The module was initializing completions whenever it was going to wait on
them, and not when the completion was allocated. This is incorrect
according to the completion docs:
Calling init_completion() on the same completion object twice is
most likely a bug [...]
Re-initialization is also unnecessary because the module never uses
complete_all(). Fix this by only ever initializing the completion a
single time, and log if the completions are not consumed as intended
(this is not a fatal problem, but should not go unnoticed).
Signed-off-by: George Hilliard <thirtythreeforty@xxxxxxxxx>
---
v2: Rebased v1
v3: Removed BUG_ON() calls, and politely log; this failure won't kill us
drivers/staging/mt7621-mmc/sd.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/staging/mt7621-mmc/sd.c b/drivers/staging/mt7621-mmc/sd.c
index ff01872ab972..139533606863 100644
--- a/drivers/staging/mt7621-mmc/sd.c
+++ b/drivers/staging/mt7621-mmc/sd.c
@@ -466,7 +466,10 @@ static unsigned int msdc_command_start(struct msdc_host *host,
host->cmd = cmd;
host->cmd_rsp = resp;
- init_completion(&host->cmd_done);
+ // The completion should have been consumed by the previous command
+ // response handler, because the mmc requests should be serialized
+ if(completion_done(&host->cmd_done))
+ dev_err(mmc_dev(host->mmc), "previous command was not handled\n");
sdr_set_bits(host->base + MSDC_INTEN, wints);
sdc_send_cmd(rawcmd, cmd->arg);
@@ -488,7 +491,6 @@ static unsigned int msdc_command_resp(struct msdc_host *host,
MSDC_INT_ACMD19_DONE;
BUG_ON(in_interrupt());
- //init_completion(&host->cmd_done);
//sdr_set_bits(host->base + MSDC_INTEN, wints);
spin_unlock(&host->lock);
@@ -672,7 +674,11 @@ static int msdc_do_request(struct mmc_host *mmc, struct mmc_request *mrq)
//msdc_clr_fifo(host); /* no need */
msdc_dma_on(); /* enable DMA mode first!! */
- init_completion(&host->xfer_done);
+
+ // The completion should have been consumed by the previous xfer
+ // response handler, because the mmc requests should be serialized
+ if(completion_done(&host->cmd_done))
+ dev_err(mmc_dev(host->mmc), "previous transfer was not handled\n");
/* start the command first*/
if (msdc_command_start(host, cmd, CMD_TIMEOUT) != 0)
@@ -691,7 +697,6 @@ static int msdc_do_request(struct mmc_host *mmc, struct mmc_request *mrq)
/* for read, the data coming too fast, then CRC error
* start DMA no business with CRC.
*/
- //init_completion(&host->xfer_done);
msdc_dma_start(host);
spin_unlock(&host->lock);
@@ -1682,6 +1687,8 @@ static int msdc_drv_probe(struct platform_device *pdev)
}
msdc_init_gpd_bd(host, &host->dma);
+ init_completion(&host->cmd_done);
+ init_completion(&host->xfer_done);
INIT_DELAYED_WORK(&host->card_delaywork, msdc_tasklet_card);
spin_lock_init(&host->lock);
msdc_init_hw(host);
--
2.21.0
