We may use special helper macro to poll IO till condition or timeout occurs. Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> --- v2: wrapped long line (Bingbu) drivers/media/pci/intel/ipu3/ipu3-cio2.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/drivers/media/pci/intel/ipu3/ipu3-cio2.c b/drivers/media/pci/intel/ipu3/ipu3-cio2.c index 36b4c7730f43..7bcde3ba8f6e 100644 --- a/drivers/media/pci/intel/ipu3/ipu3-cio2.c +++ b/drivers/media/pci/intel/ipu3/ipu3-cio2.c @@ -14,6 +14,7 @@ #include <linux/delay.h> #include <linux/interrupt.h> +#include <linux/iopoll.h> #include <linux/module.h> #include <linux/pci.h> #include <linux/pfn.h> @@ -507,8 +508,10 @@ static int cio2_hw_init(struct cio2_device *cio2, struct cio2_queue *q) static void cio2_hw_exit(struct cio2_device *cio2, struct cio2_queue *q) { - void __iomem *base = cio2->base; - unsigned int i, maxloops = 1000; + void __iomem *const base = cio2->base; + unsigned int i; + u32 value; + int ret; /* Disable CSI receiver and MIPI backend devices */ writel(0, q->csi_rx_base + CIO2_REG_IRQCTRL_MASK); @@ -518,13 +521,10 @@ static void cio2_hw_exit(struct cio2_device *cio2, struct cio2_queue *q) /* Halt DMA */ writel(0, base + CIO2_REG_CDMAC0(CIO2_DMA_CHAN)); - do { - if (readl(base + CIO2_REG_CDMAC0(CIO2_DMA_CHAN)) & - CIO2_CDMAC0_DMA_HALTED) - break; - usleep_range(1000, 2000); - } while (--maxloops); - if (!maxloops) + ret = readl_poll_timeout(base + CIO2_REG_CDMAC0(CIO2_DMA_CHAN), + value, value & CIO2_CDMAC0_DMA_HALTED, + 4000, 2000000); + if (ret) dev_err(&cio2->pci_dev->dev, "DMA %i can not be halted\n", CIO2_DMA_CHAN); -- 2.28.0