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mwifiex: sdio: reset adapter using mmc_hw_reset

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Since 1fb654fd97ff("mmc: sdio: add reset callback to bus operations"),
sdio cards can be power cycled using mmc_hw_reset.
The use mmc_remove_host/mmc_add_host is discouraged, because these are
internal functions to the mmc core and should only be used by mmc hosts

Signed-off-by: Andreas Fenkart <afenkart@gmail.com>
Acked-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
This commit is contained in:
Andreas Fenkart 2015-07-16 18:50:01 +02:00 committed by Kalle Valo
parent 9dc20a6496
commit b4336a282d
2 changed files with 38 additions and 14 deletions
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49
drivers/net/wireless/mwifiex/sdio.c
View File

@ -91,6 +91,7 @@ mwifiex_sdio_probe(struct sdio_func *func, const struct sdio_device_id *id)
return -ENOMEM;
card->func = func;
card->device_id = id;
func->card->quirks |= MMC_QUIRK_BLKSZ_FOR_BYTE_MODE;
@ -2107,26 +2108,46 @@ mwifiex_update_mp_end_port(struct mwifiex_adapter *adapter, u16 port)
port, card->mp_data_port_mask);
}
static void mwifiex_recreate_adapter(struct sdio_mmc_card *card)
{
struct sdio_func *func = card->func;
const struct sdio_device_id *device_id = card->device_id;
/* TODO mmc_hw_reset does not require destroying and re-probing the
* whole adapter. Hence there was no need to for this rube-goldberg
* design to reload the fw from an external workqueue. If we don't
* destroy the adapter we could reload the fw from
* mwifiex_main_work_queue directly.
* The real difficulty with fw reset is to restore all the user
* settings applied through ioctl. By destroying and recreating the
* adapter, we take the easy way out, since we rely on user space to
* restore them. We assume that user space will treat the new
* incarnation of the adapter(interfaces) as if they had been just
* discovered and initializes them from scratch.
*/
mwifiex_sdio_remove(func);
/* power cycle the adapter */
sdio_claim_host(func);
mmc_hw_reset(func->card->host);
sdio_release_host(func);
mwifiex_sdio_probe(func, device_id);
}
static struct mwifiex_adapter *save_adapter;
static void mwifiex_sdio_card_reset_work(struct mwifiex_adapter *adapter)
{
struct sdio_mmc_card *card = adapter->card;
struct mmc_host *target = card->func->card->host;
/* The actual reset operation must be run outside of driver thread.
* This is because mmc_remove_host() will cause the device to be
* instantly destroyed, and the driver then needs to end its thread,
* leading to a deadlock.
*
* We run it in a totally independent workqueue.
/* TODO card pointer is unprotected. If the adapter is removed
* physically, sdio core might trigger mwifiex_sdio_remove, before this
* workqueue is run, which will destroy the adapter struct. When this
* workqueue eventually exceutes it will dereference an invalid adapter
* pointer
*/
mwifiex_dbg(adapter, WARN, "Resetting card...\n");
mmc_remove_host(target);
/* 200ms delay is based on experiment with sdhci controller */
mdelay(200);
target->rescan_entered = 0; /* rescan non-removable cards */
mmc_add_host(target);
mwifiex_recreate_adapter(card);
}
/* This function read/write firmware */

3
drivers/net/wireless/mwifiex/sdio.h
View File

@ -262,6 +262,9 @@ struct sdio_mmc_card {
struct mwifiex_sdio_mpa_tx mpa_tx;
struct mwifiex_sdio_mpa_rx mpa_rx;
/* needed for card reset */
const struct sdio_device_id *device_id;
};
struct mwifiex_sdio_device {