,257 @@
+/*
+ * Greybus Host Device
+ *
+ * Copyright 2014-2015 Google Inc.
+ * Copyright 2014-2015 Linaro Ltd.
+ *
+ * Released under the GPLv2 only.
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+
+#include "greybus.h"
+#include "greybus_trace.h"
+
+EXPORT_TRACEPOINT_SYMBOL_GPL(gb_hd_create);
+EXPORT_TRACEPOINT_SYMBOL_GPL(gb_hd_release);
+EXPORT_TRACEPOINT_SYMBOL_GPL(gb_hd_add);
+EXPORT_TRACEPOINT_SYMBOL_GPL(gb_hd_del);
+EXPORT_TRACEPOINT_SYMBOL_GPL(gb_hd_in);
+EXPORT_TRACEPOINT_SYMBOL_GPL(gb_message_submit);
+
+static struct ida gb_hd_bus_id_map;
+
+int gb_hd_output(struct gb_host_device *hd, void *req, u16 size, u8 cmd,
+ bool async)
+{
+ if (!hd || !hd->driver || !hd->driver->output)
+ return -EINVAL;
+ return hd->driver->output(hd, req, size, cmd, async);
+}
+EXPORT_SYMBOL_GPL(gb_hd_output);
+
+static ssize_t bus_id_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct gb_host_device *hd = to_gb_host_device(dev);
+
+ return sprintf(buf, "%d\n", hd->bus_id);
+}
+static DEVICE_ATTR_RO(bus_id);
+
+static struct attribute *bus_attrs[] = {
+ &dev_attr_bus_id.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(bus);
+
+int gb_hd_cport_reserve(struct gb_host_device *hd, u16 cport_id)
+{
+ struct ida *id_map = &hd->cport_id_map;
+ int ret;
+
+ ret = ida_simple_get(id_map, cport_id, cport_id + 1, GFP_KERNEL);
+ if (ret < 0) {
+ dev_err(&hd->dev, "failed to reserve cport %u\n", cport_id);
+ return ret;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(gb_hd_cport_reserve);
+
+void gb_hd_cport_release_reserved(struct gb_host_device *hd, u16 cport_id)
+{
+ struct ida *id_map = &hd->cport_id_map;
+
+ ida_simple_remove(id_map, cport_id);
+}
+EXPORT_SYMBOL_GPL(gb_hd_cport_release_reserved);
+
+/* Locking: Caller guarantees serialisation */
+int gb_hd_cport_allocate(struct gb_host_device *hd, int cport_id,
+ unsigned long flags)
+{
+ struct ida *id_map = &hd->cport_id_map;
+ int ida_start, ida_end;
+
+ if (hd->driver->cport_allocate)
+ return hd->driver->cport_allocate(hd, cport_id, flags);
+
+ if (cport_id < 0) {
+ ida_start = 0;
+ ida_end = hd->num_cports;
+ } else if (cport_id < hd->num_cports) {
+ ida_start = cport_id;
+ ida_end = cport_id + 1;
+ } else {
+ dev_err(&hd->dev, "cport %d not available\n", cport_id);
+ return -EINVAL;
+ }
+
+ return ida_simple_get(id_map, ida_start, ida_end, GFP_KERNEL);
+}
+
+/* Locking: Caller guarantees serialisation */
+void gb_hd_cport_release(struct gb_host_device *hd, u16 cport_id)
+{
+ if (hd->driver->cport_release) {
+ hd->driver->cport_release(hd, cport_id);
+ return;
+ }
+
+ ida_simple_remove(&hd->cport_id_map, cport_id);
+}
+
+static void gb_hd_release(struct device *dev)
+{
+ struct gb_host_device *hd = to_gb_host_device(dev);
+
+ trace_gb_hd_release(hd);
+
+ if (hd->svc)
+ gb_svc_put(hd->svc);
+ ida_simple_remove(&gb_hd_bus_id_map, hd->bus_id);
+ ida_destroy(&hd->cport_id_map);
+ kfree(hd);
+}
+
+struct device_type greybus_hd_type = {
+ .name = "greybus_host_device",
+ .release = gb_hd_release,
+};
+
+struct gb_host_device *gb_hd_create(struct gb_hd_driver *driver,
+ struct device *parent,
+ size_t buffer_size_max,
+ size_t num_cports)
+{
+ struct gb_host_device *hd;
+ int ret;
+
+ /*
+ * Validate that the driver implements all of the callbacks
+ * so that we don't have to every time we make them.
