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Message-Id: <dc178afb54a987c2f24bc4d8f800a2401c807afc.1229820957.git.inaky@linux.intel.com>
Date: Sat, 20 Dec 2008 16:57:51 -0800
From: Inaky Perez-Gonzalez <inaky@...ux.intel.com>
To: netdev@...r.kernel.org
Cc: wimax@...uxwimax.org, greg@...ah.com
Subject: [PATCH 20/29] i2400m/USB: probe/disconnect, dev init/shutdown and reset backends
Implements probe/disconnect for the USB device, as well as main
backends for the generic driver to control the USB device
(bus_dev_start(), bus_dev_stop() and bus_reset()).
Signed-off-by: Inaky Perez-Gonzalez <inaky@...ux.intel.com>
---
drivers/net/wimax/i2400m/usb.c | 591 ++++++++++++++++++++++++++++++++++++++++
1 files changed, 591 insertions(+), 0 deletions(-)
create mode 100644 drivers/net/wimax/i2400m/usb.c
diff --git a/drivers/net/wimax/i2400m/usb.c b/drivers/net/wimax/i2400m/usb.c
new file mode 100644
index 0000000..6d4b65f
--- /dev/null
+++ b/drivers/net/wimax/i2400m/usb.c
@@ -0,0 +1,591 @@
+/*
+ * Intel Wireless WiMAX Connection 2400m
+ * Linux driver model glue for USB device, reset & fw upload
+ *
+ *
+ * Copyright (C) 2007-2008 Intel Corporation <linux-wimax@...el.com>
+ * Inaky Perez-Gonzalez <inaky.perez-gonzalez@...el.com>
+ * Yanir Lubetkin <yanirx.lubetkin@...el.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.
+ *
+ *
+ * See i2400m-usb.h for a general description of this driver.
+ *
+ * This file implements driver model glue, and hook ups for the
+ * generic driver to implement the bus-specific functions (device
+ * communication setup/tear down, firmware upload and resetting).
+ *
+ * ROADMAP
+ *
+ * i2400mu_probe()
+ * alloc_netdev()...
+ * i2400mu_netdev_setup()
+ * i2400mu_init()
+ * i2400m_netdev_setup()
+ * i2400m_setup()...
+ *
+ * i2400mu_disconnect
+ * i2400m_release()
+ * free_netdev()
+ *
+ * i2400mu_suspend()
+ * i2400m_cmd_enter_powersave()
+ * i2400mu_notification_release()
+ *
+ * i2400mu_resume()
+ * i2400mu_notification_setup()
+ *
+ * i2400mu_bus_dev_start() Called by i2400m_dev_start() [who is
+ * i2400mu_tx_setup() called by i2400m_setup()]
+ * i2400mu_rx_setup()
+ * i2400mu_notification_setup()
+ *
+ * i2400mu_bus_dev_stop() Called by i2400m_dev_stop() [who is
+ * i2400mu_notification_release() called by i2400m_release()]
+ * i2400mu_rx_release()
+ * i2400mu_tx_release()
+ *
+ * i2400mu_bus_reset() Called by i2400m->bus_reset
+ * __i2400mu_reset()
+ * __i2400mu_send_barker()
+ * usb_reset_device()
+ */
+#include "i2400m-usb.h"
+#include <linux/wimax/i2400m.h>
+#include <linux/debugfs.h>
+
+
+#define D_SUBMODULE usb
+#include "usb-debug-levels.h"
+
+
+/* Our firmware file name */
+#define I2400MU_FW_FILE_NAME "i2400m-fw-usb-" I2400M_FW_VERSION ".sbcf"
+
+static
+int i2400mu_bus_dev_start(struct i2400m *i2400m)
+{
+ int result;
+ struct i2400mu *i2400mu = container_of(i2400m, struct i2400mu, i2400m);
+ struct device *dev = &i2400mu->usb_iface->dev;
+
+ d_fnstart(3, dev, "(i2400m %p)\n", i2400m);
+ result = i2400mu_tx_setup(i2400mu);
+ if (result < 0)
+ goto error_usb_tx_setup;
+ result = i2400mu_rx_setup(i2400mu);
+ if (result < 0)
+ goto error_usb_rx_setup;
+ result = i2400mu_notification_setup(i2400mu);
