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author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-05 14:50:51 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-05 14:50:51 -0700 |
commit | 41844e36206be90cd4d962ea49b0abc3612a99d0 (patch) | |
tree | ce0b3a3403bc6abdb28f52779d0d7b57a51a5c86 /drivers/staging/greybus/fw-download.c | |
parent | 5691f0e9a3e7855832d5fd094801bf600347c2d0 (diff) | |
parent | fc1e2c8ea85e109acf09e74789e9b852f6eed251 (diff) | |
download | op-kernel-dev-41844e36206be90cd4d962ea49b0abc3612a99d0.zip op-kernel-dev-41844e36206be90cd4d962ea49b0abc3612a99d0.tar.gz |
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/fw-download.c')
-rw-r--r-- | drivers/staging/greybus/fw-download.c | 465 |
1 files changed, 465 insertions, 0 deletions
diff --git a/drivers/staging/greybus/fw-download.c b/drivers/staging/greybus/fw-download.c new file mode 100644 index 0000000..2d72468 --- /dev/null +++ b/drivers/staging/greybus/fw-download.c @@ -0,0 +1,465 @@ +/* + * Greybus Firmware Download Protocol Driver. + * + * Copyright 2016 Google Inc. + * Copyright 2016 Linaro Ltd. + * + * Released under the GPLv2 only. + */ + +#include <linux/firmware.h> +#include <linux/jiffies.h> +#include <linux/mutex.h> +#include <linux/workqueue.h> +#include "firmware.h" +#include "greybus.h" + +/* Estimated minimum buffer size, actual size can be smaller than this */ +#define MIN_FETCH_SIZE 512 +/* Timeout, in jiffies, within which fetch or release firmware must be called */ +#define NEXT_REQ_TIMEOUT_J msecs_to_jiffies(1000) + +struct fw_request { + u8 firmware_id; + bool disabled; + bool timedout; + char name[FW_NAME_SIZE]; + const struct firmware *fw; + struct list_head node; + + struct delayed_work dwork; + /* Timeout, in jiffies, within which the firmware shall download */ + unsigned long release_timeout_j; + struct kref kref; + struct fw_download *fw_download; +}; + +struct fw_download { + struct device *parent; + struct gb_connection *connection; + struct list_head fw_requests; + struct ida id_map; + struct mutex mutex; +}; + +static void fw_req_release(struct kref *kref) +{ + struct fw_request *fw_req = container_of(kref, struct fw_request, kref); + + dev_dbg(fw_req->fw_download->parent, "firmware %s released\n", + fw_req->name); + + release_firmware(fw_req->fw); + + /* + * The request timed out and the module may send a fetch-fw or + * release-fw request later. Lets block the id we allocated for this + * request, so that the AP doesn't refer to a later fw-request (with + * same firmware_id) for the old timedout fw-request. + * + * NOTE: + * + * This also means that after 255 timeouts we will fail to service new + * firmware downloads. But what else can we do in that case anyway? Lets + * just hope that it never happens. + */ + if (!fw_req->timedout) + ida_simple_remove(&fw_req->fw_download->id_map, + fw_req->firmware_id); + + kfree(fw_req); +} + +/* + * Incoming requests are serialized for a connection, and the only race possible + * is between the timeout handler freeing this and an incoming request. + * + * The operations on the fw-request list are protected by the mutex and + * get_fw_req() increments the reference count before returning a fw_req pointer + * to the users. + * + * free_firmware() also takes the mutex while removing an entry from the list, + * it guarantees that every user of fw_req has taken a kref-reference by now and + * we wouldn't have any new users. + * + * Once the last user drops the reference, the fw_req structure is freed. + */ +static void put_fw_req(struct fw_request *fw_req) +{ + kref_put(&fw_req->kref, fw_req_release); +} + +/* Caller must call put_fw_req() after using struct fw_request */ +static struct fw_request *get_fw_req(struct fw_download *fw_download, + u8 firmware_id) +{ + struct fw_request *fw_req; + + mutex_lock(&fw_download->mutex); + + list_for_each_entry(fw_req, &fw_download->fw_requests, node) { + if (fw_req->firmware_id == firmware_id) { + kref_get(&fw_req->kref); + goto unlock; + } + } + + fw_req = NULL; + +unlock: + mutex_unlock(&fw_download->mutex); + + return fw_req; +} + +static void free_firmware(struct fw_download *fw_download, + struct fw_request *fw_req) +{ + /* Already disabled from timeout handlers */ + if (fw_req->disabled) + return; + + mutex_lock(&fw_download->mutex); + list_del(&fw_req->node); + mutex_unlock(&fw_download->mutex); + + fw_req->disabled = true; + put_fw_req(fw_req); +} + +static void fw_request_timedout(struct work_struct *work) +{ + struct delayed_work *dwork = to_delayed_work(work); + struct