From 9df3bd5520038225ceb3927021e6ea811c000c5b Mon Sep 17 00:00:00 2001 From: Pierre Yves MORDRET Date: Tue, 13 Mar 2018 17:42:05 +0100 Subject: [PATCH] dmaengine: stm32-dma: properly mask irq bits A single register of the controller holds the information for four dma channels. The functions stm32_dma_irq_status() don't mask the relevant bits after the shift, thus adjacent channel's status is also reported in the returned value. Fixed by masking the value before returning it. Similarly, the function stm32_dma_irq_clear() don't mask the input value before shifting it, thus an incorrect input value could disable the interrupts of adjacent channels. Fixed by masking the input value before using it. Signed-off-by: Pierre-Yves MORDRET Signed-off-by: Antonio Borneo Signed-off-by: Vinod Koul --- drivers/dma/stm32-dma.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/dma/stm32-dma.c b/drivers/dma/stm32-dma.c index 05a2974..8c58073 100644 --- a/drivers/dma/stm32-dma.c +++ b/drivers/dma/stm32-dma.c @@ -38,6 +38,10 @@ #define STM32_DMA_TEI BIT(3) /* Transfer Error Interrupt */ #define STM32_DMA_DMEI BIT(2) /* Direct Mode Error Interrupt */ #define STM32_DMA_FEI BIT(0) /* FIFO Error Interrupt */ +#define STM32_DMA_MASKI (STM32_DMA_TCI \ + | STM32_DMA_TEI \ + | STM32_DMA_DMEI \ + | STM32_DMA_FEI) /* DMA Stream x Configuration Register */ #define STM32_DMA_SCR(x) (0x0010 + 0x18 * (x)) /* x = 0..7 */ @@ -405,7 +409,7 @@ static u32 stm32_dma_irq_status(struct stm32_dma_chan *chan) flags = dma_isr >> (((chan->id & 2) << 3) | ((chan->id & 1) * 6)); - return flags; + return flags & STM32_DMA_MASKI; } static void stm32_dma_irq_clear(struct stm32_dma_chan *chan, u32 flags) @@ -420,6 +424,7 @@ static void stm32_dma_irq_clear(struct stm32_dma_chan *chan, u32 flags) * If (ch % 4) is 2 or 3, left shift the mask by 16 bits. * If (ch % 4) is 1 or 3, additionally left shift the mask by 6 bits. */ + flags &= STM32_DMA_MASKI; dma_ifcr = flags << (((chan->id & 2) << 3) | ((chan->id & 1) * 6)); if (chan->id & 4) -- 2.7.4