+ */
+ if ((!driver->message_send) || (!driver->message_cancel)) {
+ dev_err(parent, "mandatory hd-callbacks missing\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (buffer_size_max < GB_OPERATION_MESSAGE_SIZE_MIN) {
+ dev_err(parent, "greybus host-device buffers too small\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (num_cports == 0 || num_cports > CPORT_ID_MAX + 1) {
+ dev_err(parent, "Invalid number of CPorts: %zu\n", num_cports);
+ return ERR_PTR(-EINVAL);
+ }
+
+ /*
+ * Make sure to never allocate messages larger than what the Greybus
+ * protocol supports.
+ */
+ if (buffer_size_max > GB_OPERATION_MESSAGE_SIZE_MAX) {
+ dev_warn(parent, "limiting buffer size to %u\n",
+ GB_OPERATION_MESSAGE_SIZE_MAX);
+ buffer_size_max = GB_OPERATION_MESSAGE_SIZE_MAX;
+ }
+
+ hd = kzalloc(sizeof(*hd) + driver->hd_priv_size, GFP_KERNEL);
+ if (!hd)
+ return ERR_PTR(-ENOMEM);
+
+ ret = ida_simple_get(&gb_hd_bus_id_map, 1, 0, GFP_KERNEL);
+ if (ret < 0) {
+ kfree(hd);
+ return ERR_PTR(ret);
+ }
+ hd->bus_id = ret;
+
+ hd->driver = driver;
+ INIT_LIST_HEAD(&hd->modules);
+ INIT_LIST_HEAD(&hd->connections);
+ ida_init(&hd->cport_id_map);
+ hd->buffer_size_max = buffer_size_max;
+ hd->num_cports = num_cports;
+
+ hd->dev.parent = parent;
+ hd->dev.bus = &greybus_bus_type;
+ hd->dev.type = &greybus_hd_type;
+ hd->dev.groups = bus_groups;
+ hd->dev.dma_mask = hd->dev.parent->dma_mask;
+ device_initialize(&hd->dev);
+ dev_set_name(&hd->dev, "greybus%d", hd->bus_id);
+
+ trace_gb_hd_create(hd);
+
+ hd->svc = gb_svc_create(hd);
+ if (!hd->svc) {
+ dev_err(&hd->dev, "failed to create svc\n");
+ put_device(&hd->dev);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ return hd;
+}
+EXPORT_SYMBOL_GPL(gb_hd_create);
+
+int gb_hd_add(struct gb_host_device *hd)
+{
+ int ret;
+
+ ret = device_add(&hd->dev);
+ if (ret)
+ return ret;
+
+ ret = gb_svc_add(hd->svc);
+ if (ret) {
+ device_del(&hd->dev);
+ return ret;
+ }
+
+ trace_gb_hd_add(hd);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(gb_hd_add);
+
+void gb_hd_del(struct gb_host_device *hd)
+{
+ trace_gb_hd_del(hd);
+
+ /*
+ * Tear down the svc and flush any on-going hotplug processing before
+ * removing the remaining interfaces.
+ */
+ gb_svc_del(hd->svc);
+
+ device_del(&hd->dev);
+}
+EXPORT_SYMBOL_GPL(gb_hd_del);
+
+void gb_hd_shutdown(struct gb_host_device *hd)
+{
+ gb_svc_del(hd->svc);
+}
+EXPORT_SYMBOL_GPL(gb_hd_shutdown);
+
+void gb_hd_put(struct gb_host_device *hd)
+{
+ put_device(&hd->dev);
+}
+EXPORT_SYMBOL_GPL(gb_hd_put);
+
+int __init gb_hd_init(void)
+{
+ ida_init(&gb_hd_bus_id_map);
+
+ return 0;
+}
+
+void gb_hd_exit(void)
+{
+ ida_destroy(&gb_hd_bus_id_map);
+}