From 45b281e457dc5e80650ca6808fb08df49b677f03 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Mon, 10 Feb 2014 11:49:37 -0700 Subject: [PATCH] staging: comedi: s626: use comedi_timeout() Use comedi_timeout() to wait for the analog input end-of-conversion. This prevents a deadlock condition that could occur by providing a timeout in case the end-of-conversion does not happen. Signed-off-by: H Hartley Sweeten Cc: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/s626.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) diff --git a/drivers/staging/comedi/drivers/s626.c b/drivers/staging/comedi/drivers/s626.c index 9e711ee13bb7..5ba4b4ae6507 100644 --- a/drivers/staging/comedi/drivers/s626.c +++ b/drivers/staging/comedi/drivers/s626.c @@ -1846,6 +1846,20 @@ static int s626_ai_rinsn(struct comedi_device *dev, } #endif +static int s626_ai_eoc(struct comedi_device *dev, + struct comedi_subdevice *s, + struct comedi_insn *insn, + unsigned long context) +{ + struct s626_private *devpriv = dev->private; + unsigned int status; + + status = readl(devpriv->mmio + S626_P_PSR); + if (status & S626_PSR_GPIO2) + return 0; + return -EBUSY; +} + static int s626_ai_insn_read(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_insn *insn, unsigned int *data) @@ -1856,6 +1870,7 @@ static int s626_ai_insn_read(struct comedi_device *dev, uint16_t adc_spec = 0; uint32_t gpio_image; uint32_t tmp; + int ret; int n; /* @@ -1897,8 +1912,9 @@ static int s626_ai_insn_read(struct comedi_device *dev, */ /* Wait for ADC done */ - while (!(readl(devpriv->mmio + S626_P_PSR) & S626_PSR_GPIO2)) - ; + ret = comedi_timeout(dev, s, insn, s626_ai_eoc, 0); + if (ret) + return ret; /* Fetch ADC data */ if (n != 0) { -- 2.30.2