i2400m/SDIO: probe/disconnect, dev init/shutdown and reset backends

/*

 * Intel Wireless WiMAX Connection 2400m

 * Linux driver model glue for the SDIO device, reset & fw upload

 *

 *

 * Copyright (C) 2007-2008 Intel Corporation <linux-wimax@intel.com>

 * Dirk Brandewie <dirk.j.brandewie@intel.com>

 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>

 * Yanir Lubetkin <yanirx.lubetkin@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.

 *

 *

 * See i2400m-sdio.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

 *

 * i2400m_probe()

 *   alloc_netdev()

 *     i2400ms_netdev_setup()

 *       i2400ms_init()

 *       i2400m_netdev_setup()

 *   i2400ms_enable_function()

 *   i2400m_setup()

 *

 * i2400m_remove()

 *     i2400m_release()

 *     free_netdev(net_dev)

 *

 * i2400ms_bus_reset()            Called by i2400m->bus_reset

 *   __i2400ms_reset()

 *     __i2400ms_send_barker()

 *

 * i2400ms_bus_dev_start()        Called by i2400m_dev_start() [who is

 *   i2400ms_tx_setup()           called by i2400m_setup()]

 *   i2400ms_rx_setup()

 *

 * i2400ms_bus_dev_stop()         Called by i2400m_dev_stop() [who is

 *   i2400ms_rx_release()         is called by i2400m_release()]

 *   i2400ms_tx_release()

 *

 */

#include <linux/debugfs.h>

#include <linux/mmc/sdio.h>

#include <linux/mmc/sdio_func.h>

#include "i2400m-sdio.h"

#include <linux/wimax/i2400m.h>

#define D_SUBMODULE main

#include "sdio-debug-levels.h"

/* IOE WiMAX function timeout in seconds */

static int ioe_timeout = 2;

module_param(ioe_timeout, int, 0);

/* Our firmware file name */

#define I2400MS_FW_FILE_NAME "i2400m-fw-sdio-" I2400M_FW_VERSION ".sbcf"

/*

 * Enable the SDIO function

 *

 * Tries to enable the SDIO function; might fail if it is still not

 * ready (in some hardware, the SDIO WiMAX function is only enabled

 * when we ask it to explicitly doing). Tries until a timeout is

 * reached.

 *

 * The reverse of this is...sdio_disable_function()

 *

 * Returns: 0 if the SDIO function was enabled, < 0 errno code on

 *     error (-ENODEV when it was unable to enable the function).

 */

static

int i2400ms_enable_function(struct sdio_func *func)

{

	u64 timeout;

	int err;

	struct device *dev = &func->dev;

	d_fnstart(3, dev, "(func %p)\n", func);

	/* Setup timeout (FIXME: This needs to read the CIS table to

	 * get a real timeout) and then wait for the device to signal

	 * it is ready */

	timeout = get_jiffies_64() + ioe_timeout * HZ;

	err = -ENODEV;

	while (err != 0 && time_before64(get_jiffies_64(), timeout)) {

		sdio_claim_host(func);

		err = sdio_enable_func(func);

		if (0 == err) {

			sdio_release_host(func);

			d_printf(2, dev, "SDIO function enabled\n");

			goto function_enabled;

		}

		d_printf(2, dev, "SDIO function failed to enable: %d\n", err);

		sdio_disable_func(func);

		sdio_release_host(func);

		msleep(I2400MS_INIT_SLEEP_INTERVAL);

	}

	/* If timed out, device is not there yet -- get -ENODEV so

	 * the device driver core will retry later on. */

	if (err == -ETIME) {

		dev_err(dev, "Can't enable WiMAX function; "

			" has the function been enabled?\n");

		err = -ENODEV;

	}

function_enabled:

	d_fnend(3, dev, "(func %p) = %d\n", func, err);

	return err;

}

/*

 * Setup driver resources needed to communicate with the device

 *

 * The fw needs some time to settle, and it was just uploaded,

 * so give it a break first. I'd prefer to just wait for the device to

 * send something, but seems the poking we do to enable SDIO stuff

 * interferes with it, so just give it a break before starting...

 */

static

int i2400ms_bus_dev_start(struct i2400m *i2400m)

{

	int result;

	struct i2400ms *i2400ms = container_of(i2400m, struct i2400ms, i2400m);

	struct sdio_func *func = i2400ms->func;

	struct device *dev = &func->dev;

	d_fnstart(3, dev, "(i2400m %p)\n", i2400m);

	msleep(200);

	result = i2400ms_rx_setup(i2400ms);

	if (result < 0)

		goto error_rx_setup;

	result = i2400ms_tx_setup(i2400ms);

	if (result < 0)

		goto error_tx_setup;

	d_fnend(3, dev, "(i2400m %p) = %d\n", i2400m, result);

	return result;

	i2400ms_tx_release(i2400ms);

error_tx_setup:

	i2400ms_rx_release(i2400ms);

error_rx_setup:

	d_fnend(3, dev, "(i2400m %p) = void\n", i2400m);

	return result;

