| From 3d74cc1d62a8973298e5f559517f1f9cc362cfe4 Mon Sep 17 00:00:00 2001 |
| From: Guennadi Liakhovetski <g.liakhovetski@gmx.de> |
| Date: Thu, 14 Jul 2011 18:39:10 +0200 |
| Subject: 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> |
| (cherry picked from commit 162f43e31c5a376ec16336e5d0ac973373d54c89) |
| |
| Signed-off-by: Simon Horman <horms@verge.net.au> |
| --- |
| drivers/mmc/host/tmio_mmc.h | 5 +++++ |
| drivers/mmc/host/tmio_mmc_dma.c | 5 ++++- |
| drivers/mmc/host/tmio_mmc_pio.c | 4 ++-- |
| 3 files changed, 11 insertions(+), 3 deletions(-) |
| |
| diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h |
| index ba0d8e6..087d880 100644 |
| --- a/drivers/mmc/host/tmio_mmc.h |
| +++ b/drivers/mmc/host/tmio_mmc.h |
| @@ -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) |
| { |
| diff --git a/drivers/mmc/host/tmio_mmc_dma.c b/drivers/mmc/host/tmio_mmc_dma.c |
| index 7e86662..2aa616d 100644 |
| --- a/drivers/mmc/host/tmio_mmc_dma.c |
| +++ b/drivers/mmc/host/tmio_mmc_dma.c |
| @@ -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); |
| diff --git a/drivers/mmc/host/tmio_mmc_pio.c b/drivers/mmc/host/tmio_mmc_pio.c |
| index 221ffb7..1f16357 100644 |
| --- a/drivers/mmc/host/tmio_mmc_pio.c |
| +++ b/drivers/mmc/host/tmio_mmc_pio.c |
| @@ -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 */ |
| -- |
| 1.7.10.2.565.gbd578b5 |
| |