+ if (result < 0)
+ goto error_notif_setup;
+ d_fnend(3, dev, "(i2400m %p) = %d\n", i2400m, result);
+ return result;
+
+error_notif_setup:
+ i2400mu_rx_release(i2400mu);
+error_usb_rx_setup:
+ i2400mu_tx_release(i2400mu);
+error_usb_tx_setup:
+ d_fnend(3, dev, "(i2400m %p) = void\n", i2400m);
+ return result;
+}
+
+
+static
+void i2400mu_bus_dev_stop(struct i2400m *i2400m)
+{
+ struct i2400mu *i2400mu = container_of(i2400m, struct i2400mu, i2400m);
+ struct device *dev = &i2400mu->usb_iface->dev;
+
+ d_fnstart(3, dev, "(i2400m %p)\n", i2400m);
+ i2400mu_notification_release(i2400mu);
+ i2400mu_rx_release(i2400mu);
+ i2400mu_tx_release(i2400mu);
+ d_fnend(3, dev, "(i2400m %p) = void\n", i2400m);
+}
+
+
+/*
+ * Sends a barker buffer to the device
+ *
+ * This helper will allocate a kmalloced buffer and use it to transmit
+ * (then free it). Reason for this is that other arches cannot use
+ * stack/vmalloc/text areas for DMA transfers.
+ *
+ * Error recovery here is simpler: anything is considered a hard error
+ * and will move the reset code to use a last-resort bus-based reset.
+ */
+static
+int __i2400mu_send_barker(struct i2400mu *i2400mu,
+ const __le32 *barker,
+ size_t barker_size,
+ unsigned endpoint)
+{
+ struct usb_endpoint_descriptor *epd = NULL;
+ int pipe, actual_len, ret;
+ struct device *dev = &i2400mu->usb_iface->dev;
+ void *buffer;
+ int do_autopm = 1;
+
+ ret = usb_autopm_get_interface(i2400mu->usb_iface);
+ if (ret < 0) {
+ dev_err(dev, "RESET: can't get autopm: %d\n", ret);
+ do_autopm = 0;
+ }
+ ret = -ENOMEM;
+ buffer = kmalloc(barker_size, GFP_KERNEL);
+ if (buffer == NULL)
+ goto error_kzalloc;
+ epd = usb_get_epd(i2400mu->usb_iface, endpoint);
+ pipe = usb_sndbulkpipe(i2400mu->usb_dev, epd->bEndpointAddress);
+ memcpy(buffer, barker, barker_size);
+ ret = usb_bulk_msg(i2400mu->usb_dev, pipe, buffer, barker_size,
+ &actual_len, HZ);
+ if (ret < 0) {
+ if (ret != -EINVAL)
+ dev_err(dev, "E: barker error: %d\n", ret);
+ } else if (actual_len != barker_size) {
+ dev_err(dev, "E: only %d bytes transmitted\n", actual_len);
+ ret = -EIO;
+ }
+ kfree(buffer);
+error_kzalloc:
+ if (do_autopm)
+ usb_autopm_put_interface(i2400mu->usb_iface);
+ return ret;
+}
+
+
+/*
+ * Reset a device at different levels (warm, cold or bus)
+ *
+ * @i2400m: device descriptor
+ * @reset_type: soft, warm or bus reset (I2400M_RT_WARM/SOFT/BUS)
+ *
+ * Warm and cold resets get a USB reset if they fail.
+ *
+ * Warm reset:
+ *
+ * The device will be fully reset internally, but won't be
+ * disconnected from the USB bus (so no reenumeration will
+ * happen). Firmware upload will be neccessary.
+ *
+ * The device will send a reboot barker in the notification endpoint
+ * that will trigger the driver to reinitialize the state
+ * automatically from notif.c:i2400m_notification_grok() into
+ * i2400m_dev_bootstrap_delayed().
+ *
+ * Cold and bus (USB) reset:
+ *
+ * The device will be fully reset internally, disconnected from the
+ * USB bus an a reenumeration will happen. Firmware upload will be
+ * neccessary. Thus, we don't do any locking or struct
+ * reinitialization, as we are going to be fully disconnected and
+ * reenumerated.