fw_request *fw_req = container_of(dwork, struct fw_request, dwork); + struct fw_download *fw_download = fw_req->fw_download; + + dev_err(fw_download->parent, + "Timed out waiting for fetch / release firmware requests: %u\n", + fw_req->firmware_id); + + fw_req->timedout = true; + free_firmware(fw_download, fw_req); +} + +static int exceeds_release_timeout(struct fw_request *fw_req) +{ + struct fw_download *fw_download = fw_req->fw_download; + + if (time_before(jiffies, fw_req->release_timeout_j)) + return 0; + + dev_err(fw_download->parent, + "Firmware download didn't finish in time, abort: %d\n", + fw_req->firmware_id); + + fw_req->timedout = true; + free_firmware(fw_download, fw_req); + + return -ETIMEDOUT; +} + +/* This returns path of the firmware blob on the disk */ +static struct fw_request *find_firmware(struct fw_download *fw_download, + const char *tag) +{ + struct gb_interface *intf = fw_download->connection->bundle->intf; + struct fw_request *fw_req; + int ret, req_count; + + fw_req = kzalloc(sizeof(*fw_req), GFP_KERNEL); + if (!fw_req) + return ERR_PTR(-ENOMEM); + + /* Allocate ids from 1 to 255 (u8-max), 0 is an invalid id */ + ret = ida_simple_get(&fw_download->id_map, 1, 256, GFP_KERNEL); + if (ret < 0) { + dev_err(fw_download->parent, + "failed to allocate firmware id (%d)\n", ret); + goto err_free_req; + } + fw_req->firmware_id = ret; + + snprintf(fw_req->name, sizeof(fw_req->name), + FW_NAME_PREFIX "%08x_%08x_%08x_%08x_%s.tftf", + intf->ddbl1_manufacturer_id, intf->ddbl1_product_id, + intf->vendor_id, intf->product_id, tag); + + dev_info(fw_download->parent, "Requested firmware package '%s'\n", + fw_req->name); + + ret = request_firmware(&fw_req->fw, fw_req->name, fw_download->parent); + if (ret) { + dev_err(fw_download->parent, + "firmware request failed for %s (%d)\n", fw_req->name, + ret); + goto err_free_id; + } + + fw_req->fw_download = fw_download; + kref_init(&fw_req->kref); + + mutex_lock(&fw_download->mutex); + list_add(&fw_req->node, &fw_download->fw_requests); + mutex_unlock(&fw_download->mutex); + + /* Timeout, in jiffies, within which firmware should get loaded */ + req_count = DIV_ROUND_UP(fw_req->fw->size, MIN_FETCH_SIZE); + fw_req->release_timeout_j = jiffies + req_count * NEXT_REQ_TIMEOUT_J; + + INIT_DELAYED_WORK(&fw_req->dwork, fw_request_timedout); + schedule_delayed_work(&fw_req->dwork, NEXT_REQ_TIMEOUT_J); + + return fw_req; + +err_free_id: + ida_simple_remove(&fw_download->id_map, fw_req->firmware_id); +err_free_req: + kfree(fw_req); + + return ERR_PTR(ret); +} + +static int fw_download_find_firmware(struct gb_operation *op) +{ + struct gb_connection *connection = op->connection; + struct fw_download *fw_download = gb_connection_get_data(connection); + struct gb_fw_download_find_firmware_request *request; + struct gb_fw_download_find_firmware_response *response; + struct fw_request *fw_req; + const char *tag; + + if (op->request->payload_size != sizeof(*request)) { + dev_err(fw_download->parent, + "illegal size of find firmware request (%zu != %zu)\n", + op->request->payload_size, sizeof(*request)); + return -EINVAL; + } + + request = op->request->payload; + tag = (const char *)request->firmware_tag; + + /* firmware_tag must be null-terminated */ + if (strnlen(tag, GB_FIRMWARE_TAG_MAX_SIZE) == GB_FIRMWARE_TAG_MAX_SIZE) { + dev_err(fw_download->parent, + "firmware-tag is not null-terminated\n"); + return -EINVAL; + } + + fw_req = find_firmware(fw_download, tag); + if (IS_ERR(fw_req)) + return PTR_ERR(fw_req); + + if (!gb_operation_response_alloc(op, sizeof(*response), GFP_KERNEL)) { + dev_err(fw_download->parent, "error allocating response\n"); + free_firmware(fw_download, fw_req); + return -ENOMEM; + } + + response = op->response->payload; + response->firmware_id = fw_req->firmware_id; + response->size = cpu_to_le32(fw_req->fw->size); + + dev_dbg(fw_download->parent, + "firmware size is %zu bytes\n", fw_req->fw->size); + + return 0; +} + +static int fw_download_fetch_firmware(struct gb_operation *op) +{ + struct gb_connection *connection = op->connection; + struct fw_download *fw_download = gb_connection_get_data(connection); + struct gb_fw_download_fetch_firmware_request *request; + struct gb_fw_download_fetch_firmware_response *response; + struct fw_request *fw_req; + const struct firmware *fw; + unsigned int offset, size; + u8 firmware_id; + int ret = 0; + + if (op->request->payload_size != sizeof(*request)) { + dev_err(fw_download->parent, + "Illegal size of fetch firmware request (%zu %zu)\n", + op->request->payload_size, sizeof(*request)); + return -EINVAL; + } + + request = op->request->payload; + offset = le32_to_cpu(request->offset); + size = le32_to_cpu(request->size); + firmware_id = request->firmware_id; + + fw_req = get_fw_req(fw_download, firmware_id); + if (!fw_req) { + dev_err(fw_download->parent, + "firmware not available for id: %02u\n", firmware_id); + return -EINVAL; + } + + /* Make sure work handler isn't running in parallel */ + cancel_delayed_work_sync(&fw_req->dwork); + + /* We timed-out before reaching here ? */ + if (fw_req->disabled) { + ret = -ETIMEDOUT; + goto put_fw; + } + + /* + * Firmware download must finish within a limited time interval. If it + * doesn't, then we might have a buggy Module on the other side. Abort + * download. + */ + ret = exceeds_release_timeout(fw_req); + if (ret) + goto put_fw; + + fw = fw_req->fw; + + if (offset >= fw->size || size > fw->size - offset) { + dev_err(fw_download->parent, + "bad fetch firmware request (offs = %u, size = %u)\n", + offset, size); + ret = -EINVAL; + goto put_fw; + } + + if (!gb_operation_response_alloc(op, sizeof(*response) + size, + GFP_KERNEL)) { + dev_err(fw_download->parent, + "error allocating fetch firmware response\n"); + ret = -ENOMEM; + goto put_fw; + } + + response = op->response->payload; + memcpy(response->data, fw->data + offset, size); + + dev_dbg(fw_download->parent, + "responding with firmware (offs = %u, size = %u)\n", offset, + size); + + /* Refresh timeout */ + schedule_delayed_work(&fw_req->dwork, NEXT_REQ_TIMEOUT_J); + +put_fw: + put_fw_req(fw_req); + + return ret; +} + +static int fw_download_release_firmware(struct gb_operation *op) +{ + struct gb_connection *connection = op->connection; + struct fw_download *fw_download = gb_connection_get_data(connection); + struct gb_fw_download_release_firmware_request *request; + struct fw_request *fw_req; + u8 firmware_id; + + if (op->request->payload_size != sizeof(*request)) { + dev_err(fw_download->parent, + "Illegal size of release firmware request (%zu %zu)\n", + op->request->payload_size, sizeof(*request)); + return -EINVAL; + } + + request = op->request->payload; + firmware_id = request->firmware_id; + + fw_req = get_fw_req(fw_download, firmware_id); + if (!fw_req) { + dev_err(fw_download->parent, + "firmware not available for id: %02u\n", firmware_id); + return -EINVAL; + } + + cancel_delayed_work_sync(&fw_req->dwork); + + free_firmware(fw_download, fw_req); + put_fw_req(fw_req); + + dev_dbg(fw_download->parent, "release firmware\n"); + + return 0; +} + +int gb_fw_download_request_handler(struct gb_operation *op) +{ + u8 type = op->type; + + switch (type) { + case GB_FW_DOWNLOAD_TYPE_FIND_FIRMWARE: + return fw_download_find_firmware(op); + case GB_FW_DOWNLOAD_TYPE_FETCH_FIRMWARE: + return fw_download_fetch_firmware(op); + case GB_FW_DOWNLOAD_TYPE_RELEASE_FIRMWARE: + return fw_download_release_firmware(op); + default: + dev_err(&op->connection->bundle->dev, + "unsupported request: %u\n", type); + return -EINVAL; + } +} + +int gb_fw_download_connection_init(struct gb_connection *connection) +{ + struct fw_download *fw_download; + int ret; + + if (!connection) + return 0; + + fw_download = kzalloc(sizeof(*fw_download), GFP_KERNEL); + if (!fw_download) + return -ENOMEM; + + fw_download->parent = &connection->bundle->dev; + INIT_LIST_HEAD(&fw_download->fw_requests); + ida_init(&fw_download->id_map); + gb_connection_set_data(connection, fw_download); + fw_download->connection = connection; + mutex_init(&fw_download->mutex); + + ret = gb_connection_enable(connection); + if (ret) + goto err_destroy_id_map; + + return 0; + +err_destroy_id_map: + ida_destroy(&fw_download->id_map); + kfree(fw_download); + + return ret; +} + +void gb_fw_download_connection_exit(struct gb_connection *connection) +{ + struct fw_download *fw_download; + struct fw_request *fw_req, *tmp; + + if (!connection) + return; + + fw_download = gb_connection_get_data(connection); + gb_connection_disable(fw_download->connection); + + /* + * Make sure we have a reference to the pending requests, before they + * are freed from the timeout handler. + */ + mutex_lock(&fw_download->mutex); + list_for_each_entry(fw_req, &fw_download->fw_requests, node) + kref_get(&fw_req->kref); + mutex_unlock(&fw_download->mutex); + + /* Release pending firmware packages */ + list_for_each_entry_safe(fw_req, tmp, &fw_download->fw_requests, node) { + cancel_delayed_work_sync(&fw_req->dwork); + free_firmware(fw_download, fw_req); + put_fw_req(fw_req); + } + + ida_destroy(&fw_download->id_map); + kfree(fw_download); +} |