diff options
| -rw-r--r-- | drivers/dma/stm32/stm32-dma3.c | 75 |
1 files changed, 74 insertions, 1 deletions
diff --git a/drivers/dma/stm32/stm32-dma3.c b/drivers/dma/stm32/stm32-dma3.c index a1583face7ec..29ea510fa539 100644 --- a/drivers/dma/stm32/stm32-dma3.c +++ b/drivers/dma/stm32/stm32-dma3.c @@ -1237,6 +1237,10 @@ static struct dma_async_tx_descriptor *stm32_dma3_prep_dma_memcpy(struct dma_cha bool prevent_refactor = !!FIELD_GET(STM32_DMA3_DT_NOPACK, chan->dt_config.tr_conf) || !!FIELD_GET(STM32_DMA3_DT_NOREFACT, chan->dt_config.tr_conf); + /* Semaphore could be lost during suspend/resume */ + if (chan->semaphore_mode && !chan->semaphore_taken) + return NULL; + count = stm32_dma3_get_ll_count(chan, len, prevent_refactor); swdesc = stm32_dma3_chan_desc_alloc(chan, count); @@ -1297,6 +1301,10 @@ static struct dma_async_tx_descriptor *stm32_dma3_prep_slave_sg(struct dma_chan !!FIELD_GET(STM32_DMA3_DT_NOREFACT, chan->dt_config.tr_conf); int ret; + /* Semaphore could be lost during suspend/resume */ + if (chan->semaphore_mode && !chan->semaphore_taken) + return NULL; + count = 0; for_each_sg(sgl, sg, sg_len, i) count += stm32_dma3_get_ll_count(chan, sg_dma_len(sg), prevent_refactor); @@ -1383,6 +1391,10 @@ static struct dma_async_tx_descriptor *stm32_dma3_prep_dma_cyclic(struct dma_cha u32 count, i, ctr1, ctr2; int ret; + /* Semaphore could be lost during suspend/resume */ + if (chan->semaphore_mode && !chan->semaphore_taken) + return NULL; + if (!buf_len || !period_len || period_len > STM32_DMA3_MAX_BLOCK_SIZE) { dev_err(chan2dev(chan), "Invalid buffer/period length\n"); return NULL; @@ -1932,8 +1944,69 @@ static int stm32_dma3_runtime_resume(struct device *dev) return ret; } +static int stm32_dma3_pm_suspend(struct device *dev) +{ + struct stm32_dma3_ddata *ddata = dev_get_drvdata(dev); + struct dma_device *dma_dev = &ddata->dma_dev; + struct dma_chan *c; + int ccr, ret; + + ret = pm_runtime_resume_and_get(dev); + if (ret < 0) + return ret; + + list_for_each_entry(c, &dma_dev->channels, device_node) { + struct stm32_dma3_chan *chan = to_stm32_dma3_chan(c); + + ccr = readl_relaxed(ddata->base + STM32_DMA3_CCR(chan->id)); + if (ccr & CCR_EN) { + dev_warn(dev, "Suspend is prevented: %s still in use by %s\n", + dma_chan_name(c), dev_name(c->slave)); + pm_runtime_put_sync(dev); + return -EBUSY; + } + } + + pm_runtime_put_sync(dev); + + pm_runtime_force_suspend(dev); + + return 0; +} + +static int stm32_dma3_pm_resume(struct device *dev) +{ + struct stm32_dma3_ddata *ddata = dev_get_drvdata(dev); + struct dma_device *dma_dev = &ddata->dma_dev; + struct dma_chan *c; + int ret; + + ret = pm_runtime_force_resume(dev); + if (ret < 0) + return ret; + + ret = pm_runtime_resume_and_get(dev); + if (ret < 0) + return ret; + + /* + * Channel semaphores need to be restored in case of registers reset during low power. + * stm32_dma3_get_chan_sem() will prior check the semaphore status. + */ + list_for_each_entry(c, &dma_dev->channels, device_node) { + struct stm32_dma3_chan *chan = to_stm32_dma3_chan(c); + + if (chan->semaphore_mode && chan->semaphore_taken) + stm32_dma3_get_chan_sem(chan); + } + + pm_runtime_put_sync(dev); + + return 0; +} + static const struct dev_pm_ops stm32_dma3_pm_ops = { - SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume) + SYSTEM_SLEEP_PM_OPS(stm32_dma3_pm_suspend, stm32_dma3_pm_resume) RUNTIME_PM_OPS(stm32_dma3_runtime_suspend, stm32_dma3_runtime_resume, NULL) }; |