+ *
+ * Note we need to return -ENODEV if a warm reset was requested and we
+ * had to resort to a bus reset. See i2400m_op_reset(), wimax_reset()
+ * and wimax_dev->op_reset.
+ *
+ * WARNING: no driver state saved/fixed
+ */
+static
+int i2400mu_bus_reset(struct i2400m *i2400m, enum i2400m_reset_type rt)
+{
+ int result;
+ struct i2400mu *i2400mu =
+ container_of(i2400m, struct i2400mu, i2400m);
+ struct device *dev = i2400m_dev(i2400m);
+ static const __le32 i2400m_WARM_BOOT_BARKER[4] = {
+ __constant_cpu_to_le32(I2400M_WARM_RESET_BARKER),
+ __constant_cpu_to_le32(I2400M_WARM_RESET_BARKER),
+ __constant_cpu_to_le32(I2400M_WARM_RESET_BARKER),
+ __constant_cpu_to_le32(I2400M_WARM_RESET_BARKER),
+ };
+ static const __le32 i2400m_COLD_BOOT_BARKER[4] = {
+ __constant_cpu_to_le32(I2400M_COLD_RESET_BARKER),
+ __constant_cpu_to_le32(I2400M_COLD_RESET_BARKER),
+ __constant_cpu_to_le32(I2400M_COLD_RESET_BARKER),
+ __constant_cpu_to_le32(I2400M_COLD_RESET_BARKER),
+ };
+
+ d_fnstart(3, dev, "(i2400m %p rt %u)\n", i2400m, rt);
+ if (rt == I2400M_RT_WARM)
+ result = __i2400mu_send_barker(i2400mu, i2400m_WARM_BOOT_BARKER,
+ sizeof(i2400m_WARM_BOOT_BARKER),
+ I2400MU_EP_BULK_OUT);
+ else if (rt == I2400M_RT_COLD)
+ result = __i2400mu_send_barker(i2400mu, i2400m_COLD_BOOT_BARKER,
+ sizeof(i2400m_COLD_BOOT_BARKER),
+ I2400MU_EP_RESET_COLD);
+ else if (rt == I2400M_RT_BUS) {
+do_bus_reset:
+ result = usb_reset_device(i2400mu->usb_dev);
+ switch (result) {
+ case 0:
+ case -EINVAL: /* device is gone */
+ case -ENODEV:
+ case -ENOENT:
+ case -ESHUTDOWN:
+ result = rt == I2400M_RT_WARM ? -ENODEV : 0;
+ break; /* We assume the device is disconnected */
+ default:
+ dev_err(dev, "USB reset failed (%d), giving up!\n",
+ result);
+ }
+ } else
+ BUG();
+ if (result < 0
+ && result != -EINVAL /* device is gone */
+ && rt != I2400M_RT_BUS) {
+ dev_err(dev, "%s reset failed (%d); trying USB reset\n",
+ rt == I2400M_RT_WARM ? "warm" : "cold", result);
+ rt = I2400M_RT_BUS;
+ goto do_bus_reset;
+ }
+ d_fnend(3, dev, "(i2400m %p rt %u) = %d\n", i2400m, rt, result);
+ return result;
+}
+
+
+static
+void i2400mu_netdev_setup(struct net_device *net_dev)
+{
+ struct i2400m *i2400m = net_dev_to_i2400m(net_dev);
+ struct i2400mu *i2400mu = container_of(i2400m, struct i2400mu, i2400m);
+ i2400mu_init(i2400mu);
+ i2400m_netdev_setup(net_dev);
+}
+
+
+/*
+ * Debug levels control; see debug.h
+ */
+struct d_level D_LEVEL[] = {
+ D_SUBMODULE_DEFINE(usb),
+ D_SUBMODULE_DEFINE(fw),
+ D_SUBMODULE_DEFINE(notif),
+ D_SUBMODULE_DEFINE(rx),
+ D_SUBMODULE_DEFINE(tx),
+};
+size_t D_LEVEL_SIZE = ARRAY_SIZE(D_LEVEL);
+
+
+#define __debugfs_register(prefix, name, parent) \
+do { \
+ result = d_level_register_debugfs(prefix, name, parent); \
+ if (result < 0) \
+ goto error; \
+} while (0)
+
+
+static
+int i2400mu_debugfs_add(struct i2400mu *i2400mu)
+{
+ int result;
+ struct device *dev = &i2400mu->usb_iface->dev;
+ struct dentry *dentry = i2400mu->i2400m.wimax_dev.debugfs_dentry;
