[PATCH v3] staging: comedi: s626: use comedi_timeout() on remaining loops

From: Chase Southwood
Date: Thu Apr 03 2014 - 19:43:51 EST


There were just a handful of more while loops in this file that needed
timeouts, and this patch takes care of them. One new callback is
introduced, and all of the proper comedi_timeout() calls are then used.
The return type of s626_i2c_handshake() has been changed from uint32_t to
int so that a negative error code from comedi_timeout() can be propagated
if necessary.

Signed-off-by: Chase Southwood <chase.southwood@xxxxxxxxx>
---
2: s626_i2c_handshake_eoc() can be used in s626_initialize() as noted by
Ian. So, s626_initialize_eoc() has been removed, and its uses swapped
for s626_i2c_handshake_eoc().

3: *Type of 'status' variable in s626_i2c_handshake_eoc() has been
corrected to bool (the return type of s626_mc_test()).
*Return type of s626_i2c_handshake() has been changed to int to allow
returning negative error codes.
*Type of 'ret' variable in the same function has been changed to int for
the same reason.
drivers/staging/comedi/drivers/s626.c | 36 ++++++++++++++++++++++++++---------
1 file changed, 27 insertions(+), 9 deletions(-)

diff --git a/drivers/staging/comedi/drivers/s626.c b/drivers/staging/comedi/drivers/s626.c
index 95fadf3..6da43de 100644
--- a/drivers/staging/comedi/drivers/s626.c
+++ b/drivers/staging/comedi/drivers/s626.c
@@ -295,10 +295,24 @@ static void s626_debi_replace(struct comedi_device *dev, unsigned int addr,

/* ************** EEPROM ACCESS FUNCTIONS ************** */

-static uint32_t s626_i2c_handshake(struct comedi_device *dev, uint32_t val)
+static int s626_i2c_handshake_eoc(struct comedi_device *dev,
+ struct comedi_subdevice *s,
+ struct comedi_insn *insn,
+ unsigned long context)
+{
+ bool status;
+
+ status = s626_mc_test(dev, S626_MC2_UPLD_IIC, S626_P_MC2);
+ if (status)
+ return 0;
+ return -EBUSY;
+}
+
+static int s626_i2c_handshake(struct comedi_device *dev, uint32_t val)
{
struct s626_private *devpriv = dev->private;
unsigned int ctrl;
+ int ret;

/* Write I2C command to I2C Transfer Control shadow register */
writel(val, devpriv->mmio + S626_P_I2CCTRL);
@@ -308,8 +322,9 @@ static uint32_t s626_i2c_handshake(struct comedi_device *dev, uint32_t val)
* wait for upload confirmation.
*/
s626_mc_enable(dev, S626_MC2_UPLD_IIC, S626_P_MC2);
- while (!s626_mc_test(dev, S626_MC2_UPLD_IIC, S626_P_MC2))
- ;
+ ret = comedi_timeout(dev, NULL, NULL, s626_i2c_handshake_eoc, 0);
+ if (ret)
+ return ret;

/* Wait until I2C bus transfer is finished or an error occurs */
do {
@@ -2029,8 +2044,9 @@ static int s626_ai_insn_read(struct comedi_device *dev,
/* Wait for the data to arrive in FB BUFFER 1 register. */

/* 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 from audio interface's input shift register. */

@@ -2681,8 +2697,9 @@ static int s626_initialize(struct comedi_device *dev)
writel(S626_I2C_CLKSEL | S626_I2C_ABORT,
devpriv->mmio + S626_P_I2CSTAT);
s626_mc_enable(dev, S626_MC2_UPLD_IIC, S626_P_MC2);
- while (!(readl(devpriv->mmio + S626_P_MC2) & S626_MC2_UPLD_IIC))
- ;
+ ret = comedi_timeout(dev, NULL, NULL, s626_i2c_handshake_eoc, 0);
+ if (ret)
+ return ret;

/*
* Per SAA7146 data sheet, write to STATUS
@@ -2691,8 +2708,9 @@ static int s626_initialize(struct comedi_device *dev)
for (i = 0; i < 2; i++) {
writel(S626_I2C_CLKSEL, devpriv->mmio + S626_P_I2CSTAT);
s626_mc_enable(dev, S626_MC2_UPLD_IIC, S626_P_MC2);
- while (!s626_mc_test(dev, S626_MC2_UPLD_IIC, S626_P_MC2))
- ;
+ ret = comedi_timeout(dev, NULL, NULL, s626_i2c_handshake_eoc, 0);
+ if (ret)
+ return ret;
}

/*
--
1.9.0

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