[PATCH v4 3/3] mfd: arizona: Refactor arizona_poll_reg

From: Charles Keepax
Date: Wed Mar 15 2017 - 10:59:17 EST


Currently, we specify the timeout in terms of the number of polls but it
is more clear from a user of the functions perspective to specify the
timeout directly in milliseconds, as such update the function to these new
semantics.

Additionally, arizona_poll_reg essentially hard-codes
regmap_read_poll_timeout, update the implementation to use
regmap_read_poll_timeout. We still keep arizona_poll_reg around as
regmap_read_poll_timeout is a macro so rather than expand this for each
caller keep it wrapped in arizona_poll_reg.

Whilst we are doing this make the timeouts a little more generous as
the previous system had a bit more slack as it was done as a delay per
iteration of the loop whereas regmap_read_poll_timeout compares ktime's.

Signed-off-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
---

Changes since v3:
- Squashed together patches 3/4 from the v3 chain.

Thanks,
Charles

drivers/mfd/arizona-core.c | 36 ++++++++++++++++--------------------
1 file changed, 16 insertions(+), 20 deletions(-)

diff --git a/drivers/mfd/arizona-core.c b/drivers/mfd/arizona-core.c
index 4cb34c3..75488e6 100644
--- a/drivers/mfd/arizona-core.c
+++ b/drivers/mfd/arizona-core.c
@@ -235,29 +235,25 @@ static irqreturn_t arizona_overclocked(int irq, void *data)
return IRQ_HANDLED;
}

+#define ARIZONA_REG_POLL_DELAY_US 7500
+
static int arizona_poll_reg(struct arizona *arizona,
- int timeout, unsigned int reg,
+ int timeout_ms, unsigned int reg,
unsigned int mask, unsigned int target)
{
unsigned int val = 0;
- int ret, i;
-
- for (i = 0; i < timeout; i++) {
- ret = regmap_read(arizona->regmap, reg, &val);
- if (ret != 0) {
- dev_err(arizona->dev, "Failed to read reg 0x%x: %d\n",
- reg, ret);
- continue;
- }
-
- if ((val & mask) == target)
- return 0;
+ int ret;

- usleep_range(1000, 5000);
- }
+ ret = regmap_read_poll_timeout(arizona->regmap,
+ ARIZONA_INTERRUPT_RAW_STATUS_5, val,
+ ((val & mask) == target),
+ ARIZONA_REG_POLL_DELAY_US,
+ timeout_ms * 1000);
+ if (ret)
+ dev_err(arizona->dev, "Polling reg 0x%x timed out: %x\n",
+ reg, val);

- dev_err(arizona->dev, "Polling reg 0x%x timed out: %x\n", reg, val);
- return -ETIMEDOUT;
+ return ret;
}

static int arizona_wait_for_boot(struct arizona *arizona)
@@ -269,7 +265,7 @@ static int arizona_wait_for_boot(struct arizona *arizona)
* we won't race with the interrupt handler as it'll be blocked on
* runtime resume.
*/
- ret = arizona_poll_reg(arizona, 5, ARIZONA_INTERRUPT_RAW_STATUS_5,
+ ret = arizona_poll_reg(arizona, 30, ARIZONA_INTERRUPT_RAW_STATUS_5,
ARIZONA_BOOT_DONE_STS, ARIZONA_BOOT_DONE_STS);

if (!ret)
@@ -339,7 +335,7 @@ static int arizona_enable_freerun_sysclk(struct arizona *arizona,
ret);
return ret;
}
- ret = arizona_poll_reg(arizona, 25, ARIZONA_INTERRUPT_RAW_STATUS_5,
+ ret = arizona_poll_reg(arizona, 180, ARIZONA_INTERRUPT_RAW_STATUS_5,
ARIZONA_FLL1_CLOCK_OK_STS,
ARIZONA_FLL1_CLOCK_OK_STS);
if (ret)
@@ -403,7 +399,7 @@ static int wm5102_apply_hardware_patch(struct arizona *arizona)
goto err;
}

- ret = arizona_poll_reg(arizona, 5, ARIZONA_WRITE_SEQUENCER_CTRL_1,
+ ret = arizona_poll_reg(arizona, 30, ARIZONA_WRITE_SEQUENCER_CTRL_1,
ARIZONA_WSEQ_BUSY, 0);
if (ret)
regmap_write(arizona->regmap, ARIZONA_WRITE_SEQUENCER_CTRL_0,
--
2.1.4