+ struct dentry *fd;
+
+ dentry = debugfs_create_dir("i2400m-usb", dentry);
+ result = PTR_ERR(dentry);
+ if (IS_ERR(dentry)) {
+ if (result == -ENODEV)
+ result = 0; /* No debugfs support */
+ goto error;
+ }
+ i2400mu->debugfs_dentry = dentry;
+ __debugfs_register("dl_", usb, dentry);
+ __debugfs_register("dl_", fw, dentry);
+ __debugfs_register("dl_", notif, dentry);
+ __debugfs_register("dl_", rx, dentry);
+ __debugfs_register("dl_", tx, dentry);
+
+ /* Don't touch these if you don't know what you are doing */
+ fd = debugfs_create_u8("rx_size_auto_shrink", 0600, dentry,
+ &i2400mu->rx_size_auto_shrink);
+ result = PTR_ERR(fd);
+ if (IS_ERR(fd) && result != -ENODEV) {
+ dev_err(dev, "Can't create debugfs entry "
+ "rx_size_auto_shrink: %d\n", result);
+ goto error;
+ }
+
+ fd = debugfs_create_size_t("rx_size", 0600, dentry,
+ &i2400mu->rx_size);
+ result = PTR_ERR(fd);
+ if (IS_ERR(fd) && result != -ENODEV) {
+ dev_err(dev, "Can't create debugfs entry "
+ "rx_size: %d\n", result);
+ goto error;
+ }
+
+ return 0;
+
+error:
+ debugfs_remove_recursive(i2400mu->debugfs_dentry);
+ return result;
+}
+
+
+/*
+ * Probe a i2400m interface and register it
+ *
+ * @iface: USB interface to link to
+ * @id: USB class/subclass/protocol id
+ * @returns: 0 if ok, < 0 errno code on error.
+ *
+ * Alloc a net device, initialize the bus-specific details and then
+ * calls the bus-generic initialization routine. That will register
+ * the wimax and netdev devices, upload the firmware [using
+ * _bus_bm_*()], call _bus_dev_start() to finalize the setup of the
+ * communication with the device and then will start to talk to it to
+ * finnish setting it up.
+ */
+static
+int i2400mu_probe(struct usb_interface *iface,
+ const struct usb_device_id *id)
+{
+ int result;
+ struct net_device *net_dev;
+ struct device *dev = &iface->dev;
+ struct i2400m *i2400m;
+ struct i2400mu *i2400mu;
+ struct usb_device *usb_dev = interface_to_usbdev(iface);
+
+ if (usb_dev->speed != USB_SPEED_HIGH)
+ dev_err(dev, "device not connected as high speed\n");
+
+ /* Allocate instance [calls i2400m_netdev_setup() on it]. */
+ result = -ENOMEM;
+ net_dev = alloc_netdev(sizeof(*i2400mu), "wmx%d",
+ i2400mu_netdev_setup);
+ if (net_dev == NULL) {
+ dev_err(dev, "no memory for network device instance\n");
+ goto error_alloc_netdev;
+ }
+ SET_NETDEV_DEV(net_dev, dev);
+ i2400m = net_dev_to_i2400m(net_dev);
+ i2400mu = container_of(i2400m, struct i2400mu, i2400m);
+ i2400m->wimax_dev.net_dev = net_dev;
+ i2400mu->usb_dev = usb_get_dev(usb_dev);
+ i2400mu->usb_iface = iface;
+ usb_set_intfdata(iface, i2400mu);
+
+ i2400m->bus_tx_block_size = I2400MU_BLK_SIZE;
+ i2400m->bus_pl_size_max = I2400MU_PL_SIZE_MAX;
+ i2400m->bus_dev_start = i2400mu_bus_dev_start;
+ i2400m->bus_dev_stop = i2400mu_bus_dev_stop;
+ i2400m->bus_tx_kick = i2400mu_bus_tx_kick;
+ i2400m->bus_reset = i2400mu_bus_reset;
+ i2400m->bus_bm_cmd_send = i2400mu_bus_bm_cmd_send;
+ i2400m->bus_bm_wait_for_ack = i2400mu_bus_bm_wait_for_ack;