}

static

void i2400ms_bus_dev_stop(struct i2400m *i2400m)

{

	struct i2400ms *i2400ms = container_of(i2400m, struct i2400ms, i2400m);

	struct sdio_func *func = i2400ms->func;

	struct device *dev = &func->dev;

	d_fnstart(3, dev, "(i2400m %p)\n", i2400m);

	i2400ms_rx_release(i2400ms);

	i2400ms_tx_release(i2400ms);

	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 the SDIO host controller

 * expects alignment (unknown exactly which) which the stack won't

 * really provide and certain arches/host-controller combinations

 * cannot use stack/vmalloc/text areas for DMA transfers.

 */

static

int __i2400ms_send_barker(struct i2400ms *i2400ms,

			  const __le32 *barker, size_t barker_size)

{

	int  ret;

	struct sdio_func *func = i2400ms->func;

	struct device *dev = &func->dev;

	void *buffer;

	ret = -ENOMEM;

	buffer = kmalloc(I2400MS_BLK_SIZE, GFP_KERNEL);

	if (buffer == NULL)

		goto error_kzalloc;

	memcpy(buffer, barker, barker_size);

	sdio_claim_host(func);

	ret = sdio_memcpy_toio(func, 0, buffer, I2400MS_BLK_SIZE);

	sdio_release_host(func);

	if (ret < 0)

		d_printf(0, dev, "E: barker error: %d\n", ret);

	kfree(buffer);

error_kzalloc:

	return ret;

}

/*

 * Reset a device at different levels (warm, cold or bus)

 *

 * @i2400ms: device descriptor

 * @reset_type: soft, warm or bus reset (I2400M_RT_WARM/SOFT/BUS)

 *

 * FIXME: not tested -- need to confirm expected effects

 *

 * Warm and cold resets get an SDIO reset if they fail (unimplemented)

 *

 * 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 i2400ms_bus_reset(struct i2400m *i2400m, enum i2400m_reset_type rt)

{

	int result;

	struct i2400ms *i2400ms =

		container_of(i2400m, struct i2400ms, 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),

	};

	if (rt == I2400M_RT_WARM)

		result = __i2400ms_send_barker(i2400ms, i2400m_WARM_BOOT_BARKER,

					       sizeof(i2400m_WARM_BOOT_BARKER));

	else if (rt == I2400M_RT_COLD)

		result = __i2400ms_send_barker(i2400ms, i2400m_COLD_BOOT_BARKER,

					       sizeof(i2400m_COLD_BOOT_BARKER));

	else if (rt == I2400M_RT_BUS) {

do_bus_reset:

		dev_err(dev, "FIXME: SDIO bus reset not implemented\n");

		result = rt == I2400M_RT_WARM ? -ENODEV : -ENOSYS;

	} else

		BUG();

	if (result < 0 && rt != I2400M_RT_BUS) {

		dev_err(dev, "%s reset failed (%d); trying SDIO reset\n",

			rt == I2400M_RT_WARM ? "warm" : "cold", result);

		rt = I2400M_RT_BUS;

		goto do_bus_reset;

	}

	return result;

}

static

void i2400ms_netdev_setup(struct net_device *net_dev)

{

	struct i2400m *i2400m = net_dev_to_i2400m(net_dev);

	struct i2400ms *i2400ms = container_of(i2400m, struct i2400ms, i2400m);

	i2400ms_init(i2400ms);

	i2400m_netdev_setup(net_dev);

}

/*

 * Debug levels control; see debug.h

 */

struct d_level D_LEVEL[] = {

	D_SUBMODULE_DEFINE(main),

	D_SUBMODULE_DEFINE(tx),

	D_SUBMODULE_DEFINE(rx),

	D_SUBMODULE_DEFINE(fw),

};

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 i2400ms_debugfs_add(struct i2400ms *i2400ms)

{

	int result;

	struct dentry *dentry = i2400ms->i2400m.wimax_dev.debugfs_dentry;

	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;

	}

	i2400ms->debugfs_dentry = dentry;

	__debugfs_register("dl_", main, dentry);

	__debugfs_register("dl_", tx, dentry);

	__debugfs_register("dl_", rx, dentry);

	__debugfs_register("dl_", fw, dentry);

	return 0;

error:

	debugfs_remove_recursive(i2400ms->debugfs_dentry);

	return result;

}

/*

 * Probe a i2400m interface and register it

 *

 * @func:    SDIO function

 * @id:      SDIO device 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.

 *

 * Initialization is tricky; some instances of the hw are packed with

 * others in a way that requires a third driver that enables the WiMAX

 * function. In those cases, we can't enable the SDIO function and

 * we'll return with -ENODEV. When the driver that enables the WiMAX

 * function does its thing, it has to do a bus_rescan_devices() on the

 * SDIO bus so this driver is called again to enumerate the WiMAX

 * function.

