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

From: Chase Southwood
Date: Tue Mar 25 2014 - 01:10:17 EST


There were just a handful of more while loops in this file that need timeouts,
and this patch takes care of them, using comedi_timeout(). A couple of new
callbacks are introduced, but there was one case where the appropriate callback
function was already defined; in this case I have just used that.

Signed-off-by: Chase Southwood <chase.southwood@xxxxxxxxx>
---
drivers/staging/comedi/drivers/s626.c | 66 ++++++++++++++++++++++++++++++-----
1 file changed, 58 insertions(+), 8 deletions(-)

diff --git a/drivers/staging/comedi/drivers/s626.c b/drivers/staging/comedi/drivers/s626.c
index 95fadf3..4dc5659 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 int s626_i2c_handshake_eoc(struct comedi_device *dev,
+ struct comedi_subdevice *s,
+ struct comedi_insn *insn,
+ unsigned long context)
+{
+ unsigned int status;
+
+ status = s626_mc_test(dev, S626_MC2_UPLD_IIC, S626_P_MC2);
+ if (status)
+ return 0;
+ return -EBUSY;
+}
+
static uint32_t s626_i2c_handshake(struct comedi_device *dev, uint32_t val)
{
struct s626_private *devpriv = dev->private;
unsigned int ctrl;
+ uint32_t 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. */

@@ -2641,6 +2657,36 @@ static int s626_allocate_dma_buffers(struct comedi_device *dev)
return 0;
}

+enum {
+ s626_initialize_wait_i2c_abort,
+ s626_initialize_wait_i2c_err_reset
+};
+
+static int s626_initialize_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;
+
+ switch (context) {
+ case s626_initialize_wait_i2c_abort:
+ status = readl(devpriv->mmio + S626_P_MC2);
+ if (status & S626_MC2_UPLD_IIC)
+ return 0;
+ break;
+ case s626_initialize_wait_i2c_err_reset:
+ status = s626_mc_test(dev, S626_MC2_UPLD_IIC, S626_P_MC2);
+ if (status)
+ return 0;
+ break;
+ default:
+ return -EINVAL;
+ }
+ return -EBUSY;
+}
+
static int s626_initialize(struct comedi_device *dev)
{
struct s626_private *devpriv = dev->private;
@@ -2681,8 +2727,10 @@ 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_initialize_eoc,
+ s626_initialize_wait_i2c_abort);
+ if (ret)
+ return ret;

/*
* Per SAA7146 data sheet, write to STATUS
@@ -2691,8 +2739,10 @@ 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_initialize_eoc,
+ s626_initialize_wait_i2c_err_reset);
+ if (ret)
+ return ret;
}

/*
--
1.8.5.3

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