+ i2400m->bus_fw_name = I2400MU_FW_FILE_NAME;
+ i2400m->bus_bm_mac_addr_impaired = 0;
+
+ iface->needs_remote_wakeup = 1; /* autosuspend (15s delay) */
+ device_init_wakeup(dev, 1);
+ usb_autopm_enable(i2400mu->usb_iface);
+ usb_dev->autosuspend_delay = 15 * HZ;
+ usb_dev->autosuspend_disabled = 0;
+
+ result = i2400m_setup(i2400m, I2400M_BRI_MAC_REINIT);
+ if (result < 0) {
+ dev_err(dev, "cannot setup device: %d\n", result);
+ goto error_setup;
+ }
+ result = i2400mu_debugfs_add(i2400mu);
+ if (result < 0) {
+ dev_err(dev, "Can't register i2400mu's debugfs: %d\n", result);
+ goto error_debugfs_add;
+ }
+ return 0;
+
+error_debugfs_add:
+ i2400m_release(i2400m);
+error_setup:
+ usb_set_intfdata(iface, NULL);
+ usb_put_dev(i2400mu->usb_dev);
+ free_netdev(net_dev);
+error_alloc_netdev:
+ return result;
+}
+
+
+/*
+ * Disconect a i2400m from the system.
+ *
+ * i2400m_stop() has been called before, so al the rx and tx contexts
+ * have been taken down already. Make sure the queue is stopped,
+ * unregister netdev and i2400m, free and kill.
+ */
+static
+void i2400mu_disconnect(struct usb_interface *iface)
+{
+ struct i2400mu *i2400mu = usb_get_intfdata(iface);
+ struct i2400m *i2400m = &i2400mu->i2400m;
+ struct net_device *net_dev = i2400m->wimax_dev.net_dev;
+ struct device *dev = &iface->dev;
+
+ d_fnstart(3, dev, "(iface %p i2400m %p)\n", iface, i2400m);
+
+ debugfs_remove_recursive(i2400mu->debugfs_dentry);
+ i2400m_release(i2400m);
+ usb_set_intfdata(iface, NULL);
+ usb_put_dev(i2400mu->usb_dev);
+ free_netdev(net_dev);
+ d_fnend(3, dev, "(iface %p i2400m %p) = void\n", iface, i2400m);
+}
+
+
+/*
+ * Get the device ready for USB port or system standby and hibernation
+ *
+ * USB port and system standby are handled the same.
+ *
+ * When the system hibernates, the USB device is powered down and then
+ * up, so we don't really have to do much here, as it will be seen as
+ * a reconnect. Still for simplicity we consider this case the same as
+ * suspend, so that the device has a chance to do notify the base
+ * station (if connected).
+ *
+ * So at the end, the three cases require common handling.
+ *
+ * If at the time of this call the device's firmware is not loaded,
+ * nothing has to be done.
+ *
+ * If the firmware is loaded, we need to:
+ *
+ * - tell the device to go into host interface power save mode, wait
+ * for it to ack
+ *
+ * This is quite more interesting than it is; we need to execute a
+ * command, but this time, we don't want the code in usb-{tx,rx}.c
+ * to call the usb_autopm_get/put_interface() barriers as it'd
+ * deadlock, so we need to decrement i2400mu->do_autopm, that acts
+ * as a poor man's semaphore. Ugly, but it works.
+ *
+ * As well, the device might refuse going to sleep for whichever
+ * reason. In this case we just fail. For system suspend/hibernate,
+ * we *can't* fail. We look at usb_dev->auto_pm to see if the
+ * suspend call comes from the USB stack or from the system and act
+ * in consequence.
