[PATCHv3 5/8] i2c: omap: re-factor omap_i2c_init function
Shubhrajyoti D
shubhrajyoti at ti.com
Mon Nov 5 07:23:40 EST 2012
re-factor omap_i2c_init() so that we can re-use it for resume.
While at it also remove the bufstate variable as we write it
in omap_i2c_resize_fifo for every transfer.
Reviewed-by: Felipe Balbi <balbi at ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti at ti.com>
---
drivers/i2c/busses/i2c-omap.c | 75 +++++++++++++++++++----------------------
1 files changed, 35 insertions(+), 40 deletions(-)
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 88358d8..393bb22 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -209,7 +209,6 @@ struct omap_i2c_dev {
u16 pscstate;
u16 scllstate;
u16 sclhstate;
- u16 bufstate;
u16 syscstate;
u16 westate;
u16 errata;
@@ -275,9 +274,34 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
(i2c_dev->regs[reg] << i2c_dev->reg_shift));
}
+static void __omap_i2c_init(struct omap_i2c_dev *dev)
+{
+
+ omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
+
+ /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
+ omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
+
+ /* SCL low and high time values */
+ omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
+ omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
+ if (dev->rev >= OMAP_I2C_REV_ON_3430_3530)
+ omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
+
+ /* Take the I2C module out of reset: */
+ omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
+
+ /*
+ * Don't write to this register if the IE state is 0 as it can
+ * cause deadlock.
+ */
+ if (dev->iestate)
+ omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
+}
+
static int omap_i2c_init(struct omap_i2c_dev *dev)
{
- u16 psc = 0, scll = 0, sclh = 0, buf = 0;
+ u16 psc = 0, scll = 0, sclh = 0;
u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
unsigned long fclk_rate = 12000000;
unsigned long timeout;
@@ -327,11 +351,8 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
* REVISIT: Some wkup sources might not be needed.
*/
dev->westate = OMAP_I2C_WE_ALL;
- omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
- dev->westate);
}
}
- omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
/*
@@ -416,28 +437,17 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
}
- /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
- omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
-
- /* SCL low and high time values */
- omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
- omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
-
- /* Take the I2C module out of reset: */
- omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
-
- /* Enable interrupts */
dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
OMAP_I2C_IE_AL) | ((dev->fifo_size) ?
(OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0);
- omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
- if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
- dev->pscstate = psc;
- dev->scllstate = scll;
- dev->sclhstate = sclh;
- dev->bufstate = buf;
- }
+
+ dev->pscstate = psc;
+ dev->scllstate = scll;
+ dev->sclhstate = sclh;
+
+ __omap_i2c_init(dev);
+
return 0;
}
@@ -1297,23 +1307,8 @@ static int omap_i2c_runtime_resume(struct device *dev)
if (!_dev->regs)
return 0;
- if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
- omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
- omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
- omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
- omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
- omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
- omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
- omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
- omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
- }
-
- /*
- * Don't write to this register if the IE state is 0 as it can
- * cause deadlock.
- */
- if (_dev->iestate)
- omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
+ if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE)
+ __omap_i2c_init(_dev);
return 0;
}
--
1.7.5.4
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