 */

static

int i2400ms_probe(struct sdio_func *func,

		  const struct sdio_device_id *id)

{

	int result;

	struct net_device *net_dev;

	struct device *dev = &func->dev;

	struct i2400m *i2400m;

	struct i2400ms *i2400ms;

	/* Allocate instance [calls i2400m_netdev_setup() on it]. */

	result = -ENOMEM;

	net_dev = alloc_netdev(sizeof(*i2400ms), "wmx%d",

			       i2400ms_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);

	i2400ms = container_of(i2400m, struct i2400ms, i2400m);

	i2400m->wimax_dev.net_dev = net_dev;

	i2400ms->func = func;

	sdio_set_drvdata(func, i2400ms);

	i2400m->bus_tx_block_size = I2400MS_BLK_SIZE;

	i2400m->bus_pl_size_max = I2400MS_PL_SIZE_MAX;

	i2400m->bus_dev_start = i2400ms_bus_dev_start;

	i2400m->bus_dev_stop = i2400ms_bus_dev_stop;

	i2400m->bus_tx_kick = i2400ms_bus_tx_kick;

	i2400m->bus_reset = i2400ms_bus_reset;

	i2400m->bus_bm_cmd_send = i2400ms_bus_bm_cmd_send;

	i2400m->bus_bm_wait_for_ack = i2400ms_bus_bm_wait_for_ack;

	i2400m->bus_fw_name = I2400MS_FW_FILE_NAME;

	i2400m->bus_bm_mac_addr_impaired = 1;

	result = i2400ms_enable_function(i2400ms->func);

	if (result < 0) {

		dev_err(dev, "Cannot enable SDIO function: %d\n", result);

		goto error_func_enable;

	}

	sdio_claim_host(func);

	result = sdio_set_block_size(func, I2400MS_BLK_SIZE);

	if (result < 0) {

		dev_err(dev, "Failed to set block size: %d\n", result);

		goto error_set_blk_size;

	}

	sdio_release_host(func);

	result = i2400m_setup(i2400m, I2400M_BRI_NO_REBOOT);

	if (result < 0) {

		dev_err(dev, "cannot setup device: %d\n", result);

		goto error_setup;

	}

	result = i2400ms_debugfs_add(i2400ms);

	if (result < 0) {

		dev_err(dev, "cannot create SDIO debugfs: %d\n",

			result);

		goto error_debugfs_add;

	}

	return 0;

error_debugfs_add:

	i2400m_release(i2400m);

error_setup:

	sdio_set_drvdata(func, NULL);

	sdio_claim_host(func);

error_set_blk_size:

	sdio_disable_func(func);

	sdio_release_host(func);

error_func_enable:

	free_netdev(net_dev);

error_alloc_netdev:

	return result;

}

static

void i2400ms_remove(struct sdio_func *func)

{

	struct device *dev = &func->dev;

	struct i2400ms *i2400ms = sdio_get_drvdata(func);

	struct i2400m *i2400m = &i2400ms->i2400m;

	struct net_device *net_dev = i2400m->wimax_dev.net_dev;

	d_fnstart(3, dev, "SDIO func %p\n", func);

	debugfs_remove_recursive(i2400ms->debugfs_dentry);

	i2400m_release(i2400m);

	sdio_set_drvdata(func, NULL);

	sdio_claim_host(func);

	sdio_disable_func(func);

	sdio_release_host(func);

	free_netdev(net_dev);

	d_fnend(3, dev, "SDIO func %p\n", func);

}

enum {

	I2400MS_INTEL_VID = 0x89,

};

static

const struct sdio_device_id i2400ms_sdio_ids[] = {

	/* Intel: i2400m WiMAX over SDIO */

	{ SDIO_DEVICE(I2400MS_INTEL_VID, 0x1402) },

	{ }, 			/* end: all zeroes */

};

MODULE_DEVICE_TABLE(sdio, i2400ms_sdio_ids);

static

struct sdio_driver i2400m_sdio_driver = {

	.name		= KBUILD_MODNAME,

	.probe		= i2400ms_probe,

	.remove		= i2400ms_remove,

	.id_table	= i2400ms_sdio_ids,

};

static

int __init i2400ms_driver_init(void)

{

	return sdio_register_driver(&i2400m_sdio_driver);

}

module_init(i2400ms_driver_init);

static

void __exit i2400ms_driver_exit(void)

{

	flush_scheduled_work();	/* for the stuff we schedule */

	sdio_unregister_driver(&i2400m_sdio_driver);

}

module_exit(i2400ms_driver_exit);

MODULE_AUTHOR("Intel Corporation <linux-wimax@intel.com>");

MODULE_DESCRIPTION("Intel 2400M WiMAX networking for SDIO");

MODULE_LICENSE("GPL");

MODULE_FIRMWARE(I2400MS_FW_FILE_NAME);