diff options
Diffstat (limited to 'drivers/usb/wusbcore/mmc.c')
| -rw-r--r-- | drivers/usb/wusbcore/mmc.c | 329 |
1 files changed, 329 insertions, 0 deletions
diff --git a/drivers/usb/wusbcore/mmc.c b/drivers/usb/wusbcore/mmc.c new file mode 100644 index 000000000000..e5390b77aaaa --- /dev/null +++ b/drivers/usb/wusbcore/mmc.c @@ -0,0 +1,329 @@ +/* + * WUSB Wire Adapter: Control/Data Streaming Interface (WUSB[8]) + * MMC (Microscheduled Management Command) handling + * + * Copyright (C) 2005-2006 Intel Corporation + * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + * + * + * WUIEs and MMC IEs...well, they are almost the same at the end. MMC + * IEs are Wireless USB IEs that go into the MMC period...[what is + * that? look in Design-overview.txt]. + * + * + * This is a simple subsystem to keep track of which IEs are being + * sent by the host in the MMC period. + * + * For each WUIE we ask to send, we keep it in an array, so we can + * request its removal later, or replace the content. They are tracked + * by pointer, so be sure to use the same pointer if you want to + * remove it or update the contents. + * + * FIXME: + * - add timers that autoremove intervalled IEs? + */ +#include <linux/usb/wusb.h> +#include "wusbhc.h" + +/* Initialize the MMCIEs handling mechanism */ +int wusbhc_mmcie_create(struct wusbhc *wusbhc) +{ + u8 mmcies = wusbhc->mmcies_max; + wusbhc->mmcie = kzalloc(mmcies * sizeof(wusbhc->mmcie[0]), GFP_KERNEL); + if (wusbhc->mmcie == NULL) + return -ENOMEM; + mutex_init(&wusbhc->mmcie_mutex); + return 0; +} + +/* Release resources used by the MMCIEs handling mechanism */ +void wusbhc_mmcie_destroy(struct wusbhc *wusbhc) +{ + kfree(wusbhc->mmcie); +} + +/* + * Add or replace an MMC Wireless USB IE. + * + * @interval: See WUSB1.0[8.5.3.1] + * @repeat_cnt: See WUSB1.0[8.5.3.1] + * @handle: See WUSB1.0[8.5.3.1] + * @wuie: Pointer to the header of the WUSB IE data to add. + * MUST BE allocated in a kmalloc buffer (no stack or + * vmalloc). + * THE CALLER ALWAYS OWNS THE POINTER (we don't free it + * on remove, we just forget about it). + * @returns: 0 if ok, < 0 errno code on error. + * + * Goes over the *whole* @wusbhc->mmcie array looking for (a) the + * first free spot and (b) if @wuie is already in the array (aka: + * transmitted in the MMCs) the spot were it is. + * + * If present, we "overwrite it" (update). + * + * + * NOTE: Need special ordering rules -- see below WUSB1.0 Table 7-38. + * The host uses the handle as the 'sort' index. We + * allocate the last one always for the WUIE_ID_HOST_INFO, and + * the rest, first come first serve in inverse order. + * + * Host software must make sure that it adds the other IEs in + * the right order... the host hardware is responsible for + * placing the WCTA IEs in the right place with the other IEs + * set by host software. + * + * NOTE: we can access wusbhc->wa_descr without locking because it is + * read only. + */ +int wusbhc_mmcie_set(struct wusbhc *wusbhc, u8 interval, u8 repeat_cnt, + struct wuie_hdr *wuie) +{ + int result = -ENOBUFS; + struct device *dev = wusbhc->dev; + unsigned handle, itr; + + /* Search a handle, taking into account the ordering */ + mutex_lock(&wusbhc->mmcie_mutex); + switch (wuie->bIEIdentifier) { + case WUIE_ID_HOST_INFO: + /* Always last */ + handle = wusbhc->mmcies_max - 1; + break; + case WUIE_ID_ISOCH_DISCARD: + dev_err(wusbhc->dev, "Special ordering case for WUIE ID 0x%x " + "unimplemented\n", wuie->bIEIdentifier); + result = -ENOSYS; + goto error_unlock; + default: + /* search for it or find the last empty slot */ + handle = ~0; + for (itr = 0; itr < wusbhc->mmcies_max - 1; itr++) { + if (wusbhc->mmcie[itr] == wuie) { + handle = itr; + break; + } + if (wusbhc->mmcie[itr] == NULL) + handle = itr; + } + if (handle == ~0) { + if (printk_ratelimit()) + dev_err(dev, "MMC handle space exhausted\n"); + goto error_unlock; + } + } + result = (wusbhc->mmcie_add)(wusbhc, interval, repeat_cnt, handle, + wuie); + if (result >= 0) + wusbhc->mmcie[handle] = wuie; +error_unlock: + mutex_unlock(&wusbhc->mmcie_mutex); + return result; +} +EXPORT_SYMBOL_GPL(wusbhc_mmcie_set); + +/* + * Remove an MMC IE previously added with wusbhc_mmcie_set() + * + * @wuie Pointer used to add the WUIE + */ +void wusbhc_mmcie_rm(struct wusbhc *wusbhc, struct wuie_hdr *wuie) +{ + int result; + struct device *dev = wusbhc->dev; + unsigned handle, itr; + + mutex_lock(&wusbhc->mmcie_mutex); + for (itr = 0; itr < wusbhc->mmcies_max; itr++) + if (wusbhc->mmcie[itr] == wuie) { + handle = itr; + goto found; + } + mutex_unlock(&wusbhc->mmcie_mutex); + return; + +found: + result = (wusbhc->mmcie_rm)(wusbhc, handle); + if (result == 0) + wusbhc->mmcie[itr] = NULL; + else if (printk_ratelimit()) + dev_err(dev, "MMC: Failed to remove IE %p (0x%02x)\n", + wuie, wuie->bIEIdentifier); + mutex_unlock(&wusbhc->mmcie_mutex); + return; +} +EXPORT_SYMBOL_GPL(wusbhc_mmcie_rm); + +/* + * wusbhc_start - start transmitting MMCs and accepting connections + * @wusbhc: the HC to start + * @chid: the CHID to use for this host + * + * Establishes a cluster reservation, enables device connections, and + * starts MMCs with appropriate DNTS parameters. + */ +int wusbhc_start(struct wusbhc *wusbhc, const struct wusb_ckhdid *chid) +{ + int result; + struct device *dev = wusbhc->dev; + + WARN_ON(wusbhc->wuie_host_info != NULL); + + result = wusbhc_rsv_establish(wusbhc); + if (result < 0) { + dev_err(dev, "cannot establish cluster reservation: %d\n", + result); + goto error_rsv_establish; + } + + result = wusbhc_devconnect_start(wusbhc, chid); + if (result < 0) { + dev_err(dev, "error enabling device connections: %d\n", result); + goto error_devconnect_start; + } + + result = wusbhc_sec_start(wusbhc); + if (result < 0) { + dev_err(dev, "error starting security in the HC: %d\n", result); + goto error_sec_start; + } + /* FIXME: the choice of the DNTS parameters is somewhat + * arbitrary */ + result = wusbhc->set_num_dnts(wusbhc, 0, 15); + if (result < 0) { + dev_err(dev, "Cannot set DNTS parameters: %d\n", result); + goto error_set_num_dnts; + } + result = wusbhc->start(wusbhc); + if (result < 0) { + dev_err(dev, "error starting wusbch: %d\n", result); + goto error_wusbhc_start; + } + wusbhc->active = 1; + return 0; + +error_wusbhc_start: + wusbhc_sec_stop(wusbhc); +error_set_num_dnts: +error_sec_start: + wusbhc_devconnect_stop(wusbhc); +error_devconnect_start: + wusbhc_rsv_terminate(wusbhc); +error_rsv_establish: + return result; +} + +/* + * Disconnect all from the WUSB Channel + * + * Send a Host Disconnect IE in the MMC, wait, don't send it any more + */ +static int __wusbhc_host_disconnect_ie(struct wusbhc *wusbhc) +{ + int result = -ENOMEM; + struct wuie_host_disconnect *host_disconnect_ie; + might_sleep(); + host_disconnect_ie = kmalloc(sizeof(*host_disconnect_ie), GFP_KERNEL); + if (host_disconnect_ie == NULL) + goto error_alloc; + host_disconnect_ie->hdr.bLength = sizeof(*host_disconnect_ie); + host_disconnect_ie->hdr.bIEIdentifier = WUIE_ID_HOST_DISCONNECT; + result = wusbhc_mmcie_set(wusbhc, 0, 0, &host_disconnect_ie->hdr); + if (result < 0) + goto error_mmcie_set; + + /* WUSB1.0[8.5.3.1 & 7.5.2] */ + msleep(100); + wusbhc_mmcie_rm(wusbhc, &host_disconnect_ie->hdr); +error_mmcie_set: + kfree(host_disconnect_ie); +error_alloc: + return result; +} + +/* + * wusbhc_stop - stop transmitting MMCs + * @wusbhc: the HC to stop + * + * Send a Host Disconnect IE, wait, remove all the MMCs (stop sending MMCs). + * + * If we can't allocate a Host Stop IE, screw it, we don't notify the + * devices we are disconnecting... + */ +void wusbhc_stop(struct wusbhc *wusbhc) +{ + if (wusbhc->active) { + wusbhc->active = 0; + wusbhc->stop(wusbhc); + wusbhc_sec_stop(wusbhc); + __wusbhc_host_disconnect_ie(wusbhc); + wusbhc_devconnect_stop(wusbhc); + wusbhc_rsv_terminate(wusbhc); + } +} +EXPORT_SYMBOL_GPL(wusbhc_stop); + +/* + * Change the CHID in a WUSB Channel + * + * If it is just a new CHID, send a Host Disconnect IE and then change + * the CHID IE. + */ +static int __wusbhc_chid_change(struct wusbhc *wusbhc, + const struct wusb_ckhdid *chid) +{ + int result = -ENOSYS; + struct device *dev = wusbhc->dev; + dev_err(dev, "%s() not implemented yet\n", __func__); + return result; + + BUG_ON(wusbhc->wuie_host_info == NULL); + __wusbhc_host_disconnect_ie(wusbhc); + wusbhc->wuie_host_info->CHID = *chid; + result = wusbhc_mmcie_set(wusbhc, 0, 0, &wusbhc->wuie_host_info->hdr); + if (result < 0) + dev_err(dev, "Can't update Host Info WUSB IE: %d\n", result); + return result; +} + +/* + * Set/reset/update a new CHID + * + * Depending on the previous state of the MMCs, start, stop or change + * the sent MMC. This effectively switches the host controller on and + * off (radio wise). + */ +int wusbhc_chid_set(struct wusbhc *wusbhc, const struct wusb_ckhdid *chid) +{ + int result = 0; + + if (memcmp(chid, &wusb_ckhdid_zero, sizeof(chid)) == 0) + chid = NULL; + + mutex_lock(&wusbhc->mutex); + if (wusbhc->active) { + if (chid) + result = __wusbhc_chid_change(wusbhc, chid); + else + wusbhc_stop(wusbhc); + } else { + if (chid) + wusbhc_start(wusbhc, chid); + } + mutex_unlock(&wusbhc->mutex); + return result; +} +EXPORT_SYMBOL_GPL(wusbhc_chid_set); |