From: Ian Abbott <abbotti@mev.co.uk>
To: devel@driverdev.osuosl.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Ian Abbott <abbotti@mev.co.uk>
Subject: [PATCH 13/14] staging: comedi: ni_65xx: Use 16-bit 0 for interrupt data
Date: Tue, 23 Feb 2021 14:30:54 +0000 [thread overview]
Message-ID: <20210223143055.257402-14-abbotti@mev.co.uk> (raw)
In-Reply-To: <20210223143055.257402-1-abbotti@mev.co.uk>
The ni_65xx driver has an "interrupt" subdevice that supports Comedi
asynchronous commands, placing a value in the Comedi buffer for each
interrupt. The subdevice uses Comedi's 16-bit sample format but the
interrupt handler is calling `comedi_buf_write_samples()` with the
address of a 32-bit integer `&s->state`. On bigendian machines, this
will copy 2 bytes from the wrong end of the 32-bit integer. This isn't
really a problem since `s->state` will always be 0 for this subdevice,
but clean it up by using a 16-bit variable initialized to 0 to pass the
value.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
---
drivers/staging/comedi/drivers/ni_65xx.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/staging/comedi/drivers/ni_65xx.c b/drivers/staging/comedi/drivers/ni_65xx.c
index eb3f9f7109da..7cd8497420f2 100644
--- a/drivers/staging/comedi/drivers/ni_65xx.c
+++ b/drivers/staging/comedi/drivers/ni_65xx.c
@@ -472,6 +472,7 @@ static irqreturn_t ni_65xx_interrupt(int irq, void *d)
struct comedi_device *dev = d;
struct comedi_subdevice *s = dev->read_subdev;
unsigned int status;
+ unsigned short val = 0;
status = readb(dev->mmio + NI_65XX_STATUS_REG);
if ((status & NI_65XX_STATUS_INT) == 0)
@@ -482,7 +483,7 @@ static irqreturn_t ni_65xx_interrupt(int irq, void *d)
writeb(NI_65XX_CLR_EDGE_INT | NI_65XX_CLR_OVERFLOW_INT,
dev->mmio + NI_65XX_CLR_REG);
- comedi_buf_write_samples(s, &s->state, 1);
+ comedi_buf_write_samples(s, &val, 1);
comedi_handle_events(dev, s);
return IRQ_HANDLED;
--
2.30.0
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next prev parent reply other threads:[~2021-02-23 14:32 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-23 14:30 [PATCH 00/14] staging: comedi: Fix some command data endian problems Ian Abbott
2021-02-23 14:30 ` [PATCH 01/14] staging: comedi: addi_apci_1032: Fix endian problem for COS sample Ian Abbott
2021-02-23 14:30 ` [PATCH 02/14] staging: comedi: addi_apci_1500: Fix endian problem for command sample Ian Abbott
2021-02-23 14:30 ` [PATCH 03/14] staging: comedi: adv_pci1710: Fix endian problem for AI command data Ian Abbott
2021-02-23 14:30 ` [PATCH 04/14] staging: comedi: das6402: " Ian Abbott
2021-02-23 14:30 ` [PATCH 05/14] staging: comedi: das800: " Ian Abbott
2021-02-23 14:30 ` [PATCH 06/14] staging: comedi: dmm32at: " Ian Abbott
2021-02-23 14:30 ` [PATCH 07/14] staging: comedi: me4000: " Ian Abbott
2021-02-23 14:30 ` [PATCH 08/14] staging: comedi: pcl711: " Ian Abbott
2021-02-23 14:30 ` [PATCH 09/14] staging: comedi: pcl818: " Ian Abbott
2021-02-23 14:30 ` [PATCH 10/14] staging: comedi: amplc_pc236_common: Use 16-bit 0 for interrupt data Ian Abbott
2021-02-23 14:30 ` [PATCH 11/14] staging: comedi: comedi_parport: " Ian Abbott
2021-02-23 14:30 ` [PATCH 12/14] staging: comedi: ni_6527: " Ian Abbott
2021-02-23 14:30 ` Ian Abbott [this message]
2021-02-23 14:30 ` [PATCH 14/14] staging: comedi: pcl726: " Ian Abbott
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