mmc: tmio: fix a deadlock

Currently the tmio-mmc driver contains a recursive runtime PM method
invocation, which leads to a deadlock on a mutex. Avoid it by taking
care not to request DMA too early.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
This commit is contained in:
Guennadi Liakhovetski 2011-07-14 18:39:10 +02:00 committed by Chris Ball
parent 332bdb506f
commit 162f43e31c
3 changed files with 11 additions and 3 deletions

View File

@ -109,6 +109,7 @@ static inline void tmio_mmc_kunmap_atomic(struct scatterlist *sg,
#if defined(CONFIG_MMC_SDHI) || defined(CONFIG_MMC_SDHI_MODULE)
void tmio_mmc_start_dma(struct tmio_mmc_host *host, struct mmc_data *data);
void tmio_mmc_enable_dma(struct tmio_mmc_host *host, bool enable);
void tmio_mmc_request_dma(struct tmio_mmc_host *host, struct tmio_mmc_data *pdata);
void tmio_mmc_release_dma(struct tmio_mmc_host *host);
#else
@ -117,6 +118,10 @@ static inline void tmio_mmc_start_dma(struct tmio_mmc_host *host,
{
}
static inline void tmio_mmc_enable_dma(struct tmio_mmc_host *host, bool enable)
{
}
static inline void tmio_mmc_request_dma(struct tmio_mmc_host *host,
struct tmio_mmc_data *pdata)
{

View File

@ -22,8 +22,11 @@
#define TMIO_MMC_MIN_DMA_LEN 8
static void tmio_mmc_enable_dma(struct tmio_mmc_host *host, bool enable)
void tmio_mmc_enable_dma(struct tmio_mmc_host *host, bool enable)
{
if (!host->chan_tx || !host->chan_rx)
return;
#if defined(CONFIG_SUPERH) || defined(CONFIG_ARCH_SHMOBILE)
/* Switch DMA mode on or off - SuperH specific? */
sd_ctrl_write16(host, CTL_DMA_ENABLE, enable ? 2 : 0);

View File

@ -984,7 +984,7 @@ int tmio_mmc_host_resume(struct device *dev)
if (host->pm_global) {
/* Runtime PM resume callback didn't run */
tmio_mmc_reset(host);
tmio_mmc_request_dma(host, host->pdata);
tmio_mmc_enable_dma(host, true);
host->pm_global = false;
}
@ -1007,7 +1007,7 @@ int tmio_mmc_host_runtime_resume(struct device *dev)
struct tmio_mmc_data *pdata = host->pdata;
tmio_mmc_reset(host);
tmio_mmc_request_dma(host, host->pdata);
tmio_mmc_enable_dma(host, true);
if (pdata->power) {
/* Only entered after a card-insert interrupt */