+ *
+ * - stop the notification endpoint polling
+ */
+static
+int i2400mu_suspend(struct usb_interface *iface, pm_message_t pm_msg)
+{
+ int result = 0;
+ struct device *dev = &iface->dev;
+ struct i2400mu *i2400mu = usb_get_intfdata(iface);
+ struct usb_device *usb_dev = i2400mu->usb_dev;
+ struct i2400m *i2400m = &i2400mu->i2400m;
+
+ d_fnstart(3, dev, "(iface %p pm_msg %u)\n", iface, pm_msg.event);
+ if (i2400m->updown == 0)
+ goto no_firmware;
+ d_printf(1, dev, "fw up, requesting standby\n");
+ atomic_dec(&i2400mu->do_autopm);
+ result = i2400m_cmd_enter_powersave(i2400m);
+ atomic_inc(&i2400mu->do_autopm);
+ if (result < 0 && usb_dev->auto_pm == 0) {
+ /* System suspend, can't fail */
+ dev_err(dev, "failed to suspend, will reset on resume\n");
+ result = 0;
+ }
+ if (result < 0)
+ goto error_enter_powersave;
+ i2400mu_notification_release(i2400mu);
+ d_printf(1, dev, "fw up, got standby\n");
+error_enter_powersave:
+no_firmware:
+ d_fnend(3, dev, "(iface %p pm_msg %u) = %d\n",
+ iface, pm_msg.event, result);
+ return result;
+}
+
+
+static
+int i2400mu_resume(struct usb_interface *iface)
+{
+ int ret = 0;
+ struct device *dev = &iface->dev;
+ struct i2400mu *i2400mu = usb_get_intfdata(iface);
+ struct i2400m *i2400m = &i2400mu->i2400m;
+
+ d_fnstart(3, dev, "(iface %p)\n", iface);
+ if (i2400m->updown == 0) {
+ d_printf(1, dev, "fw was down, no resume neeed\n");
+ goto out;
+ }
+ d_printf(1, dev, "fw was up, resuming\n");
+ i2400mu_notification_setup(i2400mu);
+ /* USB has flow control, so we don't need to give it time to
+ * come back; otherwise, we'd use something like a get-state
+ * command... */
+out:
+ d_fnend(3, dev, "(iface %p) = %d\n", iface, ret);
+ return ret;
+}
+
+
+static
+struct usb_device_id i2400mu_id_table[] = {
+ { USB_DEVICE(0x8086, 0x0181) },
+ { USB_DEVICE(0x8086, 0x1403) },
+ { USB_DEVICE(0x8086, 0x1405) },
+ { USB_DEVICE(0x8086, 0x0180) },
+ { USB_DEVICE(0x8086, 0x0182) },
+ { USB_DEVICE(0x8086, 0x1406) },
+ { USB_DEVICE(0x8086, 0x1403) },
+ { },
+};
+MODULE_DEVICE_TABLE(usb, i2400mu_id_table);
+
+
+static
+struct usb_driver i2400mu_driver = {
+ .name = KBUILD_MODNAME,
+ .suspend = i2400mu_suspend,
+ .resume = i2400mu_resume,
+ .probe = i2400mu_probe,
+ .disconnect = i2400mu_disconnect,
+ .id_table = i2400mu_id_table,
+ .supports_autosuspend = 1,
+};
+
+static
+int __init i2400mu_driver_init(void)
+{
+ return usb_register(&i2400mu_driver);
+}
+module_init(i2400mu_driver_init);
+
+
+static
+void __exit i2400mu_driver_exit(void)
+{
+ flush_scheduled_work(); /* for the stuff we schedule from sysfs.c */
+ usb_deregister(&i2400mu_driver);
+}
+module_exit(i2400mu_driver_exit);
+
+MODULE_AUTHOR("Intel Corporation <linux-wimax@...el.com>");
+MODULE_DESCRIPTION("Intel 2400M WiMAX networking for USB");
+MODULE_LICENSE("GPL");
+MODULE_FIRMWARE(I2400MU_FW_FILE_NAME);
--
1.5.6.5
--
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