From 8b2979febc134f038f3c8396cb04893f96e03b4f Mon Sep 17 00:00:00 2001 From: Even Xu Date: Fri, 21 Oct 2016 15:48:39 -0700 Subject: [PATCH] HID: intel-ish-hid: Move DMA disable code to new function Add a new function ish_disable_dma() and move DMA disable operations here, so that this functionality can be reused. Signed-off-by: Even Xu Acked-by: Srinivas Pandruvada Signed-off-by: Jiri Kosina --- drivers/hid/intel-ish-hid/ipc/ipc.c | 42 ++++++++++++++++++++++------- 1 file changed, 32 insertions(+), 10 deletions(-) diff --git a/drivers/hid/intel-ish-hid/ipc/ipc.c b/drivers/hid/intel-ish-hid/ipc/ipc.c index d4c57214ba6c..0e0dfa616fab 100644 --- a/drivers/hid/intel-ish-hid/ipc/ipc.c +++ b/drivers/hid/intel-ish-hid/ipc/ipc.c @@ -637,6 +637,36 @@ eoi: return IRQ_HANDLED; } +/** + * ish_disable_dma() - disable dma communication between host and ISHFW + * @dev: ishtp device pointer + * + * Clear the dma enable bit and wait for dma inactive. + * + * Return: 0 for success else error code. + */ +static int ish_disable_dma(struct ishtp_device *dev) +{ + unsigned int dma_delay; + + /* Clear the dma enable bit */ + ish_reg_write(dev, IPC_REG_ISH_RMP2, 0); + + /* wait for dma inactive */ + for (dma_delay = 0; dma_delay < MAX_DMA_DELAY && + _ish_read_fw_sts_reg(dev) & (IPC_ISH_IN_DMA); + dma_delay += 5) + mdelay(5); + + if (dma_delay >= MAX_DMA_DELAY) { + dev_err(dev->devc, + "Wait for DMA inactive timeout\n"); + return -EBUSY; + } + + return 0; +} + /** * ish_wakeup() - wakeup ishfw from waiting-for-host state * @dev: ishtp device pointer @@ -671,7 +701,6 @@ static int _ish_hw_reset(struct ishtp_device *dev) { struct pci_dev *pdev = dev->pdev; int rv; - unsigned int dma_delay; uint16_t csr; if (!pdev) @@ -686,15 +715,8 @@ static int _ish_hw_reset(struct ishtp_device *dev) return -EINVAL; } - /* Now trigger reset to FW */ - ish_reg_write(dev, IPC_REG_ISH_RMP2, 0); - - for (dma_delay = 0; dma_delay < MAX_DMA_DELAY && - _ish_read_fw_sts_reg(dev) & (IPC_ISH_IN_DMA); - dma_delay += 5) - mdelay(5); - - if (dma_delay >= MAX_DMA_DELAY) { + /* Disable dma communication between FW and host */ + if (ish_disable_dma(dev)) { dev_err(&pdev->dev, "Can't reset - stuck with DMA in-progress\n"); return -EBUSY; -- 2.20.1